Commit b3b3972a8bc806609579530d8291d5062c87b77b
Committed by
Greg Kroah-Hartman
Greg Kroah-Hartman
1 parent
37ae6d6884
samsung-laptop: Add use_native_backlight quirk, and enable it on some models
commit 4690555e13c48fef07f2762f6b0cd6b181e326d0 upstream. Since kernel 3.14 the backlight control has been broken on various Samsung Atom based netbooks. This has been bisected and this problem happens since commit b35684b8fa94 ("drm/i915: do full backlight setup at enable time") This has been reported and discussed in detail here: http://lists.freedesktop.org/archives/intel-gfx/2014-July/049395.html Unfortunately no-one has been able to fix this. This only affects Samsung Atom netbooks, and the Linux kernel and the BIOS of those laptops have never worked well together. All affected laptops already have a quirk to avoid using the standard acpi-video interface and instead use the samsung specific SABI interface which samsung-laptop uses. It seems that recent fixes to the i915 driver have also broken backlight control through the SABI interface. The intel_backlight driver OTOH works fine, and also allows for finer grained backlight control. So add a new use_native_backlight quirk, and replace the broken_acpi_video quirk with this quirk for affected models. This new quirk disables acpi-video as before and also stops samsung-laptop from registering the SABI based samsung_laptop backlight interface, leaving only the working intel_backlight interface. This commit enables this new quirk for 3 models which are known to be affected, chances are that it needs to be used on other models too. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1094948 # N145P BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1115713 # N250P Reported-by: Bertrik Sikken <bertrik@sikken.nl> # N150P Cc: stable@vger.kernel.org # 3.16 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Showing 1 changed file with 17 additions and 3 deletions Side-by-side Diff
drivers/platform/x86/samsung-laptop.c
| ... | ... | @@ -353,6 +353,7 @@ |
| 353 | 353 | bool broken_acpi_video; |
| 354 | 354 | bool four_kbd_backlight_levels; |
| 355 | 355 | bool enable_kbd_backlight; |
| 356 | + bool use_native_backlight; | |
| 356 | 357 | }; |
| 357 | 358 | |
| 358 | 359 | static struct samsung_quirks samsung_unknown = {}; |
| ... | ... | @@ -361,6 +362,10 @@ |
| 361 | 362 | .broken_acpi_video = true, |
| 362 | 363 | }; |
| 363 | 364 | |
| 365 | +static struct samsung_quirks samsung_use_native_backlight = { | |
| 366 | + .use_native_backlight = true, | |
| 367 | +}; | |
| 368 | + | |
| 364 | 369 | static struct samsung_quirks samsung_np740u3e = { |
| 365 | 370 | .four_kbd_backlight_levels = true, |
| 366 | 371 | .enable_kbd_backlight = true, |
| ... | ... | @@ -1507,7 +1512,7 @@ |
| 1507 | 1512 | DMI_MATCH(DMI_PRODUCT_NAME, "N150P"), |
| 1508 | 1513 | DMI_MATCH(DMI_BOARD_NAME, "N150P"), |
| 1509 | 1514 | }, |
| 1510 | - .driver_data = &samsung_broken_acpi_video, | |
| 1515 | + .driver_data = &samsung_use_native_backlight, | |
| 1511 | 1516 | }, |
| 1512 | 1517 | { |
| 1513 | 1518 | .callback = samsung_dmi_matched, |
| ... | ... | @@ -1517,7 +1522,7 @@ |
| 1517 | 1522 | DMI_MATCH(DMI_PRODUCT_NAME, "N145P/N250P/N260P"), |
| 1518 | 1523 | DMI_MATCH(DMI_BOARD_NAME, "N145P/N250P/N260P"), |
| 1519 | 1524 | }, |
| 1520 | - .driver_data = &samsung_broken_acpi_video, | |
| 1525 | + .driver_data = &samsung_use_native_backlight, | |
| 1521 | 1526 | }, |
| 1522 | 1527 | { |
| 1523 | 1528 | .callback = samsung_dmi_matched, |
| ... | ... | @@ -1557,7 +1562,7 @@ |
| 1557 | 1562 | DMI_MATCH(DMI_PRODUCT_NAME, "N250P"), |
| 1558 | 1563 | DMI_MATCH(DMI_BOARD_NAME, "N250P"), |
| 1559 | 1564 | }, |
| 1560 | - .driver_data = &samsung_broken_acpi_video, | |
| 1565 | + .driver_data = &samsung_use_native_backlight, | |
| 1561 | 1566 | }, |
| 1562 | 1567 | { |
| 1563 | 1568 | .callback = samsung_dmi_matched, |
| ... | ... | @@ -1615,6 +1620,15 @@ |
| 1615 | 1620 | } else if (samsung->quirks->broken_acpi_video) { |
| 1616 | 1621 | pr_info("Disabling ACPI video driver\n"); |
| 1617 | 1622 | acpi_video_unregister(); |
| 1623 | + } | |
| 1624 | + | |
| 1625 | + if (samsung->quirks->use_native_backlight) { | |
| 1626 | + pr_info("Using native backlight driver\n"); | |
| 1627 | + /* Tell acpi-video to not handle the backlight */ | |
| 1628 | + acpi_video_dmi_promote_vendor(); | |
| 1629 | + acpi_video_unregister(); | |
| 1630 | + /* And also do not handle it ourselves */ | |
| 1631 | + samsung->handle_backlight = false; | |
| 1618 | 1632 | } |
| 1619 | 1633 | #endif |
| 1620 | 1634 |