diff options
Diffstat (limited to 'kernel/arch/arm/plat-samsung/dev-backlight.c')
-rw-r--r-- | kernel/arch/arm/plat-samsung/dev-backlight.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/kernel/arch/arm/plat-samsung/dev-backlight.c b/kernel/arch/arm/plat-samsung/dev-backlight.c new file mode 100644 index 000000000..2157c5b53 --- /dev/null +++ b/kernel/arch/arm/plat-samsung/dev-backlight.c @@ -0,0 +1,152 @@ +/* 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/slab.h> +#include <linux/io.h> +#include <linux/pwm_backlight.h> + +#include <plat/devs.h> +#include <plat/gpio-cfg.h> +#include <plat/backlight.h> + +struct samsung_bl_drvdata { + struct platform_pwm_backlight_data plat_data; + struct samsung_bl_gpio_info *gpio_info; +}; + +static int samsung_bl_init(struct device *dev) +{ + int ret = 0; + struct platform_pwm_backlight_data *pdata = dev->platform_data; + struct samsung_bl_drvdata *drvdata = container_of(pdata, + struct samsung_bl_drvdata, plat_data); + struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info; + + 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_pwm_backlight_data *pdata = dev->platform_data; + struct samsung_bl_drvdata *drvdata = container_of(pdata, + struct samsung_bl_drvdata, plat_data); + struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info; + + 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 samsung_bl_drvdata samsung_dfl_bl_data __initdata = { + .plat_data = { + .max_brightness = 255, + .dft_brightness = 255, + .pwm_period_ns = 78770, + .enable_gpio = -1, + .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 __init 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 samsung_bl_drvdata *samsung_bl_drvdata; + 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_drvdata = kmemdup(&samsung_dfl_bl_data, + sizeof(samsung_dfl_bl_data), GFP_KERNEL); + if (!samsung_bl_drvdata) { + printk(KERN_ERR "%s: no memory for platform dev\n", __func__); + goto err_data; + } + samsung_bl_device->dev.platform_data = &samsung_bl_drvdata->plat_data; + samsung_bl_drvdata->gpio_info = gpio_info; + samsung_bl_data = &samsung_bl_drvdata->plat_data; + + /* Copy board specific data provided by user */ + samsung_bl_data->pwm_id = bl_data->pwm_id; + samsung_bl_device->dev.parent = &samsung_device_pwm.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->enable_gpio >= 0) + samsung_bl_data->enable_gpio = bl_data->enable_gpio; + 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->notify_after) + samsung_bl_data->notify_after = bl_data->notify_after; + 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; + + /* 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: + kfree(samsung_bl_data); +err_data: + kfree(samsung_bl_device); + return; +} |