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HID: logitech-hidpp: Do not assume FAP in hidpp_send_message_sync()

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[ Upstream commit aba7963544 ]

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: 60165ab774 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Mavroudis Chatzilazaridis
2025-10-02 19:30:58 +00:00
committed by Greg Kroah-Hartman
parent ac35eed934
commit 4e02cff54b
1 changed files with 7 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/hid/hid-logitech-hidpp.c
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@@ -352,10 +352,15 @@ static int hidpp_send_message_sync(struct hidpp_device *hidpp,
do {
ret = __do_hidpp_send_message_sync(hidpp, message, response);
if (ret != HIDPP20_ERROR_BUSY)
if (response->report_id == REPORT_ID_HIDPP_SHORT &&
ret != HIDPP_ERROR_BUSY)
break;
if ((response->report_id == REPORT_ID_HIDPP_LONG ||
response->report_id == REPORT_ID_HIDPP_VERY_LONG) &&
ret != HIDPP20_ERROR_BUSY)
break;
dbg_hid("%s:got busy hidpp 2.0 error %02X, retrying\n", __func__, ret);
dbg_hid("%s:got busy hidpp error %02X, retrying\n", __func__, ret);
} while (--max_retries);
mutex_unlock(&hidpp->send_mutex);