2020-09-07 10:29:49

by Gene Chen

[permalink] [raw]
Subject: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

From: Gene Chen <[email protected]>

Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
and 4-channel RGB LED support Register/Flash/Breath Mode

Signed-off-by: Gene Chen <[email protected]>
---
drivers/leds/Kconfig | 11 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-mt6360.c | 681 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 693 insertions(+)
create mode 100644 drivers/leds/leds-mt6360.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 1c181df..94a6d83 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -271,6 +271,17 @@ config LEDS_MT6323
This option enables support for on-chip LED drivers found on
Mediatek MT6323 PMIC.

+config LEDS_MT6360
+ tristate "LED Support for Mediatek MT6360 PMIC"
+ depends on LEDS_CLASS_FLASH && OF
+ depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+ depends on MFD_MT6360
+ help
+ This option enables support for dual Flash LED drivers found on
+ Mediatek MT6360 PMIC.
+ Independent current sources supply for each flash LED support torch and strobe mode.
+ Includes Low-VF and short protection.
+
config LEDS_S3C24XX
tristate "LED Support for Samsung S3C24XX GPIO LEDs"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index c2c7d7a..5596427 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -66,6 +66,7 @@ obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o
obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o
obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o
obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
+obj-$(CONFIG_LEDS_MT6360) += leds-mt6360.o
obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
obj-$(CONFIG_LEDS_NETXBIG) += leds-netxbig.o
obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o
diff --git a/drivers/leds/leds-mt6360.c b/drivers/leds/leds-mt6360.c
new file mode 100644
index 0000000..bd6fa48
--- /dev/null
+++ b/drivers/leds/leds-mt6360.c
@@ -0,0 +1,681 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright (C) 2020 MediaTek Inc.
+//
+// Author: Gene Chen <[email protected]>
+
+#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/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <media/v4l2-flash-led-class.h>
+
+enum {
+ MT6360_LED_ISNK1 = 0,
+ MT6360_LED_ISNK2,
+ MT6360_LED_ISNK3,
+ MT6360_LED_ISNK4,
+ MT6360_LED_FLASH1,
+ MT6360_LED_FLASH2,
+ MT6360_MAX_LEDS,
+};
+
+#define MT6360_REG_RGBEN 0x380
+#define MT6360_REG_ISNK(_led_no) (0x381 + (_led_no))
+#define MT6360_ISNK_ENMASK(_led_no) BIT(7 - (_led_no))
+#define MT6360_ISNK_MASK 0x1F
+#define MT6360_CHRINDSEL_MASK BIT(3)
+
+#define MT6360_REG_FLEDEN 0x37E
+#define MT6360_REG_STRBTO 0x373
+#define MT6360_REG_FLEDBASE(_id) (0x372 + 4 * (_id - MT6360_LED_FLASH1))
+#define MT6360_REG_FLEDISTRB(_id) (MT6360_REG_FLEDBASE(_id) + 2)
+#define MT6360_REG_FLEDITOR(_id) (MT6360_REG_FLEDBASE(_id) + 3)
+#define MT6360_REG_CHGSTAT2 0x3E1
+#define MT6360_REG_FLEDSTAT1 0x3E9
+#define MT6360_ITORCH_MASK GENMASK(4, 0)
+#define MT6360_ISTROBE_MASK GENMASK(6, 0)
+#define MT6360_STRBTO_MASK GENMASK(6, 0)
+#define MT6360_TORCHEN_MASK BIT(3)
+#define MT6360_STROBEN_MASK BIT(2)
+#define MT6360_FLCSEN_MASK(_id) BIT(MT6360_LED_FLASH2 - _id)
+#define MT6360_FLEDCHGVINOVP_MASK BIT(3)
+#define MT6360_FLED1STRBTO_MASK BIT(11)
+#define MT6360_FLED2STRBTO_MASK BIT(10)
+#define MT6360_FLED1STRB_MASK BIT(9)
+#define MT6360_FLED2STRB_MASK BIT(8)
+#define MT6360_FLED1SHORT_MASK BIT(7)
+#define MT6360_FLED2SHORT_MASK BIT(6)
+#define MT6360_FLEDLVF_MASK BIT(3)
+
+/* 0 means led_off, add one for dummy */
+#define MT6360_ISNK1_MAXLEVEL 13
+#define MT6360_ISNK4_MAXLEVEL 31
+
+#define MT6360_ITORCH_MIN 25000
+#define MT6360_ITORCH_STEP 12500
+#define MT6360_ITORCH_MAX 400000
+#define MT6360_ISTRB_MIN 50000
+#define MT6360_ISTRB_STEP 12500
+#define MT6360_ISTRB_MAX 1500000
+#define MT6360_STRBTO_MIN 64000
+#define MT6360_STRBTO_STEP 32000
+#define MT6360_STRBTO_MAX 2432000
+
+#define FLED_TORCH_FLAG_MASK 0x0c
+#define FLED_TORCH_FLAG_SHFT 2
+#define FLED_STROBE_FLAG_MASK 0x03
+
+#define STATE_OFF 0
+#define STATE_KEEP 1
+#define STATE_ON 2
+
+struct mt6360_led {
+ union {
+ struct led_classdev isnk;
+ struct led_classdev_flash flash;
+ };
+ struct v4l2_flash *v4l2_flash;
+ struct mt6360_priv *priv;
+ u32 led_no;
+ u32 default_state;
+};
+
+struct mt6360_priv {
+ struct device *dev;
+ struct regmap *regmap;
+ struct mt6360_led *leds[MT6360_MAX_LEDS];
+ unsigned int fled_strobe_used;
+ unsigned int fled_torch_used;
+};
+
+static int mt6360_isnk_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
+{
+ struct mt6360_led *led = container_of(lcdev, struct mt6360_led, isnk);
+ struct mt6360_priv *priv = led->priv;
+ u32 enable_mask = MT6360_ISNK_ENMASK(led->led_no);
+ u32 val = level ? MT6360_ISNK_ENMASK(led->led_no) : 0;
+ int ret;
+
+ dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
+
+ if (level) {
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_ISNK(led->led_no),
+ MT6360_ISNK_MASK, level - 1);
+ if (ret)
+ return ret;
+ }
+
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, enable_mask, val);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int mt6360_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
+{
+ struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
+ struct mt6360_priv *priv = led->priv;
+ u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
+ u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
+ u32 prev = priv->fled_torch_used, curr;
+ int ret;
+
+ dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
+ if (priv->fled_strobe_used) {
+ dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
+ return -EINVAL;
+ }
+
+ if (level)
+ curr = prev | BIT(led->led_no);
+ else
+ curr = prev & (~BIT(led->led_no));
+
+ if (curr)
+ val |= MT6360_TORCHEN_MASK;
+
+ if (level) {
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDITOR(led->led_no),
+ MT6360_ITORCH_MASK, level - 1);
+ if (ret)
+ return ret;
+ }
+
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
+ if (ret)
+ return ret;
+
+ priv->fled_torch_used = curr;
+
+ return 0;
+}
+
+static int mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct led_classdev *lcdev = &fl_cdev->led_cdev;
+
+ dev_dbg(lcdev->dev, "[%d] strobe brightness %d\n", led->led_no, brightness);
+ return 0;
+}
+
+static int _mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct mt6360_priv *priv = led->priv;
+ struct led_flash_setting *s = &fl_cdev->brightness;
+ u32 val = (brightness - s->min) / s->step;
+
+ return regmap_update_bits(priv->regmap, MT6360_REG_FLEDISTRB(led->led_no),
+ MT6360_ISTROBE_MASK, val);
+}
+
+static int mt6360_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct mt6360_priv *priv = led->priv;
+ struct led_classdev *lcdev = &fl_cdev->led_cdev;
+ struct led_flash_setting *s = &fl_cdev->brightness;
+ u32 enable_mask = MT6360_STROBEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
+ u32 val = state ? MT6360_FLCSEN_MASK(led->led_no) : 0;
+ u32 prev = priv->fled_strobe_used, curr;
+ int ret;
+
+ dev_dbg(lcdev->dev, "[%d] strobe state %d\n", led->led_no, state);
+ if (priv->fled_torch_used) {
+ dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used);
+ return -EINVAL;
+ }
+
+ if (state)
+ curr = prev | BIT(led->led_no);
+ else
+ curr = prev & (~BIT(led->led_no));
+
+ if (curr)
+ val |= MT6360_STROBEN_MASK;
+
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
+ if (ret) {
+ dev_err(lcdev->dev, "[%d] control current source %d fail\n", led->led_no, state);
+ return ret;
+ }
+
+ /* used to prevent flash current spike when torch on */
+ ret = _mt6360_strobe_brightness_set(fl_cdev, state ? s->val : s->min);
+ if (ret)
+ return ret;
+
+ if (!prev && curr)
+ usleep_range(5000, 6000);
+ else if (prev && !curr)
+ udelay(500);
+
+ priv->fled_strobe_used = curr;
+ return 0;
+}
+
+static int mt6360_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct mt6360_priv *priv = led->priv;
+
+ *state = !!(priv->fled_strobe_used & BIT(led->led_no));
+ return 0;
+}
+
+static int mt6360_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct mt6360_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, MT6360_REG_STRBTO, MT6360_STRBTO_MASK, val);
+
+}
+
+static int mt6360_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
+{
+ struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
+ struct mt6360_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, MT6360_REG_CHGSTAT2, &chg_stat);
+ if (ret)
+ return ret;
+
+ ret = regmap_raw_read(priv->regmap, MT6360_REG_FLEDSTAT1, &fled_stat, sizeof(fled_stat));
+ if (ret)
+ return ret;
+
+ if (led->led_no == MT6360_LED_FLASH1) {
+ strobe_timeout_mask = MT6360_FLED1STRBTO_MASK;
+ fled_short_mask = MT6360_FLED1SHORT_MASK;
+
+ } else {
+ strobe_timeout_mask = MT6360_FLED2STRBTO_MASK;
+ fled_short_mask = MT6360_FLED2SHORT_MASK;
+ }
+
+ if (chg_stat & MT6360_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 & MT6360_FLEDLVF_MASK)
+ rfault |= LED_FAULT_UNDER_VOLTAGE;
+
+ *fault = rfault;
+ return 0;
+}
+
+static const struct led_flash_ops mt6360_flash_ops = {
+ .flash_brightness_set = mt6360_strobe_brightness_set,
+ .strobe_set = mt6360_strobe_set,
+ .strobe_get = mt6360_strobe_get,
+ .timeout_set = mt6360_timeout_set,
+ .fault_get = mt6360_fault_get,
+};
+
+static int mt6360_isnk_init_default_state(struct mt6360_led *led)
+{
+ struct mt6360_priv *priv = led->priv;
+ unsigned int regval;
+ u32 level;
+ int ret;
+
+ ret = regmap_read(priv->regmap, MT6360_REG_ISNK(led->led_no), &regval);
+ if (ret)
+ return ret;
+ level = regval & MT6360_ISNK_MASK;
+
+ ret = regmap_read(priv->regmap, MT6360_REG_RGBEN, &regval);
+ if (ret)
+ return ret;
+
+ if (regval & MT6360_ISNK_ENMASK(led->led_no))
+ level += 1;
+ else
+ level = LED_OFF;
+
+ switch (led->default_state) {
+ case STATE_ON:
+ led->isnk.brightness = led->isnk.max_brightness;
+ break;
+ case STATE_KEEP:
+ led->isnk.brightness = min(level, led->isnk.max_brightness);
+ break;
+ default:
+ led->isnk.brightness = LED_OFF;
+ }
+
+ return mt6360_isnk_brightness_set(&led->isnk, led->isnk.brightness);
+}
+
+static int mt6360_isnk_register(struct device *parent, struct mt6360_led *led,
+ struct led_init_data *init_data)
+{
+ struct mt6360_priv *priv = led->priv;
+ int ret;
+
+ if (led->led_no == MT6360_LED_ISNK1) {
+ /* change isink to sw mode */
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, MT6360_CHRINDSEL_MASK,
+ MT6360_CHRINDSEL_MASK);
+ if (ret) {
+ dev_err(parent, "Failed to config ISNK1 to SW mode\n");
+ return ret;
+ }
+ }
+
+ ret = mt6360_isnk_init_default_state(led);
+ if (ret) {
+ dev_err(parent, "Failed to init %d isnk state\n", led->led_no);
+ return ret;
+ }
+
+ ret = devm_led_classdev_register_ext(parent, &led->isnk, init_data);
+ if (ret) {
+ dev_err(parent, "Couldn't register isink %d\n", led->led_no);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int mt6360_flash_init_default_state(struct mt6360_led *led)
+{
+ struct led_classdev_flash *flash = &led->flash;
+ struct mt6360_priv *priv = led->priv;
+ u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
+ u32 level;
+ unsigned int regval;
+ int ret;
+
+ ret = regmap_read(priv->regmap, MT6360_REG_FLEDITOR(led->led_no), &regval);
+ if (ret)
+ return ret;
+ level = regval & MT6360_ITORCH_MASK;
+
+ ret = regmap_read(priv->regmap, MT6360_REG_FLEDEN, &regval);
+ if (ret)
+ return ret;
+
+ if ((regval & enable_mask) == enable_mask)
+ level += 1;
+ else
+ level = LED_OFF;
+
+ switch (led->default_state) {
+ case STATE_ON:
+ flash->led_cdev.brightness = flash->led_cdev.max_brightness;
+ break;
+ case STATE_KEEP:
+ flash->led_cdev.brightness = min(level, flash->led_cdev.max_brightness);
+ break;
+ default:
+ flash->led_cdev.brightness = LED_OFF;
+ }
+
+ return mt6360_torch_brightness_set(&flash->led_cdev, flash->led_cdev.brightness);
+}
+
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+static int mt6360_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
+{
+ struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
+ struct mt6360_led *led = container_of(flash, struct mt6360_led, flash);
+ struct mt6360_priv *priv = led->priv;
+ u32 enable_mask = MT6360_FLCSEN_MASK(led->led_no);
+ int ret;
+
+ ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask,
+ enable ? enable_mask : 0);
+ if (ret)
+ return ret;
+
+ if (enable)
+ priv->fled_strobe_used |= BIT(led->led_no);
+ else
+ priv->fled_strobe_used &= (~BIT(led->led_no));
+
+ return 0;
+}
+
+static const struct v4l2_flash_ops v4l2_flash_ops = {
+ .external_strobe_set = mt6360_flash_external_strobe_set,
+};
+
+static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
+{
+ struct led_classdev_flash *flash = &led->flash;
+ struct led_classdev *lcdev = &flash->led_cdev;
+ struct led_flash_setting *s = &config->intensity;
+
+ snprintf(config->dev_name, sizeof(config->dev_name), "%s", lcdev->name);
+
+ s->min = MT6360_ITORCH_MIN;
+ s->step = MT6360_ITORCH_STEP;
+ s->val = s->max = (s->min) + (lcdev->max_brightness - 1) * s->step;
+
+ config->has_external_strobe = 1;
+}
+#else
+static const struct v4l2_flash_ops v4l2_flash_ops;
+
+static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
+{
+}
+#endif
+
+static int mt6360_flash_register(struct device *parent, struct mt6360_led *led,
+ struct led_init_data *init_data)
+{
+ struct v4l2_flash_config v4l2_config = {0};
+ int ret;
+
+ ret = mt6360_flash_init_default_state(led);
+ if (ret) {
+ dev_err(parent, "Failed to init %d flash state\n", led->led_no);
+ return ret;
+ }
+
+ ret = devm_led_classdev_flash_register_ext(parent, &led->flash, init_data);
+ if (ret) {
+ dev_err(parent, "Couldn't register flash %d\n", led->led_no);
+ return ret;
+ }
+
+ mt6360_flash_init_v4l2_config(led, &v4l2_config);
+ led->v4l2_flash = v4l2_flash_init(parent, init_data->fwnode, &led->flash, &v4l2_flash_ops,
+ &v4l2_config);
+ if (IS_ERR(led->v4l2_flash)) {
+ dev_err(parent, "Failed to register %d v4l2 sd\n", led->led_no);
+ return PTR_ERR(led->v4l2_flash);
+ }
+
+ return 0;
+}
+
+static int mt6360_init_isnk_properties(struct mt6360_led *led, struct led_init_data *init_data)
+{
+ struct led_classdev *isnk = &led->isnk;
+
+ if (led->led_no == MT6360_LED_ISNK4)
+ isnk->max_brightness = MT6360_ISNK4_MAXLEVEL;
+ else
+ isnk->max_brightness = MT6360_ISNK1_MAXLEVEL;
+
+ isnk->brightness_set_blocking = mt6360_isnk_brightness_set;
+
+ fwnode_property_read_string(init_data->fwnode, "linux,default-trigger",
+ &isnk->default_trigger);
+
+ return 0;
+}
+
+static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
+{
+ *v = clamp_val(*v, min, max);
+ if (step > 1)
+ *v = (*v - min) / step * step + min;
+}
+
+static int mt6360_init_flash_properties(struct mt6360_led *led, struct led_init_data *init_data)
+{
+ struct led_classdev_flash *flash = &led->flash;
+ struct led_classdev *lcdev = &flash->led_cdev;
+ struct led_flash_setting *s;
+ u32 val;
+ int ret;
+
+ ret = fwnode_property_read_u32(init_data->fwnode, "led-max-microamp", &val);
+ if (ret)
+ val = MT6360_ITORCH_MIN;
+ else
+ clamp_align(&val, MT6360_ITORCH_MIN, MT6360_ITORCH_MAX, MT6360_ITORCH_STEP);
+
+ lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;
+ lcdev->brightness_set_blocking = mt6360_torch_brightness_set;
+ lcdev->flags |= LED_DEV_CAP_FLASH;
+
+ ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-microamp", &val);
+ if (ret)
+ val = MT6360_ISTRB_MIN;
+ else
+ clamp_align(&val, MT6360_ISTRB_MIN, MT6360_ISTRB_MAX, MT6360_ISTRB_STEP);
+
+ s = &flash->brightness;
+ s->min = MT6360_ISTRB_MIN;
+ s->step = MT6360_ISTRB_STEP;
+ s->val = s->max = val;
+
+ /* always configure as min level when off to prevent flash current spike */
+ ret = _mt6360_strobe_brightness_set(flash, s->min);
+ if (ret)
+ return ret;
+
+ ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-timeout-us", &val);
+ if (ret)
+ val = MT6360_STRBTO_MIN;
+ else
+ clamp_align(&val, MT6360_STRBTO_MIN, MT6360_STRBTO_MAX, MT6360_STRBTO_STEP);
+
+ s = &flash->timeout;
+ s->min = MT6360_STRBTO_MIN;
+ s->step = MT6360_STRBTO_STEP;
+ s->val = s->max = val;
+
+ flash->ops = &mt6360_flash_ops;
+
+ return 0;
+}
+
+static int mt6360_init_common_properties(struct mt6360_led *led, struct led_init_data *init_data)
+{
+ const char *str;
+
+ if (!fwnode_property_read_string(init_data->fwnode, "default-state", &str)) {
+ if (!strcmp(str, "on"))
+ led->default_state = STATE_ON;
+ else if (!strcmp(str, "keep"))
+ led->default_state = STATE_KEEP;
+ else
+ led->default_state = STATE_OFF;
+ }
+
+ return 0;
+}
+
+static int mt6360_led_probe(struct platform_device *pdev)
+{
+ struct mt6360_priv *priv;
+ struct fwnode_handle *child;
+ int i, ret;
+
+ ret = device_get_child_node_count(&pdev->dev);
+ if (!ret || ret > MT6360_MAX_LEDS)
+ return -EINVAL;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = &pdev->dev;
+
+ priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!priv->regmap) {
+ dev_err(&pdev->dev, "Failed to get parent regmap\n");
+ return -ENODEV;
+ }
+
+ device_for_each_child_node(&pdev->dev, child) {
+ struct mt6360_led *led;
+ struct led_init_data init_data = { .fwnode = child, };
+ u32 reg;
+
+ ret = fwnode_property_read_u32(child, "reg", &reg);
+ if (ret || reg >= MT6360_MAX_LEDS || priv->leds[reg]) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
+ if (!led) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ led->led_no = reg;
+ led->priv = priv;
+
+ ret = mt6360_init_common_properties(led, &init_data);
+ if (ret)
+ goto out;
+
+ switch (reg) {
+ case MT6360_LED_ISNK1 ... MT6360_LED_ISNK4:
+ ret = mt6360_init_isnk_properties(led, &init_data);
+ if (ret)
+ goto out;
+
+ ret = mt6360_isnk_register(&pdev->dev, led, &init_data);
+ break;
+ default:
+ ret = mt6360_init_flash_properties(led, &init_data);
+ if (ret)
+ goto out;
+
+ ret = mt6360_flash_register(&pdev->dev, led, &init_data);
+ }
+
+ if (ret)
+ goto out;
+
+ priv->leds[reg] = led;
+ }
+
+ platform_set_drvdata(pdev, priv);
+ return 0;
+out:
+ for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
+ struct mt6360_led *led = priv->leds[i];
+
+ if (led && led->v4l2_flash)
+ v4l2_flash_release(led->v4l2_flash);
+
+ }
+
+ return ret;
+}
+
+static int mt6360_led_remove(struct platform_device *pdev)
+{
+ struct mt6360_priv *priv = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
+ struct mt6360_led *led = priv->leds[i];
+
+ if (led && led->v4l2_flash)
+ v4l2_flash_release(led->v4l2_flash);
+
+ }
+
+ return 0;
+}
+
+static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
+ { .compatible = "mediatek,mt6360-led", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mt6360_led_of_id);
+
+static struct platform_driver mt6360_led_driver = {
+ .driver = {
+ .name = "mt6360-led",
+ .of_match_table = mt6360_led_of_id,
+ },
+ .probe = mt6360_led_probe,
+ .remove = mt6360_led_remove,
+};
+module_platform_driver(mt6360_led_driver);
+
+MODULE_AUTHOR("Gene Chen <[email protected]>");
+MODULE_DESCRIPTION("MT6360 Led Driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4


2020-09-08 17:24:21

by Dan Murphy

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Gene

On 9/7/20 5:27 AM, Gene Chen wrote:
> From: Gene Chen <[email protected]>
>
> Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> and 4-channel RGB LED support Register/Flash/Breath Mode
>
> Signed-off-by: Gene Chen <[email protected]>
> ---
> drivers/leds/Kconfig | 11 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-mt6360.c | 681 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 693 insertions(+)
> create mode 100644 drivers/leds/leds-mt6360.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 1c181df..94a6d83 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -271,6 +271,17 @@ config LEDS_MT6323
> This option enables support for on-chip LED drivers found on
> Mediatek MT6323 PMIC.
>
> +config LEDS_MT6360
> + tristate "LED Support for Mediatek MT6360 PMIC"
> + depends on LEDS_CLASS_FLASH && OF
> + depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
> + depends on MFD_MT6360
> + help
> + This option enables support for dual Flash LED drivers found on
> + Mediatek MT6360 PMIC.
> + Independent current sources supply for each flash LED support torch and strobe mode.
> + Includes Low-VF and short protection.
> +
> config LEDS_S3C24XX
> tristate "LED Support for Samsung S3C24XX GPIO LEDs"
> depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index c2c7d7a..5596427 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -66,6 +66,7 @@ obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o
> obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o
> obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o
> obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
> +obj-$(CONFIG_LEDS_MT6360) += leds-mt6360.o
> obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
> obj-$(CONFIG_LEDS_NETXBIG) += leds-netxbig.o
> obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o
> diff --git a/drivers/leds/leds-mt6360.c b/drivers/leds/leds-mt6360.c
> new file mode 100644
> index 0000000..bd6fa48
> --- /dev/null
> +++ b/drivers/leds/leds-mt6360.c
> @@ -0,0 +1,681 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +//
> +// Copyright (C) 2020 MediaTek Inc.
> +//
> +// Author: Gene Chen <[email protected]>
> +
> +#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/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +#include <media/v4l2-flash-led-class.h>
> +
> +enum {
> + MT6360_LED_ISNK1 = 0,
> + MT6360_LED_ISNK2,
> + MT6360_LED_ISNK3,
> + MT6360_LED_ISNK4,
> + MT6360_LED_FLASH1,
> + MT6360_LED_FLASH2,
> + MT6360_MAX_LEDS,
> +};
> +
> +#define MT6360_REG_RGBEN 0x380
> +#define MT6360_REG_ISNK(_led_no) (0x381 + (_led_no))
> +#define MT6360_ISNK_ENMASK(_led_no) BIT(7 - (_led_no))
> +#define MT6360_ISNK_MASK 0x1F
> +#define MT6360_CHRINDSEL_MASK BIT(3)
> +
> +#define MT6360_REG_FLEDEN 0x37E
> +#define MT6360_REG_STRBTO 0x373
> +#define MT6360_REG_FLEDBASE(_id) (0x372 + 4 * (_id - MT6360_LED_FLASH1))
> +#define MT6360_REG_FLEDISTRB(_id) (MT6360_REG_FLEDBASE(_id) + 2)
> +#define MT6360_REG_FLEDITOR(_id) (MT6360_REG_FLEDBASE(_id) + 3)
> +#define MT6360_REG_CHGSTAT2 0x3E1
> +#define MT6360_REG_FLEDSTAT1 0x3E9
> +#define MT6360_ITORCH_MASK GENMASK(4, 0)
> +#define MT6360_ISTROBE_MASK GENMASK(6, 0)
> +#define MT6360_STRBTO_MASK GENMASK(6, 0)
> +#define MT6360_TORCHEN_MASK BIT(3)
> +#define MT6360_STROBEN_MASK BIT(2)
> +#define MT6360_FLCSEN_MASK(_id) BIT(MT6360_LED_FLASH2 - _id)
> +#define MT6360_FLEDCHGVINOVP_MASK BIT(3)
> +#define MT6360_FLED1STRBTO_MASK BIT(11)
> +#define MT6360_FLED2STRBTO_MASK BIT(10)
> +#define MT6360_FLED1STRB_MASK BIT(9)
> +#define MT6360_FLED2STRB_MASK BIT(8)
> +#define MT6360_FLED1SHORT_MASK BIT(7)
> +#define MT6360_FLED2SHORT_MASK BIT(6)
> +#define MT6360_FLEDLVF_MASK BIT(3)
> +
> +/* 0 means led_off, add one for dummy */
> +#define MT6360_ISNK1_MAXLEVEL 13
> +#define MT6360_ISNK4_MAXLEVEL 31
> +
> +#define MT6360_ITORCH_MIN 25000
> +#define MT6360_ITORCH_STEP 12500
> +#define MT6360_ITORCH_MAX 400000
> +#define MT6360_ISTRB_MIN 50000
> +#define MT6360_ISTRB_STEP 12500
> +#define MT6360_ISTRB_MAX 1500000
> +#define MT6360_STRBTO_MIN 64000
> +#define MT6360_STRBTO_STEP 32000
> +#define MT6360_STRBTO_MAX 2432000
> +
> +#define FLED_TORCH_FLAG_MASK 0x0c
> +#define FLED_TORCH_FLAG_SHFT 2
> +#define FLED_STROBE_FLAG_MASK 0x03
> +
> +#define STATE_OFF 0
> +#define STATE_KEEP 1
> +#define STATE_ON 2
> +
> +struct mt6360_led {
> + union {
> + struct led_classdev isnk;
> + struct led_classdev_flash flash;
> + };
> + struct v4l2_flash *v4l2_flash;
> + struct mt6360_priv *priv;
> + u32 led_no;
> + u32 default_state;
> +};
> +
> +struct mt6360_priv {
> + struct device *dev;
> + struct regmap *regmap;
> + struct mt6360_led *leds[MT6360_MAX_LEDS];

I would prefer to use a flexible array here as you are not guaranteed
that the DT will contain 6 LED entries and it will simplify your probe
and DT parsing.

There are examples of using the flexible array

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/leds/leds-cr0014114.c

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/leds/leds-lm3697.c

> + unsigned int fled_strobe_used;
> + unsigned int fled_torch_used;
> +};
> +
> +static int mt6360_isnk_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> +{
> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, isnk);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_ISNK_ENMASK(led->led_no);
> + u32 val = level ? MT6360_ISNK_ENMASK(led->led_no) : 0;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> +
> + if (level) {
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_ISNK(led->led_no),
> + MT6360_ISNK_MASK, level - 1);
> + if (ret)
> + return ret;
> + }
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, enable_mask, val);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int mt6360_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> +{
> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> + u32 prev = priv->fled_torch_used, curr;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> + if (priv->fled_strobe_used) {
> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> + return -EINVAL;
> + }
> +
> + if (level)
> + curr = prev | BIT(led->led_no);
> + else
> + curr = prev & (~BIT(led->led_no));
> +
> + if (curr)
> + val |= MT6360_TORCHEN_MASK;
> +
> + if (level) {
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDITOR(led->led_no),
> + MT6360_ITORCH_MASK, level - 1);
> + if (ret)
> + return ret;
> + }
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
> + if (ret)
> + return ret;
> +
> + priv->fled_torch_used = curr;
> +
> + return 0;
> +}
> +
> +static int mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> +
> + dev_dbg(lcdev->dev, "[%d] strobe brightness %d\n", led->led_no, brightness);
> + return 0;
> +}
> +
> +static int _mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + struct led_flash_setting *s = &fl_cdev->brightness;
> + u32 val = (brightness - s->min) / s->step;
> +
> + return regmap_update_bits(priv->regmap, MT6360_REG_FLEDISTRB(led->led_no),
> + MT6360_ISTROBE_MASK, val);
> +}
> +
> +static int mt6360_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> + struct led_flash_setting *s = &fl_cdev->brightness;
> + u32 enable_mask = MT6360_STROBEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 val = state ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> + u32 prev = priv->fled_strobe_used, curr;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] strobe state %d\n", led->led_no, state);
> + if (priv->fled_torch_used) {
> + dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used);
> + return -EINVAL;
> + }
> +
> + if (state)
> + curr = prev | BIT(led->led_no);
> + else
> + curr = prev & (~BIT(led->led_no));
> +
> + if (curr)
> + val |= MT6360_STROBEN_MASK;
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
> + if (ret) {
> + dev_err(lcdev->dev, "[%d] control current source %d fail\n", led->led_no, state);
> + return ret;
> + }
> +
> + /* used to prevent flash current spike when torch on */
> + ret = _mt6360_strobe_brightness_set(fl_cdev, state ? s->val : s->min);
> + if (ret)
> + return ret;
> +
> + if (!prev && curr)
> + usleep_range(5000, 6000);
> + else if (prev && !curr)
> + udelay(500);
> +
> + priv->fled_strobe_used = curr;
> + return 0;
> +}
> +
> +static int mt6360_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> +
> + *state = !!(priv->fled_strobe_used & BIT(led->led_no));
> + return 0;
> +}
> +
> +static int mt6360_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_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, MT6360_REG_STRBTO, MT6360_STRBTO_MASK, val);
> +
> +}
> +
> +static int mt6360_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_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, MT6360_REG_CHGSTAT2, &chg_stat);
> + if (ret)
> + return ret;
> +
> + ret = regmap_raw_read(priv->regmap, MT6360_REG_FLEDSTAT1, &fled_stat, sizeof(fled_stat));
> + if (ret)
> + return ret;
> +
> + if (led->led_no == MT6360_LED_FLASH1) {
> + strobe_timeout_mask = MT6360_FLED1STRBTO_MASK;
> + fled_short_mask = MT6360_FLED1SHORT_MASK;
> +
> + } else {
> + strobe_timeout_mask = MT6360_FLED2STRBTO_MASK;
> + fled_short_mask = MT6360_FLED2SHORT_MASK;
> + }
> +
> + if (chg_stat & MT6360_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 & MT6360_FLEDLVF_MASK)
> + rfault |= LED_FAULT_UNDER_VOLTAGE;
> +
> + *fault = rfault;
> + return 0;
> +}
> +
> +static const struct led_flash_ops mt6360_flash_ops = {
> + .flash_brightness_set = mt6360_strobe_brightness_set,
> + .strobe_set = mt6360_strobe_set,
> + .strobe_get = mt6360_strobe_get,
> + .timeout_set = mt6360_timeout_set,
> + .fault_get = mt6360_fault_get,
> +};
> +
> +static int mt6360_isnk_init_default_state(struct mt6360_led *led)
> +{
> + struct mt6360_priv *priv = led->priv;
> + unsigned int regval;
> + u32 level;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_ISNK(led->led_no), &regval);
> + if (ret)
> + return ret;
> + level = regval & MT6360_ISNK_MASK;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_RGBEN, &regval);
> + if (ret)
> + return ret;
> +
> + if (regval & MT6360_ISNK_ENMASK(led->led_no))
> + level += 1;
> + else
> + level = LED_OFF;
> +
> + switch (led->default_state) {
> + case STATE_ON:
> + led->isnk.brightness = led->isnk.max_brightness;
> + break;
> + case STATE_KEEP:
> + led->isnk.brightness = min(level, led->isnk.max_brightness);
> + break;
> + default:
> + led->isnk.brightness = LED_OFF;
> + }
> +
> + return mt6360_isnk_brightness_set(&led->isnk, led->isnk.brightness);
> +}
> +
> +static int mt6360_isnk_register(struct device *parent, struct mt6360_led *led,
> + struct led_init_data *init_data)
> +{
> + struct mt6360_priv *priv = led->priv;
> + int ret;
> +
> + if (led->led_no == MT6360_LED_ISNK1) {
> + /* change isink to sw mode */
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, MT6360_CHRINDSEL_MASK,
> + MT6360_CHRINDSEL_MASK);
> + if (ret) {
> + dev_err(parent, "Failed to config ISNK1 to SW mode\n");
> + return ret;
> + }
> + }
> +
> + ret = mt6360_isnk_init_default_state(led);
> + if (ret) {
> + dev_err(parent, "Failed to init %d isnk state\n", led->led_no);
> + return ret;
> + }
> +
> + ret = devm_led_classdev_register_ext(parent, &led->isnk, init_data);
> + if (ret) {
> + dev_err(parent, "Couldn't register isink %d\n", led->led_no);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_flash_init_default_state(struct mt6360_led *led)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 level;
> + unsigned int regval;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_FLEDITOR(led->led_no), &regval);
> + if (ret)
> + return ret;
> + level = regval & MT6360_ITORCH_MASK;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_FLEDEN, &regval);
> + if (ret)
> + return ret;
> +
> + if ((regval & enable_mask) == enable_mask)
> + level += 1;
> + else
> + level = LED_OFF;
> +
> + switch (led->default_state) {
> + case STATE_ON:
> + flash->led_cdev.brightness = flash->led_cdev.max_brightness;
> + break;
> + case STATE_KEEP:
> + flash->led_cdev.brightness = min(level, flash->led_cdev.max_brightness);
> + break;
> + default:
> + flash->led_cdev.brightness = LED_OFF;
> + }
> +
> + return mt6360_torch_brightness_set(&flash->led_cdev, flash->led_cdev.brightness);
> +}
> +
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +static int mt6360_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
> +{
> + struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
> + struct mt6360_led *led = container_of(flash, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_FLCSEN_MASK(led->led_no);
> + int ret;
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask,
> + enable ? enable_mask : 0);
> + if (ret)
> + return ret;
> +
> + if (enable)
> + priv->fled_strobe_used |= BIT(led->led_no);
> + else
> + priv->fled_strobe_used &= (~BIT(led->led_no));
> +
> + return 0;
> +}
> +
> +static const struct v4l2_flash_ops v4l2_flash_ops = {
> + .external_strobe_set = mt6360_flash_external_strobe_set,
> +};
> +
> +static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct led_classdev *lcdev = &flash->led_cdev;
> + struct led_flash_setting *s = &config->intensity;
> +
> + snprintf(config->dev_name, sizeof(config->dev_name), "%s", lcdev->name);
> +
> + s->min = MT6360_ITORCH_MIN;
> + s->step = MT6360_ITORCH_STEP;
> + s->val = s->max = (s->min) + (lcdev->max_brightness - 1) * s->step;
> +
> + config->has_external_strobe = 1;
> +}
> +#else
> +static const struct v4l2_flash_ops v4l2_flash_ops;
> +
> +static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
> +{
> +}
> +#endif
> +
> +static int mt6360_flash_register(struct device *parent, struct mt6360_led *led,
> + struct led_init_data *init_data)
> +{
> + struct v4l2_flash_config v4l2_config = {0};
> + int ret;
> +
> + ret = mt6360_flash_init_default_state(led);
> + if (ret) {
> + dev_err(parent, "Failed to init %d flash state\n", led->led_no);
> + return ret;
> + }
> +
> + ret = devm_led_classdev_flash_register_ext(parent, &led->flash, init_data);
> + if (ret) {
> + dev_err(parent, "Couldn't register flash %d\n", led->led_no);
> + return ret;
> + }
> +
> + mt6360_flash_init_v4l2_config(led, &v4l2_config);
> + led->v4l2_flash = v4l2_flash_init(parent, init_data->fwnode, &led->flash, &v4l2_flash_ops,
> + &v4l2_config);
> + if (IS_ERR(led->v4l2_flash)) {
> + dev_err(parent, "Failed to register %d v4l2 sd\n", led->led_no);
> + return PTR_ERR(led->v4l2_flash);
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_init_isnk_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + struct led_classdev *isnk = &led->isnk;
> +
> + if (led->led_no == MT6360_LED_ISNK4)
> + isnk->max_brightness = MT6360_ISNK4_MAXLEVEL;
> + else
> + isnk->max_brightness = MT6360_ISNK1_MAXLEVEL;
> +
> + isnk->brightness_set_blocking = mt6360_isnk_brightness_set;
> +
> + fwnode_property_read_string(init_data->fwnode, "linux,default-trigger",
> + &isnk->default_trigger);
> +
> + return 0;
> +}
> +
> +static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
> +{
> + *v = clamp_val(*v, min, max);
> + if (step > 1)
> + *v = (*v - min) / step * step + min;
> +}
> +
> +static int mt6360_init_flash_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct led_classdev *lcdev = &flash->led_cdev;
> + struct led_flash_setting *s;
> + u32 val;
> + int ret;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "led-max-microamp", &val);
> + if (ret)
> + val = MT6360_ITORCH_MIN;
> + else
> + clamp_align(&val, MT6360_ITORCH_MIN, MT6360_ITORCH_MAX, MT6360_ITORCH_STEP);
> +
> + lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;
> + lcdev->brightness_set_blocking = mt6360_torch_brightness_set;
> + lcdev->flags |= LED_DEV_CAP_FLASH;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-microamp", &val);
> + if (ret)
> + val = MT6360_ISTRB_MIN;
> + else
> + clamp_align(&val, MT6360_ISTRB_MIN, MT6360_ISTRB_MAX, MT6360_ISTRB_STEP);
> +
> + s = &flash->brightness;
> + s->min = MT6360_ISTRB_MIN;
> + s->step = MT6360_ISTRB_STEP;
> + s->val = s->max = val;
> +
> + /* always configure as min level when off to prevent flash current spike */
> + ret = _mt6360_strobe_brightness_set(flash, s->min);
> + if (ret)
> + return ret;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-timeout-us", &val);
> + if (ret)
> + val = MT6360_STRBTO_MIN;
> + else
> + clamp_align(&val, MT6360_STRBTO_MIN, MT6360_STRBTO_MAX, MT6360_STRBTO_STEP);
> +
> + s = &flash->timeout;
> + s->min = MT6360_STRBTO_MIN;
> + s->step = MT6360_STRBTO_STEP;
> + s->val = s->max = val;
> +
> + flash->ops = &mt6360_flash_ops;
> +
> + return 0;
> +}
> +
> +static int mt6360_init_common_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + const char *str;
> +
> + if (!fwnode_property_read_string(init_data->fwnode, "default-state", &str)) {
> + if (!strcmp(str, "on"))
> + led->default_state = STATE_ON;
> + else if (!strcmp(str, "keep"))
> + led->default_state = STATE_KEEP;
> + else
> + led->default_state = STATE_OFF;
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_led_probe(struct platform_device *pdev)
> +{
> + struct mt6360_priv *priv;
> + struct fwnode_handle *child;
> + int i, ret;
> +
> + ret = device_get_child_node_count(&pdev->dev);
> + if (!ret || ret > MT6360_MAX_LEDS)
> + return -EINVAL;
> +
> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->dev = &pdev->dev;
> +
> + priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!priv->regmap) {
> + dev_err(&pdev->dev, "Failed to get parent regmap\n");
> + return -ENODEV;
> + }
> +
> + device_for_each_child_node(&pdev->dev, child) {
> + struct mt6360_led *led;
> + struct led_init_data init_data = { .fwnode = child, };
> + u32 reg;
> +
> + ret = fwnode_property_read_u32(child, "reg", &reg);
> + if (ret || reg >= MT6360_MAX_LEDS || priv->leds[reg]) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);

Using the flexible array in the mt6360_priv will eliminate this allocation.

Dan

2020-09-08 22:27:28

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi!

> From: Gene Chen <[email protected]>
>
> Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> and 4-channel RGB LED support Register/Flash/Breath Mode
>
> Signed-off-by: Gene Chen <[email protected]>
> ---
> drivers/leds/Kconfig | 11 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-mt6360.c | 681 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 693 insertions(+)
> create mode 100644 drivers/leds/leds-mt6360.c
>
> + help
> + This option enables support for dual Flash LED drivers found on
> + Mediatek MT6360 PMIC.
> + Independent current sources supply for each flash LED support torch and strobe mode.
> + Includes Low-VF and short protection.
> +

80 columns. And perhaps user does not need to know about protections... and actually
about independend sources, either.

"Enable this for RGB LED and flash LED support on..."?

> +static int mt6360_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> +{
> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> + u32 prev = priv->fled_torch_used, curr;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> + if (priv->fled_strobe_used) {
> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> + return -EINVAL;
> + }

So... how does its userland interface look like?

Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2020-09-09 16:23:21

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On Mon, Sep 7, 2020 at 1:31 PM Gene Chen <[email protected]> wrote:
>
> From: Gene Chen <[email protected]>
>
> Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> and 4-channel RGB LED support Register/Flash/Breath Mode

I'm wondering why you don't use struct led_classdev_flash.

...

> +//
> +// Copyright (C) 2020 MediaTek Inc.
> +//

Do you really need these two // lines?

...

> +enum {
> + MT6360_LED_ISNK1 = 0,
> + MT6360_LED_ISNK2,
> + MT6360_LED_ISNK3,
> + MT6360_LED_ISNK4,
> + MT6360_LED_FLASH1,
> + MT6360_LED_FLASH2,

> + MT6360_MAX_LEDS,

No comma for terminator entry.

> +};

...

> +#define MT6360_ISNK_MASK 0x1F

GENMASK()

...

> +#define MT6360_ITORCH_MIN 25000
> +#define MT6360_ITORCH_STEP 12500
> +#define MT6360_ITORCH_MAX 400000
> +#define MT6360_ISTRB_MIN 50000
> +#define MT6360_ISTRB_STEP 12500
> +#define MT6360_ISTRB_MAX 1500000
> +#define MT6360_STRBTO_MIN 64000
> +#define MT6360_STRBTO_STEP 32000
> +#define MT6360_STRBTO_MAX 2432000

Add unit suffixes, please.

...

> +#define FLED_TORCH_FLAG_MASK 0x0c

> +#define FLED_STROBE_FLAG_MASK 0x03

GENMASK()

...

> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);

Not production noise.

...

> + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, enable_mask, val);
> + if (ret)
> + return ret;
> +
> + return 0;

return regmap...

> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;

Why parens?

...

> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);

Noise.

...

> + if (priv->fled_strobe_used) {
> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> + return -EINVAL;

Hmm... Shouldn't be guaranteed by some framework?

...

> + curr = prev & (~BIT(led->led_no));

Too many parens.

...

> +static int mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> +

> + dev_dbg(lcdev->dev, "[%d] strobe brightness %d\n", led->led_no, brightness);

Noise. Point of this entire function?

> + return 0;
> +}

...

> + dev_dbg(lcdev->dev, "[%d] strobe state %d\n", led->led_no, state);

Noise.

If you wish to do it right, add trace events to the framework.

...

> + if (priv->fled_torch_used) {

> + dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used);

Again, why the warning? Can this be a part of the framework?

> + return -EINVAL;
> + }

...

> + curr = prev & (~BIT(led->led_no));

Too many parens.

...

> + if (!prev && curr)
> + usleep_range(5000, 6000);
> + else if (prev && !curr)
> + udelay(500);

These delays must be explained.

...

> + if (led->led_no == MT6360_LED_FLASH1) {
> + strobe_timeout_mask = MT6360_FLED1STRBTO_MASK;
> + fled_short_mask = MT6360_FLED1SHORT_MASK;

> +

Redundant blank line.

> + } else {
> + strobe_timeout_mask = MT6360_FLED2STRBTO_MASK;
> + fled_short_mask = MT6360_FLED2SHORT_MASK;
> + }

...

> +static int mt6360_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
> +{
> + struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
> + struct mt6360_led *led = container_of(flash, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;

> + u32 enable_mask = MT6360_FLCSEN_MASK(led->led_no);

enable_mask -> mask
u32 value = enable ? mask : 0;

> + int ret;
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask,

> + enable ? enable_mask : 0);

ret = ... mask, value);

> + if (ret)
> + return ret;
> +
> + if (enable)
> + priv->fled_strobe_used |= BIT(led->led_no);
> + else
> + priv->fled_strobe_used &= (~BIT(led->led_no));

Too many parens.

> +
> + return 0;
> +}

...

> + s->val = s->max = (s->min) + (lcdev->max_brightness - 1) * s->step;

Ditto.

...

> +static void clamp_align(u32 *v, u32 min, u32 max, u32 step)

Can we keep a similar API, i.e. return a new value rather than update old?

> +{

> + *v = clamp_val(*v, min, max);

I would rather use a temporary variable (and it actually will be
required with above).

> + if (step > 1)
> + *v = (*v - min) / step * step + min;

Sounds like open coded rounddown().

> +}

...

> + lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;

DIV_ROUND_UP(val - MT6360_ITORCH_MIN, MT6360_ITORCH_STEP) ?

...

> +static int mt6360_init_common_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + const char *str;
> +
> + if (!fwnode_property_read_string(init_data->fwnode, "default-state", &str)) {
> + if (!strcmp(str, "on"))
> + led->default_state = STATE_ON;
> + else if (!strcmp(str, "keep"))
> + led->default_state = STATE_KEEP;

> + else

I wouldn't allow some garbage to be off.

> + led->default_state = STATE_OFF;
> + }

What about

static const char * const states = { "on", "keep", "off" };

int ret;

ret = match_string(states, ARRAY_SIZE(states), str);
if (ret)
...

default_state = ret;

?

> + return 0;
> +}

...

> +static int mt6360_led_probe(struct platform_device *pdev)
> +{
> + struct mt6360_priv *priv;
> + struct fwnode_handle *child;
> + int i, ret;
> +

> + priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!priv->regmap) {
> + dev_err(&pdev->dev, "Failed to get parent regmap\n");
> + return -ENODEV;
> + }

...

> +out:

out_flash_leds_release: ?

> + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> + struct mt6360_led *led = priv->leds[i];
> +
> + if (led && led->v4l2_flash)
> + v4l2_flash_release(led->v4l2_flash);
> +
> + }

...

> +static int mt6360_led_remove(struct platform_device *pdev)
> +{
> + struct mt6360_priv *priv = platform_get_drvdata(pdev);
> + int i;
> +
> + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> + struct mt6360_led *led = priv->leds[i];
> +
> + if (led && led->v4l2_flash)
> + v4l2_flash_release(led->v4l2_flash);
> +
> + }

Looks like a code duplication.

> +
> + return 0;
> +}
> +
> +static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
> + { .compatible = "mediatek,mt6360-led", },

> + {},

No need comma.

> +};


--
With Best Regards,
Andy Shevchenko

2020-09-10 07:53:09

by Gene Chen

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Pavel Machek <[email protected]> 於 2020年9月9日 週三 上午6:25寫道:
>
> Hi!
>
> > From: Gene Chen <[email protected]>
> >
> > Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> > and 4-channel RGB LED support Register/Flash/Breath Mode
> >
> > Signed-off-by: Gene Chen <[email protected]>
> > ---
> > drivers/leds/Kconfig | 11 +
> > drivers/leds/Makefile | 1 +
> > drivers/leds/leds-mt6360.c | 681 +++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 693 insertions(+)
> > create mode 100644 drivers/leds/leds-mt6360.c
> >
> > + help
> > + This option enables support for dual Flash LED drivers found on
> > + Mediatek MT6360 PMIC.
> > + Independent current sources supply for each flash LED support torch and strobe mode.
> > + Includes Low-VF and short protection.
> > +
>
> 80 columns. And perhaps user does not need to know about protections... and actually
> about independend sources, either.
>

ACK

> "Enable this for RGB LED and flash LED support on..."?
>
> > +static int mt6360_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> > +{
> > + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> > + struct mt6360_priv *priv = led->priv;
> > + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> > + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> > + u32 prev = priv->fled_torch_used, curr;
> > + int ret;
> > +
> > + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> > + if (priv->fled_strobe_used) {
> > + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> > + return -EINVAL;
> > + }
>
> So... how does its userland interface look like?
>

1. set FLED1 brightness
# echo 1 > /sys/class/leds/white:flash1/flash_brightness
2. enable FLED1 strobe
# echo 1 > /sys/class/leds/white:flash1/flash_strobe
3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
flash leds must be turned off)
# echo 0 > /sys/class/leds/white:flash1/flash_strobe

> Best regards,
> Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2020-09-10 08:14:59

by Gene Chen

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Andy Shevchenko <[email protected]> 於 2020年9月9日 週三 下午9:48寫道:
>
> On Mon, Sep 7, 2020 at 1:31 PM Gene Chen <[email protected]> wrote:
> >
> > From: Gene Chen <[email protected]>
> >
> > Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> > and 4-channel RGB LED support Register/Flash/Breath Mode
>
> I'm wondering why you don't use struct led_classdev_flash.
>
> ...
>

Both Flash and RGB LED use led_classdev_flash by
"devm_led_classdev_flash_register_ext".

> > +//
> > +// Copyright (C) 2020 MediaTek Inc.
> > +//
>
> Do you really need these two // lines?
>

ACK, I will remove it

> ...
>
> > +enum {
> > + MT6360_LED_ISNK1 = 0,
> > + MT6360_LED_ISNK2,
> > + MT6360_LED_ISNK3,
> > + MT6360_LED_ISNK4,
> > + MT6360_LED_FLASH1,
> > + MT6360_LED_FLASH2,
>
> > + MT6360_MAX_LEDS,
>
> No comma for terminator entry.
>

ACK

> > +};
>
> ...
>
> > +#define MT6360_ISNK_MASK 0x1F
>
> GENMASK()
>
> ...
>
> > +#define MT6360_ITORCH_MIN 25000
> > +#define MT6360_ITORCH_STEP 12500
> > +#define MT6360_ITORCH_MAX 400000
> > +#define MT6360_ISTRB_MIN 50000
> > +#define MT6360_ISTRB_STEP 12500
> > +#define MT6360_ISTRB_MAX 1500000
> > +#define MT6360_STRBTO_MIN 64000
> > +#define MT6360_STRBTO_STEP 32000
> > +#define MT6360_STRBTO_MAX 2432000
>
> Add unit suffixes, please.
>

ACK

> ...
>
> > +#define FLED_TORCH_FLAG_MASK 0x0c
>
> > +#define FLED_STROBE_FLAG_MASK 0x03
>
> GENMASK()
>

ACK

> ...
>
> > + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
>
> Not production noise.
>

ACK

> ...
>
> > + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, enable_mask, val);
> > + if (ret)
> > + return ret;
> > +
> > + return 0;
>
> return regmap...
>
> > + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
>
> Why parens?
>

ACK

> ...
>
> > + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
>
> Noise.
>

ACK

> ...
>
> > + if (priv->fled_strobe_used) {
> > + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> > + return -EINVAL;
>
> Hmm... Shouldn't be guaranteed by some framework?
>

Because both Flash LED use single logically control.
It doesn't exist one LED is torch mode, and the other is strobe mode.

> ...
>
> > + curr = prev & (~BIT(led->led_no));
>
> Too many parens.
>

ACK

> ...
>
> > +static int mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)
> > +{
> > + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> > + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> > +
>
> > + dev_dbg(lcdev->dev, "[%d] strobe brightness %d\n", led->led_no, brightness);
>
> Noise. Point of this entire function?
>

ACK, I will remove it, reserve function entry only for register
ledcass_dev check ops exist

> > + return 0;
> > +}
>
> ...
>
> > + dev_dbg(lcdev->dev, "[%d] strobe state %d\n", led->led_no, state);
>
> Noise.
>
> If you wish to do it right, add trace events to the framework.
>

ACK, I will remove it.

> ...
>
> > + if (priv->fled_torch_used) {
>
> > + dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used);
>
> Again, why the warning? Can this be a part of the framework?
>

Same as above.

> > + return -EINVAL;
> > + }
>
> ...
>
> > + curr = prev & (~BIT(led->led_no));
>
> Too many parens.
>

ACK

> ...
>
> > + if (!prev && curr)
> > + usleep_range(5000, 6000);
> > + else if (prev && !curr)
> > + udelay(500);
>
> These delays must be explained.
>

ACK

> ...
>
> > + if (led->led_no == MT6360_LED_FLASH1) {
> > + strobe_timeout_mask = MT6360_FLED1STRBTO_MASK;
> > + fled_short_mask = MT6360_FLED1SHORT_MASK;
>
> > +
>
> Redundant blank line.
>

ACK

> > + } else {
> > + strobe_timeout_mask = MT6360_FLED2STRBTO_MASK;
> > + fled_short_mask = MT6360_FLED2SHORT_MASK;
> > + }
>
> ...
>
> > +static int mt6360_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
> > +{
> > + struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
> > + struct mt6360_led *led = container_of(flash, struct mt6360_led, flash);
> > + struct mt6360_priv *priv = led->priv;
>
> > + u32 enable_mask = MT6360_FLCSEN_MASK(led->led_no);
>
> enable_mask -> mask
> u32 value = enable ? mask : 0;
>
> > + int ret;
> > +
> > + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask,
>
> > + enable ? enable_mask : 0);
>
> ret = ... mask, value);
>

ACK

> > + if (ret)
> > + return ret;
> > +
> > + if (enable)
> > + priv->fled_strobe_used |= BIT(led->led_no);
> > + else
> > + priv->fled_strobe_used &= (~BIT(led->led_no));
>
> Too many parens.
>

ACK

> > +
> > + return 0;
> > +}
>
> ...
>
> > + s->val = s->max = (s->min) + (lcdev->max_brightness - 1) * s->step;
>
> Ditto.
>

ACK

> ...
>
> > +static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
>
> Can we keep a similar API, i.e. return a new value rather than update old?
>
> > +{
>
> > + *v = clamp_val(*v, min, max);
>
> I would rather use a temporary variable (and it actually will be
> required with above).
>
> > + if (step > 1)
> > + *v = (*v - min) / step * step + min;
>
> Sounds like open coded rounddown().
>

ACK

> > +}
>
> ...
>
> > + lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;
>
> DIV_ROUND_UP(val - MT6360_ITORCH_MIN, MT6360_ITORCH_STEP) ?
>

This is mapping 0~val to 1~max_brightness as level.
I convert val below MT6360_ITORCH_STEP to 1 for ignore max_brightness
= 0, because 0 means disable.
There is a little difference from DIV_ROUND_UP.

> ...
>
> > +static int mt6360_init_common_properties(struct mt6360_led *led, struct led_init_data *init_data)
> > +{
> > + const char *str;
> > +
> > + if (!fwnode_property_read_string(init_data->fwnode, "default-state", &str)) {
> > + if (!strcmp(str, "on"))
> > + led->default_state = STATE_ON;
> > + else if (!strcmp(str, "keep"))
> > + led->default_state = STATE_KEEP;
>
> > + else
>
> I wouldn't allow some garbage to be off.
>

ACK

> > + led->default_state = STATE_OFF;
> > + }
>
> What about
>
> static const char * const states = { "on", "keep", "off" };
>
> int ret;
>
> ret = match_string(states, ARRAY_SIZE(states), str);
> if (ret)
> ...
>
> default_state = ret;
>
> ?
>
> > + return 0;
> > +}
>

ACK

> ...
>
> > +static int mt6360_led_probe(struct platform_device *pdev)
> > +{
> > + struct mt6360_priv *priv;
> > + struct fwnode_handle *child;
> > + int i, ret;
> > +
>
> > + priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> > + if (!priv->regmap) {
> > + dev_err(&pdev->dev, "Failed to get parent regmap\n");
> > + return -ENODEV;
> > + }
>
> ...
>
> > +out:
>
> out_flash_leds_release: ?
>

ACK

> > + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> > + struct mt6360_led *led = priv->leds[i];
> > +
> > + if (led && led->v4l2_flash)
> > + v4l2_flash_release(led->v4l2_flash);
> > +
> > + }
>
> ...
>
> > +static int mt6360_led_remove(struct platform_device *pdev)
> > +{
> > + struct mt6360_priv *priv = platform_get_drvdata(pdev);
> > + int i;
> > +
> > + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> > + struct mt6360_led *led = priv->leds[i];
> > +
> > + if (led && led->v4l2_flash)
> > + v4l2_flash_release(led->v4l2_flash);
> > +
> > + }
>
> Looks like a code duplication.
>

ACK

> > +
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
> > + { .compatible = "mediatek,mt6360-led", },
>
> > + {},
>
> No need comma.
>

ACK

> > +};
>
>
> --
> With Best Regards,
> Andy Shevchenko

2020-09-10 08:38:07

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi!

> > > +enum {
> > > + MT6360_LED_ISNK1 = 0,
> > > + MT6360_LED_ISNK2,
> > > + MT6360_LED_ISNK3,
> > > + MT6360_LED_ISNK4,
> > > + MT6360_LED_FLASH1,
> > > + MT6360_LED_FLASH2,
> >
> > > + MT6360_MAX_LEDS,
> >
> > No comma for terminator entry.
> >
>
> ACK

Actually, that comma is fine. Its absence would be fine, too.

> > > +};
> >
> > ...
> >
> > > +#define MT6360_ISNK_MASK 0x1F
> >
> > GENMASK()

Again, that is fine.

> > > +#define FLED_TORCH_FLAG_MASK 0x0c
> >
> > > +#define FLED_STROBE_FLAG_MASK 0x03
> >
> > GENMASK()
> >
>
> ACK

Again, that is fine.

> > > + return 0;
> > > +}
> > > +
> > > +static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
> > > + { .compatible = "mediatek,mt6360-led", },
> >
> > > + {},
> >
> > No need comma.
>
> ACK

It is also no hurting comma.

Best regards,

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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2020-09-10 11:55:08

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On Thu, Sep 10, 2020 at 11:11 AM Gene Chen <[email protected]> wrote:
> Andy Shevchenko <[email protected]> 於 2020年9月9日 週三 下午9:48寫道:
> > On Mon, Sep 7, 2020 at 1:31 PM Gene Chen <[email protected]> wrote:
> > > From: Gene Chen <[email protected]>

...

> > > + if (priv->fled_strobe_used) {
> > > + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> > > + return -EINVAL;
> >
> > Hmm... Shouldn't be guaranteed by some framework?
> >
>
> Because both Flash LED use single logically control.
> It doesn't exist one LED is torch mode, and the other is strobe mode.

You mean you have always an attribute for hardware even if it doesn't
support a feature?
Can you consider hiding attributes?

...

> > > + lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;
> >
> > DIV_ROUND_UP(val - MT6360_ITORCH_MIN, MT6360_ITORCH_STEP) ?
> >
>
> This is mapping 0~val to 1~max_brightness as level.
> I convert val below MT6360_ITORCH_STEP to 1 for ignore max_brightness
> = 0, because 0 means disable.
> There is a little difference from DIV_ROUND_UP.

What div_round_up does is
(x + y - 1) / y
What do you do

x / y + 1 = (x + y)/y = ((x + 1) + y - 1)/y = DIV_ROUND_UP(x+1,y)

So, DIV_ROUND_UP(val - MT6360_ITORCH_MIN + 1, MT6360_ITORCH_STEP) ?

(yes I made classical off-by-one error)

--
With Best Regards,
Andy Shevchenko

2020-09-10 11:58:39

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On Thu, Sep 10, 2020 at 11:18 AM Pavel Machek <[email protected]> wrote:

...

> > > > +enum {
> > > > + MT6360_LED_ISNK1 = 0,
> > > > + MT6360_LED_ISNK2,
> > > > + MT6360_LED_ISNK3,
> > > > + MT6360_LED_ISNK4,
> > > > + MT6360_LED_FLASH1,
> > > > + MT6360_LED_FLASH2,
> > >
> > > > + MT6360_MAX_LEDS,
> > >
> > > No comma for terminator entry.
> > >
> >
> > ACK
>
> Actually, that comma is fine. Its absence would be fine, too.

It is slightly better not to have to prevent (theoretical) rebase or
other similar issues when a new item can go behind the terminator. In
such a case compiler can easily tell you if something is wrong.

> > > > +};

...

> > > > +static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
> > > > + { .compatible = "mediatek,mt6360-led", },
> > >
> > > > + {},
> > >
> > > No need comma.
> >
> > ACK
>
> It is also no hurting comma.

Same explanation. It doesn't hurt per se, but its absence might serve a purpose.

--
With Best Regards,
Andy Shevchenko

2020-09-10 12:36:27

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On Thu 2020-09-10 14:34:54, Andy Shevchenko wrote:
> On Thu, Sep 10, 2020 at 11:18 AM Pavel Machek <[email protected]> wrote:
>
> ...
>
> > > > > +enum {
> > > > > + MT6360_LED_ISNK1 = 0,
> > > > > + MT6360_LED_ISNK2,
> > > > > + MT6360_LED_ISNK3,
> > > > > + MT6360_LED_ISNK4,
> > > > > + MT6360_LED_FLASH1,
> > > > > + MT6360_LED_FLASH2,
> > > >
> > > > > + MT6360_MAX_LEDS,
> > > >
> > > > No comma for terminator entry.
> > > >
> > >
> > > ACK
> >
> > Actually, that comma is fine. Its absence would be fine, too.
>
> It is slightly better not to have to prevent (theoretical) rebase or
> other similar issues when a new item can go behind the terminator. In
> such a case compiler can easily tell you if something is wrong.

Okay, I see your point.
Pavel

--
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2020-09-10 12:39:23

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi!

> > > +{
> > > + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> > > + struct mt6360_priv *priv = led->priv;
> > > + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> > > + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> > > + u32 prev = priv->fled_torch_used, curr;
> > > + int ret;
> > > +
> > > + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> > > + if (priv->fled_strobe_used) {
> > > + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> > > + return -EINVAL;
> > > + }
> >
> > So... how does its userland interface look like?
> >
>
> 1. set FLED1 brightness
> # echo 1 > /sys/class/leds/white:flash1/flash_brightness
> 2. enable FLED1 strobe
> # echo 1 > /sys/class/leds/white:flash1/flash_strobe
> 3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
> flash leds must be turned off)
> # echo 0 > /sys/class/leds/white:flash1/flash_strobe

I believe I'd preffer only exposing torch functionality in
/sys/class/leds. .. strobe can be supported using v4l2 APIs.

Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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2020-09-10 20:28:31

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi!

> > > 1. set FLED1 brightness
> > > # echo 1 > /sys/class/leds/white:flash1/flash_brightness
> > > 2. enable FLED1 strobe
> > > # echo 1 > /sys/class/leds/white:flash1/flash_strobe
> > > 3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
> > > flash leds must be turned off)
> > > # echo 0 > /sys/class/leds/white:flash1/flash_strobe
> >
> > I believe I'd preffer only exposing torch functionality in
> > /sys/class/leds. .. strobe can be supported using v4l2 APIs.
>
> Actually having LED flash class without strobe is pointless.
> If you looked at led_classdev_flash_register_ext() you would see that
> it fails with uninitialized strobe_set op. And V4L2 API for strobing
> flash calls strobe_set from LED flash class beneath.
>
> That was the idea behind LED and V4L2 flash API unification - there
> is one hardware driver needed, the V4L2 Flash layer just takes over
> control over it when needed.

I agree that one driver is enough.

But we should not need flash_strobe file in sysfs. Simply use V4L2 for
that.

Best regards,
Pavel

2020-09-10 20:28:46

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On 9/10/20 2:29 PM, Pavel Machek wrote:
> Hi!
>
>>>> +{
>>>> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
>>>> + struct mt6360_priv *priv = led->priv;
>>>> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
>>>> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
>>>> + u32 prev = priv->fled_torch_used, curr;
>>>> + int ret;
>>>> +
>>>> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
>>>> + if (priv->fled_strobe_used) {
>>>> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
>>>> + return -EINVAL;
>>>> + }
>>>
>>> So... how does its userland interface look like?
>>>
>>
>> 1. set FLED1 brightness
>> # echo 1 > /sys/class/leds/white:flash1/flash_brightness
>> 2. enable FLED1 strobe
>> # echo 1 > /sys/class/leds/white:flash1/flash_strobe
>> 3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
>> flash leds must be turned off)
>> # echo 0 > /sys/class/leds/white:flash1/flash_strobe
>
> I believe I'd preffer only exposing torch functionality in
> /sys/class/leds. .. strobe can be supported using v4l2 APIs.

Actually having LED flash class without strobe is pointless.
If you looked at led_classdev_flash_register_ext() you would see that
it fails with uninitialized strobe_set op. And V4L2 API for strobing
flash calls strobe_set from LED flash class beneath.

That was the idea behind LED and V4L2 flash API unification - there
is one hardware driver needed, the V4L2 Flash layer just takes over
control over it when needed.

--
Best regards,
Jacek Anaszewski

2020-09-10 20:38:01

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On 9/10/20 10:25 PM, Pavel Machek wrote:
> Hi!
>
>>>> 1. set FLED1 brightness
>>>> # echo 1 > /sys/class/leds/white:flash1/flash_brightness
>>>> 2. enable FLED1 strobe
>>>> # echo 1 > /sys/class/leds/white:flash1/flash_strobe
>>>> 3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
>>>> flash leds must be turned off)
>>>> # echo 0 > /sys/class/leds/white:flash1/flash_strobe
>>>
>>> I believe I'd preffer only exposing torch functionality in
>>> /sys/class/leds. .. strobe can be supported using v4l2 APIs.
>>
>> Actually having LED flash class without strobe is pointless.
>> If you looked at led_classdev_flash_register_ext() you would see that
>> it fails with uninitialized strobe_set op. And V4L2 API for strobing
>> flash calls strobe_set from LED flash class beneath.
>>
>> That was the idea behind LED and V4L2 flash API unification - there
>> is one hardware driver needed, the V4L2 Flash layer just takes over
>> control over it when needed.
>
> I agree that one driver is enough.
>
> But we should not need flash_strobe file in sysfs. Simply use V4L2 for
> that.

Apart from the fact that we can't remove it from LED flash class ABI
now, why would you like to prevent the user from exploiting main feature
of the hardware?

--
Best regards,
Jacek Anaszewski

2020-09-10 21:56:54

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi Gene,

Thanks for the update.

On 9/7/20 12:27 PM, Gene Chen wrote:
> From: Gene Chen <[email protected]>
>
> Add MT6360 LED driver include 2-channel Flash LED with torch/strobe mode,
> and 4-channel RGB LED support Register/Flash/Breath Mode
>
> Signed-off-by: Gene Chen <[email protected]>
> ---
> drivers/leds/Kconfig | 11 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-mt6360.c | 681 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 693 insertions(+)
> create mode 100644 drivers/leds/leds-mt6360.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 1c181df..94a6d83 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -271,6 +271,17 @@ config LEDS_MT6323
> This option enables support for on-chip LED drivers found on
> Mediatek MT6323 PMIC.
>
> +config LEDS_MT6360
> + tristate "LED Support for Mediatek MT6360 PMIC"
> + depends on LEDS_CLASS_FLASH && OF
> + depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
> + depends on MFD_MT6360
> + help
> + This option enables support for dual Flash LED drivers found on
> + Mediatek MT6360 PMIC.
> + Independent current sources supply for each flash LED support torch and strobe mode.
> + Includes Low-VF and short protection.
> +
> config LEDS_S3C24XX
> tristate "LED Support for Samsung S3C24XX GPIO LEDs"
> depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index c2c7d7a..5596427 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -66,6 +66,7 @@ obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o
> obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o
> obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o
> obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
> +obj-$(CONFIG_LEDS_MT6360) += leds-mt6360.o
> obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
> obj-$(CONFIG_LEDS_NETXBIG) += leds-netxbig.o
> obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o
> diff --git a/drivers/leds/leds-mt6360.c b/drivers/leds/leds-mt6360.c
> new file mode 100644
> index 0000000..bd6fa48
> --- /dev/null
> +++ b/drivers/leds/leds-mt6360.c
> @@ -0,0 +1,681 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +//
> +// Copyright (C) 2020 MediaTek Inc.
> +//
> +// Author: Gene Chen <[email protected]>
> +
> +#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/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +#include <media/v4l2-flash-led-class.h>
> +
> +enum {
> + MT6360_LED_ISNK1 = 0,
> + MT6360_LED_ISNK2,
> + MT6360_LED_ISNK3,
> + MT6360_LED_ISNK4,
> + MT6360_LED_FLASH1,
> + MT6360_LED_FLASH2,
> + MT6360_MAX_LEDS,
> +};
> +
> +#define MT6360_REG_RGBEN 0x380
> +#define MT6360_REG_ISNK(_led_no) (0x381 + (_led_no))
> +#define MT6360_ISNK_ENMASK(_led_no) BIT(7 - (_led_no))
> +#define MT6360_ISNK_MASK 0x1F
> +#define MT6360_CHRINDSEL_MASK BIT(3)
> +
> +#define MT6360_REG_FLEDEN 0x37E
> +#define MT6360_REG_STRBTO 0x373
> +#define MT6360_REG_FLEDBASE(_id) (0x372 + 4 * (_id - MT6360_LED_FLASH1))
> +#define MT6360_REG_FLEDISTRB(_id) (MT6360_REG_FLEDBASE(_id) + 2)
> +#define MT6360_REG_FLEDITOR(_id) (MT6360_REG_FLEDBASE(_id) + 3)
> +#define MT6360_REG_CHGSTAT2 0x3E1
> +#define MT6360_REG_FLEDSTAT1 0x3E9
> +#define MT6360_ITORCH_MASK GENMASK(4, 0)
> +#define MT6360_ISTROBE_MASK GENMASK(6, 0)
> +#define MT6360_STRBTO_MASK GENMASK(6, 0)
> +#define MT6360_TORCHEN_MASK BIT(3)
> +#define MT6360_STROBEN_MASK BIT(2)
> +#define MT6360_FLCSEN_MASK(_id) BIT(MT6360_LED_FLASH2 - _id)
> +#define MT6360_FLEDCHGVINOVP_MASK BIT(3)
> +#define MT6360_FLED1STRBTO_MASK BIT(11)
> +#define MT6360_FLED2STRBTO_MASK BIT(10)
> +#define MT6360_FLED1STRB_MASK BIT(9)
> +#define MT6360_FLED2STRB_MASK BIT(8)
> +#define MT6360_FLED1SHORT_MASK BIT(7)
> +#define MT6360_FLED2SHORT_MASK BIT(6)
> +#define MT6360_FLEDLVF_MASK BIT(3)
> +
> +/* 0 means led_off, add one for dummy */
> +#define MT6360_ISNK1_MAXLEVEL 13
> +#define MT6360_ISNK4_MAXLEVEL 31
> +
> +#define MT6360_ITORCH_MIN 25000
> +#define MT6360_ITORCH_STEP 12500
> +#define MT6360_ITORCH_MAX 400000
> +#define MT6360_ISTRB_MIN 50000
> +#define MT6360_ISTRB_STEP 12500
> +#define MT6360_ISTRB_MAX 1500000
> +#define MT6360_STRBTO_MIN 64000
> +#define MT6360_STRBTO_STEP 32000
> +#define MT6360_STRBTO_MAX 2432000
> +
> +#define FLED_TORCH_FLAG_MASK 0x0c
> +#define FLED_TORCH_FLAG_SHFT 2
> +#define FLED_STROBE_FLAG_MASK 0x03
> +
> +#define STATE_OFF 0
> +#define STATE_KEEP 1
> +#define STATE_ON 2
> +
> +struct mt6360_led {
> + union {
> + struct led_classdev isnk;
> + struct led_classdev_flash flash;
> + };
> + struct v4l2_flash *v4l2_flash;
> + struct mt6360_priv *priv;
> + u32 led_no;
> + u32 default_state;
> +};
> +
> +struct mt6360_priv {
> + struct device *dev;
> + struct regmap *regmap;
> + struct mt6360_led *leds[MT6360_MAX_LEDS];
> + unsigned int fled_strobe_used;
> + unsigned int fled_torch_used;
> +};
> +
> +static int mt6360_isnk_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> +{
> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, isnk);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_ISNK_ENMASK(led->led_no);
> + u32 val = level ? MT6360_ISNK_ENMASK(led->led_no) : 0;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> +
> + if (level) {
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_ISNK(led->led_no),
> + MT6360_ISNK_MASK, level - 1);
> + if (ret)
> + return ret;
> + }
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, enable_mask, val);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int mt6360_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> +{
> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> + u32 prev = priv->fled_torch_used, curr;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> + if (priv->fled_strobe_used) {
> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);

Doesn't hardware handle that? IOW, what happens when you have enabled
both torch and flash? If flash just overrides torch mode, than you
should not prevent enabling torch in this case.

> + return -EINVAL;
> + }
> +
> + if (level)
> + curr = prev | BIT(led->led_no);
> + else
> + curr = prev & (~BIT(led->led_no));
> +
> + if (curr)
> + val |= MT6360_TORCHEN_MASK;
> +
> + if (level) {
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDITOR(led->led_no),
> + MT6360_ITORCH_MASK, level - 1);
> + if (ret)
> + return ret;
> + }
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
> + if (ret)
> + return ret;
> +
> + priv->fled_torch_used = curr;
> +
> + return 0;
> +}
> +
> +static int mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)

s/strobe_brightness_set/flash_brightness_set/

Let's stick to the op name.

> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;

It would be good to add comment here explaining why this function
doesn't do anything.

> + dev_dbg(lcdev->dev, "[%d] strobe brightness %d\n", led->led_no, brightness);
> + return 0;
> +}
> +
> +static int _mt6360_strobe_brightness_set(struct led_classdev_flash *fl_cdev, u32 brightness)

s/strobe_brightness_set/flash_brightness_set/

> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + struct led_flash_setting *s = &fl_cdev->brightness;
> + u32 val = (brightness - s->min) / s->step;
> +
> + return regmap_update_bits(priv->regmap, MT6360_REG_FLEDISTRB(led->led_no),
> + MT6360_ISTROBE_MASK, val);
> +}
> +
> +static int mt6360_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + struct led_classdev *lcdev = &fl_cdev->led_cdev;
> + struct led_flash_setting *s = &fl_cdev->brightness;
> + u32 enable_mask = MT6360_STROBEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 val = state ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> + u32 prev = priv->fled_strobe_used, curr;
> + int ret;
> +
> + dev_dbg(lcdev->dev, "[%d] strobe state %d\n", led->led_no, state);
> + if (priv->fled_torch_used) {
> + dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n", priv->fled_torch_used);

Similar comment as in case of enabling torch mode above.
If flash overrides torch then we're OK without this guard.

> + return -EINVAL;
> + }
> +
> + if (state)
> + curr = prev | BIT(led->led_no);
> + else
> + curr = prev & (~BIT(led->led_no));
> +
> + if (curr)
> + val |= MT6360_STROBEN_MASK;
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask, val);
> + if (ret) {
> + dev_err(lcdev->dev, "[%d] control current source %d fail\n", led->led_no, state);
> + return ret;
> + }
> +
> + /* used to prevent flash current spike when torch on */
> + ret = _mt6360_strobe_brightness_set(fl_cdev, state ? s->val : s->min);
> + if (ret)
> + return ret;
> +
> + if (!prev && curr)
> + usleep_range(5000, 6000);
> + else if (prev && !curr)
> + udelay(500);
> +
> + priv->fled_strobe_used = curr;
> + return 0;
> +}
> +
> +static int mt6360_strobe_get(struct led_classdev_flash *fl_cdev, bool *state)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> +
> + *state = !!(priv->fled_strobe_used & BIT(led->led_no));
> + return 0;
> +}
> +
> +static int mt6360_timeout_set(struct led_classdev_flash *fl_cdev, u32 timeout)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_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, MT6360_REG_STRBTO, MT6360_STRBTO_MASK, val);
> +
> +}
> +
> +static int mt6360_fault_get(struct led_classdev_flash *fl_cdev, u32 *fault)
> +{
> + struct mt6360_led *led = container_of(fl_cdev, struct mt6360_led, flash);
> + struct mt6360_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, MT6360_REG_CHGSTAT2, &chg_stat);
> + if (ret)
> + return ret;
> +
> + ret = regmap_raw_read(priv->regmap, MT6360_REG_FLEDSTAT1, &fled_stat, sizeof(fled_stat));
> + if (ret)
> + return ret;
> +
> + if (led->led_no == MT6360_LED_FLASH1) {
> + strobe_timeout_mask = MT6360_FLED1STRBTO_MASK;
> + fled_short_mask = MT6360_FLED1SHORT_MASK;
> +
> + } else {
> + strobe_timeout_mask = MT6360_FLED2STRBTO_MASK;
> + fled_short_mask = MT6360_FLED2SHORT_MASK;
> + }
> +
> + if (chg_stat & MT6360_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 & MT6360_FLEDLVF_MASK)
> + rfault |= LED_FAULT_UNDER_VOLTAGE;
> +
> + *fault = rfault;
> + return 0;
> +}
> +
> +static const struct led_flash_ops mt6360_flash_ops = {
> + .flash_brightness_set = mt6360_strobe_brightness_set,
> + .strobe_set = mt6360_strobe_set,
> + .strobe_get = mt6360_strobe_get,
> + .timeout_set = mt6360_timeout_set,
> + .fault_get = mt6360_fault_get,
> +};
> +
> +static int mt6360_isnk_init_default_state(struct mt6360_led *led)
> +{
> + struct mt6360_priv *priv = led->priv;
> + unsigned int regval;
> + u32 level;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_ISNK(led->led_no), &regval);
> + if (ret)
> + return ret;
> + level = regval & MT6360_ISNK_MASK;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_RGBEN, &regval);
> + if (ret)
> + return ret;
> +
> + if (regval & MT6360_ISNK_ENMASK(led->led_no))
> + level += 1;
> + else
> + level = LED_OFF;
> +
> + switch (led->default_state) {
> + case STATE_ON:
> + led->isnk.brightness = led->isnk.max_brightness;
> + break;
> + case STATE_KEEP:
> + led->isnk.brightness = min(level, led->isnk.max_brightness);
> + break;
> + default:
> + led->isnk.brightness = LED_OFF;
> + }
> +
> + return mt6360_isnk_brightness_set(&led->isnk, led->isnk.brightness);
> +}
> +
> +static int mt6360_isnk_register(struct device *parent, struct mt6360_led *led,
> + struct led_init_data *init_data)
> +{
> + struct mt6360_priv *priv = led->priv;
> + int ret;
> +
> + if (led->led_no == MT6360_LED_ISNK1) {
> + /* change isink to sw mode */
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_RGBEN, MT6360_CHRINDSEL_MASK,
> + MT6360_CHRINDSEL_MASK);
> + if (ret) {
> + dev_err(parent, "Failed to config ISNK1 to SW mode\n");
> + return ret;
> + }
> + }
> +
> + ret = mt6360_isnk_init_default_state(led);
> + if (ret) {
> + dev_err(parent, "Failed to init %d isnk state\n", led->led_no);
> + return ret;
> + }
> +
> + ret = devm_led_classdev_register_ext(parent, &led->isnk, init_data);
> + if (ret) {
> + dev_err(parent, "Couldn't register isink %d\n", led->led_no);
> + return ret;
> + }

You probably want also to register V4L2 indicator sub-device.
See drivers/leds/leds-as3645a.c and look for the
v4l2_flash_indicator_init() for reference.

> + return 0;
> +}
> +
> +static int mt6360_flash_init_default_state(struct mt6360_led *led)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> + u32 level;
> + unsigned int regval;
> + int ret;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_FLEDITOR(led->led_no), &regval);
> + if (ret)
> + return ret;
> + level = regval & MT6360_ITORCH_MASK;
> +
> + ret = regmap_read(priv->regmap, MT6360_REG_FLEDEN, &regval);
> + if (ret)
> + return ret;
> +
> + if ((regval & enable_mask) == enable_mask)
> + level += 1;
> + else
> + level = LED_OFF;
> +
> + switch (led->default_state) {
> + case STATE_ON:
> + flash->led_cdev.brightness = flash->led_cdev.max_brightness;
> + break;
> + case STATE_KEEP:
> + flash->led_cdev.brightness = min(level, flash->led_cdev.max_brightness);
> + break;
> + default:
> + flash->led_cdev.brightness = LED_OFF;
> + }
> +
> + return mt6360_torch_brightness_set(&flash->led_cdev, flash->led_cdev.brightness);
> +}
> +
> +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
> +static int mt6360_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
> +{
> + struct led_classdev_flash *flash = v4l2_flash->fled_cdev;
> + struct mt6360_led *led = container_of(flash, struct mt6360_led, flash);
> + struct mt6360_priv *priv = led->priv;
> + u32 enable_mask = MT6360_FLCSEN_MASK(led->led_no);
> + int ret;
> +
> + ret = regmap_update_bits(priv->regmap, MT6360_REG_FLEDEN, enable_mask,
> + enable ? enable_mask : 0);
> + if (ret)
> + return ret;
> +
> + if (enable)
> + priv->fled_strobe_used |= BIT(led->led_no);
> + else
> + priv->fled_strobe_used &= (~BIT(led->led_no));
> +
> + return 0;
> +}
> +
> +static const struct v4l2_flash_ops v4l2_flash_ops = {
> + .external_strobe_set = mt6360_flash_external_strobe_set,
> +};
> +
> +static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct led_classdev *lcdev = &flash->led_cdev;
> + struct led_flash_setting *s = &config->intensity;
> +
> + snprintf(config->dev_name, sizeof(config->dev_name), "%s", lcdev->name);
> +
> + s->min = MT6360_ITORCH_MIN;
> + s->step = MT6360_ITORCH_STEP;
> + s->val = s->max = (s->min) + (lcdev->max_brightness - 1) * s->step;
> +
> + config->has_external_strobe = 1;
> +}
> +#else
> +static const struct v4l2_flash_ops v4l2_flash_ops;
> +
> +static void mt6360_flash_init_v4l2_config(struct mt6360_led *led, struct v4l2_flash_config *config)
> +{
> +}
> +#endif
> +
> +static int mt6360_flash_register(struct device *parent, struct mt6360_led *led,
> + struct led_init_data *init_data)
> +{
> + struct v4l2_flash_config v4l2_config = {0};
> + int ret;
> +
> + ret = mt6360_flash_init_default_state(led);
> + if (ret) {
> + dev_err(parent, "Failed to init %d flash state\n", led->led_no);
> + return ret;
> + }
> +
> + ret = devm_led_classdev_flash_register_ext(parent, &led->flash, init_data);
> + if (ret) {
> + dev_err(parent, "Couldn't register flash %d\n", led->led_no);
> + return ret;
> + }
> +
> + mt6360_flash_init_v4l2_config(led, &v4l2_config);
> + led->v4l2_flash = v4l2_flash_init(parent, init_data->fwnode, &led->flash, &v4l2_flash_ops,
> + &v4l2_config);
> + if (IS_ERR(led->v4l2_flash)) {
> + dev_err(parent, "Failed to register %d v4l2 sd\n", led->led_no);
> + return PTR_ERR(led->v4l2_flash);
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_init_isnk_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + struct led_classdev *isnk = &led->isnk;
> +
> + if (led->led_no == MT6360_LED_ISNK4)
> + isnk->max_brightness = MT6360_ISNK4_MAXLEVEL;
> + else
> + isnk->max_brightness = MT6360_ISNK1_MAXLEVEL;
> +
> + isnk->brightness_set_blocking = mt6360_isnk_brightness_set;
> +
> + fwnode_property_read_string(init_data->fwnode, "linux,default-trigger",
> + &isnk->default_trigger);
> +
> + return 0;
> +}
> +
> +static void clamp_align(u32 *v, u32 min, u32 max, u32 step)
> +{
> + *v = clamp_val(*v, min, max);
> + if (step > 1)
> + *v = (*v - min) / step * step + min;
> +}
> +
> +static int mt6360_init_flash_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + struct led_classdev_flash *flash = &led->flash;
> + struct led_classdev *lcdev = &flash->led_cdev;
> + struct led_flash_setting *s;
> + u32 val;
> + int ret;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "led-max-microamp", &val);
> + if (ret)
> + val = MT6360_ITORCH_MIN;

In case of missing property I would print warning and inform the user
that we're defaulting to min value. Same applies to similar occurrences
below.

> + else
> + clamp_align(&val, MT6360_ITORCH_MIN, MT6360_ITORCH_MAX, MT6360_ITORCH_STEP);
> +
> + lcdev->max_brightness = (val - MT6360_ITORCH_MIN) / MT6360_ITORCH_STEP + 1;
> + lcdev->brightness_set_blocking = mt6360_torch_brightness_set;
> + lcdev->flags |= LED_DEV_CAP_FLASH;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-microamp", &val);
> + if (ret)
> + val = MT6360_ISTRB_MIN;
> + else
> + clamp_align(&val, MT6360_ISTRB_MIN, MT6360_ISTRB_MAX, MT6360_ISTRB_STEP);
> +
> + s = &flash->brightness;
> + s->min = MT6360_ISTRB_MIN;
> + s->step = MT6360_ISTRB_STEP;
> + s->val = s->max = val;
> +
> + /* always configure as min level when off to prevent flash current spike */
> + ret = _mt6360_strobe_brightness_set(flash, s->min);
> + if (ret)
> + return ret;
> +
> + ret = fwnode_property_read_u32(init_data->fwnode, "flash-max-timeout-us", &val);
> + if (ret)
> + val = MT6360_STRBTO_MIN;
> + else
> + clamp_align(&val, MT6360_STRBTO_MIN, MT6360_STRBTO_MAX, MT6360_STRBTO_STEP);
> +
> + s = &flash->timeout;
> + s->min = MT6360_STRBTO_MIN;
> + s->step = MT6360_STRBTO_STEP;
> + s->val = s->max = val;
> +
> + flash->ops = &mt6360_flash_ops;
> +
> + return 0;
> +}
> +
> +static int mt6360_init_common_properties(struct mt6360_led *led, struct led_init_data *init_data)
> +{
> + const char *str;
> +
> + if (!fwnode_property_read_string(init_data->fwnode, "default-state", &str)) {
> + if (!strcmp(str, "on"))
> + led->default_state = STATE_ON;
> + else if (!strcmp(str, "keep"))
> + led->default_state = STATE_KEEP;
> + else
> + led->default_state = STATE_OFF;
> + }
> +
> + return 0;
> +}
> +
> +static int mt6360_led_probe(struct platform_device *pdev)
> +{
> + struct mt6360_priv *priv;
> + struct fwnode_handle *child;
> + int i, ret;
> +
> + ret = device_get_child_node_count(&pdev->dev);
> + if (!ret || ret > MT6360_MAX_LEDS)
> + return -EINVAL;
> +
> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->dev = &pdev->dev;
> +
> + priv->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!priv->regmap) {
> + dev_err(&pdev->dev, "Failed to get parent regmap\n");
> + return -ENODEV;
> + }
> +
> + device_for_each_child_node(&pdev->dev, child) {
> + struct mt6360_led *led;
> + struct led_init_data init_data = { .fwnode = child, };
> + u32 reg;
> +
> + ret = fwnode_property_read_u32(child, "reg", &reg);
> + if (ret || reg >= MT6360_MAX_LEDS || priv->leds[reg]) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
> + if (!led) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + led->led_no = reg;
> + led->priv = priv;
> +
> + ret = mt6360_init_common_properties(led, &init_data);
> + if (ret)
> + goto out;
> +
> + switch (reg) {
> + case MT6360_LED_ISNK1 ... MT6360_LED_ISNK4:
> + ret = mt6360_init_isnk_properties(led, &init_data);
> + if (ret)
> + goto out;
> +
> + ret = mt6360_isnk_register(&pdev->dev, led, &init_data);
> + break;
> + default:
> + ret = mt6360_init_flash_properties(led, &init_data);
> + if (ret)
> + goto out;
> +
> + ret = mt6360_flash_register(&pdev->dev, led, &init_data);
> + }
> +
> + if (ret)
> + goto out;
> +
> + priv->leds[reg] = led;
> + }
> +
> + platform_set_drvdata(pdev, priv);
> + return 0;
> +out:
> + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> + struct mt6360_led *led = priv->leds[i];
> +
> + if (led && led->v4l2_flash)
> + v4l2_flash_release(led->v4l2_flash);
> +
> + }
> +
> + return ret;
> +}
> +
> +static int mt6360_led_remove(struct platform_device *pdev)
> +{
> + struct mt6360_priv *priv = platform_get_drvdata(pdev);
> + int i;
> +
> + for (i = MT6360_LED_FLASH1; i <= MT6360_LED_FLASH2; i++) {
> + struct mt6360_led *led = priv->leds[i];
> +
> + if (led && led->v4l2_flash)
> + v4l2_flash_release(led->v4l2_flash);
> +
> + }

You're using this for loop twice, so it would be nice to wrap
it with a function to avoid code redundancy.

> +
> + return 0;
> +}
> +
> +static const struct of_device_id __maybe_unused mt6360_led_of_id[] = {
> + { .compatible = "mediatek,mt6360-led", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, mt6360_led_of_id);
> +
> +static struct platform_driver mt6360_led_driver = {
> + .driver = {
> + .name = "mt6360-led",
> + .of_match_table = mt6360_led_of_id,
> + },
> + .probe = mt6360_led_probe,
> + .remove = mt6360_led_remove,
> +};
> +module_platform_driver(mt6360_led_driver);
> +
> +MODULE_AUTHOR("Gene Chen <[email protected]>");
> +MODULE_DESCRIPTION("MT6360 Led Driver");
> +MODULE_LICENSE("GPL v2");
>

--
Best regards,
Jacek Anaszewski

2020-09-11 07:07:20

by Pavel Machek

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi!

> >+{
> >+ struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> >+ struct mt6360_priv *priv = led->priv;
> >+ u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> >+ u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> >+ u32 prev = priv->fled_torch_used, curr;
> >+ int ret;
> >+
> >+ dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> >+ if (priv->fled_strobe_used) {
> >+ dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
>
> Doesn't hardware handle that? IOW, what happens when you have enabled
> both torch and flash? If flash just overrides torch mode, than you
> should not prevent enabling torch in this case.

Yep, this is strange/confusing... and was reason why I asked for not
supporting strobe from sysfs.

Could I get you to remove code you are not commenting at when
reviewing?

> >+MODULE_AUTHOR("Gene Chen <[email protected]>");
> >+MODULE_DESCRIPTION("MT6360 Led Driver");

Led -> LED.

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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2020-09-11 07:25:46

by Gene Chen

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Pavel Machek <[email protected]> 於 2020年9月11日 週五 下午3:05寫道:
>
> Hi!
>
> > >+{
> > >+ struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
> > >+ struct mt6360_priv *priv = led->priv;
> > >+ u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
> > >+ u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
> > >+ u32 prev = priv->fled_torch_used, curr;
> > >+ int ret;
> > >+
> > >+ dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
> > >+ if (priv->fled_strobe_used) {
> > >+ dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
> >
> > Doesn't hardware handle that? IOW, what happens when you have enabled
> > both torch and flash? If flash just overrides torch mode, than you
> > should not prevent enabling torch in this case.
>
> Yep, this is strange/confusing... and was reason why I asked for not
> supporting strobe from sysfs.
>
> Could I get you to remove code you are not commenting at when
> reviewing?
>

MT6360 FLED register define is STROBE_EN/TORCH_EN/CS1/CS2 (current
source) 4 bits.
The STROBE_EN/TORCH_EN is shared by FLED1 and FLED2.
If I want to enable FLED1 torch mode, I set TORCH_EN and CS1
If I want to enable FLED2 strobe mode, I set STROBE_EN and CS2
For example I set FLED1 torch, then I set FLED2 strobe.
When I set FLED2 strobe, I will see the strobe current is FLED2 add
FLED1 current which is not I want.
So I need disable FLED1 torch first.
Considering every circumstances is complicated when share same H/W
logic control.
And the other problem is torch mode switch to strobe mode needs ramp
time because strobe and torch mode can't be co-exist.

> > >+MODULE_AUTHOR("Gene Chen <[email protected]>");
> > >+MODULE_DESCRIPTION("MT6360 Led Driver");
>
> Led -> LED.
>

ACK

> Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2020-09-11 20:59:28

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Hi Pavel,

On 9/11/20 9:05 AM, Pavel Machek wrote:
> Hi!
>
>>> +{
>>> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
>>> + struct mt6360_priv *priv = led->priv;
>>> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
>>> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
>>> + u32 prev = priv->fled_torch_used, curr;
>>> + int ret;
>>> +
>>> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
>>> + if (priv->fled_strobe_used) {
>>> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
>>
>> Doesn't hardware handle that? IOW, what happens when you have enabled
>> both torch and flash? If flash just overrides torch mode, than you
>> should not prevent enabling torch in this case.
>
> Yep, this is strange/confusing... and was reason why I asked for not
> supporting strobe from sysfs.

What you say now is even more confusing when we look at your ack
under this patch:

commit 7aea8389a77abf9fde254aca2434a605c7704f58
Author: Jacek Anaszewski <[email protected]>
Date: Fri Jan 9 07:22:51 2015 -0800

leds: Add LED Flash class extension to the LED subsystem

Some LED devices support two operation modes - torch and flash.
This patch provides support for flash LED devices in the LED subsystem
by introducing new sysfs attributes and kernel internal interface.
The attributes being introduced are: flash_brightness, flash_strobe,
flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault,
flash_sync_strobe and available_sync_leds. All the flash related
features are placed in a separate module.

The modifications aim to be compatible with V4L2 framework requirements
related to the flash devices management. The design assumes that V4L2
sub-device can take of the LED class device control and communicate
with it through the kernel internal interface. When V4L2 Flash
sub-device
file is opened, the LED class device sysfs interface is made
unavailable.

Signed-off-by: Jacek Anaszewski <[email protected]>
Acked-by: Kyungmin Park <[email protected]>
Cc: Richard Purdie <[email protected]>
Acked-by: Pavel Machek <[email protected]>
Signed-off-by: Bryan Wu <[email protected]>


> Could I get you to remove code you are not commenting at when
> reviewing?
>
>>> +MODULE_AUTHOR("Gene Chen <[email protected]>");
>>> +MODULE_DESCRIPTION("MT6360 Led Driver");
>
> Led -> LED.
>
> Pavel
>

--
Best regards,
Jacek Anaszewski

2020-09-11 21:26:11

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

On 9/11/20 1:24 AM, Gene Chen wrote:
> Pavel Machek <[email protected]> 於 2020年9月11日 週五 下午3:05寫道:
>>
>> Hi!
>>
>>>> +{
>>>> + struct mt6360_led *led = container_of(lcdev, struct mt6360_led, flash.led_cdev);
>>>> + struct mt6360_priv *priv = led->priv;
>>>> + u32 enable_mask = MT6360_TORCHEN_MASK | MT6360_FLCSEN_MASK(led->led_no);
>>>> + u32 val = (level) ? MT6360_FLCSEN_MASK(led->led_no) : 0;
>>>> + u32 prev = priv->fled_torch_used, curr;
>>>> + int ret;
>>>> +
>>>> + dev_dbg(lcdev->dev, "[%d] brightness %d\n", led->led_no, level);
>>>> + if (priv->fled_strobe_used) {
>>>> + dev_warn(lcdev->dev, "Please disable strobe first [%d]\n", priv->fled_strobe_used);
>>>
>>> Doesn't hardware handle that? IOW, what happens when you have enabled
>>> both torch and flash? If flash just overrides torch mode, than you
>>> should not prevent enabling torch in this case.
>>
>> Yep, this is strange/confusing... and was reason why I asked for not
>> supporting strobe from sysfs.
>>
>> Could I get you to remove code you are not commenting at when
>> reviewing?
>>
>
> MT6360 FLED register define is STROBE_EN/TORCH_EN/CS1/CS2 (current
> source) 4 bits.
> The STROBE_EN/TORCH_EN is shared by FLED1 and FLED2.
> If I want to enable FLED1 torch mode, I set TORCH_EN and CS1
> If I want to enable FLED2 strobe mode, I set STROBE_EN and CS2
> For example I set FLED1 torch, then I set FLED2 strobe.
> When I set FLED2 strobe, I will see the strobe current is FLED2 add
> FLED1 current which is not I want.
> So I need disable FLED1 torch first.
> Considering every circumstances is complicated when share same H/W
> logic control.
> And the other problem is torch mode switch to strobe mode needs ramp
> time because strobe and torch mode can't be co-exist.

Thank you for the explanation. So we have to keep your guards
but I would return -EBUSY instead of -EINVAL.

This would be also consistent with what
drivers/media/v4l2-core/v4l2-flash-led-class.c
does in its v4l2_flash_s_ctrl(), case V4L2_CID_FLASH_STROBE - it returns
-EBUSY if __software_strobe_mode_inactive() returns false.

The advantage of V4L2 Flash interface is that it has LED_MODE that
can be set to torch or flash, but in LED subsystem we don't have
the counterpart.

--
Best regards,
Jacek Anaszewski