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 <asm/cpu/dac.h> 22 #include <asm/hp6xx/hp6xx.h> 23 #include <asm/hd64461/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 = 0; 30 static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED; 31 static struct backlight_device *hp680_backlight_device; 32 33 static void hp680bl_send_intensity(struct backlight_device *bd) 34 { 35 unsigned long flags; 36 u16 v; 37 int intensity = bd->props->brightness; 38 39 if (bd->props->power != FB_BLANK_UNBLANK) 40 intensity = 0; 41 if (bd->props->fb_blank != FB_BLANK_UNBLANK) 42 intensity = 0; 43 if (hp680bl_suspended) 44 intensity = 0; 45 46 spin_lock_irqsave(&bl_lock, flags); 47 if (intensity && current_intensity == 0) { 48 sh_dac_enable(DAC_LCD_BRIGHTNESS); 49 v = inw(HD64461_GPBDR); 50 v &= ~HD64461_GPBDR_LCDOFF; 51 outw(v, HD64461_GPBDR); 52 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 53 } else if (intensity == 0 && current_intensity != 0) { 54 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 55 sh_dac_disable(DAC_LCD_BRIGHTNESS); 56 v = inw(HD64461_GPBDR); 57 v |= HD64461_GPBDR_LCDOFF; 58 outw(v, HD64461_GPBDR); 59 } else if (intensity) { 60 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 61 } 62 spin_unlock_irqrestore(&bl_lock, flags); 63 64 current_intensity = intensity; 65 } 66 67 68 #ifdef CONFIG_PM 69 static int hp680bl_suspend(struct platform_device *dev, pm_message_t state) 70 { 71 hp680bl_suspended = 1; 72 hp680bl_send_intensity(hp680_backlight_device); 73 return 0; 74 } 75 76 static int hp680bl_resume(struct platform_device *dev) 77 { 78 hp680bl_suspended = 0; 79 hp680bl_send_intensity(hp680_backlight_device); 80 return 0; 81 } 82 #else 83 #define hp680bl_suspend NULL 84 #define hp680bl_resume NULL 85 #endif 86 87 static int hp680bl_set_intensity(struct backlight_device *bd) 88 { 89 hp680bl_send_intensity(bd); 90 return 0; 91 } 92 93 static int hp680bl_get_intensity(struct backlight_device *bd) 94 { 95 return current_intensity; 96 } 97 98 static struct backlight_properties hp680bl_data = { 99 .owner = THIS_MODULE, 100 .max_brightness = HP680_MAX_INTENSITY, 101 .get_brightness = hp680bl_get_intensity, 102 .update_status = hp680bl_set_intensity, 103 }; 104 105 static int __init hp680bl_probe(struct platform_device *dev) 106 { 107 hp680_backlight_device = backlight_device_register ("hp680-bl", 108 NULL, &hp680bl_data); 109 if (IS_ERR (hp680_backlight_device)) 110 return PTR_ERR (hp680_backlight_device); 111 112 hp680_backlight_device->props->brightness = HP680_DEFAULT_INTENSITY; 113 hp680bl_send_intensity(hp680_backlight_device); 114 115 return 0; 116 } 117 118 static int hp680bl_remove(struct platform_device *dev) 119 { 120 backlight_device_unregister(hp680_backlight_device); 121 122 return 0; 123 } 124 125 static struct platform_driver hp680bl_driver = { 126 .probe = hp680bl_probe, 127 .remove = hp680bl_remove, 128 .suspend = hp680bl_suspend, 129 .resume = hp680bl_resume, 130 .driver = { 131 .name = "hp680-bl", 132 }, 133 }; 134 135 static struct platform_device *hp680bl_device; 136 137 static int __init hp680bl_init(void) 138 { 139 int ret; 140 141 ret = platform_driver_register(&hp680bl_driver); 142 if (!ret) { 143 hp680bl_device = platform_device_alloc("hp680-bl", -1); 144 if (!hp680bl_device) 145 return -ENOMEM; 146 147 ret = platform_device_add(hp680bl_device); 148 149 if (ret) { 150 platform_device_put(hp680bl_device); 151 platform_driver_unregister(&hp680bl_driver); 152 } 153 } 154 return ret; 155 } 156 157 static void __exit hp680bl_exit(void) 158 { 159 platform_device_unregister(hp680bl_device); 160 platform_driver_unregister(&hp680bl_driver); 161 } 162 163 module_init(hp680bl_init); 164 module_exit(hp680bl_exit); 165 166 MODULE_AUTHOR("Andriy Skulysh <askulysh@image.kiev.ua>"); 167 MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver"); 168 MODULE_LICENSE("GPL"); 169