ARM: SAMSUNG: Add PWM backlight support on Samsung S5P6440
This patch adds support for LCD backlight control using PWM timer
for Samsung SMDK6440 board.
Signed-off-by: Banajit Goswami <banajit.g@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/arch/arm/mach-s5p64x0/Kconfig b/arch/arm/mach-s5p64x0/Kconfig
index 164d278..be5888a 100644
--- a/arch/arm/mach-s5p64x0/Kconfig
+++ b/arch/arm/mach-s5p64x0/Kconfig
@@ -34,6 +34,7 @@
select S3C_DEV_WDT
select S3C64XX_DEV_SPI
select SAMSUNG_DEV_ADC
+ select SAMSUNG_DEV_PWM
select SAMSUNG_DEV_TS
select S5P64X0_SETUP_I2C1
help
diff --git a/arch/arm/mach-s5p64x0/mach-smdk6440.c b/arch/arm/mach-s5p64x0/mach-smdk6440.c
index e5beb84..366dca4 100644
--- a/arch/arm/mach-s5p64x0/mach-smdk6440.c
+++ b/arch/arm/mach-s5p64x0/mach-smdk6440.c
@@ -22,6 +22,7 @@
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/gpio.h>
+#include <linux/pwm_backlight.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
@@ -32,6 +33,7 @@
#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/i2c.h>
+#include <mach/regs-gpio.h>
#include <plat/regs-serial.h>
#include <plat/gpio-cfg.h>
@@ -88,6 +90,45 @@
},
};
+static int smdk6440_backlight_init(struct device *dev)
+{
+ int ret;
+
+ ret = gpio_request(S5P6440_GPF(15), "Backlight");
+ if (ret) {
+ printk(KERN_ERR "failed to request GPF for PWM-OUT1\n");
+ return ret;
+ }
+
+ /* Configure GPIO pin with S5P6440_GPF15_PWM_TOUT1 */
+ s3c_gpio_cfgpin(S5P6440_GPF(15), S3C_GPIO_SFN(2));
+
+ return 0;
+}
+
+static void smdk6440_backlight_exit(struct device *dev)
+{
+ s3c_gpio_cfgpin(S5P6440_GPF(15), S3C_GPIO_OUTPUT);
+ gpio_free(S5P6440_GPF(15));
+}
+
+static struct platform_pwm_backlight_data smdk6440_backlight_data = {
+ .pwm_id = 1,
+ .max_brightness = 255,
+ .dft_brightness = 255,
+ .pwm_period_ns = 78770,
+ .init = smdk6440_backlight_init,
+ .exit = smdk6440_backlight_exit,
+};
+
+static struct platform_device smdk6440_backlight_device = {
+ .name = "pwm-backlight",
+ .dev = {
+ .parent = &s3c_device_timer[1].dev,
+ .platform_data = &smdk6440_backlight_data,
+ },
+};
+
static struct platform_device *smdk6440_devices[] __initdata = {
&s3c_device_adc,
&s3c_device_rtc,
@@ -97,6 +138,8 @@
&s3c_device_wdt,
&samsung_asoc_dma,
&s5p6440_device_iis,
+ &s3c_device_timer[1],
+ &smdk6440_backlight_device,
};
static struct s3c2410_platform_i2c s5p6440_i2c0_data __initdata = {
