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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  19
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/mutex.h>
  25 #include <linux/fb.h>
  26 #include <linux/backlight.h>
  27 #include <linux/pci.h>
  28
  29 #define PMU_LPCR               0xB0
  30 #define SB_MPS1                0x61
  31 #define HW_LEVEL_MAX           0x77
  32 #define HW_LEVEL_MIN           0x4f
  33
  34 static struct pci_dev *pmu_dev = NULL;
  35 static struct pci_dev *sb_dev = NULL;
  36
  37 static int progearbl_set_intensity(struct backlight_device *bd)
  38 {
  39         int intensity = bd->props.brightness;
  40
  41         if (bd->props.power != FB_BLANK_UNBLANK)
  42                 intensity = 0;
  43         if (bd->props.fb_blank != FB_BLANK_UNBLANK)
  44                 intensity = 0;
  45
  46         pci_write_config_byte(pmu_dev, PMU_LPCR, intensity + HW_LEVEL_MIN);
  47
  48         return 0;
  49 }
  50
  51 static int progearbl_get_intensity(struct backlight_device *bd)
  52 {
  53         u8 intensity;
  54         pci_read_config_byte(pmu_dev, PMU_LPCR, &intensity);
  55
  56         return intensity - HW_LEVEL_MIN;
  57 }
  58
  59 static const struct backlight_ops progearbl_ops = {
  60         .get_brightness = progearbl_get_intensity,
  61         .update_status = progearbl_set_intensity,
  62 };
  63
  64 static int progearbl_probe(struct platform_device *pdev)
  65 {
  66         struct backlight_properties props;
  67         u8 temp;
  68         struct backlight_device *progear_backlight_device;
  69         int ret;
  70
  71         pmu_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101, NULL);
  72         if (!pmu_dev) {
  73                 pr_err("ALI M7101 PMU not found.\n");
  74                 return -ENODEV;
  75         }
  76
  77         sb_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
  78         if (!sb_dev) {
  79                 pr_err("ALI 1533 SB not found.\n");
  80                 ret = -ENODEV;
  81                 goto put_pmu;
  82         }
  83
  84         /*     Set SB_MPS1 to enable brightness control. */
  85         pci_read_config_byte(sb_dev, SB_MPS1, &temp);
  86         pci_write_config_byte(sb_dev, SB_MPS1, temp | 0x20);
  87
  88         memset(&props, 0, sizeof(struct backlight_properties));
  89         props.type = BACKLIGHT_RAW;
  90         props.max_brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
  91         progear_backlight_device = backlight_device_register("progear-bl",
  92                                                              &pdev->dev, NULL,
  93                                                              &progearbl_ops,
  94                                                              &props);
  95         if (IS_ERR(progear_backlight_device)) {
  96                 ret = PTR_ERR(progear_backlight_device);
  97                 goto put_sb;
  98         }
  99
 100         platform_set_drvdata(pdev, progear_backlight_device);
 101
 102         progear_backlight_device->props.power = FB_BLANK_UNBLANK;
 103         progear_backlight_device->props.brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
 104         progearbl_set_intensity(progear_backlight_device);
 105
 106         return 0;
 107 put_sb:
 108         pci_dev_put(sb_dev);
 109 put_pmu:
 110         pci_dev_put(pmu_dev);
 111         return ret;
 112 }
 113
 114 static int progearbl_remove(struct platform_device *pdev)
 115 {
 116         struct backlight_device *bd = platform_get_drvdata(pdev);
 117         backlight_device_unregister(bd);
 118
 119         return 0;
 120 }
 121
 122 static struct platform_driver progearbl_driver = {
 123         .probe = progearbl_probe,
 124         .remove = progearbl_remove,
 125         .driver = {
 126                    .name = "progear-bl",
 127                    },
 128 };
 129
 130 static struct platform_device *progearbl_device;
 131
 132 static int __init progearbl_init(void)
 133 {
 134         int ret = platform_driver_register(&progearbl_driver);
 135
 136         if (ret)
 137                 return ret;
 138         progearbl_device = platform_device_register_simple("progear-bl", -1,
 139                                                                 NULL, 0);
 140         if (IS_ERR(progearbl_device)) {
 141                 platform_driver_unregister(&progearbl_driver);
 142                 return PTR_ERR(progearbl_device);
 143         }
 144
 145         return 0;
 146 }
 147
 148 static void __exit progearbl_exit(void)
 149 {
 150         pci_dev_put(pmu_dev);
 151         pci_dev_put(sb_dev);
 152
 153         platform_device_unregister(progearbl_device);
 154         platform_driver_unregister(&progearbl_driver);
 155 }
 156
 157 module_init(progearbl_init);
 158 module_exit(progearbl_exit);
 159
 160 MODULE_AUTHOR("Marcin Juszkiewicz <linux@hrw.one.pl>");
 161 MODULE_DESCRIPTION("ProGear Backlight Driver");
 162 MODULE_LICENSE("GPL");