[PATCH 1/3] soundwire: cadence: Don't overflow the command FIFOs

Richard Fitzgerald
2022-12-01T13:49:05Z

The command FIFOs are 8 entries long, so change CDNS_MCP_CMD_LEN to 8.

CDNS_MCP_CMD_LEN was originally 32, which would lead to cdns_xfer_msg()
writing up to 32 commands into the FIFO, so any message longer than 8
commands would fail.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 2f52a5177caa ("soundwire: cdns: Add cadence library")
---
drivers/soundwire/cadence_master.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index a1de363eba3f..27699f341f2c 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -127,7 +127,8 @@ MODULE_PARM_DESC(cdns_mcp_int_mask, "Cadence MCP IntMask");

#define CDNS_MCP_CMD_BASE 0x80
#define CDNS_MCP_RESP_BASE 0x80
-#define CDNS_MCP_CMD_LEN 0x20
+/* FIFO can hold 8 commands */
+#define CDNS_MCP_CMD_LEN 8
#define CDNS_MCP_CMD_WORD_LEN 0x4

#define CDNS_MCP_CMD_SSP_TAG BIT(31)
--
2.30.2