This is a note to let you know that I've just added the patch titled
soundwire: qcom: Check device status before reading devid
to the 5.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
soundwire-qcom-check-device-status-before-reading-de.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 22279f33dd8646f63cc191b62fa6c863d0dd016b
Author: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Date: Wed Jul 6 10:56:44 2022 +0100
soundwire: qcom: Check device status before reading devid
[ Upstream commit aa1262ca66957183ea1fb32a067e145b995f3744 ]
As per hardware datasheet its recommended that we check the device
status before reading devid assigned by auto-enumeration.
Without this patch we see SoundWire devices with invalid enumeration
addresses on the bus.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: a6e6581942ca ("soundwire: qcom: add auto enumeration support")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220706095644.5852-1-srinivas.kandagatla@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index 22b706350ead..b5ec7726592c 100644
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -471,6 +471,10 @@ static int qcom_swrm_enumerate(struct sdw_bus *bus)
char *buf1 = (char *)&val1, *buf2 = (char *)&val2;
for (i = 1; i <= SDW_MAX_DEVICES; i++) {
+ /* do not continue if the status is Not Present */
+ if (!ctrl->status[i])
+ continue;
+
/*SCP_Devid5 - Devid 4*/
ctrl->reg_read(ctrl, SWRM_ENUMERATOR_SLAVE_DEV_ID_1(i), &val1);
