Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds

Pull LED subsystem updates from Bryan Wu:
"In this cycle, we merged some fix and update for LED Flash class
driver. Then the core code of LED Flash class driver is in the kernel
now. Moreover, we also got some bug fixes, code cleanup and new
drivers for LED controllers"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
leds: Don't treat the LED name as a format string
leds: Use log level warn instead of info when telling about a name clash
leds/led-class: Handle LEDs with the same name
leds: lp8860: Fix typo in MODULE_DESCRIPTION in leds-lp8860.c
leds: lp8501: Fix typo in MODULE_DESCRIPTION in leds-lp8501.c
DT: leds: Add uniqueness requirement for 'label' property.
dt-binding: leds: Add common LED DT bindings macros
leds: add Qualcomm PM8941 WLED driver
leds: add DT binding for Qualcomm PM8941 WLED block
leds: pca963x: Add missing initialiation of struct led_info.flags
leds: flash: Fix the size of sysfs_groups array
Documentation: leds: Add description of LED Flash class extension
leds: flash: document sysfs interface
leds: flash: Remove synchronized flash strobe feature
leds: Introduce devres helper for led_classdev_register
leds: lp8860: make use of devm_gpiod_get_optional
leds: Let the binding document example for leds-gpio follow the gpio bindings
leds: flash: remove stray include directive
leds: leds-pwm: drop one pwm_get_period() call

Documentation/ABI/testing/sysfs-class-led-flash

···
+What:		/sys/class/leds/<led>/flash_brightness
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read/write
+		Set the brightness of this LED in the flash strobe mode, in
+		microamperes. The file is created only for the flash LED devices
+		that support setting flash brightness.
+
+		The value is between 0 and
+		/sys/class/leds/<led>/max_flash_brightness.
+
+What:		/sys/class/leds/<led>/max_flash_brightness
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read only
+		Maximum brightness level for this LED in the flash strobe mode,
+		in microamperes.
+
+What:		/sys/class/leds/<led>/flash_timeout
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read/write
+		Hardware timeout for flash, in microseconds. The flash strobe
+		is stopped after this period of time has passed from the start
+		of the strobe. The file is created only for the flash LED
+		devices that support setting flash timeout.
+
+What:		/sys/class/leds/<led>/max_flash_timeout
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read only
+		Maximum flash timeout for this LED, in microseconds.
+
+What:		/sys/class/leds/<led>/flash_strobe
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read/write
+		Flash strobe state. When written with 1 it triggers flash strobe
+		and when written with 0 it turns the flash off.
+
+		On read 1 means that flash is currently strobing and 0 means
+		that flash is off.
+
+What:		/sys/class/leds/<led>/flash_fault
+Date:		March 2015
+KernelVersion:	4.0
+Contact:	Jacek Anaszewski <[e-mail]>
+Description:	read only
+		Space separated list of flash faults that may have occurred.
+		Flash faults are re-read after strobing the flash. Possible
+		flash faults:
+
+		* led-over-voltage - flash controller voltage to the flash LED
+			has exceeded the limit specific to the flash controller
+		* flash-timeout-exceeded - the flash strobe was still on when
+			the timeout set by the user has expired; not all flash
+			controllers may set this in all such conditions
+		* controller-over-temperature - the flash controller has
+			overheated
+		* controller-short-circuit - the short circuit protection
+			of the flash controller has been triggered
+		* led-power-supply-over-current - current in the LED power
+			supply has exceeded the limit specific to the flash
+			controller
+		* indicator-led-fault - the flash controller has detected
+			a short or open circuit condition on the indicator LED
+		* led-under-voltage - flash controller voltage to the flash
+			LED has been below the minimum limit specific to
+			the flash
+		* controller-under-voltage - the input voltage of the flash
+			controller is below the limit under which strobing the
+			flash at full current will not be possible;
+			the condition persists until this flag is no longer set
+		* led-over-temperature - the temperature of the LED has exceeded
+			its allowed upper limit

Documentation/devicetree/bindings/leds/common.txt

···
 - led-sources : List of device current outputs the LED is connected to. The
 		outputs are identified by the numbers that must be defined
 		in the LED device binding documentation.
-- label : The label for this LED.  If omitted, the label is
-  taken from the node name (excluding the unit address).
+- label : The label for this LED. If omitted, the label is taken from the node
+	  name (excluding the unit address). It has to uniquely identify
+	  a device, i.e. no other LED class device can be assigned the same
+	  label.
 
 - linux,default-trigger :  This parameter, if present, is a
     string defining the trigger assigned to the LED.  Current triggers are:

Documentation/devicetree/bindings/leds/leds-gpio.txt

···
 
 Examples:
 
+#include <dt-bindings/gpio/gpio.h>
+
 leds {
 	compatible = "gpio-leds";
 	hdd {
 		label = "IDE Activity";
-		gpios = <&mcu_pio 0 1>; /* Active low */
+		gpios = <&mcu_pio 0 GPIO_ACTIVE_LOW>;
 		linux,default-trigger = "ide-disk";
 	};
 
 	fault {
-		gpios = <&mcu_pio 1 0>;
+		gpios = <&mcu_pio 1 GPIO_ACTIVE_HIGH>;
 		/* Keep LED on if BIOS detected hardware fault */
 		default-state = "keep";
 	};
···
 run-control {
 	compatible = "gpio-leds";
 	red {
-		gpios = <&mpc8572 6 0>;
+		gpios = <&mpc8572 6 GPIO_ACTIVE_HIGH>;
 		default-state = "off";
 	};
 	green {
-		gpios = <&mpc8572 7 0>;
+		gpios = <&mpc8572 7 GPIO_ACTIVE_HIGH>;
 		default-state = "on";
 	};
 };
···
 	compatible = "gpio-leds";
 
 	charger-led {
-		gpios = <&gpio1 2 0>;
+		gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
 		linux,default-trigger = "max8903-charger-charging";
 		retain-state-suspended;
 	};

Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt

···
+Binding for Qualcomm PM8941 WLED driver
+
+Required properties:
+- compatible: should be "qcom,pm8941-wled"
+- reg: slave address
+
+Optional properties:
+- label: The label for this led
+  See Documentation/devicetree/bindings/leds/common.txt
+- linux,default-trigger: Default trigger assigned to the LED
+  See Documentation/devicetree/bindings/leds/common.txt
+- qcom,cs-out: bool; enable current sink output
+- qcom,cabc: bool; enable content adaptive backlight control
+- qcom,ext-gen: bool; use externally generated modulator signal to dim
+- qcom,current-limit: mA; per-string current limit; value from 0 to 25
+	default: 20mA
+- qcom,current-boost-limit: mA; boost current limit; one of:
+	105, 385, 525, 805, 980, 1260, 1400, 1680
+	default: 805mA
+- qcom,switching-freq: kHz; switching frequency; one of:
+	600, 640, 685, 738, 800, 872, 960, 1066, 1200, 1371,
+	1600, 1920, 2400, 3200, 4800, 9600,
+	default: 1600kHz
+- qcom,ovp: V; Over-voltage protection limit; one of:
+	27, 29, 32, 35
+	default: 29V
+- qcom,num-strings: #; number of led strings attached; value from 1 to 3
+	default: 2
+
+Example:
+
+pm8941-wled@d800 {
+	compatible = "qcom,pm8941-wled";
+	reg = <0xd800>;
+	label = "backlight";
+
+	qcom,cs-out;
+	qcom,current-limit = <20>;
+	qcom,current-boost-limit = <805>;
+	qcom,switching-freq = <1600>;
+	qcom,ovp = <29>;
+	qcom,num-strings = <2>;
+};

Documentation/driver-model/devres.txt

···
   devm_request_irq()
   devm_request_threaded_irq()
 
+LED
+  devm_led_classdev_register()
+  devm_led_classdev_unregister()
+
 MDIO
   devm_mdiobus_alloc()
   devm_mdiobus_alloc_size()

Documentation/leds/leds-class-flash.txt

···
+
+Flash LED handling under Linux
+==============================
+
+Some LED devices provide two modes - torch and flash. In the LED subsystem
+those modes are supported by LED class (see Documentation/leds/leds-class.txt)
+and LED Flash class respectively. The torch mode related features are enabled
+by default and the flash ones only if a driver declares it by setting
+LED_DEV_CAP_FLASH flag.
+
+In order to enable the support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol
+must be defined in the kernel config. A LED Flash class driver must be
+registered in the LED subsystem with led_classdev_flash_register function.
+
+Following sysfs attributes are exposed for controlling flash LED devices:
+(see Documentation/ABI/testing/sysfs-class-led-flash)
+	- flash_brightness
+	- max_flash_brightness
+	- flash_timeout
+	- max_flash_timeout
+	- flash_strobe
+	- flash_fault

drivers/leds/Kconfig

···
 	  This option enabled support for the LEDs on the ARM Versatile
 	  and RealView boards. Say Y to enabled these.
 
+config LEDS_PM8941_WLED
+	tristate "LED support for the Qualcomm PM8941 WLED block"
+	depends on LEDS_CLASS
+	select REGMAP
+	help
+	  This option enables support for the 'White' LED block
+	  on Qualcomm PM8941 PMICs.
+
 comment "LED Triggers"
 source "drivers/leds/trigger/Kconfig"
 

drivers/leds/Makefile

···
 obj-$(CONFIG_LEDS_SYSCON)		+= leds-syscon.o
 obj-$(CONFIG_LEDS_VERSATILE)		+= leds-versatile.o
 obj-$(CONFIG_LEDS_MENF21BMC)		+= leds-menf21bmc.o
+obj-$(CONFIG_LEDS_PM8941_WLED)		+= leds-pm8941-wled.o
 
 # LED SPI Drivers
 obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o

drivers/leds/led-class-flash.c

···
 }
 static DEVICE_ATTR_RO(flash_fault);
 
-static ssize_t available_sync_leds_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct led_classdev *led_cdev = dev_get_drvdata(dev);
-	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
-	char *pbuf = buf;
-	int i, buf_len;
-
-	buf_len = sprintf(pbuf, "[0: none] ");
-	pbuf += buf_len;
-
-	for (i = 0; i < fled_cdev->num_sync_leds; ++i) {
-		buf_len = sprintf(pbuf, "[%d: %s] ", i + 1,
-				  fled_cdev->sync_leds[i]->led_cdev.name);
-		pbuf += buf_len;
-	}
-
-	return sprintf(buf, "%s\n", buf);
-}
-static DEVICE_ATTR_RO(available_sync_leds);
-
-static ssize_t flash_sync_strobe_store(struct device *dev,
-		struct device_attribute *attr, const char *buf, size_t size)
-{
-	struct led_classdev *led_cdev = dev_get_drvdata(dev);
-	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
-	unsigned long led_id;
-	ssize_t ret;
-
-	mutex_lock(&led_cdev->led_access);
-
-	if (led_sysfs_is_disabled(led_cdev)) {
-		ret = -EBUSY;
-		goto unlock;
-	}
-
-	ret = kstrtoul(buf, 10, &led_id);
-	if (ret)
-		goto unlock;
-
-	if (led_id > fled_cdev->num_sync_leds) {
-		ret = -ERANGE;
-		goto unlock;
-	}
-
-	fled_cdev->sync_led_id = led_id;
-
-	ret = size;
-unlock:
-	mutex_unlock(&led_cdev->led_access);
-	return ret;
-}
-
-static ssize_t flash_sync_strobe_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
-{
-	struct led_classdev *led_cdev = dev_get_drvdata(dev);
-	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
-	int sled_id = fled_cdev->sync_led_id;
-	char *sync_led_name = "none";
-
-	if (fled_cdev->sync_led_id > 0)
-		sync_led_name = (char *)
-			fled_cdev->sync_leds[sled_id - 1]->led_cdev.name;
-
-	return sprintf(buf, "[%d: %s]\n", sled_id, sync_led_name);
-}
-static DEVICE_ATTR_RW(flash_sync_strobe);
-
 static struct attribute *led_flash_strobe_attrs[] = {
 	&dev_attr_flash_strobe.attr,
 	NULL,
···
 	NULL,
 };
 
-static struct attribute *led_flash_sync_strobe_attrs[] = {
-	&dev_attr_available_sync_leds.attr,
-	&dev_attr_flash_sync_strobe.attr,
-	NULL,
-};
-
 static const struct attribute_group led_flash_strobe_group = {
 	.attrs = led_flash_strobe_attrs,
 };
···
 
 static const struct attribute_group led_flash_fault_group = {
 	.attrs = led_flash_fault_attrs,
-};
-
-static const struct attribute_group led_flash_sync_strobe_group = {
-	.attrs = led_flash_sync_strobe_attrs,
 };
 
 static void led_flash_resume(struct led_classdev *led_cdev)
···
 
 	if (ops->fault_get)
 		flash_groups[num_sysfs_groups++] = &led_flash_fault_group;
-
-	if (led_cdev->flags & LED_DEV_CAP_SYNC_STROBE)
-		flash_groups[num_sysfs_groups++] = &led_flash_sync_strobe_group;
 
 	led_cdev->groups = flash_groups;
 }

drivers/leds/led-class.c

···
 	.resume         = led_resume,
 };
 
+static int match_name(struct device *dev, const void *data)
+{
+	if (!dev_name(dev))
+		return 0;
+	return !strcmp(dev_name(dev), (char *)data);
+}
+
+static int led_classdev_next_name(const char *init_name, char *name,
+				  size_t len)
+{
+	unsigned int i = 0;
+	int ret = 0;
+
+	strlcpy(name, init_name, len);
+
+	while (class_find_device(leds_class, NULL, name, match_name) &&
+	       (ret < len))
+		ret = snprintf(name, len, "%s_%u", init_name, ++i);
+
+	if (ret >= len)
+		return -ENOMEM;
+
+	return i;
+}
+
 /**
  * led_classdev_register - register a new object of led_classdev class.
  * @parent: The device to register.
···
  */
 int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
 {
+	char name[64];
+	int ret;
+
+	ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
+	if (ret < 0)
+		return ret;
+
 	led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
-					led_cdev, led_cdev->groups,
-					"%s", led_cdev->name);
+				led_cdev, led_cdev->groups, "%s", name);
 	if (IS_ERR(led_cdev->dev))
 		return PTR_ERR(led_cdev->dev);
+
+	if (ret)
+		dev_warn(parent, "Led %s renamed to %s due to name collision",
+				led_cdev->name, dev_name(led_cdev->dev));
 
 #ifdef CONFIG_LEDS_TRIGGERS
 	init_rwsem(&led_cdev->trigger_lock);
···
 	mutex_destroy(&led_cdev->led_access);
 }
 EXPORT_SYMBOL_GPL(led_classdev_unregister);
+
+static void devm_led_classdev_release(struct device *dev, void *res)
+{
+	led_classdev_unregister(*(struct led_classdev **)res);
+}
+
+/**
+ * devm_led_classdev_register - resource managed led_classdev_register()
+ * @parent: The device to register.
+ * @led_cdev: the led_classdev structure for this device.
+ */
+int devm_led_classdev_register(struct device *parent,
+			       struct led_classdev *led_cdev)
+{
+	struct led_classdev **dr;
+	int rc;
+
+	dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
+	if (!dr)
+		return -ENOMEM;
+
+	rc = led_classdev_register(parent, led_cdev);
+	if (rc) {
+		devres_free(dr);
+		return rc;
+	}
+
+	*dr = led_cdev;
+	devres_add(parent, dr);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_led_classdev_register);
+
+static int devm_led_classdev_match(struct device *dev, void *res, void *data)
+{
+	struct led_cdev **p = res;
+
+	if (WARN_ON(!p || !*p))
+		return 0;
+
+	return *p == data;
+}
+
+/**
+ * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
+ * @parent: The device to unregister.
+ * @led_cdev: the led_classdev structure for this device.
+ */
+void devm_led_classdev_unregister(struct device *dev,
+				  struct led_classdev *led_cdev)
+{
+	WARN_ON(devres_release(dev,
+			       devm_led_classdev_release,
+			       devm_led_classdev_match, led_cdev));
+}
+EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
 
 static int __init leds_init(void)
 {

drivers/leds/leds-lp8501.c

···
 
 module_i2c_driver(lp8501_driver);
 
-MODULE_DESCRIPTION("Texas Instruments LP8501 LED drvier");
+MODULE_DESCRIPTION("Texas Instruments LP8501 LED driver");
 MODULE_AUTHOR("Milo Kim");
 MODULE_LICENSE("GPL");

drivers/leds/leds-lp8860.c

···
 		}
 	}
 
-	led->enable_gpio = devm_gpiod_get(&client->dev, "enable");
-	if (IS_ERR(led->enable_gpio))
-		led->enable_gpio = NULL;
-	else
-		gpiod_direction_output(led->enable_gpio, 0);
+	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
+						   "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(led->enable_gpio)) {
+		ret = PTR_ERR(led->enable_gpio);
+		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
+		return ret;
+	}
 
 	led->regulator = devm_regulator_get(&client->dev, "vled");
 	if (IS_ERR(led->regulator))
···
 };
 module_i2c_driver(lp8860_driver);
 
-MODULE_DESCRIPTION("Texas Instruments LP8860 LED drvier");
+MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
 MODULE_AUTHOR("Dan Murphy <[e-mail]>");
 MODULE_LICENSE("GPL");

drivers/leds/leds-pca963x.c

···
 		return ERR_PTR(-ENOMEM);
 
 	for_each_child_of_node(np, child) {
-		struct led_info led;
+		struct led_info led = {};
 		u32 reg;
 		int res;
 

drivers/leds/leds-pm8941-wled.c

···
+/* Copyright (c) 2015, Sony Mobile Communications, AB.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+#define PM8941_WLED_REG_VAL_BASE		0x40
+#define  PM8941_WLED_REG_VAL_MAX		0xFFF
+
+#define PM8941_WLED_REG_MOD_EN			0x46
+#define  PM8941_WLED_REG_MOD_EN_BIT		BIT(7)
+#define  PM8941_WLED_REG_MOD_EN_MASK		BIT(7)
+
+#define PM8941_WLED_REG_SYNC			0x47
+#define  PM8941_WLED_REG_SYNC_MASK		0x07
+#define  PM8941_WLED_REG_SYNC_LED1		BIT(0)
+#define  PM8941_WLED_REG_SYNC_LED2		BIT(1)
+#define  PM8941_WLED_REG_SYNC_LED3		BIT(2)
+#define  PM8941_WLED_REG_SYNC_ALL		0x07
+#define  PM8941_WLED_REG_SYNC_CLEAR		0x00
+
+#define PM8941_WLED_REG_FREQ			0x4c
+#define  PM8941_WLED_REG_FREQ_MASK		0x0f
+
+#define PM8941_WLED_REG_OVP			0x4d
+#define  PM8941_WLED_REG_OVP_MASK		0x03
+
+#define PM8941_WLED_REG_BOOST			0x4e
+#define  PM8941_WLED_REG_BOOST_MASK		0x07
+
+#define PM8941_WLED_REG_SINK			0x4f
+#define  PM8941_WLED_REG_SINK_MASK		0xe0
+#define  PM8941_WLED_REG_SINK_SHFT		0x05
+
+/* Per-'string' registers below */
+#define PM8941_WLED_REG_STR_OFFSET		0x10
+
+#define PM8941_WLED_REG_STR_MOD_EN_BASE		0x60
+#define  PM8941_WLED_REG_STR_MOD_MASK		BIT(7)
+#define  PM8941_WLED_REG_STR_MOD_EN		BIT(7)
+
+#define PM8941_WLED_REG_STR_SCALE_BASE		0x62
+#define  PM8941_WLED_REG_STR_SCALE_MASK		0x1f
+
+#define PM8941_WLED_REG_STR_MOD_SRC_BASE	0x63
+#define  PM8941_WLED_REG_STR_MOD_SRC_MASK	0x01
+#define  PM8941_WLED_REG_STR_MOD_SRC_INT	0x00
+#define  PM8941_WLED_REG_STR_MOD_SRC_EXT	0x01
+
+#define PM8941_WLED_REG_STR_CABC_BASE		0x66
+#define  PM8941_WLED_REG_STR_CABC_MASK		BIT(7)
+#define  PM8941_WLED_REG_STR_CABC_EN		BIT(7)
+
+struct pm8941_wled_config {
+	u32 i_boost_limit;
+	u32 ovp;
+	u32 switch_freq;
+	u32 num_strings;
+	u32 i_limit;
+	bool cs_out_en;
+	bool ext_gen;
+	bool cabc_en;
+};
+
+struct pm8941_wled {
+	struct regmap *regmap;
+	u16 addr;
+
+	struct led_classdev cdev;
+
+	struct pm8941_wled_config cfg;
+};
+
+static int pm8941_wled_set(struct led_classdev *cdev,
+			   enum led_brightness value)
+{
+	struct pm8941_wled *wled;
+	u8 ctrl = 0;
+	u16 val;
+	int rc;
+	int i;
+
+	wled = container_of(cdev, struct pm8941_wled, cdev);
+
+	if (value != 0)
+		ctrl = PM8941_WLED_REG_MOD_EN_BIT;
+
+	val = value * PM8941_WLED_REG_VAL_MAX / LED_FULL;
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_MOD_EN,
+			PM8941_WLED_REG_MOD_EN_MASK, ctrl);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < wled->cfg.num_strings; ++i) {
+		u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
+
+		rc = regmap_bulk_write(wled->regmap,
+				wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
+				v, 2);
+		if (rc)
+			return rc;
+	}
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_SYNC,
+			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
+	if (rc)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_SYNC,
+			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
+	return rc;
+}
+
+static void pm8941_wled_set_brightness(struct led_classdev *cdev,
+				       enum led_brightness value)
+{
+	if (pm8941_wled_set(cdev, value)) {
+		dev_err(cdev->dev, "Unable to set brightness\n");
+		return;
+	}
+	cdev->brightness = value;
+}
+
+static int pm8941_wled_setup(struct pm8941_wled *wled)
+{
+	int rc;
+	int i;
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_OVP,
+			PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
+	if (rc)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_BOOST,
+			PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
+	if (rc)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+			wled->addr + PM8941_WLED_REG_FREQ,
+			PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
+	if (rc)
+		return rc;
+
+	if (wled->cfg.cs_out_en) {
+		u8 all = (BIT(wled->cfg.num_strings) - 1)
+				<< PM8941_WLED_REG_SINK_SHFT;
+
+		rc = regmap_update_bits(wled->regmap,
+				wled->addr + PM8941_WLED_REG_SINK,
+				PM8941_WLED_REG_SINK_MASK, all);
+		if (rc)
+			return rc;
+	}
+
+	for (i = 0; i < wled->cfg.num_strings; ++i) {
+		u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
+
+		rc = regmap_update_bits(wled->regmap,
+				addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
+				PM8941_WLED_REG_STR_MOD_MASK,
+				PM8941_WLED_REG_STR_MOD_EN);
+		if (rc)
+			return rc;
+
+		if (wled->cfg.ext_gen) {
+			rc = regmap_update_bits(wled->regmap,
+					addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
+					PM8941_WLED_REG_STR_MOD_SRC_MASK,
+					PM8941_WLED_REG_STR_MOD_SRC_EXT);
+			if (rc)
+				return rc;
+		}
+
+		rc = regmap_update_bits(wled->regmap,
+				addr + PM8941_WLED_REG_STR_SCALE_BASE,
+				PM8941_WLED_REG_STR_SCALE_MASK,
+				wled->cfg.i_limit);
+		if (rc)
+			return rc;
+
+		rc = regmap_update_bits(wled->regmap,
+				addr + PM8941_WLED_REG_STR_CABC_BASE,
+				PM8941_WLED_REG_STR_CABC_MASK,
+				wled->cfg.cabc_en ?
+					PM8941_WLED_REG_STR_CABC_EN : 0);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+static const struct pm8941_wled_config pm8941_wled_config_defaults = {
+	.i_boost_limit = 3,
+	.i_limit = 20,
+	.ovp = 2,
+	.switch_freq = 5,
+	.num_strings = 0,
+	.cs_out_en = false,
+	.ext_gen = false,
+	.cabc_en = false,
+};
+
+struct pm8941_wled_var_cfg {
+	const u32 *values;
+	u32 (*fn)(u32);
+	int size;
+};
+
+static const u32 pm8941_wled_i_boost_limit_values[] = {
+	105, 385, 525, 805, 980, 1260, 1400, 1680,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
+	.values = pm8941_wled_i_boost_limit_values,
+	.size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
+};
+
+static const u32 pm8941_wled_ovp_values[] = {
+	35, 32, 29, 27,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
+	.values = pm8941_wled_ovp_values,
+	.size = ARRAY_SIZE(pm8941_wled_ovp_values),
+};
+
+static u32 pm8941_wled_num_strings_values_fn(u32 idx)
+{
+	return idx + 1;
+}
+
+static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
+	.fn = pm8941_wled_num_strings_values_fn,
+	.size = 3,
+};
+
+static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
+{
+	return 19200 / (2 * (1 + idx));
+}
+
+static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
+	.fn = pm8941_wled_switch_freq_values_fn,
+	.size = 16,
+};
+
+static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
+	.size = 26,
+};
+
+static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
+{
+	if (idx >= cfg->size)
+		return UINT_MAX;
+	if (cfg->fn)
+		return cfg->fn(idx);
+	if (cfg->values)
+		return cfg->values[idx];
+	return idx;
+}
+
+static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
+{
+	struct pm8941_wled_config *cfg = &wled->cfg;
+	u32 val;
+	int rc;
+	u32 c;
+	int i;
+	int j;
+
+	const struct {
+		const char *name;
+		u32 *val_ptr;
+		const struct pm8941_wled_var_cfg *cfg;
+	} u32_opts[] = {
+		{
+			"qcom,current-boost-limit",
+			&cfg->i_boost_limit,
+			.cfg = &pm8941_wled_i_boost_limit_cfg,
+		},
+		{
+			"qcom,current-limit",
+			&cfg->i_limit,
+			.cfg = &pm8941_wled_i_limit_cfg,
+		},
+		{
+			"qcom,ovp",
+			&cfg->ovp,
+			.cfg = &pm8941_wled_ovp_cfg,
+		},
+		{
+			"qcom,switching-freq",
+			&cfg->switch_freq,
+			.cfg = &pm8941_wled_switch_freq_cfg,
+		},
+		{
+			"qcom,num-strings",
+			&cfg->num_strings,
+			.cfg = &pm8941_wled_num_strings_cfg,
+		},
+	};
+	const struct {
+		const char *name;
+		bool *val_ptr;
+	} bool_opts[] = {
+		{ "qcom,cs-out", &cfg->cs_out_en, },
+		{ "qcom,ext-gen", &cfg->ext_gen, },
+		{ "qcom,cabc", &cfg->cabc_en, },
+	};
+
+	rc = of_property_read_u32(dev->of_node, "reg", &val);
+	if (rc || val > 0xffff) {
+		dev_err(dev, "invalid IO resources\n");
+		return rc ? rc : -EINVAL;
+	}
+	wled->addr = val;
+
+	rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
+	if (rc)
+		wled->cdev.name = dev->of_node->name;
+
+	wled->cdev.default_trigger = of_get_property(dev->of_node,
+			"linux,default-trigger", NULL);
+
+	*cfg = pm8941_wled_config_defaults;
+	for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
+		rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
+		if (rc == -EINVAL) {
+			continue;
+		} else if (rc) {
+			dev_err(dev, "error reading '%s'\n", u32_opts[i].name);
+			return rc;
+		}
+
+		c = UINT_MAX;
+		for (j = 0; c != val; j++) {
+			c = pm8941_wled_values(u32_opts[i].cfg, j);
+			if (c == UINT_MAX) {
+				dev_err(dev, "invalid value for '%s'\n",
+					u32_opts[i].name);
+				return -EINVAL;
+			}
+		}
+
+		dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, c);
+		*u32_opts[i].val_ptr = j;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
+		if (of_property_read_bool(dev->of_node, bool_opts[i].name))
+			*bool_opts[i].val_ptr = true;
+	}
+
+	cfg->num_strings = cfg->num_strings + 1;
+
+	return 0;
+}
+
+static int pm8941_wled_probe(struct platform_device *pdev)
+{
+	struct pm8941_wled *wled;
+	struct regmap *regmap;
+	int rc;
+
+	regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!regmap) {
+		dev_err(&pdev->dev, "Unable to get regmap\n");
+		return -EINVAL;
+	}
+
+	wled = devm_kzalloc(&pdev->dev, sizeof(*wled), GFP_KERNEL);
+	if (!wled)
+		return -ENOMEM;
+
+	wled->regmap = regmap;
+
+	rc = pm8941_wled_configure(wled, &pdev->dev);
+	if (rc)
+		return rc;
+
+	rc = pm8941_wled_setup(wled);
+	if (rc)
+		return rc;
+
+	wled->cdev.brightness_set = pm8941_wled_set_brightness;
+
+	rc = devm_led_classdev_register(&pdev->dev, &wled->cdev);
+	if (rc)
+		return rc;
+
+	platform_set_drvdata(pdev, wled);
+
+	return 0;
+};
+
+static const struct of_device_id pm8941_wled_match_table[] = {
+	{ .compatible = "qcom,pm8941-wled" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, pm8941_wled_match_table);
+
+static struct platform_driver pm8941_wled_driver = {
+	.probe = pm8941_wled_probe,
+	.driver	= {
+		.name = "pm8941-wled",
+		.of_match_table	= pm8941_wled_match_table,
+	},
+};
+
+module_platform_driver(pm8941_wled_driver);
+
+MODULE_DESCRIPTION("pm8941 wled driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:pm8941-wled");

drivers/leds/leds-pwm.c

···
 		return ret;
 	}
 
-	if (child)
-		led_data->period = pwm_get_period(led_data->pwm);
-
 	led_data->can_sleep = pwm_can_sleep(led_data->pwm);
 	if (led_data->can_sleep)
 		INIT_WORK(&led_data->work, led_pwm_work);

include/dt-bindings/leds/common.h

···
+/*
+ * This header provides macros for the common LEDs device tree bindings.
+ *
+ * Copyright (C) 2015, Samsung Electronics Co., Ltd.
+ *
+ * Author: Jacek Anaszewski <[e-mail]>
+ */
+
+#ifndef __DT_BINDINGS_LEDS_H__
+#define __DT_BINDINGS_LEDS_H
+
+/* External trigger type */
+#define LEDS_TRIG_TYPE_EDGE	0
+#define LEDS_TRIG_TYPE_LEVEL	1
+
+/* Boost modes */
+#define LEDS_BOOST_OFF		0
+#define LEDS_BOOST_ADAPTIVE	1
+#define LEDS_BOOST_FIXED	2
+
+#endif /* __DT_BINDINGS_LEDS_H */

include/linux/led-class-flash.h

···
 #define __LINUX_FLASH_LEDS_H_INCLUDED
 
 #include <linux/leds.h>
-#include <uapi/linux/v4l2-controls.h>
 
 struct device_node;
 struct led_classdev_flash;
···
 #define LED_FAULT_LED_OVER_TEMPERATURE	(1 << 8)
 #define LED_NUM_FLASH_FAULTS		9
 
-#define LED_FLASH_MAX_SYSFS_GROUPS 7
+#define LED_FLASH_SYSFS_GROUPS_SIZE	5
 
 struct led_flash_ops {
 	/* set flash brightness */
···
 	struct led_flash_setting timeout;
 
 	/* LED Flash class sysfs groups */
-	const struct attribute_group *sysfs_groups[LED_FLASH_MAX_SYSFS_GROUPS];
-
-	/* LEDs available for flash strobe synchronization */
-	struct led_classdev_flash **sync_leds;
-
-	/* Number of LEDs available for flash strobe synchronization */
-	int num_sync_leds;
-
-	/*
-	 * The identifier of the sub-led to synchronize the flash strobe with.
-	 * Identifiers start from 1, which reflects the first element from the
-	 * sync_leds array. 0 means that the flash strobe should not be
-	 * synchronized.
-	 */
-	u32 sync_led_id;
+	const struct attribute_group *sysfs_groups[LED_FLASH_SYSFS_GROUPS_SIZE];
 };
 
 static inline struct led_classdev_flash *lcdev_to_flcdev(

include/linux/leds.h

···
 #define SET_BRIGHTNESS_ASYNC	(1 << 21)
 #define SET_BRIGHTNESS_SYNC	(1 << 22)
 #define LED_DEV_CAP_FLASH	(1 << 23)
-#define LED_DEV_CAP_SYNC_STROBE	(1 << 24)
 
 	/* Set LED brightness level */
 	/* Must not sleep, use a workqueue if needed */
···
 
 extern int led_classdev_register(struct device *parent,
 				 struct led_classdev *led_cdev);
+extern int devm_led_classdev_register(struct device *parent,
+				      struct led_classdev *led_cdev);
 extern void led_classdev_unregister(struct led_classdev *led_cdev);
+extern void devm_led_classdev_unregister(struct device *parent,
+					 struct led_classdev *led_cdev);
 extern void led_classdev_suspend(struct led_classdev *led_cdev);
 extern void led_classdev_resume(struct led_classdev *led_cdev);