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 } 350