1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (c) 2011 Samsung Electronics Co., Ltd.
  4//              http://www.samsung.com
  5//
  6// Common infrastructure for PWM Backlight for Samsung boards
  7
  8#include <linux/gpio.h>
  9#include <linux/platform_device.h>
 10#include <linux/slab.h>
 11#include <linux/io.h>
 12#include <linux/pwm_backlight.h>
 13
 14#include "devs.h"
 15#include "gpio-cfg.h"
 16
 17#include "backlight-s3c64xx.h"
 18
 19struct samsung_bl_drvdata {
 20	struct platform_pwm_backlight_data plat_data;
 21	struct samsung_bl_gpio_info *gpio_info;
 22};
 23
 24static int samsung_bl_init(struct device *dev)
 25{
 26	int ret = 0;
 27	struct platform_pwm_backlight_data *pdata = dev->platform_data;
 28	struct samsung_bl_drvdata *drvdata = container_of(pdata,
 29					struct samsung_bl_drvdata, plat_data);
 30	struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
 31
 32	ret = gpio_request(bl_gpio_info->no, "Backlight");
 33	if (ret) {
 34		printk(KERN_ERR "failed to request GPIO for LCD Backlight\n");
 35		return ret;
 36	}
 37
 38	/* Configure GPIO pin with specific GPIO function for PWM timer */
 39	s3c_gpio_cfgpin(bl_gpio_info->no, bl_gpio_info->func);
 40
 41	return 0;
 42}
 43
 44static void samsung_bl_exit(struct device *dev)
 45{
 46	struct platform_pwm_backlight_data *pdata = dev->platform_data;
 47	struct samsung_bl_drvdata *drvdata = container_of(pdata,
 48					struct samsung_bl_drvdata, plat_data);
 49	struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
 50
 51	s3c_gpio_cfgpin(bl_gpio_info->no, S3C_GPIO_OUTPUT);
 52	gpio_free(bl_gpio_info->no);
 53}
 54
 55/* Initialize few important fields of platform_pwm_backlight_data
 56 * structure with default values. These fields can be overridden by
 57 * board-specific values sent from machine file.
 58 * For ease of operation, these fields are initialized with values
 59 * used by most samsung boards.
 60 * Users has the option of sending info about other parameters
 61 * for their specific boards
 62 */
 63
 64static struct samsung_bl_drvdata samsung_dfl_bl_data __initdata = {
 65	.plat_data = {
 66		.max_brightness = 255,
 67		.dft_brightness = 255,
 68		.init           = samsung_bl_init,
 69		.exit           = samsung_bl_exit,
 70	},
 71};
 72
 73static struct platform_device samsung_dfl_bl_device __initdata = {
 74	.name		= "pwm-backlight",
 75};
 76
 77/* samsung_bl_set - Set board specific data (if any) provided by user for
 78 * PWM Backlight control and register specific PWM and backlight device.
 79 * @gpio_info:	structure containing GPIO info for PWM timer
 80 * @bl_data:	structure containing Backlight control data
 81 */
 82void __init samsung_bl_set(struct samsung_bl_gpio_info *gpio_info,
 83	struct platform_pwm_backlight_data *bl_data)
 84{
 85	int ret = 0;
 86	struct platform_device *samsung_bl_device;
 87	struct samsung_bl_drvdata *samsung_bl_drvdata;
 88	struct platform_pwm_backlight_data *samsung_bl_data;
 89
 90	samsung_bl_device = kmemdup(&samsung_dfl_bl_device,
 91			sizeof(struct platform_device), GFP_KERNEL);
 92	if (!samsung_bl_device)
 93		return;
 94
 95	samsung_bl_drvdata = kmemdup(&samsung_dfl_bl_data,
 96				sizeof(samsung_dfl_bl_data), GFP_KERNEL);
 97	if (!samsung_bl_drvdata)
 98		goto err_data;
 99
100	samsung_bl_device->dev.platform_data = &samsung_bl_drvdata->plat_data;
101	samsung_bl_drvdata->gpio_info = gpio_info;
102	samsung_bl_data = &samsung_bl_drvdata->plat_data;
103
104	/* Copy board specific data provided by user */
105	samsung_bl_device->dev.parent = &samsung_device_pwm.dev;
106
107	if (bl_data->max_brightness)
108		samsung_bl_data->max_brightness = bl_data->max_brightness;
109	if (bl_data->dft_brightness)
110		samsung_bl_data->dft_brightness = bl_data->dft_brightness;
111	if (bl_data->lth_brightness)
112		samsung_bl_data->lth_brightness = bl_data->lth_brightness;
113	if (bl_data->init)
114		samsung_bl_data->init = bl_data->init;
115	if (bl_data->notify)
116		samsung_bl_data->notify = bl_data->notify;
117	if (bl_data->notify_after)
118		samsung_bl_data->notify_after = bl_data->notify_after;
119	if (bl_data->exit)
120		samsung_bl_data->exit = bl_data->exit;
121	if (bl_data->check_fb)
122		samsung_bl_data->check_fb = bl_data->check_fb;
123
124	/* Register the Backlight dev */
125	ret = platform_device_register(samsung_bl_device);
126	if (ret) {
127		printk(KERN_ERR "failed to register backlight device: %d\n", ret);
128		goto err_plat_reg2;
129	}
130
131	return;
132
133err_plat_reg2:
134	kfree(samsung_bl_data);
135err_data:
136	kfree(samsung_bl_device);
137}