kernel/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 <linux/workqueue.h>
  36 #include <acpi/video.h>
  37
  38 ACPI_MODULE_NAME("video");
  39 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  40
  41 void acpi_video_unregister_backlight(void);
  42
  43 static bool backlight_notifier_registered;
  44 static struct notifier_block backlight_nb;
  45 static struct work_struct backlight_notify_work;
  46
  47 static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
  48 static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
  49
  50 static void acpi_video_parse_cmdline(void)
  51 {
  52         if (!strcmp("vendor", acpi_video_backlight_string))
  53                 acpi_backlight_cmdline = acpi_backlight_vendor;
  54         if (!strcmp("video", acpi_video_backlight_string))
  55                 acpi_backlight_cmdline = acpi_backlight_video;
  56         if (!strcmp("native", acpi_video_backlight_string))
  57                 acpi_backlight_cmdline = acpi_backlight_native;
  58         if (!strcmp("none", acpi_video_backlight_string))
  59                 acpi_backlight_cmdline = acpi_backlight_none;
  60 }
  61
  62 static acpi_status
  63 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
  64 {
  65         long *cap = context;
  66         struct pci_dev *dev;
  67         struct acpi_device *acpi_dev;
  68
  69         static const struct acpi_device_id video_ids[] = {
  70                 {ACPI_VIDEO_HID, 0},
  71                 {"", 0},
  72         };
  73         if (acpi_bus_get_device(handle, &acpi_dev))
  74                 return AE_OK;
  75
  76         if (!acpi_match_device_ids(acpi_dev, video_ids)) {
  77                 dev = acpi_get_pci_dev(handle);
  78                 if (!dev)
  79                         return AE_OK;
  80                 pci_dev_put(dev);
  81                 *cap |= acpi_is_video_device(handle);
  82         }
  83         return AE_OK;
  84 }
  85
  86 /* Force to use vendor driver when the ACPI device is known to be
  87  * buggy */
  88 static int video_detect_force_vendor(const struct dmi_system_id *d)
  89 {
  90         acpi_backlight_dmi = acpi_backlight_vendor;
  91         return 0;
  92 }
  93
  94 static int video_detect_force_video(const struct dmi_system_id *d)
  95 {
  96         acpi_backlight_dmi = acpi_backlight_video;
  97         return 0;
  98 }
  99
 100 static int video_detect_force_native(const struct dmi_system_id *d)
 101 {
 102         acpi_backlight_dmi = acpi_backlight_native;
 103         return 0;
 104 }
 105
 106 static const struct dmi_system_id video_detect_dmi_table[] = {
 107         /* On Samsung X360, the BIOS will set a flag (VDRV) if generic
 108          * ACPI backlight device is used. This flag will definitively break
 109          * the backlight interface (even the vendor interface) untill next
 110          * reboot. It's why we should prevent video.ko from being used here
 111          * and we can't rely on a later call to acpi_video_unregister().
 112          */
 113         {
 114          .callback = video_detect_force_vendor,
 115          .ident = "X360",
 116          .matches = {
 117                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 118                 DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
 119                 DMI_MATCH(DMI_BOARD_NAME, "X360"),
 120                 },
 121         },
 122         {
 123         .callback = video_detect_force_vendor,
 124         .ident = "Asus UL30VT",
 125         .matches = {
 126                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 127                 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
 128                 },
 129         },
 130         {
 131         .callback = video_detect_force_vendor,
 132         .ident = "Asus UL30A",
 133         .matches = {
 134                 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 135                 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
 136                 },
 137         },
 138
 139         /*
 140          * These models have a working acpi_video backlight control, and using
 141          * native backlight causes a regression where backlight does not work
 142          * when userspace is not handling brightness key events. Disable
 143          * native_backlight on these to fix this:
 144          * https://bugzilla.kernel.org/show_bug.cgi?id=81691
 145          */
 146         {
 147          .callback = video_detect_force_video,
 148          .ident = "ThinkPad T420",
 149          .matches = {
 150                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 151                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
 152                 },
 153         },
 154         {
 155          .callback = video_detect_force_video,
 156          .ident = "ThinkPad T520",
 157          .matches = {
 158                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 159                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
 160                 },
 161         },
 162         {
 163          .callback = video_detect_force_video,
 164          .ident = "ThinkPad X201s",
 165          .matches = {
 166                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 167                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
 168                 },
 169         },
 170
 171         /* The native backlight controls do not work on some older machines */
 172         {
 173          /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
 174          .callback = video_detect_force_video,
 175          .ident = "HP ENVY 15 Notebook",
 176          .matches = {
 177                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 178                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
 179                 },
 180         },
 181         {
 182          .callback = video_detect_force_video,
 183          .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
 184          .matches = {
 185                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 186                 DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
 187                 },
 188         },
 189         {
 190          .callback = video_detect_force_video,
 191          .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
 192          .matches = {
 193                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 194                 DMI_MATCH(DMI_PRODUCT_NAME,
 195                           "370R4E/370R4V/370R5E/3570RE/370R5V"),
 196                 },
 197         },
 198         {
 199          /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
 200          .callback = video_detect_force_video,
 201          .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
 202          .matches = {
 203                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 204                 DMI_MATCH(DMI_PRODUCT_NAME,
 205                           "3570R/370R/470R/450R/510R/4450RV"),
 206                 },
 207         },
 208         {
 209          /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
 210          .callback = video_detect_force_video,
 211          .ident = "SAMSUNG 730U3E/740U3E",
 212          .matches = {
 213                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 214                 DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
 215                 },
 216         },
 217         {
 218          /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
 219          .callback = video_detect_force_video,
 220          .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
 221          .matches = {
 222                 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
 223                 DMI_MATCH(DMI_PRODUCT_NAME,
 224                           "900X3C/900X3D/900X3E/900X4C/900X4D"),
 225                 },
 226         },
 227         {
 228          /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
 229          .callback = video_detect_force_video,
 230          .ident = "Dell XPS14 L421X",
 231          .matches = {
 232                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 233                 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
 234                 },
 235         },
 236         {
 237          /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
 238          .callback = video_detect_force_video,
 239          .ident = "Dell XPS15 L521X",
 240          .matches = {
 241                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 242                 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
 243                 },
 244         },
 245
 246         /* Non win8 machines which need native backlight nevertheless */
 247         {
 248          /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
 249          .callback = video_detect_force_native,
 250          .ident = "Lenovo Ideapad S405",
 251          .matches = {
 252                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 253                 DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
 254                 },
 255         },
 256         {
 257          /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
 258          .callback = video_detect_force_native,
 259          .ident = "Lenovo Ideapad Z570",
 260          .matches = {
 261                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 262                 DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
 263                 },
 264         },
 265         {
 266          /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
 267          .callback = video_detect_force_native,
 268          .ident = "Apple MacBook Pro 12,1",
 269          .matches = {
 270                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 271                 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
 272                 },
 273         },
 274         { },
 275 };
 276
 277 /* This uses a workqueue to avoid various locking ordering issues */
 278 static void acpi_video_backlight_notify_work(struct work_struct *work)
 279 {
 280         if (acpi_video_get_backlight_type() != acpi_backlight_video)
 281                 acpi_video_unregister_backlight();
 282 }
 283
 284 static int acpi_video_backlight_notify(struct notifier_block *nb,
 285                                        unsigned long val, void *bd)
 286 {
 287         struct backlight_device *backlight = bd;
 288
 289         /* A raw bl registering may change video -> native */
 290         if (backlight->props.type == BACKLIGHT_RAW &&
 291             val == BACKLIGHT_REGISTERED)
 292                 schedule_work(&backlight_notify_work);
 293
 294         return NOTIFY_OK;
 295 }
 296
 297 /*
 298  * Determine which type of backlight interface to use on this system,
 299  * First check cmdline, then dmi quirks, then do autodetect.
 300  *
 301  * The autodetect order is:
 302  * 1) Is the acpi-video backlight interface supported ->
 303  *  no, use a vendor interface
 304  * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
 305  *  yes, use a native interface
 306  * 3) Else use the acpi-video interface
 307  *
 308  * Arguably the native on win8 check should be done first, but that would
 309  * be a behavior change, which may causes issues.
 310  */
 311 enum acpi_backlight_type acpi_video_get_backlight_type(void)
 312 {
 313         static DEFINE_MUTEX(init_mutex);
 314         static bool init_done;
 315         static long video_caps;
 316
 317         /* Parse cmdline, dmi and acpi only once */
 318         mutex_lock(&init_mutex);
 319         if (!init_done) {
 320                 acpi_video_parse_cmdline();
 321                 dmi_check_system(video_detect_dmi_table);
 322                 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
 323                                     ACPI_UINT32_MAX, find_video, NULL,
 324                                     &video_caps, NULL);
 325                 INIT_WORK(&backlight_notify_work,
 326                           acpi_video_backlight_notify_work);
 327                 backlight_nb.notifier_call = acpi_video_backlight_notify;
 328                 backlight_nb.priority = 0;
 329                 if (backlight_register_notifier(&backlight_nb) == 0)
 330                         backlight_notifier_registered = true;
 331                 init_done = true;
 332         }
 333         mutex_unlock(&init_mutex);
 334
 335         if (acpi_backlight_cmdline != acpi_backlight_undef)
 336                 return acpi_backlight_cmdline;
 337
 338         if (acpi_backlight_dmi != acpi_backlight_undef)
 339                 return acpi_backlight_dmi;
 340
 341         if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
 342                 return acpi_backlight_vendor;
 343
 344         if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW))
 345                 return acpi_backlight_native;
 346
 347         return acpi_backlight_video;
 348 }
 349 EXPORT_SYMBOL(acpi_video_get_backlight_type);
 350
 351 /*
 352  * Set the preferred backlight interface type based on DMI info.
 353  * This function allows DMI blacklists to be implemented by external
 354  * platform drivers instead of putting a big blacklist in video_detect.c
 355  */
 356 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
 357 {
 358         acpi_backlight_dmi = type;
 359         /* Remove acpi-video backlight interface if it is no longer desired */
 360         if (acpi_video_get_backlight_type() != acpi_backlight_video)
 361                 acpi_video_unregister_backlight();
 362 }
 363 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
 364
 365 void __exit acpi_video_detect_exit(void)
 366 {
 367         if (backlight_notifier_registered)
 368                 backlight_unregister_notifier(&backlight_nb);
 369 }