From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
[ Upstream commit 49a467310dc4fae591a3547860ee04d8730780f4 ]
Reading will increase the fifo count, so check for outstanding cmd wrt.
write fifo depth to avoid overflow as read will also increase
write fifo cnt.
Fixes: a661308c34de ("soundwire: qcom: wait for fifo space to be available before read/write")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221026110210.6575-3-srinivas.kandagatla@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/soundwire/qcom.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index 87ccaebc8453..6e5990611d83 100644
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -380,6 +380,12 @@ static int qcom_swrm_cmd_fifo_rd_cmd(struct qcom_swrm_ctrl *swrm,
val = swrm_get_packed_reg_val(&swrm->rcmd_id, len, dev_addr, reg_addr);
+ /*
+ * Check for outstanding cmd wrt. write fifo depth to avoid
+ * overflow as read will also increase write fifo cnt.
+ */
+ swrm_wait_for_wr_fifo_avail(swrm);
+
/* wait for FIFO RD to complete to avoid overflow */
usleep_range(100, 105);
swrm->reg_write(swrm, SWRM_CMD_FIFO_RD_CMD, val);
--
2.35.1
