]> Gentwo Git Trees - linux/.git/commit
HID: logitech-hidpp: Do not assume FAP in hidpp_send_message_sync()
authorMavroudis Chatzilazaridis <mavchatz@protonmail.com>
Thu, 2 Oct 2025 19:30:58 +0000 (19:30 +0000)
committerJiri Kosina <jkosina@suse.com>
Tue, 14 Oct 2025 09:55:15 +0000 (11:55 +0200)
commitaba7963544d47d82cdf36602a6678a093af0299d
treea8abf52ea399120c7f657858dc44526687f59c27
parent55cafcac080a882fbeea1a49a7338211ff2494db
HID: logitech-hidpp: Do not assume FAP in hidpp_send_message_sync()

Currently, hidpp_send_message_sync() retries sending the message when the
device returns a busy error code, specifically HIDPP20_ERROR_BUSY, which
has a different meaning under RAP. This ends up being a problem because
this function is used for both FAP and RAP messages.

This issue is not noticeable on older receivers with unreachable devices
since they return HIDPP_ERROR_RESOURCE_ERROR (0x09), which is not equal to
HIDPP20_ERROR_BUSY (0x08).

However, newer receivers return HIDPP_ERROR_UNKNOWN_DEVICE (0x08) which
happens to equal to HIDPP20_ERROR_BUSY, causing unnecessary retries when
the device is not actually busy.

This is resolved by checking if the error response is FAP or RAP and
picking the respective ERROR_BUSY code.

Fixes: 60165ab774cb ("HID: logitech-hidpp: rework one more time the retries attempts")
Signed-off-by: Mavroudis Chatzilazaridis <mavchatz@protonmail.com>
Tested-by: Stuart Hayhurst <stuart.a.hayhurst@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
drivers/hid/hid-logitech-hidpp.c