backlight: corgi: Convert to use GPIO descriptors

The code in the Corgi backlight driver can be considerably
simplified by moving to GPIO descriptors and lookup tables
from the board files instead of passing GPIO numbers using
the old API.

Make sure to encode inversion semantics for the Akita and
Spitz platforms inside the GPIO lookup table and drop the
custom inversion semantics from the driver.

All in-tree users are converted in this patch.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

arch/arm/mach-pxa/corgi.c

@@ -563,13 +563,20 @@ static void corgi_bl_kick_battery(void)
 	}
 }
 
+static struct gpiod_lookup_table corgi_lcdcon_gpio_table = {
+	.dev_id = "spi1.1",
+	.table = {
+		GPIO_LOOKUP("gpio-pxa", CORGI_GPIO_BACKLIGHT_CONT,
+			    "BL_CONT", GPIO_ACTIVE_HIGH),
+		{ },
+	},
+};
+
 static struct corgi_lcd_platform_data corgi_lcdcon_info = {
 	.init_mode		= CORGI_LCD_MODE_VGA,
 	.max_intensity		= 0x2f,
 	.default_intensity	= 0x1f,
 	.limit_mask		= 0x0b,
-	.gpio_backlight_cont	= CORGI_GPIO_BACKLIGHT_CONT,
-	.gpio_backlight_on	= -1,
 	.kick_battery		= corgi_bl_kick_battery,
 };
 
@@ -609,6 +616,7 @@ static struct spi_board_info corgi_spi_devices[] = {
 static void __init corgi_init_spi(void)
 {
 	pxa2xx_set_spi_info(1, &corgi_spi_info);
+	gpiod_add_lookup_table(&corgi_lcdcon_gpio_table);
 	spi_register_board_info(ARRAY_AND_SIZE(corgi_spi_devices));
 }
 #else

arch/arm/mach-pxa/spitz.c

@@ -525,13 +525,33 @@ static void spitz_bl_kick_battery(void)
 	}
 }
 
+static struct gpiod_lookup_table spitz_lcdcon_gpio_table = {
+	.dev_id = "spi2.1",
+	.table = {
+		GPIO_LOOKUP("gpio-pxa", SPITZ_GPIO_BACKLIGHT_CONT,
+			    "BL_CONT", GPIO_ACTIVE_LOW),
+		GPIO_LOOKUP("gpio-pxa", SPITZ_GPIO_BACKLIGHT_ON,
+			    "BL_ON", GPIO_ACTIVE_HIGH),
+		{ },
+	},
+};
+
+static struct gpiod_lookup_table akita_lcdcon_gpio_table = {
+	.dev_id = "spi2.1",
+	.table = {
+		GPIO_LOOKUP("gpio-pxa", AKITA_GPIO_BACKLIGHT_CONT,
+			    "BL_CONT", GPIO_ACTIVE_LOW),
+		GPIO_LOOKUP("gpio-pxa", AKITA_GPIO_BACKLIGHT_ON,
+			    "BL_ON", GPIO_ACTIVE_HIGH),
+		{ },
+	},
+};
+
 static struct corgi_lcd_platform_data spitz_lcdcon_info = {
 	.init_mode		= CORGI_LCD_MODE_VGA,
 	.max_intensity		= 0x2f,
 	.default_intensity	= 0x1f,
 	.limit_mask		= 0x0b,
-	.gpio_backlight_cont	= SPITZ_GPIO_BACKLIGHT_CONT,
-	.gpio_backlight_on	= SPITZ_GPIO_BACKLIGHT_ON,
 	.kick_battery		= spitz_bl_kick_battery,
 };
 
@@ -574,12 +594,10 @@ static struct pxa2xx_spi_controller spitz_spi_info = {
 
 static void __init spitz_spi_init(void)
 {
-	struct corgi_lcd_platform_data *lcd_data = &spitz_lcdcon_info;
-
-	if (machine_is_akita()) {
-		lcd_data->gpio_backlight_cont = AKITA_GPIO_BACKLIGHT_CONT;
-		lcd_data->gpio_backlight_on = AKITA_GPIO_BACKLIGHT_ON;
-	}
+	if (machine_is_akita())
+		gpiod_add_lookup_table(&akita_lcdcon_gpio_table);
+	else
+		gpiod_add_lookup_table(&spitz_lcdcon_gpio_table);
 
 	pxa2xx_set_spi_info(2, &spitz_spi_info);
 	spi_register_board_info(ARRAY_AND_SIZE(spitz_spi_devices));

drivers/video/backlight/corgi_lcd.c

@@ -15,7 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/delay.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/fb.h>
 #include <linux/lcd.h>
 #include <linux/spi/spi.h>
@@ -90,9 +90,8 @@ struct corgi_lcd {
 	int	mode;
 	char	buf[2];
 
-	int	gpio_backlight_on;
-	int	gpio_backlight_cont;
-	int	gpio_backlight_cont_inverted;
+	struct gpio_desc *backlight_on;
+	struct gpio_desc *backlight_cont;
 
 	void (*kick_battery)(void);
 };
@@ -403,13 +402,13 @@ static int corgi_bl_set_intensity(struct corgi_lcd *lcd, int intensity)
 	corgi_ssp_lcdtg_send(lcd, DUTYCTRL_ADRS, intensity);
 
 	/* Bit 5 via GPIO_BACKLIGHT_CONT */
-	cont = !!(intensity & 0x20) ^ lcd->gpio_backlight_cont_inverted;
+	cont = !!(intensity & 0x20);
 
-	if (gpio_is_valid(lcd->gpio_backlight_cont))
-		gpio_set_value_cansleep(lcd->gpio_backlight_cont, cont);
+	if (lcd->backlight_cont)
+		gpiod_set_value_cansleep(lcd->backlight_cont, cont);
 
-	if (gpio_is_valid(lcd->gpio_backlight_on))
-		gpio_set_value_cansleep(lcd->gpio_backlight_on, intensity);
+	if (lcd->backlight_on)
+		gpiod_set_value_cansleep(lcd->backlight_on, intensity);
 
 	if (lcd->kick_battery)
 		lcd->kick_battery();
@@ -482,48 +481,17 @@ static int setup_gpio_backlight(struct corgi_lcd *lcd,
 				struct corgi_lcd_platform_data *pdata)
 {
 	struct spi_device *spi = lcd->spi_dev;
-	int err;
 
-	lcd->gpio_backlight_on = -1;
-	lcd->gpio_backlight_cont = -1;
+	lcd->backlight_on = devm_gpiod_get_optional(&spi->dev,
+						    "BL_ON", GPIOD_OUT_LOW);
+	if (IS_ERR(lcd->backlight_on))
+		return PTR_ERR(lcd->backlight_on);
 
-	if (gpio_is_valid(pdata->gpio_backlight_on)) {
-		err = devm_gpio_request(&spi->dev, pdata->gpio_backlight_on,
-					"BL_ON");
-		if (err) {
-			dev_err(&spi->dev,
-				"failed to request GPIO%d for backlight_on\n",
-				pdata->gpio_backlight_on);
-			return err;
-		}
+	lcd->backlight_cont = devm_gpiod_get_optional(&spi->dev, "BL_CONT",
+						      GPIOD_OUT_LOW);
+	if (IS_ERR(lcd->backlight_cont))
+		return PTR_ERR(lcd->backlight_cont);
 
-		lcd->gpio_backlight_on = pdata->gpio_backlight_on;
-		gpio_direction_output(lcd->gpio_backlight_on, 0);
-	}
-
-	if (gpio_is_valid(pdata->gpio_backlight_cont)) {
-		err = devm_gpio_request(&spi->dev, pdata->gpio_backlight_cont,
-					"BL_CONT");
-		if (err) {
-			dev_err(&spi->dev,
-				"failed to request GPIO%d for backlight_cont\n",
-				pdata->gpio_backlight_cont);
-			return err;
-		}
-
-		lcd->gpio_backlight_cont = pdata->gpio_backlight_cont;
-
-		/* spitz and akita use both GPIOs for backlight, and
-		 * have inverted polarity of GPIO_BACKLIGHT_CONT
-		 */
-		if (gpio_is_valid(lcd->gpio_backlight_on)) {
-			lcd->gpio_backlight_cont_inverted = 1;
-			gpio_direction_output(lcd->gpio_backlight_cont, 1);
-		} else {
-			lcd->gpio_backlight_cont_inverted = 0;
-			gpio_direction_output(lcd->gpio_backlight_cont, 0);
-		}
-	}
 	return 0;
 }
 

include/linux/spi/corgi_lcd.h

@@ -11,9 +11,6 @@ struct corgi_lcd_platform_data {
 	int	default_intensity;
 	int	limit_mask;
 
-	int	gpio_backlight_on;	/* -1 if n/a */
-	int	gpio_backlight_cont;	/* -1 if n/a */
-
 	void (*notify)(int intensity);
 	void (*kick_battery)(void);
 };