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/of.h> 16 #include <linux/slab.h> 17 18 #include <video/platform_lcd.h> 19 20 struct platform_lcd { 21 struct device *us; 22 struct lcd_device *lcd; 23 struct plat_lcd_data *pdata; 24 25 unsigned int power; 26 unsigned int suspended:1; 27 }; 28 29 static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd) 30 { 31 return lcd_get_data(lcd); 32 } 33 34 static int platform_lcd_get_power(struct lcd_device *lcd) 35 { 36 struct platform_lcd *plcd = to_our_lcd(lcd); 37 38 return plcd->power; 39 } 40 41 static int platform_lcd_set_power(struct lcd_device *lcd, int power) 42 { 43 struct platform_lcd *plcd = to_our_lcd(lcd); 44 int lcd_power = 1; 45 46 if (power == FB_BLANK_POWERDOWN || plcd->suspended) 47 lcd_power = 0; 48 49 plcd->pdata->set_power(plcd->pdata, lcd_power); 50 plcd->power = power; 51 52 return 0; 53 } 54 55 static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info) 56 { 57 struct platform_lcd *plcd = to_our_lcd(lcd); 58 struct plat_lcd_data *pdata = plcd->pdata; 59 60 if (pdata->match_fb) 61 return pdata->match_fb(pdata, info); 62 63 return plcd->us->parent == info->device; 64 } 65 66 static struct lcd_ops platform_lcd_ops = { 67 .get_power = platform_lcd_get_power, 68 .set_power = platform_lcd_set_power, 69 .check_fb = platform_lcd_match, 70 }; 71 72 static int platform_lcd_probe(struct platform_device *pdev) 73 { 74 struct plat_lcd_data *pdata; 75 struct platform_lcd *plcd; 76 struct device *dev = &pdev->dev; 77 int err; 78 79 pdata = dev_get_platdata(&pdev->dev); 80 if (!pdata) { 81 dev_err(dev, "no platform data supplied\n"); 82 return -EINVAL; 83 } 84 85 if (pdata->probe) { 86 err = pdata->probe(pdata); 87 if (err) 88 return err; 89 } 90 91 plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd), 92 GFP_KERNEL); 93 if (!plcd) 94 return -ENOMEM; 95 96 plcd->us = dev; 97 plcd->pdata = pdata; 98 plcd->lcd = devm_lcd_device_register(&pdev->dev, dev_name(dev), dev, 99 plcd, &platform_lcd_ops); 100 if (IS_ERR(plcd->lcd)) { 101 dev_err(dev, "cannot register lcd device\n"); 102 return PTR_ERR(plcd->lcd); 103 } 104 105 platform_set_drvdata(pdev, plcd); 106 platform_lcd_set_power(plcd->lcd, FB_BLANK_NORMAL); 107 108 return 0; 109 } 110 111 #ifdef CONFIG_PM_SLEEP 112 static int platform_lcd_suspend(struct device *dev) 113 { 114 struct platform_lcd *plcd = dev_get_drvdata(dev); 115 116 plcd->suspended = 1; 117 platform_lcd_set_power(plcd->lcd, plcd->power); 118 119 return 0; 120 } 121 122 static int platform_lcd_resume(struct device *dev) 123 { 124 struct platform_lcd *plcd = dev_get_drvdata(dev); 125 126 plcd->suspended = 0; 127 platform_lcd_set_power(plcd->lcd, plcd->power); 128 129 return 0; 130 } 131 #endif 132 133 static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend, 134 platform_lcd_resume); 135 136 #ifdef CONFIG_OF 137 static const struct of_device_id platform_lcd_of_match[] = { 138 { .compatible = "platform-lcd" }, 139 {}, 140 }; 141 MODULE_DEVICE_TABLE(of, platform_lcd_of_match); 142 #endif 143 144 static struct platform_driver platform_lcd_driver = { 145 .driver = { 146 .name = "platform-lcd", 147 .pm = &platform_lcd_pm_ops, 148 .of_match_table = of_match_ptr(platform_lcd_of_match), 149 }, 150 .probe = platform_lcd_probe, 151 }; 152 153 module_platform_driver(platform_lcd_driver); 154 155 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>"); 156 MODULE_LICENSE("GPL v2"); 157 MODULE_ALIAS("platform:platform-lcd"); 158