[RFC PATCH 0/5] omv6211 linux kernel driver

[RFC PATCH 0/5] omv6211 linux kernel driver

[Petko Manolov]

This series adds ovm6211 driver into the staging directory.  It also creates
media/i2c entry, where ovm6211.c lives for now, to mimic the generic media
source tree.

It is also marked as RFC because i expect some insonsistencies with V4L2.

Petko Manolov (5):
  adds ovm6211 driver to staging
  adds ovm6211 entry to Kconfig
  adds ovm6211 entry to Makefile
  adds drivers/staging/media/i2c/Kconfig entry
  adds i2c/ explicitly to Makefile

 drivers/staging/media/Kconfig       |    2 +
 drivers/staging/media/Makefile      |    1 +
 drivers/staging/media/i2c/Kconfig   |    9 +
 drivers/staging/media/i2c/Makefile  |    1 +
 drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++
 5 files changed, 1169 insertions(+)
 create mode 100644 drivers/staging/media/i2c/Kconfig
 create mode 100644 drivers/staging/media/i2c/Makefile
 create mode 100644 drivers/staging/media/i2c/ovm6211.c

-- 
2.30.2

[RFC PATCH 1/5] adds ovm6211 driver to staging

[Petko Manolov]

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
---
 drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++
 1 file changed, 1156 insertions(+)
 create mode 100644 drivers/staging/media/i2c/ovm6211.c

diff --git a/drivers/staging/media/i2c/ovm6211.c b/drivers/staging/media/i2c/ovm6211.c
new file mode 100644
index 000000000000..a89c5167a892
--- /dev/null
+++ b/drivers/staging/media/i2c/ovm6211.c
@@ -0,0 +1,1156 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Based on ov5640.c that lives in the same directory.
+ *
+ * Copyright (C) 2021 Petko Manolov <petko.manolov@konsulko.com>
+ * Copyright (C) 2021 DEKA Research & Development Corp.
+ */
+
+#define	DEBUG
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/of_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-subdev.h>
+
+/* Min/max system clock (xvclk) frequencies */
+#define OVM6211_XVCLK_MIN	 6000000
+#define OVM6211_XVCLK_MAX	27000000
+
+/* begin of OVM6211 definitions */
+/* System Control */
+#define OVM6211_SC_MODE_SELECT		0x0100
+#define OVM6211_SC_SOFTWARE_RESET	0x0103
+#define OVM6211_SC_SCCB_ID1		0x0109
+#define OVM6211_SC_CHIP_ID_HIGH		0x300a
+#define OVM6211_SC_CHIP_ID_LOW		0x300b
+#define OVM6211_SC_REG0C		0x300c
+#define OVM6211_SC_REG10		0x3010
+#define OVM6211_SC_MIPI_PHY		0x3012
+#define OVM6211_SC_MIPI_PHY2		0x3013
+#define OVM6211_SC_MIPI_SC_CTRL0	0x3014
+#define OVM6211_SC_MIPI_SC_CTRL1	0x3015
+#define OVM6211_SC_CLKRST0		0x3016
+#define OVM6211_SC_CLKRST1		0x3017
+#define OVM6211_SC_CLKRST2		0x3018
+#define OVM6211_SC_CLKRST3		0x3019
+#define OVM6211_SC_CLKRST4		0x301a
+#define OVM6211_SC_CLKRST5		0x301b
+#define OVM6211_SC_CLKRST6		0x301c
+#define OVM6211_SC_CLOCK_SEL		0x301e
+#define OVM6211_SC_MISC_CTRL		0x301f
+#define OVM6211_SC_LOW_PWR_CTRL		0x3023
+#define OVM6211_SC_REG27		0x3027
+#define OVM6211_SC_GP_IO_IN1		0x3029
+#define OVM6211_SC_GP_IO_IN2		0x302a
+#define OVM6211_SC_SCCB_ID2		0x302b
+#define OVM6211_SC_AUTO_SLEEP_PERIOD0	0x302c
+#define OVM6211_SC_AUTO_SLEEP_PERIOD1	0x302d
+#define OVM6211_SC_AUTO_SLEEP_PERIOD2	0x302e
+#define OVM6211_SC_AUTO_SLEEP_PERIOD3	0x302f
+#define OVM6211_SC_LP_CTRL0		0x3030
+#define OVM6211_SC_REG37		0x3037
+#define OVM6211_SC_REG3B		0x303b
+/* PLL Control */
+#define OVM6211_PLL_PLL0		0x3080
+#define OVM6211_PLL_PLL1		0x3081
+#define OVM6211_PLL_PLL2		0x3082
+#define OVM6211_PLL_PLL18		0x3098
+#define OVM6211_PLL_PLL19		0x3099
+#define OVM6211_PLL_PLL1A		0x309a
+#define OVM6211_PLL_PLL1B		0x309b
+#define OVM6211_PLL_PLL1C		0x309c
+#define OVM6211_PLL_PLL1D		0x309d
+#define OVM6211_PLL_PLL1E		0x309e
+#define OVM6211_PLL_PLL1F		0x309f
+#define OVM6211_PLL_VT_PIX_CLK_DIV	0x30b0
+#define OVM6211_PLL_VT_SYS_CLK_DIV	0x30b1
+#define OVM6211_PLL_MULTIPLIER		0x30b3
+#define OVM6211_PLL_PLL1_PRE_PLL_DIV	0x30b4
+#define OVM6211_PLL_PLL1_OP_PIX_CLK_DIV	0x30b5
+#define OVM6211_PLL_PLL1_OP_SYS_CLK_DIV	0x30b6
+/* SCCB and group hold */
+#define OVM6211_SB_SRB_CTRL		0x3106
+#define OVM6211_SB_SWITCH		0x31ff
+/* AEC/AGC */
+#define OVM6211_AEC_EXPO1		0x3500
+#define OVM6211_AEC_EXPO2		0x3501
+#define OVM6211_AEC_EXPO3		0x3502
+#define OVM6211_AEC_MANUAL		0x3503
+#define OVM6211_AGC_MAN_SNR_GAIN1	0x3504
+#define OVM6211_AGC_MAN_SNR_GAIN2	0x3505
+/* timing conrol registers */
+#define	OVM6211_TVTS_HI			0x380e
+#define	OVM6211_TVTS_LO			0x380f
+/*Strobe frame span registers*/
+#define OVM6211_STROBE_SPAN1		0x3b8d
+#define OVM6211_STROBE_SPAN2		0x3b8e
+#define OVM6211_STROBE_SPAN3		0x3b8f
+/* format control */
+#define OVM6211_DATA_MAX_H		0x4300
+#define OVM6211_DATA_MIN_H		0x4301
+#define OVM6211_CLIP_L			0x4302
+#define OVM6211_FORMAT_CTRL3		0x4303
+#define OVM6211_FORMAT_CTRL4		0x4304
+#define OVM6211_VSYNC_WIDTH_H		0x4311
+#define OVM6211_VSYNC_WIDTH_L		0x4312
+#define OVM6211_VSYNC_CTRL		0x4313
+#define OVM6211_VSYNC_DELAY1		0x4314
+#define OVM6211_VSYNC_DELAY2		0x4315
+#define OVM6211_VSYNC_DELAY3		0x4316
+#define OVM6211_TST_PATTERN_CTRL	0x4320
+/* MIPI */
+#define OVM6211_MIPI_CTRL00		0x4800
+#define OVM6211_MIPI_CTRL01		0x4801
+#define OVM6211_MIPI_CTRL02		0x4802
+#define OVM6211_MIPI_CTRL03		0x4803
+#define OVM6211_MIPI_CTRL04		0x4804
+#define OVM6211_MIPI_CTRL05		0x4805
+#define OVM6211_MIPI_CTRL06		0x4806
+#define OVM6211_MIPI_MAX_FRAME_COUNT_H	0x4810
+#define OVM6211_MIPI_MAX_FRAME_COUNT_L	0x4811
+#define OVM6211_MIPI_SHORT_PKT_COUNTER_H	0x4812
+#define OVM6211_MIPI_SHORT_PKT_COUNTER_L	0x4813
+#define OVM6211_MIPI_CTRL14		0x4814
+#define OVM6211_MIPI_DT_SPKT		0x4815
+#define OVM6211_MIPI_REG_MAX_H		0x4835
+#define OVM6211_MIPI_REG_MAX_L		0x4836
+#define OVM6211_PCLK_PERIOD		0x4837
+#define OVM6211_WKUP_DLY		0x4838
+#define OVM6211_DIR_DLY			0x483a
+#define OVM6211_MIPI_LP_GPIO		0x483b
+#define OVM6211_MIPI_CTRL3C		0x483c
+#define OVM6211_T_TA_GO			0x483d
+#define OVM6211_T_TA_SURE		0x483e
+#define OVM6211_T_TA_GET		0x483f
+#define OVM6211_MIPI_CLIP_MAX_H		0x4846
+#define OVM6211_MIPI_CLIP_MAX_L		0x4847
+#define OVM6211_MIPI_CLIP_MIN_H		0x4848
+#define OVM6211_MIPI_CLIP_MIN_L		0x4848
+#define OVM6211_REG_INTR_MAN		0x4850
+#define OVM6211_REG_TX_WR		0x4851
+/* ISP top */
+#define OVM6211_ISP_CTRL00		0x5000
+#define OVM6211_ISP_CTRL01		0x5001
+#define OVM6211_ISP_CTRL02		0x5002
+#define OVM6211_ISP_CTRL03		0x5003
+#define OVM6211_ISP_CTRL04		0x5004
+#define OVM6211_ISP_CTRL05		0x5005
+#define OVM6211_ISP_CTRL06		0x5006
+#define OVM6211_ISP_CTRL07		0x5007
+#define OVM6211_ISP_CTRL08		0x5008
+#define OVM6211_ISP_CTRL09		0x5009
+/* window control */
+#define OVM6211_MAN_XSTART_OFF_H	0x5a00
+#define OVM6211_MAN_XSTART_OFF_L	0x5a01
+#define OVM6211_MAN_YSTART_OFF_H	0x5a02
+#define OVM6211_MAN_YSTART_OFF_L	0x5a03
+#define OVM6211_MAN_WIN_WIDTH_H		0x5a04
+#define OVM6211_MAN_WIN_WIDTH_L		0x5a05
+#define OVM6211_MAN_WIN_HEIGHT_H	0x5a06
+#define OVM6211_MAN_WIN_HEIGHT_L	0x5a07
+#define OVM6211_WIN_MAN			0x5a08
+
+#define	OVM6211_LAST_REG		0x5e08
+/* end of OVM6211 definitions */
+
+enum ovm6211_mode_id {
+	OVM6211_MODE_Y8_400_200 = 0,
+	OVM6211_MODE_Y8_400_400,
+	OVM6211_NUM_MODES,
+};
+
+struct ovm6211_pixfmt {
+	u32 code;
+	u32 colorspace;
+};
+
+static const struct ovm6211_pixfmt ovm6211_formats[] = {
+	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
+	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
+};
+
+enum ovm6211_framerate_ids {
+	OVM6211_10_FPS = 0,
+	OVM6211_15_FPS,
+	OVM6211_30_FPS,
+	OVM6211_45_FPS,
+	OVM6211_60_FPS,
+	OVM6211_NUM_FRAMERATES,
+};
+
+static const int ovm6211_framerates[] = {
+	[OVM6211_10_FPS] = 10,
+	[OVM6211_15_FPS] = 15,
+	[OVM6211_30_FPS] = 30,
+	[OVM6211_45_FPS] = 45,
+	[OVM6211_60_FPS] = 60,
+};
+
+/* regulator supplies */
+static const char * const ovm6211_supply_name[] = {
+	"dovdd",
+	"avdd",
+};
+
+#define OVM6211_NUM_SUPPLIES ARRAY_SIZE(ovm6211_supply_name)
+
+static const struct regmap_config ovm6211_regmap_config = {
+	.reg_bits       = 16,
+	.val_bits       = 8,
+	.max_register   = OVM6211_LAST_REG,
+	.cache_type	= REGCACHE_NONE,
+};
+
+struct reg_value {
+	u16 reg_addr;
+	u8 val;
+	u8 mask;
+	u32 delay_ms;
+};
+
+struct ovm6211_mode_info {
+	enum ovm6211_mode_id id;
+	u32 width;
+	u32 height;
+	const struct reg_value *reg_data;
+	u32 reg_data_size;
+	u32 pixel_clock;
+};
+
+struct ovm6211_ctrls {
+	struct v4l2_ctrl_handler handler;
+	struct {
+		struct v4l2_ctrl *auto_exp;
+		struct v4l2_ctrl *exposure;
+	};
+	struct {
+		struct v4l2_ctrl *auto_gain;
+		struct v4l2_ctrl *gain;
+	};
+	struct v4l2_ctrl *brightness;
+	struct v4l2_ctrl *light_freq;
+	struct v4l2_ctrl *saturation;
+	struct v4l2_ctrl *contrast;
+	struct v4l2_ctrl *hue;
+	struct v4l2_ctrl *test_pattern;
+	struct v4l2_ctrl *link_freq;
+	struct v4l2_ctrl *pixel_clock;
+};
+
+struct ovm6211_dev {
+	struct i2c_client *i2c_client;
+	struct regmap *regmap;
+	struct v4l2_subdev sd;
+	struct media_pad pad;
+	struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
+	struct clk *xclk; /* system clock to OVM6211 */
+	u32 xclk_freq;
+
+	struct regulator_bulk_data supplies[OVM6211_NUM_SUPPLIES];
+	struct gpio_desc *reset_gpio;
+	struct gpio_desc *pwdn_gpio;
+
+	struct mutex lock;
+
+	struct v4l2_mbus_framefmt fmt;
+
+	const struct ovm6211_mode_info *cur_mode;
+	enum ovm6211_framerate_ids cur_fr_id;
+	struct v4l2_fract frame_interval;
+
+	struct ovm6211_ctrls ctrls;
+
+	u32 exposure;
+	bool pending_mode_change;
+	bool pending_fi_change;
+	bool streaming;
+};
+
+static inline struct ovm6211_dev *to_ovm6211_dev(struct v4l2_subdev *sd)
+{
+	return container_of(sd, struct ovm6211_dev, sd);
+}
+
+static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
+{
+	return &container_of(ctrl->handler, struct ovm6211_dev,
+			     ctrls.handler)->sd;
+}
+
+static const struct reg_value ovm6211_init_y8_400_400[] = {
+	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
+	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
+	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
+	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
+	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
+	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
+	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
+	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
+	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
+	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
+	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
+	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
+	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
+	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
+	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
+	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
+	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
+	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
+	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
+	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
+	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
+	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
+	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
+	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0}, {0x3808, 0x01, 0, 0},
+	{0x3809, 0x90, 0, 0}, {0x380a, 0x01, 0, 0}, {0x380b, 0x90, 0, 0},
+	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x03, 0, 0},
+	{0x380f, 0x6c, 0, 0}, {0x3810, 0x00, 0, 0}, {0x3811, 0x04, 0, 0},
+	{0x3812, 0x00, 0, 0}, {0x3813, 0x04, 0, 0}, {0x3814, 0x11, 0, 0},
+	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
+	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
+	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
+	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
+	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
+	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
+	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
+	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
+	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
+	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
+	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
+	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
+	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
+	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
+	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
+};
+
+static const struct reg_value ovm6211_init_y8_400_200[] = {
+	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
+	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
+	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
+	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
+	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
+	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
+	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
+	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
+	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
+	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
+	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
+	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
+	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
+	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
+	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
+	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
+	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
+	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
+	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
+	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
+	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
+	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
+	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
+	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0},
+	{0x3808, 0x01, 0, 0},	// W
+	{0x3809, 0x90, 0, 0},	// W
+	{0x380a, 0x00, 0, 0},	// H
+	{0x380b, 0xc8, 0, 0},	// H
+	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x0d, 0, 0},
+	{0x380f, 0xb0, 0, 0},
+	{0x3810, 0x00, 0, 0},	// W off
+	{0x3811, 0x04, 0, 0},	// W off: 4 + (400 - x_width)/2
+	{0x3812, 0x00, 0, 0},	// H off
+	{0x3813, 0x9a, 0, 0},	// H off: 4 + (400 - y_height)/2
+	{0x3814, 0x11, 0, 0},
+	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
+	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
+	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
+	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
+	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
+	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
+	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
+	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
+	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
+	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
+	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
+	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
+	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
+	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
+	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
+};
+
+/* power-on sensor init reg table */
+static const struct ovm6211_mode_info *ovm6211_mode_init_data;
+
+static struct ovm6211_mode_info
+ovm6211_mode_data[OVM6211_NUM_MODES] = {
+	{OVM6211_MODE_Y8_400_200,
+	 400, 200,
+	 ovm6211_init_y8_400_200,
+	 ARRAY_SIZE(ovm6211_init_y8_400_200),
+	 400 * 400 * 60 * 2,
+	},
+	{OVM6211_MODE_Y8_400_400,
+	 400, 400,
+	 ovm6211_init_y8_400_400,
+	 ARRAY_SIZE(ovm6211_init_y8_400_400),
+	 400 * 400 * 60 * 2,
+	},
+};
+
+static const s64 link_freq_menu_items[] = {
+	0,
+};
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int ovm6211_get_register(struct v4l2_subdev *sd,
+				struct v4l2_dbg_register *reg)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	struct regmap *regmap = sensor->regmap;
+	unsigned int val = 0;
+	int ret;
+
+	ret = regmap_read(regmap, reg->reg, &val);
+	reg->val = val;
+	reg->size = 1;
+
+	return ret;
+}
+
+static int ovm6211_set_register(struct v4l2_subdev *sd,
+				const struct v4l2_dbg_register *reg)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	struct regmap *regmap = sensor->regmap;
+
+	return regmap_write(regmap, reg->reg, reg->val & 0xff);
+}
+#endif
+
+static int ovm6211_write_reg(struct ovm6211_dev *sensor, u16 reg, u8 val)
+{
+	struct i2c_client *client = sensor->i2c_client;
+	struct regmap *regmap = sensor->regmap;
+	int ret;
+
+	ret = regmap_write(regmap, reg, val);
+	if (ret < 0)
+		dev_err(&client->dev, "error writing reg %u\n", reg);
+
+	return ret;
+}
+
+static int ovm6211_read_reg(struct ovm6211_dev *sensor, u16 reg, u8 *val)
+{
+	struct i2c_client *client = sensor->i2c_client;
+	struct regmap *regmap = sensor->regmap;
+	unsigned int r;
+	int ret;
+
+	ret = regmap_read(regmap, reg, &r);
+	if (ret < 0)
+		dev_err(&client->dev, "error reading reg %u\n", reg);
+	*val = r & 0xff;
+
+	return ret;
+}
+
+static int ovm6211_mod_reg(struct ovm6211_dev *sensor, u16 reg, u8 mask, u8 val)
+{
+	u8 readval;
+	int ret;
+
+	ret = ovm6211_read_reg(sensor, reg, &readval);
+	if (ret)
+		return ret;
+
+	readval &= ~mask;
+	val &= mask;
+	val |= readval;
+
+	return ovm6211_write_reg(sensor, reg, val);
+}
+
+static int ovm6211_load_regs(struct ovm6211_dev *sensor,
+			     const struct ovm6211_mode_info *mode)
+{
+	const struct reg_value *regs = mode->reg_data;
+	unsigned int i;
+	u32 delay_ms;
+	u16 reg_addr;
+	u8 mask, val;
+	int ret = 0;
+
+	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
+		delay_ms = regs->delay_ms;
+		reg_addr = regs->reg_addr;
+		val = regs->val;
+		mask = regs->mask;
+		if (mask)
+			ret = ovm6211_mod_reg(sensor, reg_addr, mask, val);
+		else
+			ret = ovm6211_write_reg(sensor, reg_addr, val);
+		if (ret)
+			break;
+
+		if (delay_ms) {
+			usleep_range(1000 * delay_ms, 1000 * delay_ms + 100);
+		}
+	}
+
+	return ret;
+}
+
+static void ovm6211_soft_reset(struct ovm6211_dev *sensor)
+{
+	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x01);
+	usleep_range(5000, 9000);
+	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x00);
+}
+
+static int ovm6211_set_exposure(struct ovm6211_dev *sensor, u32 exposure)
+{
+	u32 ce;
+	u8 v;
+
+	ovm6211_read_reg(sensor, OVM6211_TVTS_HI, &v);
+	ce = v << 8;
+	ovm6211_read_reg(sensor, OVM6211_TVTS_LO, &v);
+	ce |= v;
+	ce -= 4;
+
+	if (ce < exposure)
+		exposure = ce;
+
+	ovm6211_mod_reg(sensor, OVM6211_AEC_MANUAL, 1, 1);
+	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO1, (exposure >> 12) & 0x0f);
+	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO2, (exposure >>  4) & 0xff);
+	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO3, (exposure <<  4) & 0xf0);
+
+	/* set strobe width equal to exposure time */
+	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN1, (exposure >> 16) & 0xff);
+	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN2, (exposure >>  8) & 0xff);
+	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN3, (exposure)       & 0xff);
+
+	return 0;
+}
+
+static int internal_set_stream(struct ovm6211_dev *sensor, bool on)
+{
+	u8 hi, lo;
+
+	if (sensor->pending_fi_change == false)
+		goto stream;
+
+	switch (sensor->cur_fr_id) {
+	case OVM6211_10_FPS:
+		hi = 0x14;
+		lo = 0x88;
+		break;
+	case OVM6211_15_FPS:
+		hi = 0x0d;
+		lo = 0xb0;
+		break;
+	case OVM6211_30_FPS:
+		hi = 0x06;
+		lo = 0xd8;
+		break;
+	case OVM6211_45_FPS:
+		hi=0x04;
+		lo = 0x90;
+		break;
+	case OVM6211_60_FPS:
+		hi=0x03;
+		lo = 0x6c;
+		break;
+	case OVM6211_NUM_FRAMERATES:
+		return -EINVAL;
+	}
+
+	sensor->pending_fi_change = false;
+	ovm6211_write_reg(sensor, OVM6211_TVTS_HI, hi);
+	ovm6211_write_reg(sensor, OVM6211_TVTS_LO, lo);
+stream:
+	ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 0);
+	if (on) {
+		usleep_range(4000, 5000);
+		if (sensor->exposure)
+			ovm6211_set_exposure(sensor, sensor->exposure);
+		ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 1);
+		sensor->streaming = true;
+	} else {
+		sensor->streaming = false;
+	}
+
+	return 0;
+}
+
+static struct ovm6211_mode_info *ovm6211_find_mode(int w, int h)
+{
+	return v4l2_find_nearest_size(ovm6211_mode_data,
+				      ARRAY_SIZE(ovm6211_mode_data),
+				      width, height, w, h);
+}
+
+static int ovm6211_set_mode(struct ovm6211_dev *sensor)
+{
+	const struct ovm6211_mode_info *mode = sensor->cur_mode;
+
+	ovm6211_soft_reset(sensor);
+	ovm6211_load_regs(sensor, mode);
+
+	return 0;
+}
+
+/* --------------- Subdev Operations --------------- */
+
+static int ovm6211_get_fmt(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_state *state,
+			   struct v4l2_subdev_format *format)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	struct v4l2_mbus_framefmt *fmt;
+
+	if (format->pad != 0)
+		return -EINVAL;
+
+	mutex_lock(&sensor->lock);
+
+	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
+		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
+		format->format = *fmt;
+	} else {
+		/* these are hardcoded as we don't support anything else */
+		format->format.colorspace  = V4L2_COLORSPACE_RAW;
+		format->format.field = V4L2_FIELD_NONE;
+		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
+		format->format.width = sensor->cur_mode->width;
+		format->format.height = sensor->cur_mode->height;
+	}
+
+	mutex_unlock(&sensor->lock);
+
+	return 0;
+}
+
+u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
+{
+	u32 s, fmt, fps, ret;
+
+	/* x * y * [1|2] * y8/y10 * fps */
+	s = nm->width * nm->height;
+	fmt = 1;
+	fps = ovm6211_framerates[sensor->cur_fr_id];
+	ret = s * fmt * fps * 2;
+
+	return ret;
+}
+
+static int ovm6211_set_fmt(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_state *state,
+			   struct v4l2_subdev_format *format)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	struct v4l2_mbus_framefmt *fmt = &format->format;
+	struct ovm6211_mode_info *mode;
+
+	if (format->pad != 0)
+		return -EINVAL;
+
+	if (sensor->streaming)
+		return -EBUSY;
+
+	mutex_lock(&sensor->lock);
+
+	/* these are hardcoded as we don't support anything else */
+	format->format.colorspace  = V4L2_COLORSPACE_RAW;
+	format->format.field = V4L2_FIELD_NONE;
+	format->format.code = MEDIA_BUS_FMT_Y8_1X8;
+	mode = ovm6211_find_mode(format->format.width, format->format.height);
+	format->format.width = mode->width;
+	format->format.height = mode->height;
+
+	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
+		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
+		*fmt = format->format;
+		goto out;
+	}
+	/* V4L2_SUBDEV_FORMAT_TRY_ACTIVE */
+	sensor->cur_mode = mode;
+out:
+	mutex_unlock(&sensor->lock);
+
+	return 0;
+}
+
+/*
+ * Sensor Controls.
+ */
+
+static int ovm6211_set_ctrl_exposure(struct ovm6211_dev *sensor, enum
+				     v4l2_exposure_auto_type auto_exposure)
+{
+	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
+
+	if (auto_exposure == V4L2_EXPOSURE_AUTO) {
+		sensor->exposure = 0;
+	} else {
+		sensor->exposure = ctrls->exposure->val;
+		ovm6211_set_exposure(sensor, sensor->exposure);
+	}
+
+	return 0;
+}
+
+static int ovm6211_set_ctrl_gain(struct ovm6211_dev *sensor, bool auto_gain)
+{
+	return 0;
+}
+
+static int ovm6211_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	int ret;
+
+	/* v4l2_ctrl_lock() locks our own mutex */
+
+	/*
+	 * If the device is not powered up by the host driver do
+	 * not apply any controls to H/W at this time. Instead
+	 * the controls will be restored right after power-up.
+	 */
+	switch (ctrl->id) {
+	case V4L2_CID_GAIN:
+		ret = ovm6211_set_ctrl_gain(sensor, ctrl->val);
+		break;
+	case V4L2_CID_EXPOSURE_AUTO:
+		ret = ovm6211_set_ctrl_exposure(sensor, ctrl->val);
+		break;
+#if 0
+	case V4L2_CID_AUTO_WHITE_BALANCE:
+		ret = ovm6211_set_ctrl_white_balance(sensor, ctrl->val);
+		break;
+	case V4L2_CID_HUE:
+		ret = ovm6211_set_ctrl_hue(sensor, ctrl->val);
+		break;
+	case V4L2_CID_CONTRAST:
+		ret = ovm6211_set_ctrl_contrast(sensor, ctrl->val);
+		break;
+	case V4L2_CID_SATURATION:
+		ret = ovm6211_set_ctrl_saturation(sensor, ctrl->val);
+		break;
+	case V4L2_CID_TEST_PATTERN:
+		ret = ovm6211_set_ctrl_test_pattern(sensor, ctrl->val);
+		break;
+	case V4L2_CID_POWER_LINE_FREQUENCY:
+		ret = ovm6211_set_ctrl_light_freq(sensor, ctrl->val);
+		break;
+#endif
+	case V4L2_CID_LINK_FREQ:
+		return 0;
+	case V4L2_CID_PIXEL_RATE:
+		return 0;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops ovm6211_ctrl_ops = {
+	.s_ctrl = ovm6211_s_ctrl,
+};
+
+static int ovm6211_init_controls(struct ovm6211_dev *sensor)
+{
+	const struct v4l2_ctrl_ops *ops = &ovm6211_ctrl_ops;
+	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
+	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
+	int ret;
+
+	v4l2_ctrl_handler_init(hdl, 32);
+
+	/* we can use our own mutex for the ctrl lock */
+	hdl->lock = &sensor->lock;
+
+	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_EXPOSURE_AUTO,
+						 V4L2_EXPOSURE_MANUAL, 0,
+						 V4L2_EXPOSURE_AUTO);
+	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
+					    0, 65535, 1, 0);
+	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN,
+					0, 1023, 1, 0);
+
+	v4l2_ctrl_auto_cluster(3, &ctrls->auto_exp, 0, false);
+
+	ctrls->saturation = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION,
+					      0, 255, 1, 64);
+	ctrls->hue = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HUE,
+				       0, 359, 1, 0);
+	ctrls->contrast = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST,
+					    0, 255, 1, 0);
+	ctrls->light_freq =
+		v4l2_ctrl_new_std_menu(hdl, ops,
+				       V4L2_CID_POWER_LINE_FREQUENCY,
+				       V4L2_CID_POWER_LINE_FREQUENCY_AUTO, 0,
+				       V4L2_CID_POWER_LINE_FREQUENCY_50HZ);
+	ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
+						  0, 0, link_freq_menu_items);
+	ctrls->pixel_clock = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
+						    1, INT_MAX, 1, 38400000);
+
+	if (hdl->error) {
+		ret = hdl->error;
+		goto free_ctrls;
+	}
+
+	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
+	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
+
+	sensor->sd.ctrl_handler = hdl;
+	return 0;
+
+free_ctrls:
+	v4l2_ctrl_handler_free(hdl);
+	return ret;
+}
+
+static int ovm6211_g_frame_interval(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_frame_interval *fi)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+
+	mutex_lock(&sensor->lock);
+	fi->interval = sensor->frame_interval;
+	mutex_unlock(&sensor->lock);
+
+	return 0;
+}
+
+static int internal_set_frame_interval(struct ovm6211_dev *sensor, struct
+				       v4l2_subdev_frame_interval *fi)
+{
+	u32 fr_rate;
+	int i, max, ret = -EINVAL;
+
+	if (fi->interval.numerator == 0)
+		goto out;
+
+	fr_rate = fi->interval.denominator / fi->interval.numerator;
+
+	max = ARRAY_SIZE(ovm6211_framerates);
+	for (i = 0; i < max; i++) {
+		if (ovm6211_framerates[i] == fr_rate)
+			break;
+	}
+
+	if (i == max)
+		goto out;
+
+	sensor->cur_fr_id = i;
+	sensor->frame_interval = fi->interval;
+	ret = 0;
+out:
+	return ret;
+}
+
+static int ovm6211_s_frame_interval(struct v4l2_subdev *sd,
+				    struct v4l2_subdev_frame_interval *fi)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	int ret;
+
+	mutex_lock(&sensor->lock);
+	ret = internal_set_frame_interval(sensor, fi);
+	sensor->pending_fi_change = true;
+	mutex_unlock(&sensor->lock);
+
+	return ret;
+}
+
+static int ovm6211_enum_mbus_code(struct v4l2_subdev *sd,
+				  struct v4l2_subdev_state *state,
+				  struct v4l2_subdev_mbus_code_enum *code)
+{
+	if (code->pad != 0)
+		return -EINVAL;
+	if (code->index >= ARRAY_SIZE(ovm6211_formats))
+		return -EINVAL;
+
+	code->code = ovm6211_formats[code->index].code;
+
+	return 0;
+}
+
+static int ovm6211_s_stream(struct v4l2_subdev *sd, int enable)
+{
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+	int ret = 0;
+
+	mutex_lock(&sensor->lock);
+
+	if (enable)
+		ret = ovm6211_set_mode(sensor);
+	internal_set_stream(sensor, enable);
+
+	mutex_unlock(&sensor->lock);
+
+	return ret;
+}
+
+static int ovm6211_set_power(struct v4l2_subdev *sd, int on)
+{
+	return 0;
+}
+
+static const struct v4l2_subdev_core_ops ovm6211_core_ops = {
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+	.g_register = ovm6211_get_register,
+	.s_register = ovm6211_set_register,
+#endif
+	.s_power = ovm6211_set_power,
+};
+
+static const struct v4l2_subdev_video_ops ovm6211_video_ops = {
+	.g_frame_interval = ovm6211_g_frame_interval,
+	.s_frame_interval = ovm6211_s_frame_interval,
+	.s_stream = ovm6211_s_stream,
+};
+
+static const struct v4l2_subdev_pad_ops ovm6211_pad_ops = {
+	.enum_mbus_code = ovm6211_enum_mbus_code,
+	.get_fmt = ovm6211_get_fmt,
+	.set_fmt = ovm6211_set_fmt,
+};
+
+static const struct v4l2_subdev_ops ovm6211_subdev_ops = {
+	.core = &ovm6211_core_ops,
+	.video = &ovm6211_video_ops,
+	.pad = &ovm6211_pad_ops,
+};
+
+static int ovm6211_get_regulators(struct ovm6211_dev *sensor)
+{
+	int i;
+
+	for (i = 0; i < OVM6211_NUM_SUPPLIES; i++)
+		sensor->supplies[i].supply = ovm6211_supply_name[i];
+
+	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
+				       OVM6211_NUM_SUPPLIES,
+				       sensor->supplies);
+}
+
+static int ovm6211_check_chip_id(struct ovm6211_dev *sensor)
+{
+	struct i2c_client *client = sensor->i2c_client;
+	struct regmap *regmap = sensor->regmap;
+	unsigned int cid;
+	int ret = 0;
+
+	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_HIGH, &cid);
+	if (ret || cid != 0x67) {
+		ret = ENXIO;
+		goto err;
+	}
+
+	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_LOW, &cid);
+	if (ret || cid != 0x10) {
+		ret = -ENXIO;
+		goto err;
+	}
+
+	ret = regmap_read(regmap, OVM6211_SC_REG0C, &cid);
+	if (ret)
+		goto err;
+
+	dev_info(&client->dev,"found OVM6211, sub revision: 0x%02X\n", cid);
+	return 0;
+err:
+	dev_err(&client->dev, "failed to detect OVM6211\n");
+	return ret;
+}
+
+static int ovm6211_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct fwnode_handle *endpoint;
+	struct ovm6211_dev *sensor;
+	struct v4l2_mbus_framefmt *fmt;
+	int ret;
+
+	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
+	if (!sensor)
+		return -ENOMEM;
+
+	sensor->i2c_client = client;
+
+	/*
+	 * default init sequence initialize sensor to
+	 * YUV422 UYVY VGA@30fps
+	 */
+	fmt = &sensor->fmt;
+	fmt->code = MEDIA_BUS_FMT_Y8_1X8;
+	fmt->colorspace = V4L2_COLORSPACE_RAW;
+	fmt->field = V4L2_FIELD_NONE;
+	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
+	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
+	fmt->width = 400;
+	fmt->height = 200;
+
+	sensor->frame_interval.numerator = 1;
+	sensor->frame_interval.denominator = ovm6211_framerates[OVM6211_45_FPS];
+	sensor->cur_fr_id = OVM6211_45_FPS;
+	ovm6211_mode_init_data = &ovm6211_mode_data[OVM6211_MODE_Y8_400_200];
+	sensor->cur_mode = ovm6211_mode_init_data;
+
+	sensor->ep.bus_type = V4L2_MBUS_CSI2_DPHY;
+	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
+	if (!endpoint) {
+		dev_err(dev, "endpoint node not found\n");
+		return -EINVAL;
+	}
+
+	ret = v4l2_fwnode_endpoint_parse(endpoint, &sensor->ep);
+	fwnode_handle_put(endpoint);
+	if (ret) {
+		dev_err(dev, "Could not parse endpoint\n");
+		return ret;
+	}
+
+	/* get system clock (xclk) */
+	sensor->xclk = devm_clk_get(dev, "xvclk");
+	if (IS_ERR(sensor->xclk)) {
+		dev_err(dev, "failed to get xvclk\n");
+		return PTR_ERR(sensor->xclk);
+	}
+
+	sensor->xclk_freq = clk_get_rate(sensor->xclk);
+	if (sensor->xclk_freq < OVM6211_XVCLK_MIN ||
+	    sensor->xclk_freq > OVM6211_XVCLK_MAX) {
+		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
+			sensor->xclk_freq);
+		return -EINVAL;
+	}
+
+	/* request optional power down pin */
+	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
+						    GPIOD_OUT_HIGH);
+	if (IS_ERR(sensor->pwdn_gpio))
+		return PTR_ERR(sensor->pwdn_gpio);
+
+	/* request optional reset pin */
+	sensor->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+						     GPIOD_OUT_HIGH);
+	if (IS_ERR(sensor->reset_gpio))
+		return PTR_ERR(sensor->reset_gpio);
+
+	sensor->regmap = devm_regmap_init_i2c(client, &ovm6211_regmap_config);
+	if (IS_ERR(sensor->regmap)) {
+		dev_err(dev, "regmap init failed\n");
+		return PTR_ERR(sensor->regmap);
+	}
+
+	v4l2_i2c_subdev_init(&sensor->sd, client, &ovm6211_subdev_ops);
+
+	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
+			    V4L2_SUBDEV_FL_HAS_EVENTS;
+	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
+	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
+	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
+	if (ret)
+		return ret;
+
+	ret = ovm6211_get_regulators(sensor);
+	if (ret)
+		return ret;
+
+	ret = ovm6211_set_power(&sensor->sd, 1);
+	if (ret)
+		return ret;
+
+	mutex_init(&sensor->lock);
+
+	ret = ovm6211_check_chip_id(sensor);
+	if (ret)
+		goto entity_cleanup;
+
+	ret = ovm6211_init_controls(sensor);
+	if (ret)
+		goto entity_cleanup;
+
+	ret = v4l2_async_register_subdev_sensor(&sensor->sd);
+	if (ret)
+		goto free_ctrls;
+
+	ovm6211_load_regs(sensor, ovm6211_mode_init_data);
+
+	dev_dbg(dev, "%s() completed\n", __func__);
+	return 0;
+
+free_ctrls:
+	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
+entity_cleanup:
+	media_entity_cleanup(&sensor->sd.entity);
+	mutex_destroy(&sensor->lock);
+	return ret;
+}
+
+static int ovm6211_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
+
+	v4l2_async_unregister_subdev(&sensor->sd);
+	media_entity_cleanup(&sensor->sd.entity);
+	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
+	mutex_destroy(&sensor->lock);
+
+	return 0;
+}
+
+static const struct i2c_device_id ovm6211_id[] = {
+	{ "ovm6211", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, ovm6211_id);
+
+static const struct of_device_id ovm6211_dt_ids[] = {
+	{ .compatible = "ovti,ovm6211" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ovm6211_dt_ids);
+
+static struct i2c_driver ovm6211_i2c_driver = {
+	.driver = {
+		.name  = "ovm6211",
+		.of_match_table	= ovm6211_dt_ids,
+	},
+	.id_table = ovm6211_id,
+	.probe_new = ovm6211_probe,
+	.remove   = ovm6211_remove,
+};
+
+module_i2c_driver(ovm6211_i2c_driver);
+
+MODULE_AUTHOR("Petko Manolov <petko.manolov@konsulko.com>");
+MODULE_DESCRIPTION("OVM6211 MIPI Camera Subdev Driver");
+MODULE_LICENSE("GPL");
-- 
2.30.2

Re: [RFC PATCH 1/5] adds ovm6211 driver to staging

[Sakari Ailus]

Hi Petko,

Thanks for the patchset.

You can squash the other patches into this one (Kconfig and Makefile
changes).

Could you also add DT bindings (and CC Rob Herring and the devicetree list)
in the future?

On Sat, Dec 04, 2021 at 12:12:43AM +0200, Petko Manolov wrote:

Please add some more description, i.e. not just the subject line.

> Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
> ---
>  drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++

Why are you targetting the staging tree? We have a number of sensor drivers
in the kernel proper already.

>  1 file changed, 1156 insertions(+)
>  create mode 100644 drivers/staging/media/i2c/ovm6211.c
> 
> diff --git a/drivers/staging/media/i2c/ovm6211.c b/drivers/staging/media/i2c/ovm6211.c
> new file mode 100644
> index 000000000000..a89c5167a892
> --- /dev/null
> +++ b/drivers/staging/media/i2c/ovm6211.c
> @@ -0,0 +1,1156 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Based on ov5640.c that lives in the same directory.

But we don't have drivers/staging/media/i2c yet?

> + *
> + * Copyright (C) 2021 Petko Manolov <petko.manolov@konsulko.com>
> + * Copyright (C) 2021 DEKA Research & Development Corp.
> + */
> +
> +#define	DEBUG

Is this still meant to be here?

> +
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/clkdev.h>
> +#include <linux/ctype.h>

Do you need all the headers here?

> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/of_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-fwnode.h>
> +#include <media/v4l2-subdev.h>
> +
> +/* Min/max system clock (xvclk) frequencies */
> +#define OVM6211_XVCLK_MIN	 6000000
> +#define OVM6211_XVCLK_MAX	27000000
> +
> +/* begin of OVM6211 definitions */
> +/* System Control */
> +#define OVM6211_SC_MODE_SELECT		0x0100
> +#define OVM6211_SC_SOFTWARE_RESET	0x0103
> +#define OVM6211_SC_SCCB_ID1		0x0109
> +#define OVM6211_SC_CHIP_ID_HIGH		0x300a
> +#define OVM6211_SC_CHIP_ID_LOW		0x300b
> +#define OVM6211_SC_REG0C		0x300c
> +#define OVM6211_SC_REG10		0x3010
> +#define OVM6211_SC_MIPI_PHY		0x3012
> +#define OVM6211_SC_MIPI_PHY2		0x3013
> +#define OVM6211_SC_MIPI_SC_CTRL0	0x3014
> +#define OVM6211_SC_MIPI_SC_CTRL1	0x3015
> +#define OVM6211_SC_CLKRST0		0x3016
> +#define OVM6211_SC_CLKRST1		0x3017
> +#define OVM6211_SC_CLKRST2		0x3018
> +#define OVM6211_SC_CLKRST3		0x3019
> +#define OVM6211_SC_CLKRST4		0x301a
> +#define OVM6211_SC_CLKRST5		0x301b
> +#define OVM6211_SC_CLKRST6		0x301c
> +#define OVM6211_SC_CLOCK_SEL		0x301e
> +#define OVM6211_SC_MISC_CTRL		0x301f
> +#define OVM6211_SC_LOW_PWR_CTRL		0x3023
> +#define OVM6211_SC_REG27		0x3027
> +#define OVM6211_SC_GP_IO_IN1		0x3029
> +#define OVM6211_SC_GP_IO_IN2		0x302a
> +#define OVM6211_SC_SCCB_ID2		0x302b
> +#define OVM6211_SC_AUTO_SLEEP_PERIOD0	0x302c
> +#define OVM6211_SC_AUTO_SLEEP_PERIOD1	0x302d
> +#define OVM6211_SC_AUTO_SLEEP_PERIOD2	0x302e
> +#define OVM6211_SC_AUTO_SLEEP_PERIOD3	0x302f
> +#define OVM6211_SC_LP_CTRL0		0x3030
> +#define OVM6211_SC_REG37		0x3037
> +#define OVM6211_SC_REG3B		0x303b
> +/* PLL Control */
> +#define OVM6211_PLL_PLL0		0x3080
> +#define OVM6211_PLL_PLL1		0x3081
> +#define OVM6211_PLL_PLL2		0x3082
> +#define OVM6211_PLL_PLL18		0x3098
> +#define OVM6211_PLL_PLL19		0x3099
> +#define OVM6211_PLL_PLL1A		0x309a
> +#define OVM6211_PLL_PLL1B		0x309b
> +#define OVM6211_PLL_PLL1C		0x309c
> +#define OVM6211_PLL_PLL1D		0x309d
> +#define OVM6211_PLL_PLL1E		0x309e
> +#define OVM6211_PLL_PLL1F		0x309f
> +#define OVM6211_PLL_VT_PIX_CLK_DIV	0x30b0
> +#define OVM6211_PLL_VT_SYS_CLK_DIV	0x30b1
> +#define OVM6211_PLL_MULTIPLIER		0x30b3
> +#define OVM6211_PLL_PLL1_PRE_PLL_DIV	0x30b4
> +#define OVM6211_PLL_PLL1_OP_PIX_CLK_DIV	0x30b5
> +#define OVM6211_PLL_PLL1_OP_SYS_CLK_DIV	0x30b6
> +/* SCCB and group hold */
> +#define OVM6211_SB_SRB_CTRL		0x3106
> +#define OVM6211_SB_SWITCH		0x31ff
> +/* AEC/AGC */
> +#define OVM6211_AEC_EXPO1		0x3500
> +#define OVM6211_AEC_EXPO2		0x3501
> +#define OVM6211_AEC_EXPO3		0x3502
> +#define OVM6211_AEC_MANUAL		0x3503
> +#define OVM6211_AGC_MAN_SNR_GAIN1	0x3504
> +#define OVM6211_AGC_MAN_SNR_GAIN2	0x3505
> +/* timing conrol registers */
> +#define	OVM6211_TVTS_HI			0x380e
> +#define	OVM6211_TVTS_LO			0x380f
> +/*Strobe frame span registers*/
> +#define OVM6211_STROBE_SPAN1		0x3b8d
> +#define OVM6211_STROBE_SPAN2		0x3b8e
> +#define OVM6211_STROBE_SPAN3		0x3b8f
> +/* format control */
> +#define OVM6211_DATA_MAX_H		0x4300
> +#define OVM6211_DATA_MIN_H		0x4301
> +#define OVM6211_CLIP_L			0x4302
> +#define OVM6211_FORMAT_CTRL3		0x4303
> +#define OVM6211_FORMAT_CTRL4		0x4304
> +#define OVM6211_VSYNC_WIDTH_H		0x4311
> +#define OVM6211_VSYNC_WIDTH_L		0x4312
> +#define OVM6211_VSYNC_CTRL		0x4313
> +#define OVM6211_VSYNC_DELAY1		0x4314
> +#define OVM6211_VSYNC_DELAY2		0x4315
> +#define OVM6211_VSYNC_DELAY3		0x4316
> +#define OVM6211_TST_PATTERN_CTRL	0x4320
> +/* MIPI */
> +#define OVM6211_MIPI_CTRL00		0x4800
> +#define OVM6211_MIPI_CTRL01		0x4801
> +#define OVM6211_MIPI_CTRL02		0x4802
> +#define OVM6211_MIPI_CTRL03		0x4803
> +#define OVM6211_MIPI_CTRL04		0x4804
> +#define OVM6211_MIPI_CTRL05		0x4805
> +#define OVM6211_MIPI_CTRL06		0x4806
> +#define OVM6211_MIPI_MAX_FRAME_COUNT_H	0x4810
> +#define OVM6211_MIPI_MAX_FRAME_COUNT_L	0x4811
> +#define OVM6211_MIPI_SHORT_PKT_COUNTER_H	0x4812
> +#define OVM6211_MIPI_SHORT_PKT_COUNTER_L	0x4813
> +#define OVM6211_MIPI_CTRL14		0x4814
> +#define OVM6211_MIPI_DT_SPKT		0x4815
> +#define OVM6211_MIPI_REG_MAX_H		0x4835
> +#define OVM6211_MIPI_REG_MAX_L		0x4836
> +#define OVM6211_PCLK_PERIOD		0x4837
> +#define OVM6211_WKUP_DLY		0x4838
> +#define OVM6211_DIR_DLY			0x483a
> +#define OVM6211_MIPI_LP_GPIO		0x483b
> +#define OVM6211_MIPI_CTRL3C		0x483c
> +#define OVM6211_T_TA_GO			0x483d
> +#define OVM6211_T_TA_SURE		0x483e
> +#define OVM6211_T_TA_GET		0x483f
> +#define OVM6211_MIPI_CLIP_MAX_H		0x4846
> +#define OVM6211_MIPI_CLIP_MAX_L		0x4847
> +#define OVM6211_MIPI_CLIP_MIN_H		0x4848
> +#define OVM6211_MIPI_CLIP_MIN_L		0x4848
> +#define OVM6211_REG_INTR_MAN		0x4850
> +#define OVM6211_REG_TX_WR		0x4851
> +/* ISP top */
> +#define OVM6211_ISP_CTRL00		0x5000
> +#define OVM6211_ISP_CTRL01		0x5001
> +#define OVM6211_ISP_CTRL02		0x5002
> +#define OVM6211_ISP_CTRL03		0x5003
> +#define OVM6211_ISP_CTRL04		0x5004
> +#define OVM6211_ISP_CTRL05		0x5005
> +#define OVM6211_ISP_CTRL06		0x5006
> +#define OVM6211_ISP_CTRL07		0x5007
> +#define OVM6211_ISP_CTRL08		0x5008
> +#define OVM6211_ISP_CTRL09		0x5009
> +/* window control */
> +#define OVM6211_MAN_XSTART_OFF_H	0x5a00
> +#define OVM6211_MAN_XSTART_OFF_L	0x5a01
> +#define OVM6211_MAN_YSTART_OFF_H	0x5a02
> +#define OVM6211_MAN_YSTART_OFF_L	0x5a03
> +#define OVM6211_MAN_WIN_WIDTH_H		0x5a04
> +#define OVM6211_MAN_WIN_WIDTH_L		0x5a05
> +#define OVM6211_MAN_WIN_HEIGHT_H	0x5a06
> +#define OVM6211_MAN_WIN_HEIGHT_L	0x5a07
> +#define OVM6211_WIN_MAN			0x5a08
> +
> +#define	OVM6211_LAST_REG		0x5e08
> +/* end of OVM6211 definitions */
> +
> +enum ovm6211_mode_id {
> +	OVM6211_MODE_Y8_400_200 = 0,
> +	OVM6211_MODE_Y8_400_400,
> +	OVM6211_NUM_MODES,
> +};
> +
> +struct ovm6211_pixfmt {
> +	u32 code;
> +	u32 colorspace;
> +};
> +
> +static const struct ovm6211_pixfmt ovm6211_formats[] = {
> +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> +};
> +
> +enum ovm6211_framerate_ids {
> +	OVM6211_10_FPS = 0,
> +	OVM6211_15_FPS,
> +	OVM6211_30_FPS,
> +	OVM6211_45_FPS,
> +	OVM6211_60_FPS,
> +	OVM6211_NUM_FRAMERATES,
> +};
> +
> +static const int ovm6211_framerates[] = {
> +	[OVM6211_10_FPS] = 10,
> +	[OVM6211_15_FPS] = 15,
> +	[OVM6211_30_FPS] = 30,
> +	[OVM6211_45_FPS] = 45,
> +	[OVM6211_60_FPS] = 60,
> +};
> +
> +/* regulator supplies */
> +static const char * const ovm6211_supply_name[] = {
> +	"dovdd",
> +	"avdd",
> +};
> +
> +#define OVM6211_NUM_SUPPLIES ARRAY_SIZE(ovm6211_supply_name)

I'd suggest to use plain ARRAY_SIZE() instead. This is just an unnecessary
macro.

> +
> +static const struct regmap_config ovm6211_regmap_config = {
> +	.reg_bits       = 16,
> +	.val_bits       = 8,
> +	.max_register   = OVM6211_LAST_REG,
> +	.cache_type	= REGCACHE_NONE,
> +};
> +
> +struct reg_value {
> +	u16 reg_addr;
> +	u8 val;
> +	u8 mask;
> +	u32 delay_ms;
> +};
> +
> +struct ovm6211_mode_info {
> +	enum ovm6211_mode_id id;
> +	u32 width;
> +	u32 height;
> +	const struct reg_value *reg_data;
> +	u32 reg_data_size;
> +	u32 pixel_clock;
> +};
> +
> +struct ovm6211_ctrls {
> +	struct v4l2_ctrl_handler handler;
> +	struct {
> +		struct v4l2_ctrl *auto_exp;
> +		struct v4l2_ctrl *exposure;
> +	};
> +	struct {
> +		struct v4l2_ctrl *auto_gain;
> +		struct v4l2_ctrl *gain;
> +	};
> +	struct v4l2_ctrl *brightness;
> +	struct v4l2_ctrl *light_freq;
> +	struct v4l2_ctrl *saturation;
> +	struct v4l2_ctrl *contrast;
> +	struct v4l2_ctrl *hue;
> +	struct v4l2_ctrl *test_pattern;
> +	struct v4l2_ctrl *link_freq;
> +	struct v4l2_ctrl *pixel_clock;
> +};
> +
> +struct ovm6211_dev {
> +	struct i2c_client *i2c_client;
> +	struct regmap *regmap;
> +	struct v4l2_subdev sd;
> +	struct media_pad pad;
> +	struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
> +	struct clk *xclk; /* system clock to OVM6211 */
> +	u32 xclk_freq;
> +
> +	struct regulator_bulk_data supplies[OVM6211_NUM_SUPPLIES];
> +	struct gpio_desc *reset_gpio;
> +	struct gpio_desc *pwdn_gpio;
> +
> +	struct mutex lock;
> +
> +	struct v4l2_mbus_framefmt fmt;
> +
> +	const struct ovm6211_mode_info *cur_mode;
> +	enum ovm6211_framerate_ids cur_fr_id;
> +	struct v4l2_fract frame_interval;
> +
> +	struct ovm6211_ctrls ctrls;
> +
> +	u32 exposure;
> +	bool pending_mode_change;
> +	bool pending_fi_change;
> +	bool streaming;
> +};
> +
> +static inline struct ovm6211_dev *to_ovm6211_dev(struct v4l2_subdev *sd)
> +{
> +	return container_of(sd, struct ovm6211_dev, sd);
> +}
> +
> +static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
> +{
> +	return &container_of(ctrl->handler, struct ovm6211_dev,
> +			     ctrls.handler)->sd;
> +}
> +
> +static const struct reg_value ovm6211_init_y8_400_400[] = {
> +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0}, {0x3808, 0x01, 0, 0},
> +	{0x3809, 0x90, 0, 0}, {0x380a, 0x01, 0, 0}, {0x380b, 0x90, 0, 0},
> +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x03, 0, 0},
> +	{0x380f, 0x6c, 0, 0}, {0x3810, 0x00, 0, 0}, {0x3811, 0x04, 0, 0},
> +	{0x3812, 0x00, 0, 0}, {0x3813, 0x04, 0, 0}, {0x3814, 0x11, 0, 0},
> +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> +};
> +
> +static const struct reg_value ovm6211_init_y8_400_200[] = {
> +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0},
> +	{0x3808, 0x01, 0, 0},	// W
> +	{0x3809, 0x90, 0, 0},	// W
> +	{0x380a, 0x00, 0, 0},	// H
> +	{0x380b, 0xc8, 0, 0},	// H
> +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x0d, 0, 0},
> +	{0x380f, 0xb0, 0, 0},
> +	{0x3810, 0x00, 0, 0},	// W off
> +	{0x3811, 0x04, 0, 0},	// W off: 4 + (400 - x_width)/2
> +	{0x3812, 0x00, 0, 0},	// H off
> +	{0x3813, 0x9a, 0, 0},	// H off: 4 + (400 - y_height)/2
> +	{0x3814, 0x11, 0, 0},
> +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> +};
> +
> +/* power-on sensor init reg table */
> +static const struct ovm6211_mode_info *ovm6211_mode_init_data;
> +
> +static struct ovm6211_mode_info
> +ovm6211_mode_data[OVM6211_NUM_MODES] = {
> +	{OVM6211_MODE_Y8_400_200,
> +	 400, 200,
> +	 ovm6211_init_y8_400_200,
> +	 ARRAY_SIZE(ovm6211_init_y8_400_200),
> +	 400 * 400 * 60 * 2,
> +	},
> +	{OVM6211_MODE_Y8_400_400,
> +	 400, 400,
> +	 ovm6211_init_y8_400_400,
> +	 ARRAY_SIZE(ovm6211_init_y8_400_400),
> +	 400 * 400 * 60 * 2,
> +	},
> +};
> +
> +static const s64 link_freq_menu_items[] = {
> +	0,
> +};
> +
> +#ifdef CONFIG_VIDEO_ADV_DEBUG
> +static int ovm6211_get_register(struct v4l2_subdev *sd,
> +				struct v4l2_dbg_register *reg)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	struct regmap *regmap = sensor->regmap;
> +	unsigned int val = 0;
> +	int ret;
> +
> +	ret = regmap_read(regmap, reg->reg, &val);
> +	reg->val = val;
> +	reg->size = 1;
> +
> +	return ret;
> +}
> +
> +static int ovm6211_set_register(struct v4l2_subdev *sd,
> +				const struct v4l2_dbg_register *reg)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	struct regmap *regmap = sensor->regmap;
> +
> +	return regmap_write(regmap, reg->reg, reg->val & 0xff);
> +}
> +#endif
> +
> +static int ovm6211_write_reg(struct ovm6211_dev *sensor, u16 reg, u8 val)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct regmap *regmap = sensor->regmap;
> +	int ret;
> +
> +	ret = regmap_write(regmap, reg, val);
> +	if (ret < 0)
> +		dev_err(&client->dev, "error writing reg %u\n", reg);
> +
> +	return ret;
> +}
> +
> +static int ovm6211_read_reg(struct ovm6211_dev *sensor, u16 reg, u8 *val)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct regmap *regmap = sensor->regmap;
> +	unsigned int r;
> +	int ret;
> +
> +	ret = regmap_read(regmap, reg, &r);
> +	if (ret < 0)
> +		dev_err(&client->dev, "error reading reg %u\n", reg);
> +	*val = r & 0xff;
> +
> +	return ret;
> +}
> +
> +static int ovm6211_mod_reg(struct ovm6211_dev *sensor, u16 reg, u8 mask, u8 val)
> +{
> +	u8 readval;
> +	int ret;
> +
> +	ret = ovm6211_read_reg(sensor, reg, &readval);
> +	if (ret)
> +		return ret;
> +
> +	readval &= ~mask;
> +	val &= mask;
> +	val |= readval;
> +
> +	return ovm6211_write_reg(sensor, reg, val);
> +}
> +
> +static int ovm6211_load_regs(struct ovm6211_dev *sensor,
> +			     const struct ovm6211_mode_info *mode)
> +{
> +	const struct reg_value *regs = mode->reg_data;
> +	unsigned int i;
> +	u32 delay_ms;
> +	u16 reg_addr;
> +	u8 mask, val;
> +	int ret = 0;
> +
> +	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
> +		delay_ms = regs->delay_ms;
> +		reg_addr = regs->reg_addr;
> +		val = regs->val;
> +		mask = regs->mask;
> +		if (mask)
> +			ret = ovm6211_mod_reg(sensor, reg_addr, mask, val);
> +		else
> +			ret = ovm6211_write_reg(sensor, reg_addr, val);
> +		if (ret)
> +			break;
> +
> +		if (delay_ms) {
> +			usleep_range(1000 * delay_ms, 1000 * delay_ms + 100);
> +		}
> +	}
> +
> +	return ret;
> +}
> +
> +static void ovm6211_soft_reset(struct ovm6211_dev *sensor)
> +{
> +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x01);
> +	usleep_range(5000, 9000);
> +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x00);
> +}
> +
> +static int ovm6211_set_exposure(struct ovm6211_dev *sensor, u32 exposure)
> +{
> +	u32 ce;
> +	u8 v;
> +
> +	ovm6211_read_reg(sensor, OVM6211_TVTS_HI, &v);
> +	ce = v << 8;
> +	ovm6211_read_reg(sensor, OVM6211_TVTS_LO, &v);
> +	ce |= v;
> +	ce -= 4;
> +
> +	if (ce < exposure)
> +		exposure = ce;
> +
> +	ovm6211_mod_reg(sensor, OVM6211_AEC_MANUAL, 1, 1);
> +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO1, (exposure >> 12) & 0x0f);
> +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO2, (exposure >>  4) & 0xff);
> +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO3, (exposure <<  4) & 0xf0);
> +
> +	/* set strobe width equal to exposure time */
> +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN1, (exposure >> 16) & 0xff);
> +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN2, (exposure >>  8) & 0xff);
> +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN3, (exposure)       & 0xff);
> +
> +	return 0;
> +}
> +
> +static int internal_set_stream(struct ovm6211_dev *sensor, bool on)
> +{
> +	u8 hi, lo;
> +
> +	if (sensor->pending_fi_change == false)
> +		goto stream;
> +
> +	switch (sensor->cur_fr_id) {
> +	case OVM6211_10_FPS:
> +		hi = 0x14;
> +		lo = 0x88;
> +		break;
> +	case OVM6211_15_FPS:
> +		hi = 0x0d;
> +		lo = 0xb0;
> +		break;
> +	case OVM6211_30_FPS:
> +		hi = 0x06;
> +		lo = 0xd8;
> +		break;
> +	case OVM6211_45_FPS:
> +		hi=0x04;

Spaces around '=', please.

> +		lo = 0x90;
> +		break;
> +	case OVM6211_60_FPS:
> +		hi=0x03;
> +		lo = 0x6c;
> +		break;
> +	case OVM6211_NUM_FRAMERATES:
> +		return -EINVAL;
> +	}
> +
> +	sensor->pending_fi_change = false;
> +	ovm6211_write_reg(sensor, OVM6211_TVTS_HI, hi);
> +	ovm6211_write_reg(sensor, OVM6211_TVTS_LO, lo);
> +stream:
> +	ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 0);
> +	if (on) {
> +		usleep_range(4000, 5000);
> +		if (sensor->exposure)
> +			ovm6211_set_exposure(sensor, sensor->exposure);
> +		ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 1);
> +		sensor->streaming = true;
> +	} else {
> +		sensor->streaming = false;
> +	}
> +
> +	return 0;
> +}
> +
> +static struct ovm6211_mode_info *ovm6211_find_mode(int w, int h)
> +{
> +	return v4l2_find_nearest_size(ovm6211_mode_data,
> +				      ARRAY_SIZE(ovm6211_mode_data),
> +				      width, height, w, h);
> +}
> +
> +static int ovm6211_set_mode(struct ovm6211_dev *sensor)
> +{
> +	const struct ovm6211_mode_info *mode = sensor->cur_mode;
> +
> +	ovm6211_soft_reset(sensor);
> +	ovm6211_load_regs(sensor, mode);
> +
> +	return 0;
> +}
> +
> +/* --------------- Subdev Operations --------------- */
> +
> +static int ovm6211_get_fmt(struct v4l2_subdev *sd,
> +			   struct v4l2_subdev_state *state,
> +			   struct v4l2_subdev_format *format)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	struct v4l2_mbus_framefmt *fmt;
> +
> +	if (format->pad != 0)
> +		return -EINVAL;
> +
> +	mutex_lock(&sensor->lock);
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> +		format->format = *fmt;
> +	} else {
> +		/* these are hardcoded as we don't support anything else */
> +		format->format.colorspace  = V4L2_COLORSPACE_RAW;
> +		format->format.field = V4L2_FIELD_NONE;
> +		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> +		format->format.width = sensor->cur_mode->width;
> +		format->format.height = sensor->cur_mode->height;
> +	}
> +
> +	mutex_unlock(&sensor->lock);
> +
> +	return 0;
> +}
> +
> +u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
> +{
> +	u32 s, fmt, fps, ret;
> +
> +	/* x * y * [1|2] * y8/y10 * fps */
> +	s = nm->width * nm->height;
> +	fmt = 1;
> +	fps = ovm6211_framerates[sensor->cur_fr_id];
> +	ret = s * fmt * fps * 2;
> +
> +	return ret;
> +}
> +
> +static int ovm6211_set_fmt(struct v4l2_subdev *sd,
> +			   struct v4l2_subdev_state *state,
> +			   struct v4l2_subdev_format *format)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	struct v4l2_mbus_framefmt *fmt = &format->format;
> +	struct ovm6211_mode_info *mode;
> +
> +	if (format->pad != 0)
> +		return -EINVAL;
> +
> +	if (sensor->streaming)
> +		return -EBUSY;
> +
> +	mutex_lock(&sensor->lock);
> +
> +	/* these are hardcoded as we don't support anything else */
> +	format->format.colorspace  = V4L2_COLORSPACE_RAW;
> +	format->format.field = V4L2_FIELD_NONE;
> +	format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> +	mode = ovm6211_find_mode(format->format.width, format->format.height);
> +	format->format.width = mode->width;
> +	format->format.height = mode->height;
> +
> +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> +		*fmt = format->format;
> +		goto out;
> +	}
> +	/* V4L2_SUBDEV_FORMAT_TRY_ACTIVE */
> +	sensor->cur_mode = mode;
> +out:
> +	mutex_unlock(&sensor->lock);
> +
> +	return 0;
> +}
> +
> +/*
> + * Sensor Controls.
> + */
> +
> +static int ovm6211_set_ctrl_exposure(struct ovm6211_dev *sensor, enum
> +				     v4l2_exposure_auto_type auto_exposure)
> +{
> +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> +
> +	if (auto_exposure == V4L2_EXPOSURE_AUTO) {
> +		sensor->exposure = 0;
> +	} else {
> +		sensor->exposure = ctrls->exposure->val;
> +		ovm6211_set_exposure(sensor, sensor->exposure);
> +	}
> +
> +	return 0;
> +}
> +
> +static int ovm6211_set_ctrl_gain(struct ovm6211_dev *sensor, bool auto_gain)
> +{

Hmm. Is something missing here?

> +	return 0;
> +}
> +
> +static int ovm6211_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	int ret;
> +
> +	/* v4l2_ctrl_lock() locks our own mutex */
> +
> +	/*
> +	 * If the device is not powered up by the host driver do
> +	 * not apply any controls to H/W at this time. Instead
> +	 * the controls will be restored right after power-up.
> +	 */
> +	switch (ctrl->id) {
> +	case V4L2_CID_GAIN:
> +		ret = ovm6211_set_ctrl_gain(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_EXPOSURE_AUTO:
> +		ret = ovm6211_set_ctrl_exposure(sensor, ctrl->val);
> +		break;
> +#if 0

Why?

> +	case V4L2_CID_AUTO_WHITE_BALANCE:
> +		ret = ovm6211_set_ctrl_white_balance(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_HUE:
> +		ret = ovm6211_set_ctrl_hue(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_CONTRAST:
> +		ret = ovm6211_set_ctrl_contrast(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_SATURATION:
> +		ret = ovm6211_set_ctrl_saturation(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_TEST_PATTERN:
> +		ret = ovm6211_set_ctrl_test_pattern(sensor, ctrl->val);
> +		break;
> +	case V4L2_CID_POWER_LINE_FREQUENCY:
> +		ret = ovm6211_set_ctrl_light_freq(sensor, ctrl->val);
> +		break;
> +#endif
> +	case V4L2_CID_LINK_FREQ:
> +		return 0;
> +	case V4L2_CID_PIXEL_RATE:
> +		return 0;
> +	default:
> +		ret = -EINVAL;
> +		break;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_ctrl_ops ovm6211_ctrl_ops = {
> +	.s_ctrl = ovm6211_s_ctrl,
> +};
> +
> +static int ovm6211_init_controls(struct ovm6211_dev *sensor)
> +{
> +	const struct v4l2_ctrl_ops *ops = &ovm6211_ctrl_ops;
> +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> +	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
> +	int ret;
> +
> +	v4l2_ctrl_handler_init(hdl, 32);

This number should be more or less the number of controls.

> +
> +	/* we can use our own mutex for the ctrl lock */
> +	hdl->lock = &sensor->lock;
> +
> +	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_EXPOSURE_AUTO,
> +						 V4L2_EXPOSURE_MANUAL, 0,
> +						 V4L2_EXPOSURE_AUTO);
> +	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
> +					    0, 65535, 1, 0);
> +	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN,
> +					0, 1023, 1, 0);
> +
> +	v4l2_ctrl_auto_cluster(3, &ctrls->auto_exp, 0, false);
> +
> +	ctrls->saturation = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION,
> +					      0, 255, 1, 64);
> +	ctrls->hue = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HUE,
> +				       0, 359, 1, 0);
> +	ctrls->contrast = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST,
> +					    0, 255, 1, 0);
> +	ctrls->light_freq =
> +		v4l2_ctrl_new_std_menu(hdl, ops,
> +				       V4L2_CID_POWER_LINE_FREQUENCY,
> +				       V4L2_CID_POWER_LINE_FREQUENCY_AUTO, 0,
> +				       V4L2_CID_POWER_LINE_FREQUENCY_50HZ);
> +	ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
> +						  0, 0, link_freq_menu_items);
> +	ctrls->pixel_clock = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
> +						    1, INT_MAX, 1, 38400000);
> +
> +	if (hdl->error) {
> +		ret = hdl->error;
> +		goto free_ctrls;
> +	}
> +
> +	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
> +	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
> +
> +	sensor->sd.ctrl_handler = hdl;
> +	return 0;
> +
> +free_ctrls:
> +	v4l2_ctrl_handler_free(hdl);
> +	return ret;
> +}
> +
> +static int ovm6211_g_frame_interval(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_frame_interval *fi)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +
> +	mutex_lock(&sensor->lock);
> +	fi->interval = sensor->frame_interval;
> +	mutex_unlock(&sensor->lock);
> +
> +	return 0;
> +}
> +
> +static int internal_set_frame_interval(struct ovm6211_dev *sensor, struct
> +				       v4l2_subdev_frame_interval *fi)
> +{
> +	u32 fr_rate;
> +	int i, max, ret = -EINVAL;
> +
> +	if (fi->interval.numerator == 0)
> +		goto out;
> +
> +	fr_rate = fi->interval.denominator / fi->interval.numerator;
> +
> +	max = ARRAY_SIZE(ovm6211_framerates);
> +	for (i = 0; i < max; i++) {
> +		if (ovm6211_framerates[i] == fr_rate)
> +			break;
> +	}
> +
> +	if (i == max)
> +		goto out;
> +
> +	sensor->cur_fr_id = i;
> +	sensor->frame_interval = fi->interval;
> +	ret = 0;
> +out:
> +	return ret;
> +}
> +
> +static int ovm6211_s_frame_interval(struct v4l2_subdev *sd,
> +				    struct v4l2_subdev_frame_interval *fi)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	int ret;
> +
> +	mutex_lock(&sensor->lock);
> +	ret = internal_set_frame_interval(sensor, fi);
> +	sensor->pending_fi_change = true;
> +	mutex_unlock(&sensor->lock);
> +
> +	return ret;
> +}
> +
> +static int ovm6211_enum_mbus_code(struct v4l2_subdev *sd,
> +				  struct v4l2_subdev_state *state,
> +				  struct v4l2_subdev_mbus_code_enum *code)
> +{
> +	if (code->pad != 0)
> +		return -EINVAL;

This check can be dropped, the caller has done it already (I assume you
have a single pad).

> +	if (code->index >= ARRAY_SIZE(ovm6211_formats))
> +		return -EINVAL;
> +
> +	code->code = ovm6211_formats[code->index].code;
> +
> +	return 0;
> +}
> +
> +static int ovm6211_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +	int ret = 0;
> +
> +	mutex_lock(&sensor->lock);
> +
> +	if (enable)
> +		ret = ovm6211_set_mode(sensor);
> +	internal_set_stream(sensor, enable);
> +
> +	mutex_unlock(&sensor->lock);
> +
> +	return ret;
> +}
> +
> +static int ovm6211_set_power(struct v4l2_subdev *sd, int on)
> +{
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_core_ops ovm6211_core_ops = {
> +#ifdef CONFIG_VIDEO_ADV_DEBUG
> +	.g_register = ovm6211_get_register,
> +	.s_register = ovm6211_set_register,
> +#endif
> +	.s_power = ovm6211_set_power,
> +};
> +
> +static const struct v4l2_subdev_video_ops ovm6211_video_ops = {
> +	.g_frame_interval = ovm6211_g_frame_interval,
> +	.s_frame_interval = ovm6211_s_frame_interval,
> +	.s_stream = ovm6211_s_stream,
> +};
> +
> +static const struct v4l2_subdev_pad_ops ovm6211_pad_ops = {
> +	.enum_mbus_code = ovm6211_enum_mbus_code,
> +	.get_fmt = ovm6211_get_fmt,
> +	.set_fmt = ovm6211_set_fmt,
> +};
> +
> +static const struct v4l2_subdev_ops ovm6211_subdev_ops = {
> +	.core = &ovm6211_core_ops,
> +	.video = &ovm6211_video_ops,
> +	.pad = &ovm6211_pad_ops,
> +};
> +
> +static int ovm6211_get_regulators(struct ovm6211_dev *sensor)
> +{
> +	int i;

unsigned int, please.

> +
> +	for (i = 0; i < OVM6211_NUM_SUPPLIES; i++)
> +		sensor->supplies[i].supply = ovm6211_supply_name[i];
> +
> +	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
> +				       OVM6211_NUM_SUPPLIES,
> +				       sensor->supplies);
> +}
> +
> +static int ovm6211_check_chip_id(struct ovm6211_dev *sensor)
> +{
> +	struct i2c_client *client = sensor->i2c_client;
> +	struct regmap *regmap = sensor->regmap;
> +	unsigned int cid;
> +	int ret = 0;
> +
> +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_HIGH, &cid);
> +	if (ret || cid != 0x67) {
> +		ret = ENXIO;
> +		goto err;
> +	}
> +
> +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_LOW, &cid);
> +	if (ret || cid != 0x10) {
> +		ret = -ENXIO;
> +		goto err;
> +	}
> +
> +	ret = regmap_read(regmap, OVM6211_SC_REG0C, &cid);
> +	if (ret)
> +		goto err;
> +
> +	dev_info(&client->dev,"found OVM6211, sub revision: 0x%02X\n", cid);
> +	return 0;
> +err:
> +	dev_err(&client->dev, "failed to detect OVM6211\n");
> +	return ret;
> +}
> +
> +static int ovm6211_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct fwnode_handle *endpoint;
> +	struct ovm6211_dev *sensor;
> +	struct v4l2_mbus_framefmt *fmt;
> +	int ret;
> +
> +	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
> +	if (!sensor)
> +		return -ENOMEM;
> +
> +	sensor->i2c_client = client;
> +
> +	/*
> +	 * default init sequence initialize sensor to
> +	 * YUV422 UYVY VGA@30fps
> +	 */
> +	fmt = &sensor->fmt;
> +	fmt->code = MEDIA_BUS_FMT_Y8_1X8;
> +	fmt->colorspace = V4L2_COLORSPACE_RAW;
> +	fmt->field = V4L2_FIELD_NONE;
> +	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> +	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> +	fmt->width = 400;
> +	fmt->height = 200;
> +
> +	sensor->frame_interval.numerator = 1;
> +	sensor->frame_interval.denominator = ovm6211_framerates[OVM6211_45_FPS];
> +	sensor->cur_fr_id = OVM6211_45_FPS;
> +	ovm6211_mode_init_data = &ovm6211_mode_data[OVM6211_MODE_Y8_400_200];
> +	sensor->cur_mode = ovm6211_mode_init_data;
> +
> +	sensor->ep.bus_type = V4L2_MBUS_CSI2_DPHY;
> +	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);

Over 80, please wrap. Same for other such lines (maybe apart from tables
etc.).

> +	if (!endpoint) {
> +		dev_err(dev, "endpoint node not found\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = v4l2_fwnode_endpoint_parse(endpoint, &sensor->ep);
> +	fwnode_handle_put(endpoint);
> +	if (ret) {
> +		dev_err(dev, "Could not parse endpoint\n");
> +		return ret;
> +	}
> +
> +	/* get system clock (xclk) */
> +	sensor->xclk = devm_clk_get(dev, "xvclk");

This driver seems to be based on register lists. Which xvclk frequency are
they for?

> +	if (IS_ERR(sensor->xclk)) {
> +		dev_err(dev, "failed to get xvclk\n");
> +		return PTR_ERR(sensor->xclk);
> +	}
> +
> +	sensor->xclk_freq = clk_get_rate(sensor->xclk);
> +	if (sensor->xclk_freq < OVM6211_XVCLK_MIN ||
> +	    sensor->xclk_freq > OVM6211_XVCLK_MAX) {
> +		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
> +			sensor->xclk_freq);
> +		return -EINVAL;
> +	}
> +
> +	/* request optional power down pin */
> +	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
> +						    GPIOD_OUT_HIGH);
> +	if (IS_ERR(sensor->pwdn_gpio))
> +		return PTR_ERR(sensor->pwdn_gpio);
> +
> +	/* request optional reset pin */
> +	sensor->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> +						     GPIOD_OUT_HIGH);
> +	if (IS_ERR(sensor->reset_gpio))
> +		return PTR_ERR(sensor->reset_gpio);
> +
> +	sensor->regmap = devm_regmap_init_i2c(client, &ovm6211_regmap_config);
> +	if (IS_ERR(sensor->regmap)) {
> +		dev_err(dev, "regmap init failed\n");
> +		return PTR_ERR(sensor->regmap);
> +	}
> +
> +	v4l2_i2c_subdev_init(&sensor->sd, client, &ovm6211_subdev_ops);
> +
> +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> +	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
> +	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> +	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
> +	if (ret)
> +		return ret;

You'll need to call media_entity_cleanup() after this.

> +
> +	ret = ovm6211_get_regulators(sensor);
> +	if (ret)
> +		return ret;
> +
> +	ret = ovm6211_set_power(&sensor->sd, 1);
> +	if (ret)
> +		return ret;
> +
> +	mutex_init(&sensor->lock);
> +
> +	ret = ovm6211_check_chip_id(sensor);
> +	if (ret)
> +		goto entity_cleanup;
> +
> +	ret = ovm6211_init_controls(sensor);
> +	if (ret)
> +		goto entity_cleanup;
> +
> +	ret = v4l2_async_register_subdev_sensor(&sensor->sd);
> +	if (ret)
> +		goto free_ctrls;
> +
> +	ovm6211_load_regs(sensor, ovm6211_mode_init_data);

Please add support for runtime PM.

I'd suggest to take a look at this as well:

<URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>

> +
> +	dev_dbg(dev, "%s() completed\n", __func__);

Please remove.

> +	return 0;
> +
> +free_ctrls:
> +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> +entity_cleanup:
> +	media_entity_cleanup(&sensor->sd.entity);
> +	mutex_destroy(&sensor->lock);
> +	return ret;
> +}
> +
> +static int ovm6211_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> +
> +	v4l2_async_unregister_subdev(&sensor->sd);
> +	media_entity_cleanup(&sensor->sd.entity);
> +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> +	mutex_destroy(&sensor->lock);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id ovm6211_id[] = {
> +	{ "ovm6211", 0 },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(i2c, ovm6211_id);
> +
> +static const struct of_device_id ovm6211_dt_ids[] = {
> +	{ .compatible = "ovti,ovm6211" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, ovm6211_dt_ids);
> +
> +static struct i2c_driver ovm6211_i2c_driver = {
> +	.driver = {
> +		.name  = "ovm6211",
> +		.of_match_table	= ovm6211_dt_ids,
> +	},
> +	.id_table = ovm6211_id,

Please remove ovm62211_id table unless you really need it.

> +	.probe_new = ovm6211_probe,
> +	.remove   = ovm6211_remove,
> +};
> +
> +module_i2c_driver(ovm6211_i2c_driver);
> +
> +MODULE_AUTHOR("Petko Manolov <petko.manolov@konsulko.com>");
> +MODULE_DESCRIPTION("OVM6211 MIPI Camera Subdev Driver");
> +MODULE_LICENSE("GPL");

-- 
Kind regards,

Sakari Ailus

Re: [RFC PATCH 1/5] adds ovm6211 driver to staging

[Petko Manolov]

On 21-12-07 14:44:14, Sakari Ailus wrote:
> Hi Petko,

Hey Sakari.  I've subscribed to linux-media using my company email address.
Thanks to Google, i found your message in my SPAM folder.  Along with a whole
bunch of other linux-media, linux-kernel and netdev emails.  Not sure what's
wrong with the G men these days...

> Thanks for the patchset.
> 
> You can squash the other patches into this one (Kconfig and Makefile
> changes).
> 
> Could you also add DT bindings (and CC Rob Herring and the devicetree list) in
> the future?

Yup, will do this in parallel with this patch series.

> On Sat, Dec 04, 2021 at 12:12:43AM +0200, Petko Manolov wrote:
> 
> Please add some more description, i.e. not just the subject line.

Uhm, ok.

> > Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
> > ---
> >  drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++
> 
> Why are you targetting the staging tree? We have a number of sensor drivers
> in the kernel proper already.

Because it is a new and relatively untested (by the general public) driver.

> >  1 file changed, 1156 insertions(+)
> >  create mode 100644 drivers/staging/media/i2c/ovm6211.c
> > 
> > diff --git a/drivers/staging/media/i2c/ovm6211.c b/drivers/staging/media/i2c/ovm6211.c
> > new file mode 100644
> > index 000000000000..a89c5167a892
> > --- /dev/null
> > +++ b/drivers/staging/media/i2c/ovm6211.c
> > @@ -0,0 +1,1156 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Based on ov5640.c that lives in the same directory.
> 
> But we don't have drivers/staging/media/i2c yet?
> 
> > + *
> > + * Copyright (C) 2021 Petko Manolov <petko.manolov@konsulko.com>
> > + * Copyright (C) 2021 DEKA Research & Development Corp.
> > + */
> > +
> > +#define	DEBUG
> 
> Is this still meant to be here?

Nope, an omission on my part.

> > +
> > +#include <linux/clk.h>
> > +#include <linux/clk-provider.h>
> > +#include <linux/clkdev.h>
> > +#include <linux/ctype.h>
> 
> Do you need all the headers here?

Seems like the answer is yes, devm_clk_get() and clk_get_rate() definitions come
from these headers.

> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/i2c.h>
> > +#include <linux/init.h>
> > +#include <linux/module.h>
> > +#include <linux/regmap.h>
> > +#include <linux/of_device.h>
> > +#include <linux/regulator/consumer.h>
> > +#include <linux/slab.h>
> > +#include <linux/types.h>
> > +#include <media/v4l2-async.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/v4l2-fwnode.h>
> > +#include <media/v4l2-subdev.h>
> > +
> > +/* Min/max system clock (xvclk) frequencies */
> > +#define OVM6211_XVCLK_MIN	 6000000
> > +#define OVM6211_XVCLK_MAX	27000000
> > +
> > +/* begin of OVM6211 definitions */
> > +/* System Control */
> > +#define OVM6211_SC_MODE_SELECT		0x0100
> > +#define OVM6211_SC_SOFTWARE_RESET	0x0103
> > +#define OVM6211_SC_SCCB_ID1		0x0109
> > +#define OVM6211_SC_CHIP_ID_HIGH		0x300a
> > +#define OVM6211_SC_CHIP_ID_LOW		0x300b
> > +#define OVM6211_SC_REG0C		0x300c
> > +#define OVM6211_SC_REG10		0x3010
> > +#define OVM6211_SC_MIPI_PHY		0x3012
> > +#define OVM6211_SC_MIPI_PHY2		0x3013
> > +#define OVM6211_SC_MIPI_SC_CTRL0	0x3014
> > +#define OVM6211_SC_MIPI_SC_CTRL1	0x3015
> > +#define OVM6211_SC_CLKRST0		0x3016
> > +#define OVM6211_SC_CLKRST1		0x3017
> > +#define OVM6211_SC_CLKRST2		0x3018
> > +#define OVM6211_SC_CLKRST3		0x3019
> > +#define OVM6211_SC_CLKRST4		0x301a
> > +#define OVM6211_SC_CLKRST5		0x301b
> > +#define OVM6211_SC_CLKRST6		0x301c
> > +#define OVM6211_SC_CLOCK_SEL		0x301e
> > +#define OVM6211_SC_MISC_CTRL		0x301f
> > +#define OVM6211_SC_LOW_PWR_CTRL		0x3023
> > +#define OVM6211_SC_REG27		0x3027
> > +#define OVM6211_SC_GP_IO_IN1		0x3029
> > +#define OVM6211_SC_GP_IO_IN2		0x302a
> > +#define OVM6211_SC_SCCB_ID2		0x302b
> > +#define OVM6211_SC_AUTO_SLEEP_PERIOD0	0x302c
> > +#define OVM6211_SC_AUTO_SLEEP_PERIOD1	0x302d
> > +#define OVM6211_SC_AUTO_SLEEP_PERIOD2	0x302e
> > +#define OVM6211_SC_AUTO_SLEEP_PERIOD3	0x302f
> > +#define OVM6211_SC_LP_CTRL0		0x3030
> > +#define OVM6211_SC_REG37		0x3037
> > +#define OVM6211_SC_REG3B		0x303b
> > +/* PLL Control */
> > +#define OVM6211_PLL_PLL0		0x3080
> > +#define OVM6211_PLL_PLL1		0x3081
> > +#define OVM6211_PLL_PLL2		0x3082
> > +#define OVM6211_PLL_PLL18		0x3098
> > +#define OVM6211_PLL_PLL19		0x3099
> > +#define OVM6211_PLL_PLL1A		0x309a
> > +#define OVM6211_PLL_PLL1B		0x309b
> > +#define OVM6211_PLL_PLL1C		0x309c
> > +#define OVM6211_PLL_PLL1D		0x309d
> > +#define OVM6211_PLL_PLL1E		0x309e
> > +#define OVM6211_PLL_PLL1F		0x309f
> > +#define OVM6211_PLL_VT_PIX_CLK_DIV	0x30b0
> > +#define OVM6211_PLL_VT_SYS_CLK_DIV	0x30b1
> > +#define OVM6211_PLL_MULTIPLIER		0x30b3
> > +#define OVM6211_PLL_PLL1_PRE_PLL_DIV	0x30b4
> > +#define OVM6211_PLL_PLL1_OP_PIX_CLK_DIV	0x30b5
> > +#define OVM6211_PLL_PLL1_OP_SYS_CLK_DIV	0x30b6
> > +/* SCCB and group hold */
> > +#define OVM6211_SB_SRB_CTRL		0x3106
> > +#define OVM6211_SB_SWITCH		0x31ff
> > +/* AEC/AGC */
> > +#define OVM6211_AEC_EXPO1		0x3500
> > +#define OVM6211_AEC_EXPO2		0x3501
> > +#define OVM6211_AEC_EXPO3		0x3502
> > +#define OVM6211_AEC_MANUAL		0x3503
> > +#define OVM6211_AGC_MAN_SNR_GAIN1	0x3504
> > +#define OVM6211_AGC_MAN_SNR_GAIN2	0x3505
> > +/* timing conrol registers */
> > +#define	OVM6211_TVTS_HI			0x380e
> > +#define	OVM6211_TVTS_LO			0x380f
> > +/*Strobe frame span registers*/
> > +#define OVM6211_STROBE_SPAN1		0x3b8d
> > +#define OVM6211_STROBE_SPAN2		0x3b8e
> > +#define OVM6211_STROBE_SPAN3		0x3b8f
> > +/* format control */
> > +#define OVM6211_DATA_MAX_H		0x4300
> > +#define OVM6211_DATA_MIN_H		0x4301
> > +#define OVM6211_CLIP_L			0x4302
> > +#define OVM6211_FORMAT_CTRL3		0x4303
> > +#define OVM6211_FORMAT_CTRL4		0x4304
> > +#define OVM6211_VSYNC_WIDTH_H		0x4311
> > +#define OVM6211_VSYNC_WIDTH_L		0x4312
> > +#define OVM6211_VSYNC_CTRL		0x4313
> > +#define OVM6211_VSYNC_DELAY1		0x4314
> > +#define OVM6211_VSYNC_DELAY2		0x4315
> > +#define OVM6211_VSYNC_DELAY3		0x4316
> > +#define OVM6211_TST_PATTERN_CTRL	0x4320
> > +/* MIPI */
> > +#define OVM6211_MIPI_CTRL00		0x4800
> > +#define OVM6211_MIPI_CTRL01		0x4801
> > +#define OVM6211_MIPI_CTRL02		0x4802
> > +#define OVM6211_MIPI_CTRL03		0x4803
> > +#define OVM6211_MIPI_CTRL04		0x4804
> > +#define OVM6211_MIPI_CTRL05		0x4805
> > +#define OVM6211_MIPI_CTRL06		0x4806
> > +#define OVM6211_MIPI_MAX_FRAME_COUNT_H	0x4810
> > +#define OVM6211_MIPI_MAX_FRAME_COUNT_L	0x4811
> > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_H	0x4812
> > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_L	0x4813
> > +#define OVM6211_MIPI_CTRL14		0x4814
> > +#define OVM6211_MIPI_DT_SPKT		0x4815
> > +#define OVM6211_MIPI_REG_MAX_H		0x4835
> > +#define OVM6211_MIPI_REG_MAX_L		0x4836
> > +#define OVM6211_PCLK_PERIOD		0x4837
> > +#define OVM6211_WKUP_DLY		0x4838
> > +#define OVM6211_DIR_DLY			0x483a
> > +#define OVM6211_MIPI_LP_GPIO		0x483b
> > +#define OVM6211_MIPI_CTRL3C		0x483c
> > +#define OVM6211_T_TA_GO			0x483d
> > +#define OVM6211_T_TA_SURE		0x483e
> > +#define OVM6211_T_TA_GET		0x483f
> > +#define OVM6211_MIPI_CLIP_MAX_H		0x4846
> > +#define OVM6211_MIPI_CLIP_MAX_L		0x4847
> > +#define OVM6211_MIPI_CLIP_MIN_H		0x4848
> > +#define OVM6211_MIPI_CLIP_MIN_L		0x4848
> > +#define OVM6211_REG_INTR_MAN		0x4850
> > +#define OVM6211_REG_TX_WR		0x4851
> > +/* ISP top */
> > +#define OVM6211_ISP_CTRL00		0x5000
> > +#define OVM6211_ISP_CTRL01		0x5001
> > +#define OVM6211_ISP_CTRL02		0x5002
> > +#define OVM6211_ISP_CTRL03		0x5003
> > +#define OVM6211_ISP_CTRL04		0x5004
> > +#define OVM6211_ISP_CTRL05		0x5005
> > +#define OVM6211_ISP_CTRL06		0x5006
> > +#define OVM6211_ISP_CTRL07		0x5007
> > +#define OVM6211_ISP_CTRL08		0x5008
> > +#define OVM6211_ISP_CTRL09		0x5009
> > +/* window control */
> > +#define OVM6211_MAN_XSTART_OFF_H	0x5a00
> > +#define OVM6211_MAN_XSTART_OFF_L	0x5a01
> > +#define OVM6211_MAN_YSTART_OFF_H	0x5a02
> > +#define OVM6211_MAN_YSTART_OFF_L	0x5a03
> > +#define OVM6211_MAN_WIN_WIDTH_H		0x5a04
> > +#define OVM6211_MAN_WIN_WIDTH_L		0x5a05
> > +#define OVM6211_MAN_WIN_HEIGHT_H	0x5a06
> > +#define OVM6211_MAN_WIN_HEIGHT_L	0x5a07
> > +#define OVM6211_WIN_MAN			0x5a08
> > +
> > +#define	OVM6211_LAST_REG		0x5e08
> > +/* end of OVM6211 definitions */
> > +
> > +enum ovm6211_mode_id {
> > +	OVM6211_MODE_Y8_400_200 = 0,
> > +	OVM6211_MODE_Y8_400_400,
> > +	OVM6211_NUM_MODES,
> > +};
> > +
> > +struct ovm6211_pixfmt {
> > +	u32 code;
> > +	u32 colorspace;
> > +};
> > +
> > +static const struct ovm6211_pixfmt ovm6211_formats[] = {
> > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > +};
> > +
> > +enum ovm6211_framerate_ids {
> > +	OVM6211_10_FPS = 0,
> > +	OVM6211_15_FPS,
> > +	OVM6211_30_FPS,
> > +	OVM6211_45_FPS,
> > +	OVM6211_60_FPS,
> > +	OVM6211_NUM_FRAMERATES,
> > +};
> > +
> > +static const int ovm6211_framerates[] = {
> > +	[OVM6211_10_FPS] = 10,
> > +	[OVM6211_15_FPS] = 15,
> > +	[OVM6211_30_FPS] = 30,
> > +	[OVM6211_45_FPS] = 45,
> > +	[OVM6211_60_FPS] = 60,
> > +};
> > +
> > +/* regulator supplies */
> > +static const char * const ovm6211_supply_name[] = {
> > +	"dovdd",
> > +	"avdd",
> > +};
> > +
> > +#define OVM6211_NUM_SUPPLIES ARRAY_SIZE(ovm6211_supply_name)
> 
> I'd suggest to use plain ARRAY_SIZE() instead. This is just an unnecessary
> macro.

This resolves to '2', but i find that both, OVM6211_NUM_SUPPLIES and
ARRAY_SIZE(ovm6211_supply_name) look equally ugly to me. :)

> > +
> > +static const struct regmap_config ovm6211_regmap_config = {
> > +	.reg_bits       = 16,
> > +	.val_bits       = 8,
> > +	.max_register   = OVM6211_LAST_REG,
> > +	.cache_type	= REGCACHE_NONE,
> > +};
> > +
> > +struct reg_value {
> > +	u16 reg_addr;
> > +	u8 val;
> > +	u8 mask;
> > +	u32 delay_ms;
> > +};
> > +
> > +struct ovm6211_mode_info {
> > +	enum ovm6211_mode_id id;
> > +	u32 width;
> > +	u32 height;
> > +	const struct reg_value *reg_data;
> > +	u32 reg_data_size;
> > +	u32 pixel_clock;
> > +};
> > +
> > +struct ovm6211_ctrls {
> > +	struct v4l2_ctrl_handler handler;
> > +	struct {
> > +		struct v4l2_ctrl *auto_exp;
> > +		struct v4l2_ctrl *exposure;
> > +	};
> > +	struct {
> > +		struct v4l2_ctrl *auto_gain;
> > +		struct v4l2_ctrl *gain;
> > +	};
> > +	struct v4l2_ctrl *brightness;
> > +	struct v4l2_ctrl *light_freq;
> > +	struct v4l2_ctrl *saturation;
> > +	struct v4l2_ctrl *contrast;
> > +	struct v4l2_ctrl *hue;
> > +	struct v4l2_ctrl *test_pattern;
> > +	struct v4l2_ctrl *link_freq;
> > +	struct v4l2_ctrl *pixel_clock;
> > +};
> > +
> > +struct ovm6211_dev {
> > +	struct i2c_client *i2c_client;
> > +	struct regmap *regmap;
> > +	struct v4l2_subdev sd;
> > +	struct media_pad pad;
> > +	struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
> > +	struct clk *xclk; /* system clock to OVM6211 */
> > +	u32 xclk_freq;
> > +
> > +	struct regulator_bulk_data supplies[OVM6211_NUM_SUPPLIES];
> > +	struct gpio_desc *reset_gpio;
> > +	struct gpio_desc *pwdn_gpio;
> > +
> > +	struct mutex lock;
> > +
> > +	struct v4l2_mbus_framefmt fmt;
> > +
> > +	const struct ovm6211_mode_info *cur_mode;
> > +	enum ovm6211_framerate_ids cur_fr_id;
> > +	struct v4l2_fract frame_interval;
> > +
> > +	struct ovm6211_ctrls ctrls;
> > +
> > +	u32 exposure;
> > +	bool pending_mode_change;
> > +	bool pending_fi_change;
> > +	bool streaming;
> > +};
> > +
> > +static inline struct ovm6211_dev *to_ovm6211_dev(struct v4l2_subdev *sd)
> > +{
> > +	return container_of(sd, struct ovm6211_dev, sd);
> > +}
> > +
> > +static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
> > +{
> > +	return &container_of(ctrl->handler, struct ovm6211_dev,
> > +			     ctrls.handler)->sd;
> > +}
> > +
> > +static const struct reg_value ovm6211_init_y8_400_400[] = {
> > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0}, {0x3808, 0x01, 0, 0},
> > +	{0x3809, 0x90, 0, 0}, {0x380a, 0x01, 0, 0}, {0x380b, 0x90, 0, 0},
> > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x03, 0, 0},
> > +	{0x380f, 0x6c, 0, 0}, {0x3810, 0x00, 0, 0}, {0x3811, 0x04, 0, 0},
> > +	{0x3812, 0x00, 0, 0}, {0x3813, 0x04, 0, 0}, {0x3814, 0x11, 0, 0},
> > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > +};
> > +
> > +static const struct reg_value ovm6211_init_y8_400_200[] = {
> > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0},
> > +	{0x3808, 0x01, 0, 0},	// W
> > +	{0x3809, 0x90, 0, 0},	// W
> > +	{0x380a, 0x00, 0, 0},	// H
> > +	{0x380b, 0xc8, 0, 0},	// H
> > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x0d, 0, 0},
> > +	{0x380f, 0xb0, 0, 0},
> > +	{0x3810, 0x00, 0, 0},	// W off
> > +	{0x3811, 0x04, 0, 0},	// W off: 4 + (400 - x_width)/2
> > +	{0x3812, 0x00, 0, 0},	// H off
> > +	{0x3813, 0x9a, 0, 0},	// H off: 4 + (400 - y_height)/2
> > +	{0x3814, 0x11, 0, 0},
> > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > +};
> > +
> > +/* power-on sensor init reg table */
> > +static const struct ovm6211_mode_info *ovm6211_mode_init_data;
> > +
> > +static struct ovm6211_mode_info
> > +ovm6211_mode_data[OVM6211_NUM_MODES] = {
> > +	{OVM6211_MODE_Y8_400_200,
> > +	 400, 200,
> > +	 ovm6211_init_y8_400_200,
> > +	 ARRAY_SIZE(ovm6211_init_y8_400_200),
> > +	 400 * 400 * 60 * 2,
> > +	},
> > +	{OVM6211_MODE_Y8_400_400,
> > +	 400, 400,
> > +	 ovm6211_init_y8_400_400,
> > +	 ARRAY_SIZE(ovm6211_init_y8_400_400),
> > +	 400 * 400 * 60 * 2,
> > +	},
> > +};
> > +
> > +static const s64 link_freq_menu_items[] = {
> > +	0,
> > +};
> > +
> > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > +static int ovm6211_get_register(struct v4l2_subdev *sd,
> > +				struct v4l2_dbg_register *reg)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	struct regmap *regmap = sensor->regmap;
> > +	unsigned int val = 0;
> > +	int ret;
> > +
> > +	ret = regmap_read(regmap, reg->reg, &val);
> > +	reg->val = val;
> > +	reg->size = 1;
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_set_register(struct v4l2_subdev *sd,
> > +				const struct v4l2_dbg_register *reg)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	struct regmap *regmap = sensor->regmap;
> > +
> > +	return regmap_write(regmap, reg->reg, reg->val & 0xff);
> > +}
> > +#endif
> > +
> > +static int ovm6211_write_reg(struct ovm6211_dev *sensor, u16 reg, u8 val)
> > +{
> > +	struct i2c_client *client = sensor->i2c_client;
> > +	struct regmap *regmap = sensor->regmap;
> > +	int ret;
> > +
> > +	ret = regmap_write(regmap, reg, val);
> > +	if (ret < 0)
> > +		dev_err(&client->dev, "error writing reg %u\n", reg);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_read_reg(struct ovm6211_dev *sensor, u16 reg, u8 *val)
> > +{
> > +	struct i2c_client *client = sensor->i2c_client;
> > +	struct regmap *regmap = sensor->regmap;
> > +	unsigned int r;
> > +	int ret;
> > +
> > +	ret = regmap_read(regmap, reg, &r);
> > +	if (ret < 0)
> > +		dev_err(&client->dev, "error reading reg %u\n", reg);
> > +	*val = r & 0xff;
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_mod_reg(struct ovm6211_dev *sensor, u16 reg, u8 mask, u8 val)
> > +{
> > +	u8 readval;
> > +	int ret;
> > +
> > +	ret = ovm6211_read_reg(sensor, reg, &readval);
> > +	if (ret)
> > +		return ret;
> > +
> > +	readval &= ~mask;
> > +	val &= mask;
> > +	val |= readval;
> > +
> > +	return ovm6211_write_reg(sensor, reg, val);
> > +}
> > +
> > +static int ovm6211_load_regs(struct ovm6211_dev *sensor,
> > +			     const struct ovm6211_mode_info *mode)
> > +{
> > +	const struct reg_value *regs = mode->reg_data;
> > +	unsigned int i;
> > +	u32 delay_ms;
> > +	u16 reg_addr;
> > +	u8 mask, val;
> > +	int ret = 0;
> > +
> > +	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
> > +		delay_ms = regs->delay_ms;
> > +		reg_addr = regs->reg_addr;
> > +		val = regs->val;
> > +		mask = regs->mask;
> > +		if (mask)
> > +			ret = ovm6211_mod_reg(sensor, reg_addr, mask, val);
> > +		else
> > +			ret = ovm6211_write_reg(sensor, reg_addr, val);
> > +		if (ret)
> > +			break;
> > +
> > +		if (delay_ms) {
> > +			usleep_range(1000 * delay_ms, 1000 * delay_ms + 100);
> > +		}
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static void ovm6211_soft_reset(struct ovm6211_dev *sensor)
> > +{
> > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x01);
> > +	usleep_range(5000, 9000);
> > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x00);
> > +}
> > +
> > +static int ovm6211_set_exposure(struct ovm6211_dev *sensor, u32 exposure)
> > +{
> > +	u32 ce;
> > +	u8 v;
> > +
> > +	ovm6211_read_reg(sensor, OVM6211_TVTS_HI, &v);
> > +	ce = v << 8;
> > +	ovm6211_read_reg(sensor, OVM6211_TVTS_LO, &v);
> > +	ce |= v;
> > +	ce -= 4;
> > +
> > +	if (ce < exposure)
> > +		exposure = ce;
> > +
> > +	ovm6211_mod_reg(sensor, OVM6211_AEC_MANUAL, 1, 1);
> > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO1, (exposure >> 12) & 0x0f);
> > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO2, (exposure >>  4) & 0xff);
> > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO3, (exposure <<  4) & 0xf0);
> > +
> > +	/* set strobe width equal to exposure time */
> > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN1, (exposure >> 16) & 0xff);
> > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN2, (exposure >>  8) & 0xff);
> > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN3, (exposure)       & 0xff);
> > +
> > +	return 0;
> > +}
> > +
> > +static int internal_set_stream(struct ovm6211_dev *sensor, bool on)
> > +{
> > +	u8 hi, lo;
> > +
> > +	if (sensor->pending_fi_change == false)
> > +		goto stream;
> > +
> > +	switch (sensor->cur_fr_id) {
> > +	case OVM6211_10_FPS:
> > +		hi = 0x14;
> > +		lo = 0x88;
> > +		break;
> > +	case OVM6211_15_FPS:
> > +		hi = 0x0d;
> > +		lo = 0xb0;
> > +		break;
> > +	case OVM6211_30_FPS:
> > +		hi = 0x06;
> > +		lo = 0xd8;
> > +		break;
> > +	case OVM6211_45_FPS:
> > +		hi=0x04;
> 
> Spaces around '=', please.

Yeah, this one has slipped through as well.

> > +		lo = 0x90;
> > +		break;
> > +	case OVM6211_60_FPS:
> > +		hi=0x03;
> > +		lo = 0x6c;
> > +		break;
> > +	case OVM6211_NUM_FRAMERATES:
> > +		return -EINVAL;
> > +	}
> > +
> > +	sensor->pending_fi_change = false;
> > +	ovm6211_write_reg(sensor, OVM6211_TVTS_HI, hi);
> > +	ovm6211_write_reg(sensor, OVM6211_TVTS_LO, lo);
> > +stream:
> > +	ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 0);
> > +	if (on) {
> > +		usleep_range(4000, 5000);
> > +		if (sensor->exposure)
> > +			ovm6211_set_exposure(sensor, sensor->exposure);
> > +		ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 1);
> > +		sensor->streaming = true;
> > +	} else {
> > +		sensor->streaming = false;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static struct ovm6211_mode_info *ovm6211_find_mode(int w, int h)
> > +{
> > +	return v4l2_find_nearest_size(ovm6211_mode_data,
> > +				      ARRAY_SIZE(ovm6211_mode_data),
> > +				      width, height, w, h);
> > +}
> > +
> > +static int ovm6211_set_mode(struct ovm6211_dev *sensor)
> > +{
> > +	const struct ovm6211_mode_info *mode = sensor->cur_mode;
> > +
> > +	ovm6211_soft_reset(sensor);
> > +	ovm6211_load_regs(sensor, mode);
> > +
> > +	return 0;
> > +}
> > +
> > +/* --------------- Subdev Operations --------------- */
> > +
> > +static int ovm6211_get_fmt(struct v4l2_subdev *sd,
> > +			   struct v4l2_subdev_state *state,
> > +			   struct v4l2_subdev_format *format)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	struct v4l2_mbus_framefmt *fmt;
> > +
> > +	if (format->pad != 0)
> > +		return -EINVAL;
> > +
> > +	mutex_lock(&sensor->lock);
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > +		format->format = *fmt;
> > +	} else {
> > +		/* these are hardcoded as we don't support anything else */
> > +		format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > +		format->format.field = V4L2_FIELD_NONE;
> > +		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > +		format->format.width = sensor->cur_mode->width;
> > +		format->format.height = sensor->cur_mode->height;
> > +	}
> > +
> > +	mutex_unlock(&sensor->lock);
> > +
> > +	return 0;
> > +}
> > +
> > +u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
> > +{
> > +	u32 s, fmt, fps, ret;
> > +
> > +	/* x * y * [1|2] * y8/y10 * fps */
> > +	s = nm->width * nm->height;
> > +	fmt = 1;
> > +	fps = ovm6211_framerates[sensor->cur_fr_id];
> > +	ret = s * fmt * fps * 2;
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_set_fmt(struct v4l2_subdev *sd,
> > +			   struct v4l2_subdev_state *state,
> > +			   struct v4l2_subdev_format *format)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	struct v4l2_mbus_framefmt *fmt = &format->format;
> > +	struct ovm6211_mode_info *mode;
> > +
> > +	if (format->pad != 0)
> > +		return -EINVAL;
> > +
> > +	if (sensor->streaming)
> > +		return -EBUSY;
> > +
> > +	mutex_lock(&sensor->lock);
> > +
> > +	/* these are hardcoded as we don't support anything else */
> > +	format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > +	format->format.field = V4L2_FIELD_NONE;
> > +	format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > +	mode = ovm6211_find_mode(format->format.width, format->format.height);
> > +	format->format.width = mode->width;
> > +	format->format.height = mode->height;
> > +
> > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > +		*fmt = format->format;
> > +		goto out;
> > +	}
> > +	/* V4L2_SUBDEV_FORMAT_TRY_ACTIVE */
> > +	sensor->cur_mode = mode;
> > +out:
> > +	mutex_unlock(&sensor->lock);
> > +
> > +	return 0;
> > +}
> > +
> > +/*
> > + * Sensor Controls.
> > + */
> > +
> > +static int ovm6211_set_ctrl_exposure(struct ovm6211_dev *sensor, enum
> > +				     v4l2_exposure_auto_type auto_exposure)
> > +{
> > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > +
> > +	if (auto_exposure == V4L2_EXPOSURE_AUTO) {
> > +		sensor->exposure = 0;
> > +	} else {
> > +		sensor->exposure = ctrls->exposure->val;
> > +		ovm6211_set_exposure(sensor, sensor->exposure);
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int ovm6211_set_ctrl_gain(struct ovm6211_dev *sensor, bool auto_gain)
> > +{
> 
> Hmm. Is something missing here?

Nope, just unimplemented.  I might remove it altogether or keep it here as a
placeholder.

> > +	return 0;
> > +}
> > +
> > +static int ovm6211_s_ctrl(struct v4l2_ctrl *ctrl)
> > +{
> > +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	int ret;
> > +
> > +	/* v4l2_ctrl_lock() locks our own mutex */
> > +
> > +	/*
> > +	 * If the device is not powered up by the host driver do
> > +	 * not apply any controls to H/W at this time. Instead
> > +	 * the controls will be restored right after power-up.
> > +	 */
> > +	switch (ctrl->id) {
> > +	case V4L2_CID_GAIN:
> > +		ret = ovm6211_set_ctrl_gain(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_EXPOSURE_AUTO:
> > +		ret = ovm6211_set_ctrl_exposure(sensor, ctrl->val);
> > +		break;
> > +#if 0
> 
> Why?

Some of these are not supported by the sensor, some were not used by the user
space.  I'll just remove them.

> > +	case V4L2_CID_AUTO_WHITE_BALANCE:
> > +		ret = ovm6211_set_ctrl_white_balance(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_HUE:
> > +		ret = ovm6211_set_ctrl_hue(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_CONTRAST:
> > +		ret = ovm6211_set_ctrl_contrast(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_SATURATION:
> > +		ret = ovm6211_set_ctrl_saturation(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_TEST_PATTERN:
> > +		ret = ovm6211_set_ctrl_test_pattern(sensor, ctrl->val);
> > +		break;
> > +	case V4L2_CID_POWER_LINE_FREQUENCY:
> > +		ret = ovm6211_set_ctrl_light_freq(sensor, ctrl->val);
> > +		break;
> > +#endif
> > +	case V4L2_CID_LINK_FREQ:
> > +		return 0;
> > +	case V4L2_CID_PIXEL_RATE:
> > +		return 0;
> > +	default:
> > +		ret = -EINVAL;
> > +		break;
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static const struct v4l2_ctrl_ops ovm6211_ctrl_ops = {
> > +	.s_ctrl = ovm6211_s_ctrl,
> > +};
> > +
> > +static int ovm6211_init_controls(struct ovm6211_dev *sensor)
> > +{
> > +	const struct v4l2_ctrl_ops *ops = &ovm6211_ctrl_ops;
> > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > +	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
> > +	int ret;
> > +
> > +	v4l2_ctrl_handler_init(hdl, 32);
> 
> This number should be more or less the number of controls.

OK.

> > +
> > +	/* we can use our own mutex for the ctrl lock */
> > +	hdl->lock = &sensor->lock;
> > +
> > +	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_EXPOSURE_AUTO,
> > +						 V4L2_EXPOSURE_MANUAL, 0,
> > +						 V4L2_EXPOSURE_AUTO);
> > +	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
> > +					    0, 65535, 1, 0);
> > +	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN,
> > +					0, 1023, 1, 0);
> > +
> > +	v4l2_ctrl_auto_cluster(3, &ctrls->auto_exp, 0, false);
> > +
> > +	ctrls->saturation = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION,
> > +					      0, 255, 1, 64);
> > +	ctrls->hue = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HUE,
> > +				       0, 359, 1, 0);
> > +	ctrls->contrast = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST,
> > +					    0, 255, 1, 0);
> > +	ctrls->light_freq =
> > +		v4l2_ctrl_new_std_menu(hdl, ops,
> > +				       V4L2_CID_POWER_LINE_FREQUENCY,
> > +				       V4L2_CID_POWER_LINE_FREQUENCY_AUTO, 0,
> > +				       V4L2_CID_POWER_LINE_FREQUENCY_50HZ);
> > +	ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
> > +						  0, 0, link_freq_menu_items);
> > +	ctrls->pixel_clock = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
> > +						    1, INT_MAX, 1, 38400000);
> > +
> > +	if (hdl->error) {
> > +		ret = hdl->error;
> > +		goto free_ctrls;
> > +	}
> > +
> > +	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > +	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > +
> > +	sensor->sd.ctrl_handler = hdl;
> > +	return 0;
> > +
> > +free_ctrls:
> > +	v4l2_ctrl_handler_free(hdl);
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_g_frame_interval(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_frame_interval *fi)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +
> > +	mutex_lock(&sensor->lock);
> > +	fi->interval = sensor->frame_interval;
> > +	mutex_unlock(&sensor->lock);
> > +
> > +	return 0;
> > +}
> > +
> > +static int internal_set_frame_interval(struct ovm6211_dev *sensor, struct
> > +				       v4l2_subdev_frame_interval *fi)
> > +{
> > +	u32 fr_rate;
> > +	int i, max, ret = -EINVAL;
> > +
> > +	if (fi->interval.numerator == 0)
> > +		goto out;
> > +
> > +	fr_rate = fi->interval.denominator / fi->interval.numerator;
> > +
> > +	max = ARRAY_SIZE(ovm6211_framerates);
> > +	for (i = 0; i < max; i++) {
> > +		if (ovm6211_framerates[i] == fr_rate)
> > +			break;
> > +	}
> > +
> > +	if (i == max)
> > +		goto out;
> > +
> > +	sensor->cur_fr_id = i;
> > +	sensor->frame_interval = fi->interval;
> > +	ret = 0;
> > +out:
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_s_frame_interval(struct v4l2_subdev *sd,
> > +				    struct v4l2_subdev_frame_interval *fi)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	int ret;
> > +
> > +	mutex_lock(&sensor->lock);
> > +	ret = internal_set_frame_interval(sensor, fi);
> > +	sensor->pending_fi_change = true;
> > +	mutex_unlock(&sensor->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_enum_mbus_code(struct v4l2_subdev *sd,
> > +				  struct v4l2_subdev_state *state,
> > +				  struct v4l2_subdev_mbus_code_enum *code)
> > +{
> > +	if (code->pad != 0)
> > +		return -EINVAL;
> 
> This check can be dropped, the caller has done it already (I assume you
> have a single pad).

OK.

> > +	if (code->index >= ARRAY_SIZE(ovm6211_formats))
> > +		return -EINVAL;
> > +
> > +	code->code = ovm6211_formats[code->index].code;
> > +
> > +	return 0;
> > +}
> > +
> > +static int ovm6211_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +	int ret = 0;
> > +
> > +	mutex_lock(&sensor->lock);
> > +
> > +	if (enable)
> > +		ret = ovm6211_set_mode(sensor);
> > +	internal_set_stream(sensor, enable);
> > +
> > +	mutex_unlock(&sensor->lock);
> > +
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_set_power(struct v4l2_subdev *sd, int on)
> > +{
> > +	return 0;
> > +}
> > +
> > +static const struct v4l2_subdev_core_ops ovm6211_core_ops = {
> > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > +	.g_register = ovm6211_get_register,
> > +	.s_register = ovm6211_set_register,
> > +#endif
> > +	.s_power = ovm6211_set_power,
> > +};
> > +
> > +static const struct v4l2_subdev_video_ops ovm6211_video_ops = {
> > +	.g_frame_interval = ovm6211_g_frame_interval,
> > +	.s_frame_interval = ovm6211_s_frame_interval,
> > +	.s_stream = ovm6211_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops ovm6211_pad_ops = {
> > +	.enum_mbus_code = ovm6211_enum_mbus_code,
> > +	.get_fmt = ovm6211_get_fmt,
> > +	.set_fmt = ovm6211_set_fmt,
> > +};
> > +
> > +static const struct v4l2_subdev_ops ovm6211_subdev_ops = {
> > +	.core = &ovm6211_core_ops,
> > +	.video = &ovm6211_video_ops,
> > +	.pad = &ovm6211_pad_ops,
> > +};
> > +
> > +static int ovm6211_get_regulators(struct ovm6211_dev *sensor)
> > +{
> > +	int i;
> 
> unsigned int, please.

Why?  It isn't like OVM6211_NUM_SUPPLIES will ever be more than single digit
number.

> > +
> > +	for (i = 0; i < OVM6211_NUM_SUPPLIES; i++)
> > +		sensor->supplies[i].supply = ovm6211_supply_name[i];
> > +
> > +	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
> > +				       OVM6211_NUM_SUPPLIES,
> > +				       sensor->supplies);
> > +}
> > +
> > +static int ovm6211_check_chip_id(struct ovm6211_dev *sensor)
> > +{
> > +	struct i2c_client *client = sensor->i2c_client;
> > +	struct regmap *regmap = sensor->regmap;
> > +	unsigned int cid;
> > +	int ret = 0;
> > +
> > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_HIGH, &cid);
> > +	if (ret || cid != 0x67) {
> > +		ret = ENXIO;
> > +		goto err;
> > +	}
> > +
> > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_LOW, &cid);
> > +	if (ret || cid != 0x10) {
> > +		ret = -ENXIO;
> > +		goto err;
> > +	}
> > +
> > +	ret = regmap_read(regmap, OVM6211_SC_REG0C, &cid);
> > +	if (ret)
> > +		goto err;
> > +
> > +	dev_info(&client->dev,"found OVM6211, sub revision: 0x%02X\n", cid);
> > +	return 0;
> > +err:
> > +	dev_err(&client->dev, "failed to detect OVM6211\n");
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_probe(struct i2c_client *client)
> > +{
> > +	struct device *dev = &client->dev;
> > +	struct fwnode_handle *endpoint;
> > +	struct ovm6211_dev *sensor;
> > +	struct v4l2_mbus_framefmt *fmt;
> > +	int ret;
> > +
> > +	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
> > +	if (!sensor)
> > +		return -ENOMEM;
> > +
> > +	sensor->i2c_client = client;
> > +
> > +	/*
> > +	 * default init sequence initialize sensor to
> > +	 * YUV422 UYVY VGA@30fps
> > +	 */
> > +	fmt = &sensor->fmt;
> > +	fmt->code = MEDIA_BUS_FMT_Y8_1X8;
> > +	fmt->colorspace = V4L2_COLORSPACE_RAW;
> > +	fmt->field = V4L2_FIELD_NONE;
> > +	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > +	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> > +	fmt->width = 400;
> > +	fmt->height = 200;
> > +
> > +	sensor->frame_interval.numerator = 1;
> > +	sensor->frame_interval.denominator = ovm6211_framerates[OVM6211_45_FPS];
> > +	sensor->cur_fr_id = OVM6211_45_FPS;
> > +	ovm6211_mode_init_data = &ovm6211_mode_data[OVM6211_MODE_Y8_400_200];
> > +	sensor->cur_mode = ovm6211_mode_init_data;
> > +
> > +	sensor->ep.bus_type = V4L2_MBUS_CSI2_DPHY;
> > +	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
> 
> Over 80, please wrap. Same for other such lines (maybe apart from tables
> etc.).

Ah, i really agree with Linus about this one: https://lkml.org/lkml/2020/5/29/1038

Extensive line breaking is such a pain when reading the code.  Besides, who is
really using 80x25 these days?

> > +	if (!endpoint) {
> > +		dev_err(dev, "endpoint node not found\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ret = v4l2_fwnode_endpoint_parse(endpoint, &sensor->ep);
> > +	fwnode_handle_put(endpoint);
> > +	if (ret) {
> > +		dev_err(dev, "Could not parse endpoint\n");
> > +		return ret;
> > +	}
> > +
> > +	/* get system clock (xclk) */
> > +	sensor->xclk = devm_clk_get(dev, "xvclk");
> 
> This driver seems to be based on register lists. Which xvclk frequency are
> they for?

I am afraid i don't understand this one.

> > +	if (IS_ERR(sensor->xclk)) {
> > +		dev_err(dev, "failed to get xvclk\n");
> > +		return PTR_ERR(sensor->xclk);
> > +	}
> > +
> > +	sensor->xclk_freq = clk_get_rate(sensor->xclk);
> > +	if (sensor->xclk_freq < OVM6211_XVCLK_MIN ||
> > +	    sensor->xclk_freq > OVM6211_XVCLK_MAX) {
> > +		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
> > +			sensor->xclk_freq);
> > +		return -EINVAL;
> > +	}
> > +
> > +	/* request optional power down pin */
> > +	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
> > +						    GPIOD_OUT_HIGH);
> > +	if (IS_ERR(sensor->pwdn_gpio))
> > +		return PTR_ERR(sensor->pwdn_gpio);
> > +
> > +	/* request optional reset pin */
> > +	sensor->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> > +						     GPIOD_OUT_HIGH);
> > +	if (IS_ERR(sensor->reset_gpio))
> > +		return PTR_ERR(sensor->reset_gpio);
> > +
> > +	sensor->regmap = devm_regmap_init_i2c(client, &ovm6211_regmap_config);
> > +	if (IS_ERR(sensor->regmap)) {
> > +		dev_err(dev, "regmap init failed\n");
> > +		return PTR_ERR(sensor->regmap);
> > +	}
> > +
> > +	v4l2_i2c_subdev_init(&sensor->sd, client, &ovm6211_subdev_ops);
> > +
> > +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > +	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
> > +	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > +	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
> > +	if (ret)
> > +		return ret;
> 
> You'll need to call media_entity_cleanup() after this.

Ahem, didn't know that.  Is it documented somewhere so i can read up on this?

> > +
> > +	ret = ovm6211_get_regulators(sensor);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = ovm6211_set_power(&sensor->sd, 1);
> > +	if (ret)
> > +		return ret;
> > +
> > +	mutex_init(&sensor->lock);
> > +
> > +	ret = ovm6211_check_chip_id(sensor);
> > +	if (ret)
> > +		goto entity_cleanup;
> > +
> > +	ret = ovm6211_init_controls(sensor);
> > +	if (ret)
> > +		goto entity_cleanup;
> > +
> > +	ret = v4l2_async_register_subdev_sensor(&sensor->sd);
> > +	if (ret)
> > +		goto free_ctrls;
> > +
> > +	ovm6211_load_regs(sensor, ovm6211_mode_init_data);
> 
> Please add support for runtime PM.
> 
> I'd suggest to take a look at this as well:
> 
> <URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>
> 
> > +
> > +	dev_dbg(dev, "%s() completed\n", __func__);
> 
> Please remove.

OK.

> > +	return 0;
> > +
> > +free_ctrls:
> > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > +entity_cleanup:
> > +	media_entity_cleanup(&sensor->sd.entity);
> > +	mutex_destroy(&sensor->lock);
> > +	return ret;
> > +}
> > +
> > +static int ovm6211_remove(struct i2c_client *client)
> > +{
> > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > +
> > +	v4l2_async_unregister_subdev(&sensor->sd);
> > +	media_entity_cleanup(&sensor->sd.entity);
> > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > +	mutex_destroy(&sensor->lock);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct i2c_device_id ovm6211_id[] = {
> > +	{ "ovm6211", 0 },
> > +	{},
> > +};
> > +MODULE_DEVICE_TABLE(i2c, ovm6211_id);
> > +
> > +static const struct of_device_id ovm6211_dt_ids[] = {
> > +	{ .compatible = "ovti,ovm6211" },
> > +	{ /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, ovm6211_dt_ids);
> > +
> > +static struct i2c_driver ovm6211_i2c_driver = {
> > +	.driver = {
> > +		.name  = "ovm6211",
> > +		.of_match_table	= ovm6211_dt_ids,
> > +	},
> > +	.id_table = ovm6211_id,
> 
> Please remove ovm62211_id table unless you really need it.

OK.

> > +	.probe_new = ovm6211_probe,
> > +	.remove   = ovm6211_remove,
> > +};
> > +
> > +module_i2c_driver(ovm6211_i2c_driver);
> > +
> > +MODULE_AUTHOR("Petko Manolov <petko.manolov@konsulko.com>");
> > +MODULE_DESCRIPTION("OVM6211 MIPI Camera Subdev Driver");
> > +MODULE_LICENSE("GPL");
> 
> -- 
> Kind regards,
> 
> Sakari Ailus

Thanks for the detailed review, Sakari, much appreciated.


cheers,
Petko

Re: [RFC PATCH 1/5] adds ovm6211 driver to staging

[Sakari Ailus]

Hi Petko,

On Tue, Jan 04, 2022 at 05:30:27PM +0200, Petko Manolov wrote:
> On 21-12-07 14:44:14, Sakari Ailus wrote:
> > Hi Petko,
> 
> Hey Sakari.  I've subscribed to linux-media using my company email address.
> Thanks to Google, i found your message in my SPAM folder.  Along with a whole
> bunch of other linux-media, linux-kernel and netdev emails.  Not sure what's
> wrong with the G men these days...

There are many ways to sort e-mail. Maybe they expect you to read that,
too? :-)

> 
> > Thanks for the patchset.
> > 
> > You can squash the other patches into this one (Kconfig and Makefile
> > changes).
> > 
> > Could you also add DT bindings (and CC Rob Herring and the devicetree list) in
> > the future?
> 
> Yup, will do this in parallel with this patch series.
> 
> > On Sat, Dec 04, 2021 at 12:12:43AM +0200, Petko Manolov wrote:
> > 
> > Please add some more description, i.e. not just the subject line.
> 
> Uhm, ok.
> 
> > > Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
> > > ---
> > >  drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++
> > 
> > Why are you targetting the staging tree? We have a number of sensor drivers
> > in the kernel proper already.
> 
> Because it is a new and relatively untested (by the general public) driver.

That doesn't suggest there's a need to target the staging. Bugs are of
course possible but then they're simply fixed.

> 
> > >  1 file changed, 1156 insertions(+)
> > >  create mode 100644 drivers/staging/media/i2c/ovm6211.c
> > > 
> > > diff --git a/drivers/staging/media/i2c/ovm6211.c b/drivers/staging/media/i2c/ovm6211.c
> > > new file mode 100644
> > > index 000000000000..a89c5167a892
> > > --- /dev/null
> > > +++ b/drivers/staging/media/i2c/ovm6211.c
> > > @@ -0,0 +1,1156 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Based on ov5640.c that lives in the same directory.
> > 
> > But we don't have drivers/staging/media/i2c yet?
> > 
> > > + *
> > > + * Copyright (C) 2021 Petko Manolov <petko.manolov@konsulko.com>
> > > + * Copyright (C) 2021 DEKA Research & Development Corp.
> > > + */
> > > +
> > > +#define	DEBUG
> > 
> > Is this still meant to be here?
> 
> Nope, an omission on my part.
> 
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/clk-provider.h>
> > > +#include <linux/clkdev.h>
> > > +#include <linux/ctype.h>
> > 
> > Do you need all the headers here?
> 
> Seems like the answer is yes, devm_clk_get() and clk_get_rate() definitions come
> from these headers.

But linux/ctype.h?

You shouldn't need linux/clkdev.h nor linux/clk-provider.h either.

> 
> > > +#include <linux/delay.h>
> > > +#include <linux/device.h>
> > > +#include <linux/gpio/consumer.h>
> > > +#include <linux/i2c.h>
> > > +#include <linux/init.h>

Please remove.

> > > +#include <linux/module.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/of_device.h>

This one, too.

> > > +#include <linux/regulator/consumer.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/types.h>
> > > +#include <media/v4l2-async.h>
> > > +#include <media/v4l2-ctrls.h>
> > > +#include <media/v4l2-device.h>
> > > +#include <media/v4l2-event.h>
> > > +#include <media/v4l2-fwnode.h>
> > > +#include <media/v4l2-subdev.h>
> > > +
> > > +/* Min/max system clock (xvclk) frequencies */
> > > +#define OVM6211_XVCLK_MIN	 6000000
> > > +#define OVM6211_XVCLK_MAX	27000000
> > > +
> > > +/* begin of OVM6211 definitions */
> > > +/* System Control */
> > > +#define OVM6211_SC_MODE_SELECT		0x0100
> > > +#define OVM6211_SC_SOFTWARE_RESET	0x0103
> > > +#define OVM6211_SC_SCCB_ID1		0x0109
> > > +#define OVM6211_SC_CHIP_ID_HIGH		0x300a
> > > +#define OVM6211_SC_CHIP_ID_LOW		0x300b
> > > +#define OVM6211_SC_REG0C		0x300c
> > > +#define OVM6211_SC_REG10		0x3010
> > > +#define OVM6211_SC_MIPI_PHY		0x3012
> > > +#define OVM6211_SC_MIPI_PHY2		0x3013
> > > +#define OVM6211_SC_MIPI_SC_CTRL0	0x3014
> > > +#define OVM6211_SC_MIPI_SC_CTRL1	0x3015
> > > +#define OVM6211_SC_CLKRST0		0x3016
> > > +#define OVM6211_SC_CLKRST1		0x3017
> > > +#define OVM6211_SC_CLKRST2		0x3018
> > > +#define OVM6211_SC_CLKRST3		0x3019
> > > +#define OVM6211_SC_CLKRST4		0x301a
> > > +#define OVM6211_SC_CLKRST5		0x301b
> > > +#define OVM6211_SC_CLKRST6		0x301c
> > > +#define OVM6211_SC_CLOCK_SEL		0x301e
> > > +#define OVM6211_SC_MISC_CTRL		0x301f
> > > +#define OVM6211_SC_LOW_PWR_CTRL		0x3023
> > > +#define OVM6211_SC_REG27		0x3027
> > > +#define OVM6211_SC_GP_IO_IN1		0x3029
> > > +#define OVM6211_SC_GP_IO_IN2		0x302a
> > > +#define OVM6211_SC_SCCB_ID2		0x302b
> > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD0	0x302c
> > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD1	0x302d
> > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD2	0x302e
> > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD3	0x302f
> > > +#define OVM6211_SC_LP_CTRL0		0x3030
> > > +#define OVM6211_SC_REG37		0x3037
> > > +#define OVM6211_SC_REG3B		0x303b
> > > +/* PLL Control */
> > > +#define OVM6211_PLL_PLL0		0x3080
> > > +#define OVM6211_PLL_PLL1		0x3081
> > > +#define OVM6211_PLL_PLL2		0x3082
> > > +#define OVM6211_PLL_PLL18		0x3098
> > > +#define OVM6211_PLL_PLL19		0x3099
> > > +#define OVM6211_PLL_PLL1A		0x309a
> > > +#define OVM6211_PLL_PLL1B		0x309b
> > > +#define OVM6211_PLL_PLL1C		0x309c
> > > +#define OVM6211_PLL_PLL1D		0x309d
> > > +#define OVM6211_PLL_PLL1E		0x309e
> > > +#define OVM6211_PLL_PLL1F		0x309f
> > > +#define OVM6211_PLL_VT_PIX_CLK_DIV	0x30b0
> > > +#define OVM6211_PLL_VT_SYS_CLK_DIV	0x30b1
> > > +#define OVM6211_PLL_MULTIPLIER		0x30b3
> > > +#define OVM6211_PLL_PLL1_PRE_PLL_DIV	0x30b4
> > > +#define OVM6211_PLL_PLL1_OP_PIX_CLK_DIV	0x30b5
> > > +#define OVM6211_PLL_PLL1_OP_SYS_CLK_DIV	0x30b6
> > > +/* SCCB and group hold */
> > > +#define OVM6211_SB_SRB_CTRL		0x3106
> > > +#define OVM6211_SB_SWITCH		0x31ff
> > > +/* AEC/AGC */
> > > +#define OVM6211_AEC_EXPO1		0x3500
> > > +#define OVM6211_AEC_EXPO2		0x3501
> > > +#define OVM6211_AEC_EXPO3		0x3502
> > > +#define OVM6211_AEC_MANUAL		0x3503
> > > +#define OVM6211_AGC_MAN_SNR_GAIN1	0x3504
> > > +#define OVM6211_AGC_MAN_SNR_GAIN2	0x3505
> > > +/* timing conrol registers */
> > > +#define	OVM6211_TVTS_HI			0x380e
> > > +#define	OVM6211_TVTS_LO			0x380f
> > > +/*Strobe frame span registers*/
> > > +#define OVM6211_STROBE_SPAN1		0x3b8d
> > > +#define OVM6211_STROBE_SPAN2		0x3b8e
> > > +#define OVM6211_STROBE_SPAN3		0x3b8f
> > > +/* format control */
> > > +#define OVM6211_DATA_MAX_H		0x4300
> > > +#define OVM6211_DATA_MIN_H		0x4301
> > > +#define OVM6211_CLIP_L			0x4302
> > > +#define OVM6211_FORMAT_CTRL3		0x4303
> > > +#define OVM6211_FORMAT_CTRL4		0x4304
> > > +#define OVM6211_VSYNC_WIDTH_H		0x4311
> > > +#define OVM6211_VSYNC_WIDTH_L		0x4312
> > > +#define OVM6211_VSYNC_CTRL		0x4313
> > > +#define OVM6211_VSYNC_DELAY1		0x4314
> > > +#define OVM6211_VSYNC_DELAY2		0x4315
> > > +#define OVM6211_VSYNC_DELAY3		0x4316
> > > +#define OVM6211_TST_PATTERN_CTRL	0x4320
> > > +/* MIPI */
> > > +#define OVM6211_MIPI_CTRL00		0x4800
> > > +#define OVM6211_MIPI_CTRL01		0x4801
> > > +#define OVM6211_MIPI_CTRL02		0x4802
> > > +#define OVM6211_MIPI_CTRL03		0x4803
> > > +#define OVM6211_MIPI_CTRL04		0x4804
> > > +#define OVM6211_MIPI_CTRL05		0x4805
> > > +#define OVM6211_MIPI_CTRL06		0x4806
> > > +#define OVM6211_MIPI_MAX_FRAME_COUNT_H	0x4810
> > > +#define OVM6211_MIPI_MAX_FRAME_COUNT_L	0x4811
> > > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_H	0x4812
> > > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_L	0x4813
> > > +#define OVM6211_MIPI_CTRL14		0x4814
> > > +#define OVM6211_MIPI_DT_SPKT		0x4815
> > > +#define OVM6211_MIPI_REG_MAX_H		0x4835
> > > +#define OVM6211_MIPI_REG_MAX_L		0x4836
> > > +#define OVM6211_PCLK_PERIOD		0x4837
> > > +#define OVM6211_WKUP_DLY		0x4838
> > > +#define OVM6211_DIR_DLY			0x483a
> > > +#define OVM6211_MIPI_LP_GPIO		0x483b
> > > +#define OVM6211_MIPI_CTRL3C		0x483c
> > > +#define OVM6211_T_TA_GO			0x483d
> > > +#define OVM6211_T_TA_SURE		0x483e
> > > +#define OVM6211_T_TA_GET		0x483f
> > > +#define OVM6211_MIPI_CLIP_MAX_H		0x4846
> > > +#define OVM6211_MIPI_CLIP_MAX_L		0x4847
> > > +#define OVM6211_MIPI_CLIP_MIN_H		0x4848
> > > +#define OVM6211_MIPI_CLIP_MIN_L		0x4848
> > > +#define OVM6211_REG_INTR_MAN		0x4850
> > > +#define OVM6211_REG_TX_WR		0x4851
> > > +/* ISP top */
> > > +#define OVM6211_ISP_CTRL00		0x5000
> > > +#define OVM6211_ISP_CTRL01		0x5001
> > > +#define OVM6211_ISP_CTRL02		0x5002
> > > +#define OVM6211_ISP_CTRL03		0x5003
> > > +#define OVM6211_ISP_CTRL04		0x5004
> > > +#define OVM6211_ISP_CTRL05		0x5005
> > > +#define OVM6211_ISP_CTRL06		0x5006
> > > +#define OVM6211_ISP_CTRL07		0x5007
> > > +#define OVM6211_ISP_CTRL08		0x5008
> > > +#define OVM6211_ISP_CTRL09		0x5009
> > > +/* window control */
> > > +#define OVM6211_MAN_XSTART_OFF_H	0x5a00
> > > +#define OVM6211_MAN_XSTART_OFF_L	0x5a01
> > > +#define OVM6211_MAN_YSTART_OFF_H	0x5a02
> > > +#define OVM6211_MAN_YSTART_OFF_L	0x5a03
> > > +#define OVM6211_MAN_WIN_WIDTH_H		0x5a04
> > > +#define OVM6211_MAN_WIN_WIDTH_L		0x5a05
> > > +#define OVM6211_MAN_WIN_HEIGHT_H	0x5a06
> > > +#define OVM6211_MAN_WIN_HEIGHT_L	0x5a07
> > > +#define OVM6211_WIN_MAN			0x5a08
> > > +
> > > +#define	OVM6211_LAST_REG		0x5e08
> > > +/* end of OVM6211 definitions */
> > > +
> > > +enum ovm6211_mode_id {
> > > +	OVM6211_MODE_Y8_400_200 = 0,
> > > +	OVM6211_MODE_Y8_400_400,
> > > +	OVM6211_NUM_MODES,
> > > +};
> > > +
> > > +struct ovm6211_pixfmt {
> > > +	u32 code;
> > > +	u32 colorspace;
> > > +};
> > > +
> > > +static const struct ovm6211_pixfmt ovm6211_formats[] = {
> > > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > > +};
> > > +
> > > +enum ovm6211_framerate_ids {
> > > +	OVM6211_10_FPS = 0,
> > > +	OVM6211_15_FPS,
> > > +	OVM6211_30_FPS,
> > > +	OVM6211_45_FPS,
> > > +	OVM6211_60_FPS,
> > > +	OVM6211_NUM_FRAMERATES,
> > > +};
> > > +
> > > +static const int ovm6211_framerates[] = {
> > > +	[OVM6211_10_FPS] = 10,
> > > +	[OVM6211_15_FPS] = 15,
> > > +	[OVM6211_30_FPS] = 30,
> > > +	[OVM6211_45_FPS] = 45,
> > > +	[OVM6211_60_FPS] = 60,
> > > +};
> > > +
> > > +/* regulator supplies */
> > > +static const char * const ovm6211_supply_name[] = {
> > > +	"dovdd",
> > > +	"avdd",
> > > +};
> > > +
> > > +#define OVM6211_NUM_SUPPLIES ARRAY_SIZE(ovm6211_supply_name)
> > 
> > I'd suggest to use plain ARRAY_SIZE() instead. This is just an unnecessary
> > macro.
> 
> This resolves to '2', but i find that both, OVM6211_NUM_SUPPLIES and
> ARRAY_SIZE(ovm6211_supply_name) look equally ugly to me. :)

Plain ARRAY_SIZE() doesn't lose the information what this is about --- it's
easy to see whether the usage is correct or not. With the macro that's not
the case.

> 
> > > +
> > > +static const struct regmap_config ovm6211_regmap_config = {
> > > +	.reg_bits       = 16,
> > > +	.val_bits       = 8,
> > > +	.max_register   = OVM6211_LAST_REG,
> > > +	.cache_type	= REGCACHE_NONE,
> > > +};
> > > +
> > > +struct reg_value {
> > > +	u16 reg_addr;
> > > +	u8 val;
> > > +	u8 mask;
> > > +	u32 delay_ms;
> > > +};
> > > +
> > > +struct ovm6211_mode_info {
> > > +	enum ovm6211_mode_id id;
> > > +	u32 width;
> > > +	u32 height;
> > > +	const struct reg_value *reg_data;
> > > +	u32 reg_data_size;
> > > +	u32 pixel_clock;
> > > +};
> > > +
> > > +struct ovm6211_ctrls {
> > > +	struct v4l2_ctrl_handler handler;
> > > +	struct {
> > > +		struct v4l2_ctrl *auto_exp;
> > > +		struct v4l2_ctrl *exposure;
> > > +	};
> > > +	struct {
> > > +		struct v4l2_ctrl *auto_gain;
> > > +		struct v4l2_ctrl *gain;
> > > +	};
> > > +	struct v4l2_ctrl *brightness;
> > > +	struct v4l2_ctrl *light_freq;
> > > +	struct v4l2_ctrl *saturation;
> > > +	struct v4l2_ctrl *contrast;
> > > +	struct v4l2_ctrl *hue;
> > > +	struct v4l2_ctrl *test_pattern;
> > > +	struct v4l2_ctrl *link_freq;
> > > +	struct v4l2_ctrl *pixel_clock;

Please only keep references to the ones you need. pixel_clock, for
instance, remains unused.

> > > +};
> > > +
> > > +struct ovm6211_dev {
> > > +	struct i2c_client *i2c_client;
> > > +	struct regmap *regmap;
> > > +	struct v4l2_subdev sd;
> > > +	struct media_pad pad;
> > > +	struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
> > > +	struct clk *xclk; /* system clock to OVM6211 */
> > > +	u32 xclk_freq;
> > > +
> > > +	struct regulator_bulk_data supplies[OVM6211_NUM_SUPPLIES];
> > > +	struct gpio_desc *reset_gpio;
> > > +	struct gpio_desc *pwdn_gpio;
> > > +
> > > +	struct mutex lock;
> > > +
> > > +	struct v4l2_mbus_framefmt fmt;
> > > +
> > > +	const struct ovm6211_mode_info *cur_mode;
> > > +	enum ovm6211_framerate_ids cur_fr_id;
> > > +	struct v4l2_fract frame_interval;
> > > +
> > > +	struct ovm6211_ctrls ctrls;
> > > +
> > > +	u32 exposure;
> > > +	bool pending_mode_change;
> > > +	bool pending_fi_change;
> > > +	bool streaming;
> > > +};
> > > +
> > > +static inline struct ovm6211_dev *to_ovm6211_dev(struct v4l2_subdev *sd)
> > > +{
> > > +	return container_of(sd, struct ovm6211_dev, sd);
> > > +}
> > > +
> > > +static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
> > > +{
> > > +	return &container_of(ctrl->handler, struct ovm6211_dev,
> > > +			     ctrls.handler)->sd;
> > > +}
> > > +
> > > +static const struct reg_value ovm6211_init_y8_400_400[] = {
> > > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0}, {0x3808, 0x01, 0, 0},
> > > +	{0x3809, 0x90, 0, 0}, {0x380a, 0x01, 0, 0}, {0x380b, 0x90, 0, 0},
> > > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x03, 0, 0},
> > > +	{0x380f, 0x6c, 0, 0}, {0x3810, 0x00, 0, 0}, {0x3811, 0x04, 0, 0},
> > > +	{0x3812, 0x00, 0, 0}, {0x3813, 0x04, 0, 0}, {0x3814, 0x11, 0, 0},
> > > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > > +};
> > > +
> > > +static const struct reg_value ovm6211_init_y8_400_200[] = {
> > > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0},
> > > +	{0x3808, 0x01, 0, 0},	// W
> > > +	{0x3809, 0x90, 0, 0},	// W
> > > +	{0x380a, 0x00, 0, 0},	// H
> > > +	{0x380b, 0xc8, 0, 0},	// H

/* C comments, please */

> > > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x0d, 0, 0},
> > > +	{0x380f, 0xb0, 0, 0},
> > > +	{0x3810, 0x00, 0, 0},	// W off
> > > +	{0x3811, 0x04, 0, 0},	// W off: 4 + (400 - x_width)/2
> > > +	{0x3812, 0x00, 0, 0},	// H off
> > > +	{0x3813, 0x9a, 0, 0},	// H off: 4 + (400 - y_height)/2
> > > +	{0x3814, 0x11, 0, 0},
> > > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > > +};
> > > +
> > > +/* power-on sensor init reg table */
> > > +static const struct ovm6211_mode_info *ovm6211_mode_init_data;

Used in probe only. Please remove.

> > > +
> > > +static struct ovm6211_mode_info
> > > +ovm6211_mode_data[OVM6211_NUM_MODES] = {
> > > +	{OVM6211_MODE_Y8_400_200,
> > > +	 400, 200,
> > > +	 ovm6211_init_y8_400_200,
> > > +	 ARRAY_SIZE(ovm6211_init_y8_400_200),
> > > +	 400 * 400 * 60 * 2,
> > > +	},
> > > +	{OVM6211_MODE_Y8_400_400,
> > > +	 400, 400,
> > > +	 ovm6211_init_y8_400_400,
> > > +	 ARRAY_SIZE(ovm6211_init_y8_400_400),
> > > +	 400 * 400 * 60 * 2,
> > > +	},
> > > +};
> > > +
> > > +static const s64 link_freq_menu_items[] = {
> > > +	0,
> > > +};
> > > +
> > > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > > +static int ovm6211_get_register(struct v4l2_subdev *sd,
> > > +				struct v4l2_dbg_register *reg)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	struct regmap *regmap = sensor->regmap;
> > > +	unsigned int val = 0;
> > > +	int ret;
> > > +
> > > +	ret = regmap_read(regmap, reg->reg, &val);
> > > +	reg->val = val;
> > > +	reg->size = 1;
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_set_register(struct v4l2_subdev *sd,
> > > +				const struct v4l2_dbg_register *reg)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	struct regmap *regmap = sensor->regmap;
> > > +
> > > +	return regmap_write(regmap, reg->reg, reg->val & 0xff);
> > > +}
> > > +#endif
> > > +
> > > +static int ovm6211_write_reg(struct ovm6211_dev *sensor, u16 reg, u8 val)
> > > +{
> > > +	struct i2c_client *client = sensor->i2c_client;
> > > +	struct regmap *regmap = sensor->regmap;
> > > +	int ret;
> > > +
> > > +	ret = regmap_write(regmap, reg, val);
> > > +	if (ret < 0)
> > > +		dev_err(&client->dev, "error writing reg %u\n", reg);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_read_reg(struct ovm6211_dev *sensor, u16 reg, u8 *val)
> > > +{
> > > +	struct i2c_client *client = sensor->i2c_client;
> > > +	struct regmap *regmap = sensor->regmap;
> > > +	unsigned int r;
> > > +	int ret;
> > > +
> > > +	ret = regmap_read(regmap, reg, &r);
> > > +	if (ret < 0)
> > > +		dev_err(&client->dev, "error reading reg %u\n", reg);
> > > +	*val = r & 0xff;
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_mod_reg(struct ovm6211_dev *sensor, u16 reg, u8 mask, u8 val)
> > > +{
> > > +	u8 readval;
> > > +	int ret;
> > > +
> > > +	ret = ovm6211_read_reg(sensor, reg, &readval);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	readval &= ~mask;
> > > +	val &= mask;
> > > +	val |= readval;
> > > +
> > > +	return ovm6211_write_reg(sensor, reg, val);
> > > +}
> > > +
> > > +static int ovm6211_load_regs(struct ovm6211_dev *sensor,
> > > +			     const struct ovm6211_mode_info *mode)
> > > +{
> > > +	const struct reg_value *regs = mode->reg_data;
> > > +	unsigned int i;
> > > +	u32 delay_ms;
> > > +	u16 reg_addr;
> > > +	u8 mask, val;
> > > +	int ret = 0;
> > > +
> > > +	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
> > > +		delay_ms = regs->delay_ms;
> > > +		reg_addr = regs->reg_addr;
> > > +		val = regs->val;
> > > +		mask = regs->mask;
> > > +		if (mask)
> > > +			ret = ovm6211_mod_reg(sensor, reg_addr, mask, val);
> > > +		else
> > > +			ret = ovm6211_write_reg(sensor, reg_addr, val);
> > > +		if (ret)
> > > +			break;
> > > +
> > > +		if (delay_ms) {
> > > +			usleep_range(1000 * delay_ms, 1000 * delay_ms + 100);
> > > +		}
> > > +	}
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static void ovm6211_soft_reset(struct ovm6211_dev *sensor)
> > > +{
> > > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x01);
> > > +	usleep_range(5000, 9000);
> > > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x00);
> > > +}
> > > +
> > > +static int ovm6211_set_exposure(struct ovm6211_dev *sensor, u32 exposure)
> > > +{
> > > +	u32 ce;
> > > +	u8 v;
> > > +
> > > +	ovm6211_read_reg(sensor, OVM6211_TVTS_HI, &v);
> > > +	ce = v << 8;
> > > +	ovm6211_read_reg(sensor, OVM6211_TVTS_LO, &v);
> > > +	ce |= v;
> > > +	ce -= 4;
> > > +
> > > +	if (ce < exposure)
> > > +		exposure = ce;
> > > +
> > > +	ovm6211_mod_reg(sensor, OVM6211_AEC_MANUAL, 1, 1);
> > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO1, (exposure >> 12) & 0x0f);
> > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO2, (exposure >>  4) & 0xff);
> > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO3, (exposure <<  4) & 0xf0);
> > > +
> > > +	/* set strobe width equal to exposure time */
> > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN1, (exposure >> 16) & 0xff);
> > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN2, (exposure >>  8) & 0xff);
> > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN3, (exposure)       & 0xff);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int internal_set_stream(struct ovm6211_dev *sensor, bool on)
> > > +{
> > > +	u8 hi, lo;
> > > +
> > > +	if (sensor->pending_fi_change == false)
> > > +		goto stream;
> > > +
> > > +	switch (sensor->cur_fr_id) {
> > > +	case OVM6211_10_FPS:
> > > +		hi = 0x14;
> > > +		lo = 0x88;
> > > +		break;
> > > +	case OVM6211_15_FPS:
> > > +		hi = 0x0d;
> > > +		lo = 0xb0;
> > > +		break;
> > > +	case OVM6211_30_FPS:
> > > +		hi = 0x06;
> > > +		lo = 0xd8;
> > > +		break;
> > > +	case OVM6211_45_FPS:
> > > +		hi=0x04;
> > 
> > Spaces around '=', please.
> 
> Yeah, this one has slipped through as well.
> 
> > > +		lo = 0x90;
> > > +		break;
> > > +	case OVM6211_60_FPS:
> > > +		hi=0x03;
> > > +		lo = 0x6c;
> > > +		break;
> > > +	case OVM6211_NUM_FRAMERATES:
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	sensor->pending_fi_change = false;
> > > +	ovm6211_write_reg(sensor, OVM6211_TVTS_HI, hi);
> > > +	ovm6211_write_reg(sensor, OVM6211_TVTS_LO, lo);
> > > +stream:
> > > +	ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 0);
> > > +	if (on) {
> > > +		usleep_range(4000, 5000);
> > > +		if (sensor->exposure)
> > > +			ovm6211_set_exposure(sensor, sensor->exposure);
> > > +		ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 1);
> > > +		sensor->streaming = true;
> > > +	} else {
> > > +		sensor->streaming = false;
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static struct ovm6211_mode_info *ovm6211_find_mode(int w, int h)

This function only has a single user. Please call v4l2_find_nearest_size()
directly instead.

> > > +{
> > > +	return v4l2_find_nearest_size(ovm6211_mode_data,
> > > +				      ARRAY_SIZE(ovm6211_mode_data),
> > > +				      width, height, w, h);
> > > +}
> > > +
> > > +static int ovm6211_set_mode(struct ovm6211_dev *sensor)
> > > +{
> > > +	const struct ovm6211_mode_info *mode = sensor->cur_mode;
> > > +
> > > +	ovm6211_soft_reset(sensor);
> > > +	ovm6211_load_regs(sensor, mode);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +/* --------------- Subdev Operations --------------- */
> > > +
> > > +static int ovm6211_get_fmt(struct v4l2_subdev *sd,
> > > +			   struct v4l2_subdev_state *state,
> > > +			   struct v4l2_subdev_format *format)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	struct v4l2_mbus_framefmt *fmt;
> > > +
> > > +	if (format->pad != 0)
> > > +		return -EINVAL;
> > > +
> > > +	mutex_lock(&sensor->lock);
> > > +
> > > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > > +		format->format = *fmt;
> > > +	} else {
> > > +		/* these are hardcoded as we don't support anything else */
> > > +		format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > > +		format->format.field = V4L2_FIELD_NONE;
> > > +		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > > +		format->format.width = sensor->cur_mode->width;
> > > +		format->format.height = sensor->cur_mode->height;
> > > +	}
> > > +
> > > +	mutex_unlock(&sensor->lock);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
> > > +{
> > > +	u32 s, fmt, fps, ret;
> > > +
> > > +	/* x * y * [1|2] * y8/y10 * fps */
> > > +	s = nm->width * nm->height;
> > > +	fmt = 1;
> > > +	fps = ovm6211_framerates[sensor->cur_fr_id];
> > > +	ret = s * fmt * fps * 2;
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_set_fmt(struct v4l2_subdev *sd,
> > > +			   struct v4l2_subdev_state *state,
> > > +			   struct v4l2_subdev_format *format)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	struct v4l2_mbus_framefmt *fmt = &format->format;
> > > +	struct ovm6211_mode_info *mode;
> > > +
> > > +	if (format->pad != 0)

The caller will have checked this already (assuming there's just a single
pad). Same in get_fmt.

> > > +		return -EINVAL;
> > > +
> > > +	if (sensor->streaming)

This check should be done when the mutex is taken.

> > > +		return -EBUSY;
> > > +
> > > +	mutex_lock(&sensor->lock);
> > > +
> > > +	/* these are hardcoded as we don't support anything else */
> > > +	format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > > +	format->format.field = V4L2_FIELD_NONE;
> > > +	format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > > +	mode = ovm6211_find_mode(format->format.width, format->format.height);
> > > +	format->format.width = mode->width;
> > > +	format->format.height = mode->height;
> > > +
> > > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > > +		*fmt = format->format;
> > > +		goto out;
> > > +	}
> > > +	/* V4L2_SUBDEV_FORMAT_TRY_ACTIVE */
> > > +	sensor->cur_mode = mode;
> > > +out:
> > > +	mutex_unlock(&sensor->lock);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +/*
> > > + * Sensor Controls.
> > > + */
> > > +
> > > +static int ovm6211_set_ctrl_exposure(struct ovm6211_dev *sensor, enum
> > > +				     v4l2_exposure_auto_type auto_exposure)
> > > +{
> > > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > > +
> > > +	if (auto_exposure == V4L2_EXPOSURE_AUTO) {
> > > +		sensor->exposure = 0;
> > > +	} else {
> > > +		sensor->exposure = ctrls->exposure->val;
> > > +		ovm6211_set_exposure(sensor, sensor->exposure);
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ovm6211_set_ctrl_gain(struct ovm6211_dev *sensor, bool auto_gain)
> > > +{
> > 
> > Hmm. Is something missing here?
> 
> Nope, just unimplemented.  I might remove it altogether or keep it here as a
> placeholder.

Please either remove or add the implementation. This should be more or less
trivial to implement though.

> 
> > > +	return 0;
> > > +}
> > > +
> > > +static int ovm6211_s_ctrl(struct v4l2_ctrl *ctrl)
> > > +{
> > > +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	int ret;
> > > +
> > > +	/* v4l2_ctrl_lock() locks our own mutex */
> > > +
> > > +	/*
> > > +	 * If the device is not powered up by the host driver do
> > > +	 * not apply any controls to H/W at this time. Instead
> > > +	 * the controls will be restored right after power-up.
> > > +	 */
> > > +	switch (ctrl->id) {
> > > +	case V4L2_CID_GAIN:
> > > +		ret = ovm6211_set_ctrl_gain(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_EXPOSURE_AUTO:
> > > +		ret = ovm6211_set_ctrl_exposure(sensor, ctrl->val);
> > > +		break;
> > > +#if 0
> > 
> > Why?
> 
> Some of these are not supported by the sensor, some were not used by the user
> space.  I'll just remove them.

Sounds good.

> 
> > > +	case V4L2_CID_AUTO_WHITE_BALANCE:
> > > +		ret = ovm6211_set_ctrl_white_balance(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_HUE:
> > > +		ret = ovm6211_set_ctrl_hue(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_CONTRAST:
> > > +		ret = ovm6211_set_ctrl_contrast(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_SATURATION:
> > > +		ret = ovm6211_set_ctrl_saturation(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_TEST_PATTERN:
> > > +		ret = ovm6211_set_ctrl_test_pattern(sensor, ctrl->val);
> > > +		break;
> > > +	case V4L2_CID_POWER_LINE_FREQUENCY:
> > > +		ret = ovm6211_set_ctrl_light_freq(sensor, ctrl->val);
> > > +		break;
> > > +#endif
> > > +	case V4L2_CID_LINK_FREQ:
> > > +		return 0;
> > > +	case V4L2_CID_PIXEL_RATE:
> > > +		return 0;
> > > +	default:
> > > +		ret = -EINVAL;
> > > +		break;
> > > +	}
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static const struct v4l2_ctrl_ops ovm6211_ctrl_ops = {
> > > +	.s_ctrl = ovm6211_s_ctrl,
> > > +};
> > > +
> > > +static int ovm6211_init_controls(struct ovm6211_dev *sensor)
> > > +{
> > > +	const struct v4l2_ctrl_ops *ops = &ovm6211_ctrl_ops;
> > > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > > +	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
> > > +	int ret;
> > > +
> > > +	v4l2_ctrl_handler_init(hdl, 32);
> > 
> > This number should be more or less the number of controls.
> 
> OK.
> 
> > > +
> > > +	/* we can use our own mutex for the ctrl lock */
> > > +	hdl->lock = &sensor->lock;
> > > +
> > > +	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_EXPOSURE_AUTO,
> > > +						 V4L2_EXPOSURE_MANUAL, 0,
> > > +						 V4L2_EXPOSURE_AUTO);
> > > +	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
> > > +					    0, 65535, 1, 0);
> > > +	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN,
> > > +					0, 1023, 1, 0);
> > > +
> > > +	v4l2_ctrl_auto_cluster(3, &ctrls->auto_exp, 0, false);
> > > +
> > > +	ctrls->saturation = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION,
> > > +					      0, 255, 1, 64);
> > > +	ctrls->hue = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HUE,
> > > +				       0, 359, 1, 0);
> > > +	ctrls->contrast = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST,
> > > +					    0, 255, 1, 0);
> > > +	ctrls->light_freq =
> > > +		v4l2_ctrl_new_std_menu(hdl, ops,
> > > +				       V4L2_CID_POWER_LINE_FREQUENCY,
> > > +				       V4L2_CID_POWER_LINE_FREQUENCY_AUTO, 0,
> > > +				       V4L2_CID_POWER_LINE_FREQUENCY_50HZ);
> > > +	ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
> > > +						  0, 0, link_freq_menu_items);
> > > +	ctrls->pixel_clock = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
> > > +						    1, INT_MAX, 1, 38400000);
> > > +
> > > +	if (hdl->error) {
> > > +		ret = hdl->error;
> > > +		goto free_ctrls;
> > > +	}
> > > +
> > > +	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > > +	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > > +
> > > +	sensor->sd.ctrl_handler = hdl;
> > > +	return 0;
> > > +
> > > +free_ctrls:
> > > +	v4l2_ctrl_handler_free(hdl);
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_g_frame_interval(struct v4l2_subdev *sd,
> > > +				    struct v4l2_subdev_frame_interval *fi)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +
> > > +	mutex_lock(&sensor->lock);
> > > +	fi->interval = sensor->frame_interval;
> > > +	mutex_unlock(&sensor->lock);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int internal_set_frame_interval(struct ovm6211_dev *sensor, struct
> > > +				       v4l2_subdev_frame_interval *fi)
> > > +{
> > > +	u32 fr_rate;
> > > +	int i, max, ret = -EINVAL;
> > > +
> > > +	if (fi->interval.numerator == 0)
> > > +		goto out;
> > > +
> > > +	fr_rate = fi->interval.denominator / fi->interval.numerator;
> > > +
> > > +	max = ARRAY_SIZE(ovm6211_framerates);
> > > +	for (i = 0; i < max; i++) {
> > > +		if (ovm6211_framerates[i] == fr_rate)
> > > +			break;
> > > +	}
> > > +
> > > +	if (i == max)
> > > +		goto out;
> > > +
> > > +	sensor->cur_fr_id = i;
> > > +	sensor->frame_interval = fi->interval;
> > > +	ret = 0;
> > > +out:
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_s_frame_interval(struct v4l2_subdev *sd,
> > > +				    struct v4l2_subdev_frame_interval *fi)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	int ret;
> > > +
> > > +	mutex_lock(&sensor->lock);
> > > +	ret = internal_set_frame_interval(sensor, fi);
> > > +	sensor->pending_fi_change = true;
> > > +	mutex_unlock(&sensor->lock);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_enum_mbus_code(struct v4l2_subdev *sd,
> > > +				  struct v4l2_subdev_state *state,
> > > +				  struct v4l2_subdev_mbus_code_enum *code)
> > > +{
> > > +	if (code->pad != 0)
> > > +		return -EINVAL;
> > 
> > This check can be dropped, the caller has done it already (I assume you
> > have a single pad).
> 
> OK.
> 
> > > +	if (code->index >= ARRAY_SIZE(ovm6211_formats))
> > > +		return -EINVAL;
> > > +
> > > +	code->code = ovm6211_formats[code->index].code;
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int ovm6211_s_stream(struct v4l2_subdev *sd, int enable)
> > > +{
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +	int ret = 0;
> > > +
> > > +	mutex_lock(&sensor->lock);
> > > +
> > > +	if (enable)
> > > +		ret = ovm6211_set_mode(sensor);
> > > +	internal_set_stream(sensor, enable);
> > > +
> > > +	mutex_unlock(&sensor->lock);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_set_power(struct v4l2_subdev *sd, int on)
> > > +{
> > > +	return 0;
> > > +}
> > > +
> > > +static const struct v4l2_subdev_core_ops ovm6211_core_ops = {
> > > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > > +	.g_register = ovm6211_get_register,
> > > +	.s_register = ovm6211_set_register,
> > > +#endif
> > > +	.s_power = ovm6211_set_power,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_video_ops ovm6211_video_ops = {
> > > +	.g_frame_interval = ovm6211_g_frame_interval,
> > > +	.s_frame_interval = ovm6211_s_frame_interval,
> > > +	.s_stream = ovm6211_s_stream,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_pad_ops ovm6211_pad_ops = {
> > > +	.enum_mbus_code = ovm6211_enum_mbus_code,
> > > +	.get_fmt = ovm6211_get_fmt,
> > > +	.set_fmt = ovm6211_set_fmt,
> > > +};
> > > +
> > > +static const struct v4l2_subdev_ops ovm6211_subdev_ops = {
> > > +	.core = &ovm6211_core_ops,
> > > +	.video = &ovm6211_video_ops,
> > > +	.pad = &ovm6211_pad_ops,
> > > +};
> > > +
> > > +static int ovm6211_get_regulators(struct ovm6211_dev *sensor)
> > > +{
> > > +	int i;
> > 
> > unsigned int, please.
> 
> Why?  It isn't like OVM6211_NUM_SUPPLIES will ever be more than single digit
> number.

It's better to compare two unsigned values rather than one signed and
another unsigned.

> 
> > > +
> > > +	for (i = 0; i < OVM6211_NUM_SUPPLIES; i++)
> > > +		sensor->supplies[i].supply = ovm6211_supply_name[i];
> > > +
> > > +	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
> > > +				       OVM6211_NUM_SUPPLIES,
> > > +				       sensor->supplies);
> > > +}
> > > +
> > > +static int ovm6211_check_chip_id(struct ovm6211_dev *sensor)
> > > +{
> > > +	struct i2c_client *client = sensor->i2c_client;
> > > +	struct regmap *regmap = sensor->regmap;
> > > +	unsigned int cid;
> > > +	int ret = 0;
> > > +
> > > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_HIGH, &cid);
> > > +	if (ret || cid != 0x67) {
> > > +		ret = ENXIO;
> > > +		goto err;
> > > +	}
> > > +
> > > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_LOW, &cid);
> > > +	if (ret || cid != 0x10) {
> > > +		ret = -ENXIO;
> > > +		goto err;
> > > +	}
> > > +
> > > +	ret = regmap_read(regmap, OVM6211_SC_REG0C, &cid);
> > > +	if (ret)
> > > +		goto err;
> > > +
> > > +	dev_info(&client->dev,"found OVM6211, sub revision: 0x%02X\n", cid);
> > > +	return 0;
> > > +err:
> > > +	dev_err(&client->dev, "failed to detect OVM6211\n");
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_probe(struct i2c_client *client)
> > > +{
> > > +	struct device *dev = &client->dev;
> > > +	struct fwnode_handle *endpoint;
> > > +	struct ovm6211_dev *sensor;
> > > +	struct v4l2_mbus_framefmt *fmt;
> > > +	int ret;
> > > +
> > > +	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
> > > +	if (!sensor)
> > > +		return -ENOMEM;
> > > +
> > > +	sensor->i2c_client = client;
> > > +
> > > +	/*
> > > +	 * default init sequence initialize sensor to
> > > +	 * YUV422 UYVY VGA@30fps
> > > +	 */
> > > +	fmt = &sensor->fmt;
> > > +	fmt->code = MEDIA_BUS_FMT_Y8_1X8;
> > > +	fmt->colorspace = V4L2_COLORSPACE_RAW;
> > > +	fmt->field = V4L2_FIELD_NONE;
> > > +	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > +	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> > > +	fmt->width = 400;
> > > +	fmt->height = 200;
> > > +
> > > +	sensor->frame_interval.numerator = 1;
> > > +	sensor->frame_interval.denominator = ovm6211_framerates[OVM6211_45_FPS];
> > > +	sensor->cur_fr_id = OVM6211_45_FPS;
> > > +	ovm6211_mode_init_data = &ovm6211_mode_data[OVM6211_MODE_Y8_400_200];
> > > +	sensor->cur_mode = ovm6211_mode_init_data;
> > > +
> > > +	sensor->ep.bus_type = V4L2_MBUS_CSI2_DPHY;
> > > +	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
> > 
> > Over 80, please wrap. Same for other such lines (maybe apart from tables
> > etc.).
> 
> Ah, i really agree with Linus about this one: https://lkml.org/lkml/2020/5/29/1038
> 
> Extensive line breaking is such a pain when reading the code.  Besides, who is
> really using 80x25 these days?

Still the coding style encourages lines no longer than 80 albeit in some
cases other factors may be more important than that.

> 
> > > +	if (!endpoint) {
> > > +		dev_err(dev, "endpoint node not found\n");
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	ret = v4l2_fwnode_endpoint_parse(endpoint, &sensor->ep);
> > > +	fwnode_handle_put(endpoint);
> > > +	if (ret) {
> > > +		dev_err(dev, "Could not parse endpoint\n");
> > > +		return ret;
> > > +	}
> > > +
> > > +	/* get system clock (xclk) */
> > > +	sensor->xclk = devm_clk_get(dev, "xvclk");
> > 
> > This driver seems to be based on register lists. Which xvclk frequency are
> > they for?
> 
> I am afraid i don't understand this one.

The sensor has a PLL for generating higher clock frequencies than the
external clock input signal. The PLL has limits within it may operate, and
its configuration set in registers as well as the external clock frequency
need to be consistent in such a way these limits are not breached.

Also see
<URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>.

> 
> > > +	if (IS_ERR(sensor->xclk)) {
> > > +		dev_err(dev, "failed to get xvclk\n");
> > > +		return PTR_ERR(sensor->xclk);
> > > +	}
> > > +
> > > +	sensor->xclk_freq = clk_get_rate(sensor->xclk);
> > > +	if (sensor->xclk_freq < OVM6211_XVCLK_MIN ||
> > > +	    sensor->xclk_freq > OVM6211_XVCLK_MAX) {
> > > +		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
> > > +			sensor->xclk_freq);
> > > +		return -EINVAL;
> > > +	}
> > > +
> > > +	/* request optional power down pin */
> > > +	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
> > > +						    GPIOD_OUT_HIGH);
> > > +	if (IS_ERR(sensor->pwdn_gpio))
> > > +		return PTR_ERR(sensor->pwdn_gpio);
> > > +
> > > +	/* request optional reset pin */
> > > +	sensor->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> > > +						     GPIOD_OUT_HIGH);
> > > +	if (IS_ERR(sensor->reset_gpio))
> > > +		return PTR_ERR(sensor->reset_gpio);
> > > +
> > > +	sensor->regmap = devm_regmap_init_i2c(client, &ovm6211_regmap_config);
> > > +	if (IS_ERR(sensor->regmap)) {
> > > +		dev_err(dev, "regmap init failed\n");
> > > +		return PTR_ERR(sensor->regmap);
> > > +	}
> > > +
> > > +	v4l2_i2c_subdev_init(&sensor->sd, client, &ovm6211_subdev_ops);
> > > +
> > > +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > +	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > +	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > +	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
> > > +	if (ret)
> > > +		return ret;
> > 
> > You'll need to call media_entity_cleanup() after this.
> 
> Ahem, didn't know that.  Is it documented somewhere so i can read up on this?

See include/media/media-entity.h .

The function currently does nothing and we might remove it in the future.
But for now, please do use it.

> 
> > > +
> > > +	ret = ovm6211_get_regulators(sensor);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	ret = ovm6211_set_power(&sensor->sd, 1);
> > > +	if (ret)
> > > +		return ret;
> > > +
> > > +	mutex_init(&sensor->lock);
> > > +
> > > +	ret = ovm6211_check_chip_id(sensor);
> > > +	if (ret)
> > > +		goto entity_cleanup;
> > > +
> > > +	ret = ovm6211_init_controls(sensor);
> > > +	if (ret)
> > > +		goto entity_cleanup;
> > > +
> > > +	ret = v4l2_async_register_subdev_sensor(&sensor->sd);

Note that the sensor could be already be used by user space at this point.
All initialisation needs thus to precede registering the async subdev.

> > > +	if (ret)
> > > +		goto free_ctrls;
> > > +
> > > +	ovm6211_load_regs(sensor, ovm6211_mode_init_data);
> > 
> > Please add support for runtime PM.
> > 
> > I'd suggest to take a look at this as well:
> > 
> > <URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>
> > 
> > > +
> > > +	dev_dbg(dev, "%s() completed\n", __func__);
> > 
> > Please remove.
> 
> OK.
> 
> > > +	return 0;
> > > +
> > > +free_ctrls:
> > > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > > +entity_cleanup:
> > > +	media_entity_cleanup(&sensor->sd.entity);
> > > +	mutex_destroy(&sensor->lock);
> > > +	return ret;
> > > +}
> > > +
> > > +static int ovm6211_remove(struct i2c_client *client)
> > > +{
> > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > +
> > > +	v4l2_async_unregister_subdev(&sensor->sd);
> > > +	media_entity_cleanup(&sensor->sd.entity);
> > > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > > +	mutex_destroy(&sensor->lock);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static const struct i2c_device_id ovm6211_id[] = {
> > > +	{ "ovm6211", 0 },
> > > +	{},
> > > +};
> > > +MODULE_DEVICE_TABLE(i2c, ovm6211_id);
> > > +
> > > +static const struct of_device_id ovm6211_dt_ids[] = {
> > > +	{ .compatible = "ovti,ovm6211" },
> > > +	{ /* sentinel */ }
> > > +};
> > > +MODULE_DEVICE_TABLE(of, ovm6211_dt_ids);
> > > +
> > > +static struct i2c_driver ovm6211_i2c_driver = {
> > > +	.driver = {
> > > +		.name  = "ovm6211",
> > > +		.of_match_table	= ovm6211_dt_ids,
> > > +	},
> > > +	.id_table = ovm6211_id,
> > 
> > Please remove ovm62211_id table unless you really need it.
> 
> OK.
> 
> > > +	.probe_new = ovm6211_probe,
> > > +	.remove   = ovm6211_remove,
> > > +};
> > > +
> > > +module_i2c_driver(ovm6211_i2c_driver);
> > > +
> > > +MODULE_AUTHOR("Petko Manolov <petko.manolov@konsulko.com>");
> > > +MODULE_DESCRIPTION("OVM6211 MIPI Camera Subdev Driver");
> > > +MODULE_LICENSE("GPL");
> > 
> > -- 
> > Kind regards,
> > 
> > Sakari Ailus
> 
> Thanks for the detailed review, Sakari, much appreciated.

You're welcome!

-- 
Kind regards,

Sakari Ailus

Re: [RFC PATCH 1/5] adds ovm6211 driver to staging

[Petko Manolov]

On 22-01-12 11:00:25, Sakari Ailus wrote:
> Hi Petko,
> 
> On Tue, Jan 04, 2022 at 05:30:27PM +0200, Petko Manolov wrote:
> > On 21-12-07 14:44:14, Sakari Ailus wrote:
> > > Hi Petko,
> > 
> > Hey Sakari.  I've subscribed to linux-media using my company email address.
> > Thanks to Google, i found your message in my SPAM folder.  Along with a whole
> > bunch of other linux-media, linux-kernel and netdev emails.  Not sure what's
> > wrong with the G men these days...
> 
> There are many ways to sort e-mail. Maybe they expect you to read that, too?
> :-)

Sending valid email to SPAM may be considered "unsorting". :)

> > > Thanks for the patchset.
> > > 
> > > You can squash the other patches into this one (Kconfig and Makefile
> > > changes).
> > > 
> > > Could you also add DT bindings (and CC Rob Herring and the devicetree list) in
> > > the future?
> > 
> > Yup, will do this in parallel with this patch series.
> > 
> > > On Sat, Dec 04, 2021 at 12:12:43AM +0200, Petko Manolov wrote:
> > > 
> > > Please add some more description, i.e. not just the subject line.
> > 
> > Uhm, ok.
> > 
> > > > Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
> > > > ---
> > > >  drivers/staging/media/i2c/ovm6211.c | 1156 +++++++++++++++++++++++++++
> > > 
> > > Why are you targetting the staging tree? We have a number of sensor drivers
> > > in the kernel proper already.
> > 
> > Because it is a new and relatively untested (by the general public) driver.
> 
> That doesn't suggest there's a need to target the staging. Bugs are of course
> possible but then they're simply fixed.
> 
> > 
> > > >  1 file changed, 1156 insertions(+)
> > > >  create mode 100644 drivers/staging/media/i2c/ovm6211.c
> > > > 
> > > > diff --git a/drivers/staging/media/i2c/ovm6211.c b/drivers/staging/media/i2c/ovm6211.c
> > > > new file mode 100644
> > > > index 000000000000..a89c5167a892
> > > > --- /dev/null
> > > > +++ b/drivers/staging/media/i2c/ovm6211.c
> > > > @@ -0,0 +1,1156 @@
> > > > +// SPDX-License-Identifier: GPL-2.0
> > > > +/*
> > > > + * Based on ov5640.c that lives in the same directory.
> > > 
> > > But we don't have drivers/staging/media/i2c yet?
> > > 
> > > > + *
> > > > + * Copyright (C) 2021 Petko Manolov <petko.manolov@konsulko.com>
> > > > + * Copyright (C) 2021 DEKA Research & Development Corp.
> > > > + */
> > > > +
> > > > +#define	DEBUG
> > > 
> > > Is this still meant to be here?
> > 
> > Nope, an omission on my part.
> > 
> > > > +
> > > > +#include <linux/clk.h>
> > > > +#include <linux/clk-provider.h>
> > > > +#include <linux/clkdev.h>
> > > > +#include <linux/ctype.h>
> > > 
> > > Do you need all the headers here?
> > 
> > Seems like the answer is yes, devm_clk_get() and clk_get_rate() definitions come
> > from these headers.
> 
> But linux/ctype.h?
> 
> You shouldn't need linux/clkdev.h nor linux/clk-provider.h either.
> 
> > 
> > > > +#include <linux/delay.h>
> > > > +#include <linux/device.h>
> > > > +#include <linux/gpio/consumer.h>
> > > > +#include <linux/i2c.h>
> > > > +#include <linux/init.h>
> 
> Please remove.
> 
> > > > +#include <linux/module.h>
> > > > +#include <linux/regmap.h>
> > > > +#include <linux/of_device.h>
> 
> This one, too.

All of the above are removed.

> > > > +#include <linux/regulator/consumer.h>
> > > > +#include <linux/slab.h>
> > > > +#include <linux/types.h>
> > > > +#include <media/v4l2-async.h>
> > > > +#include <media/v4l2-ctrls.h>
> > > > +#include <media/v4l2-device.h>
> > > > +#include <media/v4l2-event.h>
> > > > +#include <media/v4l2-fwnode.h>
> > > > +#include <media/v4l2-subdev.h>
> > > > +
> > > > +/* Min/max system clock (xvclk) frequencies */
> > > > +#define OVM6211_XVCLK_MIN	 6000000
> > > > +#define OVM6211_XVCLK_MAX	27000000
> > > > +
> > > > +/* begin of OVM6211 definitions */
> > > > +/* System Control */
> > > > +#define OVM6211_SC_MODE_SELECT		0x0100
> > > > +#define OVM6211_SC_SOFTWARE_RESET	0x0103
> > > > +#define OVM6211_SC_SCCB_ID1		0x0109
> > > > +#define OVM6211_SC_CHIP_ID_HIGH		0x300a
> > > > +#define OVM6211_SC_CHIP_ID_LOW		0x300b
> > > > +#define OVM6211_SC_REG0C		0x300c
> > > > +#define OVM6211_SC_REG10		0x3010
> > > > +#define OVM6211_SC_MIPI_PHY		0x3012
> > > > +#define OVM6211_SC_MIPI_PHY2		0x3013
> > > > +#define OVM6211_SC_MIPI_SC_CTRL0	0x3014
> > > > +#define OVM6211_SC_MIPI_SC_CTRL1	0x3015
> > > > +#define OVM6211_SC_CLKRST0		0x3016
> > > > +#define OVM6211_SC_CLKRST1		0x3017
> > > > +#define OVM6211_SC_CLKRST2		0x3018
> > > > +#define OVM6211_SC_CLKRST3		0x3019
> > > > +#define OVM6211_SC_CLKRST4		0x301a
> > > > +#define OVM6211_SC_CLKRST5		0x301b
> > > > +#define OVM6211_SC_CLKRST6		0x301c
> > > > +#define OVM6211_SC_CLOCK_SEL		0x301e
> > > > +#define OVM6211_SC_MISC_CTRL		0x301f
> > > > +#define OVM6211_SC_LOW_PWR_CTRL		0x3023
> > > > +#define OVM6211_SC_REG27		0x3027
> > > > +#define OVM6211_SC_GP_IO_IN1		0x3029
> > > > +#define OVM6211_SC_GP_IO_IN2		0x302a
> > > > +#define OVM6211_SC_SCCB_ID2		0x302b
> > > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD0	0x302c
> > > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD1	0x302d
> > > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD2	0x302e
> > > > +#define OVM6211_SC_AUTO_SLEEP_PERIOD3	0x302f
> > > > +#define OVM6211_SC_LP_CTRL0		0x3030
> > > > +#define OVM6211_SC_REG37		0x3037
> > > > +#define OVM6211_SC_REG3B		0x303b
> > > > +/* PLL Control */
> > > > +#define OVM6211_PLL_PLL0		0x3080
> > > > +#define OVM6211_PLL_PLL1		0x3081
> > > > +#define OVM6211_PLL_PLL2		0x3082
> > > > +#define OVM6211_PLL_PLL18		0x3098
> > > > +#define OVM6211_PLL_PLL19		0x3099
> > > > +#define OVM6211_PLL_PLL1A		0x309a
> > > > +#define OVM6211_PLL_PLL1B		0x309b
> > > > +#define OVM6211_PLL_PLL1C		0x309c
> > > > +#define OVM6211_PLL_PLL1D		0x309d
> > > > +#define OVM6211_PLL_PLL1E		0x309e
> > > > +#define OVM6211_PLL_PLL1F		0x309f
> > > > +#define OVM6211_PLL_VT_PIX_CLK_DIV	0x30b0
> > > > +#define OVM6211_PLL_VT_SYS_CLK_DIV	0x30b1
> > > > +#define OVM6211_PLL_MULTIPLIER		0x30b3
> > > > +#define OVM6211_PLL_PLL1_PRE_PLL_DIV	0x30b4
> > > > +#define OVM6211_PLL_PLL1_OP_PIX_CLK_DIV	0x30b5
> > > > +#define OVM6211_PLL_PLL1_OP_SYS_CLK_DIV	0x30b6
> > > > +/* SCCB and group hold */
> > > > +#define OVM6211_SB_SRB_CTRL		0x3106
> > > > +#define OVM6211_SB_SWITCH		0x31ff
> > > > +/* AEC/AGC */
> > > > +#define OVM6211_AEC_EXPO1		0x3500
> > > > +#define OVM6211_AEC_EXPO2		0x3501
> > > > +#define OVM6211_AEC_EXPO3		0x3502
> > > > +#define OVM6211_AEC_MANUAL		0x3503
> > > > +#define OVM6211_AGC_MAN_SNR_GAIN1	0x3504
> > > > +#define OVM6211_AGC_MAN_SNR_GAIN2	0x3505
> > > > +/* timing conrol registers */
> > > > +#define	OVM6211_TVTS_HI			0x380e
> > > > +#define	OVM6211_TVTS_LO			0x380f
> > > > +/*Strobe frame span registers*/
> > > > +#define OVM6211_STROBE_SPAN1		0x3b8d
> > > > +#define OVM6211_STROBE_SPAN2		0x3b8e
> > > > +#define OVM6211_STROBE_SPAN3		0x3b8f
> > > > +/* format control */
> > > > +#define OVM6211_DATA_MAX_H		0x4300
> > > > +#define OVM6211_DATA_MIN_H		0x4301
> > > > +#define OVM6211_CLIP_L			0x4302
> > > > +#define OVM6211_FORMAT_CTRL3		0x4303
> > > > +#define OVM6211_FORMAT_CTRL4		0x4304
> > > > +#define OVM6211_VSYNC_WIDTH_H		0x4311
> > > > +#define OVM6211_VSYNC_WIDTH_L		0x4312
> > > > +#define OVM6211_VSYNC_CTRL		0x4313
> > > > +#define OVM6211_VSYNC_DELAY1		0x4314
> > > > +#define OVM6211_VSYNC_DELAY2		0x4315
> > > > +#define OVM6211_VSYNC_DELAY3		0x4316
> > > > +#define OVM6211_TST_PATTERN_CTRL	0x4320
> > > > +/* MIPI */
> > > > +#define OVM6211_MIPI_CTRL00		0x4800
> > > > +#define OVM6211_MIPI_CTRL01		0x4801
> > > > +#define OVM6211_MIPI_CTRL02		0x4802
> > > > +#define OVM6211_MIPI_CTRL03		0x4803
> > > > +#define OVM6211_MIPI_CTRL04		0x4804
> > > > +#define OVM6211_MIPI_CTRL05		0x4805
> > > > +#define OVM6211_MIPI_CTRL06		0x4806
> > > > +#define OVM6211_MIPI_MAX_FRAME_COUNT_H	0x4810
> > > > +#define OVM6211_MIPI_MAX_FRAME_COUNT_L	0x4811
> > > > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_H	0x4812
> > > > +#define OVM6211_MIPI_SHORT_PKT_COUNTER_L	0x4813
> > > > +#define OVM6211_MIPI_CTRL14		0x4814
> > > > +#define OVM6211_MIPI_DT_SPKT		0x4815
> > > > +#define OVM6211_MIPI_REG_MAX_H		0x4835
> > > > +#define OVM6211_MIPI_REG_MAX_L		0x4836
> > > > +#define OVM6211_PCLK_PERIOD		0x4837
> > > > +#define OVM6211_WKUP_DLY		0x4838
> > > > +#define OVM6211_DIR_DLY			0x483a
> > > > +#define OVM6211_MIPI_LP_GPIO		0x483b
> > > > +#define OVM6211_MIPI_CTRL3C		0x483c
> > > > +#define OVM6211_T_TA_GO			0x483d
> > > > +#define OVM6211_T_TA_SURE		0x483e
> > > > +#define OVM6211_T_TA_GET		0x483f
> > > > +#define OVM6211_MIPI_CLIP_MAX_H		0x4846
> > > > +#define OVM6211_MIPI_CLIP_MAX_L		0x4847
> > > > +#define OVM6211_MIPI_CLIP_MIN_H		0x4848
> > > > +#define OVM6211_MIPI_CLIP_MIN_L		0x4848
> > > > +#define OVM6211_REG_INTR_MAN		0x4850
> > > > +#define OVM6211_REG_TX_WR		0x4851
> > > > +/* ISP top */
> > > > +#define OVM6211_ISP_CTRL00		0x5000
> > > > +#define OVM6211_ISP_CTRL01		0x5001
> > > > +#define OVM6211_ISP_CTRL02		0x5002
> > > > +#define OVM6211_ISP_CTRL03		0x5003
> > > > +#define OVM6211_ISP_CTRL04		0x5004
> > > > +#define OVM6211_ISP_CTRL05		0x5005
> > > > +#define OVM6211_ISP_CTRL06		0x5006
> > > > +#define OVM6211_ISP_CTRL07		0x5007
> > > > +#define OVM6211_ISP_CTRL08		0x5008
> > > > +#define OVM6211_ISP_CTRL09		0x5009
> > > > +/* window control */
> > > > +#define OVM6211_MAN_XSTART_OFF_H	0x5a00
> > > > +#define OVM6211_MAN_XSTART_OFF_L	0x5a01
> > > > +#define OVM6211_MAN_YSTART_OFF_H	0x5a02
> > > > +#define OVM6211_MAN_YSTART_OFF_L	0x5a03
> > > > +#define OVM6211_MAN_WIN_WIDTH_H		0x5a04
> > > > +#define OVM6211_MAN_WIN_WIDTH_L		0x5a05
> > > > +#define OVM6211_MAN_WIN_HEIGHT_H	0x5a06
> > > > +#define OVM6211_MAN_WIN_HEIGHT_L	0x5a07
> > > > +#define OVM6211_WIN_MAN			0x5a08
> > > > +
> > > > +#define	OVM6211_LAST_REG		0x5e08
> > > > +/* end of OVM6211 definitions */
> > > > +
> > > > +enum ovm6211_mode_id {
> > > > +	OVM6211_MODE_Y8_400_200 = 0,
> > > > +	OVM6211_MODE_Y8_400_400,
> > > > +	OVM6211_NUM_MODES,
> > > > +};
> > > > +
> > > > +struct ovm6211_pixfmt {
> > > > +	u32 code;
> > > > +	u32 colorspace;
> > > > +};
> > > > +
> > > > +static const struct ovm6211_pixfmt ovm6211_formats[] = {
> > > > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > > > +	{ MEDIA_BUS_FMT_Y8_1X8,   V4L2_COLORSPACE_RAW, },
> > > > +};
> > > > +
> > > > +enum ovm6211_framerate_ids {
> > > > +	OVM6211_10_FPS = 0,
> > > > +	OVM6211_15_FPS,
> > > > +	OVM6211_30_FPS,
> > > > +	OVM6211_45_FPS,
> > > > +	OVM6211_60_FPS,
> > > > +	OVM6211_NUM_FRAMERATES,
> > > > +};
> > > > +
> > > > +static const int ovm6211_framerates[] = {
> > > > +	[OVM6211_10_FPS] = 10,
> > > > +	[OVM6211_15_FPS] = 15,
> > > > +	[OVM6211_30_FPS] = 30,
> > > > +	[OVM6211_45_FPS] = 45,
> > > > +	[OVM6211_60_FPS] = 60,
> > > > +};
> > > > +
> > > > +/* regulator supplies */
> > > > +static const char * const ovm6211_supply_name[] = {
> > > > +	"dovdd",
> > > > +	"avdd",
> > > > +};
> > > > +
> > > > +#define OVM6211_NUM_SUPPLIES ARRAY_SIZE(ovm6211_supply_name)
> > > 
> > > I'd suggest to use plain ARRAY_SIZE() instead. This is just an unnecessary
> > > macro.
> > 
> > This resolves to '2', but i find that both, OVM6211_NUM_SUPPLIES and
> > ARRAY_SIZE(ovm6211_supply_name) look equally ugly to me. :)
> 
> Plain ARRAY_SIZE() doesn't lose the information what this is about --- it's
> easy to see whether the usage is correct or not. With the macro that's not the
> case.

ARRAY_SIZE() it is.

> > > > +
> > > > +static const struct regmap_config ovm6211_regmap_config = {
> > > > +	.reg_bits       = 16,
> > > > +	.val_bits       = 8,
> > > > +	.max_register   = OVM6211_LAST_REG,
> > > > +	.cache_type	= REGCACHE_NONE,
> > > > +};
> > > > +
> > > > +struct reg_value {
> > > > +	u16 reg_addr;
> > > > +	u8 val;
> > > > +	u8 mask;
> > > > +	u32 delay_ms;
> > > > +};
> > > > +
> > > > +struct ovm6211_mode_info {
> > > > +	enum ovm6211_mode_id id;
> > > > +	u32 width;
> > > > +	u32 height;
> > > > +	const struct reg_value *reg_data;
> > > > +	u32 reg_data_size;
> > > > +	u32 pixel_clock;
> > > > +};
> > > > +
> > > > +struct ovm6211_ctrls {
> > > > +	struct v4l2_ctrl_handler handler;
> > > > +	struct {
> > > > +		struct v4l2_ctrl *auto_exp;
> > > > +		struct v4l2_ctrl *exposure;
> > > > +	};
> > > > +	struct {
> > > > +		struct v4l2_ctrl *auto_gain;
> > > > +		struct v4l2_ctrl *gain;
> > > > +	};
> > > > +	struct v4l2_ctrl *brightness;
> > > > +	struct v4l2_ctrl *light_freq;
> > > > +	struct v4l2_ctrl *saturation;
> > > > +	struct v4l2_ctrl *contrast;
> > > > +	struct v4l2_ctrl *hue;
> > > > +	struct v4l2_ctrl *test_pattern;
> > > > +	struct v4l2_ctrl *link_freq;
> > > > +	struct v4l2_ctrl *pixel_clock;
> 
> Please only keep references to the ones you need. pixel_clock, for instance,
> remains unused.

Oops, i overlooked this one.  V5 material, then.

> > > > +};
> > > > +
> > > > +struct ovm6211_dev {
> > > > +	struct i2c_client *i2c_client;
> > > > +	struct regmap *regmap;
> > > > +	struct v4l2_subdev sd;
> > > > +	struct media_pad pad;
> > > > +	struct v4l2_fwnode_endpoint ep; /* the parsed DT endpoint info */
> > > > +	struct clk *xclk; /* system clock to OVM6211 */
> > > > +	u32 xclk_freq;
> > > > +
> > > > +	struct regulator_bulk_data supplies[OVM6211_NUM_SUPPLIES];
> > > > +	struct gpio_desc *reset_gpio;
> > > > +	struct gpio_desc *pwdn_gpio;
> > > > +
> > > > +	struct mutex lock;
> > > > +
> > > > +	struct v4l2_mbus_framefmt fmt;
> > > > +
> > > > +	const struct ovm6211_mode_info *cur_mode;
> > > > +	enum ovm6211_framerate_ids cur_fr_id;
> > > > +	struct v4l2_fract frame_interval;
> > > > +
> > > > +	struct ovm6211_ctrls ctrls;
> > > > +
> > > > +	u32 exposure;
> > > > +	bool pending_mode_change;
> > > > +	bool pending_fi_change;
> > > > +	bool streaming;
> > > > +};
> > > > +
> > > > +static inline struct ovm6211_dev *to_ovm6211_dev(struct v4l2_subdev *sd)
> > > > +{
> > > > +	return container_of(sd, struct ovm6211_dev, sd);
> > > > +}
> > > > +
> > > > +static inline struct v4l2_subdev *ctrl_to_sd(struct v4l2_ctrl *ctrl)
> > > > +{
> > > > +	return &container_of(ctrl->handler, struct ovm6211_dev,
> > > > +			     ctrls.handler)->sd;
> > > > +}
> > > > +
> > > > +static const struct reg_value ovm6211_init_y8_400_400[] = {
> > > > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > > > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > > > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > > > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > > > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > > > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > > > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > > > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > > > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > > > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > > > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > > > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > > > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > > > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > > > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > > > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > > > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > > > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > > > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > > > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > > > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > > > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > > > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > > > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0}, {0x3808, 0x01, 0, 0},
> > > > +	{0x3809, 0x90, 0, 0}, {0x380a, 0x01, 0, 0}, {0x380b, 0x90, 0, 0},
> > > > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x03, 0, 0},
> > > > +	{0x380f, 0x6c, 0, 0}, {0x3810, 0x00, 0, 0}, {0x3811, 0x04, 0, 0},
> > > > +	{0x3812, 0x00, 0, 0}, {0x3813, 0x04, 0, 0}, {0x3814, 0x11, 0, 0},
> > > > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > > > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > > > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > > > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > > > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > > > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > > > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > > > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > > > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > > > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > > > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > > > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > > > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > > > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > > > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > > > +};
> > > > +
> > > > +static const struct reg_value ovm6211_init_y8_400_200[] = {
> > > > +	{0x0103, 0x01, 0, 0}, {0x0100, 0x00, 0, 0}, {0x3005, 0x08, 0, 0},
> > > > +	{0x3013, 0x12, 0, 0}, {0x3014, 0x04, 0, 0}, {0x3016, 0x10, 0, 0},
> > > > +	{0x3017, 0x00, 0, 0}, {0x3018, 0x00, 0, 0}, {0x301a, 0x00, 0, 0},
> > > > +	{0x301b, 0x00, 0, 0}, {0x301c, 0x00, 0, 0}, {0x3037, 0xf0, 0, 0},
> > > > +	{0x3080, 0x01, 0, 0}, {0x3081, 0x00, 0, 0}, {0x3082, 0x01, 0, 0},
> > > > +	{0x3098, 0x04, 0, 0}, {0x3099, 0x28, 0, 0}, {0x309a, 0x06, 0, 0},
> > > > +	{0x309b, 0x04, 0, 0}, {0x309c, 0x00, 0, 0}, {0x309d, 0x00, 0, 0},
> > > > +	{0x309e, 0x01, 0, 0}, {0x309f, 0x00, 0, 0}, {0x30b0, 0x08, 0, 0},
> > > > +	{0x30b1, 0x02, 0, 0}, {0x30b2, 0x00, 0, 0}, {0x30b3, 0x28, 0, 0},
> > > > +	{0x30b4, 0x02, 0, 0}, {0x30b5, 0x00, 0, 0}, {0x3106, 0xd9, 0, 0},
> > > > +	{0x3500, 0x00, 0, 0}, {0x3501, 0x1b, 0, 0}, {0x3502, 0x20, 0, 0},
> > > > +	{0x3503, 0x07, 0, 0}, {0x3509, 0x10, 0, 0}, {0x350b, 0x10, 0, 0},
> > > > +	{0x3600, 0xfc, 0, 0}, {0x3620, 0xb7, 0, 0}, {0x3621, 0x05, 0, 0},
> > > > +	{0x3626, 0x31, 0, 0}, {0x3627, 0x40, 0, 0}, {0x3632, 0xa3, 0, 0},
> > > > +	{0x3633, 0x34, 0, 0}, {0x3634, 0x40, 0, 0}, {0x3636, 0x00, 0, 0},
> > > > +	{0x3660, 0x80, 0, 0}, {0x3662, 0x03, 0, 0}, {0x3664, 0xf0, 0, 0},
> > > > +	{0x366a, 0x10, 0, 0}, {0x366b, 0x06, 0, 0}, {0x3680, 0xf4, 0, 0},
> > > > +	{0x3681, 0x50, 0, 0}, {0x3682, 0x00, 0, 0}, {0x3708, 0x20, 0, 0},
> > > > +	{0x3709, 0x40, 0, 0}, {0x370d, 0x03, 0, 0}, {0x373b, 0x02, 0, 0},
> > > > +	{0x373c, 0x08, 0, 0}, {0x3742, 0x00, 0, 0}, {0x3744, 0x16, 0, 0},
> > > > +	{0x3745, 0x08, 0, 0}, {0x3781, 0xfc, 0, 0}, {0x3788, 0x00, 0, 0},
> > > > +	{0x3800, 0x00, 0, 0}, {0x3801, 0x04, 0, 0}, {0x3802, 0x00, 0, 0},
> > > > +	{0x3803, 0x04, 0, 0}, {0x3804, 0x01, 0, 0}, {0x3805, 0x9b, 0, 0},
> > > > +	{0x3806, 0x01, 0, 0}, {0x3807, 0x9b, 0, 0},
> > > > +	{0x3808, 0x01, 0, 0},	// W
> > > > +	{0x3809, 0x90, 0, 0},	// W
> > > > +	{0x380a, 0x00, 0, 0},	// H
> > > > +	{0x380b, 0xc8, 0, 0},	// H
> 
> /* C comments, please */

Done.

> > > > +	{0x380c, 0x05, 0, 0}, {0x380d, 0xf2, 0, 0}, {0x380e, 0x0d, 0, 0},
> > > > +	{0x380f, 0xb0, 0, 0},
> > > > +	{0x3810, 0x00, 0, 0},	// W off
> > > > +	{0x3811, 0x04, 0, 0},	// W off: 4 + (400 - x_width)/2
> > > > +	{0x3812, 0x00, 0, 0},	// H off
> > > > +	{0x3813, 0x9a, 0, 0},	// H off: 4 + (400 - y_height)/2
> > > > +	{0x3814, 0x11, 0, 0},
> > > > +	{0x3815, 0x11, 0, 0}, {0x3820, 0x00, 0, 0}, {0x3821, 0x00, 0, 0},
> > > > +	{0x382b, 0xfa, 0, 0}, {0x382f, 0x04, 0, 0}, {0x3832, 0x00, 0, 0},
> > > > +	{0x3833, 0x05, 0, 0}, {0x3834, 0x00, 0, 0}, {0x3835, 0x05, 0, 0},
> > > > +	{0x3882, 0x04, 0, 0}, {0x3883, 0x00, 0, 0}, {0x38a4, 0x10, 0, 0},
> > > > +	{0x38a5, 0x00, 0, 0}, {0x38b1, 0x03, 0, 0}, {0x3b80, 0x00, 0, 0},
> > > > +	{0x3b81, 0xff, 0, 0}, {0x3b82, 0x10, 0, 0}, {0x3b83, 0x00, 0, 0},
> > > > +	{0x3b84, 0x08, 0, 0}, {0x3b85, 0x00, 0, 0}, {0x3b86, 0x01, 0, 0},
> > > > +	{0x3b87, 0x00, 0, 0}, {0x3b88, 0x00, 0, 0}, {0x3b89, 0x00, 0, 0},
> > > > +	{0x3b8a, 0x00, 0, 0}, {0x3b8b, 0x05, 0, 0}, {0x3b8c, 0x00, 0, 0},
> > > > +	{0x3b8d, 0x00, 0, 0}, {0x3b8e, 0x01, 0, 0}, {0x3b8f, 0xb2, 0, 0},
> > > > +	{0x3b94, 0x05, 0, 0}, {0x3b95, 0xf2, 0, 0}, {0x3b96, 0xc0, 0, 0},
> > > > +	{0x4004, 0x04, 0, 0}, {0x404e, 0x01, 0, 0}, {0x4801, 0x0f, 0, 0},
> > > > +	{0x4806, 0x0f, 0, 0}, {0x4837, 0x43, 0, 0}, {0x5a08, 0x00, 0, 0},
> > > > +	{0x5a01, 0x00, 0, 0}, {0x5a03, 0x00, 0, 0}, {0x5a04, 0x10, 0, 0},
> > > > +	{0x5a05, 0xa0, 0, 0}, {0x5a06, 0x0c, 0, 0}, {0x5a07, 0x78, 0, 0},
> > > > +};
> > > > +
> > > > +/* power-on sensor init reg table */
> > > > +static const struct ovm6211_mode_info *ovm6211_mode_init_data;
> 
> Used in probe only. Please remove.

Removed.

> > > > +
> > > > +static struct ovm6211_mode_info
> > > > +ovm6211_mode_data[OVM6211_NUM_MODES] = {
> > > > +	{OVM6211_MODE_Y8_400_200,
> > > > +	 400, 200,
> > > > +	 ovm6211_init_y8_400_200,
> > > > +	 ARRAY_SIZE(ovm6211_init_y8_400_200),
> > > > +	 400 * 400 * 60 * 2,
> > > > +	},
> > > > +	{OVM6211_MODE_Y8_400_400,
> > > > +	 400, 400,
> > > > +	 ovm6211_init_y8_400_400,
> > > > +	 ARRAY_SIZE(ovm6211_init_y8_400_400),
> > > > +	 400 * 400 * 60 * 2,
> > > > +	},
> > > > +};
> > > > +
> > > > +static const s64 link_freq_menu_items[] = {
> > > > +	0,
> > > > +};
> > > > +
> > > > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > > > +static int ovm6211_get_register(struct v4l2_subdev *sd,
> > > > +				struct v4l2_dbg_register *reg)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	struct regmap *regmap = sensor->regmap;
> > > > +	unsigned int val = 0;
> > > > +	int ret;
> > > > +
> > > > +	ret = regmap_read(regmap, reg->reg, &val);
> > > > +	reg->val = val;
> > > > +	reg->size = 1;
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_set_register(struct v4l2_subdev *sd,
> > > > +				const struct v4l2_dbg_register *reg)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	struct regmap *regmap = sensor->regmap;
> > > > +
> > > > +	return regmap_write(regmap, reg->reg, reg->val & 0xff);
> > > > +}
> > > > +#endif
> > > > +
> > > > +static int ovm6211_write_reg(struct ovm6211_dev *sensor, u16 reg, u8 val)
> > > > +{
> > > > +	struct i2c_client *client = sensor->i2c_client;
> > > > +	struct regmap *regmap = sensor->regmap;
> > > > +	int ret;
> > > > +
> > > > +	ret = regmap_write(regmap, reg, val);
> > > > +	if (ret < 0)
> > > > +		dev_err(&client->dev, "error writing reg %u\n", reg);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_read_reg(struct ovm6211_dev *sensor, u16 reg, u8 *val)
> > > > +{
> > > > +	struct i2c_client *client = sensor->i2c_client;
> > > > +	struct regmap *regmap = sensor->regmap;
> > > > +	unsigned int r;
> > > > +	int ret;
> > > > +
> > > > +	ret = regmap_read(regmap, reg, &r);
> > > > +	if (ret < 0)
> > > > +		dev_err(&client->dev, "error reading reg %u\n", reg);
> > > > +	*val = r & 0xff;
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_mod_reg(struct ovm6211_dev *sensor, u16 reg, u8 mask, u8 val)
> > > > +{
> > > > +	u8 readval;
> > > > +	int ret;
> > > > +
> > > > +	ret = ovm6211_read_reg(sensor, reg, &readval);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	readval &= ~mask;
> > > > +	val &= mask;
> > > > +	val |= readval;
> > > > +
> > > > +	return ovm6211_write_reg(sensor, reg, val);
> > > > +}
> > > > +
> > > > +static int ovm6211_load_regs(struct ovm6211_dev *sensor,
> > > > +			     const struct ovm6211_mode_info *mode)
> > > > +{
> > > > +	const struct reg_value *regs = mode->reg_data;
> > > > +	unsigned int i;
> > > > +	u32 delay_ms;
> > > > +	u16 reg_addr;
> > > > +	u8 mask, val;
> > > > +	int ret = 0;
> > > > +
> > > > +	for (i = 0; i < mode->reg_data_size; ++i, ++regs) {
> > > > +		delay_ms = regs->delay_ms;
> > > > +		reg_addr = regs->reg_addr;
> > > > +		val = regs->val;
> > > > +		mask = regs->mask;
> > > > +		if (mask)
> > > > +			ret = ovm6211_mod_reg(sensor, reg_addr, mask, val);
> > > > +		else
> > > > +			ret = ovm6211_write_reg(sensor, reg_addr, val);
> > > > +		if (ret)
> > > > +			break;
> > > > +
> > > > +		if (delay_ms) {
> > > > +			usleep_range(1000 * delay_ms, 1000 * delay_ms + 100);
> > > > +		}
> > > > +	}
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static void ovm6211_soft_reset(struct ovm6211_dev *sensor)
> > > > +{
> > > > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x01);
> > > > +	usleep_range(5000, 9000);
> > > > +	ovm6211_write_reg(sensor, OVM6211_SC_SOFTWARE_RESET, 0x00);
> > > > +}
> > > > +
> > > > +static int ovm6211_set_exposure(struct ovm6211_dev *sensor, u32 exposure)
> > > > +{
> > > > +	u32 ce;
> > > > +	u8 v;
> > > > +
> > > > +	ovm6211_read_reg(sensor, OVM6211_TVTS_HI, &v);
> > > > +	ce = v << 8;
> > > > +	ovm6211_read_reg(sensor, OVM6211_TVTS_LO, &v);
> > > > +	ce |= v;
> > > > +	ce -= 4;
> > > > +
> > > > +	if (ce < exposure)
> > > > +		exposure = ce;
> > > > +
> > > > +	ovm6211_mod_reg(sensor, OVM6211_AEC_MANUAL, 1, 1);
> > > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO1, (exposure >> 12) & 0x0f);
> > > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO2, (exposure >>  4) & 0xff);
> > > > +	ovm6211_write_reg(sensor, OVM6211_AEC_EXPO3, (exposure <<  4) & 0xf0);
> > > > +
> > > > +	/* set strobe width equal to exposure time */
> > > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN1, (exposure >> 16) & 0xff);
> > > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN2, (exposure >>  8) & 0xff);
> > > > +	ovm6211_write_reg(sensor, OVM6211_STROBE_SPAN3, (exposure)       & 0xff);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int internal_set_stream(struct ovm6211_dev *sensor, bool on)
> > > > +{
> > > > +	u8 hi, lo;
> > > > +
> > > > +	if (sensor->pending_fi_change == false)
> > > > +		goto stream;
> > > > +
> > > > +	switch (sensor->cur_fr_id) {
> > > > +	case OVM6211_10_FPS:
> > > > +		hi = 0x14;
> > > > +		lo = 0x88;
> > > > +		break;
> > > > +	case OVM6211_15_FPS:
> > > > +		hi = 0x0d;
> > > > +		lo = 0xb0;
> > > > +		break;
> > > > +	case OVM6211_30_FPS:
> > > > +		hi = 0x06;
> > > > +		lo = 0xd8;
> > > > +		break;
> > > > +	case OVM6211_45_FPS:
> > > > +		hi=0x04;
> > > 
> > > Spaces around '=', please.
> > 
> > Yeah, this one has slipped through as well.
> > 
> > > > +		lo = 0x90;
> > > > +		break;
> > > > +	case OVM6211_60_FPS:
> > > > +		hi=0x03;
> > > > +		lo = 0x6c;
> > > > +		break;
> > > > +	case OVM6211_NUM_FRAMERATES:
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	sensor->pending_fi_change = false;
> > > > +	ovm6211_write_reg(sensor, OVM6211_TVTS_HI, hi);
> > > > +	ovm6211_write_reg(sensor, OVM6211_TVTS_LO, lo);
> > > > +stream:
> > > > +	ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 0);
> > > > +	if (on) {
> > > > +		usleep_range(4000, 5000);
> > > > +		if (sensor->exposure)
> > > > +			ovm6211_set_exposure(sensor, sensor->exposure);
> > > > +		ovm6211_write_reg(sensor, OVM6211_SC_MODE_SELECT, 1);
> > > > +		sensor->streaming = true;
> > > > +	} else {
> > > > +		sensor->streaming = false;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static struct ovm6211_mode_info *ovm6211_find_mode(int w, int h)
> 
> This function only has a single user. Please call v4l2_find_nearest_size()
> directly instead.

Thought a little bit and decided against it.  ovm6211_find_mode() is a
descriptive anough as a name and the compiler will inline the referrence anyway.
Using v4l2_find_nearest_size() with all arguments is going to make the code
rather ugly.

> > > > +{
> > > > +	return v4l2_find_nearest_size(ovm6211_mode_data,
> > > > +				      ARRAY_SIZE(ovm6211_mode_data),
> > > > +				      width, height, w, h);
> > > > +}
> > > > +
> > > > +static int ovm6211_set_mode(struct ovm6211_dev *sensor)
> > > > +{
> > > > +	const struct ovm6211_mode_info *mode = sensor->cur_mode;
> > > > +
> > > > +	ovm6211_soft_reset(sensor);
> > > > +	ovm6211_load_regs(sensor, mode);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +/* --------------- Subdev Operations --------------- */
> > > > +
> > > > +static int ovm6211_get_fmt(struct v4l2_subdev *sd,
> > > > +			   struct v4l2_subdev_state *state,
> > > > +			   struct v4l2_subdev_format *format)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	struct v4l2_mbus_framefmt *fmt;
> > > > +
> > > > +	if (format->pad != 0)
> > > > +		return -EINVAL;
> > > > +
> > > > +	mutex_lock(&sensor->lock);
> > > > +
> > > > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > > > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > > > +		format->format = *fmt;
> > > > +	} else {
> > > > +		/* these are hardcoded as we don't support anything else */
> > > > +		format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > > > +		format->format.field = V4L2_FIELD_NONE;
> > > > +		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > > > +		format->format.width = sensor->cur_mode->width;
> > > > +		format->format.height = sensor->cur_mode->height;
> > > > +	}
> > > > +
> > > > +	mutex_unlock(&sensor->lock);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
> > > > +{
> > > > +	u32 s, fmt, fps, ret;
> > > > +
> > > > +	/* x * y * [1|2] * y8/y10 * fps */
> > > > +	s = nm->width * nm->height;
> > > > +	fmt = 1;
> > > > +	fps = ovm6211_framerates[sensor->cur_fr_id];
> > > > +	ret = s * fmt * fps * 2;
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_set_fmt(struct v4l2_subdev *sd,
> > > > +			   struct v4l2_subdev_state *state,
> > > > +			   struct v4l2_subdev_format *format)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	struct v4l2_mbus_framefmt *fmt = &format->format;
> > > > +	struct ovm6211_mode_info *mode;
> > > > +
> > > > +	if (format->pad != 0)
> 
> The caller will have checked this already (assuming there's just a single
> pad). Same in get_fmt.

Removed

> > > > +		return -EINVAL;
> > > > +
> > > > +	if (sensor->streaming)
> 
> This check should be done when the mutex is taken.

Done.

> > > > +		return -EBUSY;
> > > > +
> > > > +	mutex_lock(&sensor->lock);
> > > > +
> > > > +	/* these are hardcoded as we don't support anything else */
> > > > +	format->format.colorspace  = V4L2_COLORSPACE_RAW;
> > > > +	format->format.field = V4L2_FIELD_NONE;
> > > > +	format->format.code = MEDIA_BUS_FMT_Y8_1X8;
> > > > +	mode = ovm6211_find_mode(format->format.width, format->format.height);
> > > > +	format->format.width = mode->width;
> > > > +	format->format.height = mode->height;
> > > > +
> > > > +	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > > > +		fmt = v4l2_subdev_get_try_format(&sensor->sd, state, format->pad);
> > > > +		*fmt = format->format;
> > > > +		goto out;
> > > > +	}
> > > > +	/* V4L2_SUBDEV_FORMAT_TRY_ACTIVE */
> > > > +	sensor->cur_mode = mode;
> > > > +out:
> > > > +	mutex_unlock(&sensor->lock);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +/*
> > > > + * Sensor Controls.
> > > > + */
> > > > +
> > > > +static int ovm6211_set_ctrl_exposure(struct ovm6211_dev *sensor, enum
> > > > +				     v4l2_exposure_auto_type auto_exposure)
> > > > +{
> > > > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > > > +
> > > > +	if (auto_exposure == V4L2_EXPOSURE_AUTO) {
> > > > +		sensor->exposure = 0;
> > > > +	} else {
> > > > +		sensor->exposure = ctrls->exposure->val;
> > > > +		ovm6211_set_exposure(sensor, sensor->exposure);
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ovm6211_set_ctrl_gain(struct ovm6211_dev *sensor, bool auto_gain)
> > > > +{
> > > 
> > > Hmm. Is something missing here?
> > 
> > Nope, just unimplemented.  I might remove it altogether or keep it here as a
> > placeholder.
> 
> Please either remove or add the implementation. This should be more or less
> trivial to implement though.

It's removed for now.

> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ovm6211_s_ctrl(struct v4l2_ctrl *ctrl)
> > > > +{
> > > > +	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	int ret;
> > > > +
> > > > +	/* v4l2_ctrl_lock() locks our own mutex */
> > > > +
> > > > +	/*
> > > > +	 * If the device is not powered up by the host driver do
> > > > +	 * not apply any controls to H/W at this time. Instead
> > > > +	 * the controls will be restored right after power-up.
> > > > +	 */
> > > > +	switch (ctrl->id) {
> > > > +	case V4L2_CID_GAIN:
> > > > +		ret = ovm6211_set_ctrl_gain(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_EXPOSURE_AUTO:
> > > > +		ret = ovm6211_set_ctrl_exposure(sensor, ctrl->val);
> > > > +		break;
> > > > +#if 0
> > > 
> > > Why?
> > 
> > Some of these are not supported by the sensor, some were not used by the user
> > space.  I'll just remove them.
> 
> Sounds good.
> 
> > 
> > > > +	case V4L2_CID_AUTO_WHITE_BALANCE:
> > > > +		ret = ovm6211_set_ctrl_white_balance(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_HUE:
> > > > +		ret = ovm6211_set_ctrl_hue(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_CONTRAST:
> > > > +		ret = ovm6211_set_ctrl_contrast(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_SATURATION:
> > > > +		ret = ovm6211_set_ctrl_saturation(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_TEST_PATTERN:
> > > > +		ret = ovm6211_set_ctrl_test_pattern(sensor, ctrl->val);
> > > > +		break;
> > > > +	case V4L2_CID_POWER_LINE_FREQUENCY:
> > > > +		ret = ovm6211_set_ctrl_light_freq(sensor, ctrl->val);
> > > > +		break;
> > > > +#endif
> > > > +	case V4L2_CID_LINK_FREQ:
> > > > +		return 0;
> > > > +	case V4L2_CID_PIXEL_RATE:
> > > > +		return 0;
> > > > +	default:
> > > > +		ret = -EINVAL;
> > > > +		break;
> > > > +	}
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static const struct v4l2_ctrl_ops ovm6211_ctrl_ops = {
> > > > +	.s_ctrl = ovm6211_s_ctrl,
> > > > +};
> > > > +
> > > > +static int ovm6211_init_controls(struct ovm6211_dev *sensor)
> > > > +{
> > > > +	const struct v4l2_ctrl_ops *ops = &ovm6211_ctrl_ops;
> > > > +	struct ovm6211_ctrls *ctrls = &sensor->ctrls;
> > > > +	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
> > > > +	int ret;
> > > > +
> > > > +	v4l2_ctrl_handler_init(hdl, 32);
> > > 
> > > This number should be more or less the number of controls.
> > 
> > OK.
> > 
> > > > +
> > > > +	/* we can use our own mutex for the ctrl lock */
> > > > +	hdl->lock = &sensor->lock;
> > > > +
> > > > +	ctrls->auto_exp = v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_EXPOSURE_AUTO,
> > > > +						 V4L2_EXPOSURE_MANUAL, 0,
> > > > +						 V4L2_EXPOSURE_AUTO);
> > > > +	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
> > > > +					    0, 65535, 1, 0);
> > > > +	ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAIN,
> > > > +					0, 1023, 1, 0);
> > > > +
> > > > +	v4l2_ctrl_auto_cluster(3, &ctrls->auto_exp, 0, false);
> > > > +
> > > > +	ctrls->saturation = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_SATURATION,
> > > > +					      0, 255, 1, 64);
> > > > +	ctrls->hue = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HUE,
> > > > +				       0, 359, 1, 0);
> > > > +	ctrls->contrast = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST,
> > > > +					    0, 255, 1, 0);
> > > > +	ctrls->light_freq =
> > > > +		v4l2_ctrl_new_std_menu(hdl, ops,
> > > > +				       V4L2_CID_POWER_LINE_FREQUENCY,
> > > > +				       V4L2_CID_POWER_LINE_FREQUENCY_AUTO, 0,
> > > > +				       V4L2_CID_POWER_LINE_FREQUENCY_50HZ);
> > > > +	ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
> > > > +						  0, 0, link_freq_menu_items);
> > > > +	ctrls->pixel_clock = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_PIXEL_RATE,
> > > > +						    1, INT_MAX, 1, 38400000);
> > > > +
> > > > +	if (hdl->error) {
> > > > +		ret = hdl->error;
> > > > +		goto free_ctrls;
> > > > +	}
> > > > +
> > > > +	ctrls->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > > > +	ctrls->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
> > > > +
> > > > +	sensor->sd.ctrl_handler = hdl;
> > > > +	return 0;
> > > > +
> > > > +free_ctrls:
> > > > +	v4l2_ctrl_handler_free(hdl);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_g_frame_interval(struct v4l2_subdev *sd,
> > > > +				    struct v4l2_subdev_frame_interval *fi)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +
> > > > +	mutex_lock(&sensor->lock);
> > > > +	fi->interval = sensor->frame_interval;
> > > > +	mutex_unlock(&sensor->lock);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int internal_set_frame_interval(struct ovm6211_dev *sensor, struct
> > > > +				       v4l2_subdev_frame_interval *fi)
> > > > +{
> > > > +	u32 fr_rate;
> > > > +	int i, max, ret = -EINVAL;
> > > > +
> > > > +	if (fi->interval.numerator == 0)
> > > > +		goto out;
> > > > +
> > > > +	fr_rate = fi->interval.denominator / fi->interval.numerator;
> > > > +
> > > > +	max = ARRAY_SIZE(ovm6211_framerates);
> > > > +	for (i = 0; i < max; i++) {
> > > > +		if (ovm6211_framerates[i] == fr_rate)
> > > > +			break;
> > > > +	}
> > > > +
> > > > +	if (i == max)
> > > > +		goto out;
> > > > +
> > > > +	sensor->cur_fr_id = i;
> > > > +	sensor->frame_interval = fi->interval;
> > > > +	ret = 0;
> > > > +out:
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_s_frame_interval(struct v4l2_subdev *sd,
> > > > +				    struct v4l2_subdev_frame_interval *fi)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	int ret;
> > > > +
> > > > +	mutex_lock(&sensor->lock);
> > > > +	ret = internal_set_frame_interval(sensor, fi);
> > > > +	sensor->pending_fi_change = true;
> > > > +	mutex_unlock(&sensor->lock);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_enum_mbus_code(struct v4l2_subdev *sd,
> > > > +				  struct v4l2_subdev_state *state,
> > > > +				  struct v4l2_subdev_mbus_code_enum *code)
> > > > +{
> > > > +	if (code->pad != 0)
> > > > +		return -EINVAL;
> > > 
> > > This check can be dropped, the caller has done it already (I assume you
> > > have a single pad).
> > 
> > OK.
> > 
> > > > +	if (code->index >= ARRAY_SIZE(ovm6211_formats))
> > > > +		return -EINVAL;
> > > > +
> > > > +	code->code = ovm6211_formats[code->index].code;
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int ovm6211_s_stream(struct v4l2_subdev *sd, int enable)
> > > > +{
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +	int ret = 0;
> > > > +
> > > > +	mutex_lock(&sensor->lock);
> > > > +
> > > > +	if (enable)
> > > > +		ret = ovm6211_set_mode(sensor);
> > > > +	internal_set_stream(sensor, enable);
> > > > +
> > > > +	mutex_unlock(&sensor->lock);
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_set_power(struct v4l2_subdev *sd, int on)
> > > > +{
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static const struct v4l2_subdev_core_ops ovm6211_core_ops = {
> > > > +#ifdef CONFIG_VIDEO_ADV_DEBUG
> > > > +	.g_register = ovm6211_get_register,
> > > > +	.s_register = ovm6211_set_register,
> > > > +#endif
> > > > +	.s_power = ovm6211_set_power,
> > > > +};
> > > > +
> > > > +static const struct v4l2_subdev_video_ops ovm6211_video_ops = {
> > > > +	.g_frame_interval = ovm6211_g_frame_interval,
> > > > +	.s_frame_interval = ovm6211_s_frame_interval,
> > > > +	.s_stream = ovm6211_s_stream,
> > > > +};
> > > > +
> > > > +static const struct v4l2_subdev_pad_ops ovm6211_pad_ops = {
> > > > +	.enum_mbus_code = ovm6211_enum_mbus_code,
> > > > +	.get_fmt = ovm6211_get_fmt,
> > > > +	.set_fmt = ovm6211_set_fmt,
> > > > +};
> > > > +
> > > > +static const struct v4l2_subdev_ops ovm6211_subdev_ops = {
> > > > +	.core = &ovm6211_core_ops,
> > > > +	.video = &ovm6211_video_ops,
> > > > +	.pad = &ovm6211_pad_ops,
> > > > +};
> > > > +
> > > > +static int ovm6211_get_regulators(struct ovm6211_dev *sensor)
> > > > +{
> > > > +	int i;
> > > 
> > > unsigned int, please.
> > 
> > Why?  It isn't like OVM6211_NUM_SUPPLIES will ever be more than single digit
> > number.
> 
> It's better to compare two unsigned values rather than one signed and another
> unsigned.

Oh well, done.

> > > > +
> > > > +	for (i = 0; i < OVM6211_NUM_SUPPLIES; i++)
> > > > +		sensor->supplies[i].supply = ovm6211_supply_name[i];
> > > > +
> > > > +	return devm_regulator_bulk_get(&sensor->i2c_client->dev,
> > > > +				       OVM6211_NUM_SUPPLIES,
> > > > +				       sensor->supplies);
> > > > +}
> > > > +
> > > > +static int ovm6211_check_chip_id(struct ovm6211_dev *sensor)
> > > > +{
> > > > +	struct i2c_client *client = sensor->i2c_client;
> > > > +	struct regmap *regmap = sensor->regmap;
> > > > +	unsigned int cid;
> > > > +	int ret = 0;
> > > > +
> > > > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_HIGH, &cid);
> > > > +	if (ret || cid != 0x67) {
> > > > +		ret = ENXIO;
> > > > +		goto err;
> > > > +	}
> > > > +
> > > > +	ret = regmap_read(regmap, OVM6211_SC_CHIP_ID_LOW, &cid);
> > > > +	if (ret || cid != 0x10) {
> > > > +		ret = -ENXIO;
> > > > +		goto err;
> > > > +	}
> > > > +
> > > > +	ret = regmap_read(regmap, OVM6211_SC_REG0C, &cid);
> > > > +	if (ret)
> > > > +		goto err;
> > > > +
> > > > +	dev_info(&client->dev,"found OVM6211, sub revision: 0x%02X\n", cid);
> > > > +	return 0;
> > > > +err:
> > > > +	dev_err(&client->dev, "failed to detect OVM6211\n");
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_probe(struct i2c_client *client)
> > > > +{
> > > > +	struct device *dev = &client->dev;
> > > > +	struct fwnode_handle *endpoint;
> > > > +	struct ovm6211_dev *sensor;
> > > > +	struct v4l2_mbus_framefmt *fmt;
> > > > +	int ret;
> > > > +
> > > > +	sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
> > > > +	if (!sensor)
> > > > +		return -ENOMEM;
> > > > +
> > > > +	sensor->i2c_client = client;
> > > > +
> > > > +	/*
> > > > +	 * default init sequence initialize sensor to
> > > > +	 * YUV422 UYVY VGA@30fps
> > > > +	 */
> > > > +	fmt = &sensor->fmt;
> > > > +	fmt->code = MEDIA_BUS_FMT_Y8_1X8;
> > > > +	fmt->colorspace = V4L2_COLORSPACE_RAW;
> > > > +	fmt->field = V4L2_FIELD_NONE;
> > > > +	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > > +	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
> > > > +	fmt->width = 400;
> > > > +	fmt->height = 200;
> > > > +
> > > > +	sensor->frame_interval.numerator = 1;
> > > > +	sensor->frame_interval.denominator = ovm6211_framerates[OVM6211_45_FPS];
> > > > +	sensor->cur_fr_id = OVM6211_45_FPS;
> > > > +	ovm6211_mode_init_data = &ovm6211_mode_data[OVM6211_MODE_Y8_400_200];
> > > > +	sensor->cur_mode = ovm6211_mode_init_data;
> > > > +
> > > > +	sensor->ep.bus_type = V4L2_MBUS_CSI2_DPHY;
> > > > +	endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
> > > 
> > > Over 80, please wrap. Same for other such lines (maybe apart from tables
> > > etc.).
> > 
> > Ah, i really agree with Linus about this one: https://lkml.org/lkml/2020/5/29/1038
> > 
> > Extensive line breaking is such a pain when reading the code.  Besides, who is
> > really using 80x25 these days?
> 
> Still the coding style encourages lines no longer than 80 albeit in some cases
> other factors may be more important than that.

Getting the code unnecessary ugly only to satisfy a requirement that is fairly
old, isn't justifying the whole thing.  I do agree that lines 200 character long
are too much to digest, but that's not the case here.

> > > > +	if (!endpoint) {
> > > > +		dev_err(dev, "endpoint node not found\n");
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	ret = v4l2_fwnode_endpoint_parse(endpoint, &sensor->ep);
> > > > +	fwnode_handle_put(endpoint);
> > > > +	if (ret) {
> > > > +		dev_err(dev, "Could not parse endpoint\n");
> > > > +		return ret;
> > > > +	}
> > > > +
> > > > +	/* get system clock (xclk) */
> > > > +	sensor->xclk = devm_clk_get(dev, "xvclk");
> > > 
> > > This driver seems to be based on register lists. Which xvclk frequency are
> > > they for?
> > 
> > I am afraid i don't understand this one.
> 
> The sensor has a PLL for generating higher clock frequencies than the
> external clock input signal. The PLL has limits within it may operate, and
> its configuration set in registers as well as the external clock frequency
> need to be consistent in such a way these limits are not breached.
> 
> Also see
> <URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>.
> 
> > 
> > > > +	if (IS_ERR(sensor->xclk)) {
> > > > +		dev_err(dev, "failed to get xvclk\n");
> > > > +		return PTR_ERR(sensor->xclk);
> > > > +	}
> > > > +
> > > > +	sensor->xclk_freq = clk_get_rate(sensor->xclk);
> > > > +	if (sensor->xclk_freq < OVM6211_XVCLK_MIN ||
> > > > +	    sensor->xclk_freq > OVM6211_XVCLK_MAX) {
> > > > +		dev_err(dev, "xvclk frequency out of range: %d Hz\n",
> > > > +			sensor->xclk_freq);
> > > > +		return -EINVAL;
> > > > +	}
> > > > +
> > > > +	/* request optional power down pin */
> > > > +	sensor->pwdn_gpio = devm_gpiod_get_optional(dev, "powerdown",
> > > > +						    GPIOD_OUT_HIGH);
> > > > +	if (IS_ERR(sensor->pwdn_gpio))
> > > > +		return PTR_ERR(sensor->pwdn_gpio);
> > > > +
> > > > +	/* request optional reset pin */
> > > > +	sensor->reset_gpio = devm_gpiod_get_optional(dev, "reset",
> > > > +						     GPIOD_OUT_HIGH);
> > > > +	if (IS_ERR(sensor->reset_gpio))
> > > > +		return PTR_ERR(sensor->reset_gpio);
> > > > +
> > > > +	sensor->regmap = devm_regmap_init_i2c(client, &ovm6211_regmap_config);
> > > > +	if (IS_ERR(sensor->regmap)) {
> > > > +		dev_err(dev, "regmap init failed\n");
> > > > +		return PTR_ERR(sensor->regmap);
> > > > +	}
> > > > +
> > > > +	v4l2_i2c_subdev_init(&sensor->sd, client, &ovm6211_subdev_ops);
> > > > +
> > > > +	sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
> > > > +			    V4L2_SUBDEV_FL_HAS_EVENTS;
> > > > +	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > > +	sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > > > +	ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
> > > > +	if (ret)
> > > > +		return ret;
> > > 
> > > You'll need to call media_entity_cleanup() after this.
> > 
> > Ahem, didn't know that.  Is it documented somewhere so i can read up on this?
> 
> See include/media/media-entity.h .
> 
> The function currently does nothing and we might remove it in the future. But
> for now, please do use it.

Done.

> > > > +
> > > > +	ret = ovm6211_get_regulators(sensor);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	ret = ovm6211_set_power(&sensor->sd, 1);
> > > > +	if (ret)
> > > > +		return ret;
> > > > +
> > > > +	mutex_init(&sensor->lock);
> > > > +
> > > > +	ret = ovm6211_check_chip_id(sensor);
> > > > +	if (ret)
> > > > +		goto entity_cleanup;
> > > > +
> > > > +	ret = ovm6211_init_controls(sensor);
> > > > +	if (ret)
> > > > +		goto entity_cleanup;
> > > > +
> > > > +	ret = v4l2_async_register_subdev_sensor(&sensor->sd);
> 
> Note that the sensor could be already be used by user space at this point.
> All initialisation needs thus to precede registering the async subdev.

Right, done.

> > > > +	if (ret)
> > > > +		goto free_ctrls;
> > > > +
> > > > +	ovm6211_load_regs(sensor, ovm6211_mode_init_data);
> > > 
> > > Please add support for runtime PM.
> > > 
> > > I'd suggest to take a look at this as well:
> > > 
> > > <URL:https://hverkuil.home.xs4all.nl/spec/driver-api/camera-sensor.html>
> > > 
> > > > +
> > > > +	dev_dbg(dev, "%s() completed\n", __func__);
> > > 
> > > Please remove.
> > 
> > OK.
> > 
> > > > +	return 0;
> > > > +
> > > > +free_ctrls:
> > > > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > > > +entity_cleanup:
> > > > +	media_entity_cleanup(&sensor->sd.entity);
> > > > +	mutex_destroy(&sensor->lock);
> > > > +	return ret;
> > > > +}
> > > > +
> > > > +static int ovm6211_remove(struct i2c_client *client)
> > > > +{
> > > > +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > > > +	struct ovm6211_dev *sensor = to_ovm6211_dev(sd);
> > > > +
> > > > +	v4l2_async_unregister_subdev(&sensor->sd);
> > > > +	media_entity_cleanup(&sensor->sd.entity);
> > > > +	v4l2_ctrl_handler_free(&sensor->ctrls.handler);
> > > > +	mutex_destroy(&sensor->lock);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static const struct i2c_device_id ovm6211_id[] = {
> > > > +	{ "ovm6211", 0 },
> > > > +	{},
> > > > +};
> > > > +MODULE_DEVICE_TABLE(i2c, ovm6211_id);
> > > > +
> > > > +static const struct of_device_id ovm6211_dt_ids[] = {
> > > > +	{ .compatible = "ovti,ovm6211" },
> > > > +	{ /* sentinel */ }
> > > > +};
> > > > +MODULE_DEVICE_TABLE(of, ovm6211_dt_ids);
> > > > +
> > > > +static struct i2c_driver ovm6211_i2c_driver = {
> > > > +	.driver = {
> > > > +		.name  = "ovm6211",
> > > > +		.of_match_table	= ovm6211_dt_ids,
> > > > +	},
> > > > +	.id_table = ovm6211_id,
> > > 
> > > Please remove ovm62211_id table unless you really need it.
> > 
> > OK.
> > 
> > > > +	.probe_new = ovm6211_probe,
> > > > +	.remove   = ovm6211_remove,
> > > > +};
> > > > +
> > > > +module_i2c_driver(ovm6211_i2c_driver);
> > > > +
> > > > +MODULE_AUTHOR("Petko Manolov <petko.manolov@konsulko.com>");
> > > > +MODULE_DESCRIPTION("OVM6211 MIPI Camera Subdev Driver");
> > > > +MODULE_LICENSE("GPL");
> > > 
> > > -- 
> > > Kind regards,
> > > 
> > > Sakari Ailus
> > 
> > Thanks for the detailed review, Sakari, much appreciated.
> 
> You're welcome!

As usual, thank you.


		Petko

[RFC PATCH 2/5] adds ovm6211 entry to Kconfig

[Petko Manolov]

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
---
 drivers/staging/media/i2c/Kconfig | 9 +++++++++
 1 file changed, 9 insertions(+)
 create mode 100644 drivers/staging/media/i2c/Kconfig

diff --git a/drivers/staging/media/i2c/Kconfig b/drivers/staging/media/i2c/Kconfig
new file mode 100644
index 000000000000..2744f654121a
--- /dev/null
+++ b/drivers/staging/media/i2c/Kconfig
@@ -0,0 +1,9 @@
+config VIDEO_OVM6211
+	tristate "OmniVision OVM6211 sensor support"
+	depends on I2C && VIDEO_V4L2
+	help
+	  This is a Video4Linux2 sensor driver for the OmniVision
+	  OVM6211 camera.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ovm6211.
-- 
2.30.2

[RFC PATCH 3/5] adds ovm6211 entry to Makefile

[Petko Manolov]

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
---
 drivers/staging/media/i2c/Makefile | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 drivers/staging/media/i2c/Makefile

diff --git a/drivers/staging/media/i2c/Makefile b/drivers/staging/media/i2c/Makefile
new file mode 100644
index 000000000000..4d6f2956b3f1
--- /dev/null
+++ b/drivers/staging/media/i2c/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_VIDEO_OVM6211) += ovm6211.o
-- 
2.30.2

[RFC PATCH 4/5] adds drivers/staging/media/i2c/Kconfig entry

[Petko Manolov]

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
---
 drivers/staging/media/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/staging/media/Kconfig b/drivers/staging/media/Kconfig
index e3aaae920847..c034004bda60 100644
--- a/drivers/staging/media/Kconfig
+++ b/drivers/staging/media/Kconfig
@@ -24,6 +24,8 @@ source "drivers/staging/media/atomisp/Kconfig"
 
 source "drivers/staging/media/hantro/Kconfig"
 
+source "drivers/staging/media/i2c/Kconfig"
+
 source "drivers/staging/media/imx/Kconfig"
 
 source "drivers/staging/media/meson/vdec/Kconfig"
-- 
2.30.2

[RFC PATCH 5/5] adds i2c/ explicitly to Makefile

[Petko Manolov]

Signed-off-by: Petko Manolov <petko.manolov@konsulko.com>
---
 drivers/staging/media/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/staging/media/Makefile b/drivers/staging/media/Makefile
index 5b5afc5b03a0..e2b34361ec37 100644
--- a/drivers/staging/media/Makefile
+++ b/drivers/staging/media/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_VIDEO_HANTRO)	+= hantro/
 obj-$(CONFIG_VIDEO_IPU3_IMGU)	+= ipu3/
 obj-$(CONFIG_VIDEO_ZORAN)	+= zoran/
 obj-$(CONFIG_DVB_AV7110)	+= av7110/
+obj-y				+= i2c/
-- 
2.30.2

Re: [RFC PATCH 5/5] adds i2c/ explicitly to Makefile

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 2964 bytes --]

Hi Petko,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on v5.16-rc3]
[also build test WARNING on next-20211203]
[cannot apply to media-tree/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
base:    d58071a8a76d779eedab38033ae4c821c30295a5
config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20211204/202112040918.4eYGwkXT-lkp(a)intel.com/config)
compiler: arceb-elf-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
        git checkout e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash drivers/staging/media/i2c/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/staging/media/i2c/ovm6211.c:652:5: warning: no previous prototype for 'ovm6211_set_pix_clk' [-Wmissing-prototypes]
     652 | u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
         |     ^~~~~~~~~~~~~~~~~~~


vim +/ovm6211_set_pix_clk +652 drivers/staging/media/i2c/ovm6211.c

a3407db075daa0 Petko Manolov 2021-12-04  651  
a3407db075daa0 Petko Manolov 2021-12-04 @652  u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
a3407db075daa0 Petko Manolov 2021-12-04  653  {
a3407db075daa0 Petko Manolov 2021-12-04  654  	u32 s, fmt, fps, ret;
a3407db075daa0 Petko Manolov 2021-12-04  655  
a3407db075daa0 Petko Manolov 2021-12-04  656  	/* x * y * [1|2] * y8/y10 * fps */
a3407db075daa0 Petko Manolov 2021-12-04  657  	s = nm->width * nm->height;
a3407db075daa0 Petko Manolov 2021-12-04  658  	fmt = 1;
a3407db075daa0 Petko Manolov 2021-12-04  659  	fps = ovm6211_framerates[sensor->cur_fr_id];
a3407db075daa0 Petko Manolov 2021-12-04  660  	ret = s * fmt * fps * 2;
a3407db075daa0 Petko Manolov 2021-12-04  661  
a3407db075daa0 Petko Manolov 2021-12-04  662  	return ret;
a3407db075daa0 Petko Manolov 2021-12-04  663  }
a3407db075daa0 Petko Manolov 2021-12-04  664  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

Re: [RFC PATCH 5/5] adds i2c/ explicitly to Makefile

[kernel test robot]

Hi Petko,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on v5.16-rc3]
[also build test WARNING on next-20211206]
[cannot apply to media-tree/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
base:    d58071a8a76d779eedab38033ae4c821c30295a5
config: arm64-randconfig-r032-20211204 (https://download.01.org/0day-ci/archive/20211207/202112070634.8UMBEkLw-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 5f1d1854eb1450d352663ee732235893c5782237)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
        git checkout e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/staging/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/staging/media/i2c/ovm6211.c:652:5: warning: no previous prototype for function 'ovm6211_set_pix_clk' [-Wmissing-prototypes]
   u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
       ^
   drivers/staging/media/i2c/ovm6211.c:652:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
   ^
   static 
   1 warning generated.


vim +/ovm6211_set_pix_clk +652 drivers/staging/media/i2c/ovm6211.c

a3407db075daa0 Petko Manolov 2021-12-04  651  
a3407db075daa0 Petko Manolov 2021-12-04 @652  u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
a3407db075daa0 Petko Manolov 2021-12-04  653  {
a3407db075daa0 Petko Manolov 2021-12-04  654  	u32 s, fmt, fps, ret;
a3407db075daa0 Petko Manolov 2021-12-04  655  
a3407db075daa0 Petko Manolov 2021-12-04  656  	/* x * y * [1|2] * y8/y10 * fps */
a3407db075daa0 Petko Manolov 2021-12-04  657  	s = nm->width * nm->height;
a3407db075daa0 Petko Manolov 2021-12-04  658  	fmt = 1;
a3407db075daa0 Petko Manolov 2021-12-04  659  	fps = ovm6211_framerates[sensor->cur_fr_id];
a3407db075daa0 Petko Manolov 2021-12-04  660  	ret = s * fmt * fps * 2;
a3407db075daa0 Petko Manolov 2021-12-04  661  
a3407db075daa0 Petko Manolov 2021-12-04  662  	return ret;
a3407db075daa0 Petko Manolov 2021-12-04  663  }
a3407db075daa0 Petko Manolov 2021-12-04  664  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

Re: [RFC PATCH 5/5] adds i2c/ explicitly to Makefile

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 3415 bytes --]

Hi Petko,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on v5.16-rc3]
[also build test WARNING on next-20211206]
[cannot apply to media-tree/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
base:    d58071a8a76d779eedab38033ae4c821c30295a5
config: arm64-randconfig-r032-20211204 (https://download.01.org/0day-ci/archive/20211207/202112070634.8UMBEkLw-lkp(a)intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 5f1d1854eb1450d352663ee732235893c5782237)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Petko-Manolov/omv6211-linux-kernel-driver/20211204-061436
        git checkout e3654b0a5fdd1f9b3488b69bf8cc1a2613788f83
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/staging/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/staging/media/i2c/ovm6211.c:652:5: warning: no previous prototype for function 'ovm6211_set_pix_clk' [-Wmissing-prototypes]
   u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
       ^
   drivers/staging/media/i2c/ovm6211.c:652:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
   ^
   static 
   1 warning generated.


vim +/ovm6211_set_pix_clk +652 drivers/staging/media/i2c/ovm6211.c

a3407db075daa0 Petko Manolov 2021-12-04  651  
a3407db075daa0 Petko Manolov 2021-12-04 @652  u32 ovm6211_set_pix_clk(struct ovm6211_dev *sensor, const struct ovm6211_mode_info *nm)
a3407db075daa0 Petko Manolov 2021-12-04  653  {
a3407db075daa0 Petko Manolov 2021-12-04  654  	u32 s, fmt, fps, ret;
a3407db075daa0 Petko Manolov 2021-12-04  655  
a3407db075daa0 Petko Manolov 2021-12-04  656  	/* x * y * [1|2] * y8/y10 * fps */
a3407db075daa0 Petko Manolov 2021-12-04  657  	s = nm->width * nm->height;
a3407db075daa0 Petko Manolov 2021-12-04  658  	fmt = 1;
a3407db075daa0 Petko Manolov 2021-12-04  659  	fps = ovm6211_framerates[sensor->cur_fr_id];
a3407db075daa0 Petko Manolov 2021-12-04  660  	ret = s * fmt * fps * 2;
a3407db075daa0 Petko Manolov 2021-12-04  661  
a3407db075daa0 Petko Manolov 2021-12-04  662  	return ret;
a3407db075daa0 Petko Manolov 2021-12-04  663  }
a3407db075daa0 Petko Manolov 2021-12-04  664  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org