Re: [PATCH 6/8] leds: as3645a: Add LED flash class driver

[Jacek Anaszewski <jacek.anaszewski@gmail.com>]

Hi Sakari,

I have two remarks in the code below.

On 06/14/2017 11:47 AM, Sakari Ailus wrote:
> From: Sakari Ailus <sakari.ailus@iki.fi>
> 
> Add a LED flash class driver for the as3654a flash controller. A V4L2 flash
> driver for it already exists (drivers/media/i2c/as3645a.c), and this driver
> is based on that.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  MAINTAINERS                 |   6 +
>  drivers/leds/Kconfig        |   8 +
>  drivers/leds/Makefile       |   1 +
>  drivers/leds/leds-as3645a.c | 744 ++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 759 insertions(+)
>  create mode 100644 drivers/leds/leds-as3645a.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 053c3bd..c7682af 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2067,6 +2067,12 @@ F:	arch/arm64/
>  F:	Documentation/arm64/
>  
>  AS3645A LED FLASH CONTROLLER DRIVER
> +M:	Sakari Ailus <sakari.ailus@iki.fi>
> +L:	linux-leds@vger.kernel.org
> +S:	Maintained
> +F:	drivers/leds/leds-as3645a.c
> +
> +AS3645A LED FLASH CONTROLLER DRIVER
>  M:	Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>  L:	linux-media@vger.kernel.org
>  T:	git git://linuxtv.org/media_tree.git
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 6c29998..9fb1d86 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -58,6 +58,14 @@ config LEDS_AAT1290
>  	help
>  	 This option enables support for the LEDs on the AAT1290.
>  
> +config LEDS_AS3645A
> +	tristate "AS3645A LED flash controller support"
> +	depends on I2C && LEDS_CLASS_FLASH
> +	help
> +	  Enable LED flash class support for AS3645A LED flash
> +	  controller. V4L2 flash API is provided as well if
> +	  CONFIG_V4L2_FLASH_API is enabled.
> +
>  config LEDS_BCM6328
>  	tristate "LED Support for Broadcom BCM6328"
>  	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 45f1339..b4def76 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_LEDS_TRIGGERS)		+= led-triggers.o
>  # LED Platform Drivers
>  obj-$(CONFIG_LEDS_88PM860X)		+= leds-88pm860x.o
>  obj-$(CONFIG_LEDS_AAT1290)		+= leds-aat1290.o
> +obj-$(CONFIG_LEDS_AS3645A)		+= leds-as3645a.o
>  obj-$(CONFIG_LEDS_BCM6328)		+= leds-bcm6328.o
>  obj-$(CONFIG_LEDS_BCM6358)		+= leds-bcm6358.o
>  obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
> diff --git a/drivers/leds/leds-as3645a.c b/drivers/leds/leds-as3645a.c
> new file mode 100644
> index 0000000..862d1b5
> --- /dev/null
> +++ b/drivers/leds/leds-as3645a.c
> @@ -0,0 +1,744 @@
> +/*
> + * drivers/leds/leds-as3645a.c - AS3645A and LM3555 flash controllers driver
> + *
> + * Copyright (C) 2008-2011 Nokia Corporation
> + * Copyright (c) 2011, 2017 Intel Corporation.
> + *
> + * Based on drivers/media/i2c/as3645a.c.
> + *
> + * Contact: Sakari Ailus <sakari.ailus@iki.fi>
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * General Public License for more details.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/led-class-flash.h>
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/slab.h>
> +
> +#include <media/v4l2-flash-led-class.h>
> +
> +#define AS_TIMER_US_TO_CODE(t)			(((t) / 1000 - 100) / 50)
> +#define AS_TIMER_CODE_TO_US(c)			((50 * (c) + 100) * 1000)
> +
> +/* Register definitions */
> +
> +/* Read-only Design info register: Reset state: xxxx 0001 */
> +#define AS_DESIGN_INFO_REG			0x00
> +#define AS_DESIGN_INFO_FACTORY(x)		(((x) >> 4))
> +#define AS_DESIGN_INFO_MODEL(x)			((x) & 0x0f)
> +
> +/* Read-only Version control register: Reset state: 0000 0000
> + * for first engineering samples
> + */
> +#define AS_VERSION_CONTROL_REG			0x01
> +#define AS_VERSION_CONTROL_RFU(x)		(((x) >> 4))
> +#define AS_VERSION_CONTROL_VERSION(x)		((x) & 0x0f)
> +
> +/* Read / Write	(Indicator and timer register): Reset state: 0000 1111 */
> +#define AS_INDICATOR_AND_TIMER_REG		0x02
> +#define AS_INDICATOR_AND_TIMER_TIMEOUT_SHIFT	0
> +#define AS_INDICATOR_AND_TIMER_VREF_SHIFT	4
> +#define AS_INDICATOR_AND_TIMER_INDICATOR_SHIFT	6
> +
> +/* Read / Write	(Current set register): Reset state: 0110 1001 */
> +#define AS_CURRENT_SET_REG			0x03
> +#define AS_CURRENT_ASSIST_LIGHT_SHIFT		0
> +#define AS_CURRENT_LED_DET_ON			(1 << 3)
> +#define AS_CURRENT_FLASH_CURRENT_SHIFT		4
> +
> +/* Read / Write	(Control register): Reset state: 1011 0100 */
> +#define AS_CONTROL_REG				0x04
> +#define AS_CONTROL_MODE_SETTING_SHIFT		0
> +#define AS_CONTROL_STROBE_ON			(1 << 2)
> +#define AS_CONTROL_OUT_ON			(1 << 3)
> +#define AS_CONTROL_EXT_TORCH_ON			(1 << 4)
> +#define AS_CONTROL_STROBE_TYPE_EDGE		(0 << 5)
> +#define AS_CONTROL_STROBE_TYPE_LEVEL		(1 << 5)
> +#define AS_CONTROL_COIL_PEAK_SHIFT		6
> +
> +/* Read only (D3 is read / write) (Fault and info): Reset state: 0000 x000 */
> +#define AS_FAULT_INFO_REG			0x05
> +#define AS_FAULT_INFO_INDUCTOR_PEAK_LIMIT	(1 << 1)
> +#define AS_FAULT_INFO_INDICATOR_LED		(1 << 2)
> +#define AS_FAULT_INFO_LED_AMOUNT		(1 << 3)
> +#define AS_FAULT_INFO_TIMEOUT			(1 << 4)
> +#define AS_FAULT_INFO_OVER_TEMPERATURE		(1 << 5)
> +#define AS_FAULT_INFO_SHORT_CIRCUIT		(1 << 6)
> +#define AS_FAULT_INFO_OVER_VOLTAGE		(1 << 7)
> +
> +/* Boost register */
> +#define AS_BOOST_REG				0x0d
> +#define AS_BOOST_CURRENT_DISABLE		(0 << 0)
> +#define AS_BOOST_CURRENT_ENABLE			(1 << 0)
> +
> +/* Password register is used to unlock boost register writing */
> +#define AS_PASSWORD_REG				0x0f
> +#define AS_PASSWORD_UNLOCK_VALUE		0x55
> +
> +#define AS_NAME					"as3645a"
> +#define AS_I2C_ADDR				(0x60 >> 1) /* W:0x60, R:0x61 */
> +
> +#define AS_FLASH_TIMEOUT_MIN			100000	/* us */
> +#define AS_FLASH_TIMEOUT_MAX			850000
> +#define AS_FLASH_TIMEOUT_STEP			50000
> +
> +#define AS_FLASH_INTENSITY_MIN			200000	/* uA */
> +#define AS_FLASH_INTENSITY_MAX_1LED		500000
> +#define AS_FLASH_INTENSITY_MAX_2LEDS		400000
> +#define AS_FLASH_INTENSITY_STEP			20000
> +
> +#define AS_TORCH_INTENSITY_MIN			20000	/* uA */
> +#define AS_TORCH_INTENSITY_MAX			160000
> +#define AS_TORCH_INTENSITY_STEP			20000
> +
> +#define AS_INDICATOR_INTENSITY_MIN		0	/* uA */
> +#define AS_INDICATOR_INTENSITY_MAX		10000
> +#define AS_INDICATOR_INTENSITY_STEP		2500
> +
> +#define AS_PEAK_mA_MAX				2000
> +#define AS_PEAK_mA_TO_REG(a) \
> +	((min_t(u32, AS_PEAK_mA_MAX, a) - 1250) / 250)
> +
> +enum as_mode {
> +	AS_MODE_EXT_TORCH = 0 << AS_CONTROL_MODE_SETTING_SHIFT,
> +	AS_MODE_INDICATOR = 1 << AS_CONTROL_MODE_SETTING_SHIFT,
> +	AS_MODE_ASSIST = 2 << AS_CONTROL_MODE_SETTING_SHIFT,
> +	AS_MODE_FLASH = 3 << AS_CONTROL_MODE_SETTING_SHIFT,
> +};
> +
> +struct as3645a_config {
> +	u32 flash_timeout_us;
> +	u32 flash_max_ua;
> +	u32 assist_max_ua;
> +	u32 indicator_max_ua;
> +	u32 voltage_reference;
> +	u32 peak;
> +};
> +
> +struct as3645a {
> +	struct i2c_client *client;
> +
> +	struct mutex mutex;
> +
> +	struct led_classdev_flash fled;
> +	struct led_classdev iled_cdev;
> +
> +	struct v4l2_flash *vf;
> +
> +	struct as3645a_config cfg;
> +
> +	enum as_mode mode;
> +	unsigned int timeout;
> +	unsigned int flash_current;
> +	unsigned int assist_current;
> +	unsigned int indicator_current;
> +	enum v4l2_flash_strobe_source strobe_source;
> +};
> +
> +#define fled_to_as3645a(__fled) container_of(__fled, struct as3645a, fled)
> +#define iled_cdev_to_as3645a(__iled_cdev) \
> +	container_of(__iled_cdev, struct as3645a, iled_cdev)
> +
> +/* Return negative errno else zero on success */
> +static int as3645a_write(struct as3645a *flash, u8 addr, u8 val)
> +{
> +	struct i2c_client *client = flash->client;
> +	int rval;
> +
> +	rval = i2c_smbus_write_byte_data(client, addr, val);
> +
> +	dev_dbg(&client->dev, "Write Addr:%02X Val:%02X %s\n", addr, val,
> +		rval < 0 ? "fail" : "ok");
> +
> +	return rval;
> +}
> +
> +/* Return negative errno else a data byte received from the device. */
> +static int as3645a_read(struct as3645a *flash, u8 addr)
> +{
> +	struct i2c_client *client = flash->client;
> +	int rval;
> +
> +	rval = i2c_smbus_read_byte_data(client, addr);
> +
> +	dev_dbg(&client->dev, "Read Addr:%02X Val:%02X %s\n", addr, rval,
> +		rval < 0 ? "fail" : "ok");
> +
> +	return rval;
> +}
> +
> +/* -----------------------------------------------------------------------------
> + * Hardware configuration and trigger
> + */
> +
> +/*
> + * as3645a_set_config - Set flash configuration registers
> + * @flash: The flash
> + *
> + * Configure the hardware with flash, assist and indicator currents, as well as
> + * flash timeout.
> + *
> + * Return 0 on success, or a negative error code if an I2C communication error
> + * occurred.
> + */
> +static int as3645a_set_current(struct as3645a *flash)
> +{
> +	u8 val;
> +
> +	val = (flash->flash_current << AS_CURRENT_FLASH_CURRENT_SHIFT)
> +	    | (flash->assist_current << AS_CURRENT_ASSIST_LIGHT_SHIFT)
> +	    | AS_CURRENT_LED_DET_ON;
> +
> +	return as3645a_write(flash, AS_CURRENT_SET_REG, val);
> +}
> +
> +static int as3645a_set_timeout(struct as3645a *flash)
> +{
> +	u8 val;
> +
> +	val = flash->timeout << AS_INDICATOR_AND_TIMER_TIMEOUT_SHIFT;
> +
> +	val |= (flash->cfg.voltage_reference
> +		<< AS_INDICATOR_AND_TIMER_VREF_SHIFT)
> +	    |  ((flash->indicator_current ? flash->indicator_current - 1 : 0)
> +		 << AS_INDICATOR_AND_TIMER_INDICATOR_SHIFT);
> +
> +	return as3645a_write(flash, AS_INDICATOR_AND_TIMER_REG, val);
> +}
> +
> +/*
> + * as3645a_set_control - Set flash control register
> + * @flash: The flash
> + * @mode: Desired output mode
> + * @on: Desired output state
> + *
> + * Configure the hardware with output mode and state.
> + *
> + * Return 0 on success, or a negative error code if an I2C communication error
> + * occurred.
> + */
> +static int
> +as3645a_set_control(struct as3645a *flash, enum as_mode mode, bool on)
> +{
> +	u8 reg;
> +
> +	/* Configure output parameters and operation mode. */
> +	reg = (flash->cfg.peak << AS_CONTROL_COIL_PEAK_SHIFT)
> +	    | (on ? AS_CONTROL_OUT_ON : 0)
> +	    | mode;
> +
> +	if (mode == AS_MODE_FLASH &&
> +	    flash->strobe_source == V4L2_FLASH_STROBE_SOURCE_EXTERNAL)
> +		reg |= AS_CONTROL_STROBE_TYPE_LEVEL
> +		    |  AS_CONTROL_STROBE_ON;
> +
> +	return as3645a_write(flash, AS_CONTROL_REG, reg);
> +}
> +
> +static int as3645a_get_fault(struct led_classdev_flash *fled, u32 *fault)
> +{
> +	struct as3645a *flash = fled_to_as3645a(fled);
> +	int rval;
> +
> +	/* NOTE: reading register clear fault status */
> +	rval = as3645a_read(flash, AS_FAULT_INFO_REG);
> +	if (rval < 0)
> +		return rval;
> +
> +	if (rval & AS_FAULT_INFO_INDUCTOR_PEAK_LIMIT)
> +		*fault |= LED_FAULT_OVER_CURRENT;
> +
> +	if (rval & AS_FAULT_INFO_INDICATOR_LED)
> +		*fault |= LED_FAULT_INDICATOR;
> +
> +	dev_dbg(&flash->client->dev, "%u connected LEDs\n",
> +		rval & AS_FAULT_INFO_LED_AMOUNT ? 2 : 1);
> +
> +	if (rval & AS_FAULT_INFO_TIMEOUT)
> +		*fault |= LED_FAULT_TIMEOUT;
> +
> +	if (rval & AS_FAULT_INFO_OVER_TEMPERATURE)
> +		*fault |= LED_FAULT_OVER_TEMPERATURE;
> +
> +	if (rval & AS_FAULT_INFO_SHORT_CIRCUIT)
> +		*fault |= LED_FAULT_OVER_CURRENT;
> +
> +	if (rval & AS_FAULT_INFO_OVER_VOLTAGE)
> +		*fault |= LED_FAULT_INPUT_VOLTAGE;
> +
> +	return rval;
> +}
> +
> +static unsigned int as3645a_current_to_reg(struct as3645a *flash, bool is_flash,
> +					   unsigned int ua)
> +{
> +	struct {
> +		unsigned int min;
> +		unsigned int max;
> +		unsigned int step;
> +	} __mms[] = {
> +		{
> +			AS_TORCH_INTENSITY_MIN,
> +			flash->cfg.assist_max_ua,
> +			AS_TORCH_INTENSITY_STEP
> +		},
> +		{
> +			AS_FLASH_INTENSITY_MIN,
> +			flash->cfg.flash_max_ua,
> +			AS_FLASH_INTENSITY_STEP
> +		},
> +	}, *mms = &__mms[is_flash];
> +
> +	if (ua < mms->min)
> +		ua = mms->min;
> +
> +	if (ua > mms->max)
> +		ua = mms->max;
> +
> +	return (ua - mms->min) / mms->step;
> +}
> +
> +static int as3645a_set_indicator_brightness(struct led_classdev *iled_cdev,
> +					    enum led_brightness brightness)
> +{
> +	struct as3645a *flash = iled_cdev_to_as3645a(iled_cdev);
> +	int rval;
> +
> +	flash->indicator_current = brightness;
> +
> +	rval = as3645a_set_timeout(flash);
> +	if (rval)
> +		return rval;
> +
> +	return as3645a_set_control(flash, AS_MODE_INDICATOR, brightness);
> +}
> +
> +static int as3645a_set_assist_brightness(struct led_classdev *fled_cdev,
> +					 enum led_brightness brightness)
> +{
> +	struct led_classdev_flash *fled = lcdev_to_flcdev(fled_cdev);
> +	struct as3645a *flash = fled_to_as3645a(fled);
> +	int rval;
> +
> +	if (brightness) {
> +		/* Register value 0 is 20 mA. */
> +		flash->assist_current = brightness - 1;
> +
> +		rval = as3645a_set_current(flash);
> +		if (rval)
> +			return rval;
> +	}
> +
> +	return as3645a_set_control(flash, AS_MODE_ASSIST, brightness);
> +}
> +
> +static int as3645a_set_flash_brightness(struct led_classdev_flash *fled,
> +					u32 brightness_ua)
> +{
> +	struct as3645a *flash = fled_to_as3645a(fled);
> +
> +	flash->flash_current = as3645a_current_to_reg(flash, true, brightness_ua);
> +
> +	return as3645a_set_current(flash);
> +}
> +
> +static int as3645a_set_flash_timeout(struct led_classdev_flash *fled,
> +				     u32 timeout_us)
> +{
> +	struct as3645a *flash = fled_to_as3645a(fled);
> +
> +	flash->timeout = AS_TIMER_US_TO_CODE(timeout_us);
> +
> +	return as3645a_set_timeout(flash);
> +}
> +
> +static int as3645a_set_strobe(struct led_classdev_flash *fled, bool state)
> +{
> +	struct as3645a *flash = fled_to_as3645a(fled);
> +
> +	return as3645a_set_control(flash, AS_MODE_FLASH, state);
> +}
> +
> +static const struct led_flash_ops as3645a_led_flash_ops = {
> +	.flash_brightness_set = as3645a_set_flash_brightness,
> +	.timeout_set = as3645a_set_flash_timeout,
> +	.strobe_set = as3645a_set_strobe,
> +	.fault_get = as3645a_get_fault,
> +};
> +
> +static int as3645a_setup(struct as3645a *flash)
> +{
> +	struct device *dev = &flash->client->dev;
> +	u32 fault = 0;
> +	int rval;
> +
> +	/* clear errors */
> +	rval = as3645a_read(flash, AS_FAULT_INFO_REG);
> +	if (rval < 0)
> +		return rval;
> +
> +	dev_dbg(dev, "Fault info: %02x\n", rval);
> +
> +	rval = as3645a_set_current(flash);
> +	if (rval < 0)
> +		return rval;
> +
> +	rval = as3645a_set_timeout(flash);
> +	if (rval < 0)
> +		return rval;
> +
> +	rval = as3645a_set_control(flash, AS_MODE_INDICATOR, false);
> +	if (rval < 0)
> +		return rval;
> +
> +	/* read status */
> +	rval = as3645a_get_fault(&flash->fled, &fault);
> +	if (rval < 0)
> +		return rval;
> +
> +	dev_dbg(dev, "AS_INDICATOR_AND_TIMER_REG: %02x\n",
> +		as3645a_read(flash, AS_INDICATOR_AND_TIMER_REG));
> +	dev_dbg(dev, "AS_CURRENT_SET_REG: %02x\n",
> +		as3645a_read(flash, AS_CURRENT_SET_REG));
> +	dev_dbg(dev, "AS_CONTROL_REG: %02x\n",
> +		as3645a_read(flash, AS_CONTROL_REG));
> +
> +	return rval & ~AS_FAULT_INFO_LED_AMOUNT ? -EIO : 0;
> +}
> +
> +static int as3645a_detect(struct as3645a *flash)
> +{
> +	struct device *dev = &flash->client->dev;
> +	int rval, man, model, rfu, version;
> +	const char *vendor;
> +
> +	rval = as3645a_read(flash, AS_DESIGN_INFO_REG);
> +	if (rval < 0) {
> +		dev_err(dev, "can't read design info reg\n");
> +		return rval;
> +	}
> +
> +	man = AS_DESIGN_INFO_FACTORY(rval);
> +	model = AS_DESIGN_INFO_MODEL(rval);
> +
> +	rval = as3645a_read(flash, AS_VERSION_CONTROL_REG);
> +	if (rval < 0) {
> +		dev_err(dev, "can't read version control reg\n");
> +		return rval;
> +	}
> +
> +	rfu = AS_VERSION_CONTROL_RFU(rval);
> +	version = AS_VERSION_CONTROL_VERSION(rval);
> +
> +	/* Verify the chip model and version. */
> +	if (model != 0x01 || rfu != 0x00) {
> +		dev_err(dev, "AS3645A not detected "
> +			"(model %d rfu %d)\n", model, rfu);
> +		return -ENODEV;
> +	}
> +
> +	switch (man) {
> +	case 1:
> +		vendor = "AMS, Austria Micro Systems";
> +		break;
> +	case 2:
> +		vendor = "ADI, Analog Devices Inc.";
> +		break;
> +	case 3:
> +		vendor = "NSC, National Semiconductor";
> +		break;
> +	case 4:
> +		vendor = "NXP";
> +		break;
> +	case 5:
> +		vendor = "TI, Texas Instrument";
> +		break;
> +	default:
> +		vendor = "Unknown";
> +	}
> +
> +	dev_info(dev, "Chip vendor: %s (%d) Version: %d\n", vendor,
> +		 man, version);
> +
> +	rval = as3645a_write(flash, AS_PASSWORD_REG, AS_PASSWORD_UNLOCK_VALUE);
> +	if (rval < 0)
> +		return rval;
> +
> +	return as3645a_write(flash, AS_BOOST_REG, AS_BOOST_CURRENT_DISABLE);
> +}
> +
> +static __maybe_unused int as3645a_suspend(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct as3645a *flash = i2c_get_clientdata(client);
> +	int rval;
> +
> +	rval = as3645a_set_control(flash, AS_MODE_EXT_TORCH, false);
> +	dev_dbg(dev, "Suspend %s\n", rval < 0 ? "failed" : "ok");
> +
> +	return rval;
> +}
> +
> +static __maybe_unused int as3645a_resume(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct as3645a *flash = i2c_get_clientdata(client);
> +	int rval;
> +
> +	rval = as3645a_setup(flash);
> +

nitpicking: inconsistent coding style - there is no empty line before
dev_dbg() in the as3645a_suspend().

> +	dev_dbg(dev, "Resume %s\n", rval < 0 ? "fail" : "ok");
> +
> +	return rval;
> +}
> +
> +static int as3645a_parse_node(struct as3645a *flash,
> +			      struct device_node *node)
> +{
> +	struct as3645a_config *cfg = &flash->cfg;
> +	struct device_node *child;
> +	int rval;
> +
> +	child = of_get_child_by_name(node, "flash");
> +	if (!child) {
> +		dev_err(&flash->client->dev, "can't find flash node\n");
> +		return -ENODEV;
> +	}
> +
> +	rval = of_property_read_u32(child, "flash-timeout-us",
> +				   &cfg->flash_timeout_us);
> +	if (rval < 0) {
> +		dev_err(&flash->client->dev,
> +			"can't read flash-timeout-us property for flash\n");
> +		goto out_err;
> +	}
> +
> +	rval = of_property_read_u32(child, "flash-max-microamp",
> +				   &cfg->flash_max_ua);
> +	if (rval < 0) {
> +		dev_err(&flash->client->dev,
> +			"can't read flash-max-microamp property for flash\n");
> +		goto out_err;
> +	}
> +
> +	rval = of_property_read_u32(child, "led-max-microamp",
> +				   &cfg->assist_max_ua);
> +	if (rval < 0) {
> +		dev_err(&flash->client->dev,
> +			"can't read led-max-microamp property for flash\n");
> +		goto out_err;
> +	}
> +
> +	of_property_read_u32(child, "voltage-reference",
> +			     &cfg->voltage_reference);
> +
> +	of_property_read_u32(child, "peak-current-limit", &cfg->peak);
> +	cfg->peak = AS_PEAK_mA_TO_REG(cfg->peak);
> +
> +	of_node_put(child);
> +
> +	child = of_get_child_by_name(node, "indicator");
> +	if (!child) {
> +		dev_warn(&flash->client->dev,
> +			 "can't find indicator node\n");
> +		return 0;
> +	}
> +
> +	rval = of_property_read_u32(child, "led-max-microamp",
> +				   &cfg->indicator_max_ua);
> +	if (rval < 0) {
> +		dev_err(&flash->client->dev,
> +			"can't read led-max-microamp property for indicator\n");
> +		goto out_err;
> +	}
> +
> +	of_node_put(child);
> +
> +	return 0;
> +
> +out_err:
> +	of_node_put(child);
> +
> +	return rval;
> +}
> +
> +static int as3645a_led_class_setup(struct as3645a *flash)
> +{
> +	struct led_classdev *fled_cdev = &flash->fled.led_cdev;
> +	struct led_classdev *iled_cdev = &flash->iled_cdev;
> +	struct led_flash_setting *cfg;
> +	int rval;
> +
> +	iled_cdev->name = "as3645a indicator";
> +	iled_cdev->brightness_set_blocking = as3645a_set_indicator_brightness;
> +	iled_cdev->max_brightness =
> +		flash->cfg.indicator_max_ua / AS_INDICATOR_INTENSITY_STEP;
> +
> +	rval = led_classdev_register(&flash->client->dev, iled_cdev);
> +	if (rval < 0)
> +		return rval;
> +
> +	cfg = &flash->fled.brightness;
> +	cfg->min = AS_FLASH_INTENSITY_MIN;
> +	cfg->max = flash->cfg.flash_max_ua;
> +	cfg->step = AS_FLASH_INTENSITY_STEP;
> +	cfg->val = flash->cfg.flash_max_ua;
> +
> +	cfg = &flash->fled.timeout;
> +	cfg->min = AS_FLASH_TIMEOUT_MIN;
> +	cfg->max = flash->cfg.flash_timeout_us;
> +	cfg->step = AS_FLASH_TIMEOUT_STEP;
> +	cfg->val = flash->cfg.flash_timeout_us;
> +
> +	flash->fled.ops = &as3645a_led_flash_ops;
> +
> +	fled_cdev->name = "as3645a flash";

LED class device name should be taken from label DT property,
or DT node name if the former wasn't defined.

Also LED device naming convention defines colon as a separator
between name segments.

> +	fled_cdev->brightness_set_blocking = as3645a_set_assist_brightness;
> +	/* Value 0 is off in LED class. */
> +	fled_cdev->max_brightness =
> +		as3645a_current_to_reg(flash, false,
> +				       flash->cfg.assist_max_ua) + 1;
> +	fled_cdev->flags = LED_DEV_CAP_FLASH;
> +
> +	rval = led_classdev_flash_register(&flash->client->dev, &flash->fled);
> +	if (rval) {
> +		led_classdev_unregister(iled_cdev);
> +		dev_err(&flash->client->dev,
> +			"led_classdev_flash_register() failed, error %d\n",
> +			rval);
> +	}
> +
> +	return rval;
> +}
> +
> +static int as3645a_v4l2_setup(struct as3645a *flash)
> +{
> +	struct led_classdev_flash *fled = &flash->fled;
> +	struct led_classdev *led = &fled->led_cdev;
> +	struct v4l2_flash_config cfg = {
> +		.torch_intensity = {
> +			.min = AS_TORCH_INTENSITY_MIN,
> +			.max = flash->cfg.assist_max_ua,
> +			.step = AS_TORCH_INTENSITY_STEP,
> +			.val = flash->cfg.assist_max_ua,
> +		},
> +		.indicator_intensity = {
> +			.min = AS_INDICATOR_INTENSITY_MIN,
> +			.max = flash->cfg.indicator_max_ua,
> +			.step = AS_INDICATOR_INTENSITY_STEP,
> +			.val = flash->cfg.indicator_max_ua,
> +		},
> +	};
> +
> +	strlcpy(cfg.dev_name, led->name, sizeof(cfg.dev_name));
> +
> +	flash->vf = v4l2_flash_init(&flash->client->dev, NULL, &flash->fled,
> +				    &flash->iled_cdev, NULL, &cfg);
> +	if (IS_ERR(flash->vf))
> +		return PTR_ERR(flash->vf);
> +
> +	return 0;
> +}
> +
> +static int as3645a_probe(struct i2c_client *client)
> +{
> +	struct as3645a *flash;
> +	int rval;
> +
> +	if (client->dev.of_node == NULL)
> +		return -ENODEV;
> +
> +	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
> +	if (flash == NULL)
> +		return -ENOMEM;
> +
> +	flash->client = client;
> +
> +	rval = as3645a_parse_node(flash, client->dev.of_node);
> +	if (rval < 0)
> +		return rval;
> +
> +	rval = as3645a_detect(flash);
> +	if (rval < 0)
> +		return rval;
> +
> +	mutex_init(&flash->mutex);
> +	i2c_set_clientdata(client, flash);
> +
> +	rval = as3645a_setup(flash);
> +	if (rval)
> +		goto out_mutex_destroy;
> +
> +	rval = as3645a_led_class_setup(flash);
> +	if (rval)
> +		goto out_mutex_destroy;
> +
> +	rval = as3645a_v4l2_setup(flash);
> +	if (rval)
> +		goto out_led_classdev_flash_unregister;
> +
> +	return 0;
> +
> +out_led_classdev_flash_unregister:
> +	led_classdev_flash_unregister(&flash->fled);
> +
> +out_mutex_destroy:
> +	mutex_destroy(&flash->mutex);
> +
> +	return rval;
> +}
> +
> +static int as3645a_remove(struct i2c_client *client)
> +{
> +	struct as3645a *flash = i2c_get_clientdata(client);
> +
> +	as3645a_set_control(flash, AS_MODE_EXT_TORCH, false);
> +
> +	v4l2_flash_release(flash->vf);
> +
> +	led_classdev_flash_unregister(&flash->fled);
> +	led_classdev_unregister(&flash->iled_cdev);
> +
> +	mutex_destroy(&flash->mutex);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id as3645a_of_table[] = {
> +	{ .compatible = "ams,as3645a" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, as3645a_of_table);
> +
> +SIMPLE_DEV_PM_OPS(as3645a_pm_ops, as3645a_resume, as3645a_suspend);
> +
> +static struct i2c_driver as3645a_i2c_driver = {
> +	.driver	= {
> +		.of_match_table = as3645a_of_table,
> +		.name = AS_NAME,
> +		.pm   = &as3645a_pm_ops,
> +	},
> +	.probe_new	= as3645a_probe,
> +	.remove	= as3645a_remove,
> +};
> +
> +module_i2c_driver(as3645a_i2c_driver);
> +
> +MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
> +MODULE_AUTHOR("Sakari Ailus <sakari.ailus@iki.fi>");
> +MODULE_DESCRIPTION("LED flash driver for AS3645A, LM3555 and their clones");
> +MODULE_LICENSE("GPL v2");
> 

-- 
Best regards,
Jacek Anaszewski