[PATCH v3] Documentation: leds: Add description of v4l2-flash sub-device

[PATCH v3] Documentation: leds: Add description of v4l2-flash sub-device

[Jacek Anaszewski]

This patch extends LED Flash class documention by
the description of interactions with v4l2-flash sub-device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
---
 Documentation/leds/leds-class-flash.txt |   46 +++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

- extended description of v4l2_flash API

diff --git a/Documentation/leds/leds-class-flash.txt b/Documentation/leds/leds-class-flash.txt
index 19bb673..9d45667 100644
--- a/Documentation/leds/leds-class-flash.txt
+++ b/Documentation/leds/leds-class-flash.txt
@@ -20,3 +20,49 @@ Following sysfs attributes are exposed for controlling flash LED devices:
 	- max_flash_timeout
 	- flash_strobe
 	- flash_fault
+
+
+V4L2 Flash wrapper for flash LEDs
+=================================
+
+A LED subsystem driver can be controlled also from the level of VideoForLinux2
+subsystem. In order to enable this CONFIG_V4L2_FLASH_LED_CLASS symbol has to
+be defined in the kernel config.
+
+The driver must call the v4l2_flash_init function to get registered in the
+V4L2 subsystem. The function takes three arguments:
+- fled_cdev : the LED Flash class device to wrap
+- ops : V4L2 specific ops
+	* external_strobe_set - defines the source of the flash LED strobe -
+		V4L2_CID_FLASH_STROBE control or external source, typically
+		a sensor, which makes it possible to synchronise the flash
+		strobe start with exposure start,
+	* intensity_to_led_brightness and led_brightness_to_intensity - perform
+		enum led_brightness <-> V4L2 intensity conversion in a device
+		specific manner - they can be used for devices with non-linear
+		LED current scale.
+- config : configuration for V4L2 Flash sub-device
+	* dev_name - the name of the media entity, unique in the system,
+	* flash_faults - bitmask of flash faults that the LED Flash class
+		device can report; corresponding LED_FAULT* bit definitions are
+		available in <linux/led-class-flash.h>,
+	* intensity - constraints for the LED in the TORCH or INDICATOR mode,
+		in microamperes,
+	* has_external_strobe - external strobe capability,
+	* indicator_led - signifies that a led is of indicator type, which
+		implies that it can have only two V4L2 controls:
+		V4L2_CID_FLASH_INDICATOR_INTENSITY and V4L2_CID_FLASH_FAULT.
+
+On remove the v4l2_flash_release function has to be called, which takes one
+argument - struct v4l2_flash pointer returned previously by v4l2_flash_init.
+
+Please refer to the drivers/leds/leds-max77693.c for an exemplary usage of the
+v4l2-flash API.
+
+Once the V4L2 sub-device is registered by the driver which created the Media
+controller device, the sub-device node acts just as a node of a native V4L2
+flash API device would. The calls are simply routed to the LED flash API.
+
+Opening the V4L2 Flash sub-device makes the LED subsystem sysfs interface
+unavailable. The interface is re-enabled after the V4L2 Flash sub-device
+is closed.
-- 
1.7.9.5

[PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Jacek Anaszewski]

This patch adds device tree binding documentation for
the flash cell of the Maxim max77693 multifunctional device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: devicetree@vger.kernel.org
---
 Documentation/devicetree/bindings/mfd/max77693.txt |   63 ++++++++++++++++++++
 1 file changed, 63 insertions(+)

- added range to maxim,boost-mvout and maxim,mvsys-min description

diff --git a/Documentation/devicetree/bindings/mfd/max77693.txt b/Documentation/devicetree/bindings/mfd/max77693.txt
index 38e6440..3d2103a 100644
--- a/Documentation/devicetree/bindings/mfd/max77693.txt
+++ b/Documentation/devicetree/bindings/mfd/max77693.txt
@@ -76,7 +76,55 @@ Optional properties:
     Valid values: 4300000, 4700000, 4800000, 4900000
     Default: 4300000
 
+- led : the LED submodule device node
+
+There are two LED outputs available - FLED1 and FLED2. Each of them can
+control a separate LED or they can be connected together to double
+the maximum current for a single connected LED. One LED is represented
+by one child node.
+
+Required properties:
+- compatible : Must be "maxim,max77693-led".
+
+Optional properties:
+- maxim,trigger-type : Flash trigger type.
+	Possible trigger types:
+		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
+			the flash,
+		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
+			of the flash.
+- maxim,boost-mode :
+	In boost mode the device can produce up to 1.2A of total current
+	on both outputs. The maximum current on each output is reduced
+	to 625mA then. If not enabled explicitly, boost setting defaults to
+	LEDS_BOOST_FIXED in case both current sources are used.
+	Possible values:
+		LEDS_BOOST_OFF (0) - no boost,
+		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,
+		LEDS_BOOST_FIXED (2) - fixed mode.
+- maxim,boost-mvout : Output voltage of the boost module in millivolts.
+		Range: 3300 - 5500
+- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired
+	if chip estimates that system voltage could drop below this level due
+	to flash power consumption.
+		Range: 2400 - 3400
+
+Required properties of the LED child node:
+- led-sources : see Documentation/devicetree/bindings/leds/common.txt;
+		device current output identifiers: 0 - FLED1, 1 - FLED2
+
+Optional properties of the LED child node:
+- label : see Documentation/devicetree/bindings/leds/common.txt
+- max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+		Range: 15625 - 250000
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+		Range: 15625 - 1000000
+- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+		Range: 62500 - 1000000
+
 Example:
+#include <dt-bindings/leds/common.h>
+
 	max77693@66 {
 		compatible = "maxim,max77693";
 		reg = <0x66>;
@@ -117,5 +165,20 @@ Example:
 			maxim,thermal-regulation-celsius = <75>;
 			maxim,battery-overcurrent-microamp = <3000000>;
 			maxim,charge-input-threshold-microvolt = <4300000>;
+
+		led {
+			compatible = "maxim,max77693-led";
+			maxim,trigger-type = <LEDS_TRIG_TYPE_LEVEL>;
+			maxim,boost-mode = <LEDS_BOOST_FIXED>;
+			maxim,boost-mvout = <5000>;
+			maxim,mvsys-min = <2400>;
+
+			camera_flash: flash-led {
+				label = "max77693-flash";
+				led-sources = <0>, <1>;
+				max-microamp = <500000>;
+				flash-max-microamp = <1250000>;
+				flash-timeout-us = <1000000>;
+			};
 		};
 	};
-- 
1.7.9.5

[PATCH v3] leds: Add support for max77693 mfd flash cell

[Jacek Anaszewski]

This patch adds led-flash support to Maxim max77693 chipset.
A device can be exposed to user space through LED subsystem
sysfs interface. Device supports up to two leds which can
work in flash and torch mode. The leds can be triggered
externally or by software.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/leds/Kconfig         |   10 +
 drivers/leds/Makefile        |    1 +
 drivers/leds/leds-max77693.c |  972 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 983 insertions(+)
 create mode 100644 drivers/leds/leds-max77693.c

- removed not needed '#include <asm/div64.h>' directive

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 966b960..f9fbeb5 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -467,6 +467,16 @@ config LEDS_TCA6507
 	  LED driver chips accessed via the I2C bus.
 	  Driver support brightness control and hardware-assisted blinking.
 
+config LEDS_MAX77693
+	tristate "LED support for MAX77693 Flash"
+	depends on LEDS_CLASS_FLASH
+	depends on MFD_MAX77693
+	depends on OF
+	help
+	  This option enables support for the flash part of the MAX77693
+	  multifunction device. It has build in control for two leds in flash
+	  and torch mode.
+
 config LEDS_MAX8997
 	tristate "LED support for MAX8997 PMIC"
 	depends on LEDS_CLASS && MFD_MAX8997
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index bf46093..9413fdb 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_LEDS_MC13783)		+= leds-mc13783.o
 obj-$(CONFIG_LEDS_NS2)			+= leds-ns2.o
 obj-$(CONFIG_LEDS_NETXBIG)		+= leds-netxbig.o
 obj-$(CONFIG_LEDS_ASIC3)		+= leds-asic3.o
+obj-$(CONFIG_LEDS_MAX77693)		+= leds-max77693.o
 obj-$(CONFIG_LEDS_MAX8997)		+= leds-max8997.o
 obj-$(CONFIG_LEDS_LM355x)		+= leds-lm355x.o
 obj-$(CONFIG_LEDS_BLINKM)		+= leds-blinkm.o
diff --git a/drivers/leds/leds-max77693.c b/drivers/leds/leds-max77693.c
new file mode 100644
index 0000000..7453e6b
--- /dev/null
+++ b/drivers/leds/leds-max77693.c
@@ -0,0 +1,972 @@
+/*
+ * LED Flash class driver for the flash cell of max77693 mfd.
+ *
+ *	Copyright (C) 2015, Samsung Electronics Co., Ltd.
+ *
+ *	Authors: Jacek Anaszewski <j.anaszewski@samsung.com>
+ *		 Andrzej Hajda <a.hajda@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/led-class-flash.h>
+#include <linux/mfd/max77693.h>
+#include <linux/mfd/max77693-private.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <uapi/linux/leds.h>
+
+#define MODE_OFF		0
+#define MODE_FLASH(a)		(1 << (a))
+#define MODE_TORCH(a)		(1 << (2 + (a)))
+#define MODE_FLASH_EXTERNAL(a)	(1 << (4 + (a)))
+
+#define MODE_FLASH_MASK		(MODE_FLASH(FLED1) | MODE_FLASH(FLED2) | \
+				 MODE_FLASH_EXTERNAL(FLED1) | \
+				 MODE_FLASH_EXTERNAL(FLED2))
+#define MODE_TORCH_MASK		(MODE_TORCH(FLED1) | MODE_TORCH(FLED2))
+
+#define FLED1_IOUT		(1 << 0)
+#define FLED2_IOUT		(1 << 1)
+
+enum max77693_fled {
+	FLED1,
+	FLED2,
+};
+
+enum max77693_led_mode {
+	FLASH,
+	TORCH,
+};
+
+struct max77693_led_config_data {
+	const char *label[2];
+	u32 iout_torch_max[2];
+	u32 iout_flash_max[2];
+	u32 flash_timeout[2];
+	u32 num_leds;
+	u32 boost_mode;
+	u32 boost_vout;
+	u32 low_vsys;
+	u32 trigger_type;
+};
+
+struct max77693_sub_led {
+	/* corresponding FLED output identifier */
+	int fled_id;
+	/* corresponding LED Flash class device */
+	struct led_classdev_flash fled_cdev;
+	/* assures led-triggers compatibility */
+	struct work_struct work_brightness_set;
+
+	/* brightness cache */
+	unsigned int torch_brightness;
+	/* flash timeout cache */
+	unsigned int flash_timeout;
+	/* flash faults that may have occurred */
+	u32 flash_faults;
+};
+
+struct max77693_led_device {
+	/* parent mfd regmap */
+	struct regmap *regmap;
+	/* platform device data */
+	struct platform_device *pdev;
+	/* secures access to the device */
+	struct mutex lock;
+
+	/* sub led data */
+	struct max77693_sub_led sub_leds[2];
+
+	/* maximum torch current values for FLED outputs */
+	u32 iout_torch_max[2];
+	/* maximum flash current values for FLED outputs */
+	u32 iout_flash_max[2];
+	/* flash trigger type */
+	u32 trigger_type;
+
+	/* current flash timeout cache */
+	unsigned int current_flash_timeout;
+	/* ITORCH register cache */
+	u8 torch_iout_reg;
+	/* mode of fled outputs */
+	unsigned int mode_flags;
+	/* recently strobed fled */
+	int strobing_sub_led_id;
+	/* bitmask of FLED outputs use state (bit 0. - FLED1, bit 1. - FLED2) */
+	u8 fled_mask;
+	/* FLED modes that can be set */
+	u8 allowed_modes;
+
+	/* arrangement of current outputs */
+	bool iout_joint;
+};
+
+static u8 max77693_led_iout_to_reg(u32 ua)
+{
+	if (ua < FLASH_IOUT_MIN)
+		ua = FLASH_IOUT_MIN;
+	return (ua - FLASH_IOUT_MIN) / FLASH_IOUT_STEP;
+}
+
+static u8 max77693_flash_timeout_to_reg(u32 us)
+{
+	return (us - FLASH_TIMEOUT_MIN) / FLASH_TIMEOUT_STEP;
+}
+
+static inline struct max77693_sub_led *flcdev_to_sub_led(
+					struct led_classdev_flash *fled_cdev)
+{
+	return container_of(fled_cdev, struct max77693_sub_led, fled_cdev);
+}
+
+static inline struct max77693_led_device *sub_led_to_led(
+					struct max77693_sub_led *sub_led)
+{
+	return container_of(sub_led, struct max77693_led_device,
+				sub_leds[sub_led->fled_id]);
+}
+
+static inline u8 max77693_led_vsys_to_reg(u32 mv)
+{
+	return ((mv - MAX_FLASH1_VSYS_MIN) / MAX_FLASH1_VSYS_STEP) << 2;
+}
+
+static inline u8 max77693_led_vout_to_reg(u32 mv)
+{
+	return (mv - FLASH_VOUT_MIN) / FLASH_VOUT_STEP + FLASH_VOUT_RMIN;
+}
+
+static inline bool max77693_fled_used(struct max77693_led_device *led,
+					 int fled_id)
+{
+	u8 fled_bit = (fled_id == FLED1) ? FLED1_IOUT : FLED2_IOUT;
+
+	return led->fled_mask & fled_bit;
+}
+
+static int max77693_set_mode_reg(struct max77693_led_device *led, u8 mode)
+{
+	struct regmap *rmap = led->regmap;
+	int ret, v = 0, i;
+
+	for (i = FLED1; i <= FLED2; ++i) {
+		if (mode & MODE_TORCH(i))
+			v |= FLASH_EN_ON << TORCH_EN_SHIFT(i);
+
+		if (mode & MODE_FLASH(i)) {
+			v |= FLASH_EN_ON << FLASH_EN_SHIFT(i);
+		} else if (mode & MODE_FLASH_EXTERNAL(i)) {
+			v |= FLASH_EN_FLASH << FLASH_EN_SHIFT(i);
+			/*
+			 * Enable hw triggering also for torch mode, as some
+			 * camera sensors use torch led to fathom ambient light
+			 * conditions before strobing the flash.
+			 */
+			v |= FLASH_EN_TORCH << TORCH_EN_SHIFT(i);
+		}
+	}
+
+	/* Reset the register only prior setting flash modes */
+	if (mode & ~(MODE_TORCH(FLED1) | MODE_TORCH(FLED2))) {
+		ret = regmap_write(rmap, MAX77693_LED_REG_FLASH_EN, 0);
+		if (ret < 0)
+			return ret;
+	}
+
+	return regmap_write(rmap, MAX77693_LED_REG_FLASH_EN, v);
+}
+
+static int max77693_add_mode(struct max77693_led_device *led, u8 mode)
+{
+	int i, ret;
+
+	mode &= led->allowed_modes;
+
+	/*
+	 * Torch mode once enabled remains active until turned off. If the FLED2
+	 * output isn't to be disabled check if the torch mode to be set isn't
+	 * already activated and avoid re-setting it.
+	 */
+	if ((!(mode ^ led->mode_flags)) & MODE_TORCH(FLED2)) {
+		for (i = FLED1; i <= FLED2; ++i)
+			if ((mode & led->mode_flags & MODE_TORCH(i)))
+				return 0;
+	}
+
+	if (led->iout_joint)
+		/* Span the mode on FLED2 for joint iouts case */
+		mode |= (mode << 1);
+
+	/*
+	 * FLASH_EXTERNAL mode activates FLASHEN and TORCHEN pins in the device.
+	 * Corresponding register bit fields interfere with SW triggered modes,
+	 * thus clear them to ensure proper device configuration.
+	 */
+	for (i = FLED1; i <= FLED2; ++i)
+		if (mode & MODE_FLASH_EXTERNAL(i))
+			led->mode_flags &= (~MODE_TORCH(i) & ~MODE_FLASH(i));
+
+	led->mode_flags |= mode;
+	led->mode_flags &= led->allowed_modes;
+
+	ret = max77693_set_mode_reg(led, led->mode_flags);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Clear flash mode flag after setting the mode to avoid spurious flash
+	 * strobing on each subsequent torch mode setting.
+	 */
+	if (mode & MODE_FLASH_MASK)
+		led->mode_flags &= ~mode;
+
+	return ret;
+}
+
+static int max77693_clear_mode(struct max77693_led_device *led,
+				u8 mode)
+{
+	if (led->iout_joint)
+		/* Clear mode also on FLED2 for joint iouts case */
+		mode |= (mode << 1);
+
+	led->mode_flags &= ~mode;
+
+	return max77693_set_mode_reg(led, led->mode_flags);
+}
+
+static void max77693_add_allowed_modes(struct max77693_led_device *led,
+				int fled_id, enum max77693_led_mode mode)
+{
+	if (mode == FLASH)
+		led->allowed_modes |= (MODE_FLASH(fled_id) |
+				       MODE_FLASH_EXTERNAL(fled_id));
+	else
+		led->allowed_modes |= MODE_TORCH(fled_id);
+}
+
+static void max77693_distribute_currents(struct max77693_led_device *led,
+				int fled_id, enum max77693_led_mode mode,
+				u32 micro_amp, u32 iout_max[2], u32 iout[2])
+{
+	if (!led->iout_joint) {
+		iout[fled_id] = micro_amp;
+		max77693_add_allowed_modes(led, fled_id, mode);
+		return;
+	}
+
+	iout[FLED1] = min(micro_amp, iout_max[FLED1]);
+	iout[FLED2] = micro_amp - iout[FLED1];
+
+	if (mode == FLASH)
+		led->allowed_modes &= ~MODE_FLASH_MASK;
+	else
+		led->allowed_modes &= ~MODE_TORCH_MASK;
+
+	max77693_add_allowed_modes(led, FLED1, mode);
+
+	if (iout[FLED2])
+		max77693_add_allowed_modes(led, FLED2, mode);
+}
+
+static int max77693_set_torch_current(struct max77693_led_device *led,
+				int fled_id, u32 micro_amp)
+{
+	struct regmap *rmap = led->regmap;
+	u8 iout1_reg = 0, iout2_reg = 0;
+	u32 iout[2];
+
+	max77693_distribute_currents(led, fled_id, TORCH, micro_amp,
+					led->iout_torch_max, iout);
+
+	if (fled_id == FLED1 || led->iout_joint) {
+		iout1_reg = max77693_led_iout_to_reg(iout[FLED1]);
+		led->torch_iout_reg &= TORCH_IOUT_MASK(TORCH_IOUT2_SHIFT);
+	}
+	if (fled_id == FLED2 || led->iout_joint) {
+		iout2_reg = max77693_led_iout_to_reg(iout[FLED2]);
+		led->torch_iout_reg &= TORCH_IOUT_MASK(TORCH_IOUT1_SHIFT);
+	}
+
+	led->torch_iout_reg |= ((iout1_reg << TORCH_IOUT1_SHIFT) |
+				(iout2_reg << TORCH_IOUT2_SHIFT));
+
+	return regmap_write(rmap, MAX77693_LED_REG_ITORCH,
+						led->torch_iout_reg);
+}
+
+static int max77693_set_flash_current(struct max77693_led_device *led,
+					int fled_id,
+					u32 micro_amp)
+{
+	struct regmap *rmap = led->regmap;
+	u8 iout1_reg, iout2_reg;
+	u32 iout[2];
+	int ret = -EINVAL;
+
+	max77693_distribute_currents(led, fled_id, FLASH, micro_amp,
+					led->iout_flash_max, iout);
+
+	if (fled_id == FLED1 || led->iout_joint) {
+		iout1_reg = max77693_led_iout_to_reg(iout[FLED1]);
+		ret = regmap_write(rmap, MAX77693_LED_REG_IFLASH1,
+							iout1_reg);
+		if (ret < 0)
+			return ret;
+	}
+	if (fled_id == FLED2 || led->iout_joint) {
+		iout2_reg = max77693_led_iout_to_reg(iout[FLED2]);
+		ret = regmap_write(rmap, MAX77693_LED_REG_IFLASH2,
+							iout2_reg);
+	}
+
+	return ret;
+}
+
+static int max77693_set_timeout(struct max77693_led_device *led, u32 microsec)
+{
+	struct regmap *rmap = led->regmap;
+	u8 v;
+	int ret;
+
+	v = max77693_flash_timeout_to_reg(microsec);
+
+	if (led->trigger_type == MAX77693_LED_TRIG_TYPE_LEVEL)
+		v |= FLASH_TMR_LEVEL;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_FLASH_TIMER, v);
+	if (ret < 0)
+		return ret;
+
+	led->current_flash_timeout = microsec;
+
+	return 0;
+}
+
+static int max77693_get_strobe_status(struct max77693_led_device *led,
+					bool *state)
+{
+	struct regmap *rmap = led->regmap;
+	unsigned int v;
+	int ret;
+
+	ret = regmap_read(rmap, MAX77693_LED_REG_FLASH_STATUS, &v);
+	if (ret < 0)
+		return ret;
+
+	*state = v & FLASH_STATUS_FLASH_ON;
+
+	return ret;
+}
+
+static int max77693_get_flash_faults(struct max77693_sub_led *sub_led)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	struct regmap *rmap = led->regmap;
+	unsigned int v;
+	u8 fault_open_mask, fault_short_mask;
+	int ret;
+
+	sub_led->flash_faults = 0;
+
+	if (led->iout_joint) {
+		fault_open_mask = FLASH_INT_FLED1_OPEN | FLASH_INT_FLED2_OPEN;
+		fault_short_mask = FLASH_INT_FLED1_SHORT |
+							FLASH_INT_FLED2_SHORT;
+	} else {
+		fault_open_mask = (sub_led->fled_id == FLED1) ?
+						FLASH_INT_FLED1_OPEN :
+						FLASH_INT_FLED2_OPEN;
+		fault_short_mask = (sub_led->fled_id == FLED1) ?
+						FLASH_INT_FLED1_SHORT :
+						FLASH_INT_FLED2_SHORT;
+	}
+
+	ret = regmap_read(rmap, MAX77693_LED_REG_FLASH_INT, &v);
+	if (ret < 0)
+		return ret;
+
+	if (v & fault_open_mask)
+		sub_led->flash_faults |= LED_FAULT_OVER_VOLTAGE;
+	if (v & fault_short_mask)
+		sub_led->flash_faults |= LED_FAULT_SHORT_CIRCUIT;
+	if (v & FLASH_INT_OVER_CURRENT)
+		sub_led->flash_faults |= LED_FAULT_OVER_CURRENT;
+
+	return 0;
+}
+
+static int max77693_setup(struct max77693_led_device *led,
+			 struct max77693_led_config_data *led_cfg)
+{
+	struct regmap *rmap = led->regmap;
+	int i, first_led, last_led, ret;
+	u32 max_flash_curr[2];
+	u8 v;
+
+	/*
+	 * Initialize only flash current. Torch current doesn't
+	 * require initialization as ITORCH register is written with
+	 * new value each time brightness_set op is called.
+	 */
+	if (led->iout_joint) {
+		first_led = FLED1;
+		last_led = FLED1;
+		max_flash_curr[FLED1] = led_cfg->iout_flash_max[FLED1] +
+					led_cfg->iout_flash_max[FLED2];
+	} else {
+		first_led = max77693_fled_used(led, FLED1) ? FLED1 : FLED2;
+		last_led = max77693_fled_used(led, FLED2) ? FLED2 : FLED1;
+		max_flash_curr[FLED1] = led_cfg->iout_flash_max[FLED1];
+		max_flash_curr[FLED2] = led_cfg->iout_flash_max[FLED2];
+	}
+
+	for (i = first_led; i <= last_led; ++i) {
+		ret = max77693_set_flash_current(led, i,
+					max_flash_curr[i]);
+		if (ret < 0)
+			return ret;
+	}
+
+	v = TORCH_TMR_NO_TIMER | MAX77693_LED_TRIG_TYPE_LEVEL;
+	ret = regmap_write(rmap, MAX77693_LED_REG_ITORCHTIMER, v);
+	if (ret < 0)
+		return ret;
+
+	if (led_cfg->low_vsys > 0)
+		v = max77693_led_vsys_to_reg(led_cfg->low_vsys) |
+						MAX_FLASH1_MAX_FL_EN;
+	else
+		v = 0;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_MAX_FLASH1, v);
+	if (ret < 0)
+		return ret;
+	ret = regmap_write(rmap, MAX77693_LED_REG_MAX_FLASH2, 0);
+	if (ret < 0)
+		return ret;
+
+	if (led_cfg->boost_mode == MAX77693_LED_BOOST_FIXED)
+		v = FLASH_BOOST_FIXED;
+	else
+		v = led_cfg->boost_mode | led_cfg->boost_mode << 1;
+
+	if (max77693_fled_used(led, FLED1) && max77693_fled_used(led, FLED2))
+		v |= FLASH_BOOST_LEDNUM_2;
+
+	ret = regmap_write(rmap, MAX77693_LED_REG_VOUT_CNTL, v);
+	if (ret < 0)
+		return ret;
+
+	v = max77693_led_vout_to_reg(led_cfg->boost_vout);
+	ret = regmap_write(rmap, MAX77693_LED_REG_VOUT_FLASH1, v);
+	if (ret < 0)
+		return ret;
+
+	return max77693_set_mode_reg(led, MODE_OFF);
+}
+
+static int __max77693_led_brightness_set(struct max77693_led_device *led,
+					int fled_id, enum led_brightness value)
+{
+	int ret;
+
+	mutex_lock(&led->lock);
+
+	if (value == 0) {
+		ret = max77693_clear_mode(led, MODE_TORCH(fled_id));
+		if (ret < 0)
+			dev_dbg(&led->pdev->dev,
+				"Failed to clear torch mode (%d)\n",
+				ret);
+		goto unlock;
+	}
+
+	ret = max77693_set_torch_current(led, fled_id, value * TORCH_IOUT_STEP);
+	if (ret < 0) {
+		dev_dbg(&led->pdev->dev,
+			"Failed to set torch current (%d)\n",
+			ret);
+		goto unlock;
+	}
+
+	ret = max77693_add_mode(led, MODE_TORCH(fled_id));
+	if (ret < 0)
+		dev_dbg(&led->pdev->dev,
+			"Failed to set torch mode (%d)\n",
+			ret);
+unlock:
+	mutex_unlock(&led->lock);
+	return ret;
+}
+
+static void max77693_led_brightness_set_work(
+					struct work_struct *work)
+{
+	struct max77693_sub_led *sub_led =
+			container_of(work, struct max77693_sub_led,
+					work_brightness_set);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	__max77693_led_brightness_set(led, sub_led->fled_id,
+				sub_led->torch_brightness);
+}
+
+/* LED subsystem callbacks */
+
+static int max77693_led_brightness_set_sync(
+				struct led_classdev *led_cdev,
+				enum led_brightness value)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	return __max77693_led_brightness_set(led, sub_led->fled_id, value);
+}
+
+static void max77693_led_brightness_set(
+				struct led_classdev *led_cdev,
+				enum led_brightness value)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+
+	sub_led->torch_brightness = value;
+	schedule_work(&sub_led->work_brightness_set);
+}
+
+static int max77693_led_flash_brightness_set(
+				struct led_classdev_flash *fled_cdev,
+				u32 brightness)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int ret;
+
+	mutex_lock(&led->lock);
+	ret = max77693_set_flash_current(led, sub_led->fled_id, brightness);
+	mutex_unlock(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_flash_strobe_set(
+				struct led_classdev_flash *fled_cdev,
+				bool state)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	int ret;
+
+	mutex_lock(&led->lock);
+
+	if (!state) {
+		ret = max77693_clear_mode(led, MODE_FLASH(fled_id));
+		goto unlock;
+	}
+
+	if (sub_led->flash_timeout != led->current_flash_timeout) {
+		ret = max77693_set_timeout(led, sub_led->flash_timeout);
+		if (ret < 0)
+			goto unlock;
+	}
+
+	led->strobing_sub_led_id = fled_id;
+
+	ret = max77693_add_mode(led, MODE_FLASH(fled_id));
+	if (ret < 0)
+		goto unlock;
+
+	ret = max77693_get_flash_faults(sub_led);
+
+unlock:
+	mutex_unlock(&led->lock);
+	return ret;
+}
+
+static int max77693_led_flash_fault_get(
+				struct led_classdev_flash *fled_cdev,
+				u32 *fault)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+
+	*fault = sub_led->flash_faults;
+
+	return 0;
+}
+
+static int max77693_led_flash_strobe_get(
+				struct led_classdev_flash *fled_cdev,
+				bool *state)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int ret;
+
+	if (!state)
+		return -EINVAL;
+
+	mutex_lock(&led->lock);
+
+	ret = max77693_get_strobe_status(led, state);
+
+	*state = !!(*state && (led->strobing_sub_led_id == sub_led->fled_id));
+
+	mutex_unlock(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_flash_timeout_set(
+				struct led_classdev_flash *fled_cdev,
+				u32 timeout)
+{
+	struct max77693_sub_led *sub_led = flcdev_to_sub_led(fled_cdev);
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+
+	mutex_lock(&led->lock);
+	sub_led->flash_timeout = timeout;
+	mutex_unlock(&led->lock);
+
+	return 0;
+}
+
+static int max77693_led_parse_dt(struct max77693_led_device *led,
+				struct max77693_led_config_data *cfg)
+{
+	struct device *dev = &led->pdev->dev;
+	struct max77693_sub_led *sub_leds = led->sub_leds;
+	struct device_node *node = dev->of_node, *child_node;
+	struct property *prop;
+	u32 led_sources[2];
+	int i, fled_id;
+
+	of_property_read_u32(node, "maxim,trigger-type", &cfg->trigger_type);
+	of_property_read_u32(node, "maxim,boost-mode", &cfg->boost_mode);
+	of_property_read_u32(node, "maxim,boost-mvout", &cfg->boost_vout);
+	of_property_read_u32(node, "maxim,mvsys-min", &cfg->low_vsys);
+
+	for_each_available_child_of_node(node, child_node) {
+		prop = of_find_property(child_node, "led-sources", NULL);
+		if (prop) {
+			const __be32 *srcs = NULL;
+
+			for (i = 0; i < ARRAY_SIZE(led_sources); ++i) {
+				srcs = of_prop_next_u32(prop, srcs,
+							&led_sources[i]);
+				if (!srcs)
+					break;
+			}
+		} else {
+			dev_err(dev,
+				"\"led-sources\" DT property not found.\n");
+			return -EINVAL;
+		}
+
+		if (i == 2) {
+			fled_id = FLED1;
+			led->fled_mask = FLED1_IOUT | FLED2_IOUT;
+		} else if (led_sources[0] == FLED1) {
+			fled_id = FLED1;
+			led->fled_mask |= FLED1_IOUT;
+		} else if (led_sources[0] == FLED2) {
+			fled_id = FLED2;
+			led->fled_mask |= FLED2_IOUT;
+		} else {
+			dev_err(dev,
+				"Wrong \"led-sources\" DT property value.\n");
+			return -EINVAL;
+		}
+
+		sub_leds[fled_id].fled_id = fled_id;
+
+		cfg->label[fled_id] =
+			of_get_property(child_node, "label", NULL) ? :
+						child_node->name;
+
+		of_property_read_u32(child_node, "max-microamp",
+						&cfg->iout_torch_max[fled_id]);
+		of_property_read_u32(child_node, "flash-max-microamp",
+						&cfg->iout_flash_max[fled_id]);
+		of_property_read_u32(child_node, "flash-timeout-us",
+						&cfg->flash_timeout[fled_id]);
+
+		if (++cfg->num_leds == 2 ||
+		    (max77693_fled_used(led, FLED1) &&
+		     max77693_fled_used(led, FLED2)))
+			break;
+	}
+
+	if (cfg->num_leds == 0) {
+		dev_err(dev, "No DT child node found for connected LED(s).\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
+{
+	*v = clamp_val(*v, min, max);
+	if (step > 1)
+		*v = (*v - min) / step * step + min;
+}
+
+static void max77693_led_validate_configuration(struct max77693_led_device *led,
+					struct max77693_led_config_data *cfg)
+{
+	int i;
+
+	if (cfg->num_leds == 1 &&
+	    max77693_fled_used(led, FLED1) && max77693_fled_used(led, FLED2))
+		led->iout_joint = true;
+
+	cfg->boost_mode = clamp_val(cfg->boost_mode, MAX77693_LED_BOOST_NONE,
+			    MAX77693_LED_BOOST_FIXED);
+
+	/* Boost must be enabled if both current outputs are used */
+	if ((cfg->boost_mode == MAX77693_LED_BOOST_NONE) && led->iout_joint)
+		cfg->boost_mode = MAX77693_LED_BOOST_FIXED;
+
+	/* Split max current settings to both outputs in case of joint leds */
+	if (led->iout_joint) {
+		cfg->iout_torch_max[FLED1] /= 2;
+		cfg->iout_torch_max[FLED2] = cfg->iout_torch_max[FLED1];
+		cfg->iout_flash_max[FLED1] /= 2;
+		cfg->iout_flash_max[FLED2] = cfg->iout_flash_max[FLED1];
+	}
+
+	for (i = FLED1; i <= FLED2; ++i) {
+		if (max77693_fled_used(led, i)) {
+			clamp_align(&cfg->iout_torch_max[i], TORCH_IOUT_MIN,
+					TORCH_IOUT_MAX, TORCH_IOUT_STEP);
+			clamp_align(&cfg->iout_flash_max[i], FLASH_IOUT_MIN,
+					cfg->boost_mode ? FLASH_IOUT_MAX_2LEDS :
+							FLASH_IOUT_MAX_1LED,
+					FLASH_IOUT_STEP);
+		} else {
+			cfg->iout_torch_max[i] = cfg->iout_flash_max[i] = 0;
+		}
+	}
+
+	for (i = 0; i < ARRAY_SIZE(cfg->flash_timeout); ++i)
+		clamp_align(&cfg->flash_timeout[i], FLASH_TIMEOUT_MIN,
+				FLASH_TIMEOUT_MAX, FLASH_TIMEOUT_STEP);
+
+	cfg->trigger_type = clamp_val(cfg->trigger_type,
+					MAX77693_LED_TRIG_TYPE_EDGE,
+					MAX77693_LED_TRIG_TYPE_LEVEL);
+
+	clamp_align(&cfg->boost_vout, FLASH_VOUT_MIN, FLASH_VOUT_MAX,
+							FLASH_VOUT_STEP);
+
+	if (cfg->low_vsys)
+		clamp_align(&cfg->low_vsys, MAX_FLASH1_VSYS_MIN,
+				MAX_FLASH1_VSYS_MAX, MAX_FLASH1_VSYS_STEP);
+}
+
+static int max77693_led_get_configuration(struct max77693_led_device *led,
+				struct max77693_led_config_data *cfg)
+{
+	int ret;
+
+	ret = max77693_led_parse_dt(led, cfg);
+	if (ret < 0)
+		return ret;
+
+	max77693_led_validate_configuration(led, cfg);
+
+	memcpy(led->iout_torch_max, cfg->iout_torch_max,
+				sizeof(led->iout_torch_max));
+	memcpy(led->iout_flash_max, cfg->iout_flash_max,
+				sizeof(led->iout_flash_max));
+	led->trigger_type = cfg->trigger_type;
+
+	return 0;
+}
+
+static const struct led_flash_ops flash_ops = {
+	.flash_brightness_set	= max77693_led_flash_brightness_set,
+	.strobe_set		= max77693_led_flash_strobe_set,
+	.strobe_get		= max77693_led_flash_strobe_get,
+	.timeout_set		= max77693_led_flash_timeout_set,
+	.fault_get		= max77693_led_flash_fault_get,
+};
+
+static void max77693_init_flash_settings(struct max77693_sub_led *sub_led,
+				 struct max77693_led_config_data *led_cfg)
+{
+	struct led_classdev_flash *fled_cdev = &sub_led->fled_cdev;
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	struct led_flash_setting *setting;
+
+	/* Init flash intensity setting */
+	setting = &fled_cdev->brightness;
+	setting->min = FLASH_IOUT_MIN;
+	setting->max = led->iout_joint ?
+		led_cfg->iout_flash_max[FLED1] * 2 :
+		led_cfg->iout_flash_max[fled_id];
+	setting->step = FLASH_IOUT_STEP;
+	setting->val = setting->max;
+
+	/* Init flash timeout setting */
+	setting = &fled_cdev->timeout;
+	setting->min = FLASH_TIMEOUT_MIN;
+	setting->max = led_cfg->flash_timeout[fled_id];
+	setting->step = FLASH_TIMEOUT_STEP;
+	setting->val = setting->max;
+}
+
+static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
+				struct max77693_led_config_data *led_cfg)
+{
+	struct max77693_led_device *led = sub_led_to_led(sub_led);
+	int fled_id = sub_led->fled_id;
+	struct led_classdev_flash *fled_cdev;
+	struct led_classdev *led_cdev;
+
+	/* Initialize LED Flash class device */
+	fled_cdev = &sub_led->fled_cdev;
+	fled_cdev->ops = &flash_ops;
+	led_cdev = &fled_cdev->led_cdev;
+
+	led_cdev->name = led_cfg->label[fled_id];
+
+	led_cdev->brightness_set = max77693_led_brightness_set;
+	led_cdev->brightness_set_sync = max77693_led_brightness_set_sync;
+	led_cdev->max_brightness = (led->iout_joint ?
+					led_cfg->iout_torch_max[FLED1] * 2 :
+					led_cfg->iout_torch_max[fled_id]) /
+				   TORCH_IOUT_STEP;
+	led_cdev->flags |= LED_DEV_CAP_FLASH;
+	INIT_WORK(&sub_led->work_brightness_set,
+			max77693_led_brightness_set_work);
+
+	max77693_init_flash_settings(sub_led, led_cfg);
+
+	/* Init flash timeout cache */
+	sub_led->flash_timeout = fled_cdev->timeout.val;
+}
+
+static int max77693_led_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
+	struct max77693_led_device *led;
+	struct max77693_sub_led *sub_leds;
+	struct max77693_led_config_data led_cfg = {};
+	int init_fled_cdev[2], i, ret;
+
+	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
+	if (!led)
+		return -ENOMEM;
+
+	led->pdev = pdev;
+	led->regmap = iodev->regmap;
+	led->allowed_modes = MODE_FLASH_MASK;
+	sub_leds = led->sub_leds;
+
+	platform_set_drvdata(pdev, led);
+	ret = max77693_led_get_configuration(led, &led_cfg);
+	if (ret < 0)
+		return ret;
+
+	ret = max77693_setup(led, &led_cfg);
+	if (ret < 0)
+		return ret;
+
+	mutex_init(&led->lock);
+
+	init_fled_cdev[FLED1] =
+			led->iout_joint || max77693_fled_used(led, FLED1);
+	init_fled_cdev[FLED2] =
+			!led->iout_joint && max77693_fled_used(led, FLED2);
+
+	/* Initialize LED Flash class device(s) */
+	for (i = FLED1; i <= FLED2; ++i)
+		if (init_fled_cdev[i])
+			max77693_init_fled_cdev(&sub_leds[i], &led_cfg);
+
+
+	/* Register LED Flash class device(s) */
+	for (i = FLED1; i <= FLED2; ++i) {
+		if (!init_fled_cdev[i])
+			continue;
+
+		ret = led_classdev_flash_register(dev, &sub_leds[i].fled_cdev);
+		if (ret < 0) {
+			/*
+			 * At this moment FLED1 might have been already
+			 * registered and it needs to be released.
+			 */
+			if (i == FLED2)
+				goto err_register_led2;
+			else
+				goto err_register_led1;
+		}
+	}
+
+	return 0;
+
+err_register_led2:
+	/* It is possible than only FLED2 was to be registered */
+	if (!init_fled_cdev[FLED1])
+		goto err_register_led1;
+	led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
+err_register_led1:
+	mutex_destroy(&led->lock);
+
+	return ret;
+}
+
+static int max77693_led_remove(struct platform_device *pdev)
+{
+	struct max77693_led_device *led = platform_get_drvdata(pdev);
+	struct max77693_sub_led *sub_leds = led->sub_leds;
+
+	if (led->iout_joint || max77693_fled_used(led, FLED1)) {
+		led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
+		cancel_work_sync(&sub_leds[FLED1].work_brightness_set);
+	}
+
+	if (!led->iout_joint && max77693_fled_used(led, FLED2)) {
+		led_classdev_flash_unregister(&sub_leds[FLED2].fled_cdev);
+		cancel_work_sync(&sub_leds[FLED2].work_brightness_set);
+	}
+
+	mutex_destroy(&led->lock);
+
+	return 0;
+}
+
+static const struct of_device_id max77693_led_dt_match[] = {
+	{.compatible = "maxim,max77693-led"},
+	{},
+};
+
+static struct platform_driver max77693_led_driver = {
+	.probe		= max77693_led_probe,
+	.remove		= max77693_led_remove,
+	.driver		= {
+		.name	= "max77693-led",
+		.owner	= THIS_MODULE,
+		.of_match_table = max77693_led_dt_match,
+	},
+};
+
+module_platform_driver(max77693_led_driver);
+
+MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
+MODULE_AUTHOR("Andrzej Hajda <a.hajda@samsung.com>");
+MODULE_DESCRIPTION("Maxim MAX77693 led flash driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.9.5

Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Mark Rutland]

On Mon, Mar 30, 2015 at 10:52:28AM +0100, Jacek Anaszewski wrote:
> This patch adds device tree binding documentation for
> the flash cell of the Maxim max77693 multifunctional device.
> 
> Signed-off-by: Jacek Anaszewski <j.anaszewski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Signed-off-by: Andrzej Hajda <a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Acked-by: Kyungmin Park <kyungmin.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Acked-by: Sakari Ailus <sakari.ailus-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> Cc: Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Cc: Chanwoo Choi <cw00.choi-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> Cc: Bryan Wu <cooloney-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Richard Purdie <rpurdie-Fm38FmjxZ/leoWH0uzbU5w@public.gmane.org>
> Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> ---
>  Documentation/devicetree/bindings/mfd/max77693.txt |   63 ++++++++++++++++++++
>  1 file changed, 63 insertions(+)
> 
> - added range to maxim,boost-mvout and maxim,mvsys-min description
> 
> diff --git a/Documentation/devicetree/bindings/mfd/max77693.txt b/Documentation/devicetree/bindings/mfd/max77693.txt
> index 38e6440..3d2103a 100644
> --- a/Documentation/devicetree/bindings/mfd/max77693.txt
> +++ b/Documentation/devicetree/bindings/mfd/max77693.txt
> @@ -76,7 +76,55 @@ Optional properties:
>      Valid values: 4300000, 4700000, 4800000, 4900000
>      Default: 4300000
>  
> +- led : the LED submodule device node
> +
> +There are two LED outputs available - FLED1 and FLED2. Each of them can
> +control a separate LED or they can be connected together to double
> +the maximum current for a single connected LED. One LED is represented
> +by one child node.
> +
> +Required properties:
> +- compatible : Must be "maxim,max77693-led".
> +
> +Optional properties:
> +- maxim,trigger-type : Flash trigger type.
> +	Possible trigger types:
> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
> +			the flash,
> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
> +			of the flash.

Surely this is required? What should be assumed if this property isn't
present?

Otherwise this looks OK, but I'm not that familiar with LED/flash
bindings.

Mark.

> +- maxim,boost-mode :
> +	In boost mode the device can produce up to 1.2A of total current
> +	on both outputs. The maximum current on each output is reduced
> +	to 625mA then. If not enabled explicitly, boost setting defaults to
> +	LEDS_BOOST_FIXED in case both current sources are used.
> +	Possible values:
> +		LEDS_BOOST_OFF (0) - no boost,
> +		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,
> +		LEDS_BOOST_FIXED (2) - fixed mode.
> +- maxim,boost-mvout : Output voltage of the boost module in millivolts.
> +		Range: 3300 - 5500
> +- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired
> +	if chip estimates that system voltage could drop below this level due
> +	to flash power consumption.
> +		Range: 2400 - 3400
> +
> +Required properties of the LED child node:
> +- led-sources : see Documentation/devicetree/bindings/leds/common.txt;
> +		device current output identifiers: 0 - FLED1, 1 - FLED2
> +
> +Optional properties of the LED child node:
> +- label : see Documentation/devicetree/bindings/leds/common.txt
> +- max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +		Range: 15625 - 250000
> +- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
> +		Range: 15625 - 1000000
> +- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
> +		Range: 62500 - 1000000
> +
>  Example:
> +#include <dt-bindings/leds/common.h>
> +
>  	max77693@66 {
>  		compatible = "maxim,max77693";
>  		reg = <0x66>;
> @@ -117,5 +165,20 @@ Example:
>  			maxim,thermal-regulation-celsius = <75>;
>  			maxim,battery-overcurrent-microamp = <3000000>;
>  			maxim,charge-input-threshold-microvolt = <4300000>;
> +
> +		led {
> +			compatible = "maxim,max77693-led";
> +			maxim,trigger-type = <LEDS_TRIG_TYPE_LEVEL>;
> +			maxim,boost-mode = <LEDS_BOOST_FIXED>;
> +			maxim,boost-mvout = <5000>;
> +			maxim,mvsys-min = <2400>;
> +
> +			camera_flash: flash-led {
> +				label = "max77693-flash";
> +				led-sources = <0>, <1>;
> +				max-microamp = <500000>;
> +				flash-max-microamp = <1250000>;
> +				flash-timeout-us = <1000000>;
> +			};
>  		};
>  	};
> -- 
> 1.7.9.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
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Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Jacek Anaszewski]

On 03/30/2015 01:57 PM, Mark Rutland wrote:
> On Mon, Mar 30, 2015 at 10:52:28AM +0100, Jacek Anaszewski wrote:
>> This patch adds device tree binding documentation for
>> the flash cell of the Maxim max77693 multifunctional device.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
>> Cc: Lee Jones <lee.jones@linaro.org>
>> Cc: Chanwoo Choi <cw00.choi@samsung.com>
>> Cc: Bryan Wu <cooloney@gmail.com>
>> Cc: Richard Purdie <rpurdie@rpsys.net>
>> Cc: devicetree@vger.kernel.org
>> ---
>>   Documentation/devicetree/bindings/mfd/max77693.txt |   63 ++++++++++++++++++++
>>   1 file changed, 63 insertions(+)
>>
>> - added range to maxim,boost-mvout and maxim,mvsys-min description
>>
>> diff --git a/Documentation/devicetree/bindings/mfd/max77693.txt b/Documentation/devicetree/bindings/mfd/max77693.txt
>> index 38e6440..3d2103a 100644
>> --- a/Documentation/devicetree/bindings/mfd/max77693.txt
>> +++ b/Documentation/devicetree/bindings/mfd/max77693.txt
>> @@ -76,7 +76,55 @@ Optional properties:
>>       Valid values: 4300000, 4700000, 4800000, 4900000
>>       Default: 4300000
>>
>> +- led : the LED submodule device node
>> +
>> +There are two LED outputs available - FLED1 and FLED2. Each of them can
>> +control a separate LED or they can be connected together to double
>> +the maximum current for a single connected LED. One LED is represented
>> +by one child node.
>> +
>> +Required properties:
>> +- compatible : Must be "maxim,max77693-led".
>> +
>> +Optional properties:
>> +- maxim,trigger-type : Flash trigger type.
>> +	Possible trigger types:
>> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
>> +			the flash,
>> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
>> +			of the flash.
>
> Surely this is required? What should be assumed if this property isn't
> present?

LEDS_TRIG_TYPE_LEVEL allows for an ISP to do e.g. short flash blink
before the actual strobe - it is used for eliminating photographs with
closed eyes, or can serve for probing ambient light conditions.

With LEDS_TRIG_TYPE_EDGE flash strobe is triggered on rising edge
and lasts until programmed timeout expires.

This setting is tightly related to a camera sensor, which generates
the strobe signal. Effectively it depends on board configuration.


> Otherwise this looks OK, but I'm not that familiar with LED/flash
> bindings.
>
> Mark.
>
>> +- maxim,boost-mode :
>> +	In boost mode the device can produce up to 1.2A of total current
>> +	on both outputs. The maximum current on each output is reduced
>> +	to 625mA then. If not enabled explicitly, boost setting defaults to
>> +	LEDS_BOOST_FIXED in case both current sources are used.
>> +	Possible values:
>> +		LEDS_BOOST_OFF (0) - no boost,
>> +		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,
>> +		LEDS_BOOST_FIXED (2) - fixed mode.
>> +- maxim,boost-mvout : Output voltage of the boost module in millivolts.
>> +		Range: 3300 - 5500
>> +- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired
>> +	if chip estimates that system voltage could drop below this level due
>> +	to flash power consumption.
>> +		Range: 2400 - 3400
>> +
>> +Required properties of the LED child node:
>> +- led-sources : see Documentation/devicetree/bindings/leds/common.txt;
>> +		device current output identifiers: 0 - FLED1, 1 - FLED2
>> +
>> +Optional properties of the LED child node:
>> +- label : see Documentation/devicetree/bindings/leds/common.txt
>> +- max-microamp : see Documentation/devicetree/bindings/leds/common.txt
>> +		Range: 15625 - 250000
>> +- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
>> +		Range: 15625 - 1000000
>> +- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
>> +		Range: 62500 - 1000000
>> +
>>   Example:
>> +#include <dt-bindings/leds/common.h>
>> +
>>   	max77693@66 {
>>   		compatible = "maxim,max77693";
>>   		reg = <0x66>;
>> @@ -117,5 +165,20 @@ Example:
>>   			maxim,thermal-regulation-celsius = <75>;
>>   			maxim,battery-overcurrent-microamp = <3000000>;
>>   			maxim,charge-input-threshold-microvolt = <4300000>;
>> +
>> +		led {
>> +			compatible = "maxim,max77693-led";
>> +			maxim,trigger-type = <LEDS_TRIG_TYPE_LEVEL>;
>> +			maxim,boost-mode = <LEDS_BOOST_FIXED>;
>> +			maxim,boost-mvout = <5000>;
>> +			maxim,mvsys-min = <2400>;
>> +
>> +			camera_flash: flash-led {
>> +				label = "max77693-flash";
>> +				led-sources = <0>, <1>;
>> +				max-microamp = <500000>;
>> +				flash-max-microamp = <1250000>;
>> +				flash-timeout-us = <1000000>;
>> +			};
>>   		};
>>   	};
>> --
>> 1.7.9.5
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe devicetree" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
> --
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>


-- 
Best Regards,
Jacek Anaszewski

Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Mark Rutland]

Hi,

> >> +Optional properties:
> >> +- maxim,trigger-type : Flash trigger type.
> >> +	Possible trigger types:
> >> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
> >> +			the flash,
> >> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
> >> +			of the flash.
> >
> > Surely this is required? What should be assumed if this property isn't
> > present?
> 
> LEDS_TRIG_TYPE_LEVEL allows for an ISP to do e.g. short flash blink
> before the actual strobe - it is used for eliminating photographs with
> closed eyes, or can serve for probing ambient light conditions.
> 
> With LEDS_TRIG_TYPE_EDGE flash strobe is triggered on rising edge
> and lasts until programmed timeout expires.
> 
> This setting is tightly related to a camera sensor, which generates
> the strobe signal. Effectively it depends on board configuration.

My comment wasn't to do with the semantics of eitehr option but rather
the optionality of the property.

Surely it's vital to know what this should be, and hence this property
should be required rather than optional?

If it isn't required, what would the assumed default be?

Mark.

Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Jacek Anaszewski]

Hi Mark,

On 03/30/2015 03:20 PM, Mark Rutland wrote:
> Hi,
>
>>>> +Optional properties:
>>>> +- maxim,trigger-type : Flash trigger type.
>>>> +	Possible trigger types:
>>>> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
>>>> +			the flash,
>>>> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
>>>> +			of the flash.
>>>
>>> Surely this is required? What should be assumed if this property isn't
>>> present?
>>
>> LEDS_TRIG_TYPE_LEVEL allows for an ISP to do e.g. short flash blink
>> before the actual strobe - it is used for eliminating photographs with
>> closed eyes, or can serve for probing ambient light conditions.
>>
>> With LEDS_TRIG_TYPE_EDGE flash strobe is triggered on rising edge
>> and lasts until programmed timeout expires.
>>
>> This setting is tightly related to a camera sensor, which generates
>> the strobe signal. Effectively it depends on board configuration.
>
> My comment wasn't to do with the semantics of eitehr option but rather
> the optionality of the property.
>
> Surely it's vital to know what this should be, and hence this property
> should be required rather than optional?
>
> If it isn't required, what would the assumed default be?

Default is LEDS_TRIG_TYPE_EDGE.

-- 
Best Regards,
Jacek Anaszewski

Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[sakari.ailus]

Hi Mark and Jacek,

On Mon, Mar 30, 2015 at 02:20:03PM +0100, Mark Rutland wrote:
> Hi,
> 
> > >> +Optional properties:
> > >> +- maxim,trigger-type : Flash trigger type.
> > >> +	Possible trigger types:
> > >> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
> > >> +			the flash,
> > >> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
> > >> +			of the flash.
> > >
> > > Surely this is required? What should be assumed if this property isn't
> > > present?
> > 
> > LEDS_TRIG_TYPE_LEVEL allows for an ISP to do e.g. short flash blink
> > before the actual strobe - it is used for eliminating photographs with
> > closed eyes, or can serve for probing ambient light conditions.
> > 
> > With LEDS_TRIG_TYPE_EDGE flash strobe is triggered on rising edge
> > and lasts until programmed timeout expires.
> > 
> > This setting is tightly related to a camera sensor, which generates
> > the strobe signal. Effectively it depends on board configuration.
> 
> My comment wasn't to do with the semantics of eitehr option but rather
> the optionality of the property.
> 
> Surely it's vital to know what this should be, and hence this property
> should be required rather than optional?
> 
> If it isn't required, what would the assumed default be?

I wonder if there's a use case for edge triggering. In level trigger mode,
whichever component generates the trigger signal, determines also the strobe
time (up to the timeout). The sensor or (in the case of lack of the signal
from the sensor) the ISP has the most information on the sensor timing.

The existing as3654a driver only supports level triggering while the chip
can do edge, too.

I'd make level default and perhaps add a V4L2 control / sysfs file to change
this if needed.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi	XMPP: sailus@retiisi.org.uk

Re: [PATCH v3] DT: Add documentation for the mfd Maxim max77693

[Jacek Anaszewski]

Hi Sakari,

On 03/31/2015 11:14 AM, sakari.ailus@iki.fi wrote:
> Hi Mark and Jacek,
>
> On Mon, Mar 30, 2015 at 02:20:03PM +0100, Mark Rutland wrote:
>> Hi,
>>
>>>>> +Optional properties:
>>>>> +- maxim,trigger-type : Flash trigger type.
>>>>> +	Possible trigger types:
>>>>> +		LEDS_TRIG_TYPE_EDGE (0) - Rising edge of the signal triggers
>>>>> +			the flash,
>>>>> +		LEDS_TRIG_TYPE_LEVEL (1) - Strobe pulse length controls duration
>>>>> +			of the flash.
>>>>
>>>> Surely this is required? What should be assumed if this property isn't
>>>> present?
>>>
>>> LEDS_TRIG_TYPE_LEVEL allows for an ISP to do e.g. short flash blink
>>> before the actual strobe - it is used for eliminating photographs with
>>> closed eyes, or can serve for probing ambient light conditions.
>>>
>>> With LEDS_TRIG_TYPE_EDGE flash strobe is triggered on rising edge
>>> and lasts until programmed timeout expires.
>>>
>>> This setting is tightly related to a camera sensor, which generates
>>> the strobe signal. Effectively it depends on board configuration.
>>
>> My comment wasn't to do with the semantics of eitehr option but rather
>> the optionality of the property.
>>
>> Surely it's vital to know what this should be, and hence this property
>> should be required rather than optional?
>>
>> If it isn't required, what would the assumed default be?
>
> I wonder if there's a use case for edge triggering. In level trigger mode,
> whichever component generates the trigger signal, determines also the strobe
> time (up to the timeout). The sensor or (in the case of lack of the signal
> from the sensor) the ISP has the most information on the sensor timing.
>
> The existing as3654a driver only supports level triggering while the chip
> can do edge, too.
>
> I'd make level default and perhaps add a V4L2 control / sysfs file to change
> this if needed.

That sounds reasonable. I am going to come up with another version of
leds-max77693.c patch anyway, so I'll address this issue too.

-- 
Best Regards,
Jacek Anaszewski