drivers/acpi/video_detect.c

   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 <acpi/video.h>
  36
  37 ACPI_MODULE_NAME("video");
  38 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  39
  40 void acpi_video_unregister_backlight(void);
  41
  42 static bool backlight_notifier_registered;
  43 static struct notifier_block backlight_nb;
  44
  45 static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
  46 static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
  47
  48 static void acpi_video_parse_cmdline(void)
  49 {
  50         if (!strcmp("vendor", acpi_video_backlight_string))
  51                 acpi_backlight_cmdline = acpi_backlight_vendor;
  52         if (!strcmp("video", acpi_video_backlight_string))
  53                 acpi_backlight_cmdline = acpi_backlight_video;
  54         if (!strcmp("native", acpi_video_backlight_string))
  55                 acpi_backlight_cmdline = acpi_backlight_native;
  56         if (!strcmp("none", acpi_video_backlight_string))
  57                 acpi_backlight_cmdline = acpi_backlight_none;
  58 }
  59
  60 static acpi_status
  61 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
  62 {
  63         long *cap = context;
  64         struct pci_dev *dev;
  65         struct acpi_device *acpi_dev;
  66
  67         static const struct acpi_device_id video_ids[] = {
  68                 {ACPI_VIDEO_HID, 0},
  69                 {"", 0},
  70         };
  71         if (acpi_bus_get_device(handle, &acpi_dev))
  72                 return AE_OK;
  73
  74         if (!acpi_match_device_ids(acpi_dev, video_ids)) {
  75                 dev = acpi_get_pci_dev(handle);
  76                 if (!dev)
  77                         return AE_OK;
  78                 pci_dev_put(dev);
  79                 *cap |= acpi_is_video_device(handle);
  80         }
  81         return AE_OK;
  82 }
  83
  84 /* Force to use vendor driver when the ACPI device is known to be
  85  * buggy */
  86 static int video_detect_force_vendor(const struct dmi_system_id *d)
  87 {
  88         acpi_backlight_dmi = acpi_backlight_vendor;
  89         return 0;
  90 }
  91
  92 static int video_detect_force_video(const struct dmi_system_id *d)
  93 {
  94         acpi_backlight_dmi = acpi_backlight_video;
  95         return 0;
  96 }
  97
  98 static int video_detect_force_native(const struct dmi_system_id *d)
  99 {
 100         acpi_backlight_dmi = acpi_backlight_native;
 101         return 0;
 102 }
 103
 104 static const struct dmi_system_id video_detect_dmi_table[] = {
 105         /* On Samsung X360, the BIOS will set a flag (VDRV) if generic
 106          * ACPI backlight device is used. This flag will definitively break
 107          * the backlight interface (even the vendor interface) untill next
 108          * reboot. It's why we should prevent video.ko from being used here
 109          * and we can't rely on a later call to acpi_video_unregister().
 110          */
 111         {
 112          .callback = video_detect_force_vendor,
 113          .ident = "X360",
 114          .matches = {
 115                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 116                 DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
 117                 DMI_MATCH(DMI_BOARD_NAME, "X360"),
 118                 },
 119         },
 120         {
 121         .callback = video_detect_force_vendor,
 122         .ident = "Asus UL30VT",
 123         .matches = {
 124                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 125                 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
 126                 },
 127         },
 128         {
 129         .callback = video_detect_force_vendor,
 130         .ident = "Asus UL30A",
 131         .matches = {
 132                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 133                 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
 134                 },
 135         },
 136         {
 137         .callback = video_detect_force_vendor,
 138         .ident = "Dell Inspiron 5737",
 139         .matches = {
 140                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 141                 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5737"),
 142                 },
 143         },
 144
 145         /*
 146          * These models have a working acpi_video backlight control, and using
 147          * native backlight causes a regression where backlight does not work
 148          * when userspace is not handling brightness key events. Disable
 149          * native_backlight on these to fix this:
 150          * https://bugzilla.kernel.org/show_bug.cgi?id=81691
 151          */
 152         {
 153          .callback = video_detect_force_video,
 154          .ident = "ThinkPad T420",
 155          .matches = {
 156                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 157                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
 158                 },
 159         },
 160         {
 161          .callback = video_detect_force_video,
 162          .ident = "ThinkPad T520",
 163          .matches = {
 164                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 165                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
 166                 },
 167         },
 168         {
 169          .callback = video_detect_force_video,
 170          .ident = "ThinkPad X201s",
 171          .matches = {
 172                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 173                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
 174                 },
 175         },
 176
 177         /* The native backlight controls do not work on some older machines */
 178         {
 179          /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
 180          .callback = video_detect_force_video,
 181          .ident = "HP ENVY 15 Notebook",
 182          .matches = {
 183                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 184                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
 185                 },
 186         },
 187         {
 188          .callback = video_detect_force_video,
 189          .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
 190          .matches = {
 191                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 192                 DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
 193                 },
 194         },
 195         {
 196          .callback = video_detect_force_video,
 197          .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
 198          .matches = {
 199                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 200                 DMI_MATCH(DMI_PRODUCT_NAME,
 201                           "370R4E/370R4V/370R5E/3570RE/370R5V"),
 202                 },
 203         },
 204         {
 205          /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
 206          .callback = video_detect_force_video,
 207          .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
 208          .matches = {
 209                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 210                 DMI_MATCH(DMI_PRODUCT_NAME,
 211                           "3570R/370R/470R/450R/510R/4450RV"),
 212                 },
 213         },
 214         {
 215          /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
 216          .callback = video_detect_force_video,
 217          .ident = "SAMSUNG 730U3E/740U3E",
 218          .matches = {
 219                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 220                 DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
 221                 },
 222         },
 223         {
 224          /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
 225          .callback = video_detect_force_video,
 226          .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
 227          .matches = {
 228                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 229                 DMI_MATCH(DMI_PRODUCT_NAME,
 230                           "900X3C/900X3D/900X3E/900X4C/900X4D"),
 231                 },
 232         },
 233         {
 234          /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
 235          .callback = video_detect_force_video,
 236          .ident = "Dell XPS15 L521X",
 237          .matches = {
 238                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 239                 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
 240                 },
 241         },
 242
 243         /* Non win8 machines which need native backlight nevertheless */
 244         {
 245          /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
 246          .callback = video_detect_force_native,
 247          .ident = "Lenovo Ideapad Z570",
 248          .matches = {
 249                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 250                 DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
 251                 },
 252         },
 253         {
 254          /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
 255          .callback = video_detect_force_native,
 256          .ident = "Apple MacBook Pro 12,1",
 257          .matches = {
 258                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 259                 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
 260                 },
 261         },
 262         { },
 263 };
 264
 265 static int acpi_video_backlight_notify(struct notifier_block *nb,
 266                                        unsigned long val, void *bd)
 267 {
 268         struct backlight_device *backlight = bd;
 269
 270         /* A raw bl registering may change video -> native */
 271         if (backlight->props.type == BACKLIGHT_RAW &&
 272             val == BACKLIGHT_REGISTERED &&
 273             acpi_video_get_backlight_type() != acpi_backlight_video)
 274                 acpi_video_unregister_backlight();
 275
 276         return NOTIFY_OK;
 277 }
 278
 279 /*
 280  * Determine which type of backlight interface to use on this system,
 281  * First check cmdline, then dmi quirks, then do autodetect.
 282  *
 283  * The autodetect order is:
 284  * 1) Is the acpi-video backlight interface supported ->
 285  *  no, use a vendor interface
 286  * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
 287  *  yes, use a native interface
 288  * 3) Else use the acpi-video interface
 289  *
 290  * Arguably the native on win8 check should be done first, but that would
 291  * be a behavior change, which may causes issues.
 292  */
 293 enum acpi_backlight_type acpi_video_get_backlight_type(void)
 294 {
 295         static DEFINE_MUTEX(init_mutex);
 296         static bool init_done;
 297         static long video_caps;
 298
 299         /* Parse cmdline, dmi and acpi only once */
 300         mutex_lock(&init_mutex);
 301         if (!init_done) {
 302                 acpi_video_parse_cmdline();
 303                 dmi_check_system(video_detect_dmi_table);
 304                 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 305                                     ACPI_UINT32_MAX, find_video, NULL,
 306                                     &video_caps, NULL);
 307                 backlight_nb.notifier_call = acpi_video_backlight_notify;
 308                 backlight_nb.priority = 0;
 309                 if (backlight_register_notifier(&backlight_nb) == 0)
 310                         backlight_notifier_registered = true;
 311                 init_done = true;
 312         }
 313         mutex_unlock(&init_mutex);
 314
 315         if (acpi_backlight_cmdline != acpi_backlight_undef)
 316                 return acpi_backlight_cmdline;
 317
 318         if (acpi_backlight_dmi != acpi_backlight_undef)
 319                 return acpi_backlight_dmi;
 320
 321         if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
 322                 return acpi_backlight_vendor;
 323
 324         if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW))
 325                 return acpi_backlight_native;
 326
 327         return acpi_backlight_video;
 328 }
 329 EXPORT_SYMBOL(acpi_video_get_backlight_type);
 330
 331 /*
 332  * Set the preferred backlight interface type based on DMI info.
 333  * This function allows DMI blacklists to be implemented by external
 334  * platform drivers instead of putting a big blacklist in video_detect.c
 335  */
 336 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
 337 {
 338         acpi_backlight_dmi = type;
 339         /* Remove acpi-video backlight interface if it is no longer desired */
 340         if (acpi_video_get_backlight_type() != acpi_backlight_video)
 341                 acpi_video_unregister_backlight();
 342 }
 343 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
 344
 345 void __exit acpi_video_detect_exit(void)
 346 {
 347         if (backlight_notifier_registered)
 348                 backlight_unregister_notifier(&backlight_nb);
 349 }