Re: [PATCH v16 2/2] leds: flash: mt6370: Add MediaTek MT6370 flashlight support

Lee Jones
2023-01-27T10:20:42Z

Jacek, Andy,

On Tue, 17 Jan 2023, ChiaEn Wu wrote:

> From: ChiYuan Huang <cy_huang@richtek.com>
>
> The MediaTek MT6370 is a highly-integrated smart power management IC,
> which includes a single cell Li-Ion/Li-Polymer switching battery
> charger, a USB Type-C & Power Delivery (PD) controller, dual Flash
> LED current sources, a RGB LED driver, a backlight WLED driver,
> a display bias driver and a general LDO for portable devices.
>
> Add support for the MT6370 Flash LED driver. Flash LED in MT6370
> has 2 channels and support torch/strobe mode.
>
> Co-developed-by: Alice Chen <alice_chen@richtek.com>
> Signed-off-by: Alice Chen <alice_chen@richtek.com>
> Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
> Signed-off-by: ChiaEn Wu <chiaen_wu@richtek.com>
> ---
>
> v16
> - Remove blank line in the head text.
> - For enum, declared the first element as 0
> - Remove unusd default state and state define.
> - For mt6370_priv, 'dev' member only be used once. Remove it.
> - Refine assign operator for '?:', no need to use brackets for the
> judgement.
> - Refine '_mt6370_flash_brightness_set' function for else case.
> - Modify 'struct led_flash_setting *setting' to 'struct
> led_flash_setting *s'. This can reduce line count.
> - Remove the revert logic in 'mt6370_strobe_set' function.
> No need to do it.
> - Remove mutex usage in timeout_set and fault_get.
> Regmap lock already protect it.
> - Add default label for switch case in fault_get.
> - Directly assign fwnode as the parameter for 'mt6370_led_register' and
> 'mt6370_init_flash_config'.
> - Due to struct mt6370_priv 'dev' member removed, pass 'dev' as the
> input parameter for 'mt6370_init_flash_config'.
> - For some if judgement, remove 'num > MT6370_MAX_LEDS'.
> There's no need to check it. The below code already protect it.
> - Group mt6360 and mt6370 in Makefile.
> - SPDX already declared as 'GPL v2-only', change MODULE_LICENSE to
> 'GPL'.
> - Add one more author for ChiYuan Huang.
> ---
> drivers/leds/flash/Kconfig | 13 +
> drivers/leds/flash/Makefile | 1 +
> drivers/leds/flash/leds-mt6370-flash.c | 596 +++++++++++++++++++++++++++++++++
> 3 files changed, 610 insertions(+)
> create mode 100644 drivers/leds/flash/leds-mt6370-flash.c

I see that you guys have been super helpful reviewing this in the past.

Have your queries now been addressed?

> diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
> index d3eb689..49d8922 100644
> --- a/drivers/leds/flash/Kconfig
> +++ b/drivers/leds/flash/Kconfig
> @@ -61,6 +61,19 @@ config LEDS_MT6360
> Independent current sources supply for each flash LED support torch
> and strobe mode.
>
> +config LEDS_MT6370_FLASH
> + tristate "Flash LED Support for MediaTek MT6370 PMIC"
> + depends on LEDS_CLASS
> + depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
> + depends on MFD_MT6370
> + help
> + Support 2 channels and torch/strobe mode.
> + Say Y here to enable support for
> + MT6370_FLASH_LED device.
> +
> + This driver can also be built as a module. If so, the module
> + will be called "leds-mt6370-flash".
> +
> config LEDS_RT4505
> tristate "LED support for RT4505 flashlight controller"
> depends on I2C && OF
> diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
> index 0acbddc..4665e8e 100644
> --- a/drivers/leds/flash/Makefile
> +++ b/drivers/leds/flash/Makefile
> @@ -1,6 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0
>
> obj-$(CONFIG_LEDS_MT6360) += leds-mt6360.o
> +obj-$(CONFIG_LEDS_MT6370_FLASH) += leds-mt6370-flash.o
> obj-$(CONFIG_LEDS_AAT1290) += leds-aat1290.o
> obj-$(CONFIG_LEDS_AS3645A) += leds-as3645a.o
> obj-$(CONFIG_LEDS_KTD2692) += leds-ktd2692.o
> diff --git a/drivers/leds/flash/leds-mt6370-flash.c b/drivers/leds/flash/leds-mt6370-flash.c
> new file mode 100644
> index 00000000..e5c4c94
> --- /dev/null
> +++ b/drivers/leds/flash/leds-mt6370-flash.c
> @@ -0,0 +1,596 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2022 Richtek Technology Corp.
> + *
> + * Authors:
> + * Alice Chen <alice_chen@richtek.com>
> + * ChiYuan Huang <cy_huang@richtek.com>
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/led-class-flash.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +
> +#include <media/v4l2-flash-led-class.h>
> +
> +enum {
> + MT6370_LED_FLASH1 = 0,
> + MT6370_LED_FLASH2,
> + MT6370_MAX_LEDS
> +};
> +
> +/* Virtual definition for multicolor */
> +
> +#define MT6370_REG_FLEDEN 0x17E
> +#define MT6370_REG_STRBTO 0x173
> +#define MT6370_REG_CHGSTAT2 0x1D1
> +#define MT6370_REG_FLEDSTAT1 0x1D9
> +#define MT6370_REG_FLEDISTRB(_id) (0x174 + 4 * (_id))
> +#define MT6370_REG_FLEDITOR(_id) (0x175 + 4 * (_id))
> +#define MT6370_ITORCH_MASK GENMASK(4, 0)
> +#define MT6370_ISTROBE_MASK GENMASK(6, 0)
> +#define MT6370_STRBTO_MASK GENMASK(6, 0)
> +#define MT6370_TORCHEN_MASK BIT(3)
> +#define MT6370_STROBEN_MASK BIT(2)
> +#define MT6370_FLCSEN_MASK(_id) BIT(MT6370_LED_FLASH2 - (_id))
> +#define MT6370_FLCSEN_MASK_ALL GENMASK(1, 0)
> +#define MT6370_FLEDCHGVINOVP_MASK BIT(3)
> +#define MT6370_FLED1STRBTO_MASK BIT(11)
> +#define MT6370_FLED2STRBTO_MASK BIT(10)
> +#define MT6370_FLED1STRB_MASK BIT(9)
> +#define MT6370_FLED2STRB_MASK BIT(8)
> +#define MT6370_FLED1SHORT_MASK BIT(7)
> +#define MT6370_FLED2SHORT_MASK BIT(6)
> +#define MT6370_FLEDLVF_MASK BIT(3)
> +
> +#define MT6370_LED_JOINT 2
> +#define MT6370_RANGE_FLED_REG 4
> +#define MT6370_ITORCH_MIN_uA 25000
> +#define MT6370_ITORCH_STEP_uA 12500
> +#define MT6370_ITORCH_MAX_uA 400000
> +#define MT6370_ITORCH_DOUBLE_MAX_uA 800000
> +#define MT6370_ISTRB_MIN_uA 50000
> +#define MT6370_ISTRB_STEP_uA 12500
> +#define MT6370_ISTRB_MAX_uA 1500000
> +#define MT6370_ISTRB_DOUBLE_MAX_uA 3000000
> +#define MT6370_STRBTO_MIN_US 64000
> +#define MT6370_STRBTO_STEP_US 32000
> +#define MT6370_STRBTO_MAX_US 2432000
> +
> +#define to_mt6370_led(ptr, member) container_of(ptr, struct mt6370_led, member)
> +
> +struct mt6370_led {
> + struct led_classdev_flash flash;
> + struct v4l2_flash *v4l2_flash;
> + struct mt6370_priv *priv;
> + u8 led_no;
> +};
> +
> +struct mt6370_priv {
> + struct regmap *regmap;
> + struct mutex lock;
> + unsigned int fled_strobe_used;
> + unsigned int fled_torch_used;
> + unsigned int leds_active;
> + unsigned int leds_count;
> + struct mt6370_led leds[];
> +};
> +
> +static int mt6370_torch_brightness_set(struct led_classdev *lcdev,
> + enum led_brightness level)
> +{
> + struct mt6370_led *led = to_mt6370_led(lcdev, flash.led_cdev);
> + struct mt6370_priv *priv = led->priv;
> + u32 led_enable_mask = led->led_no == MT6370_LED_JOINT ?
> + MT6370_FLCSEN_MASK_ALL :
> + MT6370_FLCSEN_MASK(led->led_no);
> + u32 enable_mask = MT6370_TORCHEN_MASK | led_enable_mask;
> + u32 val = level ? led_enable_mask : 0;
> + u32 curr;
> + int ret, i;
> +
> + mutex_lock(&priv->lock);
> +
> + /*
> + * There is only one set of flash control logic, and this
> + * flag is used to check if 'strobe' is currently being used.
> + */
> + if (priv->fled_strobe_used) {
> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n",
> + priv->fled_strobe_used);
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + if (level)
> + curr = priv->fled_torch_used | BIT(led->led_no);
> + else
> + curr = priv->fled_torch_used & ~BIT(led->led_no);
> +
> + if (curr)
> + val |= MT6370_TORCHEN_MASK;
> +
> + if (level) {
> + level -= 1;
> + if (led->led_no == MT6370_LED_JOINT) {
> + u32 flevel[MT6370_MAX_LEDS];
> +
> + flevel[0] = level / 2;
> + flevel[1] = level - flevel[0];
> + for (i = 0; i < MT6370_MAX_LEDS; i++) {
> + ret = regmap_update_bits(priv->regmap,
> + MT6370_REG_FLEDITOR(i),
> + MT6370_ITORCH_MASK, flevel[i]);
> + if (ret)
> + goto unlock;
> + }
> + } else {
> + ret = regmap_update_bits(priv->regmap,
> + MT6370_REG_FLEDITOR(led->led_no),
> + MT6370_ITORCH_MASK, level);
> + if (ret)
> + goto unlock;
> + }
> + }
> +
> + ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN,
> + enable_mask, val);
> + if (ret)
> + goto unlock;
> +
> + priv->fled_torch_used = curr;
> +
> +unlock:
> + mutex_unlock(&priv->lock);
> + return ret;
> +}
> +
> +static int mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev,
> + u32 brightness)
> +{
> + /*
> + * Because of the current spikes when turning on the flash,
> + * the brightness should be kept by the LED framework. This
> + * empty function is used to prevent checking failure when
> + * led_classdev_flash registers ops.
> + */
> + return 0;
> +}
> +
> +static int _mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev,
> + u32 brightness)
> +{
> + struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
> + struct mt6370_priv *priv = led->priv;
> + struct led_flash_setting *setting = &fl_cdev->brightness;
> + u32 val = (brightness - setting->min) / setting->step;
> + int ret, i;
> +
> + if (led->led_no == MT6370_LED_JOINT) {
> + u32 flevel[MT6370_MAX_LEDS];
> +
> + flevel[0] = val / 2;
> + flevel[1] = val - flevel[0];
> + for (i = 0; i < MT6370_MAX_LEDS; i++) {
> + ret = regmap_update_bits(priv->regmap,
> + MT6370_REG_FLEDISTRB(i),
> + MT6370_ISTROBE_MASK, flevel[i]);
> + if (ret)
> + break;
> + }
> + } else
> + ret = regmap_update_bits(priv->regmap,
> + MT6370_REG_FLEDISTRB(led->led_no),
> + MT6370_ISTROBE_MASK, val);
> +
> + return ret;
> +}
> +
> +static int mt6370_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
> +{
> + struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
> + struct mt6370_priv *priv = led->priv;
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> + struct led_flash_setting *s = &fl_cdev->brightness;
> + u32 led_enable_mask = led->led_no == MT6370_LED_JOINT ?
> + MT6370_FLCSEN_MASK_ALL :
> + MT6370_FLCSEN_MASK(led->led_no);
> + u32 enable_mask = MT6370_STROBEN_MASK | led_enable_mask;
> + u32 val = state ? led_enable_mask : 0;
> + u32 curr;
> + int ret;
> +
> + mutex_lock(&priv->lock);
> +
> + /*
> + * There is only one set of flash control logic, and this
> + * flag is used to check if 'torch' is currently being used.
> + */
> + if (priv->fled_torch_used) {
> + dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n",
> + priv->fled_torch_used);
> + ret = -EBUSY;
> + goto unlock;
> + }
> +
> + if (state)
> + curr = priv->fled_strobe_used | BIT(led->led_no);
> + else
> + curr = priv->fled_strobe_used & ~BIT(led->led_no);
> +
> + if (curr)
> + val |= MT6370_STROBEN_MASK;
> +
> + ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, enable_mask,
> + val);
> + if (ret) {
> + dev_err(lcdev->dev, "[%d] control current source %d fail\n",
> + led->led_no, state);
> + goto unlock;
> + }
> +
> + /*
> + * If the flash needs to turn on, configure the flash current to
> + * ramp up to the setting value. Otherwise, always revert to the
> + * minimum one.
> + */
> + ret = _mt6370_flash_brightness_set(fl_cdev, state ? s->val : s->min);
> + if (ret) {
> + dev_err(lcdev->dev, "[%d] Failed to set brightness\n", led->led_no);
> + goto unlock;
> + }
> +
> + /*
> + * For the flash to turn on/off, we must wait for HW ramping
> + * up/down time 5ms/500us to prevent the unexpected problem.
> + */
> + if (!priv->fled_strobe_used && curr)
> + usleep_range(5000, 6000);
> + else if (priv->fled_strobe_used && !curr)
> + usleep_range(500, 600);
> +
> + priv->fled_strobe_used = curr;
> +
> +unlock:
> + mutex_unlock(&priv->lock);
> + return ret;
> +}
> +
> +static int mt6370_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> +{
> + struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
> + struct mt6370_priv *priv = led->priv;
> +
> + mutex_lock(&priv->lock);
> + *state = !!(priv->fled_strobe_used & BIT(led->led_no));
> + mutex_unlock(&priv->lock);
> +
> + return 0;
> +}
> +
> +static int mt6370_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
> +{
> + struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
> + struct mt6370_priv *priv = led->priv;
> + struct led_flash_setting *s = &fl_cdev->timeout;
> + u32 val = (timeout - s->min) / s->step;
> +
> + return regmap_update_bits(priv->regmap, MT6370_REG_STRBTO,
> + MT6370_STRBTO_MASK, val);
> +}
> +
> +static int mt6370_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
> +{
> + struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
> + struct mt6370_priv *priv = led->priv;
> + u16 fled_stat;
> + unsigned int chg_stat, strobe_timeout_mask, fled_short_mask;
> + u32 rfault = 0;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, MT6370_REG_CHGSTAT2, &chg_stat);
> + if (ret)
> + return ret;
> +
> + ret = regmap_raw_read(priv->regmap, MT6370_REG_FLEDSTAT1, &fled_stat,
> + sizeof(fled_stat));
> + if (ret)
> + return ret;
> +
> + switch (led->led_no) {
> + case MT6370_LED_FLASH1:
> + strobe_timeout_mask = MT6370_FLED1STRBTO_MASK;
> + fled_short_mask = MT6370_FLED1SHORT_MASK;
> + break;
> +
> + case MT6370_LED_FLASH2:
> + strobe_timeout_mask = MT6370_FLED2STRBTO_MASK;
> + fled_short_mask = MT6370_FLED2SHORT_MASK;
> + break;
> +
> + case MT6370_LED_JOINT:
> + strobe_timeout_mask = MT6370_FLED1STRBTO_MASK |
> + MT6370_FLED2STRBTO_MASK;
> + fled_short_mask = MT6370_FLED1SHORT_MASK |
> + MT6370_FLED2SHORT_MASK;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + if (chg_stat & MT6370_FLEDCHGVINOVP_MASK)
> + rfault |= LED_FAULT_INPUT_VOLTAGE;
> +
> + if (fled_stat & strobe_timeout_mask)
> + rfault |= LED_FAULT_TIMEOUT;
> +
> + if (fled_stat & fled_short_mask)
> + rfault |= LED_FAULT_SHORT_CIRCUIT;
> +
> + if (fled_stat & MT6370_FLEDLVF_MASK)
> + rfault |= LED_FAULT_UNDER_VOLTAGE;
> +
> + *fault = rfault;
> + return ret;
> +}
> +
> +static const struct led_flash_ops mt6370_flash_ops = {
> + .flash_brightness_set = mt6370_flash_brightness_set,
> + .strobe_set = mt6370_strobe_set,
> + .strobe_get = mt6370_strobe_get,
> + .timeout_set = mt6370_timeout_set,
> + .fault_get = mt6370_fault_get,
> +};
> +
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +static int mt6370_flash_external_strobe_set(struct v4l2_flash *v4l2_flash,
> + bool enable)
> +{
> + struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
> + struct mt6370_led *led = to_mt6370_led(flash, flash);
> + struct mt6370_priv *priv = led->priv;
> + u32 mask = led->led_no == MT6370_LED_JOINT ? MT6370_FLCSEN_MASK_ALL :
> + MT6370_FLCSEN_MASK(led->led_no);
> + u32 val = enable ? mask : 0;
> + int ret;
> +
> + mutex_lock(&priv->lock);
> +
> + ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, mask, val);
> + if (ret)
> + goto unlock;
> +
> + if (enable)
> + priv->fled_strobe_used |= BIT(led->led_no);
> + else
> + priv->fled_strobe_used &= ~BIT(led->led_no);
> +
> +unlock:
> + mutex_unlock(&priv->lock);
> + return ret;
> +}
> +
> +static const struct v4l2_flash_ops v4l2_flash_ops = {
> + .external_strobe_set = mt6370_flash_external_strobe_set,
> +};
> +
> +static void mt6370_init_v4l2_flash_config(struct mt6370_led *led,
> + struct v4l2_flash_config *cfg)
> +{
> + struct led_classdev *lcdev;
> + struct led_flash_setting *s = &cfg->intensity;
> +
> + lcdev = &led->flash.led_cdev;
> +
> + s->min = MT6370_ITORCH_MIN_uA;
> + s->step = MT6370_ITORCH_STEP_uA;
> + s->val = s->max = s->min + (lcdev->max_brightness - 1) * s->step;
> +
> + cfg->has_external_strobe = 1;
> + strscpy(cfg->dev_name, dev_name(lcdev->dev), sizeof(cfg->dev_name));
> +
> + cfg->flash_faults = LED_FAULT_SHORT_CIRCUIT | LED_FAULT_TIMEOUT |
> + LED_FAULT_INPUT_VOLTAGE | LED_FAULT_UNDER_VOLTAGE;
> +}
> +#else
> +static const struct v4l2_flash_ops v4l2_flash_ops;
> +static void mt6370_init_v4l2_flash_config(struct mt6370_led *led,
> + struct v4l2_flash_config *cfg)
> +{
> +}
> +#endif
> +
> +static void mt6370_v4l2_flash_release(void *v4l2_flash)
> +{
> + v4l2_flash_release(v4l2_flash);
> +}
> +
> +static int mt6370_led_register(struct device *parent, struct mt6370_led *led,
> + struct fwnode_handle *fwnode)
> +{
> + struct led_init_data init_data = { .fwnode = fwnode };
> + struct v4l2_flash_config v4l2_config = {};
> + int ret;
> +
> + ret = devm_led_classdev_flash_register_ext(parent, &led->flash,
> + &init_data);
> + if (ret)
> + return dev_err_probe(parent, ret,
> + "Couldn't register flash %d\n", led->led_no);
> +
> + mt6370_init_v4l2_flash_config(led, &v4l2_config);
> + led->v4l2_flash = v4l2_flash_init(parent, fwnode, &led->flash,
> + &v4l2_flash_ops, &v4l2_config);
> + if (IS_ERR(led->v4l2_flash))
> + return dev_err_probe(parent, PTR_ERR(led->v4l2_flash),
> + "Failed to register %d v4l2 sd\n", led->led_no);
> +
> + return devm_add_action_or_reset(parent, mt6370_v4l2_flash_release,
> + led->v4l2_flash);
> +}
> +
> +static u32 mt6370_clamp(u32 val, u32 min, u32 max, u32 step)
> +{
> + u32 retval;
> +
> + retval = clamp_val(val, min, max);
> + if (step > 1)
> + retval = rounddown(retval - min, step) + min;
> +
> + return retval;
> +}
> +
> +static int mt6370_init_flash_properties(struct device *dev,
> + struct mt6370_led *led,
> + struct fwnode_handle *fwnode)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct led_classdev *lcdev = &flash->led_cdev;
> + struct mt6370_priv *priv = led->priv;
> + struct led_flash_setting *s;
> + u32 sources[MT6370_MAX_LEDS];
> + u32 max_ua, val;
> + int i, ret, num;
> +
> + num = fwnode_property_count_u32(fwnode, "led-sources");
> + if (num < 1)
> + return dev_err_probe(dev, -EINVAL,
> + "Not specified or wrong number of led-sources\n");
> +
> + ret = fwnode_property_read_u32_array(fwnode, "led-sources", sources, num);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < num; i++) {
> + if (sources[i] >= MT6370_MAX_LEDS)
> + return -EINVAL;
> + if (priv->leds_active & BIT(sources[i]))
> + return -EINVAL;
> + priv->leds_active |= BIT(sources[i]);
> + }
> +
> + led->led_no = num == 2 ? MT6370_LED_JOINT : sources[0];
> +
> + max_ua = num == 2 ? MT6370_ITORCH_DOUBLE_MAX_uA : MT6370_ITORCH_MAX_uA;
> + val = MT6370_ITORCH_MIN_uA;
> + ret = fwnode_property_read_u32(fwnode, "led-max-microamp", &val);
> + if (!ret)
> + val = mt6370_clamp(val, MT6370_ITORCH_MIN_uA, max_ua,
> + MT6370_ITORCH_STEP_uA);
> +
> + lcdev->max_brightness = (val - MT6370_ITORCH_MIN_uA) /
> + MT6370_ITORCH_STEP_uA + 1;
> + lcdev->brightness_set_blocking = mt6370_torch_brightness_set;
> + lcdev->flags |= LED_DEV_CAP_FLASH;
> +
> + max_ua = num == 2 ? MT6370_ISTRB_DOUBLE_MAX_uA : MT6370_ISTRB_MAX_uA;
> + val = MT6370_ISTRB_MIN_uA;
> + ret = fwnode_property_read_u32(fwnode, "flash-max-microamp", &val);
> + if (!ret)
> + val = mt6370_clamp(val, MT6370_ISTRB_MIN_uA, max_ua,
> + MT6370_ISTRB_STEP_uA);
> +
> + s = &flash->brightness;
> + s->min = MT6370_ISTRB_MIN_uA;
> + s->step = MT6370_ISTRB_STEP_uA;
> + s->val = s->max = val;
> +
> + /*
> + * Always configure to the minimum level when
> + * off to prevent flash current spikes.
> + */
> + ret = _mt6370_flash_brightness_set(flash, s->min);
> + if (ret)
> + return ret;
> +
> +
> + val = MT6370_STRBTO_MIN_US;
> + ret = fwnode_property_read_u32(fwnode, "flash-max-timeout-us", &val);
> + if (!ret)
> + val = mt6370_clamp(val, MT6370_STRBTO_MIN_US,
> + MT6370_STRBTO_MAX_US, MT6370_STRBTO_STEP_US);
> +
> + s = &flash->timeout;
> + s->min = MT6370_STRBTO_MIN_US;
> + s->step = MT6370_STRBTO_STEP_US;
> + s->val = s->max = val;
> +
> + flash->ops = &mt6370_flash_ops;
> +
> + return 0;
> +}
> +
> +static int mt6370_led_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct mt6370_priv *priv;
> + struct fwnode_handle *child;
> + size_t count;
> + int i = 0, ret;
> +
> + count = device_get_child_node_count(dev);
> + if (!count || count > MT6370_MAX_LEDS)
> + return dev_err_probe(dev, -EINVAL,
> + "No child node or node count over max led number %zu\n", count);
> +
> + priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->leds_count = count;
> + mutex_init(&priv->lock);
> +
> + priv->regmap = dev_get_regmap(dev->parent, NULL);
> + if (!priv->regmap)
> + return dev_err_probe(dev, -ENODEV, "Failed to get parent regmap\n");
> +
> + device_for_each_child_node(dev, child) {
> + struct mt6370_led *led = priv->leds + i;
> +
> + led->priv = priv;
> +
> + ret = mt6370_init_flash_properties(dev, led, child);
> + if (ret) {
> + fwnode_handle_put(child);
> + return ret;
> + }
> +
> + ret = mt6370_led_register(dev, led, child);
> + if (ret) {
> + fwnode_handle_put(child);
> + return ret;
> + }
> +
> + i++;
> + }
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mt6370_led_of_id[] = {
> + { .compatible = "mediatek,mt6370-flashlight" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, mt6370_led_of_id);
> +
> +static struct platform_driver mt6370_led_driver = {
> + .driver = {
> + .name = "mt6370-flashlight",
> + .of_match_table = mt6370_led_of_id,
> + },
> + .probe = mt6370_led_probe,
> +};
> +module_platform_driver(mt6370_led_driver);
> +
> +MODULE_AUTHOR("Alice Chen <alice_chen@richtek.com>");
> +MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
> +MODULE_DESCRIPTION("MT6370 FLASH LED Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.7.4
>

--
Lee Jones [李琼斯]