ARM: h1940: Fix backlight and LCD power functions

Current implementation of LCD and backlight power control functions
is not complete, as result PDA consumes power in suspend.
Fix this issue by managing state of some latch bits, just like
WinMobile does.
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

arch/arm/mach-s3c2410/include/mach/h1940-latch.h

@@ -20,7 +20,7 @@
 
 /* SD layer latch */
 
-#define H1940_LATCH_SDQ1		H1940_LATCH_GPIO(0)
+#define H1940_LATCH_LCD_P0		H1940_LATCH_GPIO(0)
 #define H1940_LATCH_LCD_P1		H1940_LATCH_GPIO(1)
 #define H1940_LATCH_LCD_P2		H1940_LATCH_GPIO(2)
 #define H1940_LATCH_LCD_P3		H1940_LATCH_GPIO(3)

arch/arm/mach-s3c2410/mach-h1940.c

@@ -106,13 +106,7 @@ static struct s3c2410_uartcfg h1940_uartcfgs[] __initdata = {
 
 /* Board control latch control */
 
-static unsigned int latch_state = H1940_LATCH_BIT(H1940_LATCH_LCD_P4) |
-	H1940_LATCH_BIT(H1940_LATCH_SM803_ENABLE)	|
-	H1940_LATCH_BIT(H1940_LATCH_SDQ1)			|
-	H1940_LATCH_BIT(H1940_LATCH_LCD_P1)			|
-	H1940_LATCH_BIT(H1940_LATCH_LCD_P2)			|
-	H1940_LATCH_BIT(H1940_LATCH_LCD_P3)			|
-	H1940_LATCH_BIT(H1940_LATCH_MAX1698_nSHUTDOWN);
+static unsigned int latch_state;
 
 static void h1940_latch_control(unsigned int clear, unsigned int set)
 {
@@ -275,15 +269,32 @@ static int h1940_backlight_init(struct device *dev)
 	gpio_direction_output(S3C2410_GPB(0), 0);
 	s3c_gpio_setpull(S3C2410_GPB(0), S3C_GPIO_PULL_NONE);
 	s3c_gpio_cfgpin(S3C2410_GPB(0), S3C2410_GPB0_TOUT0);
+	gpio_set_value(H1940_LATCH_MAX1698_nSHUTDOWN, 1);
 
 	return 0;
 }
 
+static int h1940_backlight_notify(struct device *dev, int brightness)
+{
+	if (!brightness) {
+		gpio_direction_output(S3C2410_GPB(0), 1);
+		gpio_set_value(H1940_LATCH_MAX1698_nSHUTDOWN, 0);
+	} else {
+		gpio_direction_output(S3C2410_GPB(0), 0);
+		s3c_gpio_setpull(S3C2410_GPB(0), S3C_GPIO_PULL_NONE);
+		s3c_gpio_cfgpin(S3C2410_GPB(0), S3C2410_GPB0_TOUT0);
+		gpio_set_value(H1940_LATCH_MAX1698_nSHUTDOWN, 1);
+	}
+	return brightness;
+}
+
 static void h1940_backlight_exit(struct device *dev)
 {
 	gpio_direction_output(S3C2410_GPB(0), 1);
+	gpio_set_value(H1940_LATCH_MAX1698_nSHUTDOWN, 0);
 }
 
+
 static struct platform_pwm_backlight_data backlight_data = {
 	.pwm_id         = 0,
 	.max_brightness = 100,
@@ -291,6 +302,7 @@ static struct platform_pwm_backlight_data backlight_data = {
 	/* tcnt = 0x31 */
 	.pwm_period_ns  = 36296,
 	.init           = h1940_backlight_init,
+	.notify		= h1940_backlight_notify,
 	.exit           = h1940_backlight_exit,
 };
 
@@ -309,19 +321,37 @@ static void h1940_lcd_power_set(struct plat_lcd_data *pd,
 	int value;
 
 	if (!power) {
-		/* set to 3ec */
-		gpio_direction_output(S3C2410_GPC(0), 0);
+		gpio_set_value(S3C2410_GPC(0), 0);
 		/* wait for 3ac */
 		do {
 			value = gpio_get_value(S3C2410_GPC(6));
 		} while (value);
-		/* set to 38c */
-		gpio_direction_output(S3C2410_GPC(5), 0);
+
+		gpio_set_value(H1940_LATCH_LCD_P2, 0);
+		gpio_set_value(H1940_LATCH_LCD_P3, 0);
+		gpio_set_value(H1940_LATCH_LCD_P4, 0);
+
+		gpio_direction_output(S3C2410_GPC(1), 0);
+		gpio_direction_output(S3C2410_GPC(4), 0);
+
+		gpio_set_value(H1940_LATCH_LCD_P1, 0);
+		gpio_set_value(H1940_LATCH_LCD_P0, 0);
+
+		gpio_set_value(S3C2410_GPC(5), 0);
+
 	} else {
-		/* Set to 3ac */
-		gpio_direction_output(S3C2410_GPC(5), 1);
-		/* Set to 3ad */
-		gpio_direction_output(S3C2410_GPC(0), 1);
+		gpio_set_value(H1940_LATCH_LCD_P0, 1);
+		gpio_set_value(H1940_LATCH_LCD_P1, 1);
+
+		s3c_gpio_cfgpin(S3C2410_GPC(1), S3C_GPIO_SFN(2));
+		s3c_gpio_cfgpin(S3C2410_GPC(4), S3C_GPIO_SFN(2));
+
+		gpio_set_value(S3C2410_GPC(5), 1);
+		gpio_set_value(S3C2410_GPC(0), 1);
+
+		gpio_set_value(H1940_LATCH_LCD_P3, 1);
+		gpio_set_value(H1940_LATCH_LCD_P2, 1);
+		gpio_set_value(H1940_LATCH_LCD_P4, 1);
 	}
 }
 
@@ -366,6 +396,8 @@ static void __init h1940_map_io(void)
 #endif
 	s3c_pm_init();
 
+	/* Add latch gpio chip, set latch initial value */
+	h1940_latch_control(0, 0);
 	WARN_ON(gpiochip_add(&h1940_latch_gpiochip));
 }
 
@@ -404,9 +436,27 @@ static void __init h1940_init(void)
 	writel(tmp, S3C2410_UPLLCON);
 
 	gpio_request(S3C2410_GPC(0), "LCD power");
+	gpio_request(S3C2410_GPC(1), "LCD power");
+	gpio_request(S3C2410_GPC(4), "LCD power");
 	gpio_request(S3C2410_GPC(5), "LCD power");
 	gpio_request(S3C2410_GPC(6), "LCD power");
+	gpio_request(H1940_LATCH_LCD_P0, "LCD power");
+	gpio_request(H1940_LATCH_LCD_P1, "LCD power");
+	gpio_request(H1940_LATCH_LCD_P2, "LCD power");
+	gpio_request(H1940_LATCH_LCD_P3, "LCD power");
+	gpio_request(H1940_LATCH_LCD_P4, "LCD power");
+	gpio_request(H1940_LATCH_MAX1698_nSHUTDOWN, "LCD power");
+	gpio_direction_output(S3C2410_GPC(0), 0);
+	gpio_direction_output(S3C2410_GPC(1), 0);
+	gpio_direction_output(S3C2410_GPC(4), 0);
+	gpio_direction_output(S3C2410_GPC(5), 0);
 	gpio_direction_input(S3C2410_GPC(6));
+	gpio_direction_output(H1940_LATCH_LCD_P0, 0);
+	gpio_direction_output(H1940_LATCH_LCD_P1, 0);
+	gpio_direction_output(H1940_LATCH_LCD_P2, 0);
+	gpio_direction_output(H1940_LATCH_LCD_P3, 0);
+	gpio_direction_output(H1940_LATCH_LCD_P4, 0);
+	gpio_direction_output(H1940_LATCH_MAX1698_nSHUTDOWN, 0);
 
 	gpio_request(H1940_LATCH_USB_DP, "USB pullup");
 	gpio_direction_output(H1940_LATCH_USB_DP, 0);