[PATCH v4 0/3] Add sy7802 flash led driver

[PATCH v4 0/3] Add sy7802 flash led driver

[André Apitzsch via B4 Relay]

This series introduces a driver for the Silergy SY7802 charge pump used
in the BQ Aquaris M5 and X5 smartphones.

The implementation is based on information extracted from downstream as
the datasheet provided by a distributor of the hardware didn't include
any information about the i2c register description.

Signed-off-by: André Apitzsch <git@apitzsch.eu>
---
Changes in v4:
- Use for_each_available_child_of_node_scoped() to simplify code
- Use dev_err_probe() to be consistent with the other code in
  sy7802_probe()
- Split devm_add_action() into 2 devm_add_action_or_reset() to simplify
  code and balance regulator_enable()
- Link to v3: https://lore.kernel.org/r/20240612-sy7802-v3-0-1e9cc1c79b79@apitzsch.eu

Changes in v3:
- Add R-b tag to first patch
- Extend driver commit message
- Improve readability of defines by using BIT()
- Rename some variables/parameters
  * led_no -> led_id
  * level -> brightness
  * curr -> fled_{strobe,torch}_used_tmp
  * mask -> {flash,torch}_mask
  * i -> child_num
- Restructure structs ("Place th big stuff at the top")
- Declare 'child' on a separate line
- Move multi-line assignments out of declaration block
- Update warning/error messages and comments
- Use gotos to handle error path
- Use devm API to cleanup module's resources
- Init mutex before LED class device is registered to avoid race
  condition
- Link to v2: https://lore.kernel.org/r/20240401-sy7802-v2-0-1138190a7448@apitzsch.eu

Changes in v2:
- bindings: remove unneeded allOf
- bindings: example: move flash-led-controller under i2c node to fix
  check error
- Cc to phone-devel
- Link to v1: https://lore.kernel.org/r/20240327-sy7802-v1-0-db74ab32faaf@apitzsch.eu

---
André Apitzsch (3):
      dt-bindings: leds: Add Silergy SY7802 flash LED
      leds: sy7802: Add support for Silergy SY7802 flash LED controller
      arm64: dts: qcom: msm8939-longcheer-l9100: Add rear flash

 .../devicetree/bindings/leds/silergy,sy7802.yaml   | 100 ++++
 .../boot/dts/qcom/msm8939-longcheer-l9100.dts      |  26 +
 drivers/leds/flash/Kconfig                         |  11 +
 drivers/leds/flash/Makefile                        |   1 +
 drivers/leds/flash/leds-sy7802.c                   | 542 +++++++++++++++++++++
 5 files changed, 680 insertions(+)
---
base-commit: 6a03b35e4395eb2d6e89a38aca00a9fe9cb39ba1
change-id: 20240325-sy7802-f40fc6f56525

Best regards,
-- 
André Apitzsch <git@apitzsch.eu>

[PATCH v4 1/3] dt-bindings: leds: Add Silergy SY7802 flash LED

[André Apitzsch via B4 Relay]

From: André Apitzsch <git@apitzsch.eu>

Document Silergy SY7802 flash LED driver devicetree bindings.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: André Apitzsch <git@apitzsch.eu>
---
 .../devicetree/bindings/leds/silergy,sy7802.yaml   | 100 +++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/Documentation/devicetree/bindings/leds/silergy,sy7802.yaml b/Documentation/devicetree/bindings/leds/silergy,sy7802.yaml
new file mode 100644
index 000000000000..46b8e5452b62
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/silergy,sy7802.yaml
@@ -0,0 +1,100 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/silergy,sy7802.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Silergy SY7802 1800mA Boost Charge Pump LED Driver
+
+maintainers:
+  - André Apitzsch <git@apitzsch.eu>
+
+description: |
+  The SY7802 is a current-regulated charge pump which can regulate two current
+  levels for Flash and Torch modes.
+
+  The SY7802 is a high-current synchronous boost converter with 2-channel
+  high side current sources. Each channel is able to deliver 900mA current.
+
+properties:
+  compatible:
+    enum:
+      - silergy,sy7802
+
+  reg:
+    maxItems: 1
+
+  enable-gpios:
+    maxItems: 1
+    description: A connection to the 'EN' pin.
+
+  flash-gpios:
+    maxItems: 1
+    description: A connection to the 'FLEN' pin.
+
+  vin-supply:
+    description: Regulator providing power to the 'VIN' pin.
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^led@[0-1]$":
+    type: object
+    $ref: common.yaml#
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        description: Index of the LED.
+        minimum: 0
+        maximum: 1
+
+      led-sources:
+        minItems: 1
+        maxItems: 2
+        items:
+          minimum: 0
+          maximum: 1
+
+    required:
+      - reg
+      - led-sources
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+  - enable-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/leds/common.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        flash-led-controller@53 {
+            compatible = "silergy,sy7802";
+            reg = <0x53>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            enable-gpios = <&tlmm 16 GPIO_ACTIVE_HIGH>;
+
+            led@0 {
+                reg = <0>;
+                function = LED_FUNCTION_FLASH;
+                color = <LED_COLOR_ID_WHITE>;
+                led-sources = <0>, <1>;
+            };
+        };
+    };

-- 
2.45.2

[PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[André Apitzsch via B4 Relay]

From: André Apitzsch <git@apitzsch.eu>

The SY7802 is a current-regulated charge pump which can regulate two
current levels for Flash and Torch modes.

It is a high-current synchronous boost converter with 2-channel high
side current sources. Each channel is able to deliver 900mA current.

Signed-off-by: André Apitzsch <git@apitzsch.eu>
---
 drivers/leds/flash/Kconfig       |  11 +
 drivers/leds/flash/Makefile      |   1 +
 drivers/leds/flash/leds-sy7802.c | 542 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 554 insertions(+)

diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
index 809b6d98bb3e..f39f0bfe6eef 100644
--- a/drivers/leds/flash/Kconfig
+++ b/drivers/leds/flash/Kconfig
@@ -121,4 +121,15 @@ config LEDS_SGM3140
 	  This option enables support for the SGM3140 500mA Buck/Boost Charge
 	  Pump LED Driver.
 
+config LEDS_SY7802
+	tristate "LED support for the Silergy SY7802"
+	depends on I2C && OF
+	depends on GPIOLIB
+	select REGMAP_I2C
+	help
+	  This option enables support for the SY7802 flash LED controller.
+	  SY7802 includes torch and flash functions with programmable current.
+
+	  This driver can be built as a module, it will be called "leds-sy7802".
+
 endif # LEDS_CLASS_FLASH
diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
index 91d60a4b7952..48860eeced79 100644
--- a/drivers/leds/flash/Makefile
+++ b/drivers/leds/flash/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_LEDS_QCOM_FLASH)	+= leds-qcom-flash.o
 obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
 obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
 obj-$(CONFIG_LEDS_SGM3140)	+= leds-sgm3140.o
+obj-$(CONFIG_LEDS_SY7802)	+= leds-sy7802.o
diff --git a/drivers/leds/flash/leds-sy7802.c b/drivers/leds/flash/leds-sy7802.c
new file mode 100644
index 000000000000..c4bea55a62d0
--- /dev/null
+++ b/drivers/leds/flash/leds-sy7802.c
@@ -0,0 +1,542 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Silergy SY7802 flash LED driver with I2C interface
+ *
+ * Copyright 2024 André Apitzsch <git@apitzsch.eu>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/led-class-flash.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#define SY7802_MAX_LEDS 2
+#define SY7802_LED_JOINT 2
+
+#define SY7802_REG_ENABLE		0x10
+#define SY7802_REG_TORCH_BRIGHTNESS	0xa0
+#define SY7802_REG_FLASH_BRIGHTNESS	0xb0
+#define SY7802_REG_FLASH_DURATION	0xc0
+#define SY7802_REG_FLAGS		0xd0
+#define SY7802_REG_CONFIG_1		0xe0
+#define SY7802_REG_CONFIG_2		0xf0
+#define SY7802_REG_VIN_MONITOR		0x80
+#define SY7802_REG_LAST_FLASH		0x81
+#define SY7802_REG_VLED_MONITOR		0x30
+#define SY7802_REG_ADC_DELAY		0x31
+#define SY7802_REG_DEV_ID		0xff
+
+#define SY7802_MODE_OFF		0
+#define SY7802_MODE_TORCH	2
+#define SY7802_MODE_FLASH	3
+#define SY7802_MODE_MASK	GENMASK(1, 0)
+
+#define SY7802_LEDS_SHIFT	3
+#define SY7802_LEDS_MASK(_id)	(BIT(_id) << SY7802_LEDS_SHIFT)
+#define SY7802_LEDS_MASK_ALL	(SY7802_LEDS_MASK(0) | SY7802_LEDS_MASK(1))
+
+#define SY7802_TORCH_CURRENT_SHIFT	3
+#define SY7802_TORCH_CURRENT_MASK(_id) \
+	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
+#define SY7802_TORCH_CURRENT_MASK_ALL \
+	(SY7802_TORCH_CURRENT_MASK(0) | SY7802_TORCH_CURRENT_MASK(1))
+
+#define SY7802_FLASH_CURRENT_SHIFT	4
+#define SY7802_FLASH_CURRENT_MASK(_id) \
+	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
+#define SY7802_FLASH_CURRENT_MASK_ALL \
+	(SY7802_FLASH_CURRENT_MASK(0) | SY7802_FLASH_CURRENT_MASK(1))
+
+#define SY7802_TIMEOUT_DEFAULT_US	512000U
+#define SY7802_TIMEOUT_MIN_US		32000U
+#define SY7802_TIMEOUT_MAX_US		1024000U
+#define SY7802_TIMEOUT_STEPSIZE_US	32000U
+
+#define SY7802_TORCH_BRIGHTNESS_MAX 8
+
+#define SY7802_FLASH_BRIGHTNESS_DEFAULT	14
+#define SY7802_FLASH_BRIGHTNESS_MIN	0
+#define SY7802_FLASH_BRIGHTNESS_MAX	15
+#define SY7802_FLASH_BRIGHTNESS_STEP	1
+
+#define SY7802_FLAG_TIMEOUT			BIT(0)
+#define SY7802_FLAG_THERMAL_SHUTDOWN		BIT(1)
+#define SY7802_FLAG_LED_FAULT			BIT(2)
+#define SY7802_FLAG_TX1_INTERRUPT		BIT(3)
+#define SY7802_FLAG_TX2_INTERRUPT		BIT(4)
+#define SY7802_FLAG_LED_THERMAL_FAULT		BIT(5)
+#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW	BIT(6)
+#define SY7802_FLAG_INPUT_VOLTAGE_LOW		BIT(7)
+
+#define SY7802_CHIP_ID	0x51
+
+static const struct reg_default sy7802_regmap_defs[] = {
+	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
+	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
+	{ SY7802_REG_FLASH_BRIGHTNESS, SY7802_FLASH_BRIGHTNESS_DEFAULT |
+		SY7802_FLASH_BRIGHTNESS_DEFAULT << SY7802_FLASH_CURRENT_SHIFT },
+	{ SY7802_REG_FLASH_DURATION, 0x6f },
+	{ SY7802_REG_FLAGS, 0x0 },
+	{ SY7802_REG_CONFIG_1, 0x68 },
+	{ SY7802_REG_CONFIG_2, 0xf0 },
+};
+
+struct sy7802_led {
+	struct led_classdev_flash flash;
+	struct sy7802 *chip;
+	u8 led_id;
+};
+
+struct sy7802 {
+	struct device *dev;
+	struct regmap *regmap;
+	struct mutex mutex;
+
+	struct gpio_desc *enable_gpio;
+	struct regulator *vin_regulator;
+
+	unsigned int fled_strobe_used;
+	unsigned int fled_torch_used;
+	unsigned int leds_active;
+	int num_leds;
+	struct sy7802_led leds[] __counted_by(num_leds);
+};
+
+static int sy7802_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness brightness)
+{
+	struct sy7802_led *led = container_of(lcdev, struct sy7802_led, flash.led_cdev);
+	struct sy7802 *chip = led->chip;
+	u32 fled_torch_used_tmp;
+	u32 led_enable_mask;
+	u32 enable_mask;
+	u32 torch_mask;
+	u32 val;
+	int ret;
+
+	mutex_lock(&chip->mutex);
+
+	if (chip->fled_strobe_used) {
+		dev_warn(chip->dev, "Cannot set torch brightness whilst strobe is enabled\n");
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (brightness)
+		fled_torch_used_tmp = chip->fled_torch_used | BIT(led->led_id);
+	else
+		fled_torch_used_tmp = chip->fled_torch_used & ~BIT(led->led_id);
+
+	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
+			  SY7802_LEDS_MASK_ALL :
+			  SY7802_LEDS_MASK(led->led_id);
+
+	val = brightness ? led_enable_mask : SY7802_MODE_OFF;
+	if (fled_torch_used_tmp)
+		val |= SY7802_MODE_TORCH;
+
+	/* Disable torch to apply brightness */
+	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_MASK,
+				 SY7802_MODE_OFF);
+	if (ret)
+		goto unlock;
+
+	torch_mask = led->led_id == SY7802_LED_JOINT ?
+		     SY7802_TORCH_CURRENT_MASK_ALL :
+		     SY7802_TORCH_CURRENT_MASK(led->led_id);
+
+	/* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */
+	if (brightness)
+		brightness -= 1;
+
+	brightness |= (brightness << SY7802_TORCH_CURRENT_SHIFT);
+
+	ret = regmap_update_bits(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, torch_mask, brightness);
+	if (ret)
+		goto unlock;
+
+	enable_mask = SY7802_MODE_MASK | led_enable_mask;
+	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
+	if (ret)
+		goto unlock;
+
+	chip->fled_torch_used = fled_torch_used_tmp;
+
+unlock:
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+static int sy7802_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
+{
+	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
+	struct led_flash_setting *s = &fl_cdev->brightness;
+	u32 val = (brightness - s->min) / s->step;
+	struct sy7802 *chip = led->chip;
+	u32 flash_mask;
+	int ret;
+
+	val |= (val << SY7802_FLASH_CURRENT_SHIFT);
+	flash_mask = led->led_id == SY7802_LED_JOINT ?
+		     SY7802_FLASH_CURRENT_MASK_ALL :
+		     SY7802_FLASH_CURRENT_MASK(led->led_id);
+
+	mutex_lock(&chip->mutex);
+	ret = regmap_update_bits(chip->regmap, SY7802_REG_FLASH_BRIGHTNESS, flash_mask, val);
+	mutex_unlock(&chip->mutex);
+
+	return ret;
+}
+
+static int sy7802_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
+{
+	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
+	struct sy7802 *chip = led->chip;
+	u32 fled_strobe_used_tmp;
+	u32 led_enable_mask;
+	u32 enable_mask;
+	u32 val;
+	int ret;
+
+	mutex_lock(&chip->mutex);
+
+	if (chip->fled_torch_used) {
+		dev_warn(chip->dev, "Cannot set strobe brightness whilst torch is enabled\n");
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (state)
+		fled_strobe_used_tmp = chip->fled_strobe_used | BIT(led->led_id);
+	else
+		fled_strobe_used_tmp = chip->fled_strobe_used & ~BIT(led->led_id);
+
+	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
+			  SY7802_LEDS_MASK_ALL :
+			  SY7802_LEDS_MASK(led->led_id);
+
+	val = state ? led_enable_mask : SY7802_MODE_OFF;
+	if (fled_strobe_used_tmp)
+		val |= SY7802_MODE_FLASH;
+
+	enable_mask = SY7802_MODE_MASK | led_enable_mask;
+	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
+
+	if (ret)
+		goto unlock;
+
+	chip->fled_strobe_used = fled_strobe_used_tmp;
+
+unlock:
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+static int sy7802_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
+{
+	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
+	struct sy7802 *chip = led->chip;
+
+	mutex_lock(&chip->mutex);
+	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
+	mutex_unlock(&chip->mutex);
+
+	return 0;
+}
+
+static int sy7802_timeout_set(struct led_classdev_flash *fl_cdev,
+			      u32 timeout)
+{
+	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
+	struct led_flash_setting *s = &fl_cdev->timeout;
+	u32 val = (timeout - s->min) / s->step;
+	struct sy7802 *chip = led->chip;
+
+	return regmap_write(chip->regmap, SY7802_REG_FLASH_DURATION, val);
+}
+
+static int sy7802_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
+{
+	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
+	struct sy7802 *chip = led->chip;
+	u32 val, led_faults = 0;
+	int ret;
+
+	/* NOTE: reading register clears fault status */
+	ret = regmap_read(chip->regmap, SY7802_REG_FLAGS, &val);
+	if (ret)
+		return ret;
+
+	if (val & (SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW | SY7802_FLAG_INPUT_VOLTAGE_LOW))
+		led_faults |= LED_FAULT_INPUT_VOLTAGE;
+
+	if (val & SY7802_FLAG_THERMAL_SHUTDOWN)
+		led_faults |= LED_FAULT_OVER_TEMPERATURE;
+
+	if (val & SY7802_FLAG_TIMEOUT)
+		led_faults |= LED_FAULT_TIMEOUT;
+
+	*fault = led_faults;
+	return 0;
+}
+
+static const struct led_flash_ops sy7802_flash_ops = {
+	.flash_brightness_set = sy7802_flash_brightness_set,
+	.strobe_set = sy7802_strobe_set,
+	.strobe_get = sy7802_strobe_get,
+	.timeout_set = sy7802_timeout_set,
+	.fault_get = sy7802_fault_get,
+};
+
+static void sy7802_init_flash_brightness(struct led_classdev_flash *fl_cdev)
+{
+	struct led_flash_setting *s;
+
+	/* Init flash brightness setting */
+	s = &fl_cdev->brightness;
+	s->min = SY7802_FLASH_BRIGHTNESS_MIN;
+	s->max = SY7802_FLASH_BRIGHTNESS_MAX;
+	s->step = SY7802_FLASH_BRIGHTNESS_STEP;
+	s->val = SY7802_FLASH_BRIGHTNESS_DEFAULT;
+}
+
+static void sy7802_init_flash_timeout(struct led_classdev_flash *fl_cdev)
+{
+	struct led_flash_setting *s;
+
+	/* Init flash timeout setting */
+	s = &fl_cdev->timeout;
+	s->min = SY7802_TIMEOUT_MIN_US;
+	s->max = SY7802_TIMEOUT_MAX_US;
+	s->step = SY7802_TIMEOUT_STEPSIZE_US;
+	s->val = SY7802_TIMEOUT_DEFAULT_US;
+}
+
+static int sy7802_led_register(struct device *dev, struct sy7802_led *led,
+			       struct device_node *np)
+{
+	struct led_init_data init_data = {};
+	int ret;
+
+	init_data.fwnode = of_fwnode_handle(np);
+
+	ret = devm_led_classdev_flash_register_ext(dev, &led->flash, &init_data);
+	if (ret) {
+		dev_err(dev, "Couldn't register flash %d\n", led->led_id);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int sy7802_init_flash_properties(struct device *dev, struct sy7802_led *led,
+					struct device_node *np)
+{
+	struct led_classdev_flash *flash = &led->flash;
+	struct led_classdev *lcdev = &flash->led_cdev;
+	u32 sources[SY7802_MAX_LEDS];
+	int i, num, ret;
+
+	num = of_property_count_u32_elems(np, "led-sources");
+	if (num < 1) {
+		dev_err(dev, "Not specified or wrong number of led-sources\n");
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32_array(np, "led-sources", sources, num);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < num; i++) {
+		if (sources[i] >= SY7802_MAX_LEDS)
+			return -EINVAL;
+		if (led->chip->leds_active & BIT(sources[i]))
+			return -EINVAL;
+		led->chip->leds_active |= BIT(sources[i]);
+	}
+
+	/* If both channels are specified in 'led-sources', joint flash output mode is used */
+	led->led_id = num == 2 ? SY7802_LED_JOINT : sources[0];
+
+	lcdev->max_brightness = SY7802_TORCH_BRIGHTNESS_MAX;
+	lcdev->brightness_set_blocking = sy7802_torch_brightness_set;
+	lcdev->flags |= LED_DEV_CAP_FLASH;
+
+	flash->ops = &sy7802_flash_ops;
+
+	sy7802_init_flash_brightness(flash);
+	sy7802_init_flash_timeout(flash);
+
+	return 0;
+}
+
+static int sy7802_chip_check(struct sy7802 *chip)
+{
+	struct device *dev = chip->dev;
+	u32 chipid;
+	int ret;
+
+	ret = regmap_read(chip->regmap, SY7802_REG_DEV_ID, &chipid);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
+
+	if (chipid != SY7802_CHIP_ID)
+		return dev_err_probe(dev, -ENODEV, "Unsupported chip detected: %x\n", chipid);
+
+	return 0;
+}
+
+static void sy7802_enable(struct sy7802 *chip)
+{
+	gpiod_set_value_cansleep(chip->enable_gpio, 1);
+	usleep_range(200, 300);
+}
+
+static void sy7802_disable(struct sy7802 *chip)
+{
+	gpiod_set_value_cansleep(chip->enable_gpio, 0);
+}
+
+static int sy7802_probe_dt(struct sy7802 *chip)
+{
+	struct device_node *np = dev_of_node(chip->dev);
+	int child_num;
+	int ret;
+
+	regmap_write(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_OFF);
+	regmap_write(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, LED_OFF);
+
+	child_num = 0;
+	for_each_available_child_of_node_scoped(np, child) {
+		struct sy7802_led *led = chip->leds + child_num;
+
+		led->chip = chip;
+		led->led_id = child_num;
+
+		ret = sy7802_init_flash_properties(chip->dev, led, child);
+		if (ret)
+			return ret;
+
+		ret = sy7802_led_register(chip->dev, led, child);
+		if (ret)
+			return ret;
+
+		child_num++;
+	}
+	return 0;
+}
+
+static void sy7802_chip_disable_action(void *data)
+{
+	struct sy7802 *chip = data;
+
+	sy7802_disable(chip);
+}
+
+static void sy7802_regulator_disable_action(void *data)
+{
+	struct sy7802 *chip = data;
+
+	regulator_disable(chip->vin_regulator);
+}
+
+static const struct regmap_config sy7802_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xff,
+	.cache_type = REGCACHE_MAPLE,
+	.reg_defaults = sy7802_regmap_defs,
+	.num_reg_defaults = ARRAY_SIZE(sy7802_regmap_defs),
+};
+
+static int sy7802_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct sy7802 *chip;
+	size_t count;
+	int ret;
+
+	count = device_get_child_node_count(dev);
+	if (!count || count > SY7802_MAX_LEDS)
+		return dev_err_probe(dev, -EINVAL, "Invalid amount of LED nodes %zu\n", count);
+
+	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->num_leds = count;
+
+	chip->dev = dev;
+	i2c_set_clientdata(client, chip);
+
+	chip->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+	ret = PTR_ERR_OR_ZERO(chip->enable_gpio);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to request enable gpio\n");
+
+	chip->vin_regulator = devm_regulator_get(dev, "vin");
+	ret = PTR_ERR_OR_ZERO(chip->vin_regulator);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to request regulator\n");
+
+	ret = regulator_enable(chip->vin_regulator);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable regulator\n");
+
+	ret = devm_add_action_or_reset(dev, sy7802_regulator_disable_action, chip);
+	if (ret)
+		return ret;
+
+	ret = devm_mutex_init(dev, &chip->mutex);
+	if (ret)
+		return ret;
+
+	mutex_lock(&chip->mutex);
+
+	chip->regmap = devm_regmap_init_i2c(client, &sy7802_regmap_config);
+	if (IS_ERR(chip->regmap)) {
+		ret = PTR_ERR(chip->regmap);
+		dev_err_probe(dev, ret, "Failed to allocate register map\n");
+		goto error;
+	}
+
+	ret = sy7802_probe_dt(chip);
+	if (ret < 0)
+		goto error;
+
+	sy7802_enable(chip);
+
+	ret = devm_add_action_or_reset(dev, sy7802_chip_disable_action, chip);
+	if (ret)
+		goto error;
+
+	ret = sy7802_chip_check(chip);
+
+error:
+	mutex_unlock(&chip->mutex);
+	return ret;
+}
+
+static const struct of_device_id __maybe_unused sy7802_leds_match[] = {
+	{ .compatible = "silergy,sy7802", },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, sy7802_leds_match);
+
+static struct i2c_driver sy7802_driver = {
+	.driver = {
+		.name = "sy7802",
+		.of_match_table = of_match_ptr(sy7802_leds_match),
+	},
+	.probe = sy7802_probe,
+};
+
+module_i2c_driver(sy7802_driver);
+
+MODULE_AUTHOR("André Apitzsch <git@apitzsch.eu>");
+MODULE_DESCRIPTION("Silergy SY7802 flash LED driver");
+MODULE_LICENSE("GPL");

-- 
2.45.2

Re: [PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Markus Elfring]

> The SY7802 is a current-regulated charge pump which can regulate two
> current levels for Flash and Torch modes.
>
> It is a high-current synchronous boost converter with 2-channel high
> side current sources. Each channel is able to deliver 900mA current.

Would you like to improve such a change description with imperative wordings?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.10-rc3#n94


…
> +++ b/drivers/leds/flash/leds-sy7802.c
> @@ -0,0 +1,542 @@
…
> +static int sy7802_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> +{
…
> +	mutex_lock(&chip->mutex);
> +	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
> +	mutex_unlock(&chip->mutex);
> +
> +	return 0;
> +}
…

Would you become interested to apply a statement like “guard(mutex)(&chip->mutex);”?
https://elixir.bootlin.com/linux/v6.10-rc3/source/include/linux/mutex.h#L196

Regards,
Markus

Re: [PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Pavel Machek]

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On Sun 2024-06-16 20:55:41, Markus Elfring wrote:
> > The SY7802 is a current-regulated charge pump which can regulate two
> > current levels for Flash and Torch modes.
> >
> > It is a high-current synchronous boost converter with 2-channel high
> > side current sources. Each channel is able to deliver 900mA current.
> 
> Would you like to improve such a change description with imperative wordings?
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.10-rc3#n94
> 

Feel free to ignore this.

> …
> > +++ b/drivers/leds/flash/leds-sy7802.c
> > @@ -0,0 +1,542 @@
> …
> > +static int sy7802_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> > +{
> …
> > +	mutex_lock(&chip->mutex);
> > +	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
> > +	mutex_unlock(&chip->mutex);
> > +
> > +	return 0;
> > +}
> …
> 
> Would you become interested to apply a statement like “guard(mutex)(&chip->mutex);”?
> https://elixir.bootlin.com/linux/v6.10-rc3/source/include/linux/mutex.h#L196

This does not look like real improvement for code this trivial.

BR,
								Pavel
-- 
People of Russia, stop Putin before his war on Ukraine escalates.

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Re: [v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Markus Elfring]

>> Would you become interested to apply a statement like “guard(mutex)(&chip->mutex);”?
>> https://elixir.bootlin.com/linux/v6.10-rc3/source/include/linux/mutex.h#L196
>
> This does not look like real improvement for code this trivial.

Various source code places can be updated also according to referenced
programming interfaces.
https://elixir.bootlin.com/linux/v6.10-rc4/source/include/linux/cleanup.h#L8

Will corresponding collateral evolution become better supported?

Regards,
Markus

Re: [v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Dmitry Baryshkov]

On Mon, Jun 17, 2024 at 12:18:11PM GMT, Markus Elfring wrote:
> >> Would you become interested to apply a statement like “guard(mutex)(&chip->mutex);”?
> >> https://elixir.bootlin.com/linux/v6.10-rc3/source/include/linux/mutex.h#L196
> >
> > This does not look like real improvement for code this trivial.
> 
> Various source code places can be updated also according to referenced
> programming interfaces.
> https://elixir.bootlin.com/linux/v6.10-rc4/source/include/linux/cleanup.h#L8
> 
> Will corresponding collateral evolution become better supported?

Plesae stop this. cleanup.h might be a nice thing, but it should not be
used to make code less obvious or worse.

-- 
With best wishes
Dmitry

Re: [v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Markus Elfring]

>> Various source code places can be updated also according to referenced
>> programming interfaces.
>> https://elixir.bootlin.com/linux/v6.10-rc4/source/include/linux/cleanup.h#L8
>>
>> Will corresponding collateral evolution become better supported?
>
> Plesae stop this. cleanup.h might be a nice thing, but it should not be
> used to make code less obvious or worse.

These APIs were added to improve several software components,
weren't they?

Regards,
Markus

Re: [PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Lee Jones]

On Sun, 16 Jun 2024, André Apitzsch via B4 Relay wrote:

> From: André Apitzsch <git@apitzsch.eu>
> 
> The SY7802 is a current-regulated charge pump which can regulate two
> current levels for Flash and Torch modes.
> 
> It is a high-current synchronous boost converter with 2-channel high
> side current sources. Each channel is able to deliver 900mA current.
> 
> Signed-off-by: André Apitzsch <git@apitzsch.eu>
> ---
>  drivers/leds/flash/Kconfig       |  11 +
>  drivers/leds/flash/Makefile      |   1 +
>  drivers/leds/flash/leds-sy7802.c | 542 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 554 insertions(+)

Generally very nice.

Just a couple of teensy nits to fix then add my and resubmit please.

Acked-by: Lee Jones <lee@kernel.org>

> diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
> index 809b6d98bb3e..f39f0bfe6eef 100644
> --- a/drivers/leds/flash/Kconfig
> +++ b/drivers/leds/flash/Kconfig
> @@ -121,4 +121,15 @@ config LEDS_SGM3140
>  	  This option enables support for the SGM3140 500mA Buck/Boost Charge
>  	  Pump LED Driver.
>  
> +config LEDS_SY7802
> +	tristate "LED support for the Silergy SY7802"
> +	depends on I2C && OF
> +	depends on GPIOLIB
> +	select REGMAP_I2C
> +	help
> +	  This option enables support for the SY7802 flash LED controller.
> +	  SY7802 includes torch and flash functions with programmable current.
> +
> +	  This driver can be built as a module, it will be called "leds-sy7802".
> +
>  endif # LEDS_CLASS_FLASH
> diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
> index 91d60a4b7952..48860eeced79 100644
> --- a/drivers/leds/flash/Makefile
> +++ b/drivers/leds/flash/Makefile
> @@ -11,3 +11,4 @@ obj-$(CONFIG_LEDS_QCOM_FLASH)	+= leds-qcom-flash.o
>  obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
>  obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
>  obj-$(CONFIG_LEDS_SGM3140)	+= leds-sgm3140.o
> +obj-$(CONFIG_LEDS_SY7802)	+= leds-sy7802.o
> diff --git a/drivers/leds/flash/leds-sy7802.c b/drivers/leds/flash/leds-sy7802.c
> new file mode 100644
> index 000000000000..c4bea55a62d0
> --- /dev/null
> +++ b/drivers/leds/flash/leds-sy7802.c
> @@ -0,0 +1,542 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Silergy SY7802 flash LED driver with I2C interface

"an I2C interface"

Or

"I2C interfaces"

> + * Copyright 2024 André Apitzsch <git@apitzsch.eu>
> + */
> +
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/kernel.h>
> +#include <linux/led-class-flash.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +
> +#define SY7802_MAX_LEDS 2
> +#define SY7802_LED_JOINT 2
> +
> +#define SY7802_REG_ENABLE		0x10
> +#define SY7802_REG_TORCH_BRIGHTNESS	0xa0
> +#define SY7802_REG_FLASH_BRIGHTNESS	0xb0
> +#define SY7802_REG_FLASH_DURATION	0xc0
> +#define SY7802_REG_FLAGS		0xd0
> +#define SY7802_REG_CONFIG_1		0xe0
> +#define SY7802_REG_CONFIG_2		0xf0
> +#define SY7802_REG_VIN_MONITOR		0x80
> +#define SY7802_REG_LAST_FLASH		0x81
> +#define SY7802_REG_VLED_MONITOR		0x30
> +#define SY7802_REG_ADC_DELAY		0x31
> +#define SY7802_REG_DEV_ID		0xff
> +
> +#define SY7802_MODE_OFF		0
> +#define SY7802_MODE_TORCH	2
> +#define SY7802_MODE_FLASH	3
> +#define SY7802_MODE_MASK	GENMASK(1, 0)
> +
> +#define SY7802_LEDS_SHIFT	3
> +#define SY7802_LEDS_MASK(_id)	(BIT(_id) << SY7802_LEDS_SHIFT)
> +#define SY7802_LEDS_MASK_ALL	(SY7802_LEDS_MASK(0) | SY7802_LEDS_MASK(1))
> +
> +#define SY7802_TORCH_CURRENT_SHIFT	3
> +#define SY7802_TORCH_CURRENT_MASK(_id) \
> +	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
> +#define SY7802_TORCH_CURRENT_MASK_ALL \
> +	(SY7802_TORCH_CURRENT_MASK(0) | SY7802_TORCH_CURRENT_MASK(1))
> +
> +#define SY7802_FLASH_CURRENT_SHIFT	4
> +#define SY7802_FLASH_CURRENT_MASK(_id) \
> +	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
> +#define SY7802_FLASH_CURRENT_MASK_ALL \
> +	(SY7802_FLASH_CURRENT_MASK(0) | SY7802_FLASH_CURRENT_MASK(1))
> +
> +#define SY7802_TIMEOUT_DEFAULT_US	512000U
> +#define SY7802_TIMEOUT_MIN_US		32000U
> +#define SY7802_TIMEOUT_MAX_US		1024000U
> +#define SY7802_TIMEOUT_STEPSIZE_US	32000U
> +
> +#define SY7802_TORCH_BRIGHTNESS_MAX 8
> +
> +#define SY7802_FLASH_BRIGHTNESS_DEFAULT	14
> +#define SY7802_FLASH_BRIGHTNESS_MIN	0
> +#define SY7802_FLASH_BRIGHTNESS_MAX	15
> +#define SY7802_FLASH_BRIGHTNESS_STEP	1
> +
> +#define SY7802_FLAG_TIMEOUT			BIT(0)
> +#define SY7802_FLAG_THERMAL_SHUTDOWN		BIT(1)
> +#define SY7802_FLAG_LED_FAULT			BIT(2)
> +#define SY7802_FLAG_TX1_INTERRUPT		BIT(3)
> +#define SY7802_FLAG_TX2_INTERRUPT		BIT(4)
> +#define SY7802_FLAG_LED_THERMAL_FAULT		BIT(5)
> +#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW	BIT(6)
> +#define SY7802_FLAG_INPUT_VOLTAGE_LOW		BIT(7)
> +
> +#define SY7802_CHIP_ID	0x51
> +
> +static const struct reg_default sy7802_regmap_defs[] = {
> +	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
> +	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
> +	{ SY7802_REG_FLASH_BRIGHTNESS, SY7802_FLASH_BRIGHTNESS_DEFAULT |
> +		SY7802_FLASH_BRIGHTNESS_DEFAULT << SY7802_FLASH_CURRENT_SHIFT },
> +	{ SY7802_REG_FLASH_DURATION, 0x6f },
> +	{ SY7802_REG_FLAGS, 0x0 },
> +	{ SY7802_REG_CONFIG_1, 0x68 },
> +	{ SY7802_REG_CONFIG_2, 0xf0 },

Not your fault, but this interface is frustrating since we have no idea
what these register values mean.  IMHO, they should be defined and ORed
together in some human readable way.

I say that it's not your fault because I see that this is the most
common usage.

> +};
> +
> +struct sy7802_led {
> +	struct led_classdev_flash flash;
> +	struct sy7802 *chip;
> +	u8 led_id;
> +};
> +
> +struct sy7802 {
> +	struct device *dev;
> +	struct regmap *regmap;
> +	struct mutex mutex;
> +
> +	struct gpio_desc *enable_gpio;
> +	struct regulator *vin_regulator;
> +
> +	unsigned int fled_strobe_used;
> +	unsigned int fled_torch_used;
> +	unsigned int leds_active;
> +	int num_leds;
> +	struct sy7802_led leds[] __counted_by(num_leds);
> +};
> +
> +static int sy7802_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness brightness)
> +{
> +	struct sy7802_led *led = container_of(lcdev, struct sy7802_led, flash.led_cdev);
> +	struct sy7802 *chip = led->chip;
> +	u32 fled_torch_used_tmp;
> +	u32 led_enable_mask;
> +	u32 enable_mask;
> +	u32 torch_mask;
> +	u32 val;
> +	int ret;
> +
> +	mutex_lock(&chip->mutex);
> +
> +	if (chip->fled_strobe_used) {
> +		dev_warn(chip->dev, "Cannot set torch brightness whilst strobe is enabled\n");
> +		ret = -EBUSY;
> +		goto unlock;
> +	}
> +
> +	if (brightness)
> +		fled_torch_used_tmp = chip->fled_torch_used | BIT(led->led_id);
> +	else
> +		fled_torch_used_tmp = chip->fled_torch_used & ~BIT(led->led_id);
> +
> +	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
> +			  SY7802_LEDS_MASK_ALL :
> +			  SY7802_LEDS_MASK(led->led_id);
> +
> +	val = brightness ? led_enable_mask : SY7802_MODE_OFF;
> +	if (fled_torch_used_tmp)
> +		val |= SY7802_MODE_TORCH;
> +
> +	/* Disable torch to apply brightness */
> +	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_MASK,
> +				 SY7802_MODE_OFF);
> +	if (ret)
> +		goto unlock;
> +
> +	torch_mask = led->led_id == SY7802_LED_JOINT ?
> +		     SY7802_TORCH_CURRENT_MASK_ALL :
> +		     SY7802_TORCH_CURRENT_MASK(led->led_id);
> +
> +	/* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */
> +	if (brightness)
> +		brightness -= 1;
> +
> +	brightness |= (brightness << SY7802_TORCH_CURRENT_SHIFT);
> +
> +	ret = regmap_update_bits(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, torch_mask, brightness);
> +	if (ret)
> +		goto unlock;
> +
> +	enable_mask = SY7802_MODE_MASK | led_enable_mask;
> +	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
> +	if (ret)
> +		goto unlock;
> +
> +	chip->fled_torch_used = fled_torch_used_tmp;
> +
> +unlock:
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +}
> +
> +static int sy7802_flash_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
> +{
> +	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
> +	struct led_flash_setting *s = &fl_cdev->brightness;
> +	u32 val = (brightness - s->min) / s->step;
> +	struct sy7802 *chip = led->chip;
> +	u32 flash_mask;
> +	int ret;
> +
> +	val |= (val << SY7802_FLASH_CURRENT_SHIFT);
> +	flash_mask = led->led_id == SY7802_LED_JOINT ?
> +		     SY7802_FLASH_CURRENT_MASK_ALL :
> +		     SY7802_FLASH_CURRENT_MASK(led->led_id);
> +
> +	mutex_lock(&chip->mutex);
> +	ret = regmap_update_bits(chip->regmap, SY7802_REG_FLASH_BRIGHTNESS, flash_mask, val);
> +	mutex_unlock(&chip->mutex);
> +
> +	return ret;
> +}
> +
> +static int sy7802_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
> +{
> +	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
> +	struct sy7802 *chip = led->chip;
> +	u32 fled_strobe_used_tmp;
> +	u32 led_enable_mask;
> +	u32 enable_mask;
> +	u32 val;
> +	int ret;
> +
> +	mutex_lock(&chip->mutex);
> +
> +	if (chip->fled_torch_used) {
> +		dev_warn(chip->dev, "Cannot set strobe brightness whilst torch is enabled\n");
> +		ret = -EBUSY;
> +		goto unlock;
> +	}
> +
> +	if (state)
> +		fled_strobe_used_tmp = chip->fled_strobe_used | BIT(led->led_id);
> +	else
> +		fled_strobe_used_tmp = chip->fled_strobe_used & ~BIT(led->led_id);
> +
> +	led_enable_mask = led->led_id == SY7802_LED_JOINT ?
> +			  SY7802_LEDS_MASK_ALL :
> +			  SY7802_LEDS_MASK(led->led_id);
> +
> +	val = state ? led_enable_mask : SY7802_MODE_OFF;
> +	if (fled_strobe_used_tmp)
> +		val |= SY7802_MODE_FLASH;
> +
> +	enable_mask = SY7802_MODE_MASK | led_enable_mask;
> +	ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
> +
> +	if (ret)
> +		goto unlock;
> +
> +	chip->fled_strobe_used = fled_strobe_used_tmp;
> +
> +unlock:
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +}
> +
> +static int sy7802_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> +{
> +	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
> +	struct sy7802 *chip = led->chip;
> +
> +	mutex_lock(&chip->mutex);
> +	*state = !!(chip->fled_strobe_used & BIT(led->led_id));
> +	mutex_unlock(&chip->mutex);
> +
> +	return 0;
> +}
> +
> +static int sy7802_timeout_set(struct led_classdev_flash *fl_cdev,
> +			      u32 timeout)

Nit: Unwrap.

> +{
> +	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
> +	struct led_flash_setting *s = &fl_cdev->timeout;
> +	u32 val = (timeout - s->min) / s->step;
> +	struct sy7802 *chip = led->chip;
> +
> +	return regmap_write(chip->regmap, SY7802_REG_FLASH_DURATION, val);
> +}
> +
> +static int sy7802_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
> +{
> +	struct sy7802_led *led = container_of(fl_cdev, struct sy7802_led, flash);
> +	struct sy7802 *chip = led->chip;
> +	u32 val, led_faults = 0;
> +	int ret;
> +
> +	/* NOTE: reading register clears fault status */
> +	ret = regmap_read(chip->regmap, SY7802_REG_FLAGS, &val);
> +	if (ret)
> +		return ret;
> +
> +	if (val & (SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW | SY7802_FLAG_INPUT_VOLTAGE_LOW))
> +		led_faults |= LED_FAULT_INPUT_VOLTAGE;
> +
> +	if (val & SY7802_FLAG_THERMAL_SHUTDOWN)
> +		led_faults |= LED_FAULT_OVER_TEMPERATURE;
> +
> +	if (val & SY7802_FLAG_TIMEOUT)
> +		led_faults |= LED_FAULT_TIMEOUT;
> +
> +	*fault = led_faults;
> +	return 0;
> +}
> +
> +static const struct led_flash_ops sy7802_flash_ops = {
> +	.flash_brightness_set = sy7802_flash_brightness_set,
> +	.strobe_set = sy7802_strobe_set,
> +	.strobe_get = sy7802_strobe_get,
> +	.timeout_set = sy7802_timeout_set,
> +	.fault_get = sy7802_fault_get,
> +};
> +
> +static void sy7802_init_flash_brightness(struct led_classdev_flash *fl_cdev)
> +{
> +	struct led_flash_setting *s;
> +
> +	/* Init flash brightness setting */
> +	s = &fl_cdev->brightness;
> +	s->min = SY7802_FLASH_BRIGHTNESS_MIN;
> +	s->max = SY7802_FLASH_BRIGHTNESS_MAX;
> +	s->step = SY7802_FLASH_BRIGHTNESS_STEP;
> +	s->val = SY7802_FLASH_BRIGHTNESS_DEFAULT;
> +}
> +
> +static void sy7802_init_flash_timeout(struct led_classdev_flash *fl_cdev)
> +{
> +	struct led_flash_setting *s;
> +
> +	/* Init flash timeout setting */
> +	s = &fl_cdev->timeout;
> +	s->min = SY7802_TIMEOUT_MIN_US;
> +	s->max = SY7802_TIMEOUT_MAX_US;
> +	s->step = SY7802_TIMEOUT_STEPSIZE_US;
> +	s->val = SY7802_TIMEOUT_DEFAULT_US;
> +}
> +
> +static int sy7802_led_register(struct device *dev, struct sy7802_led *led,
> +			       struct device_node *np)
> +{
> +	struct led_init_data init_data = {};
> +	int ret;
> +
> +	init_data.fwnode = of_fwnode_handle(np);
> +
> +	ret = devm_led_classdev_flash_register_ext(dev, &led->flash, &init_data);
> +	if (ret) {
> +		dev_err(dev, "Couldn't register flash %d\n", led->led_id);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int sy7802_init_flash_properties(struct device *dev, struct sy7802_led *led,
> +					struct device_node *np)
> +{
> +	struct led_classdev_flash *flash = &led->flash;
> +	struct led_classdev *lcdev = &flash->led_cdev;
> +	u32 sources[SY7802_MAX_LEDS];
> +	int i, num, ret;
> +
> +	num = of_property_count_u32_elems(np, "led-sources");
> +	if (num < 1) {
> +		dev_err(dev, "Not specified or wrong number of led-sources\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_array(np, "led-sources", sources, num);
> +	if (ret)
> +		return ret;
> +
> +	for (i = 0; i < num; i++) {
> +		if (sources[i] >= SY7802_MAX_LEDS)
> +			return -EINVAL;
> +		if (led->chip->leds_active & BIT(sources[i]))
> +			return -EINVAL;
> +		led->chip->leds_active |= BIT(sources[i]);
> +	}
> +
> +	/* If both channels are specified in 'led-sources', joint flash output mode is used */
> +	led->led_id = num == 2 ? SY7802_LED_JOINT : sources[0];
> +
> +	lcdev->max_brightness = SY7802_TORCH_BRIGHTNESS_MAX;
> +	lcdev->brightness_set_blocking = sy7802_torch_brightness_set;
> +	lcdev->flags |= LED_DEV_CAP_FLASH;
> +
> +	flash->ops = &sy7802_flash_ops;
> +
> +	sy7802_init_flash_brightness(flash);
> +	sy7802_init_flash_timeout(flash);
> +
> +	return 0;
> +}
> +
> +static int sy7802_chip_check(struct sy7802 *chip)
> +{
> +	struct device *dev = chip->dev;
> +	u32 chipid;
> +	int ret;
> +
> +	ret = regmap_read(chip->regmap, SY7802_REG_DEV_ID, &chipid);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to read chip ID\n");
> +
> +	if (chipid != SY7802_CHIP_ID)
> +		return dev_err_probe(dev, -ENODEV, "Unsupported chip detected: %x\n", chipid);
> +
> +	return 0;
> +}
> +
> +static void sy7802_enable(struct sy7802 *chip)
> +{
> +	gpiod_set_value_cansleep(chip->enable_gpio, 1);
> +	usleep_range(200, 300);
> +}
> +
> +static void sy7802_disable(struct sy7802 *chip)
> +{
> +	gpiod_set_value_cansleep(chip->enable_gpio, 0);
> +}
> +
> +static int sy7802_probe_dt(struct sy7802 *chip)
> +{
> +	struct device_node *np = dev_of_node(chip->dev);
> +	int child_num;
> +	int ret;
> +
> +	regmap_write(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_OFF);
> +	regmap_write(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, LED_OFF);
> +
> +	child_num = 0;
> +	for_each_available_child_of_node_scoped(np, child) {
> +		struct sy7802_led *led = chip->leds + child_num;
> +
> +		led->chip = chip;
> +		led->led_id = child_num;
> +
> +		ret = sy7802_init_flash_properties(chip->dev, led, child);
> +		if (ret)
> +			return ret;
> +
> +		ret = sy7802_led_register(chip->dev, led, child);
> +		if (ret)
> +			return ret;
> +
> +		child_num++;
> +	}
> +	return 0;
> +}
> +
> +static void sy7802_chip_disable_action(void *data)
> +{
> +	struct sy7802 *chip = data;
> +
> +	sy7802_disable(chip);
> +}
> +
> +static void sy7802_regulator_disable_action(void *data)
> +{
> +	struct sy7802 *chip = data;
> +
> +	regulator_disable(chip->vin_regulator);
> +}
> +
> +static const struct regmap_config sy7802_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = 0xff,
> +	.cache_type = REGCACHE_MAPLE,
> +	.reg_defaults = sy7802_regmap_defs,
> +	.num_reg_defaults = ARRAY_SIZE(sy7802_regmap_defs),
> +};
> +
> +static int sy7802_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct sy7802 *chip;
> +	size_t count;
> +	int ret;
> +
> +	count = device_get_child_node_count(dev);
> +	if (!count || count > SY7802_MAX_LEDS)
> +		return dev_err_probe(dev, -EINVAL, "Invalid amount of LED nodes %zu\n", count);
> +
> +	chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
> +	if (!chip)
> +		return -ENOMEM;
> +
> +	chip->num_leds = count;
> +
> +	chip->dev = dev;
> +	i2c_set_clientdata(client, chip);
> +
> +	chip->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
> +	ret = PTR_ERR_OR_ZERO(chip->enable_gpio);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to request enable gpio\n");
> +
> +	chip->vin_regulator = devm_regulator_get(dev, "vin");
> +	ret = PTR_ERR_OR_ZERO(chip->vin_regulator);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to request regulator\n");
> +
> +	ret = regulator_enable(chip->vin_regulator);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to enable regulator\n");
> +
> +	ret = devm_add_action_or_reset(dev, sy7802_regulator_disable_action, chip);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_mutex_init(dev, &chip->mutex);
> +	if (ret)
> +		return ret;
> +
> +	mutex_lock(&chip->mutex);
> +
> +	chip->regmap = devm_regmap_init_i2c(client, &sy7802_regmap_config);
> +	if (IS_ERR(chip->regmap)) {
> +		ret = PTR_ERR(chip->regmap);
> +		dev_err_probe(dev, ret, "Failed to allocate register map\n");
> +		goto error;
> +	}
> +
> +	ret = sy7802_probe_dt(chip);
> +	if (ret < 0)
> +		goto error;
> +
> +	sy7802_enable(chip);
> +
> +	ret = devm_add_action_or_reset(dev, sy7802_chip_disable_action, chip);
> +	if (ret)
> +		goto error;
> +
> +	ret = sy7802_chip_check(chip);
> +
> +error:
> +	mutex_unlock(&chip->mutex);
> +	return ret;
> +}
> +
> +static const struct of_device_id __maybe_unused sy7802_leds_match[] = {
> +	{ .compatible = "silergy,sy7802", },
> +	{}
> +};
> +

Remove this line.

> +MODULE_DEVICE_TABLE(of, sy7802_leds_match);
> +
> +static struct i2c_driver sy7802_driver = {
> +	.driver = {
> +		.name = "sy7802",
> +		.of_match_table = of_match_ptr(sy7802_leds_match),
> +	},
> +	.probe = sy7802_probe,
> +};
> +

Remove this line.

> +module_i2c_driver(sy7802_driver);
> +
> +MODULE_AUTHOR("André Apitzsch <git@apitzsch.eu>");
> +MODULE_DESCRIPTION("Silergy SY7802 flash LED driver");
> +MODULE_LICENSE("GPL");
> 
> -- 
> 2.45.2
> 
> 

-- 
Lee Jones [李琼斯]

Re: [PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[André Apitzsch]

Hello Lee,

Am Freitag, dem 21.06.2024 um 11:26 +0100 schrieb Lee Jones:
> On Sun, 16 Jun 2024, André Apitzsch via B4 Relay wrote:
> 
> > From: André Apitzsch <git@apitzsch.eu>
> > 
> > The SY7802 is a current-regulated charge pump which can regulate
> > two
> > current levels for Flash and Torch modes.
> > 
> > It is a high-current synchronous boost converter with 2-channel
> > high
> > side current sources. Each channel is able to deliver 900mA
> > current.
> > 
> > Signed-off-by: André Apitzsch <git@apitzsch.eu>
> > ---
> >  drivers/leds/flash/Kconfig       |  11 +
> >  drivers/leds/flash/Makefile      |   1 +
> >  drivers/leds/flash/leds-sy7802.c | 542
> > +++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 554 insertions(+)
> 
> Generally very nice.
> 
> Just a couple of teensy nits to fix then add my and resubmit please.
> 
> Acked-by: Lee Jones <lee@kernel.org>
> 
> > [...]
> > diff --git a/drivers/leds/flash/leds-sy7802.c
> > b/drivers/leds/flash/leds-sy7802.c
> > new file mode 100644
> > index 000000000000..c4bea55a62d0
> > --- /dev/null
> > +++ b/drivers/leds/flash/leds-sy7802.c
> > @@ -0,0 +1,542 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/*
> > + * Silergy SY7802 flash LED driver with I2C interface
> 
> "an I2C interface"
> 
> Or
> 
> "I2C interfaces"
> 
> > + * Copyright 2024 André Apitzsch <git@apitzsch.eu>
> > + */
> > +
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/i2c.h>
> > +#include <linux/kernel.h>
> > +#include <linux/led-class-flash.h>
> > +#include <linux/module.h>
> > +#include <linux/mutex.h>
> > +#include <linux/regmap.h>
> > +#include <linux/regulator/consumer.h>
> > +
> > +#define SY7802_MAX_LEDS 2
> > +#define SY7802_LED_JOINT 2
> > +
> > +#define SY7802_REG_ENABLE		0x10
> > +#define SY7802_REG_TORCH_BRIGHTNESS	0xa0
> > +#define SY7802_REG_FLASH_BRIGHTNESS	0xb0
> > +#define SY7802_REG_FLASH_DURATION	0xc0
> > +#define SY7802_REG_FLAGS		0xd0
> > +#define SY7802_REG_CONFIG_1		0xe0
> > +#define SY7802_REG_CONFIG_2		0xf0
> > +#define SY7802_REG_VIN_MONITOR		0x80
> > +#define SY7802_REG_LAST_FLASH		0x81
> > +#define SY7802_REG_VLED_MONITOR		0x30
> > +#define SY7802_REG_ADC_DELAY		0x31
> > +#define SY7802_REG_DEV_ID		0xff
> > +
> > +#define SY7802_MODE_OFF		0
> > +#define SY7802_MODE_TORCH	2
> > +#define SY7802_MODE_FLASH	3
> > +#define SY7802_MODE_MASK	GENMASK(1, 0)
> > +
> > +#define SY7802_LEDS_SHIFT	3
> > +#define SY7802_LEDS_MASK(_id)	(BIT(_id) << SY7802_LEDS_SHIFT)
> > +#define SY7802_LEDS_MASK_ALL	(SY7802_LEDS_MASK(0) |
> > SY7802_LEDS_MASK(1))
> > +
> > +#define SY7802_TORCH_CURRENT_SHIFT	3
> > +#define SY7802_TORCH_CURRENT_MASK(_id) \
> > +	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
> > +#define SY7802_TORCH_CURRENT_MASK_ALL \
> > +	(SY7802_TORCH_CURRENT_MASK(0) |
> > SY7802_TORCH_CURRENT_MASK(1))
> > +
> > +#define SY7802_FLASH_CURRENT_SHIFT	4
> > +#define SY7802_FLASH_CURRENT_MASK(_id) \
> > +	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
> > +#define SY7802_FLASH_CURRENT_MASK_ALL \
> > +	(SY7802_FLASH_CURRENT_MASK(0) |
> > SY7802_FLASH_CURRENT_MASK(1))
> > +
> > +#define SY7802_TIMEOUT_DEFAULT_US	512000U
> > +#define SY7802_TIMEOUT_MIN_US		32000U
> > +#define SY7802_TIMEOUT_MAX_US		1024000U
> > +#define SY7802_TIMEOUT_STEPSIZE_US	32000U
> > +
> > +#define SY7802_TORCH_BRIGHTNESS_MAX 8
> > +
> > +#define SY7802_FLASH_BRIGHTNESS_DEFAULT	14
> > +#define SY7802_FLASH_BRIGHTNESS_MIN	0
> > +#define SY7802_FLASH_BRIGHTNESS_MAX	15
> > +#define SY7802_FLASH_BRIGHTNESS_STEP	1
> > +
> > +#define SY7802_FLAG_TIMEOUT			BIT(0)
> > +#define SY7802_FLAG_THERMAL_SHUTDOWN		BIT(1)
> > +#define SY7802_FLAG_LED_FAULT			BIT(2)
> > +#define SY7802_FLAG_TX1_INTERRUPT		BIT(3)
> > +#define SY7802_FLAG_TX2_INTERRUPT		BIT(4)
> > +#define SY7802_FLAG_LED_THERMAL_FAULT		BIT(5)
> > +#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW	BIT(6)
> > +#define SY7802_FLAG_INPUT_VOLTAGE_LOW		BIT(7)
> > +
> > +#define SY7802_CHIP_ID	0x51
> > +
> > +static const struct reg_default sy7802_regmap_defs[] = {
> > +	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
> > +	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
> > +	{ SY7802_REG_FLASH_BRIGHTNESS,
> > SY7802_FLASH_BRIGHTNESS_DEFAULT |
> > +		SY7802_FLASH_BRIGHTNESS_DEFAULT <<
> > SY7802_FLASH_CURRENT_SHIFT },
> > +	{ SY7802_REG_FLASH_DURATION, 0x6f },
> > +	{ SY7802_REG_FLAGS, 0x0 },
> > +	{ SY7802_REG_CONFIG_1, 0x68 },
> > +	{ SY7802_REG_CONFIG_2, 0xf0 },
> 
> Not your fault, but this interface is frustrating since we have no
> idea
> what these register values mean.  IMHO, they should be defined and
> ORed
> together in some human readable way.
> 
> I say that it's not your fault because I see that this is the most
> common usage.
> 

I don't know how to interpret some bits of the default values. I don't
have the documentation and changing the bits and observing the behavior
of the device also didn't help.

Should I remove the entries from sy7802_regmap_defs, which have values
that we don't fully understand?

Regards,
André

Re: [PATCH v4 2/3] leds: sy7802: Add support for Silergy SY7802 flash LED controller

[Lee Jones]

On Sat, 22 Jun 2024, André Apitzsch wrote:

> Hello Lee,
> 
> Am Freitag, dem 21.06.2024 um 11:26 +0100 schrieb Lee Jones:
> > On Sun, 16 Jun 2024, André Apitzsch via B4 Relay wrote:
> > 
> > > From: André Apitzsch <git@apitzsch.eu>
> > > 
> > > The SY7802 is a current-regulated charge pump which can regulate
> > > two
> > > current levels for Flash and Torch modes.
> > > 
> > > It is a high-current synchronous boost converter with 2-channel
> > > high
> > > side current sources. Each channel is able to deliver 900mA
> > > current.
> > > 
> > > Signed-off-by: André Apitzsch <git@apitzsch.eu>
> > > ---
> > >  drivers/leds/flash/Kconfig       |  11 +
> > >  drivers/leds/flash/Makefile      |   1 +
> > >  drivers/leds/flash/leds-sy7802.c | 542
> > > +++++++++++++++++++++++++++++++++++++++
> > >  3 files changed, 554 insertions(+)
> > 
> > Generally very nice.
> > 
> > Just a couple of teensy nits to fix then add my and resubmit please.
> > 
> > Acked-by: Lee Jones <lee@kernel.org>
> > 
> > > [...]
> > > diff --git a/drivers/leds/flash/leds-sy7802.c
> > > b/drivers/leds/flash/leds-sy7802.c
> > > new file mode 100644
> > > index 000000000000..c4bea55a62d0
> > > --- /dev/null
> > > +++ b/drivers/leds/flash/leds-sy7802.c
> > > @@ -0,0 +1,542 @@
> > > +// SPDX-License-Identifier: GPL-2.0-or-later
> > > +/*
> > > + * Silergy SY7802 flash LED driver with I2C interface
> > 
> > "an I2C interface"
> > 
> > Or
> > 
> > "I2C interfaces"
> > 
> > > + * Copyright 2024 André Apitzsch <git@apitzsch.eu>
> > > + */
> > > +
> > > +#include <linux/gpio/consumer.h>
> > > +#include <linux/i2c.h>
> > > +#include <linux/kernel.h>
> > > +#include <linux/led-class-flash.h>
> > > +#include <linux/module.h>
> > > +#include <linux/mutex.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/regulator/consumer.h>
> > > +
> > > +#define SY7802_MAX_LEDS 2
> > > +#define SY7802_LED_JOINT 2
> > > +
> > > +#define SY7802_REG_ENABLE		0x10
> > > +#define SY7802_REG_TORCH_BRIGHTNESS	0xa0
> > > +#define SY7802_REG_FLASH_BRIGHTNESS	0xb0
> > > +#define SY7802_REG_FLASH_DURATION	0xc0
> > > +#define SY7802_REG_FLAGS		0xd0
> > > +#define SY7802_REG_CONFIG_1		0xe0
> > > +#define SY7802_REG_CONFIG_2		0xf0
> > > +#define SY7802_REG_VIN_MONITOR		0x80
> > > +#define SY7802_REG_LAST_FLASH		0x81
> > > +#define SY7802_REG_VLED_MONITOR		0x30
> > > +#define SY7802_REG_ADC_DELAY		0x31
> > > +#define SY7802_REG_DEV_ID		0xff
> > > +
> > > +#define SY7802_MODE_OFF		0
> > > +#define SY7802_MODE_TORCH	2
> > > +#define SY7802_MODE_FLASH	3
> > > +#define SY7802_MODE_MASK	GENMASK(1, 0)
> > > +
> > > +#define SY7802_LEDS_SHIFT	3
> > > +#define SY7802_LEDS_MASK(_id)	(BIT(_id) << SY7802_LEDS_SHIFT)
> > > +#define SY7802_LEDS_MASK_ALL	(SY7802_LEDS_MASK(0) |
> > > SY7802_LEDS_MASK(1))
> > > +
> > > +#define SY7802_TORCH_CURRENT_SHIFT	3
> > > +#define SY7802_TORCH_CURRENT_MASK(_id) \
> > > +	(GENMASK(2, 0) << (SY7802_TORCH_CURRENT_SHIFT * (_id)))
> > > +#define SY7802_TORCH_CURRENT_MASK_ALL \
> > > +	(SY7802_TORCH_CURRENT_MASK(0) |
> > > SY7802_TORCH_CURRENT_MASK(1))
> > > +
> > > +#define SY7802_FLASH_CURRENT_SHIFT	4
> > > +#define SY7802_FLASH_CURRENT_MASK(_id) \
> > > +	(GENMASK(3, 0) << (SY7802_FLASH_CURRENT_SHIFT * (_id)))
> > > +#define SY7802_FLASH_CURRENT_MASK_ALL \
> > > +	(SY7802_FLASH_CURRENT_MASK(0) |
> > > SY7802_FLASH_CURRENT_MASK(1))
> > > +
> > > +#define SY7802_TIMEOUT_DEFAULT_US	512000U
> > > +#define SY7802_TIMEOUT_MIN_US		32000U
> > > +#define SY7802_TIMEOUT_MAX_US		1024000U
> > > +#define SY7802_TIMEOUT_STEPSIZE_US	32000U
> > > +
> > > +#define SY7802_TORCH_BRIGHTNESS_MAX 8
> > > +
> > > +#define SY7802_FLASH_BRIGHTNESS_DEFAULT	14
> > > +#define SY7802_FLASH_BRIGHTNESS_MIN	0
> > > +#define SY7802_FLASH_BRIGHTNESS_MAX	15
> > > +#define SY7802_FLASH_BRIGHTNESS_STEP	1
> > > +
> > > +#define SY7802_FLAG_TIMEOUT			BIT(0)
> > > +#define SY7802_FLAG_THERMAL_SHUTDOWN		BIT(1)
> > > +#define SY7802_FLAG_LED_FAULT			BIT(2)
> > > +#define SY7802_FLAG_TX1_INTERRUPT		BIT(3)
> > > +#define SY7802_FLAG_TX2_INTERRUPT		BIT(4)
> > > +#define SY7802_FLAG_LED_THERMAL_FAULT		BIT(5)
> > > +#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW	BIT(6)
> > > +#define SY7802_FLAG_INPUT_VOLTAGE_LOW		BIT(7)
> > > +
> > > +#define SY7802_CHIP_ID	0x51
> > > +
> > > +static const struct reg_default sy7802_regmap_defs[] = {
> > > +	{ SY7802_REG_ENABLE, SY7802_LEDS_MASK_ALL },
> > > +	{ SY7802_REG_TORCH_BRIGHTNESS, 0x92 },
> > > +	{ SY7802_REG_FLASH_BRIGHTNESS,
> > > SY7802_FLASH_BRIGHTNESS_DEFAULT |
> > > +		SY7802_FLASH_BRIGHTNESS_DEFAULT <<
> > > SY7802_FLASH_CURRENT_SHIFT },
> > > +	{ SY7802_REG_FLASH_DURATION, 0x6f },
> > > +	{ SY7802_REG_FLAGS, 0x0 },
> > > +	{ SY7802_REG_CONFIG_1, 0x68 },
> > > +	{ SY7802_REG_CONFIG_2, 0xf0 },
> > 
> > Not your fault, but this interface is frustrating since we have no
> > idea
> > what these register values mean.  IMHO, they should be defined and
> > ORed
> > together in some human readable way.
> > 
> > I say that it's not your fault because I see that this is the most
> > common usage.
> > 
> 
> I don't know how to interpret some bits of the default values. I don't
> have the documentation and changing the bits and observing the behavior
> of the device also didn't help.

And this is the problem.

> Should I remove the entries from sy7802_regmap_defs, which have values
> that we don't fully understand?

No, as I say, it's not your fault.  Sadly this appears to be the norm.

-- 
Lee Jones [李琼斯]

[PATCH v4 3/3] arm64: dts: qcom: msm8939-longcheer-l9100: Add rear flash

[André Apitzsch via B4 Relay]

From: André Apitzsch <git@apitzsch.eu>

The phone has a Silergy SY7802 flash LED controller.

Signed-off-by: André Apitzsch <git@apitzsch.eu>
---
 .../boot/dts/qcom/msm8939-longcheer-l9100.dts      | 26 ++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/msm8939-longcheer-l9100.dts b/arch/arm64/boot/dts/qcom/msm8939-longcheer-l9100.dts
index e3404c4455cf..528737929274 100644
--- a/arch/arm64/boot/dts/qcom/msm8939-longcheer-l9100.dts
+++ b/arch/arm64/boot/dts/qcom/msm8939-longcheer-l9100.dts
@@ -159,6 +159,25 @@ led@2 {
 			};
 		};
 	};
+
+	flash-led-controller@53 {
+		compatible = "silergy,sy7802";
+		reg = <0x53>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		enable-gpios = <&tlmm 16 GPIO_ACTIVE_HIGH>;
+
+		pinctrl-0 = <&camera_rear_flash_default>;
+		pinctrl-names = "default";
+
+		led@0 {
+			reg = <0>;
+			function = LED_FUNCTION_FLASH;
+			color = <LED_COLOR_ID_WHITE>;
+			led-sources = <0>, <1>;
+		};
+	};
 };
 
 &blsp_i2c3 {
@@ -318,6 +337,13 @@ camera_front_flash_default: camera-front-flash-default-state {
 		bias-disable;
 	};
 
+	camera_rear_flash_default: camera-rear-flash-default-state {
+		pins = "gpio9", "gpio16", "gpio51";
+		function = "gpio";
+		drive-strength = <2>;
+		bias-disable;
+	};
+
 	gpio_hall_sensor_default: gpio-hall-sensor-default-state {
 		pins = "gpio20";
 		function = "gpio";

-- 
2.45.2