ACPI: video: convert to acpi_get_pci_dev
[linux-3.10.git] / drivers / acpi / video_detect.c
1 /*
2  *  Copyright (C) 2008       SuSE Linux Products GmbH
3  *                           Thomas Renninger <trenn@suse.de>
4  *
5  *  May be copied or modified under the terms of the GNU General Public License
6  *
7  * video_detect.c:
8  * Provides acpi_is_video_device() for early scanning of ACPI devices in scan.c
9  * There a Linux specific (Spec does not provide a HID for video devices) is
10  * assinged
11  *
12  * After PCI devices are glued with ACPI devices
13  * acpi_get_pci_dev() can be called to identify ACPI graphics
14  * devices for which a real graphics card is plugged in
15  *
16  * Now acpi_video_get_capabilities() can be called to check which
17  * capabilities the graphics cards plugged in support. The check for general
18  * video capabilities will be triggered by the first caller of
19  * acpi_video_get_capabilities(NULL); which will happen when the first
20  * backlight (or display output) switching supporting driver calls:
21  * acpi_video_backlight_support();
22  *
23  * Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
24  * are available, video.ko should be used to handle the device.
25  *
26  * Otherwise vendor specific drivers like thinkpad_acpi, asus_acpi,
27  * sony_acpi,... can take care about backlight brightness and display output
28  * switching.
29  *
30  * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
31  * this file will not be compiled, acpi_video_get_capabilities() and
32  * acpi_video_backlight_support() will always return 0 and vendor specific
33  * drivers always can handle backlight.
34  *
35  */
36
37 #include <linux/acpi.h>
38 #include <linux/dmi.h>
39 #include <linux/pci.h>
40
41 ACPI_MODULE_NAME("video");
42 #define _COMPONENT              ACPI_VIDEO_COMPONENT
43
44 static long acpi_video_support;
45 static bool acpi_video_caps_checked;
46
47 static acpi_status
48 acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
49                           void **retyurn_value)
50 {
51         long *cap = context;
52         acpi_handle h_dummy;
53
54         if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) &&
55             ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) {
56                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
57                                   "support\n"));
58                 *cap |= ACPI_VIDEO_BACKLIGHT;
59                 if (ACPI_FAILURE(acpi_get_handle(handle, "_BQC", &h_dummy)))
60                         printk(KERN_WARNING FW_BUG PREFIX "ACPI brightness "
61                                         "control misses _BQC function\n");
62                 /* We have backlight support, no need to scan further */
63                 return AE_CTRL_TERMINATE;
64         }
65         return 0;
66 }
67
68 /* Returns true if the device is a video device which can be handled by
69  * video.ko.
70  * The device will get a Linux specific CID added in scan.c to
71  * identify the device as an ACPI graphics device
72  * Be aware that the graphics device may not be physically present
73  * Use acpi_video_get_capabilities() to detect general ACPI video
74  * capabilities of present cards
75  */
76 long acpi_is_video_device(struct acpi_device *device)
77 {
78         acpi_handle h_dummy;
79         long video_caps = 0;
80
81         if (!device)
82                 return 0;
83
84         /* Does this device able to support video switching ? */
85         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) &&
86             ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
87                 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
88
89         /* Does this device able to retrieve a video ROM ? */
90         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy)))
91                 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
92
93         /* Does this device able to configure which video head to be POSTed ? */
94         if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy)) &&
95             ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy)) &&
96             ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy)))
97                 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
98
99         /* Only check for backlight functionality if one of the above hit. */
100         if (video_caps)
101                 acpi_walk_namespace(ACPI_TYPE_DEVICE, device->handle,
102                                     ACPI_UINT32_MAX, acpi_backlight_cap_match,
103                                     &video_caps, NULL);
104
105         return video_caps;
106 }
107 EXPORT_SYMBOL(acpi_is_video_device);
108
109 static acpi_status
110 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
111 {
112         long *cap = context;
113         struct pci_dev *dev;
114         struct acpi_device *acpi_dev;
115
116         const struct acpi_device_id video_ids[] = {
117                 {ACPI_VIDEO_HID, 0},
118                 {"", 0},
119         };
120         if (acpi_bus_get_device(handle, &acpi_dev))
121                 return AE_OK;
122
123         if (!acpi_match_device_ids(acpi_dev, video_ids)) {
124                 dev = acpi_get_pci_dev(handle);
125                 if (!dev)
126                         return AE_OK;
127                 pci_dev_put(dev);
128                 *cap |= acpi_is_video_device(acpi_dev);
129         }
130         return AE_OK;
131 }
132
133 /*
134  * Returns the video capabilities of a specific ACPI graphics device
135  *
136  * if NULL is passed as argument all ACPI devices are enumerated and
137  * all graphics capabilities of physically present devices are
138  * summerized and returned. This is cached and done only once.
139  */
140 long acpi_video_get_capabilities(acpi_handle graphics_handle)
141 {
142         long caps = 0;
143         struct acpi_device *tmp_dev;
144         acpi_status status;
145
146         if (acpi_video_caps_checked && graphics_handle == NULL)
147                 return acpi_video_support;
148
149         if (!graphics_handle) {
150                 /* Only do the global walk through all graphics devices once */
151                 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
152                                     ACPI_UINT32_MAX, find_video,
153                                     &caps, NULL);
154                 /* There might be boot param flags set already... */
155                 acpi_video_support |= caps;
156                 acpi_video_caps_checked = 1;
157                 /* Add blacklists here. Be careful to use the right *DMI* bits
158                  * to still be able to override logic via boot params, e.g.:
159                  *
160                  *   if (dmi_name_in_vendors("XY")) {
161                  *      acpi_video_support |=
162                  *              ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VENDOR;
163                  *      acpi_video_support |=
164                  *              ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
165                  *}
166                  */
167         } else {
168                 status = acpi_bus_get_device(graphics_handle, &tmp_dev);
169                 if (ACPI_FAILURE(status)) {
170                         ACPI_EXCEPTION((AE_INFO, status, "Invalid device"));
171                         return 0;
172                 }
173                 acpi_walk_namespace(ACPI_TYPE_DEVICE, graphics_handle,
174                                     ACPI_UINT32_MAX, find_video,
175                                     &caps, NULL);
176         }
177         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "We have 0x%lX video support %s %s\n",
178                           graphics_handle ? caps : acpi_video_support,
179                           graphics_handle ? "on device " : "in general",
180                           graphics_handle ? acpi_device_bid(tmp_dev) : ""));
181         return caps;
182 }
183 EXPORT_SYMBOL(acpi_video_get_capabilities);
184
185 /* Returns true if video.ko can do backlight switching */
186 int acpi_video_backlight_support(void)
187 {
188         /*
189          * We must check whether the ACPI graphics device is physically plugged
190          * in. Therefore this must be called after binding PCI and ACPI devices
191          */
192         if (!acpi_video_caps_checked)
193                 acpi_video_get_capabilities(NULL);
194
195         /* First check for boot param -> highest prio */
196         if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR)
197                 return 0;
198         else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO)
199                 return 1;
200
201         /* Then check for DMI blacklist -> second highest prio */
202         if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VENDOR)
203                 return 0;
204         else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VIDEO)
205                 return 1;
206
207         /* Then go the default way */
208         return acpi_video_support & ACPI_VIDEO_BACKLIGHT;
209 }
210 EXPORT_SYMBOL(acpi_video_backlight_support);
211
212 /*
213  * Returns true if video.ko can do display output switching.
214  * This does not work well/at all with binary graphics drivers
215  * which disable system io ranges and do it on their own.
216  */
217 int acpi_video_display_switch_support(void)
218 {
219         if (!acpi_video_caps_checked)
220                 acpi_video_get_capabilities(NULL);
221
222         if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VENDOR)
223                 return 0;
224         else if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO)
225                 return 1;
226
227         if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VENDOR)
228                 return 0;
229         else if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VIDEO)
230                 return 1;
231
232         return acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING;
233 }
234 EXPORT_SYMBOL(acpi_video_display_switch_support);
235
236 /*
237  * Use acpi_display_output=vendor/video or acpi_backlight=vendor/video
238  * To force that backlight or display output switching is processed by vendor
239  * specific acpi drivers or video.ko driver.
240  */
241 static int __init acpi_backlight(char *str)
242 {
243         if (str == NULL || *str == '\0')
244                 return 1;
245         else {
246                 if (!strcmp("vendor", str))
247                         acpi_video_support |=
248                                 ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
249                 if (!strcmp("video", str))
250                         acpi_video_support |=
251                                 ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO;
252         }
253         return 1;
254 }
255 __setup("acpi_backlight=", acpi_backlight);
256
257 static int __init acpi_display_output(char *str)
258 {
259         if (str == NULL || *str == '\0')
260                 return 1;
261         else {
262                 if (!strcmp("vendor", str))
263                         acpi_video_support |=
264                                 ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VENDOR;
265                 if (!strcmp("video", str))
266                         acpi_video_support |=
267                                 ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO;
268         }
269         return 1;
270 }
271 __setup("acpi_display_output=", acpi_display_output);