drivers/video/backlight/progear_bl.c

   1 /*
   2  *  Backlight Driver for Frontpath ProGear HX1050+
   3  *
   4  *  Copyright (c) 2006 Marcin Juszkiewicz
   5  *
   6  *  Based on Progear LCD driver by M Schacht
   7  *  <mschacht at alumni dot washington dot edu>
   8  *
   9  *  Based on Sharp's Corgi Backlight Driver
  10  *  Based on Backlight Driver for HP Jornada 680
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License version 2 as
  14  *  published by the Free Software Foundation.
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/init.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/mutex.h>
  23 #include <linux/fb.h>
  24 #include <linux/backlight.h>
  25 #include <linux/pci.h>
  26 #include <asm/uaccess.h>
  27
  28 #define PMU_LPCR               0xB0
  29 #define SB_MPS1                0x61
  30 #define HW_LEVEL_MAX           0x77
  31 #define HW_LEVEL_MIN           0x4f
  32
  33 static struct pci_dev *pmu_dev = NULL;
  34 static struct pci_dev *sb_dev = NULL;
  35
  36 static int progearbl_set_intensity(struct backlight_device *bd)
  37 {
  38         int intensity = bd->props.brightness;
  39
  40         if (bd->props.power != FB_BLANK_UNBLANK)
  41                 intensity = 0;
  42         if (bd->props.fb_blank != FB_BLANK_UNBLANK)
  43                 intensity = 0;
  44
  45         pci_write_config_byte(pmu_dev, PMU_LPCR, intensity + HW_LEVEL_MIN);
  46
  47         return 0;
  48 }
  49
  50 static int progearbl_get_intensity(struct backlight_device *bd)
  51 {
  52         u8 intensity;
  53         pci_read_config_byte(pmu_dev, PMU_LPCR, &intensity);
  54
  55         return intensity - HW_LEVEL_MIN;
  56 }
  57
  58 static struct backlight_ops progearbl_ops = {
  59         .get_brightness = progearbl_get_intensity,
  60         .update_status = progearbl_set_intensity,
  61 };
  62
  63 static int progearbl_probe(struct platform_device *pdev)
  64 {
  65         u8 temp;
  66         struct backlight_device *progear_backlight_device;
  67
  68         pmu_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101, NULL);
  69         if (!pmu_dev) {
  70                 printk("ALI M7101 PMU not found.\n");
  71                 return -ENODEV;
  72         }
  73
  74         sb_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
  75         if (!sb_dev) {
  76                 printk("ALI 1533 SB not found.\n");
  77                 pci_dev_put(pmu_dev);
  78                 return -ENODEV;
  79         }
  80
  81         /*     Set SB_MPS1 to enable brightness control. */
  82         pci_read_config_byte(sb_dev, SB_MPS1, &temp);
  83         pci_write_config_byte(sb_dev, SB_MPS1, temp | 0x20);
  84
  85         progear_backlight_device = backlight_device_register("progear-bl",
  86                                                              &pdev->dev, NULL,
  87                                                              &progearbl_ops);
  88         if (IS_ERR(progear_backlight_device))
  89                 return PTR_ERR(progear_backlight_device);
  90
  91         platform_set_drvdata(pdev, progear_backlight_device);
  92
  93         progear_backlight_device->props.power = FB_BLANK_UNBLANK;
  94         progear_backlight_device->props.brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
  95         progear_backlight_device->props.max_brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
  96         progearbl_set_intensity(progear_backlight_device);
  97
  98         return 0;
  99 }
 100
 101 static int progearbl_remove(struct platform_device *pdev)
 102 {
 103         struct backlight_device *bd = platform_get_drvdata(pdev);
 104         backlight_device_unregister(bd);
 105
 106         return 0;
 107 }
 108
 109 static struct platform_driver progearbl_driver = {
 110         .probe = progearbl_probe,
 111         .remove = progearbl_remove,
 112         .driver = {
 113                    .name = "progear-bl",
 114                    },
 115 };
 116
 117 static struct platform_device *progearbl_device;
 118
 119 static int __init progearbl_init(void)
 120 {
 121         int ret = platform_driver_register(&progearbl_driver);
 122
 123         if (!ret) {
 124                 progearbl_device = platform_device_alloc("progear-bl", -1);
 125                 if (!progearbl_device)
 126                         return -ENOMEM;
 127
 128                 ret = platform_device_add(progearbl_device);
 129
 130                 if (ret) {
 131                         platform_device_put(progearbl_device);
 132                         platform_driver_unregister(&progearbl_driver);
 133                 }
 134         }
 135
 136         return ret;
 137 }
 138
 139 static void __exit progearbl_exit(void)
 140 {
 141         pci_dev_put(pmu_dev);
 142         pci_dev_put(sb_dev);
 143
 144         platform_device_unregister(progearbl_device);
 145         platform_driver_unregister(&progearbl_driver);
 146 }
 147
 148 module_init(progearbl_init);
 149 module_exit(progearbl_exit);
 150
 151 MODULE_AUTHOR("Marcin Juszkiewicz <linux@hrw.one.pl>");
 152 MODULE_DESCRIPTION("ProGear Backlight Driver");
 153 MODULE_LICENSE("GPL");