[V2, 2/2] media: i2c: Add DW9768 VCM driver

dongchun.zhu
2019-09-05T07:21:42Z

From: Dongchun Zhu <dongchun.zhu@mediatek.com>

This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
and provides control to set the desired focus.

The DW9768 is a 10 bit DAC with 100mA output current sink capability
from Dongwoon, designed for linear control of voice coil motor,
and controlled via I2C serial interface.

Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
---
MAINTAINERS | 1 +
drivers/media/i2c/Kconfig | 10 ++
drivers/media/i2c/Makefile | 1 +
drivers/media/i2c/dw9768.c | 349 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 361 insertions(+)
create mode 100644 drivers/media/i2c/dw9768.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 192a671..c5c9a0e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4976,6 +4976,7 @@ M: Dongchun Zhu <dongchun.zhu@mediatek.com>
L: linux-media@vger.kernel.org
T: git git://linuxtv.org/media_tree.git
S: Maintained
+F: drivers/media/i2c/dw9768.c
F: Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.txt

DONGWOON DW9807 LENS VOICE COIL DRIVER
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 79ce9ec..dfb665c 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -1016,6 +1016,16 @@ config VIDEO_DW9714
capability. This is designed for linear control of
voice coil motors, controlled via I2C serial interface.

+config VIDEO_DW9768
+ tristate "DW9768 lens voice coil support"
+ depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
+ depends on VIDEO_V4L2_SUBDEV_API
+ help
+ This is a driver for the DW9768 camera lens voice coil.
+ DW9768 is a 10 bit DAC with 100mA output current sink
+ capability. This is designed for linear control of
+ voice coil motors, controlled via I2C serial interface.
+
config VIDEO_DW9807_VCM
tristate "DW9807 lens voice coil support"
depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index fd4ea86..2561239 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o
obj-$(CONFIG_VIDEO_AD5820) += ad5820.o
obj-$(CONFIG_VIDEO_AK7375) += ak7375.o
obj-$(CONFIG_VIDEO_DW9714) += dw9714.o
+obj-$(CONFIG_VIDEO_DW9768) += dw9768.o
obj-$(CONFIG_VIDEO_DW9807_VCM) += dw9807-vcm.o
obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
new file mode 100644
index 0000000..66d1712
--- /dev/null
+++ b/drivers/media/i2c/dw9768.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 MediaTek Inc.
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#define DW9768_NAME "dw9768"
+#define DW9768_MAX_FOCUS_POS 1023
+/*
+ * This sets the minimum granularity for the focus positions.
+ * A value of 1 gives maximum accuracy for a desired focus position
+ */
+#define DW9768_FOCUS_STEPS 1
+/*
+ * DW9768 separates two registers to control the VCM position.
+ * One for MSB value, another is LSB value.
+ */
+#define DW9768_REG_MASK_MSB 0x03
+#define DW9768_REG_MASK_LSB 0xff
+#define DW9768_SET_POSITION_ADDR 0x03
+
+#define DW9768_CMD_DELAY 0xff
+#define DW9768_CTRL_DELAY_US 5000
+
+#define DW9768_DAC_SHIFT 8
+
+/* dw9768 device structure */
+struct dw9768 {
+ struct v4l2_ctrl_handler ctrls;
+ struct v4l2_subdev sd;
+ struct regulator *vin;
+ struct regulator *vdd;
+};
+
+static inline struct dw9768 *to_dw9768_vcm(struct v4l2_ctrl *ctrl)
+{
+ return container_of(ctrl->handler, struct dw9768, ctrls);
+}
+
+static inline struct dw9768 *sd_to_dw9768_vcm(struct v4l2_subdev *subdev)
+{
+ return container_of(subdev, struct dw9768, sd);
+}
+
+struct regval_list {
+ unsigned char reg_num;
+ unsigned char value;
+};
+
+static struct regval_list dw9768_init_regs[] = {
+ {0x02, 0x02},
+ {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+ {0x06, 0x41},
+ {0x07, 0x39},
+ {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+};
+
+static struct regval_list dw9768_release_regs[] = {
+ {0x02, 0x00},
+ {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+ {0x01, 0x00},
+ {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+};
+
+static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
+ unsigned char value)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ int ret;
+
+ if (reg == DW9768_CMD_DELAY && value == DW9768_CMD_DELAY)
+ usleep_range(DW9768_CTRL_DELAY_US,
+ DW9768_CTRL_DELAY_US + 100);
+ else
+ ret = i2c_smbus_write_byte_data(client, reg, value);
+ return ret;
+}
+
+static int dw9768_write_array(struct dw9768 *dw9768, struct regval_list *vals,
+ u32 len)
+{
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < len; i++) {
+ ret = dw9768_write_smbus(dw9768, vals->reg_num, vals->value);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static int dw9768_set_position(struct dw9768 *dw9768, u16 val)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ u8 addr[2];
+
+ addr[0] = (val >> DW9768_DAC_SHIFT) & DW9768_REG_MASK_MSB;
+ addr[1] = val & DW9768_REG_MASK_LSB;
+
+ return i2c_smbus_write_block_data(client, DW9768_SET_POSITION_ADDR,
+ ARRAY_SIZE(addr), addr);
+}
+
+static int dw9768_release(struct dw9768 *dw9768)
+{
+ return dw9768_write_array(dw9768, dw9768_release_regs,
+ ARRAY_SIZE(dw9768_release_regs));
+}
+
+static int dw9768_init(struct dw9768 *dw9768)
+{
+ return dw9768_write_array(dw9768, dw9768_init_regs,
+ ARRAY_SIZE(dw9768_init_regs));
+}
+
+/* Power handling */
+static int dw9768_power_off(struct dw9768 *dw9768)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ int ret;
+
+ ret = dw9768_release(dw9768);
+ if (ret)
+ dev_err(&client->dev, "dw9768 release failed!\n");
+
+ ret = regulator_disable(dw9768->vin);
+ if (ret)
+ return ret;
+
+ return regulator_disable(dw9768->vdd);
+}
+
+static int dw9768_power_on(struct dw9768 *dw9768)
+{
+ int ret;
+
+ ret = regulator_enable(dw9768->vin);
+ if (ret < 0)
+ return ret;
+
+ ret = regulator_enable(dw9768->vdd);
+ if (ret < 0)
+ return ret;
+
+ ret = dw9768_init(dw9768);
+ if (ret < 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ regulator_disable(dw9768->vin);
+ regulator_disable(dw9768->vdd);
+
+ return ret;
+}
+
+static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+ struct dw9768 *dw9768 = to_dw9768_vcm(ctrl);
+
+ if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
+ return dw9768_set_position(dw9768, ctrl->val);
+
+ return 0;
+}
+
+static const struct v4l2_ctrl_ops dw9768_vcm_ctrl_ops = {
+ .s_ctrl = dw9768_set_ctrl,
+};
+
+static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+ int ret;
+
+ ret = pm_runtime_get_sync(sd->dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(sd->dev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+ pm_runtime_put(sd->dev);
+
+ return 0;
+}
+
+static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
+ .open = dw9768_open,
+ .close = dw9768_close,
+};
+
+static const struct v4l2_subdev_ops dw9768_ops = { };
+
+static void dw9768_subdev_cleanup(struct dw9768 *dw9768)
+{
+ v4l2_async_unregister_subdev(&dw9768->sd);
+ v4l2_ctrl_handler_free(&dw9768->ctrls);
+ media_entity_cleanup(&dw9768->sd.entity);
+}
+
+static int dw9768_init_controls(struct dw9768 *dw9768)
+{
+ struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
+ const struct v4l2_ctrl_ops *ops = &dw9768_vcm_ctrl_ops;
+
+ v4l2_ctrl_handler_init(hdl, 1);
+
+ v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
+ 0, DW9768_MAX_FOCUS_POS, DW9768_FOCUS_STEPS, 0);
+
+ if (hdl->error)
+ return hdl->error;
+
+ dw9768->sd.ctrl_handler = hdl;
+
+ return 0;
+}
+
+static int dw9768_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct dw9768 *dw9768;
+ int ret;
+
+ dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
+ if (!dw9768)
+ return -ENOMEM;
+
+ dw9768->vin = devm_regulator_get(dev, "vin");
+ if (IS_ERR(dw9768->vin)) {
+ ret = PTR_ERR(dw9768->vin);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "cannot get vin regulator\n");
+ return ret;
+ }
+
+ dw9768->vdd = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(dw9768->vdd)) {
+ ret = PTR_ERR(dw9768->vdd);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "cannot get vdd regulator\n");
+ return ret;
+ }
+
+ v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
+ dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+ dw9768->sd.internal_ops = &dw9768_int_ops;
+
+ ret = dw9768_init_controls(dw9768);
+ if (ret)
+ goto err_cleanup;
+
+ ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
+ if (ret < 0)
+ goto err_cleanup;
+
+ dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
+
+ ret = v4l2_async_register_subdev(&dw9768->sd);
+ if (ret < 0)
+ goto err_cleanup;
+
+ pm_runtime_enable(dev);
+
+ return 0;
+
+err_cleanup:
+ dw9768_subdev_cleanup(dw9768);
+ return ret;
+}
+
+static int dw9768_remove(struct i2c_client *client)
+{
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+ dw9768_subdev_cleanup(dw9768);
+ pm_runtime_disable(&client->dev);
+ if (!pm_runtime_status_suspended(&client->dev))
+ dw9768_power_off(dw9768);
+ pm_runtime_set_suspended(&client->dev);
+
+ return 0;
+}
+
+static int __maybe_unused dw9768_vcm_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+ return dw9768_power_off(dw9768);
+}
+
+static int __maybe_unused dw9768_vcm_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+ return dw9768_power_on(dw9768);
+}
+
+static const struct i2c_device_id dw9768_id_table[] = {
+ { DW9768_NAME, 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, dw9768_id_table);
+
+static const struct of_device_id dw9768_of_table[] = {
+ { .compatible = "dongwoon,dw9768" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, dw9768_of_table);
+
+static const struct dev_pm_ops dw9768_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(dw9768_vcm_suspend, dw9768_vcm_resume, NULL)
+};
+
+static struct i2c_driver dw9768_i2c_driver = {
+ .driver = {
+ .name = DW9768_NAME,
+ .pm = &dw9768_pm_ops,
+ .of_match_table = dw9768_of_table,
+ },
+ .probe_new = dw9768_probe,
+ .remove = dw9768_remove,
+ .id_table = dw9768_id_table,
+};
+
+module_i2c_driver(dw9768_i2c_driver);
+
+MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
+MODULE_DESCRIPTION("DW9768 VCM driver");
+MODULE_LICENSE("GPL v2");
--
2.9.2