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.h> 23#include <asm/hd64461.h> 24 25#define HP680_MAX_INTENSITY 255 26#define HP680_DEFAULT_INTENSITY 10 27 28static int hp680bl_suspended; 29static int current_intensity = 0; 30static DEFINE_SPINLOCK(bl_lock); 31 32static void hp680bl_send_intensity(struct backlight_device *bd) 33{ 34 unsigned long flags; 35 u16 v; 36 int intensity = bd->props.brightness; 37 38 if (bd->props.power != FB_BLANK_UNBLANK) 39 intensity = 0; 40 if (bd->props.fb_blank != FB_BLANK_UNBLANK) 41 intensity = 0; 42 if (hp680bl_suspended) 43 intensity = 0; 44 45 spin_lock_irqsave(&bl_lock, flags); 46 if (intensity && current_intensity == 0) { 47 sh_dac_enable(DAC_LCD_BRIGHTNESS); 48 v = inw(HD64461_GPBDR); 49 v &= ~HD64461_GPBDR_LCDOFF; 50 outw(v, HD64461_GPBDR); 51 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 52 } else if (intensity == 0 && current_intensity != 0) { 53 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 54 sh_dac_disable(DAC_LCD_BRIGHTNESS); 55 v = inw(HD64461_GPBDR); 56 v |= HD64461_GPBDR_LCDOFF; 57 outw(v, HD64461_GPBDR); 58 } else if (intensity) { 59 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS); 60 } 61 spin_unlock_irqrestore(&bl_lock, flags); 62 63 current_intensity = intensity; 64} 65 66 67#ifdef CONFIG_PM 68static int hp680bl_suspend(struct platform_device *pdev, pm_message_t state) 69{ 70 struct backlight_device *bd = platform_get_drvdata(pdev); 71 72 hp680bl_suspended = 1; 73 hp680bl_send_intensity(bd); 74 return 0; 75} 76 77static int hp680bl_resume(struct platform_device *pdev) 78{ 79 struct backlight_device *bd = platform_get_drvdata(pdev); 80 81 hp680bl_suspended = 0; 82 hp680bl_send_intensity(bd); 83 return 0; 84} 85#else 86#define hp680bl_suspend NULL 87#define hp680bl_resume NULL 88#endif 89 90static int hp680bl_set_intensity(struct backlight_device *bd) 91{ 92 hp680bl_send_intensity(bd); 93 return 0; 94} 95 96static int hp680bl_get_intensity(struct backlight_device *bd) 97{ 98 return current_intensity; 99} 100 101static struct backlight_ops hp680bl_ops = { 102 .get_brightness = hp680bl_get_intensity, 103 .update_status = hp680bl_set_intensity, 104}; 105 106static int __init hp680bl_probe(struct platform_device *pdev) 107{ 108 struct backlight_device *bd; 109 110 bd = backlight_device_register ("hp680-bl", &pdev->dev, NULL, 111 &hp680bl_ops); 112 if (IS_ERR(bd)) 113 return PTR_ERR(bd); 114 115 platform_set_drvdata(pdev, bd); 116 117 bd->props.max_brightness = HP680_MAX_INTENSITY; 118 bd->props.brightness = HP680_DEFAULT_INTENSITY; 119 hp680bl_send_intensity(bd); 120 121 return 0; 122} 123 124static int hp680bl_remove(struct platform_device *pdev) 125{ 126 struct backlight_device *bd = platform_get_drvdata(pdev); 127 128 hp680bl_data.brightness = 0; 129 hp680bl_data.power = 0; 130 hp680bl_send_intensity(bd); 131 132 backlight_device_unregister(bd); 133 134 return 0; 135} 136 137static struct platform_driver hp680bl_driver = { 138 .probe = hp680bl_probe, 139 .remove = hp680bl_remove, 140 .suspend = hp680bl_suspend, 141 .resume = hp680bl_resume, 142 .driver = { 143 .name = "hp680-bl", 144 }, 145}; 146 147static struct platform_device *hp680bl_device; 148 149static int __init hp680bl_init(void) 150{ 151 int ret; 152 153 ret = platform_driver_register(&hp680bl_driver); 154 if (!ret) { 155 hp680bl_device = platform_device_alloc("hp680-bl", -1); 156 if (!hp680bl_device) 157 return -ENOMEM; 158 159 ret = platform_device_add(hp680bl_device); 160 161 if (ret) { 162 platform_device_put(hp680bl_device); 163 platform_driver_unregister(&hp680bl_driver); 164 } 165 } 166 return ret; 167} 168 169static void __exit hp680bl_exit(void) 170{ 171 platform_device_unregister(hp680bl_device); 172 platform_driver_unregister(&hp680bl_driver); 173} 174 175module_init(hp680bl_init); 176module_exit(hp680bl_exit); 177 178MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>"); 179MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver"); 180MODULE_LICENSE("GPL"); 181