[PATCH v8 0/2] Add LED driver for flash module in QCOM PMICs

[PATCH v8 0/2] Add LED driver for flash module in QCOM PMICs

[Fenglin Wu]

Initial driver and binding document changes for supporting flash LED
module in Qualcomm Technologies, Inc. PMICs.

Changes in V8:
  1. Introduce a helper function 'flcdev_to_qcom_fled()'.
  2. Rename 'struct qcom_flash_chip' as 'struct qcom_flash_data' and
     remove 'qcom_flash_led' data pointers from it to avoid interwoven
     reference. Also remove the 'dev' pointer.
  3. Remove 'v4l2_flash' data pointer in 'struct qcom_flash_led' and
     move it to 'struct qcom_flash_data'.
	
Changes in V7:
  1. Fix compilation issue reported by kernel test robot

Changes in V6:
  1. Update the driver to address review comments from Jones,Lee.

Changes in V5:
  1. Add MODULE_DEVICE_TABLE for auto-loading.

Changes in V4:
  1. Added Tested-By tag.
  2. Addressed review comments in the binding change and added
     Reviewed-by tag.

Changes in V3:
  1. Updated the driver to use regmap_field for register access.
  2. Adressed the review comments in binding document change.

Changes in V2:
  1. Addressed review comments in binding change, thanks Krzysztof!
  2. Updated driver to address the compilation issue reported by
     kernel test robot.


Fenglin Wu (2):
  leds: flash: add driver to support flash LED module in QCOM PMICs
  dt-bindings: leds: add QCOM flash LED controller

 .../bindings/leds/qcom,spmi-flash-led.yaml    | 116 +++
 drivers/leds/flash/Kconfig                    |  15 +
 drivers/leds/flash/Makefile                   |   1 +
 drivers/leds/flash/leds-qcom-flash.c          | 773 ++++++++++++++++++
 4 files changed, 905 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml
 create mode 100644 drivers/leds/flash/leds-qcom-flash.c

-- 
2.25.1

[PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Fenglin Wu]

Add initial driver to support flash LED module found in Qualcomm
Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
and each channel can be controlled indepedently and support full scale
current up to 1.5 A. It also supports connecting two channels together
to supply one LED component with full scale current up to 2 A. In that
case, the current will be split on each channel symmetrically and the
channels will be enabled and disabled at the same time.

Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sm7225-fairphone-fp4 + pm6150l
---
 drivers/leds/flash/Kconfig           |  15 +
 drivers/leds/flash/Makefile          |   1 +
 drivers/leds/flash/leds-qcom-flash.c | 773 +++++++++++++++++++++++++++
 3 files changed, 789 insertions(+)
 create mode 100644 drivers/leds/flash/leds-qcom-flash.c

diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
index d3eb689b193c..f36a60409290 100644
--- a/drivers/leds/flash/Kconfig
+++ b/drivers/leds/flash/Kconfig
@@ -61,6 +61,21 @@ config LEDS_MT6360
 	  Independent current sources supply for each flash LED support torch
 	  and strobe mode.
 
+config LEDS_QCOM_FLASH
+	tristate "LED support for flash module inside Qualcomm Technologies, Inc. PMIC"
+	depends on MFD_SPMI_PMIC || COMPILE_TEST
+	depends on LEDS_CLASS && OF
+	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+	select REGMAP
+	help
+	  This option enables support for the flash module found in Qualcomm
+	  Technologies, Inc. PMICs. The flash module can have 3 or 4 flash LED
+	  channels and each channel is programmable to support up to 1.5 A full
+	  scale current. It also supports connecting two channels' output together
+	  to supply one LED component to achieve current up to 2 A. In such case,
+	  the total LED current will be split symmetrically on each channel and
+	  they will be enabled/disabled at the same time.
+
 config LEDS_RT4505
 	tristate "LED support for RT4505 flashlight controller"
 	depends on I2C && OF
diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
index 0acbddc0b91b..8a60993f1a25 100644
--- a/drivers/leds/flash/Makefile
+++ b/drivers/leds/flash/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_LEDS_AS3645A)	+= leds-as3645a.o
 obj-$(CONFIG_LEDS_KTD2692)	+= leds-ktd2692.o
 obj-$(CONFIG_LEDS_LM3601X)	+= leds-lm3601x.o
 obj-$(CONFIG_LEDS_MAX77693)	+= leds-max77693.o
+obj-$(CONFIG_LEDS_QCOM_FLASH)	+= leds-qcom-flash.o
 obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
 obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
 obj-$(CONFIG_LEDS_SGM3140)	+= leds-sgm3140.o
diff --git a/drivers/leds/flash/leds-qcom-flash.c b/drivers/leds/flash/leds-qcom-flash.c
new file mode 100644
index 000000000000..406ed8761c78
--- /dev/null
+++ b/drivers/leds/flash/leds-qcom-flash.c
@@ -0,0 +1,773 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/leds.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>
+
+/* registers definitions */
+#define FLASH_TYPE_REG			0x04
+#define FLASH_TYPE_VAL			0x18
+
+#define FLASH_SUBTYPE_REG		0x05
+#define FLASH_SUBTYPE_3CH_VAL		0x04
+#define FLASH_SUBTYPE_4CH_VAL		0x07
+
+#define FLASH_STS_3CH_OTST1		BIT(0)
+#define FLASH_STS_3CH_OTST2		BIT(1)
+#define FLASH_STS_3CH_OTST3		BIT(2)
+#define FLASH_STS_3CH_BOB_THM_OVERLOAD	BIT(3)
+#define FLASH_STS_3CH_VPH_DROOP		BIT(4)
+#define FLASH_STS_3CH_BOB_ILIM_S1	BIT(5)
+#define FLASH_STS_3CH_BOB_ILIM_S2	BIT(6)
+#define FLASH_STS_3CH_BCL_IBAT		BIT(7)
+
+#define FLASH_STS_4CH_VPH_LOW		BIT(0)
+#define FLASH_STS_4CH_BCL_IBAT		BIT(1)
+#define FLASH_STS_4CH_BOB_ILIM_S1	BIT(2)
+#define FLASH_STS_4CH_BOB_ILIM_S2	BIT(3)
+#define FLASH_STS_4CH_OTST2		BIT(4)
+#define FLASH_STS_4CH_OTST1		BIT(5)
+#define FLASH_STS_4CHG_BOB_THM_OVERLOAD	BIT(6)
+
+#define FLASH_TIMER_EN_BIT		BIT(7)
+#define FLASH_TIMER_VAL_MASK		GENMASK(6, 0)
+#define FLASH_TIMER_STEP_MS		10
+
+#define FLASH_STROBE_HW_SW_SEL_BIT	BIT(2)
+#define SW_STROBE_VAL			0
+#define HW_STROBE_VAL			1
+#define FLASH_HW_STROBE_TRIGGER_SEL_BIT	BIT(1)
+#define STROBE_LEVEL_TRIGGER_VAL	0
+#define STROBE_EDGE_TRIGGER_VAL		1
+#define FLASH_STROBE_POLARITY_BIT	BIT(0)
+#define STROBE_ACTIVE_HIGH_VAL		1
+
+#define FLASH_IRES_MASK_4CH		BIT(0)
+#define FLASH_IRES_MASK_3CH		GENMASK(1, 0)
+#define FLASH_IRES_12P5MA_VAL		0
+#define FLASH_IRES_5MA_VAL_4CH		1
+#define FLASH_IRES_5MA_VAL_3CH		3
+
+/* constants */
+#define FLASH_CURRENT_MAX_UA		1500000
+#define TORCH_CURRENT_MAX_UA		500000
+#define FLASH_TOTAL_CURRENT_MAX_UA	2000000
+#define FLASH_CURRENT_DEFAULT_UA	1000000
+#define TORCH_CURRENT_DEFAULT_UA	200000
+
+#define TORCH_IRES_UA			5000
+#define FLASH_IRES_UA			12500
+
+#define FLASH_TIMEOUT_MAX_US		1280000
+#define FLASH_TIMEOUT_STEP_US		10000
+
+#define UA_PER_MA			1000
+
+enum hw_type {
+	QCOM_MVFLASH_3CH,
+	QCOM_MVFLASH_4CH,
+};
+
+enum led_mode {
+	FLASH_MODE,
+	TORCH_MODE,
+};
+
+enum led_strobe {
+	SW_STROBE,
+	HW_STROBE,
+};
+
+enum {
+	REG_STATUS1,
+	REG_STATUS2,
+	REG_STATUS3,
+	REG_CHAN_TIMER,
+	REG_ITARGET,
+	REG_MODULE_EN,
+	REG_IRESOLUTION,
+	REG_CHAN_STROBE,
+	REG_CHAN_EN,
+	REG_MAX_COUNT,
+};
+
+struct reg_field mvflash_3ch_regs[REG_MAX_COUNT] = {
+	REG_FIELD(0x08, 0, 7),			/* status1	*/
+	REG_FIELD(0x09, 0, 7),                  /* status2	*/
+	REG_FIELD(0x0a, 0, 7),                  /* status3	*/
+	REG_FIELD_ID(0x40, 0, 7, 3, 1),         /* chan_timer	*/
+	REG_FIELD_ID(0x43, 0, 6, 3, 1),         /* itarget	*/
+	REG_FIELD(0x46, 7, 7),                  /* module_en	*/
+	REG_FIELD(0x47, 0, 5),                  /* iresolution	*/
+	REG_FIELD_ID(0x49, 0, 2, 3, 1),         /* chan_strobe	*/
+	REG_FIELD(0x4c, 0, 2),                  /* chan_en	*/
+};
+
+struct reg_field mvflash_4ch_regs[REG_MAX_COUNT] = {
+	REG_FIELD(0x06, 0, 7),			/* status1	*/
+	REG_FIELD(0x07, 0, 6),			/* status2	*/
+	REG_FIELD(0x09, 0, 7),			/* status3	*/
+	REG_FIELD_ID(0x3e, 0, 7, 4, 1),		/* chan_timer	*/
+	REG_FIELD_ID(0x42, 0, 6, 4, 1),		/* itarget	*/
+	REG_FIELD(0x46, 7, 7),			/* module_en	*/
+	REG_FIELD(0x49, 0, 3),			/* iresolution	*/
+	REG_FIELD_ID(0x4a, 0, 6, 4, 1),		/* chan_strobe	*/
+	REG_FIELD(0x4e, 0, 3),			/* chan_en	*/
+};
+
+struct qcom_flash_data {
+	struct v4l2_flash	**v4l2_flash;
+	struct regmap_field     *r_fields[REG_MAX_COUNT];
+	struct mutex		lock;
+	enum hw_type		hw_type;
+	u8			leds_count;
+	u8			max_channels;
+	u8			chan_en_bits;
+};
+
+struct qcom_flash_led {
+	struct qcom_flash_data		*flash_data;
+	struct led_classdev_flash	flash;
+	u32				max_flash_current_ma;
+	u32				max_torch_current_ma;
+	u32				max_timeout_ms;
+	u32				flash_current_ma;
+	u32				flash_timeout_ms;
+	u8				*chan_id;
+	u8				chan_count;
+	bool				enabled;
+};
+
+static int set_flash_module_en(struct qcom_flash_led *led, bool en)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	u8 led_mask = 0, enable;
+	int i, rc;
+
+	for (i = 0; i < led->chan_count; i++)
+		led_mask |= BIT(led->chan_id[i]);
+
+	mutex_lock(&flash_data->lock);
+	if (en)
+		flash_data->chan_en_bits |= led_mask;
+	else
+		flash_data->chan_en_bits &= ~led_mask;
+
+	enable = !!flash_data->chan_en_bits;
+	rc = regmap_field_write(flash_data->r_fields[REG_MODULE_EN], enable);
+	if (rc)
+		dev_err(led->flash.led_cdev.dev, "write module_en failed, rc=%d\n", rc);
+	mutex_unlock(&flash_data->lock);
+
+	return rc;
+}
+
+static int set_flash_current(struct qcom_flash_led *led, u32 current_ma, enum led_mode mode)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	u32 itarg_ua, ires_ua;
+	u8 shift, ires_mask = 0, ires_val = 0, chan_id;
+	int i, rc;
+
+	/*
+	 * Split the current across the channels and set the
+	 * IRESOLUTION and ITARGET registers accordingly.
+	 */
+	itarg_ua = (current_ma * UA_PER_MA) / led->chan_count + 1;
+	ires_ua = (mode == FLASH_MODE) ? FLASH_IRES_UA : TORCH_IRES_UA;
+
+	for (i = 0; i < led->chan_count; i++) {
+		u8 itarget = 0;
+
+		if (itarg_ua > ires_ua)
+			itarget = itarg_ua / ires_ua - 1;
+
+		chan_id = led->chan_id[i];
+
+		rc = regmap_fields_write(flash_data->r_fields[REG_ITARGET], chan_id, itarget);
+		if (rc)
+			return rc;
+
+		if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
+			shift = chan_id * 2;
+			ires_mask |= FLASH_IRES_MASK_3CH << shift;
+			ires_val |= ((mode == FLASH_MODE) ?
+				(FLASH_IRES_12P5MA_VAL << shift) :
+				(FLASH_IRES_5MA_VAL_3CH << shift));
+		} else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
+			shift = chan_id;
+			ires_mask |= FLASH_IRES_MASK_4CH << shift;
+			ires_val |= ((mode == FLASH_MODE) ?
+				(FLASH_IRES_12P5MA_VAL << shift) :
+				(FLASH_IRES_5MA_VAL_4CH << shift));
+		} else {
+			dev_err(led->flash.led_cdev.dev,
+					"HW type %d is not supported\n", flash_data->hw_type);
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return regmap_field_update_bits(flash_data->r_fields[REG_IRESOLUTION], ires_mask, ires_val);
+}
+
+static int set_flash_timeout(struct qcom_flash_led *led, u32 timeout_ms)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	u8 timer, chan_id;
+	int rc, i;
+
+	/* set SAFETY_TIMER for all the channels connected to the same LED */
+	timeout_ms = min_t(u32, timeout_ms, led->max_timeout_ms);
+
+	for (i = 0; i < led->chan_count; i++) {
+		chan_id = led->chan_id[i];
+
+		timer = timeout_ms / FLASH_TIMER_STEP_MS;
+		timer = clamp_t(u8, timer, 0, FLASH_TIMER_VAL_MASK);
+
+		if (timeout_ms)
+			timer |= FLASH_TIMER_EN_BIT;
+
+		rc = regmap_fields_write(flash_data->r_fields[REG_CHAN_TIMER], chan_id, timer);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int set_flash_strobe(struct qcom_flash_led *led, enum led_strobe strobe, bool state)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	u8 strobe_sel, chan_en, chan_id, chan_mask = 0;
+	int rc, i;
+
+	/* Set SW strobe config for all channels connected to the LED */
+	for (i = 0; i < led->chan_count; i++) {
+		chan_id = led->chan_id[i];
+
+		if (strobe == SW_STROBE)
+			strobe_sel = FIELD_PREP(FLASH_STROBE_HW_SW_SEL_BIT, SW_STROBE_VAL);
+		else
+			strobe_sel = FIELD_PREP(FLASH_STROBE_HW_SW_SEL_BIT, HW_STROBE_VAL);
+
+		strobe_sel |=
+			FIELD_PREP(FLASH_HW_STROBE_TRIGGER_SEL_BIT, STROBE_LEVEL_TRIGGER_VAL) |
+			FIELD_PREP(FLASH_STROBE_POLARITY_BIT, STROBE_ACTIVE_HIGH_VAL);
+
+		rc = regmap_fields_write(
+				flash_data->r_fields[REG_CHAN_STROBE], chan_id, strobe_sel);
+		if (rc)
+			return rc;
+
+		chan_mask |= BIT(chan_id);
+	}
+
+	/* Enable/disable flash channels */
+	chan_en = state ? chan_mask : 0;
+	rc = regmap_field_update_bits(flash_data->r_fields[REG_CHAN_EN], chan_mask, chan_en);
+	if (rc)
+		return rc;
+
+	led->enabled = state;
+	return 0;
+}
+
+static inline struct qcom_flash_led *flcdev_to_qcom_fled(struct led_classdev_flash *flcdev)
+{
+	return container_of(flcdev, struct qcom_flash_led, flash);
+}
+
+static int qcom_flash_brightness_set(struct led_classdev_flash *fled_cdev, u32 brightness)
+{
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+
+	led->flash_current_ma = min_t(u32, led->max_flash_current_ma, brightness / UA_PER_MA);
+	return 0;
+}
+
+static int qcom_flash_timeout_set(struct led_classdev_flash *fled_cdev, u32 timeout)
+{
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+
+	led->flash_timeout_ms = timeout / USEC_PER_MSEC;
+	return 0;
+}
+
+static int qcom_flash_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
+{
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+	int rc;
+
+	rc = set_flash_current(led, led->flash_current_ma, FLASH_MODE);
+	if (rc)
+		return rc;
+
+	rc = set_flash_timeout(led, led->flash_timeout_ms);
+	if (rc)
+		return rc;
+
+	rc = set_flash_module_en(led, state);
+	if (rc)
+		return rc;
+
+	return set_flash_strobe(led, SW_STROBE, state);
+}
+
+static int qcom_flash_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
+{
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+
+	*state = led->enabled;
+	return 0;
+}
+
+static int qcom_flash_fault_get(struct led_classdev_flash *fled_cdev, u32 *fault)
+{
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+	struct qcom_flash_data *flash_data = led->flash_data;
+	u8 shift, chan_id, chan_mask = 0;
+	u8 ot_mask = 0, oc_mask = 0, uv_mask = 0;
+	u32 val, fault_sts = 0;
+	int i, rc;
+
+	rc = regmap_field_read(flash_data->r_fields[REG_STATUS1], &val);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < led->chan_count; i++) {
+		chan_id = led->chan_id[i];
+		shift = chan_id * 2;
+
+		if (val & BIT(shift))
+			fault_sts |= LED_FAULT_SHORT_CIRCUIT;
+
+		chan_mask |= BIT(chan_id);
+	}
+
+	rc = regmap_field_read(flash_data->r_fields[REG_STATUS2], &val);
+	if (rc)
+		return rc;
+
+	if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
+		ot_mask = FLASH_STS_3CH_OTST1 |
+			  FLASH_STS_3CH_OTST2 |
+			  FLASH_STS_3CH_OTST3 |
+			  FLASH_STS_3CH_BOB_THM_OVERLOAD;
+		oc_mask = FLASH_STS_3CH_BOB_ILIM_S1 |
+			  FLASH_STS_3CH_BOB_ILIM_S2 |
+			  FLASH_STS_3CH_BCL_IBAT;
+		uv_mask = FLASH_STS_3CH_VPH_DROOP;
+	} else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
+		ot_mask = FLASH_STS_4CH_OTST2 |
+			  FLASH_STS_4CH_OTST1 |
+			  FLASH_STS_4CHG_BOB_THM_OVERLOAD;
+		oc_mask = FLASH_STS_4CH_BCL_IBAT |
+			  FLASH_STS_4CH_BOB_ILIM_S1 |
+			  FLASH_STS_4CH_BOB_ILIM_S2;
+		uv_mask = FLASH_STS_4CH_VPH_LOW;
+	}
+
+	if (val & ot_mask)
+		fault_sts |= LED_FAULT_OVER_TEMPERATURE;
+
+	if (val & oc_mask)
+		fault_sts |= LED_FAULT_OVER_CURRENT;
+
+	if (val & uv_mask)
+		fault_sts |= LED_FAULT_INPUT_VOLTAGE;
+
+	rc = regmap_field_read(flash_data->r_fields[REG_STATUS3], &val);
+	if (rc)
+		return rc;
+
+	if (flash_data->hw_type == QCOM_MVFLASH_3CH) {
+		if (val & chan_mask)
+			fault_sts |= LED_FAULT_TIMEOUT;
+	} else if (flash_data->hw_type == QCOM_MVFLASH_4CH) {
+		for (i = 0; i < led->chan_count; i++) {
+			chan_id = led->chan_id[i];
+			shift = chan_id * 2;
+
+			if (val & BIT(shift))
+				fault_sts |= LED_FAULT_TIMEOUT;
+		}
+	}
+
+	*fault = fault_sts;
+	return 0;
+}
+
+static int qcom_flash_led_brightness_set(struct led_classdev *led_cdev,
+					enum led_brightness brightness)
+{
+	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+	u32 current_ma = brightness * led->max_torch_current_ma / LED_FULL;
+	bool enable = !!brightness;
+	int rc;
+
+	rc = set_flash_current(led, current_ma, TORCH_MODE);
+	if (rc)
+		return rc;
+
+	/* Disable flash timeout for torch LED */
+	rc = set_flash_timeout(led, 0);
+	if (rc)
+		return rc;
+
+	rc = set_flash_module_en(led, enable);
+	if (rc)
+		return rc;
+
+	return set_flash_strobe(led, SW_STROBE, enable);
+}
+
+static const struct led_flash_ops qcom_flash_ops = {
+	.flash_brightness_set = qcom_flash_brightness_set,
+	.strobe_set = qcom_flash_strobe_set,
+	.strobe_get = qcom_flash_strobe_get,
+	.timeout_set = qcom_flash_timeout_set,
+	.fault_get = qcom_flash_fault_get,
+};
+
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+static int qcom_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+	int rc;
+
+	rc = set_flash_module_en(led, enable);
+	if (rc)
+		return rc;
+
+	if (enable)
+		return set_flash_strobe(led, HW_STROBE, true);
+	else
+		return set_flash_strobe(led, SW_STROBE, false);
+}
+
+static enum led_brightness
+qcom_flash_intensity_to_led_brightness(struct v4l2_flash *v4l2_flash, s32 intensity)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+	u32 current_ma = intensity / UA_PER_MA;
+
+	current_ma = min_t(u32, current_ma, led->max_torch_current_ma);
+	if (!current_ma)
+		return LED_OFF;
+
+	return (current_ma * LED_FULL) / led->max_torch_current_ma;
+}
+
+static s32 qcom_flash_brightness_to_led_intensity(struct v4l2_flash *v4l2_flash,
+					enum led_brightness brightness)
+{
+	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
+	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
+
+	return (brightness * led->max_torch_current_ma * UA_PER_MA) / LED_FULL;
+}
+
+static const struct v4l2_flash_ops qcom_v4l2_flash_ops = {
+	.external_strobe_set = qcom_flash_external_strobe_set,
+	.intensity_to_led_brightness = qcom_flash_intensity_to_led_brightness,
+	.led_brightness_to_intensity = qcom_flash_brightness_to_led_intensity,
+};
+
+static int
+qcom_flash_v4l2_init(struct device *dev, struct qcom_flash_led *led, struct fwnode_handle *fwnode)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	struct v4l2_flash_config v4l2_cfg = { 0 };
+	struct led_flash_setting *intensity = &v4l2_cfg.intensity;
+
+	if (!(led->flash.led_cdev.flags & LED_DEV_CAP_FLASH))
+		return 0;
+
+	intensity->min = intensity->step = TORCH_IRES_UA * led->chan_count;
+	intensity->max = led->max_torch_current_ma * UA_PER_MA;
+	intensity->val = min_t(u32, intensity->max, TORCH_CURRENT_DEFAULT_UA);
+
+	strscpy(v4l2_cfg.dev_name, led->flash.led_cdev.dev->kobj.name,
+					sizeof(v4l2_cfg.dev_name));
+
+	v4l2_cfg.has_external_strobe = true;
+	v4l2_cfg.flash_faults = LED_FAULT_INPUT_VOLTAGE |
+				LED_FAULT_OVER_CURRENT |
+				LED_FAULT_SHORT_CIRCUIT |
+				LED_FAULT_OVER_TEMPERATURE |
+				LED_FAULT_TIMEOUT;
+
+	flash_data->v4l2_flash[flash_data->leds_count] =
+		v4l2_flash_init(dev, fwnode, &led->flash, &qcom_v4l2_flash_ops, &v4l2_cfg);
+	return PTR_ERR_OR_ZERO(flash_data->v4l2_flash);
+}
+# else
+static int
+qcom_flash_v4l2_init(struct device *dev, struct qcom_flash_led *led, struct fwnode_handle *fwnode)
+{
+	return 0;
+}
+#endif
+
+static int qcom_flash_register_led_device(struct device *dev,
+		struct fwnode_handle *node, struct qcom_flash_led *led)
+{
+	struct qcom_flash_data *flash_data = led->flash_data;
+	struct led_init_data init_data;
+	struct led_classdev_flash *flash = &led->flash;
+	struct led_flash_setting *brightness, *timeout;
+	u32 count, current_ua, timeout_us;
+	u32 channels[4];
+	int i, rc;
+
+	count = fwnode_property_count_u32(node, "led-sources");
+	if (count <= 0) {
+		dev_err(dev, "No led-sources specified\n");
+		return -ENODEV;
+	}
+
+	if (count > flash_data->max_channels) {
+		dev_err(dev, "led-sources count %u exceeds maximum channel count %u\n",
+				count, flash_data->max_channels);
+		return -EINVAL;
+	}
+
+	rc = fwnode_property_read_u32_array(node, "led-sources", channels, count);
+	if (rc < 0) {
+		dev_err(dev, "Failed to read led-sources property, rc=%d\n", rc);
+		return rc;
+	}
+
+	led->chan_count = count;
+	led->chan_id = devm_kcalloc(dev, count, sizeof(u8), GFP_KERNEL);
+	if (!led->chan_id)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		if ((channels[i] == 0) || (channels[i] > flash_data->max_channels)) {
+			dev_err(dev, "led-source out of HW support range [1-%u]\n",
+					flash_data->max_channels);
+			return -EINVAL;
+		}
+
+		/* Make chan_id indexing from 0 */
+		led->chan_id[i] = channels[i] - 1;
+	}
+
+	rc = fwnode_property_read_u32(node, "led-max-microamp", &current_ua);
+	if (rc < 0) {
+		dev_err(dev, "Failed to read led-max-microamp property, rc=%d\n", rc);
+		return rc;
+	}
+
+	if (current_ua == 0) {
+		dev_err(dev, "led-max-microamp shouldn't be 0\n");
+		return -EINVAL;
+	}
+
+	current_ua = min_t(u32, current_ua, TORCH_CURRENT_MAX_UA * led->chan_count);
+	led->max_torch_current_ma = current_ua / UA_PER_MA;
+
+	if (fwnode_property_present(node, "flash-max-microamp")) {
+		flash->led_cdev.flags |= LED_DEV_CAP_FLASH;
+
+		rc = fwnode_property_read_u32(node, "flash-max-microamp", &current_ua);
+		if (rc < 0) {
+			dev_err(dev, "Failed to read flash-max-microamp property, rc=%d\n",
+					rc);
+			return rc;
+		}
+
+		current_ua = min_t(u32, current_ua, FLASH_CURRENT_MAX_UA * led->chan_count);
+		current_ua = min_t(u32, current_ua, FLASH_TOTAL_CURRENT_MAX_UA);
+
+		/* Initialize flash class LED device brightness settings */
+		brightness = &flash->brightness;
+		brightness->min = brightness->step = FLASH_IRES_UA * led->chan_count;
+		brightness->max = current_ua;
+		brightness->val = min_t(u32, current_ua, FLASH_CURRENT_DEFAULT_UA);
+
+		led->max_flash_current_ma = current_ua / UA_PER_MA;
+		led->flash_current_ma = brightness->val / UA_PER_MA;
+
+		rc = fwnode_property_read_u32(node, "flash-max-timeout-us", &timeout_us);
+		if (rc < 0) {
+			dev_err(dev, "Failed to read flash-max-timeout-us property, rc=%d\n",
+					rc);
+			return rc;
+		}
+
+		timeout_us = min_t(u32, timeout_us, FLASH_TIMEOUT_MAX_US);
+
+		/* Initialize flash class LED device timeout settings */
+		timeout = &flash->timeout;
+		timeout->min = timeout->step = FLASH_TIMEOUT_STEP_US;
+		timeout->val = timeout->max = timeout_us;
+
+		led->max_timeout_ms = led->flash_timeout_ms = timeout_us / USEC_PER_MSEC;
+
+		flash->ops = &qcom_flash_ops;
+	}
+
+	flash->led_cdev.brightness_set_blocking = qcom_flash_led_brightness_set;
+
+	init_data.fwnode = node;
+	init_data.devicename = NULL;
+	init_data.default_label = NULL;
+	init_data.devname_mandatory = false;
+
+	rc = devm_led_classdev_flash_register_ext(dev, flash, &init_data);
+	if (rc < 0) {
+		dev_err(dev, "Register flash LED classdev failed, rc=%d\n", rc);
+		return rc;
+	}
+
+	return qcom_flash_v4l2_init(dev, led, node);
+}
+
+static int qcom_flash_led_probe(struct platform_device *pdev)
+{
+	struct qcom_flash_data *flash_data;
+	struct qcom_flash_led *led;
+	struct fwnode_handle *child;
+	struct device *dev = &pdev->dev;
+	struct regmap *regmap;
+	struct reg_field *regs;
+	int count, i, rc;
+	u32 val, reg_base;
+
+	flash_data = devm_kzalloc(dev, sizeof(*flash_data), GFP_KERNEL);
+	if (!flash_data)
+		return -ENOMEM;
+
+	regmap = dev_get_regmap(dev->parent, NULL);
+	if (!regmap) {
+		dev_err(dev, "Failed to get parent regmap\n");
+		return -EINVAL;
+	}
+
+	rc = fwnode_property_read_u32(dev->fwnode, "reg", &reg_base);
+	if (rc < 0) {
+		dev_err(dev, "Failed to get register base address, rc=%d\n", rc);
+		return rc;
+	}
+
+	rc = regmap_read(regmap, reg_base + FLASH_TYPE_REG, &val);
+	if (rc < 0) {
+		dev_err(dev, "Read flash LED module type failed, rc=%d\n", rc);
+		return rc;
+	}
+
+	if (val != FLASH_TYPE_VAL) {
+		dev_err(dev, "type %#x is not a flash LED module\n", val);
+		return -ENODEV;
+	}
+
+	rc = regmap_read(regmap, reg_base + FLASH_SUBTYPE_REG, &val);
+	if (rc < 0) {
+		dev_err(dev, "Read flash LED module subtype failed, rc=%d\n", rc);
+		return rc;
+	}
+
+	if (val == FLASH_SUBTYPE_3CH_VAL) {
+		flash_data->hw_type = QCOM_MVFLASH_3CH;
+		flash_data->max_channels = 3;
+		regs = mvflash_3ch_regs;
+	} else if (val == FLASH_SUBTYPE_4CH_VAL) {
+		flash_data->hw_type = QCOM_MVFLASH_4CH;
+		flash_data->max_channels = 4;
+		regs = mvflash_4ch_regs;
+	} else {
+		dev_err(dev, "flash LED subtype %#x is not yet supported\n", val);
+		return -ENODEV;
+	}
+
+	for (i = 0; i < REG_MAX_COUNT; i++)
+		regs[i].reg += reg_base;
+
+	rc = devm_regmap_field_bulk_alloc(dev, regmap, flash_data->r_fields, regs, REG_MAX_COUNT);
+	if (rc < 0) {
+		dev_err(dev, "Failed to allocate regmap field, rc=%d\n", rc);
+		return rc;
+	}
+
+	platform_set_drvdata(pdev, flash_data);
+	mutex_init(&flash_data->lock);
+
+	count = device_get_child_node_count(dev);
+	if (count == 0 || count > flash_data->max_channels) {
+		dev_err(dev, "No child or child count exceeds %d\n", flash_data->max_channels);
+		return -EINVAL;
+	}
+
+	flash_data->v4l2_flash = devm_kcalloc(dev, count,
+			sizeof(*flash_data->v4l2_flash), GFP_KERNEL);
+	if (!flash_data->v4l2_flash)
+		return -ENOMEM;
+
+	device_for_each_child_node(dev, child) {
+		led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
+		if (!led) {
+			rc = -ENOMEM;
+			goto release;
+		}
+
+		led->flash_data = flash_data;
+		rc = qcom_flash_register_led_device(dev, child, led);
+		if (rc < 0)
+			goto release;
+
+		flash_data->leds_count++;
+	}
+
+	return 0;
+
+release:
+	while (flash_data->v4l2_flash[flash_data->leds_count] && flash_data->leds_count)
+		v4l2_flash_release(flash_data->v4l2_flash[flash_data->leds_count--]);
+	return rc;
+}
+
+static int qcom_flash_led_remove(struct platform_device *pdev)
+{
+	struct qcom_flash_data *flash_data = platform_get_drvdata(pdev);
+
+	while (flash_data->v4l2_flash[flash_data->leds_count] && flash_data->leds_count)
+		v4l2_flash_release(flash_data->v4l2_flash[flash_data->leds_count--]);
+
+	mutex_destroy(&flash_data->lock);
+	return 0;
+}
+
+static const struct of_device_id qcom_flash_led_match_table[] = {
+	{ .compatible = "qcom,spmi-flash-led" },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, qcom_flash_led_match_table);
+static struct platform_driver qcom_flash_led_driver = {
+	.driver = {
+		.name = "leds-qcom-flash",
+		.of_match_table = qcom_flash_led_match_table,
+	},
+	.probe = qcom_flash_led_probe,
+	.remove = qcom_flash_led_remove,
+};
+
+module_platform_driver(qcom_flash_led_driver);
+
+MODULE_DESCRIPTION("QCOM Flash LED driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1

[PATCH v8 2/2] dt-bindings: leds: add QCOM flash LED controller

[Fenglin Wu]

Add binding document for flash LED module inside Qualcomm Technologies,
Inc. PMICs.

Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../bindings/leds/qcom,spmi-flash-led.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml

diff --git a/Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml b/Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml
new file mode 100644
index 000000000000..1b273aecaaec
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml
@@ -0,0 +1,116 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/qcom,spmi-flash-led.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Flash LED device inside Qualcomm Technologies, Inc. PMICs
+
+maintainers:
+  - Fenglin Wu <quic_fenglinw@quicinc.com>
+
+description: |
+  Flash LED controller is present inside some Qualcomm Technologies, Inc. PMICs.
+  The flash LED module can have different number of LED channels supported
+  e.g. 3 or 4. There are some different registers between them but they can
+  both support maximum current up to 1.5 A per channel and they can also support
+  ganging 2 channels together to supply maximum current up to 2 A. The current
+  will be split symmetrically on each channel and they will be enabled and
+  disabled at the same time.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - qcom,pm8150c-flash-led
+          - qcom,pm8150l-flash-led
+          - qcom,pm8350c-flash-led
+      - const: qcom,spmi-flash-led
+
+  reg:
+    maxItems: 1
+
+patternProperties:
+  "^led-[0-3]$":
+    type: object
+    $ref: common.yaml#
+    unevaluatedProperties: false
+    description:
+      Represents the physical LED components which are connected to the
+      flash LED channels' output.
+
+    properties:
+      led-sources:
+        description:
+          The HW indices of the flash LED channels that connect to the
+          physical LED
+        allOf:
+          - minItems: 1
+            maxItems: 2
+            items:
+              enum: [1, 2, 3, 4]
+
+      led-max-microamp:
+        anyOf:
+          - minimum: 5000
+            maximum: 500000
+            multipleOf: 5000
+          - minimum: 10000
+            maximum: 1000000
+            multipleOf: 10000
+
+      flash-max-microamp:
+        anyOf:
+          - minimum: 12500
+            maximum: 1500000
+            multipleOf: 12500
+          - minimum: 25000
+            maximum: 2000000
+            multipleOf: 25000
+
+      flash-max-timeout-us:
+        minimum: 10000
+        maximum: 1280000
+        multipleOf: 10000
+
+    required:
+      - led-sources
+      - led-max-microamp
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+    spmi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        led-controller@ee00 {
+            compatible = "qcom,pm8350c-flash-led", "qcom,spmi-flash-led";
+            reg = <0xee00>;
+
+            led-0 {
+                function = LED_FUNCTION_FLASH;
+                color = <LED_COLOR_ID_WHITE>;
+                led-sources = <1>, <4>;
+                led-max-microamp = <300000>;
+                flash-max-microamp = <2000000>;
+                flash-max-timeout-us = <1280000>;
+                function-enumerator = <0>;
+            };
+
+            led-1 {
+                function = LED_FUNCTION_FLASH;
+                color = <LED_COLOR_ID_YELLOW>;
+                led-sources = <2>, <3>;
+                led-max-microamp = <300000>;
+                flash-max-microamp = <2000000>;
+                flash-max-timeout-us = <1280000>;
+                function-enumerator = <1>;
+            };
+        };
+    };
-- 
2.25.1

Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Lee Jones]

On Fri, 03 Mar 2023, Fenglin Wu wrote:

> Add initial driver to support flash LED module found in Qualcomm
> Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
> and each channel can be controlled indepedently and support full scale
> current up to 1.5 A. It also supports connecting two channels together
> to supply one LED component with full scale current up to 2 A. In that
> case, the current will be split on each channel symmetrically and the
> channels will be enabled and disabled at the same time.
>
> Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
> Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sm7225-fairphone-fp4 + pm6150l
> ---
>  drivers/leds/flash/Kconfig           |  15 +
>  drivers/leds/flash/Makefile          |   1 +
>  drivers/leds/flash/leds-qcom-flash.c | 773 +++++++++++++++++++++++++++
>  3 files changed, 789 insertions(+)
>  create mode 100644 drivers/leds/flash/leds-qcom-flash.c

Applied, thanks

--
Lee Jones [李琼斯]

Re: [PATCH v8 2/2] dt-bindings: leds: add QCOM flash LED controller

[Lee Jones]

On Fri, 03 Mar 2023, Fenglin Wu wrote:

> Add binding document for flash LED module inside Qualcomm Technologies,
> Inc. PMICs.
>
> Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>  .../bindings/leds/qcom,spmi-flash-led.yaml    | 116 ++++++++++++++++++
>  1 file changed, 116 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/qcom,spmi-flash-led.yaml

Applied, thanks

--
Lee Jones [李琼斯]

Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Pavel Machek]

Hi!
> @@ -61,6 +61,21 @@ config LEDS_MT6360
>  	  Independent current sources supply for each flash LED support torch
>  	  and strobe mode.
>  
> +config LEDS_QCOM_FLASH
> +	tristate "LED support for flash module inside Qualcomm Technologies, Inc. PMIC"
> +	depends on MFD_SPMI_PMIC || COMPILE_TEST
> +	depends on LEDS_CLASS && OF
> +	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
> +	select REGMAP
> +	help
> +	  This option enables support for the flash module found in Qualcomm
> +	  Technologies, Inc. PMICs. The flash module can have 3 or 4 flash LED
> +	  channels and each channel is programmable to support up to 1.5 A full
> +	  scale current. It also supports connecting two channels' output together
> +	  to supply one LED component to achieve current up to 2 A. In such case,
> +	  the total LED current will be split symmetrically on each channel and
> +	  they will be enabled/disabled at the same time.

"This can be built as a module, module will be called..."

> +static int qcom_flash_led_brightness_set(struct led_classdev *led_cdev,
> +					enum led_brightness brightness)
> +{
> +	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
> +	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
> +	u32 current_ma = brightness * led->max_torch_current_ma / LED_FULL;
> +	bool enable = !!brightness;
> +	int rc;
> +
> +	rc = set_flash_current(led, current_ma, TORCH_MODE);
> +	if (rc)
> +		return rc;

I'd not mind supporting more than one brightness level -- AFAICT hw can do that.

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

Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1827 bytes --]

Hi!

> Add initial driver to support flash LED module found in Qualcomm
> Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
> and each channel can be controlled indepedently and support full scale
> current up to 1.5 A. It also supports connecting two channels together
> to supply one LED component with full scale current up to 2 A. In that
> case, the current will be split on each channel symmetrically and the
> channels will be enabled and disabled at the same time.


> +static int qcom_flash_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
> +{
> +	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
> +	int rc;
> +
> +	rc = set_flash_current(led, led->flash_current_ma, FLASH_MODE);
> +	if (rc)
> +		return rc;
> +
> +	rc = set_flash_timeout(led, led->flash_timeout_ms);
> +	if (rc)
> +		return rc;
> +
> +	rc = set_flash_module_en(led, state);
> +	if (rc)
> +		return rc;
> +
> +	return set_flash_strobe(led, SW_STROBE, state);
> +}

Should we disable the module before setting the current? It might be
already active due to torch mode...


> +		return -EINVAL;
> +	}
> +
> +	flash_data->v4l2_flash = devm_kcalloc(dev, count,
> +			sizeof(*flash_data->v4l2_flash), GFP_KERNEL);
> +	if (!flash_data->v4l2_flash)
> +		return -ENOMEM;
> +
> +	device_for_each_child_node(dev, child) {
> +		led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
> +		if (!led) {
> +			rc = -ENOMEM;
> +			goto release;
> +		}
> +
> +		led->flash_data = flash_data;
> +		rc = qcom_flash_register_led_device(dev, child, led);
> +		if (rc < 0)
> +			goto release;
> +
> +		flash_data->leds_count++;
> +	}

Do you need to do of_node_put in error paths?

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

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Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Pavel Machek]

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On Fri 2023-03-03 17:50:22, Fenglin Wu wrote:
> Add initial driver to support flash LED module found in Qualcomm
> Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
> and each channel can be controlled indepedently and support full scale
> current up to 1.5 A. It also supports connecting two channels together
> to supply one LED component with full scale current up to 2 A. In that
> case, the current will be split on each channel symmetrically and the
> channels will be enabled and disabled at the same time.
> 
> Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
> Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sm7225-fairphone-fp4 + pm6150l

> +	flash->led_cdev.brightness_set_blocking = qcom_flash_led_brightness_set;
> +
> +	init_data.fwnode = node;
> +	init_data.devicename = NULL;
> +	init_data.default_label = NULL;
> +	init_data.devname_mandatory = false;
> +
> +	rc = devm_led_classdev_flash_register_ext(dev, flash, &init_data);
> +	if (rc < 0) {
> +		dev_err(dev, "Register flash LED classdev failed, rc=%d\n", rc);
> +		return rc;
> +	}

I'd expect setting max_brightness somewhere around here.

What does cat /sys/class/leds/*/max_brightness say (and what directory
name are you using)?

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

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Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Fenglin Wu]

On 3/26/2023 1:09 AM, Pavel Machek wrote:
> Hi!
>> @@ -61,6 +61,21 @@ config LEDS_MT6360
>>   	  Independent current sources supply for each flash LED support torch
>>   	  and strobe mode.
>>   
>> +config LEDS_QCOM_FLASH
>> +	tristate "LED support for flash module inside Qualcomm Technologies, Inc. PMIC"
>> +	depends on MFD_SPMI_PMIC || COMPILE_TEST
>> +	depends on LEDS_CLASS && OF
>> +	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
>> +	select REGMAP
>> +	help
>> +	  This option enables support for the flash module found in Qualcomm
>> +	  Technologies, Inc. PMICs. The flash module can have 3 or 4 flash LED
>> +	  channels and each channel is programmable to support up to 1.5 A full
>> +	  scale current. It also supports connecting two channels' output together
>> +	  to supply one LED component to achieve current up to 2 A. In such case,
>> +	  the total LED current will be split symmetrically on each channel and
>> +	  they will be enabled/disabled at the same time.
> 
> "This can be built as a module, module will be called..."

I can update it in a new change considering the initial change has been 
applied.

> 
>> +static int qcom_flash_led_brightness_set(struct led_classdev *led_cdev,
>> +					enum led_brightness brightness)
>> +{
>> +	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
>> +	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
>> +	u32 current_ma = brightness * led->max_torch_current_ma / LED_FULL;
>> +	bool enable = !!brightness;
>> +	int rc;
>> +
>> +	rc = set_flash_current(led, current_ma, TORCH_MODE);
>> +	if (rc)
>> +		return rc;
> 
> I'd not mind supporting more than one brightness level -- AFAICT hw can do that.

It does support multiple levels and the 'current_ma' is calculated based 
on different brightness level.

> 
> BR,
> 									Pavel

Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Fenglin Wu]

On 3/26/2023 1:33 AM, Pavel Machek wrote:
> Hi!
> 
>> Add initial driver to support flash LED module found in Qualcomm
>> Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
>> and each channel can be controlled indepedently and support full scale
>> current up to 1.5 A. It also supports connecting two channels together
>> to supply one LED component with full scale current up to 2 A. In that
>> case, the current will be split on each channel symmetrically and the
>> channels will be enabled and disabled at the same time.
> 
> 
>> +static int qcom_flash_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
>> +{
>> +	struct qcom_flash_led *led = flcdev_to_qcom_fled(fled_cdev);
>> +	int rc;
>> +
>> +	rc = set_flash_current(led, led->flash_current_ma, FLASH_MODE);
>> +	if (rc)
>> +		return rc;
>> +
>> +	rc = set_flash_timeout(led, led->flash_timeout_ms);
>> +	if (rc)
>> +		return rc;
>> +
>> +	rc = set_flash_module_en(led, state);
>> +	if (rc)
>> +		return rc;
>> +
>> +	return set_flash_strobe(led, SW_STROBE, state);
>> +}
> 
> Should we disable the module before setting the current? It might be
> already active due to torch mode...
> 
The module enabling status should be kept as it is because it may be 
still controlling other LED channels, I can strobe off the LED before 
setting the current to cover such case. I will update it as a following 
patch.

> 
>> +		return -EINVAL;
>> +	}
>> +
>> +	flash_data->v4l2_flash = devm_kcalloc(dev, count,
>> +			sizeof(*flash_data->v4l2_flash), GFP_KERNEL);
>> +	if (!flash_data->v4l2_flash)
>> +		return -ENOMEM;
>> +
>> +	device_for_each_child_node(dev, child) {
>> +		led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
>> +		if (!led) {
>> +			rc = -ENOMEM;
>> +			goto release;
>> +		}
>> +
>> +		led->flash_data = flash_data;
>> +		rc = qcom_flash_register_led_device(dev, child, led);
>> +		if (rc < 0)
>> +			goto release;
>> +
>> +		flash_data->leds_count++;
>> +	}
> 
> Do you need to do of_node_put in error path
I will update this as well.

> 
> BR,
> 							Pavel

Re: [PATCH v8 1/2] leds: flash: add driver to support flash LED module in QCOM PMICs

[Fenglin Wu]

On 3/26/2023 1:36 AM, Pavel Machek wrote:
> On Fri 2023-03-03 17:50:22, Fenglin Wu wrote:
>> Add initial driver to support flash LED module found in Qualcomm
>> Technologies, Inc. PMICs. The flash module can have 3 or 4 channels
>> and each channel can be controlled indepedently and support full scale
>> current up to 1.5 A. It also supports connecting two channels together
>> to supply one LED component with full scale current up to 2 A. In that
>> case, the current will be split on each channel symmetrically and the
>> channels will be enabled and disabled at the same time.
>>
>> Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
>> Tested-by: Luca Weiss <luca.weiss@fairphone.com> # sm7225-fairphone-fp4 + pm6150l
> 
>> +	flash->led_cdev.brightness_set_blocking = qcom_flash_led_brightness_set;
>> +
>> +	init_data.fwnode = node;
>> +	init_data.devicename = NULL;
>> +	init_data.default_label = NULL;
>> +	init_data.devname_mandatory = false;
>> +
>> +	rc = devm_led_classdev_flash_register_ext(dev, flash, &init_data);
>> +	if (rc < 0) {
>> +		dev_err(dev, "Register flash LED classdev failed, rc=%d\n", rc);
>> +		return rc;
>> +	}
> 
> I'd expect setting max_brightness somewhere around here.
> 
> What does cat /sys/class/leds/*/max_brightness say (and what directory
> name are you using)?

LED_FULL is used as the default max_brightness, the driver will do the 
calculation based on LED_FULL (as below) and set the corresponding 
current when brightness is updated :

u32 current_ma = brightness * led->max_torch_current_ma / LED_FULL;

This is how max_brightness shows on my device:

# cat /sys/class/leds/white:flash-0/max_brightness
255

> 
> BR,								Pavel