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v3.1
  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_acpi,
 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/acpi.h>
 
 37#include <linux/dmi.h>
 
 38#include <linux/pci.h>
 
 
 
 39
 40#define PREFIX "ACPI: "
 41
 42ACPI_MODULE_NAME("video");
 43#define _COMPONENT		ACPI_VIDEO_COMPONENT
 
 44
 45static long acpi_video_support;
 46static bool acpi_video_caps_checked;
 47
 48static acpi_status
 49acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
 50			  void **retyurn_value)
 51{
 52	long *cap = context;
 53	acpi_handle h_dummy;
 54
 55	if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) &&
 56	    ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) {
 57		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
 58				  "support\n"));
 59		*cap |= ACPI_VIDEO_BACKLIGHT;
 60		if (ACPI_FAILURE(acpi_get_handle(handle, "_BQC", &h_dummy)))
 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 device is a video device which can be handled by
 70 * 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(struct acpi_device *device)
 78{
 79	acpi_handle h_dummy;
 80	long video_caps = 0;
 81
 82	if (!device)
 83		return 0;
 84
 85	/* Is this device able to support video switching ? */
 86	if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) ||
 87	    ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
 88		video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
 89
 90	/* Is this device able to retrieve a video ROM ? */
 91	if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy)))
 92		video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
 93
 94	/* Is this device able to configure which video head to be POSTed ? */
 95	if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy)) &&
 96	    ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy)) &&
 97	    ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy)))
 98		video_caps |= ACPI_VIDEO_DEVICE_POSTING;
 99
100	/* Only check for backlight functionality if one of the above hit. */
101	if (video_caps)
102		acpi_walk_namespace(ACPI_TYPE_DEVICE, device->handle,
103				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
104				    &video_caps, NULL);
105
106	return video_caps;
107}
108EXPORT_SYMBOL(acpi_is_video_device);
109
110static acpi_status
111find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
112{
113	long *cap = context;
114	struct pci_dev *dev;
115	struct acpi_device *acpi_dev;
116
117	const struct acpi_device_id video_ids[] = {
118		{ACPI_VIDEO_HID, 0},
119		{"", 0},
120	};
121	if (acpi_bus_get_device(handle, &acpi_dev))
122		return AE_OK;
123
124	if (!acpi_match_device_ids(acpi_dev, video_ids)) {
125		dev = acpi_get_pci_dev(handle);
126		if (!dev)
127			return AE_OK;
128		pci_dev_put(dev);
129		*cap |= acpi_is_video_device(acpi_dev);
130	}
131	return AE_OK;
132}
133
134/*
135 * Returns the video capabilities of a specific ACPI graphics device
136 *
137 * if NULL is passed as argument all ACPI devices are enumerated and
138 * all graphics capabilities of physically present devices are
139 * summarized and returned. This is cached and done only once.
140 */
141long acpi_video_get_capabilities(acpi_handle graphics_handle)
142{
143	long caps = 0;
144	struct acpi_device *tmp_dev;
145	acpi_status status;
146
147	if (acpi_video_caps_checked && graphics_handle == NULL)
148		return acpi_video_support;
 
 
 
149
150	if (!graphics_handle) {
151		/* Only do the global walk through all graphics devices once */
152		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
153				    ACPI_UINT32_MAX, find_video, NULL,
154				    &caps, NULL);
155		/* There might be boot param flags set already... */
156		acpi_video_support |= caps;
157		acpi_video_caps_checked = 1;
158		/* Add blacklists here. Be careful to use the right *DMI* bits
159		 * to still be able to override logic via boot params, e.g.:
160		 *
161		 *   if (dmi_name_in_vendors("XY")) {
162		 *	acpi_video_support |=
163		 *		ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
164		 *}
165		 */
166	} else {
167		status = acpi_bus_get_device(graphics_handle, &tmp_dev);
168		if (ACPI_FAILURE(status)) {
169			ACPI_EXCEPTION((AE_INFO, status, "Invalid device"));
170			return 0;
171		}
172		acpi_walk_namespace(ACPI_TYPE_DEVICE, graphics_handle,
173				    ACPI_UINT32_MAX, find_video, NULL,
174				    &caps, NULL);
175	}
176	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "We have 0x%lX video support %s %s\n",
177			  graphics_handle ? caps : acpi_video_support,
178			  graphics_handle ? "on device " : "in general",
179			  graphics_handle ? acpi_device_bid(tmp_dev) : ""));
180	return caps;
181}
182EXPORT_SYMBOL(acpi_video_get_capabilities);
183
184/* Returns true if video.ko can do backlight switching */
185int acpi_video_backlight_support(void)
186{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
187	/*
188	 * We must check whether the ACPI graphics device is physically plugged
189	 * in. Therefore this must be called after binding PCI and ACPI devices
190	 */
191	if (!acpi_video_caps_checked)
192		acpi_video_get_capabilities(NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
193
194	/* First check for boot param -> highest prio */
195	if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR)
196		return 0;
197	else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO)
198		return 1;
199
200	/* Then check for DMI blacklist -> second highest prio */
201	if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VENDOR)
202		return 0;
203	else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VIDEO)
204		return 1;
205
206	/* Then go the default way */
207	return acpi_video_support & ACPI_VIDEO_BACKLIGHT;
 
 
 
 
208}
209EXPORT_SYMBOL(acpi_video_backlight_support);
210
211/*
212 * Use acpi_backlight=vendor/video to force that backlight switching
213 * is processed by vendor specific acpi drivers or video.ko driver.
 
 
 
 
 
 
 
 
 
 
214 */
215static int __init acpi_backlight(char *str)
216{
217	if (str == NULL || *str == '\0')
218		return 1;
219	else {
220		if (!strcmp("vendor", str))
221			acpi_video_support |=
222				ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
223		if (!strcmp("video", str))
224			acpi_video_support |=
225				ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO;
 
 
 
 
 
 
 
 
 
 
226	}
227	return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
228}
229__setup("acpi_backlight=", acpi_backlight);
v5.14.15
  1/*
  2 *  Copyright (C) 2015       Red Hat Inc.
  3 *                           Hans de Goede <hdegoede@redhat.com>
  4 *  Copyright (C) 2008       SuSE Linux Products GmbH
  5 *                           Thomas Renninger <trenn@suse.de>
  6 *
  7 *  May be copied or modified under the terms of the GNU General Public License
  8 *
  9 * video_detect.c:
 
 
 
 
 10 * After PCI devices are glued with ACPI devices
 11 * acpi_get_pci_dev() can be called to identify ACPI graphics
 12 * devices for which a real graphics card is plugged in
 13 *
 
 
 
 
 
 
 
 14 * Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
 15 * are available, video.ko should be used to handle the device.
 16 *
 17 * Otherwise vendor specific drivers like thinkpad_acpi, asus-laptop,
 18 * sony_acpi,... can take care about backlight brightness.
 19 *
 20 * Backlight drivers can use acpi_video_get_backlight_type() to determine
 21 * which driver should handle the backlight.
 
 
 22 *
 23 * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
 24 * this file will not be compiled and acpi_video_get_backlight_type() will
 25 * always return acpi_backlight_vendor.
 26 */
 27
 28#include <linux/export.h>
 29#include <linux/acpi.h>
 30#include <linux/backlight.h>
 31#include <linux/dmi.h>
 32#include <linux/module.h>
 33#include <linux/pci.h>
 34#include <linux/types.h>
 35#include <linux/workqueue.h>
 36#include <acpi/video.h>
 37
 38void acpi_video_unregister_backlight(void);
 39
 40static bool backlight_notifier_registered;
 41static struct notifier_block backlight_nb;
 42static struct work_struct backlight_notify_work;
 43
 44static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
 45static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
 46
 47static void acpi_video_parse_cmdline(void)
 
 
 48{
 49	if (!strcmp("vendor", acpi_video_backlight_string))
 50		acpi_backlight_cmdline = acpi_backlight_vendor;
 51	if (!strcmp("video", acpi_video_backlight_string))
 52		acpi_backlight_cmdline = acpi_backlight_video;
 53	if (!strcmp("native", acpi_video_backlight_string))
 54		acpi_backlight_cmdline = acpi_backlight_native;
 55	if (!strcmp("none", acpi_video_backlight_string))
 56		acpi_backlight_cmdline = acpi_backlight_none;
 
 
 
 
 
 
 
 57}
 58
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 59static acpi_status
 60find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
 61{
 62	long *cap = context;
 63	struct pci_dev *dev;
 64	struct acpi_device *acpi_dev;
 65
 66	static const struct acpi_device_id video_ids[] = {
 67		{ACPI_VIDEO_HID, 0},
 68		{"", 0},
 69	};
 70	if (acpi_bus_get_device(handle, &acpi_dev))
 71		return AE_OK;
 72
 73	if (!acpi_match_device_ids(acpi_dev, video_ids)) {
 74		dev = acpi_get_pci_dev(handle);
 75		if (!dev)
 76			return AE_OK;
 77		pci_dev_put(dev);
 78		*cap |= acpi_is_video_device(handle);
 79	}
 80	return AE_OK;
 81}
 82
 83/* Force to use vendor driver when the ACPI device is known to be
 84 * buggy */
 85static int video_detect_force_vendor(const struct dmi_system_id *d)
 
 
 
 
 
 86{
 87	acpi_backlight_dmi = acpi_backlight_vendor;
 88	return 0;
 89}
 90
 91static int video_detect_force_video(const struct dmi_system_id *d)
 92{
 93	acpi_backlight_dmi = acpi_backlight_video;
 94	return 0;
 95}
 96
 97static int video_detect_force_native(const struct dmi_system_id *d)
 98{
 99	acpi_backlight_dmi = acpi_backlight_native;
100	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
101}
 
102
103static int video_detect_force_none(const struct dmi_system_id *d)
 
104{
105	acpi_backlight_dmi = acpi_backlight_none;
106	return 0;
107}
108
109static const struct dmi_system_id video_detect_dmi_table[] = {
110	/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
111	 * ACPI backlight device is used. This flag will definitively break
112	 * the backlight interface (even the vendor interface) until next
113	 * reboot. It's why we should prevent video.ko from being used here
114	 * and we can't rely on a later call to acpi_video_unregister().
115	 */
116	{
117	 .callback = video_detect_force_vendor,
118	 .ident = "X360",
119	 .matches = {
120		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
121		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
122		DMI_MATCH(DMI_BOARD_NAME, "X360"),
123		},
124	},
125	{
126	.callback = video_detect_force_vendor,
127	.ident = "Asus UL30VT",
128	.matches = {
129		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
130		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
131		},
132	},
133	{
134	.callback = video_detect_force_vendor,
135	.ident = "Asus UL30A",
136	.matches = {
137		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
138		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
139		},
140	},
141	{
142	.callback = video_detect_force_vendor,
143	.ident = "GIGABYTE GB-BXBT-2807",
144	.matches = {
145		DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
146		DMI_MATCH(DMI_PRODUCT_NAME, "GB-BXBT-2807"),
147		},
148	},
149	{
150	.callback = video_detect_force_vendor,
151	.ident = "Sony VPCEH3U1E",
152	.matches = {
153		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
154		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
155		},
156	},
157
158	/*
159	 * These models have a working acpi_video backlight control, and using
160	 * native backlight causes a regression where backlight does not work
161	 * when userspace is not handling brightness key events. Disable
162	 * native_backlight on these to fix this:
163	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
164	 */
165	{
166	 .callback = video_detect_force_video,
167	 .ident = "ThinkPad T420",
168	 .matches = {
169		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
170		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
171		},
172	},
173	{
174	 .callback = video_detect_force_video,
175	 .ident = "ThinkPad T520",
176	 .matches = {
177		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
178		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
179		},
180	},
181	{
182	 .callback = video_detect_force_video,
183	 .ident = "ThinkPad X201s",
184	 .matches = {
185		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
186		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
187		},
188	},
189	{
190	 .callback = video_detect_force_video,
191	 .ident = "ThinkPad X201T",
192	 .matches = {
193		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
194		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
195		},
196	},
197
198	/* The native backlight controls do not work on some older machines */
199	{
200	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
201	 .callback = video_detect_force_video,
202	 .ident = "HP ENVY 15 Notebook",
203	 .matches = {
204		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
205		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
206		},
207	},
208	{
209	 .callback = video_detect_force_video,
210	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
211	 .matches = {
212		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
213		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
214		},
215	},
216	{
217	 .callback = video_detect_force_video,
218	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
219	 .matches = {
220		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
221		DMI_MATCH(DMI_PRODUCT_NAME,
222			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
223		},
224	},
225	{
226	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
227	 .callback = video_detect_force_video,
228	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
229	 .matches = {
230		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
231		DMI_MATCH(DMI_PRODUCT_NAME,
232			  "3570R/370R/470R/450R/510R/4450RV"),
233		},
234	},
235	{
236	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
237	 .callback = video_detect_force_video,
238	 .ident = "SAMSUNG 670Z5E",
239	 .matches = {
240		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
241		DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
242		},
243	},
244	{
245	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
246	 .callback = video_detect_force_video,
247	 .ident = "SAMSUNG 730U3E/740U3E",
248	 .matches = {
249		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
250		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
251		},
252	},
253	{
254	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
255	 .callback = video_detect_force_video,
256	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
257	 .matches = {
258		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
259		DMI_MATCH(DMI_PRODUCT_NAME,
260			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
261		},
262	},
263	{
264	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
265	 .callback = video_detect_force_video,
266	 .ident = "Dell XPS14 L421X",
267	 .matches = {
268		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
269		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
270		},
271	},
272	{
273	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
274	 .callback = video_detect_force_video,
275	 .ident = "Dell XPS15 L521X",
276	 .matches = {
277		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
278		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
279		},
280	},
281	{
282	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
283	 .callback = video_detect_force_video,
284	 .ident = "SAMSUNG 530U4E/540U4E",
285	 .matches = {
286		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
287		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
288		},
289	},
290	/* https://bugs.launchpad.net/bugs/1894667 */
291	{
292	 .callback = video_detect_force_video,
293	 .ident = "HP 635 Notebook",
294	 .matches = {
295		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
296		DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
297		},
298	},
299
300	/* Non win8 machines which need native backlight nevertheless */
301	{
302	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
303	 .callback = video_detect_force_native,
304	 .ident = "Lenovo Ideapad S405",
305	 .matches = {
306		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
307		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
308		},
309	},
310	{
311	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
312	 .callback = video_detect_force_native,
313	 .ident = "Lenovo Ideapad Z570",
314	 .matches = {
315		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
316		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
317		},
318	},
319	{
320	 .callback = video_detect_force_native,
321	 .ident = "Lenovo E41-25",
322	 .matches = {
323		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
324		DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
325		},
326	},
327	{
328	 .callback = video_detect_force_native,
329	 .ident = "Lenovo E41-45",
330	 .matches = {
331		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
332		DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
333		},
334	},
335	{
336	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
337	 .callback = video_detect_force_native,
338	 .ident = "Apple MacBook Pro 12,1",
339	 .matches = {
340		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
341		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
342		},
343	},
344	{
345	 .callback = video_detect_force_native,
346	 .ident = "Dell Vostro V131",
347	 .matches = {
348		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
349		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
350		},
351	},
352	{
353	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
354	 .callback = video_detect_force_native,
355	 .ident = "Dell XPS 17 L702X",
356	 .matches = {
357		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
358		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
359		},
360	},
361	{
362	 .callback = video_detect_force_native,
363	 .ident = "Dell Precision 7510",
364	 .matches = {
365		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
366		DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
367		},
368	},
369	{
370	 .callback = video_detect_force_native,
371	 .ident = "Acer Aspire 5738z",
372	 .matches = {
373		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
374		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
375		DMI_MATCH(DMI_BOARD_NAME, "JV50"),
376		},
377	},
378	{
379	 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
380	 .callback = video_detect_force_native,
381	 .ident = "Acer TravelMate 5735Z",
382	 .matches = {
383		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
384		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
385		DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
386		},
387	},
388	{
389	.callback = video_detect_force_native,
390	.ident = "ASUSTeK COMPUTER INC. GA401",
391	.matches = {
392		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
393		DMI_MATCH(DMI_PRODUCT_NAME, "GA401"),
394		},
395	},
396	{
397	.callback = video_detect_force_native,
398	.ident = "ASUSTeK COMPUTER INC. GA502",
399	.matches = {
400		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
401		DMI_MATCH(DMI_PRODUCT_NAME, "GA502"),
402		},
403	},
404	{
405	.callback = video_detect_force_native,
406	.ident = "ASUSTeK COMPUTER INC. GA503",
407	.matches = {
408		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
409		DMI_MATCH(DMI_PRODUCT_NAME, "GA503"),
410		},
411	},
412
413	/*
414	 * Desktops which falsely report a backlight and which our heuristics
415	 * for this do not catch.
416	 */
417	{
418	 .callback = video_detect_force_none,
419	 .ident = "Dell OptiPlex 9020M",
420	 .matches = {
421		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
422		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
423		},
424	},
425	{
426	 .callback = video_detect_force_none,
427	 .ident = "MSI MS-7721",
428	 .matches = {
429		DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
430		DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"),
431		},
432	},
433	{ },
434};
435
436/* This uses a workqueue to avoid various locking ordering issues */
437static void acpi_video_backlight_notify_work(struct work_struct *work)
438{
439	if (acpi_video_get_backlight_type() != acpi_backlight_video)
440		acpi_video_unregister_backlight();
441}
442
443static int acpi_video_backlight_notify(struct notifier_block *nb,
444				       unsigned long val, void *bd)
445{
446	struct backlight_device *backlight = bd;
447
448	/* A raw bl registering may change video -> native */
449	if (backlight->props.type == BACKLIGHT_RAW &&
450	    val == BACKLIGHT_REGISTERED)
451		schedule_work(&backlight_notify_work);
452
453	return NOTIFY_OK;
454}
 
455
456/*
457 * Determine which type of backlight interface to use on this system,
458 * First check cmdline, then dmi quirks, then do autodetect.
459 *
460 * The autodetect order is:
461 * 1) Is the acpi-video backlight interface supported ->
462 *  no, use a vendor interface
463 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
464 *  yes, use a native interface
465 * 3) Else use the acpi-video interface
466 *
467 * Arguably the native on win8 check should be done first, but that would
468 * be a behavior change, which may causes issues.
469 */
470enum acpi_backlight_type acpi_video_get_backlight_type(void)
471{
472	static DEFINE_MUTEX(init_mutex);
473	static bool init_done;
474	static long video_caps;
475
476	/* Parse cmdline, dmi and acpi only once */
477	mutex_lock(&init_mutex);
478	if (!init_done) {
479		acpi_video_parse_cmdline();
480		dmi_check_system(video_detect_dmi_table);
481		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
482				    ACPI_UINT32_MAX, find_video, NULL,
483				    &video_caps, NULL);
484		INIT_WORK(&backlight_notify_work,
485			  acpi_video_backlight_notify_work);
486		backlight_nb.notifier_call = acpi_video_backlight_notify;
487		backlight_nb.priority = 0;
488		if (backlight_register_notifier(&backlight_nb) == 0)
489			backlight_notifier_registered = true;
490		init_done = true;
491	}
492	mutex_unlock(&init_mutex);
493
494	if (acpi_backlight_cmdline != acpi_backlight_undef)
495		return acpi_backlight_cmdline;
496
497	if (acpi_backlight_dmi != acpi_backlight_undef)
498		return acpi_backlight_dmi;
499
500	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
501		return acpi_backlight_vendor;
502
503	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
504		return acpi_backlight_native;
505
506	return acpi_backlight_video;
507}
508EXPORT_SYMBOL(acpi_video_get_backlight_type);
509
510/*
511 * Set the preferred backlight interface type based on DMI info.
512 * This function allows DMI blacklists to be implemented by external
513 * platform drivers instead of putting a big blacklist in video_detect.c
514 */
515void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
516{
517	acpi_backlight_dmi = type;
518	/* Remove acpi-video backlight interface if it is no longer desired */
519	if (acpi_video_get_backlight_type() != acpi_backlight_video)
520		acpi_video_unregister_backlight();
521}
522EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
523
524void __exit acpi_video_detect_exit(void)
525{
526	if (backlight_notifier_registered)
527		backlight_unregister_notifier(&backlight_nb);
528}