[PATCH] drivers: fbtft: Refactor backlight logic

[qianfanguijin@xxxxxxx]

From: qianfan Zhao <qianfanguijin@xxxxxxx>

Control led gpios by using GPIO_ACTIVE flags, don't detect the polarity
by reading the gpio value when probe.

Signed-off-by: qianfan Zhao <qianfanguijin@xxxxxxx>
---
 drivers/staging/fbtft/fbtft-core.c | 54 +++++++++++++++++-------------
 drivers/staging/fbtft/fbtft.h      |  1 -
 2 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index ed992ca605eb..37548848af99 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -70,14 +70,14 @@ void fbtft_dbg_hex(const struct device *dev, int groupsize,
 }
 EXPORT_SYMBOL(fbtft_dbg_hex);
 
-static int fbtft_request_one_gpio(struct fbtft_par *par,
-				  const char *name, int index,
-				  struct gpio_desc **gpiop)
+static int fbtft_request_one_gpio_with_flags(struct fbtft_par *par,
+					     const char *name, int index,
+					     enum gpiod_flags flags,
+					     struct gpio_desc **gpiop)
 {
 	struct device *dev = par->info->device;
 
-	*gpiop = devm_gpiod_get_index_optional(dev, name, index,
-					       GPIOD_OUT_LOW);
+	*gpiop = devm_gpiod_get_index_optional(dev, name, index, flags);
 	if (IS_ERR(*gpiop))
 		return dev_err_probe(dev, PTR_ERR(*gpiop), "Failed to request %s GPIO\n", name);
 
@@ -87,6 +87,25 @@ static int fbtft_request_one_gpio(struct fbtft_par *par,
 	return 0;
 }
 
+static int fbtft_request_one_gpio(struct fbtft_par *par,
+				  const char *name, int index,
+				  struct gpio_desc **gpiop)
+{
+	enum gpiod_flags flags = GPIOD_OUT_LOW;
+
+	return fbtft_request_one_gpio_with_flags(par, name, index, flags, gpiop);
+}
+
+static int fbtft_request_led_gpio(struct fbtft_par *par,
+				  const char *name, int index,
+				  struct gpio_desc **gpiop)
+{
+	enum gpiod_flags flags = GPIOD_OUT_HIGH;
+
+	/* request and turn on backlight */
+	return fbtft_request_one_gpio_with_flags(par, name, index, flags, gpiop);
+}
+
 static int fbtft_request_gpios(struct fbtft_par *par)
 {
 	int i;
@@ -115,7 +134,7 @@ static int fbtft_request_gpios(struct fbtft_par *par)
 					     &par->gpio.db[i]);
 		if (ret)
 			return ret;
-		ret = fbtft_request_one_gpio(par, "led", i,
+		ret = fbtft_request_led_gpio(par, "led", i,
 					     &par->gpio.led[i]);
 		if (ret)
 			return ret;
@@ -132,17 +151,16 @@ static int fbtft_request_gpios(struct fbtft_par *par)
 static int fbtft_backlight_update_status(struct backlight_device *bd)
 {
 	struct fbtft_par *par = bl_get_data(bd);
-	bool polarity = par->polarity;
 
 	fbtft_par_dbg(DEBUG_BACKLIGHT, par,
-		      "%s: polarity=%d, power=%d, fb_blank=%d\n",
-		      __func__, polarity, bd->props.power, bd->props.fb_blank);
+		      "%s: power=%d, fb_blank=%d\n",
+		      __func__, bd->props.power, bd->props.fb_blank);
 
 	if ((bd->props.power == FB_BLANK_UNBLANK) &&
 	    (bd->props.fb_blank == FB_BLANK_UNBLANK))
-		gpiod_set_value(par->gpio.led[0], polarity);
+		gpiod_set_value(par->gpio.led[0], 1);
 	else
-		gpiod_set_value(par->gpio.led[0], !polarity);
+		gpiod_set_value(par->gpio.led[0], 0);
 
 	return 0;
 }
@@ -179,11 +197,7 @@ void fbtft_register_backlight(struct fbtft_par *par)
 	}
 
 	bl_props.type = BACKLIGHT_RAW;
-	/* Assume backlight is off, get polarity from current state of pin */
-	bl_props.power = FB_BLANK_POWERDOWN;
-	if (!gpiod_get_value(par->gpio.led[0]))
-		par->polarity = true;
-
+	bl_props.power = FB_BLANK_UNBLANK;
 	bd = backlight_device_register(dev_driver_string(par->info->device),
 				       par->info->device, par,
 				       &fbtft_bl_ops, &bl_props);
@@ -853,14 +867,6 @@ int fbtft_register_framebuffer(struct fb_info *fb_info)
 		 fb_info->fix.smem_len >> 10, text1,
 		 HZ / fb_info->fbdefio->delay, text2);
 
-#ifdef CONFIG_FB_BACKLIGHT
-	/* Turn on backlight if available */
-	if (fb_info->bl_dev) {
-		fb_info->bl_dev->props.power = FB_BLANK_UNBLANK;
-		fb_info->bl_dev->ops->update_status(fb_info->bl_dev);
-	}
-#endif
-
 	return 0;
 
 reg_fail:
diff --git a/drivers/staging/fbtft/fbtft.h b/drivers/staging/fbtft/fbtft.h
index 76f8c090a837..6751c129df4d 100644
--- a/drivers/staging/fbtft/fbtft.h
+++ b/drivers/staging/fbtft/fbtft.h
@@ -228,7 +228,6 @@ struct fbtft_par {
 	ktime_t update_time;
 	bool bgr;
 	void *extra;
-	bool polarity;
 };
 
 #define NUMARGS(...)  (sizeof((int[]){__VA_ARGS__}) / sizeof(int))
-- 
2.17.1