1 // SPDX-License-Identifier: GPL-2.0-only 2 /* drivers/video/backlight/platform_lcd.c 3 * 4 * Copyright 2008 Simtec Electronics 5 * 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 19 struct 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 28 static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd) 29 { 30 return lcd_get_data(lcd); 31 } 32 33 static 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 40 static 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 54 static 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 65 static 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 71 static 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_SLEEP 111 static 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 } 120 121 static 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 #endif 131 132 static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend, 133 platform_lcd_resume); 134 135 static 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 }; 142 143 module_platform_driver(platform_lcd_driver); 144 145 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>"); 146 MODULE_DESCRIPTION("Generic platform-device LCD power control interface"); 147 MODULE_LICENSE("GPL v2"); 148 MODULE_ALIAS("platform:platform-lcd"); 149