backlight: pm8941-wled: Move PM8941 WLED driver to backlight

The Qualcomm PM8941 WLED block is used for backlight and should therefor
be in the backlight framework and not in the LED framework. This moves
the driver and adapts to the backlight api instead.

Signed-off-by: Bjorn Andersson <[e-mail]>
Tested-by: Rob Clark <[e-mail]>
Acked-by: Jacek Anaszewski <[e-mail]>
Acked-by: Jingoo Han <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>

Documentation/devicetree/bindings/leds/leds-pm8941-wled.txt Documentation/devicetree/bindings/video/backlight/pm8941-wled.txt

···
 - reg: slave address
 
 Optional properties:
-- label: The label for this led
-  See Documentation/devicetree/bindings/leds/common.txt
-- linux,default-trigger: Default trigger assigned to the LED
-  See Documentation/devicetree/bindings/leds/common.txt
+- label: The name of the backlight device
 - qcom,cs-out: bool; enable current sink output
 - qcom,cabc: bool; enable content adaptive backlight control
 - qcom,ext-gen: bool; use externally generated modulator signal to dim

drivers/leds/Kconfig

···
 	  This option enabled support for the LEDs on the ARM Versatile
 	  and RealView boards. Say Y to enabled these.
 
-config LEDS_PM8941_WLED
-	tristate "LED support for the Qualcomm PM8941 WLED block"
-	depends on LEDS_CLASS
-	select REGMAP
-	help
-	  This option enables support for the 'White' LED block
-	  on Qualcomm PM8941 PMICs.
-
 comment "LED Triggers"
 source "drivers/leds/trigger/Kconfig"
 

drivers/leds/Makefile

···
 obj-$(CONFIG_LEDS_SYSCON)		+= leds-syscon.o
 obj-$(CONFIG_LEDS_VERSATILE)		+= leds-versatile.o
 obj-$(CONFIG_LEDS_MENF21BMC)		+= leds-menf21bmc.o
-obj-$(CONFIG_LEDS_PM8941_WLED)		+= leds-pm8941-wled.o
 obj-$(CONFIG_LEDS_KTD2692)		+= leds-ktd2692.o
 
 # LED SPI Drivers

drivers/leds/leds-pm8941-wled.c drivers/video/backlight/pm8941-wled.c

···
  */
 
 #include <linux/kernel.h>
-#include <linux/leds.h>
+#include <linux/backlight.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
···
 };
 
 struct pm8941_wled {
+	const char *name;
 	struct regmap *regmap;
 	u16 addr;
-
-	struct led_classdev cdev;
 
 	struct pm8941_wled_config cfg;
 };
 
-static int pm8941_wled_set(struct led_classdev *cdev,
-			   enum led_brightness value)
+static int pm8941_wled_update_status(struct backlight_device *bl)
 {
-	struct pm8941_wled *wled;
+	struct pm8941_wled *wled = bl_get_data(bl);
+	u16 val = bl->props.brightness;
 	u8 ctrl = 0;
-	u16 val;
 	int rc;
 	int i;
 
-	wled = container_of(cdev, struct pm8941_wled, cdev);
+	if (bl->props.power != FB_BLANK_UNBLANK ||
+	    bl->props.fb_blank != FB_BLANK_UNBLANK ||
+	    bl->props.state & BL_CORE_FBBLANK)
+		val = 0;
 
-	if (value != 0)
+	if (val != 0)
 		ctrl = PM8941_WLED_REG_MOD_EN_BIT;
-
-	val = value * PM8941_WLED_REG_VAL_MAX / LED_FULL;
 
 	rc = regmap_update_bits(wled->regmap,
 			wled->addr + PM8941_WLED_REG_MOD_EN,
···
 			wled->addr + PM8941_WLED_REG_SYNC,
 			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
 	return rc;
-}
-
-static void pm8941_wled_set_brightness(struct led_classdev *cdev,
-				       enum led_brightness value)
-{
-	if (pm8941_wled_set(cdev, value)) {
-		dev_err(cdev->dev, "Unable to set brightness\n");
-		return;
-	}
-	cdev->brightness = value;
 }
 
 static int pm8941_wled_setup(struct pm8941_wled *wled)
···
 	}
 	wled->addr = val;
 
-	rc = of_property_read_string(dev->of_node, "label", &wled->cdev.name);
+	rc = of_property_read_string(dev->of_node, "label", &wled->name);
 	if (rc)
-		wled->cdev.name = dev->of_node->name;
-
-	wled->cdev.default_trigger = of_get_property(dev->of_node,
-			"linux,default-trigger", NULL);
+		wled->name = dev->of_node->name;
 
 	*cfg = pm8941_wled_config_defaults;
 	for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
···
 	return 0;
 }
 
+static const struct backlight_ops pm8941_wled_ops = {
+	.update_status = pm8941_wled_update_status,
+};
+
 static int pm8941_wled_probe(struct platform_device *pdev)
 {
+	struct backlight_properties props;
+	struct backlight_device *bl;
 	struct pm8941_wled *wled;
 	struct regmap *regmap;
 	int rc;
···
 	if (rc)
 		return rc;
 
-	wled->cdev.brightness_set = pm8941_wled_set_brightness;
-
-	rc = devm_led_classdev_register(&pdev->dev, &wled->cdev);
-	if (rc)
-		return rc;
-
-	platform_set_drvdata(pdev, wled);
+	memset(&props, 0, sizeof(struct backlight_properties));
+	props.type = BACKLIGHT_RAW;
+	props.max_brightness = PM8941_WLED_REG_VAL_MAX;
+	bl = devm_backlight_device_register(&pdev->dev, wled->name,
+					    &pdev->dev, wled,
+					    &pm8941_wled_ops, &props);
+	if (IS_ERR(bl))
+		return PTR_ERR(bl);
 
 	return 0;
 };
···
 
 MODULE_DESCRIPTION("pm8941 wled driver");
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:pm8941-wled");

drivers/video/backlight/Kconfig

···
 	  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"
+	select REGMAP
+	help
+	  If you have the Qualcomm PM8941, say Y to enable a driver for the
+	  WLED block.
+
 config BACKLIGHT_SAHARA
 	tristate "Tabletkiosk Sahara Touch-iT Backlight Driver"
 	depends on X86

drivers/video/backlight/Makefile

···
 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_SAHARA)		+= kb3886_bl.o
 obj-$(CONFIG_BACKLIGHT_SKY81452)	+= sky81452-backlight.o