From: Srinivas Kandagatla srinivas.kandagatla@linaro.org
commit aa1262ca66957183ea1fb32a067e145b995f3744 upstream.
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@vger.kernel.org Fixes: a6e6581942ca ("soundwire: qcom: add auto enumeration support") Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Link: https://lore.kernel.org/r/20220706095644.5852-1-srinivas.kandagatla@linaro.o... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/soundwire/qcom.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -451,6 +451,10 @@ static int qcom_swrm_enumerate(struct sd 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);