1 /* 2 * Backlight Driver for HP Jornada 680 3 * 4 * Copyright (c) 2005 Andriy Skulysh 5 * 6 * Based on Sharp's Corgi Backlight Driver 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file "COPYING" in the main directory of this archive 10 * for more details. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/kernel.h> 15 #include <linux/init.h> 16 #include <linux/platform_device.h> 17 #include <linux/spinlock.h> 18 #include <linux/fb.h> 19 #include <linux/backlight.h> 20 21 #include <cpu/dac.h> 22 #include <mach/hp6xx.h> 23 #include <asm/hd64461.h> 24 25 #define HP680_MAX_INTENSITY 255 26 #define HP680_DEFAULT_INTENSITY 10 27 28 static int hp680bl_suspended; 29 static int current_intensity; 30 static DEFINE_SPINLOCK(bl_lock); 31 32 static void hp680bl_send_intensity(struct backlight_device *bd) 33 { 34 unsigned long flags; 35 u16 v; 36 int intensity = backlight_get_brightness(bd); 37 38 if (hp680bl_suspended) 39 intensity = 0; 40 41 spin_lock_irqsave(&bl_lock, flags); 42 if (intensity && current_intensity == 0) { 43 sh_dac_enable(DAC_LCD_BRIGHTNESS); 44 v = inw(HD64461_GPBDR); 45 v &= ~HD64461_GPBDR_LCDOFF; 46 outw(v, HD64461_GPBDR); 47 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 48 } else if (intensity == 0 && current_intensity != 0) { 49 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 50 sh_dac_disable(DAC_LCD_BRIGHTNESS); 51 v = inw(HD64461_GPBDR); 52 v |= HD64461_GPBDR_LCDOFF; 53 outw(v, HD64461_GPBDR); 54 } else if (intensity) { 55 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 56 } 57 spin_unlock_irqrestore(&bl_lock, flags); 58 59 current_intensity = intensity; 60 } 61 62 63 #ifdef CONFIG_PM_SLEEP 64 static int hp680bl_suspend(struct device *dev) 65 { 66 struct backlight_device *bd = dev_get_drvdata(dev); 67 68 hp680bl_suspended = 1; 69 hp680bl_send_intensity(bd); 70 return 0; 71 } 72 73 static int hp680bl_resume(struct device *dev) 74 { 75 struct backlight_device *bd = dev_get_drvdata(dev); 76 77 hp680bl_suspended = 0; 78 hp680bl_send_intensity(bd); 79 return 0; 80 } 81 #endif 82 83 static SIMPLE_DEV_PM_OPS(hp680bl_pm_ops, hp680bl_suspend, hp680bl_resume); 84 85 static int hp680bl_set_intensity(struct backlight_device *bd) 86 { 87 hp680bl_send_intensity(bd); 88 return 0; 89 } 90 91 static int hp680bl_get_intensity(struct backlight_device *bd) 92 { 93 return current_intensity; 94 } 95 96 static const struct backlight_ops hp680bl_ops = { 97 .get_brightness = hp680bl_get_intensity, 98 .update_status = hp680bl_set_intensity, 99 }; 100 101 static int hp680bl_probe(struct platform_device *pdev) 102 { 103 struct backlight_properties props; 104 struct backlight_device *bd; 105 106 memset(&props, 0, sizeof(struct backlight_properties)); 107 props.type = BACKLIGHT_RAW; 108 props.max_brightness = HP680_MAX_INTENSITY; 109 bd = devm_backlight_device_register(&pdev->dev, "hp680-bl", &pdev->dev, 110 NULL, &hp680bl_ops, &props); 111 if (IS_ERR(bd)) 112 return PTR_ERR(bd); 113 114 platform_set_drvdata(pdev, bd); 115 116 bd->props.brightness = HP680_DEFAULT_INTENSITY; 117 hp680bl_send_intensity(bd); 118 119 return 0; 120 } 121 122 static void hp680bl_remove(struct platform_device *pdev) 123 { 124 struct backlight_device *bd = platform_get_drvdata(pdev); 125 126 bd->props.brightness = 0; 127 bd->props.power = 0; 128 hp680bl_send_intensity(bd); 129 } 130 131 static struct platform_driver hp680bl_driver = { 132 .probe = hp680bl_probe, 133 .remove_new = hp680bl_remove, 134 .driver = { 135 .name = "hp680-bl", 136 .pm = &hp680bl_pm_ops, 137 }, 138 }; 139 140 static struct platform_device *hp680bl_device; 141 142 static int __init hp680bl_init(void) 143 { 144 int ret; 145 146 ret = platform_driver_register(&hp680bl_driver); 147 if (ret) 148 return ret; 149 hp680bl_device = platform_device_register_simple("hp680-bl", -1, 150 NULL, 0); 151 if (IS_ERR(hp680bl_device)) { 152 platform_driver_unregister(&hp680bl_driver); 153 return PTR_ERR(hp680bl_device); 154 } 155 return 0; 156 } 157 158 static void __exit hp680bl_exit(void) 159 { 160 platform_device_unregister(hp680bl_device); 161 platform_driver_unregister(&hp680bl_driver); 162 } 163 164 module_init(hp680bl_init); 165 module_exit(hp680bl_exit); 166 167 MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>"); 168 MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver"); 169 MODULE_LICENSE("GPL"); 170