diff options
Diffstat (limited to 'arch/arm/plat-samsung/dev-backlight.c')
| -rw-r--r-- | arch/arm/plat-samsung/dev-backlight.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/dev-backlight.c b/arch/arm/plat-samsung/dev-backlight.c new file mode 100644 index 00000000000..3cedd4c407a --- /dev/null +++ b/arch/arm/plat-samsung/dev-backlight.c @@ -0,0 +1,149 @@ +/* linux/arch/arm/plat-samsung/dev-backlight.c + * + * Copyright (c) 2011 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * Common infrastructure for PWM Backlight for Samsung boards + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/gpio.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/pwm_backlight.h> + +#include <plat/devs.h> +#include <plat/gpio-cfg.h> +#include <plat/backlight.h> + +static int samsung_bl_init(struct device *dev) +{ + int ret = 0; + struct platform_device *timer_dev = + container_of(dev->parent, struct platform_device, dev); + struct samsung_bl_gpio_info *bl_gpio_info = + timer_dev->dev.platform_data; + + ret = gpio_request(bl_gpio_info->no, "Backlight"); + if (ret) { + printk(KERN_ERR "failed to request GPIO for LCD Backlight\n"); + return ret; + } + + /* Configure GPIO pin with specific GPIO function for PWM timer */ + s3c_gpio_cfgpin(bl_gpio_info->no, bl_gpio_info->func); + + return 0; +} + +static void samsung_bl_exit(struct device *dev) +{ + struct platform_device *timer_dev = + container_of(dev->parent, struct platform_device, dev); + struct samsung_bl_gpio_info *bl_gpio_info = + timer_dev->dev.platform_data; + + s3c_gpio_cfgpin(bl_gpio_info->no, S3C_GPIO_OUTPUT); + gpio_free(bl_gpio_info->no); +} + +/* Initialize few important fields of platform_pwm_backlight_data + * structure with default values. These fields can be overridden by + * board-specific values sent from machine file. + * For ease of operation, these fields are initialized with values + * used by most samsung boards. + * Users has the option of sending info about other parameters + * for their specific boards + */ + +static struct platform_pwm_backlight_data samsung_dfl_bl_data __initdata = { + .max_brightness = 255, + .dft_brightness = 255, + .pwm_period_ns = 78770, + .init = samsung_bl_init, + .exit = samsung_bl_exit, +}; + +static struct platform_device samsung_dfl_bl_device __initdata = { + .name = "pwm-backlight", +}; + +/* samsung_bl_set - Set board specific data (if any) provided by user for + * PWM Backlight control and register specific PWM and backlight device. + * @gpio_info: structure containing GPIO info for PWM timer + * @bl_data: structure containing Backlight control data + */ +void samsung_bl_set(struct samsung_bl_gpio_info *gpio_info, + struct platform_pwm_backlight_data *bl_data) +{ + int ret = 0; + struct platform_device *samsung_bl_device; + struct platform_pwm_backlight_data *samsung_bl_data; + + samsung_bl_device = kmemdup(&samsung_dfl_bl_device, + sizeof(struct platform_device), GFP_KERNEL); + if (!samsung_bl_device) { + printk(KERN_ERR "%s: no memory for platform dev\n", __func__); + return; + } + + samsung_bl_data = s3c_set_platdata(&samsung_dfl_bl_data, + sizeof(struct platform_pwm_backlight_data), samsung_bl_device); + if (!samsung_bl_data) { + printk(KERN_ERR "%s: no memory for platform dev\n", __func__); + goto err_data; + } + + /* Copy board specific data provided by user */ + samsung_bl_data->pwm_id = bl_data->pwm_id; + samsung_bl_device->dev.parent = + &s3c_device_timer[samsung_bl_data->pwm_id].dev; + + if (bl_data->max_brightness) + samsung_bl_data->max_brightness = bl_data->max_brightness; + if (bl_data->dft_brightness) + samsung_bl_data->dft_brightness = bl_data->dft_brightness; + if (bl_data->lth_brightness) + samsung_bl_data->lth_brightness = bl_data->lth_brightness; + if (bl_data->pwm_period_ns) + samsung_bl_data->pwm_period_ns = bl_data->pwm_period_ns; + if (bl_data->init) + samsung_bl_data->init = bl_data->init; + if (bl_data->notify) + samsung_bl_data->notify = bl_data->notify; + if (bl_data->exit) + samsung_bl_data->exit = bl_data->exit; + if (bl_data->check_fb) + samsung_bl_data->check_fb = bl_data->check_fb; + + /* Keep the GPIO info for future use */ + s3c_device_timer[samsung_bl_data->pwm_id].dev.platform_data = gpio_info; + + /* Register the specific PWM timer dev for Backlight control */ + ret = platform_device_register( + &s3c_device_timer[samsung_bl_data->pwm_id]); + if (ret) { + printk(KERN_ERR "failed to register pwm timer for backlight: %d\n", ret); + goto err_plat_reg1; + } + + /* Register the Backlight dev */ + ret = platform_device_register(samsung_bl_device); + if (ret) { + printk(KERN_ERR "failed to register backlight device: %d\n", ret); + goto err_plat_reg2; + } + + return; + +err_plat_reg2: + platform_device_unregister(&s3c_device_timer[samsung_bl_data->pwm_id]); +err_plat_reg1: + kfree(samsung_bl_data); +err_data: + kfree(samsung_bl_device); + return; +} |