[PATCH] drm/bridge: sii902x: validate I2S data lane values

[Pengpeng Hou]

The sil,i2s-data-lanes property count is bounded, but each lane value
indexes a four-entry lane table.

Reject lane values outside the supported table before building the FIFO
sequence.

Signed-off-by: Pengpeng Hou <pengpeng@xxxxxxxxxxx>
---
 drivers/gpu/drm/bridge/sii902x.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index ea543be..d68f0a5 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -890,9 +890,16 @@ static int sii902x_audio_codec_init(struct sii902x *sii902x,
 	}
 	codec_data.max_i2s_channels = 2 * num_lanes;
 
-	for (i = 0; i < num_lanes; i++)
+	for (i = 0; i < num_lanes; i++) {
+		if (lanes[i] >= ARRAY_SIZE(i2s_lane_id)) {
+			dev_err(dev, "%s: invalid i2s data lane %u\n",
+				__func__, lanes[i]);
+			return -EINVAL;
+		}
+
 		sii902x->audio.i2s_fifo_sequence[i] |= audio_fifo_id[i] |
 			i2s_lane_id[lanes[i]] |	SII902X_TPI_I2S_FIFO_ENABLE;
+	}
 
 	sii902x->audio.mclk = devm_clk_get_optional(dev, "mclk");
 	if (IS_ERR(sii902x->audio.mclk)) {