[PATCH v4 02/13] soundwire: amd: return response on IMM status cleanup timeout

[Vijendar Mukunda]

amd_sdw_send_cmd_get_resp() reads the hardware response after
IMM_RES_VALID is set, then writes IMM_RES_VALID to acknowledge and
polls until the bit clears (status cleanup handshake).

When the cleanup poll timed out, the code returned the error without
writing *response, causing callers to report SDW_CMD_TIMEOUT and
discard a valid response - upper_resp and lower_resp had already been
read before the cleanup write.

The cleanup timeout indicates the hardware was slow to acknowledge
the clear of IMM_RES_VALID, not that the command exchange failed.
Log the anomaly, then write *response and return 0 so callers receive
the valid data. The stuck IMM_RES_VALID bit is cleared at the next
invocation by the existing bad-state guard.

Fixes: d8f48fbdfd9a ("soundwire: amd: Add support for AMD Manager driver")
Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@xxxxxxx>
---
 drivers/soundwire/amd_manager.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/soundwire/amd_manager.c b/drivers/soundwire/amd_manager.c
index 307cbfdb9442..0b83126b5ce6 100644
--- a/drivers/soundwire/amd_manager.c
+++ b/drivers/soundwire/amd_manager.c
@@ -285,11 +285,9 @@ static int amd_sdw_send_cmd_get_resp(struct amd_sdw_manager *amd_manager, u32 lo
 	writel(AMD_SDW_IMM_RES_VALID, amd_manager->mmio + ACP_SW_IMM_CMD_STS);
 	ret = readl_poll_timeout(amd_manager->mmio + ACP_SW_IMM_CMD_STS, sts,
 				 !(sts & AMD_SDW_IMM_RES_VALID), ACP_DELAY_US, AMD_SDW_TIMEOUT);
-	if (ret) {
+	if (ret)
 		dev_err(amd_manager->dev, "SDW%x cmd status retry failed\n",
 			amd_manager->instance);
-		return ret;
-	}
 	*response = ((u64)upper_resp << 32) | lower_resp;
 	return 0;
 }
-- 
2.53.0