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/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_powermode = FB_BLANK_UNBLANK; 29 static int current_intensity = 0; 30 static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED; 31 32 static void hp680bl_send_intensity(int intensity) 33 { 34 unsigned long flags; 35 36 if (hp680bl_powermode != FB_BLANK_UNBLANK) 37 intensity = 0; 38 39 spin_lock_irqsave(&bl_lock, flags); 40 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 41 spin_unlock_irqrestore(&bl_lock, flags); 42 } 43 44 static void hp680bl_blank(int blank) 45 { 46 u16 v; 47 48 switch(blank) { 49 50 case FB_BLANK_NORMAL: 51 case FB_BLANK_VSYNC_SUSPEND: 52 case FB_BLANK_HSYNC_SUSPEND: 53 case FB_BLANK_POWERDOWN: 54 if (hp680bl_powermode == FB_BLANK_UNBLANK) { 55 hp680bl_send_intensity(0); 56 hp680bl_powermode = blank; 57 sh_dac_disable(DAC_LCD_BRIGHTNESS); 58 v = inw(HD64461_GPBDR); 59 v |= HD64461_GPBDR_LCDOFF; 60 outw(v, HD64461_GPBDR); 61 } 62 break; 63 case FB_BLANK_UNBLANK: 64 if (hp680bl_powermode != FB_BLANK_UNBLANK) { 65 sh_dac_enable(DAC_LCD_BRIGHTNESS); 66 v = inw(HD64461_GPBDR); 67 v &= ~HD64461_GPBDR_LCDOFF; 68 outw(v, HD64461_GPBDR); 69 hp680bl_powermode = blank; 70 hp680bl_send_intensity(current_intensity); 71 } 72 break; 73 } 74 } 75 76 #ifdef CONFIG_PM 77 static int hp680bl_suspend(struct device *dev, pm_message_t state, u32 level) 78 { 79 if (level == SUSPEND_POWER_DOWN) 80 hp680bl_blank(FB_BLANK_POWERDOWN); 81 return 0; 82 } 83 84 static int hp680bl_resume(struct device *dev, u32 level) 85 { 86 if (level == RESUME_POWER_ON) 87 hp680bl_blank(FB_BLANK_UNBLANK); 88 return 0; 89 } 90 #else 91 #define hp680bl_suspend NULL 92 #define hp680bl_resume NULL 93 #endif 94 95 96 static int hp680bl_set_power(struct backlight_device *bd, int state) 97 { 98 hp680bl_blank(state); 99 return 0; 100 } 101 102 static int hp680bl_get_power(struct backlight_device *bd) 103 { 104 return hp680bl_powermode; 105 } 106 107 static int hp680bl_set_intensity(struct backlight_device *bd, int intensity) 108 { 109 if (intensity > HP680_MAX_INTENSITY) 110 intensity = HP680_MAX_INTENSITY; 111 hp680bl_send_intensity(intensity); 112 current_intensity = intensity; 113 return 0; 114 } 115 116 static int hp680bl_get_intensity(struct backlight_device *bd) 117 { 118 return current_intensity; 119 } 120 121 static struct backlight_properties hp680bl_data = { 122 .owner = THIS_MODULE, 123 .get_power = hp680bl_get_power, 124 .set_power = hp680bl_set_power, 125 .max_brightness = HP680_MAX_INTENSITY, 126 .get_brightness = hp680bl_get_intensity, 127 .set_brightness = hp680bl_set_intensity, 128 }; 129 130 static struct backlight_device *hp680_backlight_device; 131 132 static int __init hp680bl_probe(struct device *dev) 133 { 134 hp680_backlight_device = backlight_device_register ("hp680-bl", 135 NULL, &hp680bl_data); 136 if (IS_ERR (hp680_backlight_device)) 137 return PTR_ERR (hp680_backlight_device); 138 139 hp680bl_set_intensity(NULL, HP680_DEFAULT_INTENSITY); 140 141 return 0; 142 } 143 144 static int hp680bl_remove(struct device *dev) 145 { 146 backlight_device_unregister(hp680_backlight_device); 147 148 return 0; 149 } 150 151 static struct device_driver hp680bl_driver = { 152 .name = "hp680-bl", 153 .bus = &platform_bus_type, 154 .probe = hp680bl_probe, 155 .remove = hp680bl_remove, 156 .suspend = hp680bl_suspend, 157 .resume = hp680bl_resume, 158 }; 159 160 static struct platform_device hp680bl_device = { 161 .name = "hp680-bl", 162 .id = -1, 163 }; 164 165 static int __init hp680bl_init(void) 166 { 167 int ret; 168 169 ret=driver_register(&hp680bl_driver); 170 if (!ret) { 171 ret = platform_device_register(&hp680bl_device); 172 if (ret) 173 driver_unregister(&hp680bl_driver); 174 } 175 return ret; 176 } 177 178 static void __exit hp680bl_exit(void) 179 { 180 platform_device_unregister(&hp680bl_device); 181 driver_unregister(&hp680bl_driver); 182 } 183 184 module_init(hp680bl_init); 185 module_exit(hp680bl_exit); 186 187 MODULE_AUTHOR("Andriy Skulysh <askulysh@image.kiev.ua>"); 188 MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver"); 189 MODULE_LICENSE("GPL"); 190