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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 * assigned
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 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-laptop,
27 * sony_acpi,... can take care about backlight brightness.
28 *
29 * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
30 * this file will not be compiled, acpi_video_get_capabilities() and
31 * acpi_video_backlight_support() will always return 0 and vendor specific
32 * drivers always can handle backlight.
33 *
34 */
35
36#include <linux/export.h>
37#include <linux/acpi.h>
38#include <linux/dmi.h>
39#include <linux/pci.h>
40
41#define PREFIX "ACPI: "
42
43ACPI_MODULE_NAME("video");
44#define _COMPONENT ACPI_VIDEO_COMPONENT
45
46static long acpi_video_support;
47static bool acpi_video_caps_checked;
48
49static acpi_status
50acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
51 void **retyurn_value)
52{
53 long *cap = context;
54 acpi_handle h_dummy;
55
56 if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) &&
57 ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) {
58 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
59 "support\n"));
60 *cap |= ACPI_VIDEO_BACKLIGHT;
61 if (ACPI_FAILURE(acpi_get_handle(handle, "_BQC", &h_dummy)))
62 printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
63 "cannot determine initial brightness\n");
64 /* We have backlight support, no need to scan further */
65 return AE_CTRL_TERMINATE;
66 }
67 return 0;
68}
69
70/* Returns true if the device is a video device which can be handled by
71 * video.ko.
72 * The device will get a Linux specific CID added in scan.c to
73 * identify the device as an ACPI graphics device
74 * Be aware that the graphics device may not be physically present
75 * Use acpi_video_get_capabilities() to detect general ACPI video
76 * capabilities of present cards
77 */
78long acpi_is_video_device(struct acpi_device *device)
79{
80 acpi_handle h_dummy;
81 long video_caps = 0;
82
83 if (!device)
84 return 0;
85
86 /* Is this device able to support video switching ? */
87 if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) ||
88 ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
89 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
90
91 /* Is this device able to retrieve a video ROM ? */
92 if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy)))
93 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
94
95 /* Is this device able to configure which video head to be POSTed ? */
96 if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy)) &&
97 ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy)) &&
98 ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy)))
99 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
100
101 /* Only check for backlight functionality if one of the above hit. */
102 if (video_caps)
103 acpi_walk_namespace(ACPI_TYPE_DEVICE, device->handle,
104 ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
105 &video_caps, NULL);
106
107 return video_caps;
108}
109EXPORT_SYMBOL(acpi_is_video_device);
110
111static acpi_status
112find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
113{
114 long *cap = context;
115 struct pci_dev *dev;
116 struct acpi_device *acpi_dev;
117
118 const struct acpi_device_id video_ids[] = {
119 {ACPI_VIDEO_HID, 0},
120 {"", 0},
121 };
122 if (acpi_bus_get_device(handle, &acpi_dev))
123 return AE_OK;
124
125 if (!acpi_match_device_ids(acpi_dev, video_ids)) {
126 dev = acpi_get_pci_dev(handle);
127 if (!dev)
128 return AE_OK;
129 pci_dev_put(dev);
130 *cap |= acpi_is_video_device(acpi_dev);
131 }
132 return AE_OK;
133}
134
135/*
136 * Returns the video capabilities of a specific ACPI graphics device
137 *
138 * if NULL is passed as argument all ACPI devices are enumerated and
139 * all graphics capabilities of physically present devices are
140 * summarized and returned. This is cached and done only once.
141 */
142long acpi_video_get_capabilities(acpi_handle graphics_handle)
143{
144 long caps = 0;
145 struct acpi_device *tmp_dev;
146 acpi_status status;
147
148 if (acpi_video_caps_checked && graphics_handle == NULL)
149 return acpi_video_support;
150
151 if (!graphics_handle) {
152 /* Only do the global walk through all graphics devices once */
153 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
154 ACPI_UINT32_MAX, find_video, NULL,
155 &caps, NULL);
156 /* There might be boot param flags set already... */
157 acpi_video_support |= caps;
158 acpi_video_caps_checked = 1;
159 /* Add blacklists here. Be careful to use the right *DMI* bits
160 * to still be able to override logic via boot params, e.g.:
161 *
162 * if (dmi_name_in_vendors("XY")) {
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, NULL,
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}
183EXPORT_SYMBOL(acpi_video_get_capabilities);
184
185/* Returns true if video.ko can do backlight switching */
186int 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}
210EXPORT_SYMBOL(acpi_video_backlight_support);
211
212/*
213 * Use acpi_backlight=vendor/video to force that backlight switching
214 * is processed by vendor specific acpi drivers or video.ko driver.
215 */
216static int __init acpi_backlight(char *str)
217{
218 if (str == NULL || *str == '\0')
219 return 1;
220 else {
221 if (!strcmp("vendor", str))
222 acpi_video_support |=
223 ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
224 if (!strcmp("video", str))
225 acpi_video_support |=
226 ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO;
227 }
228 return 1;
229}
230__setup("acpi_backlight=", acpi_backlight);
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 * assigned
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 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-laptop,
27 * sony_acpi,... can take care about backlight brightness.
28 *
29 * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
30 * this file will not be compiled, acpi_video_get_capabilities() and
31 * acpi_video_backlight_support() will always return 0 and vendor specific
32 * drivers always can handle backlight.
33 *
34 */
35
36#include <linux/export.h>
37#include <linux/acpi.h>
38#include <linux/dmi.h>
39#include <linux/pci.h>
40
41#include "internal.h"
42
43ACPI_MODULE_NAME("video");
44#define _COMPONENT ACPI_VIDEO_COMPONENT
45
46static long acpi_video_support;
47static bool acpi_video_caps_checked;
48
49static acpi_status
50acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
51 void **return_value)
52{
53 long *cap = context;
54
55 if (acpi_has_method(handle, "_BCM") &&
56 acpi_has_method(handle, "_BCL")) {
57 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
58 "support\n"));
59 *cap |= ACPI_VIDEO_BACKLIGHT;
60 if (!acpi_has_method(handle, "_BQC"))
61 printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, "
62 "cannot determine initial brightness\n");
63 /* We have backlight support, no need to scan further */
64 return AE_CTRL_TERMINATE;
65 }
66 return 0;
67}
68
69/* Returns true if the ACPI object is a video device which can be
70 * handled by video.ko.
71 * The device will get a Linux specific CID added in scan.c to
72 * identify the device as an ACPI graphics device
73 * Be aware that the graphics device may not be physically present
74 * Use acpi_video_get_capabilities() to detect general ACPI video
75 * capabilities of present cards
76 */
77long acpi_is_video_device(acpi_handle handle)
78{
79 long video_caps = 0;
80
81 /* Is this device able to support video switching ? */
82 if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
83 video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
84
85 /* Is this device able to retrieve a video ROM ? */
86 if (acpi_has_method(handle, "_ROM"))
87 video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
88
89 /* Is this device able to configure which video head to be POSTed ? */
90 if (acpi_has_method(handle, "_VPO") &&
91 acpi_has_method(handle, "_GPD") &&
92 acpi_has_method(handle, "_SPD"))
93 video_caps |= ACPI_VIDEO_DEVICE_POSTING;
94
95 /* Only check for backlight functionality if one of the above hit. */
96 if (video_caps)
97 acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
98 ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
99 &video_caps, NULL);
100
101 return video_caps;
102}
103EXPORT_SYMBOL(acpi_is_video_device);
104
105static acpi_status
106find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
107{
108 long *cap = context;
109 struct pci_dev *dev;
110 struct acpi_device *acpi_dev;
111
112 const struct acpi_device_id video_ids[] = {
113 {ACPI_VIDEO_HID, 0},
114 {"", 0},
115 };
116 if (acpi_bus_get_device(handle, &acpi_dev))
117 return AE_OK;
118
119 if (!acpi_match_device_ids(acpi_dev, video_ids)) {
120 dev = acpi_get_pci_dev(handle);
121 if (!dev)
122 return AE_OK;
123 pci_dev_put(dev);
124 *cap |= acpi_is_video_device(handle);
125 }
126 return AE_OK;
127}
128
129/* Force to use vendor driver when the ACPI device is known to be
130 * buggy */
131static int video_detect_force_vendor(const struct dmi_system_id *d)
132{
133 acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
134 return 0;
135}
136
137static struct dmi_system_id video_detect_dmi_table[] = {
138 /* On Samsung X360, the BIOS will set a flag (VDRV) if generic
139 * ACPI backlight device is used. This flag will definitively break
140 * the backlight interface (even the vendor interface) untill next
141 * reboot. It's why we should prevent video.ko from being used here
142 * and we can't rely on a later call to acpi_video_unregister().
143 */
144 {
145 .callback = video_detect_force_vendor,
146 .ident = "X360",
147 .matches = {
148 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
149 DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
150 DMI_MATCH(DMI_BOARD_NAME, "X360"),
151 },
152 },
153 {
154 .callback = video_detect_force_vendor,
155 .ident = "Asus UL30VT",
156 .matches = {
157 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
158 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
159 },
160 },
161 {
162 .callback = video_detect_force_vendor,
163 .ident = "Asus UL30A",
164 .matches = {
165 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
166 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
167 },
168 },
169 { },
170};
171
172/*
173 * Returns the video capabilities of a specific ACPI graphics device
174 *
175 * if NULL is passed as argument all ACPI devices are enumerated and
176 * all graphics capabilities of physically present devices are
177 * summarized and returned. This is cached and done only once.
178 */
179long acpi_video_get_capabilities(acpi_handle graphics_handle)
180{
181 long caps = 0;
182 struct acpi_device *tmp_dev;
183 acpi_status status;
184
185 if (acpi_video_caps_checked && graphics_handle == NULL)
186 return acpi_video_support;
187
188 if (!graphics_handle) {
189 /* Only do the global walk through all graphics devices once */
190 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
191 ACPI_UINT32_MAX, find_video, NULL,
192 &caps, NULL);
193 /* There might be boot param flags set already... */
194 acpi_video_support |= caps;
195 acpi_video_caps_checked = 1;
196 /* Add blacklists here. Be careful to use the right *DMI* bits
197 * to still be able to override logic via boot params, e.g.:
198 *
199 * if (dmi_name_in_vendors("XY")) {
200 * acpi_video_support |=
201 * ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
202 *}
203 */
204
205 dmi_check_system(video_detect_dmi_table);
206 } else {
207 status = acpi_bus_get_device(graphics_handle, &tmp_dev);
208 if (ACPI_FAILURE(status)) {
209 ACPI_EXCEPTION((AE_INFO, status, "Invalid device"));
210 return 0;
211 }
212 acpi_walk_namespace(ACPI_TYPE_DEVICE, graphics_handle,
213 ACPI_UINT32_MAX, find_video, NULL,
214 &caps, NULL);
215 }
216 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "We have 0x%lX video support %s %s\n",
217 graphics_handle ? caps : acpi_video_support,
218 graphics_handle ? "on device " : "in general",
219 graphics_handle ? acpi_device_bid(tmp_dev) : ""));
220 return caps;
221}
222EXPORT_SYMBOL(acpi_video_get_capabilities);
223
224static void acpi_video_caps_check(void)
225{
226 /*
227 * We must check whether the ACPI graphics device is physically plugged
228 * in. Therefore this must be called after binding PCI and ACPI devices
229 */
230 if (!acpi_video_caps_checked)
231 acpi_video_get_capabilities(NULL);
232}
233
234bool acpi_osi_is_win8(void)
235{
236 return acpi_gbl_osi_data >= ACPI_OSI_WIN_8;
237}
238EXPORT_SYMBOL(acpi_osi_is_win8);
239
240/* Promote the vendor interface instead of the generic video module.
241 * This function allow DMI blacklists to be implemented by externals
242 * platform drivers instead of putting a big blacklist in video_detect.c
243 * After calling this function you will probably want to call
244 * acpi_video_unregister() to make sure the video module is not loaded
245 */
246void acpi_video_dmi_promote_vendor(void)
247{
248 acpi_video_caps_check();
249 acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
250}
251EXPORT_SYMBOL(acpi_video_dmi_promote_vendor);
252
253/* To be called when a driver who previously promoted the vendor
254 * interface */
255void acpi_video_dmi_demote_vendor(void)
256{
257 acpi_video_caps_check();
258 acpi_video_support &= ~ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
259}
260EXPORT_SYMBOL(acpi_video_dmi_demote_vendor);
261
262/* Returns true if video.ko can do backlight switching */
263int acpi_video_backlight_support(void)
264{
265 acpi_video_caps_check();
266
267 /* First check for boot param -> highest prio */
268 if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR)
269 return 0;
270 else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO)
271 return 1;
272
273 /* Then check for DMI blacklist -> second highest prio */
274 if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VENDOR)
275 return 0;
276 else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VIDEO)
277 return 1;
278
279 /* Then go the default way */
280 return acpi_video_support & ACPI_VIDEO_BACKLIGHT;
281}
282EXPORT_SYMBOL(acpi_video_backlight_support);
283
284/*
285 * Use acpi_backlight=vendor/video to force that backlight switching
286 * is processed by vendor specific acpi drivers or video.ko driver.
287 */
288static int __init acpi_backlight(char *str)
289{
290 if (str == NULL || *str == '\0')
291 return 1;
292 else {
293 if (!strcmp("vendor", str))
294 acpi_video_support |=
295 ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
296 if (!strcmp("video", str))
297 acpi_video_support |=
298 ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO;
299 }
300 return 1;
301}
302__setup("acpi_backlight=", acpi_backlight);