dt-bindings: power: supply: Add MediaTek MT6370 Charger

From: ChiYuan Huang <[email protected]>

Add MT6370 backlight binding documentation.

Reviewed-by Rob Herring <[email protected]>

Reviewed-by Daniel Thompson <[email protected]>

Signed-off-by ChiYuan Huang <[email protected]>

Signed-off-by ChiaEn Wu <[email protected]>

---
 .../leds/backlight/mediatek,mt6370-backlight.yaml  | 121 +++++++++++++++++++++
 1 file changed, 121 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/backlight/mediatek,mt6370-backlight.yaml

From: ChiaEn Wu <[email protected]>

Add linear_range_idx macro for declaring the linear_range struct simply.

Signed-off-by ChiaEn Wu <[email protected]>

---

v9
- Revise LINEAR_RANGE() and LINEAR_RANGE_IDX()

---
  include/linux/linear_range.h | 11 +++++++++++
  1 file changed, 11 insertions(+)

include/linux/linear_range.h +11 -0

index fd3d0b3..2e4f4c3 100644
@@ -26,6 +26,17 @@ struct linear_range {
  	unsigned int step;
  };
 
+#define LINEAR_RANGE(_min, _min_sel, _max_sel, _step)		\
+	{							\
+		.min = _min,					\
+		.min_sel = _min_sel,				\
+		.max_sel = _max_sel,				\
+		.step = _step,					\
+	}
+
+#define LINEAR_RANGE_IDX(_idx, _min, _min_sel, _max_sel, _step)	\
+	[_idx] = LINEAR_RANGE(_min, _min_sel, _max_sel, _step)
+
  unsigned int linear_range_values_in_range(const struct linear_range *r);
  unsigned int linear_range_values_in_range_array(const struct linear_range *r,
  						int ranges);

From: ChiaEn Wu <[email protected]>

MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight driver, display bias voltage supply, one general purpose LDO, and the USB Type-C & PD controller complies with the latest USB Type-C and PD standards.

Add support for the MediaTek MT6370 Charger driver. The charger module of MT6370 supports High-Accuracy Voltage/Current Regulation, Average Input Current Regulation, Battery Temperature Sensing, Over-Temperature Protection, DPDM Detection for BC1.2.

Reviewed-by Andy Shevchenko <[email protected]>

Signed-off-by ChiaEn Wu <[email protected]>

---

From: Alice Chen <[email protected]>

The MediaTek MT6370 is a highly-integrated smart power management IC, which includes a single cell Li-Ion/Li-Polymer switching battery charger, a USB Type-C & Power Delivery (PD) controller, dual Flash LED current sources, a RGB LED driver, a backlight WLED driver, a display bias driver and a general LDO for portable devices.

Add support for the MT6370 Flash LED driver. Flash LED in MT6370 has 2 channels and support torch/strobe mode.

Signed-off-by Alice Chen <[email protected]>

Signed-off-by ChiaEn Wu <[email protected]>

---

v9
- Revise the format of the comments.

---
  drivers/leds/flash/Kconfig             |  14 +
  drivers/leds/flash/Makefile            |   1 +
  drivers/leds/flash/leds-mt6370-flash.c | 632 +++++++++++++++++++++++++++++++++
  3 files changed, 647 insertions(+)

create mode 100644 drivers/leds/flash/leds-mt6370-flash.c

drivers/leds/flash/Kconfig +14 -0

index d3eb689..405bd16 100644
@@ -61,6 +61,20 @@ config LEDS_MT6360
  	  Independent current sources supply for each flash LED support torch
  	  and strobe mode.
 
+config LEDS_MT6370_FLASH
+	tristate "Flash LED Support for MediaTek MT6370 PMIC"
+	depends on LEDS_CLASS && OF
+	depends on LEDS_CLASS_FLASH || !LEDS_CLASS_FLASH
+	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+	depends on MFD_MT6370
+	help
+	  Support 2 channels and torch/strobe mode.
+	  Say Y here to enable support for
+	  MT6370_FLASH_LED device.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called "leds-mt6370-flash".
+
  config LEDS_RT4505
  	tristate "LED support for RT4505 flashlight controller"
  	depends on I2C && OF

drivers/leds/flash/Makefile +1 -0

index 0acbddc..0c1f3c5 100644
@@ -9,3 +9,4 @@ obj-$(CONFIG_LEDS_MAX77693)	+= leds-max77693.o
  obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
  obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
  obj-$(CONFIG_LEDS_SGM3140)	+= leds-sgm3140.o
+obj-$(CONFIG_LEDS_MT6370_FLASH)	+= leds-mt6370-flash.o

drivers/leds/flash/leds-mt6370-flash.c new file +66 -0

new file mode 100644
index 0000000..a8ec7e1
@@ -0,0 +1,632 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Richtek Technology Corp.
+ *
+ * Author: Alice Chen <[email protected]>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/led-class-flash.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#include <media/v4l2-flash-led-class.h>
+
+enum {
+	MT6370_LED_FLASH1,
+	MT6370_LED_FLASH2,
+	MT6370_MAX_LEDS
+};
+
+/* Virtual definition for multicolor */
+
+#define MT6370_REG_FLEDEN		0x17E
+#define MT6370_REG_STRBTO		0x173
+#define MT6370_REG_CHGSTAT2		0x1D1
+#define MT6370_REG_FLEDSTAT1		0x1D9
+#define MT6370_REG_FLEDISTRB(_id)	(0x174 + 4 * (_id))
+#define MT6370_REG_FLEDITOR(_id)	(0x175 + 4 * (_id))
+#define MT6370_ITORCH_MASK		GENMASK(4, 0)
+#define MT6370_ISTROBE_MASK		GENMASK(6, 0)
+#define MT6370_STRBTO_MASK		GENMASK(6, 0)
+#define MT6370_TORCHEN_MASK		BIT(3)
+#define MT6370_STROBEN_MASK		BIT(2)
+#define MT6370_FLCSEN_MASK(_id)		BIT(MT6370_LED_FLASH2 - (_id))
+#define MT6370_FLCSEN_MASK_ALL		GENMASK(1, 0)
+#define MT6370_FLEDCHGVINOVP_MASK	BIT(3)
+#define MT6370_FLED1STRBTO_MASK		BIT(11)
+#define MT6370_FLED2STRBTO_MASK		BIT(10)
+#define MT6370_FLED1STRB_MASK		BIT(9)
+#define MT6370_FLED2STRB_MASK		BIT(8)
+#define MT6370_FLED1SHORT_MASK		BIT(7)
+#define MT6370_FLED2SHORT_MASK		BIT(6)
+#define MT6370_FLEDLVF_MASK		BIT(3)
+
+#define MT6370_LED_JOINT		2
+#define MT6370_RANGE_FLED_REG		4
+#define MT6370_ITORCH_MIN_uA		25000
+#define MT6370_ITORCH_STEP_uA		12500
+#define MT6370_ITORCH_MAX_uA		400000
+#define MT6370_ITORCH_DOUBLE_MAX_uA	800000
+#define MT6370_ISTRB_MIN_uA		50000
+#define MT6370_ISTRB_STEP_uA		12500
+#define MT6370_ISTRB_MAX_uA		1500000
+#define MT6370_ISTRB_DOUBLE_MAX_uA	3000000
+#define MT6370_STRBTO_MIN_US		64000
+#define MT6370_STRBTO_STEP_US		32000
+#define MT6370_STRBTO_MAX_US		2432000
+
+#define STATE_OFF			0

drivers/leds/flash/leds-mt6370-flash.c new file +95 -0

+};
+
+struct mt6370_priv {
+	struct device *dev;
+	struct regmap *regmap;
+	struct mutex lock;
+	unsigned int fled_strobe_used;
+	unsigned int fled_torch_used;
+	unsigned int leds_active;
+	unsigned int leds_count;
+	struct mt6370_led leds[];
+};
+
+static int mt6370_torch_brightness_set(struct led_classdev *lcdev,
+				       enum led_brightness level)
+{
+	struct mt6370_led *led = to_mt6370_led(lcdev, flash.led_cdev);
+	struct mt6370_priv *priv = led->priv;
+	u32 led_enable_mask = (led->led_no == MT6370_LED_JOINT) ?
+			      MT6370_FLCSEN_MASK_ALL :
+			      MT6370_FLCSEN_MASK(led->led_no);
+	u32 enable_mask = MT6370_TORCHEN_MASK | led_enable_mask;
+	u32 val = level ? led_enable_mask : 0;
+	u32 curr;
+	int ret, i;
+
+	mutex_lock(&priv->lock);
+
+	/*
+	 * There is only one set of flash control logic, and this
+	 * flag is used to check if 'strobe' is currently being used.
+	 */
+	if (priv->fled_strobe_used) {
+		dev_warn(lcdev->dev, "Please disable strobe first [%d]\n",
+			 priv->fled_strobe_used);
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (level)
+		curr = priv->fled_torch_used | BIT(led->led_no);
+	else
+		curr = priv->fled_torch_used & ~BIT(led->led_no);
+
+	if (curr)
+		val |= MT6370_TORCHEN_MASK;
+
+	if (level) {
+		level -= 1;
+		if (led->led_no == MT6370_LED_JOINT) {
+			int flevel[MT6370_MAX_LEDS];
+
+			flevel[0] = level / 2;
+			flevel[1] = level - flevel[0];
+			for (i = 0; i < MT6370_MAX_LEDS; i++) {
+				ret = regmap_update_bits(priv->regmap,
+						MT6370_REG_FLEDITOR(i),
+						MT6370_ITORCH_MASK, flevel[i]);
+				if (ret)
+					goto unlock;
+			}
+		} else {
+			ret = regmap_update_bits(priv->regmap,
+					MT6370_REG_FLEDITOR(led->led_no),
+					MT6370_ITORCH_MASK, level);
+			if (ret)
+				goto unlock;
+		}
+	}
+
+	ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN,
+				 enable_mask, val);
+	if (ret)
+		goto unlock;
+
+	priv->fled_torch_used = curr;
+
+unlock:
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+
+static int mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev,
+				       u32 brightness)
+{
+	/*
+	 * Because of the current spikes when turning on the flash,
+	 * the brightness should be kept by the LED framework. This
+	 * empty function is used to prevent checking failure when
+	 * led_classdev_flash registers ops.
+	 */
+	return 0;
+}
+
+static int _mt6370_flash_brightness_set(struct led_classdev_flash *fl_cdev,

drivers/leds/flash/leds-mt6370-flash.c new file +7 -0

+
+		flevel[0] = val / 2;
+		flevel[1] = val - flevel[0];
+		for (i = 0; i < MT6370_MAX_LEDS; i++) {
+			ret = regmap_update_bits(priv->regmap,
+						 MT6370_REG_FLEDISTRB(i),
+						 MT6370_ISTROBE_MASK, flevel[i]);

drivers/leds/flash/leds-mt6370-flash.c new file +43 -0

+}
+
+static int mt6370_strobe_set(struct led_classdev_flash *fl_cdev, bool state)
+{
+	struct mt6370_led *led = to_mt6370_led(fl_cdev, flash);
+	struct mt6370_priv *priv = led->priv;
+	struct led_classdev *lcdev = &fl_cdev->led_cdev;
+	struct led_flash_setting *s = &fl_cdev->brightness;
+	u32 led_enable_mask = (led->led_no == MT6370_LED_JOINT) ?
+			      MT6370_FLCSEN_MASK_ALL :
+			      MT6370_FLCSEN_MASK(led->led_no);
+	u32 enable_mask = MT6370_STROBEN_MASK | led_enable_mask;
+	u32 val = state ? led_enable_mask : 0;
+	u32 curr;
+	int ret;
+
+	mutex_lock(&priv->lock);
+
+	/*
+	 * There is only one set of flash control logic, and this
+	 * flag is used to check if 'torch' is currently being used.
+	 */
+	if (priv->fled_torch_used) {
+		dev_warn(lcdev->dev, "Please disable torch first [0x%x]\n",
+				      priv->fled_torch_used);
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (state)
+		curr = priv->fled_strobe_used | BIT(led->led_no);
+	else
+		curr = priv->fled_strobe_used & ~BIT(led->led_no);
+
+	if (curr)
+		val |= MT6370_STROBEN_MASK;
+
+	ret = regmap_update_bits(priv->regmap, MT6370_REG_FLEDEN, enable_mask,
+				 val);
+	if (ret) {
+		dev_err(lcdev->dev, "[%d] control current source %d fail\n",
+				     led->led_no, state);
+		goto unlock;

drivers/leds/flash/leds-mt6370-flash.c new file +17 -0

+
+	/*
+	 * For the flash to turn on/off, we must wait for HW ramping
+	 * up/down time 5ms/500us to prevent the unexpected problem.
+	 */
+	if (!priv->fled_strobe_used && curr)
+		usleep_range(5000, 6000);
+	else if (priv->fled_strobe_used && !curr)
+		usleep_range(500, 600);
+
+	priv->fled_strobe_used = curr;
+
+unlock:
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+

drivers/leds/flash/leds-mt6370-flash.c new file +37 -0

+
+static int mt6370_init_common_properties(struct mt6370_led *led,
+					 struct led_init_data *init_data)
+{
+	const char * const states[] = { "off", "keep", "on" };
+	const char *str = states[STATE_OFF];
+	int ret;
+
+	fwnode_property_read_string(init_data->fwnode, "default-state", &str);
+	ret = match_string(states, ARRAY_SIZE(states), str);
+	if (ret >= 0)
+		led->default_state = ret;
+
+	return 0;
+}
+
+static int mt6370_led_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mt6370_priv *priv;
+	struct fwnode_handle *child;
+	size_t count;
+	int i = 0, ret;
+
+	count = device_get_child_node_count(dev);
+	if (!count || count > MT6370_MAX_LEDS)
+		return dev_err_probe(dev, -EINVAL,
+		       "No child node or node count over max led number %zu\n", count);
+
+	priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->leds_count = count;
+	priv->dev = dev;
+	mutex_init(&priv->lock);
+

drivers/leds/flash/leds-mt6370-flash.c new file +7 -0

+		if (ret)
+			return ret;
+
+		ret = mt6370_init_flash_properties(led, &init_data);
+		if (ret)
+			return ret;
+

On Mon, Aug 29, 2022 ChiaEn Wu <[email protected]> wrote:

drivers/leds/flash/leds-mt6370-flash.c line 61

Quoted 8 lines

drivers/leds/flash/leds-mt6370-flash.c new file +8 -0

+#define MT6370_ITORCH_MIN_uA           25000
+#define MT6370_ITORCH_STEP_uA          12500
+#define MT6370_ITORCH_MAX_uA           400000
+#define MT6370_ITORCH_DOUBLE_MAX_uA    800000
+#define MT6370_ISTRB_MIN_uA            50000
+#define MT6370_ISTRB_STEP_uA           12500
+#define MT6370_ISTRB_MAX_uA            1500000
+#define MT6370_ISTRB_DOUBLE_MAX_uA     3000000

Use upper letters as below:

#define MT6370_ITORCH_MIN_UA           25000
#define MT6370_ITORCH_STEP_UA          12500
#define MT6370_ITORCH_MAX_UA           400000
#define MT6370_ITORCH_DOUBLE_MAX_UA    800000
#define MT6370_ISTRB_MIN_UA            50000
#define MT6370_ISTRB_STEP_UA           12500
#define MT6370_ISTRB_MAX_UA            1500000
#define MT6370_ISTRB_DOUBLE_MAX_UA     3000000

drivers/leds/flash/leds-mt6370-flash.c line 65

Quoted 4 lines

drivers/leds/flash/leds-mt6370-flash.c new file +4 -0

+#define MT6370_STRBTO_MIN_US           64000
+#define MT6370_STRBTO_STEP_US          32000
+#define MT6370_STRBTO_MAX_US           2432000
+

Quoted 12 lines · Han Jingoo

drivers/leds/flash/leds-mt6370-flash.c line 61

Quoted 8 lines · On Mon, Aug 29, 2022 ChiaEn Wu <[email protected]> wrote:

drivers/leds/flash/leds-mt6370-flash.c new file +8 -0

+#define MT6370_ITORCH_MIN_uA           25000
+#define MT6370_ITORCH_STEP_uA          12500
+#define MT6370_ITORCH_MAX_uA           400000
+#define MT6370_ITORCH_DOUBLE_MAX_uA    800000
+#define MT6370_ISTRB_MIN_uA            50000
+#define MT6370_ISTRB_STEP_uA           12500
+#define MT6370_ISTRB_MAX_uA            1500000
+#define MT6370_ISTRB_DOUBLE_MAX_uA     3000000

Use upper letters as below:

Quoted 9 lines

#define MT6370_ITORCH_MIN_UA           25000
#define MT6370_ITORCH_STEP_UA          12500
#define MT6370_ITORCH_MAX_UA           400000
#define MT6370_ITORCH_DOUBLE_MAX_UA    800000
#define MT6370_ISTRB_MIN_UA            50000
#define MT6370_ISTRB_STEP_UA           12500
#define MT6370_ISTRB_MAX_UA            1500000
#define MT6370_ISTRB_DOUBLE_MAX_UA     3000000

Quoted 3 lines

drivers/leds/flash/leds-mt6370-flash.c line 64

Quoted 3 lines

drivers/leds/flash/leds-mt6370-flash.c new file +3 -0

+#define MT6370_STRBTO_MIN_US           64000
+#define MT6370_STRBTO_STEP_US          32000
+#define MT6370_STRBTO_MAX_US           2432000

Hi Jingoo,

This coding style is in accordance with Andy's opinion in this mail:
https://lore.kernel.org/linux-arm-kernel/CAHp75Vciq4M4kVrabNV9vTLLcd1vR=bMe8JLEdAF9MkRTpcB5g@mail.gmail.com/

Quoted 13 lines · ChiaEn Wu

Quoted 12 lines · Han Jingoo

drivers/leds/flash/leds-mt6370-flash.c line 61

Quoted 8 lines · On Mon, Aug 29, 2022 ChiaEn Wu <[email protected]> wrote:

drivers/leds/flash/leds-mt6370-flash.c new file +8 -0

+#define MT6370_ITORCH_MIN_uA           25000
+#define MT6370_ITORCH_STEP_uA          12500
+#define MT6370_ITORCH_MAX_uA           400000
+#define MT6370_ITORCH_DOUBLE_MAX_uA    800000
+#define MT6370_ISTRB_MIN_uA            50000
+#define MT6370_ISTRB_STEP_uA           12500
+#define MT6370_ISTRB_MAX_uA            1500000
+#define MT6370_ISTRB_DOUBLE_MAX_uA     3000000

Use upper letters as below:

For microseconds (and other -seconds) the common practice (I assume historically) is to use upper letters, indeed. But for current it's more natural to use small letters for unit multiplier as it's easier to read and understand.

Quoted 10 lines

Quoted 10 lines

#define MT6370_ITORCH_MIN_UA           25000
#define MT6370_ITORCH_STEP_UA          12500
#define MT6370_ITORCH_MAX_UA           400000
#define MT6370_ITORCH_DOUBLE_MAX_UA    800000
#define MT6370_ISTRB_MIN_UA            50000
#define MT6370_ISTRB_STEP_UA           12500
#define MT6370_ISTRB_MAX_UA            1500000
#define MT6370_ISTRB_DOUBLE_MAX_UA     3000000

Quoted 8 lines

Quoted 3 lines

drivers/leds/flash/leds-mt6370-flash.c line 64

Quoted 3 lines

drivers/leds/flash/leds-mt6370-flash.c new file +3 -0

+#define MT6370_STRBTO_MIN_US           64000
+#define MT6370_STRBTO_STEP_US          32000
+#define MT6370_STRBTO_MAX_US           2432000

Hi Jingoo,

This coding style is in accordance with Andy's opinion in this mail:
https://lore.kernel.org/linux-arm-kernel/CAHp75Vciq4M4kVrabNV9vTLLcd1vR=bMe8JLEdAF9MkRTpcB5g@mail.gmail.com/

True.

--
With Best Regards,
Andy Shevchenko

Quoted 16 lines · On Wed, Sep 21, 2022 Andy Shevchenko <[email protected]> wrote:

Quoted 13 lines · ChiaEn Wu

Quoted 12 lines · Han Jingoo

drivers/leds/flash/leds-mt6370-flash.c line 61

Quoted 8 lines · On Mon, Aug 29, 2022 ChiaEn Wu <[email protected]> wrote:

drivers/leds/flash/leds-mt6370-flash.c new file +8 -0

+#define MT6370_ITORCH_MIN_uA           25000
+#define MT6370_ITORCH_STEP_uA          12500
+#define MT6370_ITORCH_MAX_uA           400000
+#define MT6370_ITORCH_DOUBLE_MAX_uA    800000
+#define MT6370_ISTRB_MIN_uA            50000
+#define MT6370_ISTRB_STEP_uA           12500
+#define MT6370_ISTRB_MAX_uA            1500000
+#define MT6370_ISTRB_DOUBLE_MAX_uA     3000000

Use upper letters as below:

Quoted 4 lines

For microseconds (and other -seconds) the common practice (I assume historically) is to use upper letters, indeed. But for current it's more natural to use small letters for unit multiplier as it's easier to read and understand.

From: ChiaEn Wu <[email protected]>

MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight driver, display bias voltage supply, one general purpose LDO, and the USB Type-C & PD controller complies with the latest USB Type-C and PD standards.

Add support for the MediaTek MT6370 backlight driver. It controls 4 channels of 8 series WLEDs in
2048 (only for MT6370/MT6371) / 16384 (only for MT6372) current steps (30 mA) in exponential or linear mapping curves.

Reviewed-by Daniel Thompson <[email protected]>

Signed-off-by ChiaEn Wu <[email protected]>

---

v9
- Revise the format of the comments.

---
 drivers/video/backlight/Kconfig            |  13 ++
 drivers/video/backlight/Makefile           |   1 +
 drivers/video/backlight/mt6370-backlight.c | 351 +++++++++++++++++++++++++++++
 3 files changed, 365 insertions(+)
 create mode 100644 drivers/video/backlight/mt6370-backlight.c

From: ChiaEn Wu <[email protected]>

MediaTek MT6370 is a SubPMIC consisting of a single cell battery charger with ADC monitoring, RGB LEDs, dual channel flashlight, WLED backlight driver, display bias voltage supply, one general purpose LDO, and the USB Type-C & PD controller complies with the latest USB Type-C and PD standards.

Add support for the MediaTek MT6370 backlight driver. It controls 4 channels of 8 series WLEDs in
2048 (only for MT6370/MT6371) / 16384 (only for MT6372) current steps (30 mA) in exponential or linear mapping curves.

Reviewed-by Daniel Thompson <[email protected]>

Signed-off-by ChiaEn Wu <[email protected]>

---

v9
- Revise the format of the comments.

---
 drivers/video/backlight/Kconfig            |  13 ++
 drivers/video/backlight/Makefile           |   1 +
 drivers/video/backlight/mt6370-backlight.c | 351 +++++++++++++++++++++++++++++
 3 files changed, 365 insertions(+)
 create mode 100644 drivers/video/backlight/mt6370-backlight.c