linux-stable/drivers/platform
Damien Thébault 2502e5a025 platform/x86: dell-laptop: Fix backlight detection
Fix return code check for "max brightness" ACPI call.

The Dell laptop ACPI video brightness control is not present on dell
laptops anymore, but was present in older kernel versions.

The code that checks the return value is incorrect since the SMM
refactoring.

The old code was:
  if (buffer->output[0] == 0)

Which was changed to:
  ret = dell_send_request(...)
  if (ret)

However, dell_send_request() will return 0 if buffer->output[0] == 0,
so we must change the check to:
  if (ret == 0)

This issue was found on a Dell M4800 laptop, and the fix tested on it
as well.

Fixes: 549b4930f0 ("dell-smbios: Introduce dispatcher for SMM calls")
Signed-off-by: Damien Thébault <damien@dtbo.net>
Tested-by: Damien Thébault <damien@dtbo.net>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Reviewed-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2018-07-20 15:29:59 +03:00
..
chrome - New Device Support 2018-06-11 07:20:17 -07:00
goldfish vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
mellanox platform-drivers-x86 for v4.18-1 2018-06-14 16:30:30 +09:00
mips MIPS: Loongson-3: Support 4 packages in CPU Hwmon driver 2017-06-29 02:42:22 +02:00
olpc
x86 platform/x86: dell-laptop: Fix backlight detection 2018-07-20 15:29:59 +03:00
Kconfig platform/x86: Move Mellanox platform hotplug driver to platform/mellanox 2018-01-31 10:36:48 -08:00
Makefile platform/x86: Move Mellanox platform hotplug driver to platform/mellanox 2018-01-31 10:36:48 -08:00