linux-yocto/drivers/platform
Daniel Lee 26923ea48e platform/x86: lg-laptop: Fix WMAB call in fan_mode_store()
[ Upstream commit 3ed17349f18774c24505b0c21dfbd3cc4f126518 ]

When WMAB is called to set the fan mode, the new mode is read from either
bits 0-1 or bits 4-5 (depending on the value of some other EC register).
Thus when WMAB is called with bits 4-5 zeroed and called again with
bits 0-1 zeroed, the second call undoes the effect of the first call.
This causes writes to /sys/devices/platform/lg-laptop/fan_mode to have
no effect (and causes reads to always report a status of zero).

Fix this by calling WMAB once, with the mode set in bits 0,1 and 4,5.
When the fan mode is returned from WMAB it always has this form, so
there is no need to preserve the other bits.  As a bonus, the driver
now supports the "Performance" fan mode seen in the LG-provided Windows
control app, which provides less aggressive CPU throttling but louder
fan noise and shorter battery life.

Also, correct the documentation to reflect that 0 corresponds to the
default mode (what the Windows app calls "Optimal") and 1 corresponds
to the silent mode.

Fixes: dbf0c5a6b1 ("platform/x86: Add LG Gram laptop special features driver")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=204913#c4
Signed-off-by: Daniel Lee <dany97@live.ca>
Link: https://patch.msgid.link/MN2PR06MB55989CB10E91C8DA00EE868DDC1CA@MN2PR06MB5598.namprd06.prod.outlook.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-02 13:44:12 +02:00
..
arm64 move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
chrome platform/chrome: cros_ec: Unregister notifier in cros_ec_unregister() 2025-08-28 16:30:53 +02:00
cznic platform: cznic: CZNIC_PLATFORMS should depend on ARCH_MVEBU 2025-02-27 04:30:20 -08:00
goldfish platform/goldfish: goldfish_pipe: add missing MODULE_DESCRIPTION() macro 2024-07-03 16:40:46 +02:00
loongarch platform/loongarch: laptop: Add backlight power control support 2025-06-27 11:11:37 +01:00
mellanox platform/mellanox: mlxbf-pmc: Use kstrtobool() to check 0/1 input 2025-08-01 09:48:40 +01:00
mips platform: mips: cpu_hwmon: Disable driver on unsupported hardware 2024-06-21 10:22:10 +02:00
olpc platform-drivers-x86 for v6.12-1 2024-09-19 09:16:04 +02:00
surface move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
x86 platform/x86: lg-laptop: Fix WMAB call in fan_mode_store() 2025-10-02 13:44:12 +02:00
Kconfig platform: cznic: Add preliminary support for Turris Omnia MCU 2024-07-01 15:46:36 +02:00
Makefile platform-drivers-x86 for v6.11-1 2024-07-17 17:05:21 -07:00