[PATCH V6 1/8] backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c

[PATCH V6 1/8] backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c

[Kiran Gunda]

pm8941-wled.c driver is supporting the WLED peripheral
on pm8941. Rename it to qcom-wled.c so that it can support
WLED on multiple PMICs.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
---
 .../bindings/leds/backlight/{pm8941-wled.txt => qcom-wled.txt}    | 2 +-
 drivers/video/backlight/Kconfig                                   | 8 ++++----
 drivers/video/backlight/Makefile                                  | 2 +-
 drivers/video/backlight/{pm8941-wled.c => qcom-wled.c}            | 0
 4 files changed, 6 insertions(+), 6 deletions(-)
 rename Documentation/devicetree/bindings/leds/backlight/{pm8941-wled.txt => qcom-wled.txt} (95%)
 rename drivers/video/backlight/{pm8941-wled.c => qcom-wled.c} (100%)

diff --git a/Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
similarity index 95%
rename from Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt
rename to Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
index e5b294d..fb39e32 100644
--- a/Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt
+++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
@@ -1,4 +1,4 @@
-Binding for Qualcomm PM8941 WLED driver
+Binding for Qualcomm Technologies, Inc. WLED driver
 
 Required properties:
 - compatible: should be "qcom,pm8941-wled"
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 8b081d6..6ff3176 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -284,12 +284,12 @@ config BACKLIGHT_TOSA
 	  If you have an Sharp SL-6000 Zaurus say Y to enable a driver
 	  for its backlight
 
-config BACKLIGHT_PM8941_WLED
-	tristate "Qualcomm PM8941 WLED Driver"
+config BACKLIGHT_QCOM_WLED
+	tristate "Qualcomm PMIC WLED Driver"
 	select REGMAP
 	help
-	  If you have the Qualcomm PM8941, say Y to enable a driver for the
-	  WLED block.
+	  If you have the Qualcomm PMIC, say Y to enable a driver for the
+	  WLED block. Currently it supports PM8941 and PMI8998.
 
 config BACKLIGHT_SAHARA
 	tristate "Tabletkiosk Sahara Touch-iT Backlight Driver"
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 63c507c..6f87770 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -48,8 +48,8 @@ obj-$(CONFIG_BACKLIGHT_OMAP1)		+= omap1_bl.o
 obj-$(CONFIG_BACKLIGHT_OT200)		+= ot200_bl.o
 obj-$(CONFIG_BACKLIGHT_PANDORA)		+= pandora_bl.o
 obj-$(CONFIG_BACKLIGHT_PCF50633)	+= pcf50633-backlight.o
-obj-$(CONFIG_BACKLIGHT_PM8941_WLED)	+= pm8941-wled.o
 obj-$(CONFIG_BACKLIGHT_PWM)		+= pwm_bl.o
+obj-$(CONFIG_BACKLIGHT_QCOM_WLED)	+= qcom-wled.o
 obj-$(CONFIG_BACKLIGHT_SAHARA)		+= kb3886_bl.o
 obj-$(CONFIG_BACKLIGHT_SKY81452)	+= sky81452-backlight.o
 obj-$(CONFIG_BACKLIGHT_TOSA)		+= tosa_bl.o
diff --git a/drivers/video/backlight/pm8941-wled.c b/drivers/video/backlight/qcom-wled.c
similarity index 100%
rename from drivers/video/backlight/pm8941-wled.c
rename to drivers/video/backlight/qcom-wled.c
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project

Re: [PATCH V6 1/8] backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c

[Dan Murphy]

Kiran

On 9/30/19 1:39 AM, Kiran Gunda wrote:
> pm8941-wled.c driver is supporting the WLED peripheral
> on pm8941. Rename it to qcom-wled.c so that it can support
> WLED on multiple PMICs.
>
> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> Acked-by: Rob Herring <robh@kernel.org>
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> ---
>   .../bindings/leds/backlight/{pm8941-wled.txt => qcom-wled.txt}    | 2 +-

Instead of renaming this file would it be more maintainable to indicate 
in the pm8941-wled.txt

to reference the qcom-wled.txt file for complete description?

I will let Rob comment on maintainability.

Dan

>   drivers/video/backlight/Kconfig                                   | 8 ++++----
>   drivers/video/backlight/Makefile                                  | 2 +-
>   drivers/video/backlight/{pm8941-wled.c => qcom-wled.c}            | 0
>   4 files changed, 6 insertions(+), 6 deletions(-)
>   rename Documentation/devicetree/bindings/leds/backlight/{pm8941-wled.txt => qcom-wled.txt} (95%)
>   rename drivers/video/backlight/{pm8941-wled.c => qcom-wled.c} (100%)
>
> diff --git a/Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
> similarity index 95%
> rename from Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt
> rename to Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
> index e5b294d..fb39e32 100644
> --- a/Documentation/devicetree/bindings/leds/backlight/pm8941-wled.txt
> +++ b/Documentation/devicetree/bindings/leds/backlight/qcom-wled.txt
> @@ -1,4 +1,4 @@
> -Binding for Qualcomm PM8941 WLED driver
> +Binding for Qualcomm Technologies, Inc. WLED driver
>   
>   Required properties:
>   - compatible: should be "qcom,pm8941-wled"
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index 8b081d6..6ff3176 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -284,12 +284,12 @@ config BACKLIGHT_TOSA
>   	  If you have an Sharp SL-6000 Zaurus say Y to enable a driver
>   	  for its backlight
>   
> -config BACKLIGHT_PM8941_WLED
> -	tristate "Qualcomm PM8941 WLED Driver"
> +config BACKLIGHT_QCOM_WLED
> +	tristate "Qualcomm PMIC WLED Driver"
>   	select REGMAP
>   	help
> -	  If you have the Qualcomm PM8941, say Y to enable a driver for the
> -	  WLED block.
> +	  If you have the Qualcomm PMIC, say Y to enable a driver for the
> +	  WLED block. Currently it supports PM8941 and PMI8998.
>   
>   config BACKLIGHT_SAHARA
>   	tristate "Tabletkiosk Sahara Touch-iT Backlight Driver"
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index 63c507c..6f87770 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -48,8 +48,8 @@ obj-$(CONFIG_BACKLIGHT_OMAP1)		+= omap1_bl.o
>   obj-$(CONFIG_BACKLIGHT_OT200)		+= ot200_bl.o
>   obj-$(CONFIG_BACKLIGHT_PANDORA)		+= pandora_bl.o
>   obj-$(CONFIG_BACKLIGHT_PCF50633)	+= pcf50633-backlight.o
> -obj-$(CONFIG_BACKLIGHT_PM8941_WLED)	+= pm8941-wled.o
>   obj-$(CONFIG_BACKLIGHT_PWM)		+= pwm_bl.o
> +obj-$(CONFIG_BACKLIGHT_QCOM_WLED)	+= qcom-wled.o
>   obj-$(CONFIG_BACKLIGHT_SAHARA)		+= kb3886_bl.o
>   obj-$(CONFIG_BACKLIGHT_SKY81452)	+= sky81452-backlight.o
>   obj-$(CONFIG_BACKLIGHT_TOSA)		+= tosa_bl.o
> diff --git a/drivers/video/backlight/pm8941-wled.c b/drivers/video/backlight/qcom-wled.c
> similarity index 100%
> rename from drivers/video/backlight/pm8941-wled.c
> rename to drivers/video/backlight/qcom-wled.c

[PATCH V6 4/8] backlight: qcom-wled: Rename PM8941* to WLED3

[Kiran Gunda]

Rename the PM8941* references as WLED3 to make the driver
generic and have WLED support for other PMICs. Also rename
"i_boost_limit" and "i_limit" variables to "boost_i_limit"
and "string_i_limit" respectively to resemble the corresponding
register names.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
---
 drivers/video/backlight/qcom-wled.c | 248 ++++++++++++++++++------------------
 1 file changed, 125 insertions(+), 123 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 82b8572..f191242 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -10,77 +10,79 @@
 #include <linux/regmap.h>
 
 /* From DT binding */
-#define PM8941_WLED_DEFAULT_BRIGHTNESS		2048
+#define WLED_DEFAULT_BRIGHTNESS				2048
 
-#define PM8941_WLED_REG_VAL_BASE		0x40
-#define  PM8941_WLED_REG_VAL_MAX		0xFFF
+#define WLED3_SINK_REG_BRIGHT_MAX			0xFFF
+#define WLED3_CTRL_REG_VAL_BASE				0x40
 
-#define PM8941_WLED_REG_MOD_EN			0x46
-#define  PM8941_WLED_REG_MOD_EN_BIT		BIT(7)
-#define  PM8941_WLED_REG_MOD_EN_MASK		BIT(7)
+/* WLED3 control registers */
+#define WLED3_CTRL_REG_MOD_EN				0x46
+#define  WLED3_CTRL_REG_MOD_EN_BIT			BIT(7)
+#define  WLED3_CTRL_REG_MOD_EN_MASK			BIT(7)
 
-#define PM8941_WLED_REG_SYNC			0x47
-#define  PM8941_WLED_REG_SYNC_MASK		0x07
-#define  PM8941_WLED_REG_SYNC_LED1		BIT(0)
-#define  PM8941_WLED_REG_SYNC_LED2		BIT(1)
-#define  PM8941_WLED_REG_SYNC_LED3		BIT(2)
-#define  PM8941_WLED_REG_SYNC_ALL		0x07
-#define  PM8941_WLED_REG_SYNC_CLEAR		0x00
+#define WLED3_CTRL_REG_FREQ				0x4c
+#define  WLED3_CTRL_REG_FREQ_MASK			0x0f
 
-#define PM8941_WLED_REG_FREQ			0x4c
-#define  PM8941_WLED_REG_FREQ_MASK		0x0f
+#define WLED3_CTRL_REG_OVP				0x4d
+#define  WLED3_CTRL_REG_OVP_MASK			0x03
 
-#define PM8941_WLED_REG_OVP			0x4d
-#define  PM8941_WLED_REG_OVP_MASK		0x03
+#define WLED3_CTRL_REG_ILIMIT				0x4e
+#define  WLED3_CTRL_REG_ILIMIT_MASK			0x07
 
-#define PM8941_WLED_REG_BOOST			0x4e
-#define  PM8941_WLED_REG_BOOST_MASK		0x07
+/* WLED3 sink registers */
+#define WLED3_SINK_REG_SYNC				0x47
+#define  WLED3_SINK_REG_SYNC_MASK			0x07
+#define  WLED3_SINK_REG_SYNC_LED1			BIT(0)
+#define  WLED3_SINK_REG_SYNC_LED2			BIT(1)
+#define  WLED3_SINK_REG_SYNC_LED3			BIT(2)
+#define  WLED3_SINK_REG_SYNC_ALL			0x07
+#define  WLED3_SINK_REG_SYNC_CLEAR			0x00
 
-#define PM8941_WLED_REG_SINK			0x4f
-#define  PM8941_WLED_REG_SINK_MASK		0xe0
-#define  PM8941_WLED_REG_SINK_SHFT		0x05
+#define WLED3_SINK_REG_CURR_SINK			0x4f
+#define  WLED3_SINK_REG_CURR_SINK_MASK			0xe0
+#define  WLED3_SINK_REG_CURR_SINK_SHFT			0x05
 
-/* Per-'string' registers below */
-#define PM8941_WLED_REG_STR_OFFSET		0x10
+/* WLED3 per-'string' registers below */
+#define WLED3_SINK_REG_STR_OFFSET			0x10
 
-#define PM8941_WLED_REG_STR_MOD_EN_BASE		0x60
-#define  PM8941_WLED_REG_STR_MOD_MASK		BIT(7)
-#define  PM8941_WLED_REG_STR_MOD_EN		BIT(7)
+#define WLED3_SINK_REG_STR_MOD_EN_BASE			0x60
+#define  WLED3_SINK_REG_STR_MOD_MASK			BIT(7)
+#define  WLED3_SINK_REG_STR_MOD_EN			BIT(7)
 
-#define PM8941_WLED_REG_STR_SCALE_BASE		0x62
-#define  PM8941_WLED_REG_STR_SCALE_MASK		0x1f
+#define WLED3_SINK_REG_STR_FULL_SCALE_CURR		0x62
+#define  WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK	0x1f
 
-#define PM8941_WLED_REG_STR_MOD_SRC_BASE	0x63
-#define  PM8941_WLED_REG_STR_MOD_SRC_MASK	0x01
-#define  PM8941_WLED_REG_STR_MOD_SRC_INT	0x00
-#define  PM8941_WLED_REG_STR_MOD_SRC_EXT	0x01
+#define WLED3_SINK_REG_STR_MOD_SRC_BASE			0x63
+#define  WLED3_SINK_REG_STR_MOD_SRC_MASK		0x01
+#define  WLED3_SINK_REG_STR_MOD_SRC_INT			0x00
+#define  WLED3_SINK_REG_STR_MOD_SRC_EXT			0x01
 
-#define PM8941_WLED_REG_STR_CABC_BASE		0x66
-#define  PM8941_WLED_REG_STR_CABC_MASK		BIT(7)
-#define  PM8941_WLED_REG_STR_CABC_EN		BIT(7)
+#define WLED3_SINK_REG_STR_CABC_BASE			0x66
+#define  WLED3_SINK_REG_STR_CABC_MASK			BIT(7)
+#define  WLED3_SINK_REG_STR_CABC_EN			BIT(7)
 
-struct pm8941_wled_config {
-	u32 i_boost_limit;
+struct wled_config {
+	u32 boost_i_limit;
 	u32 ovp;
 	u32 switch_freq;
 	u32 num_strings;
-	u32 i_limit;
+	u32 string_i_limit;
 	bool cs_out_en;
 	bool ext_gen;
 	bool cabc_en;
 };
 
-struct pm8941_wled {
+struct wled {
 	const char *name;
 	struct regmap *regmap;
 	u16 addr;
 
-	struct pm8941_wled_config cfg;
+	struct wled_config cfg;
 };
 
-static int pm8941_wled_update_status(struct backlight_device *bl)
+static int wled_update_status(struct backlight_device *bl)
 {
-	struct pm8941_wled *wled = bl_get_data(bl);
+	struct wled *wled = bl_get_data(bl);
 	u16 val = bl->props.brightness;
 	u8 ctrl = 0;
 	int rc;
@@ -92,11 +94,11 @@ static int pm8941_wled_update_status(struct backlight_device *bl)
 		val = 0;
 
 	if (val != 0)
-		ctrl = PM8941_WLED_REG_MOD_EN_BIT;
+		ctrl = WLED3_CTRL_REG_MOD_EN_BIT;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_MOD_EN,
-			PM8941_WLED_REG_MOD_EN_MASK, ctrl);
+			wled->addr + WLED3_CTRL_REG_MOD_EN,
+			WLED3_CTRL_REG_MOD_EN_MASK, ctrl);
 	if (rc)
 		return rc;
 
@@ -104,89 +106,89 @@ static int pm8941_wled_update_status(struct backlight_device *bl)
 		u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
 
 		rc = regmap_bulk_write(wled->regmap,
-				wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
+				wled->addr + WLED3_CTRL_REG_VAL_BASE + 2 * i,
 				v, 2);
 		if (rc)
 			return rc;
 	}
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_SYNC,
-			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
+			wled->addr + WLED3_SINK_REG_SYNC,
+			WLED3_SINK_REG_SYNC_MASK, WLED3_SINK_REG_SYNC_ALL);
 	if (rc)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_SYNC,
-			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
+			wled->addr + WLED3_SINK_REG_SYNC,
+			WLED3_SINK_REG_SYNC_MASK, WLED3_SINK_REG_SYNC_CLEAR);
 	return rc;
 }
 
-static int pm8941_wled_setup(struct pm8941_wled *wled)
+static int wled_setup(struct wled *wled)
 {
 	int rc;
 	int i;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_OVP,
-			PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
+			wled->addr + WLED3_CTRL_REG_OVP,
+			WLED3_CTRL_REG_OVP_MASK, wled->cfg.ovp);
 	if (rc)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_BOOST,
-			PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
+			wled->addr + WLED3_CTRL_REG_ILIMIT,
+			WLED3_CTRL_REG_ILIMIT_MASK, wled->cfg.boost_i_limit);
 	if (rc)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_FREQ,
-			PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
+			wled->addr + WLED3_CTRL_REG_FREQ,
+			WLED3_CTRL_REG_FREQ_MASK, wled->cfg.switch_freq);
 	if (rc)
 		return rc;
 
 	if (wled->cfg.cs_out_en) {
 		u8 all = (BIT(wled->cfg.num_strings) - 1)
-				<< PM8941_WLED_REG_SINK_SHFT;
+				<< WLED3_SINK_REG_CURR_SINK_SHFT;
 
 		rc = regmap_update_bits(wled->regmap,
-				wled->addr + PM8941_WLED_REG_SINK,
-				PM8941_WLED_REG_SINK_MASK, all);
+				wled->addr + WLED3_SINK_REG_CURR_SINK,
+				WLED3_SINK_REG_CURR_SINK_MASK, all);
 		if (rc)
 			return rc;
 	}
 
 	for (i = 0; i < wled->cfg.num_strings; ++i) {
-		u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
+		u16 addr = wled->addr + WLED3_SINK_REG_STR_OFFSET * i;
 
 		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
-				PM8941_WLED_REG_STR_MOD_MASK,
-				PM8941_WLED_REG_STR_MOD_EN);
+				addr + WLED3_SINK_REG_STR_MOD_EN_BASE,
+				WLED3_SINK_REG_STR_MOD_MASK,
+				WLED3_SINK_REG_STR_MOD_EN);
 		if (rc)
 			return rc;
 
 		if (wled->cfg.ext_gen) {
 			rc = regmap_update_bits(wled->regmap,
-					addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
-					PM8941_WLED_REG_STR_MOD_SRC_MASK,
-					PM8941_WLED_REG_STR_MOD_SRC_EXT);
+					addr + WLED3_SINK_REG_STR_MOD_SRC_BASE,
+					WLED3_SINK_REG_STR_MOD_SRC_MASK,
+					WLED3_SINK_REG_STR_MOD_SRC_EXT);
 			if (rc)
 				return rc;
 		}
 
 		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_SCALE_BASE,
-				PM8941_WLED_REG_STR_SCALE_MASK,
-				wled->cfg.i_limit);
+				addr + WLED3_SINK_REG_STR_FULL_SCALE_CURR,
+				WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK,
+				wled->cfg.string_i_limit);
 		if (rc)
 			return rc;
 
 		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_CABC_BASE,
-				PM8941_WLED_REG_STR_CABC_MASK,
+				addr + WLED3_SINK_REG_STR_CABC_BASE,
+				WLED3_SINK_REG_STR_CABC_MASK,
 				wled->cfg.cabc_en ?
-					PM8941_WLED_REG_STR_CABC_EN : 0);
+					WLED3_SINK_REG_STR_CABC_EN : 0);
 		if (rc)
 			return rc;
 	}
@@ -194,9 +196,9 @@ static int pm8941_wled_setup(struct pm8941_wled *wled)
 	return 0;
 }
 
-static const struct pm8941_wled_config pm8941_wled_config_defaults = {
-	.i_boost_limit = 3,
-	.i_limit = 20,
+static const struct wled_config wled3_config_defaults = {
+	.boost_i_limit = 3,
+	.string_i_limit = 20,
 	.ovp = 2,
 	.switch_freq = 5,
 	.num_strings = 0,
@@ -205,55 +207,55 @@ static int pm8941_wled_setup(struct pm8941_wled *wled)
 	.cabc_en = false,
 };
 
-struct pm8941_wled_var_cfg {
+struct wled_var_cfg {
 	const u32 *values;
 	u32 (*fn)(u32);
 	int size;
 };
 
-static const u32 pm8941_wled_i_boost_limit_values[] = {
+static const u32 wled3_boost_i_limit_values[] = {
 	105, 385, 525, 805, 980, 1260, 1400, 1680,
 };
 
-static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
-	.values = pm8941_wled_i_boost_limit_values,
-	.size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
+static const struct wled_var_cfg wled3_boost_i_limit_cfg = {
+	.values = wled3_boost_i_limit_values,
+	.size = ARRAY_SIZE(wled3_boost_i_limit_values),
 };
 
-static const u32 pm8941_wled_ovp_values[] = {
+static const u32 wled3_ovp_values[] = {
 	35, 32, 29, 27,
 };
 
-static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
-	.values = pm8941_wled_ovp_values,
-	.size = ARRAY_SIZE(pm8941_wled_ovp_values),
+static const struct wled_var_cfg wled3_ovp_cfg = {
+	.values = wled3_ovp_values,
+	.size = ARRAY_SIZE(wled3_ovp_values),
 };
 
-static u32 pm8941_wled_num_strings_values_fn(u32 idx)
+static u32 wled3_num_strings_values_fn(u32 idx)
 {
 	return idx + 1;
 }
 
-static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
-	.fn = pm8941_wled_num_strings_values_fn,
+static const struct wled_var_cfg wled3_num_strings_cfg = {
+	.fn = wled3_num_strings_values_fn,
 	.size = 3,
 };
 
-static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
+static u32 wled3_switch_freq_values_fn(u32 idx)
 {
 	return 19200 / (2 * (1 + idx));
 }
 
-static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
-	.fn = pm8941_wled_switch_freq_values_fn,
+static const struct wled_var_cfg wled3_switch_freq_cfg = {
+	.fn = wled3_switch_freq_values_fn,
 	.size = 16,
 };
 
-static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
+static const struct wled_var_cfg wled3_string_i_limit_cfg = {
 	.size = 26,
 };
 
-static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
+static u32 wled3_values(const struct wled_var_cfg *cfg, u32 idx)
 {
 	if (idx >= cfg->size)
 		return UINT_MAX;
@@ -264,9 +266,9 @@ static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
 	return idx;
 }
 
-static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
+static int wled_configure(struct wled *wled, struct device *dev)
 {
-	struct pm8941_wled_config *cfg = &wled->cfg;
+	struct wled_config *cfg = &wled->cfg;
 	u32 val;
 	int rc;
 	u32 c;
@@ -276,32 +278,32 @@ static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
 	const struct {
 		const char *name;
 		u32 *val_ptr;
-		const struct pm8941_wled_var_cfg *cfg;
+		const struct wled_var_cfg *cfg;
 	} u32_opts[] = {
 		{
 			"qcom,current-boost-limit",
-			&cfg->i_boost_limit,
-			.cfg = &pm8941_wled_i_boost_limit_cfg,
+			&cfg->boost_i_limit,
+			.cfg = &wled3_boost_i_limit_cfg,
 		},
 		{
 			"qcom,current-limit",
-			&cfg->i_limit,
-			.cfg = &pm8941_wled_i_limit_cfg,
+			&cfg->string_i_limit,
+			.cfg = &wled3_string_i_limit_cfg,
 		},
 		{
 			"qcom,ovp",
 			&cfg->ovp,
-			.cfg = &pm8941_wled_ovp_cfg,
+			.cfg = &wled3_ovp_cfg,
 		},
 		{
 			"qcom,switching-freq",
 			&cfg->switch_freq,
-			.cfg = &pm8941_wled_switch_freq_cfg,
+			.cfg = &wled3_switch_freq_cfg,
 		},
 		{
 			"qcom,num-strings",
 			&cfg->num_strings,
-			.cfg = &pm8941_wled_num_strings_cfg,
+			.cfg = &wled3_num_strings_cfg,
 		},
 	};
 	const struct {
@@ -324,7 +326,7 @@ static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
 	if (rc)
 		wled->name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn", dev->of_node);
 
-	*cfg = pm8941_wled_config_defaults;
+	*cfg = wled3_config_defaults;
 	for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
 		rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
 		if (rc = -EINVAL) {
@@ -336,7 +338,7 @@ static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
 
 		c = UINT_MAX;
 		for (j = 0; c != val; j++) {
-			c = pm8941_wled_values(u32_opts[i].cfg, j);
+			c = wled3_values(u32_opts[i].cfg, j);
 			if (c = UINT_MAX) {
 				dev_err(dev, "invalid value for '%s'\n",
 					u32_opts[i].name);
@@ -358,15 +360,15 @@ static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
 	return 0;
 }
 
-static const struct backlight_ops pm8941_wled_ops = {
-	.update_status = pm8941_wled_update_status,
+static const struct backlight_ops wled_ops = {
+	.update_status = wled_update_status,
 };
 
-static int pm8941_wled_probe(struct platform_device *pdev)
+static int wled_probe(struct platform_device *pdev)
 {
 	struct backlight_properties props;
 	struct backlight_device *bl;
-	struct pm8941_wled *wled;
+	struct wled *wled;
 	struct regmap *regmap;
 	u32 val;
 	int rc;
@@ -383,42 +385,42 @@ static int pm8941_wled_probe(struct platform_device *pdev)
 
 	wled->regmap = regmap;
 
-	rc = pm8941_wled_configure(wled, &pdev->dev);
+	rc = wled_configure(wled, &pdev->dev);
 	if (rc)
 		return rc;
 
-	rc = pm8941_wled_setup(wled);
+	rc = wled_setup(wled);
 	if (rc)
 		return rc;
 
-	val = PM8941_WLED_DEFAULT_BRIGHTNESS;
+	val = WLED_DEFAULT_BRIGHTNESS;
 	of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
 
 	memset(&props, 0, sizeof(struct backlight_properties));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = val;
-	props.max_brightness = PM8941_WLED_REG_VAL_MAX;
+	props.max_brightness = WLED3_SINK_REG_BRIGHT_MAX;
 	bl = devm_backlight_device_register(&pdev->dev, wled->name,
 					    &pdev->dev, wled,
-					    &pm8941_wled_ops, &props);
+					    &wled_ops, &props);
 	return PTR_ERR_OR_ZERO(bl);
 };
 
-static const struct of_device_id pm8941_wled_match_table[] = {
+static const struct of_device_id wled_match_table[] = {
 	{ .compatible = "qcom,pm8941-wled" },
 	{}
 };
-MODULE_DEVICE_TABLE(of, pm8941_wled_match_table);
+MODULE_DEVICE_TABLE(of, wled_match_table);
 
-static struct platform_driver pm8941_wled_driver = {
-	.probe = pm8941_wled_probe,
+static struct platform_driver wled_driver = {
+	.probe = wled_probe,
 	.driver	= {
-		.name = "pm8941-wled",
-		.of_match_table	= pm8941_wled_match_table,
+		.name = "qcom,wled",
+		.of_match_table	= wled_match_table,
 	},
 };
 
-module_platform_driver(pm8941_wled_driver);
+module_platform_driver(wled_driver);
 
-MODULE_DESCRIPTION("pm8941 wled driver");
+MODULE_DESCRIPTION("Qualcomm WLED driver");
 MODULE_LICENSE("GPL v2");
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project

[PATCH V6 5/8] backlight: qcom-wled: Restructure the driver for WLED3

[Kiran Gunda]

Restructure the driver to add the support for new WLED
peripherals.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
---
 drivers/video/backlight/qcom-wled.c | 395 ++++++++++++++++++++++--------------
 1 file changed, 245 insertions(+), 150 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index f191242..740f1b6 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -7,59 +7,71 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_address.h>
 #include <linux/regmap.h>
 
 /* From DT binding */
+#define WLED_MAX_STRINGS				4
+
 #define WLED_DEFAULT_BRIGHTNESS				2048
 
-#define WLED3_SINK_REG_BRIGHT_MAX			0xFFF
-#define WLED3_CTRL_REG_VAL_BASE				0x40
+#define WLED_SINK_REG_BRIGHT_MAX			0xFFF
 
-/* WLED3 control registers */
-#define WLED3_CTRL_REG_MOD_EN				0x46
-#define  WLED3_CTRL_REG_MOD_EN_BIT			BIT(7)
-#define  WLED3_CTRL_REG_MOD_EN_MASK			BIT(7)
+/* WLED control registers */
+#define WLED_CTRL_REG_MOD_EN				0x46
+#define  WLED_CTRL_REG_MOD_EN_MASK			BIT(7)
+#define  WLED_CTRL_REG_MOD_EN_SHIFT			7
 
-#define WLED3_CTRL_REG_FREQ				0x4c
-#define  WLED3_CTRL_REG_FREQ_MASK			0x0f
+#define WLED_CTRL_REG_FREQ				0x4c
+#define  WLED_CTRL_REG_FREQ_MASK			GENMASK(3, 0)
 
-#define WLED3_CTRL_REG_OVP				0x4d
-#define  WLED3_CTRL_REG_OVP_MASK			0x03
+#define WLED_CTRL_REG_OVP				0x4d
+#define  WLED_CTRL_REG_OVP_MASK				GENMASK(1, 0)
 
-#define WLED3_CTRL_REG_ILIMIT				0x4e
-#define  WLED3_CTRL_REG_ILIMIT_MASK			0x07
+#define WLED_CTRL_REG_ILIMIT				0x4e
+#define  WLED_CTRL_REG_ILIMIT_MASK			GENMASK(2, 0)
 
-/* WLED3 sink registers */
-#define WLED3_SINK_REG_SYNC				0x47
-#define  WLED3_SINK_REG_SYNC_MASK			0x07
-#define  WLED3_SINK_REG_SYNC_LED1			BIT(0)
-#define  WLED3_SINK_REG_SYNC_LED2			BIT(1)
-#define  WLED3_SINK_REG_SYNC_LED3			BIT(2)
-#define  WLED3_SINK_REG_SYNC_ALL			0x07
-#define  WLED3_SINK_REG_SYNC_CLEAR			0x00
+/* WLED sink registers */
+#define WLED_SINK_REG_SYNC				0x47
+#define  WLED_SINK_REG_SYNC_CLEAR			0x00
 
 #define WLED3_SINK_REG_CURR_SINK			0x4f
-#define  WLED3_SINK_REG_CURR_SINK_MASK			0xe0
-#define  WLED3_SINK_REG_CURR_SINK_SHFT			0x05
+#define  WLED3_SINK_REG_CURR_SINK_MASK			GENMASK(7, 5)
+#define  WLED3_SINK_REG_CURR_SINK_SHFT			5
 
-/* WLED3 per-'string' registers below */
-#define WLED3_SINK_REG_STR_OFFSET			0x10
+/* WLED3 specific per-'string' registers below */
+#define WLED3_SINK_REG_BRIGHT(n)			(0x40 + n)
 
-#define WLED3_SINK_REG_STR_MOD_EN_BASE			0x60
+#define WLED3_SINK_REG_STR_MOD_EN(n)			(0x60 + (n * 0x10))
 #define  WLED3_SINK_REG_STR_MOD_MASK			BIT(7)
-#define  WLED3_SINK_REG_STR_MOD_EN			BIT(7)
 
-#define WLED3_SINK_REG_STR_FULL_SCALE_CURR		0x62
-#define  WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK	0x1f
+#define WLED3_SINK_REG_STR_FULL_SCALE_CURR(n)		(0x62 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK	GENMASK(4, 0)
 
-#define WLED3_SINK_REG_STR_MOD_SRC_BASE			0x63
-#define  WLED3_SINK_REG_STR_MOD_SRC_MASK		0x01
+#define WLED3_SINK_REG_STR_MOD_SRC(n)			(0x63 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_MOD_SRC_MASK		BIT(0)
 #define  WLED3_SINK_REG_STR_MOD_SRC_INT			0x00
 #define  WLED3_SINK_REG_STR_MOD_SRC_EXT			0x01
 
-#define WLED3_SINK_REG_STR_CABC_BASE			0x66
+#define WLED3_SINK_REG_STR_CABC(n)			(0x66 + (n * 0x10))
 #define  WLED3_SINK_REG_STR_CABC_MASK			BIT(7)
-#define  WLED3_SINK_REG_STR_CABC_EN			BIT(7)
+
+struct wled_var_cfg {
+	const u32 *values;
+	u32 (*fn)(u32);
+	int size;
+};
+
+struct wled_u32_opts {
+	const char *name;
+	u32 *val_ptr;
+	const struct wled_var_cfg *cfg;
+};
+
+struct wled_bool_opts {
+	const char *name;
+	bool *val_ptr;
+};
 
 struct wled_config {
 	u32 boost_i_limit;
@@ -67,132 +79,179 @@ struct wled_config {
 	u32 switch_freq;
 	u32 num_strings;
 	u32 string_i_limit;
+	u32 enabled_strings[WLED_MAX_STRINGS];
 	bool cs_out_en;
 	bool ext_gen;
-	bool cabc_en;
+	bool cabc;
 };
 
 struct wled {
 	const char *name;
+	struct device *dev;
 	struct regmap *regmap;
-	u16 addr;
+	u16 ctrl_addr;
+	u16 max_string_count;
+	u32 brightness;
+	u32 max_brightness;
 
 	struct wled_config cfg;
+	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
 };
 
+static int wled3_set_brightness(struct wled *wled, u16 brightness)
+{
+	int rc, i;
+	u8 v[2];
+
+	v[0] = brightness & 0xff;
+	v[1] = (brightness >> 8) & 0xf;
+
+	for (i = 0;  i < wled->cfg.num_strings; ++i) {
+		rc = regmap_bulk_write(wled->regmap, wled->ctrl_addr +
+				       WLED3_SINK_REG_BRIGHT(i), v, 2);
+		if (rc < 0)
+			return rc;
+	}
+
+	return 0;
+}
+
+static int wled_module_enable(struct wled *wled, int val)
+{
+	int rc;
+
+	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+				WLED_CTRL_REG_MOD_EN,
+				WLED_CTRL_REG_MOD_EN_MASK,
+				val << WLED_CTRL_REG_MOD_EN_SHIFT);
+	return rc;
+}
+
+static int wled_sync_toggle(struct wled *wled)
+{
+	int rc;
+	unsigned int mask = GENMASK(wled->max_string_count - 1, 0);
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_SINK_REG_SYNC,
+				mask, mask);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_SINK_REG_SYNC,
+				mask, WLED_SINK_REG_SYNC_CLEAR);
+
+	return rc;
+}
+
 static int wled_update_status(struct backlight_device *bl)
 {
 	struct wled *wled = bl_get_data(bl);
-	u16 val = bl->props.brightness;
-	u8 ctrl = 0;
-	int rc;
-	int i;
+	u16 brightness = bl->props.brightness;
+	int rc = 0;
 
 	if (bl->props.power != FB_BLANK_UNBLANK ||
 	    bl->props.fb_blank != FB_BLANK_UNBLANK ||
 	    bl->props.state & BL_CORE_FBBLANK)
-		val = 0;
-
-	if (val != 0)
-		ctrl = WLED3_CTRL_REG_MOD_EN_BIT;
+		brightness = 0;
 
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_CTRL_REG_MOD_EN,
-			WLED3_CTRL_REG_MOD_EN_MASK, ctrl);
-	if (rc)
-		return rc;
+	if (brightness) {
+		rc = wled->wled_set_brightness(wled, brightness);
+		if (rc < 0) {
+			dev_err(wled->dev, "wled failed to set brightness rc:%d\n",
+				rc);
+			return rc;
+		}
 
-	for (i = 0; i < wled->cfg.num_strings; ++i) {
-		u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
+		rc = wled_sync_toggle(wled);
+		if (rc < 0) {
+			dev_err(wled->dev, "wled sync failed rc:%d\n", rc);
+			return rc;
+		}
+	}
 
-		rc = regmap_bulk_write(wled->regmap,
-				wled->addr + WLED3_CTRL_REG_VAL_BASE + 2 * i,
-				v, 2);
-		if (rc)
+	if (!!brightness != !!wled->brightness) {
+		rc = wled_module_enable(wled, !!brightness);
+		if (rc < 0) {
+			dev_err(wled->dev, "wled enable failed rc:%d\n", rc);
 			return rc;
+		}
 	}
 
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_SINK_REG_SYNC,
-			WLED3_SINK_REG_SYNC_MASK, WLED3_SINK_REG_SYNC_ALL);
-	if (rc)
-		return rc;
+	wled->brightness = brightness;
 
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_SINK_REG_SYNC,
-			WLED3_SINK_REG_SYNC_MASK, WLED3_SINK_REG_SYNC_CLEAR);
 	return rc;
 }
 
-static int wled_setup(struct wled *wled)
+static int wled3_setup(struct wled *wled)
 {
-	int rc;
-	int i;
+	u16 addr;
+	u8 sink_en = 0;
+	int rc, i, j;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_CTRL_REG_OVP,
-			WLED3_CTRL_REG_OVP_MASK, wled->cfg.ovp);
+				wled->ctrl_addr + WLED_CTRL_REG_OVP,
+				WLED_CTRL_REG_OVP_MASK, wled->cfg.ovp);
 	if (rc)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_CTRL_REG_ILIMIT,
-			WLED3_CTRL_REG_ILIMIT_MASK, wled->cfg.boost_i_limit);
+				wled->ctrl_addr + WLED_CTRL_REG_ILIMIT,
+				WLED_CTRL_REG_ILIMIT_MASK,
+				wled->cfg.boost_i_limit);
 	if (rc)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-			wled->addr + WLED3_CTRL_REG_FREQ,
-			WLED3_CTRL_REG_FREQ_MASK, wled->cfg.switch_freq);
+				wled->ctrl_addr + WLED_CTRL_REG_FREQ,
+				WLED_CTRL_REG_FREQ_MASK,
+				wled->cfg.switch_freq);
 	if (rc)
 		return rc;
 
-	if (wled->cfg.cs_out_en) {
-		u8 all = (BIT(wled->cfg.num_strings) - 1)
-				<< WLED3_SINK_REG_CURR_SINK_SHFT;
-
-		rc = regmap_update_bits(wled->regmap,
-				wled->addr + WLED3_SINK_REG_CURR_SINK,
-				WLED3_SINK_REG_CURR_SINK_MASK, all);
-		if (rc)
-			return rc;
-	}
-
 	for (i = 0; i < wled->cfg.num_strings; ++i) {
-		u16 addr = wled->addr + WLED3_SINK_REG_STR_OFFSET * i;
-
-		rc = regmap_update_bits(wled->regmap,
-				addr + WLED3_SINK_REG_STR_MOD_EN_BASE,
-				WLED3_SINK_REG_STR_MOD_MASK,
-				WLED3_SINK_REG_STR_MOD_EN);
+		j = wled->cfg.enabled_strings[i];
+		addr = wled->ctrl_addr + WLED3_SINK_REG_STR_MOD_EN(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED3_SINK_REG_STR_MOD_MASK,
+					WLED3_SINK_REG_STR_MOD_MASK);
 		if (rc)
 			return rc;
 
 		if (wled->cfg.ext_gen) {
-			rc = regmap_update_bits(wled->regmap,
-					addr + WLED3_SINK_REG_STR_MOD_SRC_BASE,
-					WLED3_SINK_REG_STR_MOD_SRC_MASK,
-					WLED3_SINK_REG_STR_MOD_SRC_EXT);
+			addr = wled->ctrl_addr + WLED3_SINK_REG_STR_MOD_SRC(j);
+			rc = regmap_update_bits(wled->regmap, addr,
+						WLED3_SINK_REG_STR_MOD_SRC_MASK,
+						WLED3_SINK_REG_STR_MOD_SRC_EXT);
 			if (rc)
 				return rc;
 		}
 
-		rc = regmap_update_bits(wled->regmap,
-				addr + WLED3_SINK_REG_STR_FULL_SCALE_CURR,
-				WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK,
-				wled->cfg.string_i_limit);
+		addr = wled->ctrl_addr + WLED3_SINK_REG_STR_FULL_SCALE_CURR(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK,
+					wled->cfg.string_i_limit);
 		if (rc)
 			return rc;
 
-		rc = regmap_update_bits(wled->regmap,
-				addr + WLED3_SINK_REG_STR_CABC_BASE,
-				WLED3_SINK_REG_STR_CABC_MASK,
-				wled->cfg.cabc_en ?
-					WLED3_SINK_REG_STR_CABC_EN : 0);
+		addr = wled->ctrl_addr + WLED3_SINK_REG_STR_CABC(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED3_SINK_REG_STR_CABC_MASK,
+					wled->cfg.cabc ?
+					WLED3_SINK_REG_STR_CABC_MASK : 0);
 		if (rc)
 			return rc;
+
+		sink_en |= BIT(j + WLED3_SINK_REG_CURR_SINK_SHFT);
 	}
 
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED3_SINK_REG_CURR_SINK,
+				WLED3_SINK_REG_CURR_SINK_MASK, sink_en);
+	if (rc)
+		return rc;
+
 	return 0;
 }
 
@@ -200,17 +259,12 @@ static int wled_setup(struct wled *wled)
 	.boost_i_limit = 3,
 	.string_i_limit = 20,
 	.ovp = 2,
+	.num_strings = 3,
 	.switch_freq = 5,
-	.num_strings = 0,
 	.cs_out_en = false,
 	.ext_gen = false,
-	.cabc_en = false,
-};
-
-struct wled_var_cfg {
-	const u32 *values;
-	u32 (*fn)(u32);
-	int size;
+	.cabc = false,
+	.enabled_strings = {0, 1, 2, 3},
 };
 
 static const u32 wled3_boost_i_limit_values[] = {
@@ -255,7 +309,11 @@ static u32 wled3_switch_freq_values_fn(u32 idx)
 	.size = 26,
 };
 
-static u32 wled3_values(const struct wled_var_cfg *cfg, u32 idx)
+static const struct wled_var_cfg wled3_string_cfg = {
+	.size = 8,
+};
+
+static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
 {
 	if (idx >= cfg->size)
 		return UINT_MAX;
@@ -266,68 +324,75 @@ static u32 wled3_values(const struct wled_var_cfg *cfg, u32 idx)
 	return idx;
 }
 
-static int wled_configure(struct wled *wled, struct device *dev)
+static int wled_configure(struct wled *wled, int version)
 {
 	struct wled_config *cfg = &wled->cfg;
-	u32 val;
-	int rc;
-	u32 c;
-	int i;
-	int j;
-
-	const struct {
-		const char *name;
-		u32 *val_ptr;
-		const struct wled_var_cfg *cfg;
-	} u32_opts[] = {
+	struct device *dev = wled->dev;
+	const __be32 *prop_addr;
+	u32 size, val, c, string_len;
+	int rc, i, j;
+
+	const struct wled_u32_opts *u32_opts = NULL;
+	const struct wled_u32_opts wled3_opts[] = {
 		{
-			"qcom,current-boost-limit",
-			&cfg->boost_i_limit,
+			.name = "qcom,current-boost-limit",
+			.val_ptr = &cfg->boost_i_limit,
 			.cfg = &wled3_boost_i_limit_cfg,
 		},
 		{
-			"qcom,current-limit",
-			&cfg->string_i_limit,
+			.name = "qcom,current-limit",
+			.val_ptr = &cfg->string_i_limit,
 			.cfg = &wled3_string_i_limit_cfg,
 		},
 		{
-			"qcom,ovp",
-			&cfg->ovp,
+			.name = "qcom,ovp",
+			.val_ptr = &cfg->ovp,
 			.cfg = &wled3_ovp_cfg,
 		},
 		{
-			"qcom,switching-freq",
-			&cfg->switch_freq,
+			.name = "qcom,switching-freq",
+			.val_ptr = &cfg->switch_freq,
 			.cfg = &wled3_switch_freq_cfg,
 		},
 		{
-			"qcom,num-strings",
-			&cfg->num_strings,
+			.name = "qcom,num-strings",
+			.val_ptr = &cfg->num_strings,
 			.cfg = &wled3_num_strings_cfg,
 		},
 	};
-	const struct {
-		const char *name;
-		bool *val_ptr;
-	} bool_opts[] = {
+
+	const struct wled_bool_opts bool_opts[] = {
 		{ "qcom,cs-out", &cfg->cs_out_en, },
 		{ "qcom,ext-gen", &cfg->ext_gen, },
-		{ "qcom,cabc", &cfg->cabc_en, },
+		{ "qcom,cabc", &cfg->cabc, },
 	};
 
-	rc = of_property_read_u32(dev->of_node, "reg", &val);
-	if (rc || val > 0xffff) {
-		dev_err(dev, "invalid IO resources\n");
-		return rc ? rc : -EINVAL;
+	prop_addr = of_get_address(dev->of_node, 0, NULL, NULL);
+	if (!prop_addr) {
+		dev_err(wled->dev, "invalid IO resources\n");
+		return -EINVAL;
 	}
-	wled->addr = val;
+	wled->ctrl_addr = be32_to_cpu(*prop_addr);
 
 	rc = of_property_read_string(dev->of_node, "label", &wled->name);
 	if (rc)
 		wled->name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn", dev->of_node);
 
-	*cfg = wled3_config_defaults;
-	for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
+	switch (version) {
+	case 3:
+		u32_opts = wled3_opts;
+		size = ARRAY_SIZE(wled3_opts);
+		*cfg = wled3_config_defaults;
+		wled->wled_set_brightness = wled3_set_brightness;
+		wled->max_string_count = 3;
+		break;
+
+	default:
+		dev_err(wled->dev, "Invalid WLED version\n");
+		break;
+	}
+
+	for (i = 0; i < size; ++i) {
 		rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
 		if (rc = -EINVAL) {
 			continue;
@@ -338,12 +403,15 @@ static int wled_configure(struct wled *wled, struct device *dev)
 
 		c = UINT_MAX;
 		for (j = 0; c != val; j++) {
-			c = wled3_values(u32_opts[i].cfg, j);
+			c = wled_values(u32_opts[i].cfg, j);
 			if (c = UINT_MAX) {
 				dev_err(dev, "invalid value for '%s'\n",
 					u32_opts[i].name);
 				return -EINVAL;
 			}
+
+			if (c = val)
+				break;
 		}
 
 		dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, c);
@@ -357,6 +425,15 @@ static int wled_configure(struct wled *wled, struct device *dev)
 
 	cfg->num_strings = cfg->num_strings + 1;
 
+	string_len = of_property_count_elems_of_size(dev->of_node,
+						     "qcom,enabled-strings",
+						     sizeof(u32));
+	if (string_len > 0)
+		rc = of_property_read_u32_array(dev->of_node,
+						"qcom,enabled-strings",
+						wled->cfg.enabled_strings,
+						sizeof(u32));
+
 	return 0;
 }
 
@@ -370,6 +447,7 @@ static int wled_probe(struct platform_device *pdev)
 	struct backlight_device *bl;
 	struct wled *wled;
 	struct regmap *regmap;
+	int version;
 	u32 val;
 	int rc;
 
@@ -384,22 +462,39 @@ static int wled_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	wled->regmap = regmap;
+	wled->dev = &pdev->dev;
 
-	rc = wled_configure(wled, &pdev->dev);
-	if (rc)
-		return rc;
+	version = (uintptr_t)of_device_get_match_data(&pdev->dev);
+	if (!version) {
+		dev_err(&pdev->dev, "Unknown device version\n");
+		return -ENODEV;
+	}
 
-	rc = wled_setup(wled);
+	rc = wled_configure(wled, version);
 	if (rc)
 		return rc;
 
+	switch (version) {
+	case 3:
+		rc = wled3_setup(wled);
+		if (rc) {
+			dev_err(&pdev->dev, "wled3_setup failed\n");
+			return rc;
+		}
+		break;
+
+	default:
+		dev_err(wled->dev, "Invalid WLED version\n");
+		break;
+	}
+
 	val = WLED_DEFAULT_BRIGHTNESS;
 	of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
 
 	memset(&props, 0, sizeof(struct backlight_properties));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = val;
-	props.max_brightness = WLED3_SINK_REG_BRIGHT_MAX;
+	props.max_brightness = WLED_SINK_REG_BRIGHT_MAX;
 	bl = devm_backlight_device_register(&pdev->dev, wled->name,
 					    &pdev->dev, wled,
 					    &wled_ops, &props);
@@ -407,7 +502,7 @@ static int wled_probe(struct platform_device *pdev)
 };
 
 static const struct of_device_id wled_match_table[] = {
-	{ .compatible = "qcom,pm8941-wled" },
+	{ .compatible = "qcom,pm8941-wled", .data = (void *)3 },
 	{}
 };
 MODULE_DEVICE_TABLE(of, wled_match_table);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project

Re: [PATCH V6 5/8] backlight: qcom-wled: Restructure the driver for WLED3

[Dan Murphy]

Kiran

On 9/30/19 1:39 AM, Kiran Gunda wrote:
> Restructure the driver to add the support for new WLED
> peripherals.
>
> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
> ---
>   drivers/video/backlight/qcom-wled.c | 395 ++++++++++++++++++++++--------------
>   1 file changed, 245 insertions(+), 150 deletions(-)
>
> diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
> index f191242..740f1b6 100644
> --- a/drivers/video/backlight/qcom-wled.c
> +++ b/drivers/video/backlight/qcom-wled.c
> @@ -7,59 +7,71 @@
>   #include <linux/module.h>
>   #include <linux/of.h>
>   #include <linux/of_device.h>
> +#include <linux/of_address.h>
>   #include <linux/regmap.h>
>   
>   /* From DT binding */
> +#define WLED_MAX_STRINGS				4
> +
>   #define WLED_DEFAULT_BRIGHTNESS				2048
>   
> -#define WLED3_SINK_REG_BRIGHT_MAX			0xFFF
> -#define WLED3_CTRL_REG_VAL_BASE				0x40
> +#define WLED_SINK_REG_BRIGHT_MAX			0xFFF

Why did you change some of these again?

Can you just change it to the final #define in patch 4/8?

Dan

<snip>

Re: [PATCH V6 5/8] backlight: qcom-wled: Restructure the driver for WLED3

[kgunda]

On 2019-10-01 20:47, Dan Murphy wrote:
> Kiran
> 
> On 9/30/19 1:39 AM, Kiran Gunda wrote:
>> Restructure the driver to add the support for new WLED
>> peripherals.
>> 
>> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
>> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
>> ---
>>   drivers/video/backlight/qcom-wled.c | 395 
>> ++++++++++++++++++++++--------------
>>   1 file changed, 245 insertions(+), 150 deletions(-)
>> 
>> diff --git a/drivers/video/backlight/qcom-wled.c 
>> b/drivers/video/backlight/qcom-wled.c
>> index f191242..740f1b6 100644
>> --- a/drivers/video/backlight/qcom-wled.c
>> +++ b/drivers/video/backlight/qcom-wled.c
>> @@ -7,59 +7,71 @@
>>   #include <linux/module.h>
>>   #include <linux/of.h>
>>   #include <linux/of_device.h>
>> +#include <linux/of_address.h>
>>   #include <linux/regmap.h>
>>     /* From DT binding */
>> +#define WLED_MAX_STRINGS				4
>> +
>>   #define WLED_DEFAULT_BRIGHTNESS				2048
>>   -#define WLED3_SINK_REG_BRIGHT_MAX			0xFFF
>> -#define WLED3_CTRL_REG_VAL_BASE				0x40
>> +#define WLED_SINK_REG_BRIGHT_MAX			0xFFF
> 
> Why did you change some of these again?
> 
> Can you just change it to the final #define in patch 4/8?
> 
> Dan
> 
> <snip>
Ok.. Looks like some thing went wrong with this series. I will re-upload 
it again.

[PATCH V6 6/8] backlight: qcom-wled: Add support for WLED4 peripheral

[Kiran Gunda]

WLED4 peripheral is present on some PMICs like pmi8998 and
pm660l. It has a different register map and configurations
are also different. Add support for it.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---
 drivers/video/backlight/qcom-wled.c | 263 +++++++++++++++++++++++++++++++++++-
 1 file changed, 257 insertions(+), 6 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 740f1b6..b012a2a 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -56,6 +56,28 @@
 #define WLED3_SINK_REG_STR_CABC(n)			(0x66 + (n * 0x10))
 #define  WLED3_SINK_REG_STR_CABC_MASK			BIT(7)
 
+/* WLED4 specific sink registers */
+#define WLED4_SINK_REG_CURR_SINK			0x46
+#define  WLED4_SINK_REG_CURR_SINK_MASK			GENMASK(7, 4)
+#define  WLED4_SINK_REG_CURR_SINK_SHFT			4
+
+/* WLED4 specific per-'string' registers below */
+#define WLED4_SINK_REG_STR_MOD_EN(n)			(0x50 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_MOD_MASK			BIT(7)
+
+#define WLED4_SINK_REG_STR_FULL_SCALE_CURR(n)		(0x52 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_FULL_SCALE_CURR_MASK	GENMASK(3, 0)
+
+#define WLED4_SINK_REG_STR_MOD_SRC(n)			(0x53 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_MOD_SRC_MASK		BIT(0)
+#define  WLED4_SINK_REG_STR_MOD_SRC_INT			0x00
+#define  WLED4_SINK_REG_STR_MOD_SRC_EXT			0x01
+
+#define WLED4_SINK_REG_STR_CABC(n)			(0x56 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_CABC_MASK			BIT(7)
+
+#define WLED4_SINK_REG_BRIGHT(n)			(0x57 + (n * 0x10))
+
 struct wled_var_cfg {
 	const u32 *values;
 	u32 (*fn)(u32);
@@ -90,6 +112,7 @@ struct wled {
 	struct device *dev;
 	struct regmap *regmap;
 	u16 ctrl_addr;
+	u16 sink_addr;
 	u16 max_string_count;
 	u32 brightness;
 	u32 max_brightness;
@@ -116,6 +139,29 @@ static int wled3_set_brightness(struct wled *wled, u16 brightness)
 	return 0;
 }
 
+static int wled4_set_brightness(struct wled *wled, u16 brightness)
+{
+	int rc, i;
+	u16 low_limit = wled->max_brightness * 4 / 1000;
+	u8 v[2];
+
+	/* WLED4's lower limit of operation is 0.4% */
+	if (brightness > 0 && brightness < low_limit)
+		brightness = low_limit;
+
+	v[0] = brightness & 0xff;
+	v[1] = (brightness >> 8) & 0xf;
+
+	for (i = 0;  i < wled->cfg.num_strings; ++i) {
+		rc = regmap_bulk_write(wled->regmap, wled->sink_addr +
+				       WLED4_SINK_REG_BRIGHT(i), v, 2);
+		if (rc < 0)
+			return rc;
+	}
+
+	return 0;
+}
+
 static int wled_module_enable(struct wled *wled, int val)
 {
 	int rc;
@@ -133,13 +179,13 @@ static int wled_sync_toggle(struct wled *wled)
 	unsigned int mask = GENMASK(wled->max_string_count - 1, 0);
 
 	rc = regmap_update_bits(wled->regmap,
-				wled->ctrl_addr + WLED_SINK_REG_SYNC,
+				wled->sink_addr + WLED_SINK_REG_SYNC,
 				mask, mask);
 	if (rc < 0)
 		return rc;
 
 	rc = regmap_update_bits(wled->regmap,
-				wled->ctrl_addr + WLED_SINK_REG_SYNC,
+				wled->sink_addr + WLED_SINK_REG_SYNC,
 				mask, WLED_SINK_REG_SYNC_CLEAR);
 
 	return rc;
@@ -267,6 +313,120 @@ static int wled3_setup(struct wled *wled)
 	.enabled_strings = {0, 1, 2, 3},
 };
 
+static int wled4_setup(struct wled *wled)
+{
+	int rc, temp, i, j;
+	u16 addr;
+	u8 sink_en = 0;
+	u32 sink_cfg = 0;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_CTRL_REG_OVP,
+				WLED_CTRL_REG_OVP_MASK, wled->cfg.ovp);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_CTRL_REG_ILIMIT,
+				WLED_CTRL_REG_ILIMIT_MASK,
+				wled->cfg.boost_i_limit);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_CTRL_REG_FREQ,
+				WLED_CTRL_REG_FREQ_MASK,
+				wled->cfg.switch_freq);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_read(wled->regmap, wled->sink_addr +
+			 WLED4_SINK_REG_CURR_SINK, &sink_cfg);
+	if (rc < 0)
+		return rc;
+
+	for (i = 0; i < wled->cfg.num_strings; i++) {
+		j = wled->cfg.enabled_strings[i];
+		temp = j + WLED4_SINK_REG_CURR_SINK_SHFT;
+		sink_en |= 1 << temp;
+	}
+
+	if (sink_cfg = sink_en)
+		return 0;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
+				WLED4_SINK_REG_CURR_SINK_MASK, 0);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+				WLED_CTRL_REG_MOD_EN,
+				WLED_CTRL_REG_MOD_EN_MASK, 0);
+	if (rc < 0)
+		return rc;
+
+	/* Per sink/string configuration */
+	for (i = 0; i < wled->cfg.num_strings; i++) {
+		j = wled->cfg.enabled_strings[i];
+
+		addr = wled->sink_addr +
+				WLED4_SINK_REG_STR_MOD_EN(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED4_SINK_REG_STR_MOD_MASK,
+					WLED4_SINK_REG_STR_MOD_MASK);
+		if (rc < 0)
+			return rc;
+
+		addr = wled->sink_addr +
+				WLED4_SINK_REG_STR_FULL_SCALE_CURR(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED4_SINK_REG_STR_FULL_SCALE_CURR_MASK,
+					wled->cfg.string_i_limit);
+		if (rc < 0)
+			return rc;
+
+		addr = wled->sink_addr +
+				WLED4_SINK_REG_STR_CABC(j);
+		rc = regmap_update_bits(wled->regmap, addr,
+					WLED4_SINK_REG_STR_CABC_MASK,
+					wled->cfg.cabc ?
+					WLED4_SINK_REG_STR_CABC_MASK : 0);
+		if (rc < 0)
+			return rc;
+	}
+
+	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+				WLED_CTRL_REG_MOD_EN,
+				WLED_CTRL_REG_MOD_EN_MASK,
+				WLED_CTRL_REG_MOD_EN_MASK);
+	if (rc < 0)
+		return rc;
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
+				WLED4_SINK_REG_CURR_SINK_MASK, sink_en);
+	if (rc < 0)
+		return rc;
+
+	rc = wled_sync_toggle(wled);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to toggle sync reg rc:%d\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+static const struct wled_config wled4_config_defaults = {
+	.boost_i_limit = 4,
+	.string_i_limit = 10,
+	.ovp = 1,
+	.num_strings = 4,
+	.switch_freq = 11,
+	.cabc = false,
+};
+
 static const u32 wled3_boost_i_limit_values[] = {
 	105, 385, 525, 805, 980, 1260, 1400, 1680,
 };
@@ -276,6 +436,15 @@ static int wled3_setup(struct wled *wled)
 	.size = ARRAY_SIZE(wled3_boost_i_limit_values),
 };
 
+static const u32 wled4_boost_i_limit_values[] = {
+	105, 280, 450, 620, 970, 1150, 1300, 1500,
+};
+
+static const struct wled_var_cfg wled4_boost_i_limit_cfg = {
+	.values = wled4_boost_i_limit_values,
+	.size = ARRAY_SIZE(wled4_boost_i_limit_values),
+};
+
 static const u32 wled3_ovp_values[] = {
 	35, 32, 29, 27,
 };
@@ -285,6 +454,15 @@ static int wled3_setup(struct wled *wled)
 	.size = ARRAY_SIZE(wled3_ovp_values),
 };
 
+static const u32 wled4_ovp_values[] = {
+	31100, 29600, 19600, 18100,
+};
+
+static const struct wled_var_cfg wled4_ovp_cfg = {
+	.values = wled4_ovp_values,
+	.size = ARRAY_SIZE(wled4_ovp_values),
+};
+
 static u32 wled3_num_strings_values_fn(u32 idx)
 {
 	return idx + 1;
@@ -295,6 +473,11 @@ static u32 wled3_num_strings_values_fn(u32 idx)
 	.size = 3,
 };
 
+static const struct wled_var_cfg wled4_num_strings_cfg = {
+	.fn = wled3_num_strings_values_fn,
+	.size = 4,
+};
+
 static u32 wled3_switch_freq_values_fn(u32 idx)
 {
 	return 19200 / (2 * (1 + idx));
@@ -309,10 +492,24 @@ static u32 wled3_switch_freq_values_fn(u32 idx)
 	.size = 26,
 };
 
+static const u32 wled4_string_i_limit_values[] = {
+	0, 2500, 5000, 7500, 10000, 12500, 15000, 17500, 20000,
+	22500, 25000, 27500, 30000,
+};
+
+static const struct wled_var_cfg wled4_string_i_limit_cfg = {
+	.values = wled4_string_i_limit_values,
+	.size = ARRAY_SIZE(wled4_string_i_limit_values),
+};
+
 static const struct wled_var_cfg wled3_string_cfg = {
 	.size = 8,
 };
 
+static const struct wled_var_cfg wled4_string_cfg = {
+	.size = 16,
+};
+
 static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
 {
 	if (idx >= cfg->size)
@@ -361,6 +558,34 @@ static int wled_configure(struct wled *wled, int version)
 		},
 	};
 
+	const struct wled_u32_opts wled4_opts[] = {
+		{
+			.name = "qcom,current-boost-limit",
+			.val_ptr = &cfg->boost_i_limit,
+			.cfg = &wled4_boost_i_limit_cfg,
+		},
+		{
+			.name = "qcom,current-limit-microamp",
+			.val_ptr = &cfg->string_i_limit,
+			.cfg = &wled4_string_i_limit_cfg,
+		},
+		{
+			.name = "qcom,ovp-millivolt",
+			.val_ptr = &cfg->ovp,
+			.cfg = &wled4_ovp_cfg,
+		},
+		{
+			.name = "qcom,switching-freq",
+			.val_ptr = &cfg->switch_freq,
+			.cfg = &wled3_switch_freq_cfg,
+		},
+		{
+			.name = "qcom,num-strings",
+			.val_ptr = &cfg->num_strings,
+			.cfg = &wled4_num_strings_cfg,
+		},
+	};
+
 	const struct wled_bool_opts bool_opts[] = {
 		{ "qcom,cs-out", &cfg->cs_out_en, },
 		{ "qcom,ext-gen", &cfg->ext_gen, },
@@ -374,10 +599,6 @@ static int wled_configure(struct wled *wled, int version)
 	}
 	wled->ctrl_addr = be32_to_cpu(*prop_addr);
 
-	rc = of_property_read_string(dev->of_node, "label", &wled->name);
-	if (rc)
-		wled->name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn", dev->of_node);
-
 	switch (version) {
 	case 3:
 		u32_opts = wled3_opts;
@@ -385,6 +606,22 @@ static int wled_configure(struct wled *wled, int version)
 		*cfg = wled3_config_defaults;
 		wled->wled_set_brightness = wled3_set_brightness;
 		wled->max_string_count = 3;
+		wled->sink_addr = wled->ctrl_addr;
+		break;
+
+	case 4:
+		u32_opts = wled4_opts;
+		size = ARRAY_SIZE(wled4_opts);
+		*cfg = wled4_config_defaults;
+		wled->wled_set_brightness = wled4_set_brightness;
+		wled->max_string_count = 4;
+
+		prop_addr = of_get_address(dev->of_node, 1, NULL, NULL);
+		if (!prop_addr) {
+			dev_err(wled->dev, "invalid IO resources\n");
+			return -EINVAL;
+		}
+		wled->sink_addr = be32_to_cpu(*prop_addr);
 		break;
 
 	default:
@@ -392,6 +629,10 @@ static int wled_configure(struct wled *wled, int version)
 		break;
 	}
 
+	rc = of_property_read_string(dev->of_node, "label", &wled->name);
+	if (rc)
+		wled->name = dev->of_node->name;
+
 	for (i = 0; i < size; ++i) {
 		rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
 		if (rc = -EINVAL) {
@@ -483,6 +724,14 @@ static int wled_probe(struct platform_device *pdev)
 		}
 		break;
 
+	case 4:
+		rc = wled4_setup(wled);
+		if (rc) {
+			dev_err(&pdev->dev, "wled4_setup failed\n");
+			return rc;
+		}
+		break;
+
 	default:
 		dev_err(wled->dev, "Invalid WLED version\n");
 		break;
@@ -503,6 +752,8 @@ static int wled_probe(struct platform_device *pdev)
 
 static const struct of_device_id wled_match_table[] = {
 	{ .compatible = "qcom,pm8941-wled", .data = (void *)3 },
+	{ .compatible = "qcom,pmi8998-wled", .data = (void *)4 },
+	{ .compatible = "qcom,pm660l-wled", .data = (void *)4 },
 	{}
 };
 MODULE_DEVICE_TABLE(of, wled_match_table);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project

[PATCH V6 7/8] backlight: qcom-wled: add support for short circuit handling.

[Kiran Gunda]

Handle the short circuit interrupt and check if the short circuit
interrupt is valid. Re-enable the module to check if it goes
away. Disable the module altogether if the short circuit event
persists.

Change-Id: Ia3f5272e1a50927467611bef4a0d2218dbeb95e6
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---
 drivers/video/backlight/qcom-wled.c | 132 ++++++++++++++++++++++++++++++++++--
 1 file changed, 128 insertions(+), 4 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index b012a2a..556c734 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -2,6 +2,9 @@
 /* Copyright (c) 2015, Sony Mobile Communications, AB.
  */
 
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/ktime.h>
 #include <linux/kernel.h>
 #include <linux/backlight.h>
 #include <linux/module.h>
@@ -56,6 +59,16 @@
 #define WLED3_SINK_REG_STR_CABC(n)			(0x66 + (n * 0x10))
 #define  WLED3_SINK_REG_STR_CABC_MASK			BIT(7)
 
+/* WLED4 specific control registers */
+#define WLED4_CTRL_REG_SHORT_PROTECT			0x5e
+#define  WLED4_CTRL_REG_SHORT_EN_MASK			BIT(7)
+
+#define WLED4_CTRL_REG_SEC_ACCESS			0xd0
+#define  WLED4_CTRL_REG_SEC_UNLOCK			0xa5
+
+#define WLED4_CTRL_REG_TEST1				0xe2
+#define  WLED4_CTRL_REG_TEST1_EXT_FET_DTEST2		0x09
+
 /* WLED4 specific sink registers */
 #define WLED4_SINK_REG_CURR_SINK			0x46
 #define  WLED4_SINK_REG_CURR_SINK_MASK			GENMASK(7, 4)
@@ -105,17 +118,23 @@ struct wled_config {
 	bool cs_out_en;
 	bool ext_gen;
 	bool cabc;
+	bool external_pfet;
 };
 
 struct wled {
 	const char *name;
 	struct device *dev;
 	struct regmap *regmap;
+	struct mutex lock;	/* Lock to avoid race from thread irq handler */
+	ktime_t last_short_event;
 	u16 ctrl_addr;
 	u16 sink_addr;
 	u16 max_string_count;
 	u32 brightness;
 	u32 max_brightness;
+	u32 short_count;
+	bool disabled_by_short;
+	bool has_short_detect;
 
 	struct wled_config cfg;
 	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
@@ -166,6 +185,9 @@ static int wled_module_enable(struct wled *wled, int val)
 {
 	int rc;
 
+	if (wled->disabled_by_short)
+		return -ENXIO;
+
 	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
 				WLED_CTRL_REG_MOD_EN,
 				WLED_CTRL_REG_MOD_EN_MASK,
@@ -202,18 +224,19 @@ static int wled_update_status(struct backlight_device *bl)
 	    bl->props.state & BL_CORE_FBBLANK)
 		brightness = 0;
 
+	mutex_lock(&wled->lock);
 	if (brightness) {
 		rc = wled->wled_set_brightness(wled, brightness);
 		if (rc < 0) {
 			dev_err(wled->dev, "wled failed to set brightness rc:%d\n",
 				rc);
-			return rc;
+			goto unlock_mutex;
 		}
 
 		rc = wled_sync_toggle(wled);
 		if (rc < 0) {
 			dev_err(wled->dev, "wled sync failed rc:%d\n", rc);
-			return rc;
+			goto unlock_mutex;
 		}
 	}
 
@@ -221,15 +244,61 @@ static int wled_update_status(struct backlight_device *bl)
 		rc = wled_module_enable(wled, !!brightness);
 		if (rc < 0) {
 			dev_err(wled->dev, "wled enable failed rc:%d\n", rc);
-			return rc;
+			goto unlock_mutex;
 		}
 	}
 
 	wled->brightness = brightness;
 
+unlock_mutex:
+	mutex_unlock(&wled->lock);
+
 	return rc;
 }
 
+#define WLED_SHORT_DLY_MS			20
+#define WLED_SHORT_CNT_MAX			5
+#define WLED_SHORT_RESET_CNT_DLY_US		USEC_PER_SEC
+
+static irqreturn_t wled_short_irq_handler(int irq, void *_wled)
+{
+	struct wled *wled = _wled;
+	int rc;
+	s64 elapsed_time;
+
+	wled->short_count++;
+	mutex_lock(&wled->lock);
+	rc = wled_module_enable(wled, false);
+	if (rc < 0) {
+		dev_err(wled->dev, "wled disable failed rc:%d\n", rc);
+		goto unlock_mutex;
+	}
+
+	elapsed_time = ktime_us_delta(ktime_get(),
+				      wled->last_short_event);
+	if (elapsed_time > WLED_SHORT_RESET_CNT_DLY_US)
+		wled->short_count = 1;
+
+	if (wled->short_count > WLED_SHORT_CNT_MAX) {
+		dev_err(wled->dev, "Short trigged %d times, disabling WLED forever!\n",
+			wled->short_count);
+		wled->disabled_by_short = true;
+		goto unlock_mutex;
+	}
+
+	wled->last_short_event = ktime_get();
+
+	msleep(WLED_SHORT_DLY_MS);
+	rc = wled_module_enable(wled, true);
+	if (rc < 0)
+		dev_err(wled->dev, "wled enable failed rc:%d\n", rc);
+
+unlock_mutex:
+	mutex_unlock(&wled->lock);
+
+	return IRQ_HANDLED;
+}
+
 static int wled3_setup(struct wled *wled)
 {
 	u16 addr;
@@ -318,7 +387,7 @@ static int wled4_setup(struct wled *wled)
 	int rc, temp, i, j;
 	u16 addr;
 	u8 sink_en = 0;
-	u32 sink_cfg = 0;
+	u32 sink_cfg;
 
 	rc = regmap_update_bits(wled->regmap,
 				wled->ctrl_addr + WLED_CTRL_REG_OVP,
@@ -340,6 +409,21 @@ static int wled4_setup(struct wled *wled)
 	if (rc < 0)
 		return rc;
 
+	if (wled->cfg.external_pfet) {
+		/* Unlock the secure register access */
+		rc = regmap_write(wled->regmap, wled->ctrl_addr +
+				  WLED4_CTRL_REG_SEC_ACCESS,
+				  WLED4_CTRL_REG_SEC_UNLOCK);
+		if (rc < 0)
+			return rc;
+
+		rc = regmap_write(wled->regmap,
+				  wled->ctrl_addr + WLED4_CTRL_REG_TEST1,
+				  WLED4_CTRL_REG_TEST1_EXT_FET_DTEST2);
+		if (rc < 0)
+			return rc;
+	}
+
 	rc = regmap_read(wled->regmap, wled->sink_addr +
 			 WLED4_SINK_REG_CURR_SINK, &sink_cfg);
 	if (rc < 0)
@@ -425,6 +509,7 @@ static int wled4_setup(struct wled *wled)
 	.num_strings = 4,
 	.switch_freq = 11,
 	.cabc = false,
+	.external_pfet = false,
 };
 
 static const u32 wled3_boost_i_limit_values[] = {
@@ -590,6 +675,7 @@ static int wled_configure(struct wled *wled, int version)
 		{ "qcom,cs-out", &cfg->cs_out_en, },
 		{ "qcom,ext-gen", &cfg->ext_gen, },
 		{ "qcom,cabc", &cfg->cabc, },
+		{ "qcom,external-pfet", &cfg->external_pfet, },
 	};
 
 	prop_addr = of_get_address(dev->of_node, 0, NULL, NULL);
@@ -678,6 +764,38 @@ static int wled_configure(struct wled *wled, int version)
 	return 0;
 }
 
+static int wled_configure_short_irq(struct wled *wled,
+				    struct platform_device *pdev)
+{
+	int rc, short_irq;
+
+	if (!wled->has_short_detect)
+		return 0;
+
+	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+				WLED4_CTRL_REG_SHORT_PROTECT,
+				WLED4_CTRL_REG_SHORT_EN_MASK,
+				WLED4_CTRL_REG_SHORT_EN_MASK);
+	if (rc < 0)
+		return rc;
+
+	short_irq = platform_get_irq_byname(pdev, "short");
+	if (short_irq < 0) {
+		dev_dbg(&pdev->dev, "short irq is not used\n");
+		return 0;
+	}
+
+	rc = devm_request_threaded_irq(wled->dev, short_irq,
+				       NULL, wled_short_irq_handler,
+				       IRQF_ONESHOT,
+				       "wled_short_irq", wled);
+	if (rc < 0)
+		dev_err(wled->dev, "Unable to request short_irq (err:%d)\n",
+			rc);
+
+	return rc;
+}
+
 static const struct backlight_ops wled_ops = {
 	.update_status = wled_update_status,
 };
@@ -711,6 +829,7 @@ static int wled_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
+	mutex_init(&wled->lock);
 	rc = wled_configure(wled, version);
 	if (rc)
 		return rc;
@@ -725,6 +844,7 @@ static int wled_probe(struct platform_device *pdev)
 		break;
 
 	case 4:
+		wled->has_short_detect = true;
 		rc = wled4_setup(wled);
 		if (rc) {
 			dev_err(&pdev->dev, "wled4_setup failed\n");
@@ -737,6 +857,10 @@ static int wled_probe(struct platform_device *pdev)
 		break;
 	}
 
+	rc = wled_configure_short_irq(wled, pdev);
+	if (rc < 0)
+		return rc;
+
 	val = WLED_DEFAULT_BRIGHTNESS;
 	of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project

[PATCH V6 8/8] backlight: qcom-wled: Add auto string detection logic

[Kiran Gunda]

The auto string detection algorithm checks if the current WLED
sink configuration is valid. It tries enabling every sink and
checks if the OVP fault is observed. Based on this information
it detects and enables the valid sink configuration.
Auto calibration will be triggered when the OVP fault interrupts
are seen frequently thereby it tries to fix the sink configuration.

The auto-detection also kicks in when the connected LED string
of the display-backlight malfunctions (because of damage) and
requires the damaged string to be turned off to prevent the
complete panel and/or board from being damaged.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
---
 drivers/video/backlight/qcom-wled.c | 402 +++++++++++++++++++++++++++++++++++-
 1 file changed, 397 insertions(+), 5 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 556c734..7a1d3ae 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -17,10 +17,18 @@
 #define WLED_MAX_STRINGS				4
 
 #define WLED_DEFAULT_BRIGHTNESS				2048
-
+#define WLED_SOFT_START_DLY_US				10000
 #define WLED_SINK_REG_BRIGHT_MAX			0xFFF
 
 /* WLED control registers */
+#define WLED_CTRL_REG_FAULT_STATUS			0x08
+#define  WLED_CTRL_REG_ILIM_FAULT_BIT			BIT(0)
+#define  WLED_CTRL_REG_OVP_FAULT_BIT			BIT(1)
+#define  WLED4_CTRL_REG_SC_FAULT_BIT			BIT(2)
+
+#define WLED_CTRL_REG_INT_RT_STS			0x10
+#define  WLED_CTRL_REG_OVP_FAULT_STATUS			BIT(1)
+
 #define WLED_CTRL_REG_MOD_EN				0x46
 #define  WLED_CTRL_REG_MOD_EN_MASK			BIT(7)
 #define  WLED_CTRL_REG_MOD_EN_SHIFT			7
@@ -28,6 +36,8 @@
 #define WLED_CTRL_REG_FREQ				0x4c
 #define  WLED_CTRL_REG_FREQ_MASK			GENMASK(3, 0)
 
+#define WLED_CTRL_REG_FEEDBACK_CONTROL			0x48
+
 #define WLED_CTRL_REG_OVP				0x4d
 #define  WLED_CTRL_REG_OVP_MASK				GENMASK(1, 0)
 
@@ -119,6 +129,7 @@ struct wled_config {
 	bool ext_gen;
 	bool cabc;
 	bool external_pfet;
+	bool auto_detection_enabled;
 };
 
 struct wled {
@@ -127,16 +138,22 @@ struct wled {
 	struct regmap *regmap;
 	struct mutex lock;	/* Lock to avoid race from thread irq handler */
 	ktime_t last_short_event;
+	ktime_t start_ovp_fault_time;
 	u16 ctrl_addr;
 	u16 sink_addr;
 	u16 max_string_count;
+	u16 auto_detection_ovp_count;
 	u32 brightness;
 	u32 max_brightness;
 	u32 short_count;
+	u32 auto_detect_count;
 	bool disabled_by_short;
 	bool has_short_detect;
+	int ovp_irq;
+	bool ovp_irq_disabled;
 
 	struct wled_config cfg;
+	struct delayed_work ovp_work;
 	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
 };
 
@@ -181,6 +198,15 @@ static int wled4_set_brightness(struct wled *wled, u16 brightness)
 	return 0;
 }
 
+static void wled_ovp_work(struct work_struct *work)
+{
+	struct wled *wled = container_of(work,
+					 struct wled, ovp_work.work);
+
+	if (wled->ovp_irq > 0)
+		enable_irq(wled->ovp_irq);
+}
+
 static int wled_module_enable(struct wled *wled, int val)
 {
 	int rc;
@@ -192,7 +218,18 @@ static int wled_module_enable(struct wled *wled, int val)
 				WLED_CTRL_REG_MOD_EN,
 				WLED_CTRL_REG_MOD_EN_MASK,
 				val << WLED_CTRL_REG_MOD_EN_SHIFT);
-	return rc;
+	if (rc < 0)
+		return rc;
+
+	if (val) {
+		schedule_delayed_work(&wled->ovp_work, HZ / 100);
+	} else {
+		if (!cancel_delayed_work_sync(&wled->ovp_work) &&
+		    wled->ovp_irq > 0)
+			disable_irq(wled->ovp_irq);
+	}
+
+	return 0;
 }
 
 static int wled_sync_toggle(struct wled *wled)
@@ -299,6 +336,312 @@ static irqreturn_t wled_short_irq_handler(int irq, void *_wled)
 	return IRQ_HANDLED;
 }
 
+#define AUTO_DETECT_BRIGHTNESS		200
+
+static void wled_auto_string_detection(struct wled *wled)
+{
+	int rc = 0, i;
+	u32 sink_config = 0, int_sts;
+	u8 sink_test = 0, sink_valid = 0, val;
+
+	/* read configured sink configuration */
+	rc = regmap_read(wled->regmap, wled->sink_addr +
+			 WLED4_SINK_REG_CURR_SINK, &sink_config);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to read SINK configuration rc=%d\n",
+			rc);
+		goto failed_detect;
+	}
+
+	/* disable the module before starting detection */
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_CTRL_REG_MOD_EN,
+				WLED_CTRL_REG_MOD_EN_MASK, 0);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to disable WLED module rc=%d\n", rc);
+		goto failed_detect;
+	}
+
+	/* set low brightness across all sinks */
+	rc = wled4_set_brightness(wled, AUTO_DETECT_BRIGHTNESS);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to set brightness for auto detection rc=%d\n",
+			rc);
+		goto failed_detect;
+	}
+
+	if (wled->cfg.cabc) {
+		for (i = 0; i < wled->cfg.num_strings; i++) {
+			rc = regmap_update_bits(wled->regmap, wled->sink_addr +
+						WLED4_SINK_REG_STR_CABC(i),
+						WLED4_SINK_REG_STR_CABC_MASK,
+						0);
+			if (rc < 0)
+				goto failed_detect;
+		}
+	}
+
+	/* disable all sinks */
+	rc = regmap_write(wled->regmap,
+			  wled->sink_addr + WLED4_SINK_REG_CURR_SINK, 0);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to disable all sinks rc=%d\n", rc);
+		goto failed_detect;
+	}
+
+	/* iterate through the strings one by one */
+	for (i = 0; i < wled->cfg.num_strings; i++) {
+		sink_test = BIT((WLED4_SINK_REG_CURR_SINK_SHFT + i));
+
+		/* Enable feedback control */
+		rc = regmap_write(wled->regmap, wled->ctrl_addr +
+				  WLED_CTRL_REG_FEEDBACK_CONTROL, i + 1);
+		if (rc < 0) {
+			dev_err(wled->dev, "Failed to enable feedback for SINK %d rc = %d\n",
+				i + 1, rc);
+			goto failed_detect;
+		}
+
+		/* enable the sink */
+		rc = regmap_write(wled->regmap, wled->sink_addr +
+				  WLED4_SINK_REG_CURR_SINK, sink_test);
+		if (rc < 0) {
+			dev_err(wled->dev, "Failed to configure SINK %d rc=%d\n",
+				i + 1, rc);
+			goto failed_detect;
+		}
+
+		/* Enable the module */
+		rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
+					WLED_CTRL_REG_MOD_EN,
+					WLED_CTRL_REG_MOD_EN_MASK,
+					WLED_CTRL_REG_MOD_EN_MASK);
+		if (rc < 0) {
+			dev_err(wled->dev, "Failed to enable WLED module rc=%d\n",
+				rc);
+			goto failed_detect;
+		}
+
+		usleep_range(WLED_SOFT_START_DLY_US,
+			     WLED_SOFT_START_DLY_US + 1000);
+
+		rc = regmap_read(wled->regmap, wled->ctrl_addr +
+				 WLED_CTRL_REG_INT_RT_STS, &int_sts);
+		if (rc < 0) {
+			dev_err(wled->dev, "Error in reading WLED3_CTRL_INT_RT_STS rc=%d\n",
+				rc);
+			goto failed_detect;
+		}
+
+		if (int_sts & WLED_CTRL_REG_OVP_FAULT_STATUS)
+			dev_dbg(wled->dev, "WLED OVP fault detected with SINK %d\n",
+				i + 1);
+		else
+			sink_valid |= sink_test;
+
+		/* Disable the module */
+		rc = regmap_update_bits(wled->regmap,
+					wled->ctrl_addr + WLED_CTRL_REG_MOD_EN,
+					WLED_CTRL_REG_MOD_EN_MASK, 0);
+		if (rc < 0) {
+			dev_err(wled->dev, "Failed to disable WLED module rc=%d\n",
+				rc);
+			goto failed_detect;
+		}
+	}
+
+	if (!sink_valid) {
+		dev_err(wled->dev, "No valid WLED sinks found\n");
+		wled->disabled_by_short = true;
+		goto failed_detect;
+	}
+
+	if (sink_valid = sink_config) {
+		dev_dbg(wled->dev, "WLED auto-detection complete, sink-config=%x OK!\n",
+			sink_config);
+	} else {
+		dev_warn(wled->dev, "New WLED string configuration found %x\n",
+			 sink_valid);
+		sink_config = sink_valid;
+	}
+
+	/* write the new sink configuration */
+	rc = regmap_write(wled->regmap,
+			  wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
+			  sink_config);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to reconfigure the default sink rc=%d\n",
+			rc);
+		goto failed_detect;
+	}
+
+	/* Enable valid sinks */
+	for (i = 0; i < wled->cfg.num_strings; i++) {
+		if (wled->cfg.cabc) {
+			rc = regmap_update_bits(wled->regmap, wled->sink_addr +
+						WLED4_SINK_REG_STR_CABC(i),
+						WLED4_SINK_REG_STR_CABC_MASK,
+						WLED4_SINK_REG_STR_CABC_MASK);
+			if (rc < 0)
+				goto failed_detect;
+		}
+
+		if (sink_config & BIT(WLED4_SINK_REG_CURR_SINK_SHFT + i))
+			val = WLED4_SINK_REG_STR_MOD_MASK;
+		else
+			val = 0x0; /* disable modulator_en for unused sink */
+
+		rc = regmap_write(wled->regmap, wled->sink_addr +
+				  WLED4_SINK_REG_STR_MOD_EN(i), val);
+		if (rc < 0) {
+			dev_err(wled->dev, "Failed to configure MODULATOR_EN rc=%d\n",
+				rc);
+			goto failed_detect;
+		}
+	}
+
+	/* restore the feedback setting */
+	rc = regmap_write(wled->regmap,
+			  wled->ctrl_addr + WLED_CTRL_REG_FEEDBACK_CONTROL, 0);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to restore feedback setting rc=%d\n",
+			rc);
+		goto failed_detect;
+	}
+
+	/* restore brightness */
+	rc = wled4_set_brightness(wled, wled->brightness);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to set brightness after auto detection rc=%d\n",
+			rc);
+		goto failed_detect;
+	}
+
+	rc = regmap_update_bits(wled->regmap,
+				wled->ctrl_addr + WLED_CTRL_REG_MOD_EN,
+				WLED_CTRL_REG_MOD_EN_MASK,
+				WLED_CTRL_REG_MOD_EN_MASK);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to enable WLED module rc=%d\n", rc);
+		goto failed_detect;
+	}
+
+failed_detect:
+	return;
+}
+
+#define WLED_AUTO_DETECT_OVP_COUNT		5
+#define WLED_AUTO_DETECT_CNT_DLY_US		USEC_PER_SEC
+static bool wled_auto_detection_required(struct wled *wled)
+{
+	s64 elapsed_time_us;
+
+	if (!wled->cfg.auto_detection_enabled)
+		return false;
+
+	/*
+	 * Check if the OVP fault was an occasional one
+	 * or if it's firing continuously, the latter qualifies
+	 * for an auto-detection check.
+	 */
+	if (!wled->auto_detection_ovp_count) {
+		wled->start_ovp_fault_time = ktime_get();
+		wled->auto_detection_ovp_count++;
+	} else {
+		elapsed_time_us = ktime_us_delta(ktime_get(),
+						 wled->start_ovp_fault_time);
+		if (elapsed_time_us > WLED_AUTO_DETECT_CNT_DLY_US)
+			wled->auto_detection_ovp_count = 0;
+		else
+			wled->auto_detection_ovp_count++;
+
+		if (wled->auto_detection_ovp_count >+				WLED_AUTO_DETECT_OVP_COUNT) {
+			wled->auto_detection_ovp_count = 0;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static int wled_auto_detection_at_init(struct wled *wled)
+{
+	int rc;
+	u32 fault_status, rt_status;
+
+	if (!wled->cfg.auto_detection_enabled)
+		return 0;
+
+	rc = regmap_read(wled->regmap,
+			 wled->ctrl_addr + WLED_CTRL_REG_INT_RT_STS,
+			 &rt_status);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to read RT status rc=%d\n", rc);
+		return rc;
+	}
+
+	rc = regmap_read(wled->regmap,
+			 wled->ctrl_addr + WLED_CTRL_REG_FAULT_STATUS,
+			 &fault_status);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to read fault status rc=%d\n", rc);
+		return rc;
+	}
+
+	if ((rt_status & WLED_CTRL_REG_OVP_FAULT_STATUS) ||
+	    (fault_status & WLED_CTRL_REG_OVP_FAULT_BIT)) {
+		mutex_lock(&wled->lock);
+		wled_auto_string_detection(wled);
+		mutex_unlock(&wled->lock);
+	}
+
+	return rc;
+}
+
+static irqreturn_t wled_ovp_irq_handler(int irq, void *_wled)
+{
+	struct wled *wled = _wled;
+	int rc;
+	u32 int_sts, fault_sts;
+
+	rc = regmap_read(wled->regmap,
+			 wled->ctrl_addr + WLED_CTRL_REG_INT_RT_STS, &int_sts);
+	if (rc < 0) {
+		dev_err(wled->dev, "Error in reading WLED3_INT_RT_STS rc=%d\n",
+			rc);
+		return IRQ_HANDLED;
+	}
+
+	rc = regmap_read(wled->regmap, wled->ctrl_addr +
+			 WLED_CTRL_REG_FAULT_STATUS, &fault_sts);
+	if (rc < 0) {
+		dev_err(wled->dev, "Error in reading WLED_FAULT_STATUS rc=%d\n",
+			rc);
+		return IRQ_HANDLED;
+	}
+
+	if (fault_sts &
+		(WLED_CTRL_REG_OVP_FAULT_BIT | WLED_CTRL_REG_ILIM_FAULT_BIT))
+		dev_dbg(wled->dev, "WLED OVP fault detected, int_sts=%x fault_sts= %x\n",
+			int_sts, fault_sts);
+
+	if (fault_sts & WLED_CTRL_REG_OVP_FAULT_BIT) {
+		mutex_lock(&wled->lock);
+		disable_irq_nosync(wled->ovp_irq);
+
+		if (wled_auto_detection_required(wled))
+			wled_auto_string_detection(wled);
+
+		enable_irq(wled->ovp_irq);
+		wled->ovp_irq_disabled = false;
+
+		mutex_unlock(&wled->lock);
+	}
+
+	return IRQ_HANDLED;
+}
+
 static int wled3_setup(struct wled *wled)
 {
 	u16 addr;
@@ -435,8 +778,10 @@ static int wled4_setup(struct wled *wled)
 		sink_en |= 1 << temp;
 	}
 
-	if (sink_cfg = sink_en)
-		return 0;
+	if (sink_cfg = sink_en) {
+		rc = wled_auto_detection_at_init(wled);
+		return rc;
+	}
 
 	rc = regmap_update_bits(wled->regmap,
 				wled->sink_addr + WLED4_SINK_REG_CURR_SINK,
@@ -499,7 +844,9 @@ static int wled4_setup(struct wled *wled)
 		return rc;
 	}
 
-	return 0;
+	rc = wled_auto_detection_at_init(wled);
+
+	return rc;
 }
 
 static const struct wled_config wled4_config_defaults = {
@@ -510,6 +857,7 @@ static int wled4_setup(struct wled *wled)
 	.switch_freq = 11,
 	.cabc = false,
 	.external_pfet = false,
+	.auto_detection_enabled = false,
 };
 
 static const u32 wled3_boost_i_limit_values[] = {
@@ -676,6 +1024,7 @@ static int wled_configure(struct wled *wled, int version)
 		{ "qcom,ext-gen", &cfg->ext_gen, },
 		{ "qcom,cabc", &cfg->cabc, },
 		{ "qcom,external-pfet", &cfg->external_pfet, },
+		{ "qcom,auto-string-detection", &cfg->auto_detection_enabled, },
 	};
 
 	prop_addr = of_get_address(dev->of_node, 0, NULL, NULL);
@@ -796,6 +1145,42 @@ static int wled_configure_short_irq(struct wled *wled,
 	return rc;
 }
 
+static int wled_configure_ovp_irq(struct wled *wled,
+				  struct platform_device *pdev)
+{
+	int rc;
+	u32 val;
+
+	wled->ovp_irq = platform_get_irq_byname(pdev, "ovp");
+	if (wled->ovp_irq < 0) {
+		dev_dbg(&pdev->dev, "ovp irq is not used\n");
+		return 0;
+	}
+
+	rc = devm_request_threaded_irq(wled->dev, wled->ovp_irq, NULL,
+				       wled_ovp_irq_handler, IRQF_ONESHOT,
+				       "wled_ovp_irq", wled);
+	if (rc < 0) {
+		dev_err(wled->dev, "Unable to request ovp_irq (err:%d)\n",
+			rc);
+		wled->ovp_irq = 0;
+		return 0;
+	}
+
+	rc = regmap_read(wled->regmap, wled->ctrl_addr +
+			 WLED_CTRL_REG_MOD_EN, &val);
+	if (rc < 0)
+		return rc;
+
+	/* Keep OVP irq disabled until module is enabled */
+	if (!(val & WLED_CTRL_REG_MOD_EN_MASK)) {
+		disable_irq(wled->ovp_irq);
+		wled->ovp_irq_disabled = true;
+	}
+
+	return 0;
+}
+
 static const struct backlight_ops wled_ops = {
 	.update_status = wled_update_status,
 };
@@ -836,6 +1221,7 @@ static int wled_probe(struct platform_device *pdev)
 
 	switch (version) {
 	case 3:
+		wled->cfg.auto_detection_enabled = false;
 		rc = wled3_setup(wled);
 		if (rc) {
 			dev_err(&pdev->dev, "wled3_setup failed\n");
@@ -857,10 +1243,16 @@ static int wled_probe(struct platform_device *pdev)
 		break;
 	}
 
+	INIT_DELAYED_WORK(&wled->ovp_work, wled_ovp_work);
+
 	rc = wled_configure_short_irq(wled, pdev);
 	if (rc < 0)
 		return rc;
 
+	rc = wled_configure_ovp_irq(wled, pdev);
+	if (rc < 0)
+		return rc;
+
 	val = WLED_DEFAULT_BRIGHTNESS;
 	of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
 a Linux Foundation Collaborative Project