Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linux
[linux-2.6] / drivers / video / backlight / mbp_nvidia_bl.c
1 /*
2  *  Backlight Driver for Nvidia 8600 in Macbook Pro
3  *
4  *  Copyright (c) Red Hat <mjg@redhat.com>
5  *  Based on code from Pommed:
6  *  Copyright (C) 2006 Nicolas Boichat <nicolas @boichat.ch>
7  *  Copyright (C) 2006 Felipe Alfaro Solana <felipe_alfaro @linuxmail.org>
8  *  Copyright (C) 2007 Julien BLACHE <jb@jblache.org>
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License version 2 as
12  *  published by the Free Software Foundation.
13  *
14  *  This driver triggers SMIs which cause the firmware to change the
15  *  backlight brightness. This is icky in many ways, but it's impractical to
16  *  get at the firmware code in order to figure out what it's actually doing.
17  */
18
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/backlight.h>
24 #include <linux/err.h>
25 #include <linux/dmi.h>
26 #include <linux/io.h>
27
28 static struct backlight_device *mbp_backlight_device;
29
30 /* Structure to be passed to the DMI_MATCH function. */
31 struct dmi_match_data {
32         /* I/O resource to allocate. */
33         unsigned long iostart;
34         unsigned long iolen;
35         /* Backlight operations structure. */
36         struct backlight_ops backlight_ops;
37 };
38
39 /* Module parameters. */
40 static int debug;
41 module_param_named(debug, debug, int, 0644);
42 MODULE_PARM_DESC(debug, "Set to one to enable debugging messages.");
43
44 /*
45  * Implementation for MacBooks with Intel chipset.
46  */
47 static int intel_chipset_send_intensity(struct backlight_device *bd)
48 {
49         int intensity = bd->props.brightness;
50
51         if (debug)
52                 printk(KERN_DEBUG "mbp_nvidia_bl: setting brightness to %d\n",
53                        intensity);
54
55         outb(0x04 | (intensity << 4), 0xb3);
56         outb(0xbf, 0xb2);
57         return 0;
58 }
59
60 static int intel_chipset_get_intensity(struct backlight_device *bd)
61 {
62         int intensity;
63
64         outb(0x03, 0xb3);
65         outb(0xbf, 0xb2);
66         intensity = inb(0xb3) >> 4;
67
68         if (debug)
69                 printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
70                        intensity);
71
72         return intensity;
73 }
74
75 static const struct dmi_match_data intel_chipset_data = {
76         .iostart = 0xb2,
77         .iolen = 2,
78         .backlight_ops  = {
79                 .options        = BL_CORE_SUSPENDRESUME,
80                 .get_brightness = intel_chipset_get_intensity,
81                 .update_status  = intel_chipset_send_intensity,
82         }
83 };
84
85 /*
86  * Implementation for MacBooks with Nvidia chipset.
87  */
88 static int nvidia_chipset_send_intensity(struct backlight_device *bd)
89 {
90         int intensity = bd->props.brightness;
91
92         if (debug)
93                 printk(KERN_DEBUG "mbp_nvidia_bl: setting brightness to %d\n",
94                        intensity);
95
96         outb(0x04 | (intensity << 4), 0x52f);
97         outb(0xbf, 0x52e);
98         return 0;
99 }
100
101 static int nvidia_chipset_get_intensity(struct backlight_device *bd)
102 {
103         int intensity;
104
105         outb(0x03, 0x52f);
106         outb(0xbf, 0x52e);
107         intensity = inb(0x52f) >> 4;
108
109         if (debug)
110                 printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
111                        intensity);
112
113         return intensity;
114 }
115
116 static const struct dmi_match_data nvidia_chipset_data = {
117         .iostart = 0x52e,
118         .iolen = 2,
119         .backlight_ops          = {
120                 .options        = BL_CORE_SUSPENDRESUME,
121                 .get_brightness = nvidia_chipset_get_intensity,
122                 .update_status  = nvidia_chipset_send_intensity
123         }
124 };
125
126 /*
127  * DMI matching.
128  */
129 static /* const */ struct dmi_match_data *driver_data;
130
131 static int mbp_dmi_match(const struct dmi_system_id *id)
132 {
133         driver_data = id->driver_data;
134
135         printk(KERN_INFO "mbp_nvidia_bl: %s detected\n", id->ident);
136         return 1;
137 }
138
139 static const struct dmi_system_id __initdata mbp_device_table[] = {
140         {
141                 .callback       = mbp_dmi_match,
142                 .ident          = "MacBookPro 3,1",
143                 .matches        = {
144                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
145                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro3,1"),
146                 },
147                 .driver_data    = (void *)&intel_chipset_data,
148         },
149         {
150                 .callback       = mbp_dmi_match,
151                 .ident          = "MacBookPro 3,2",
152                 .matches        = {
153                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
154                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro3,2"),
155                 },
156                 .driver_data    = (void *)&intel_chipset_data,
157         },
158         {
159                 .callback       = mbp_dmi_match,
160                 .ident          = "MacBookPro 4,1",
161                 .matches        = {
162                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
163                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro4,1"),
164                 },
165                 .driver_data    = (void *)&intel_chipset_data,
166         },
167         {
168                 .callback       = mbp_dmi_match,
169                 .ident          = "MacBook 5,1",
170                 .matches        = {
171                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
172                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5,1"),
173                 },
174                 .driver_data    = (void *)&nvidia_chipset_data,
175         },
176         {
177                 .callback       = mbp_dmi_match,
178                 .ident          = "MacBookAir 2,1",
179                 .matches        = {
180                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
181                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir2,1"),
182                 },
183                 .driver_data    = (void *)&nvidia_chipset_data,
184         },
185         {
186                 .callback       = mbp_dmi_match,
187                 .ident          = "MacBookPro 5,1",
188                 .matches        = {
189                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
190                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,1"),
191                 },
192                 .driver_data    = (void *)&nvidia_chipset_data,
193         },
194         { }
195 };
196
197 static int __init mbp_init(void)
198 {
199         if (!dmi_check_system(mbp_device_table))
200                 return -ENODEV;
201
202         if (!request_region(driver_data->iostart, driver_data->iolen, 
203                                                 "Macbook Pro backlight"))
204                 return -ENXIO;
205
206         mbp_backlight_device = backlight_device_register("mbp_backlight",
207                                         NULL, NULL, &driver_data->backlight_ops);
208         if (IS_ERR(mbp_backlight_device)) {
209                 release_region(driver_data->iostart, driver_data->iolen);
210                 return PTR_ERR(mbp_backlight_device);
211         }
212
213         mbp_backlight_device->props.max_brightness = 15;
214         mbp_backlight_device->props.brightness =
215                 driver_data->backlight_ops.get_brightness(mbp_backlight_device);
216         backlight_update_status(mbp_backlight_device);
217
218         return 0;
219 }
220
221 static void __exit mbp_exit(void)
222 {
223         backlight_device_unregister(mbp_backlight_device);
224
225         release_region(driver_data->iostart, driver_data->iolen);
226 }
227
228 module_init(mbp_init);
229 module_exit(mbp_exit);
230
231 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
232 MODULE_DESCRIPTION("Nvidia-based Macbook Pro Backlight Driver");
233 MODULE_LICENSE("GPL");
234 MODULE_DEVICE_TABLE(dmi, mbp_device_table);