149 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/* drivers/video/backlight/platform_lcd.c3 *4 * Copyright 2008 Simtec Electronics5 * Ben Dooks <ben@simtec.co.uk>6 *7 * Generic platform-device LCD power control interface.8*/9 10#include <linux/module.h>11#include <linux/platform_device.h>12#include <linux/fb.h>13#include <linux/backlight.h>14#include <linux/lcd.h>15#include <linux/slab.h>16 17#include <video/platform_lcd.h>18 19struct platform_lcd {20 struct device *us;21 struct lcd_device *lcd;22 struct plat_lcd_data *pdata;23 24 unsigned int power;25 unsigned int suspended:1;26};27 28static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd)29{30 return lcd_get_data(lcd);31}32 33static int platform_lcd_get_power(struct lcd_device *lcd)34{35 struct platform_lcd *plcd = to_our_lcd(lcd);36 37 return plcd->power;38}39 40static int platform_lcd_set_power(struct lcd_device *lcd, int power)41{42 struct platform_lcd *plcd = to_our_lcd(lcd);43 int lcd_power = 1;44 45 if (power == FB_BLANK_POWERDOWN || plcd->suspended)46 lcd_power = 0;47 48 plcd->pdata->set_power(plcd->pdata, lcd_power);49 plcd->power = power;50 51 return 0;52}53 54static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info)55{56 struct platform_lcd *plcd = to_our_lcd(lcd);57 struct plat_lcd_data *pdata = plcd->pdata;58 59 if (pdata->match_fb)60 return pdata->match_fb(pdata, info);61 62 return plcd->us->parent == info->device;63}64 65static const struct lcd_ops platform_lcd_ops = {66 .get_power = platform_lcd_get_power,67 .set_power = platform_lcd_set_power,68 .check_fb = platform_lcd_match,69};70 71static int platform_lcd_probe(struct platform_device *pdev)72{73 struct plat_lcd_data *pdata;74 struct platform_lcd *plcd;75 struct device *dev = &pdev->dev;76 int err;77 78 pdata = dev_get_platdata(&pdev->dev);79 if (!pdata) {80 dev_err(dev, "no platform data supplied\n");81 return -EINVAL;82 }83 84 if (pdata->probe) {85 err = pdata->probe(pdata);86 if (err)87 return err;88 }89 90 plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd),91 GFP_KERNEL);92 if (!plcd)93 return -ENOMEM;94 95 plcd->us = dev;96 plcd->pdata = pdata;97 plcd->lcd = devm_lcd_device_register(&pdev->dev, dev_name(dev), dev,98 plcd, &platform_lcd_ops);99 if (IS_ERR(plcd->lcd)) {100 dev_err(dev, "cannot register lcd device\n");101 return PTR_ERR(plcd->lcd);102 }103 104 platform_set_drvdata(pdev, plcd);105 platform_lcd_set_power(plcd->lcd, FB_BLANK_NORMAL);106 107 return 0;108}109 110#ifdef CONFIG_PM_SLEEP111static int platform_lcd_suspend(struct device *dev)112{113 struct platform_lcd *plcd = dev_get_drvdata(dev);114 115 plcd->suspended = 1;116 platform_lcd_set_power(plcd->lcd, plcd->power);117 118 return 0;119}120 121static int platform_lcd_resume(struct device *dev)122{123 struct platform_lcd *plcd = dev_get_drvdata(dev);124 125 plcd->suspended = 0;126 platform_lcd_set_power(plcd->lcd, plcd->power);127 128 return 0;129}130#endif131 132static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend,133 platform_lcd_resume);134 135static struct platform_driver platform_lcd_driver = {136 .driver = {137 .name = "platform-lcd",138 .pm = &platform_lcd_pm_ops,139 },140 .probe = platform_lcd_probe,141};142 143module_platform_driver(platform_lcd_driver);144 145MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");146MODULE_DESCRIPTION("Generic platform-device LCD power control interface");147MODULE_LICENSE("GPL v2");148MODULE_ALIAS("platform:platform-lcd");149