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
  27 #define PMU_LPCR               0xB0
  28 #define SB_MPS1                0x61
  29 #define HW_LEVEL_MAX           0x77
  30 #define HW_LEVEL_MIN           0x4f
  31
  32 static struct pci_dev *pmu_dev = NULL;
  33 static struct pci_dev *sb_dev = NULL;
  34
  35 static int progearbl_set_intensity(struct backlight_device *bd)
  36 {
  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
  44         pci_write_config_byte(pmu_dev, PMU_LPCR, intensity + HW_LEVEL_MIN);
  45
  46         return 0;
  47 }
  48
  49 static int progearbl_get_intensity(struct backlight_device *bd)
  50 {
  51         u8 intensity;
  52         pci_read_config_byte(pmu_dev, PMU_LPCR, &intensity);
  53
  54         return intensity - HW_LEVEL_MIN;
  55 }
  56
  57 static struct backlight_ops progearbl_ops = {
  58         .get_brightness = progearbl_get_intensity,
  59         .update_status = progearbl_set_intensity,
  60 };
  61
  62 static int progearbl_probe(struct platform_device *pdev)
  63 {
  64         u8 temp;
  65         struct backlight_device *progear_backlight_device;
  66
  67         pmu_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101, NULL);
  68         if (!pmu_dev) {
  69                 printk("ALI M7101 PMU not found.\n");
  70                 return -ENODEV;
  71         }
  72
  73         sb_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
  74         if (!sb_dev) {
  75                 printk("ALI 1533 SB not found.\n");
  76                 pci_dev_put(pmu_dev);
  77                 return -ENODEV;
  78         }
  79
  80         /*     Set SB_MPS1 to enable brightness control. */
  81         pci_read_config_byte(sb_dev, SB_MPS1, &temp);
  82         pci_write_config_byte(sb_dev, SB_MPS1, temp | 0x20);
  83
  84         progear_backlight_device = backlight_device_register("progear-bl",
  85                                                              &pdev->dev, NULL,
  86                                                              &progearbl_ops);
  87         if (IS_ERR(progear_backlight_device))
  88                 return PTR_ERR(progear_backlight_device);
  89
  90         platform_set_drvdata(pdev, progear_backlight_device);
  91
  92         progear_backlight_device->props.power = FB_BLANK_UNBLANK;
  93         progear_backlight_device->props.brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
  94         progear_backlight_device->props.max_brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
  95         progearbl_set_intensity(progear_backlight_device);
  96
  97         return 0;
  98 }
  99
 100 static int progearbl_remove(struct platform_device *pdev)
 101 {
 102         struct backlight_device *bd = platform_get_drvdata(pdev);
 103         backlight_device_unregister(bd);
 104
 105         return 0;
 106 }
 107
 108 static struct platform_driver progearbl_driver = {
 109         .probe = progearbl_probe,
 110         .remove = progearbl_remove,
 111         .driver = {
 112                    .name = "progear-bl",
 113                    },
 114 };
 115
 116 static struct platform_device *progearbl_device;
 117
 118 static int __init progearbl_init(void)
 119 {
 120         int ret = platform_driver_register(&progearbl_driver);
 121
 122         if (!ret) {
 123                 progearbl_device = platform_device_alloc("progear-bl", -1);
 124                 if (!progearbl_device)
 125                         return -ENOMEM;
 126
 127                 ret = platform_device_add(progearbl_device);
 128
 129                 if (ret) {
 130                         platform_device_put(progearbl_device);
 131                         platform_driver_unregister(&progearbl_driver);
 132                 }
 133         }
 134
 135         return ret;
 136 }
 137
 138 static void __exit progearbl_exit(void)
 139 {
 140         pci_dev_put(pmu_dev);
 141         pci_dev_put(sb_dev);
 142
 143         platform_device_unregister(progearbl_device);
 144         platform_driver_unregister(&progearbl_driver);
 145 }
 146
 147 module_init(progearbl_init);
 148 module_exit(progearbl_exit);
 149
 150 MODULE_AUTHOR("Marcin Juszkiewicz <linux@hrw.one.pl>");
 151 MODULE_DESCRIPTION("ProGear Backlight Driver");
 152 MODULE_LICENSE("GPL");