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

From: André Apitzsch via B4 Relay
Date: Wed Mar 27 2024 - 18:57:51 EST


From: André Apitzsch <git@xxxxxxxxxxx>

Add support for SY7802 flash LED controller. It can support up to 1.8A
flash current.

Signed-off-by: André Apitzsch <git@xxxxxxxxxxx>
---
drivers/leds/flash/Kconfig | 11 +
drivers/leds/flash/Makefile | 1 +
drivers/leds/flash/leds-sy7802.c | 532 +++++++++++++++++++++++++++++++++++++++
3 files changed, 544 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..c03a571b0e08
--- /dev/null
+++ b/drivers/leds/flash/leds-sy7802.c
@@ -0,0 +1,532 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Silergy SY7802 flash LED driver with I2C interface
+ *
+ * Copyright 2024 André Apitzsch <git@xxxxxxxxxxx>
+ */
+
+#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 (1 << 0)
+#define SY7802_FLAG_THERMAL_SHUTDOWN (1 << 1)
+#define SY7802_FLAG_LED_FAULT (1 << 2)
+#define SY7802_FLAG_TX1_INTERRUPT (1 << 3)
+#define SY7802_FLAG_TX2_INTERRUPT (1 << 4)
+#define SY7802_FLAG_LED_THERMAL_FAULT (1 << 5)
+#define SY7802_FLAG_FLASH_INPUT_VOLTAGE_LOW (1 << 6)
+#define SY7802_FLAG_INPUT_VOLTAGE_LOW (1 << 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_no;
+};
+
+struct sy7802 {
+ struct mutex mutex;
+ struct device *dev;
+ struct regmap *regmap;
+
+ 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 level)
+{
+ struct sy7802_led *led = container_of(lcdev, struct sy7802_led, flash.led_cdev);
+ u32 led_enable_mask = led->led_no == SY7802_LED_JOINT ? SY7802_LEDS_MASK_ALL :
+ SY7802_LEDS_MASK(led->led_no);
+ u32 enable_mask = SY7802_MODE_MASK | led_enable_mask;
+ u32 val = level ? led_enable_mask : SY7802_MODE_OFF;
+ struct sy7802 *chip = led->chip;
+ u32 curr;
+ u32 mask;
+ int ret;
+
+ mutex_lock(&chip->mutex);
+
+ /*
+ * There is only one set of flash control logic, and this flag is used to check if 'strobe'
+ * is currently being used.
+ */
+ if (chip->fled_strobe_used) {
+ dev_warn(chip->dev, "Please disable strobe first [%d]\n", chip->fled_strobe_used);
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ if (level)
+ curr = chip->fled_torch_used | BIT(led->led_no);
+ else
+ curr = chip->fled_torch_used & ~BIT(led->led_no);
+
+ if (curr)
+ val |= SY7802_MODE_TORCH;
+
+ /* Torch needs to be disabled first to apply new brightness */
+ ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_MASK,
+ SY7802_MODE_OFF);
+ if (ret)
+ goto unlock;
+
+ mask = led->led_no == SY7802_LED_JOINT ? SY7802_TORCH_CURRENT_MASK_ALL :
+ SY7802_TORCH_CURRENT_MASK(led->led_no);
+
+ /* Register expects brightness between 0 and MAX_BRIGHTNESS - 1 */
+ if (level)
+ level -= 1;
+
+ level |= (level << SY7802_TORCH_CURRENT_SHIFT);
+
+ ret = regmap_update_bits(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, mask, level);
+ if (ret)
+ goto unlock;
+
+ ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
+ if (ret)
+ goto unlock;
+
+ chip->fled_torch_used = curr;
+
+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 mask;
+ int ret;
+
+ val |= (val << SY7802_FLASH_CURRENT_SHIFT);
+ mask = led->led_no == SY7802_LED_JOINT ? SY7802_FLASH_CURRENT_MASK_ALL :
+ SY7802_FLASH_CURRENT_MASK(led->led_no);
+
+ mutex_lock(&chip->mutex);
+ ret = regmap_update_bits(chip->regmap, SY7802_REG_FLASH_BRIGHTNESS, 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);
+ u32 led_enable_mask = led->led_no == SY7802_LED_JOINT ? SY7802_LEDS_MASK_ALL :
+ SY7802_LEDS_MASK(led->led_no);
+ u32 enable_mask = SY7802_MODE_MASK | led_enable_mask;
+ u32 val = state ? led_enable_mask : SY7802_MODE_OFF;
+ struct sy7802 *chip = led->chip;
+ u32 curr;
+ int ret;
+
+ mutex_lock(&chip->mutex);
+
+ /*
+ * There is only one set of flash control logic, and this flag is used to check if 'torch'
+ * is currently being used.
+ */
+ if (chip->fled_torch_used) {
+ dev_warn(chip->dev, "Please disable torch first [0x%x]\n", chip->fled_torch_used);
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ if (state)
+ curr = chip->fled_strobe_used | BIT(led->led_no);
+ else
+ curr = chip->fled_strobe_used & ~BIT(led->led_no);
+
+ if (curr)
+ val |= SY7802_MODE_FLASH;
+
+ ret = regmap_update_bits(chip->regmap, SY7802_REG_ENABLE, enable_mask, val);
+
+ if (ret)
+ goto unlock;
+
+ chip->fled_strobe_used = curr;
+
+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_no));
+ 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_no);
+ return ret;
+ }
+
+ return ret;
+}
+
+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_no = 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, "Chip reported wrong ID: %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), *child;
+ int i = 0;
+ int ret;
+
+ regmap_write(chip->regmap, SY7802_REG_ENABLE, SY7802_MODE_OFF);
+ regmap_write(chip->regmap, SY7802_REG_TORCH_BRIGHTNESS, LED_OFF);
+
+ for_each_available_child_of_node(np, child) {
+ struct sy7802_led *led = chip->leds + i;
+
+ led->chip = chip;
+ led->led_no = i;
+
+ ret = sy7802_init_flash_properties(chip->dev, led, child);
+ if (ret) {
+ of_node_put(child);
+ return ret;
+ }
+
+ ret = sy7802_led_register(chip->dev, led, child);
+ if (ret) {
+ of_node_put(child);
+ return ret;
+ }
+
+ i++;
+ }
+ return 0;
+}
+
+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,
+ "No child node or node count over max led number %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");
+
+ chip->regmap = devm_regmap_init_i2c(client, &sy7802_regmap_config);
+ if (IS_ERR(chip->regmap)) {
+ regulator_disable(chip->vin_regulator);
+ return dev_err_probe(dev, PTR_ERR(chip->regmap),
+ "Failed to allocate register map.\n");
+ }
+
+ ret = sy7802_probe_dt(chip);
+ if (ret < 0) {
+ regulator_disable(chip->vin_regulator);
+ return ret;
+ }
+
+ sy7802_enable(chip);
+
+ ret = sy7802_chip_check(chip);
+ if (ret) {
+ sy7802_disable(chip);
+ regulator_disable(chip->vin_regulator);
+ return ret;
+ }
+
+ mutex_init(&chip->mutex);
+
+ return ret;
+}
+
+static void sy7802_remove(struct i2c_client *client)
+{
+ struct sy7802 *chip = i2c_get_clientdata(client);
+
+ sy7802_disable(chip);
+
+ mutex_destroy(&chip->mutex);
+ regulator_disable(chip->vin_regulator);
+}
+
+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,
+ .remove = sy7802_remove,
+};
+
+module_i2c_driver(sy7802_driver);
+
+MODULE_AUTHOR("André Apitzsch <git@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Silergy SY7802 flash LED driver");
+MODULE_LICENSE("GPL");

--
2.44.0