[PATCH v1 2/2] drm/bridge/synopsys: dsi: Add a warning msg on dsi read operations

Philippe Cornu
2018-01-23T14:27:01Z

The DCS/GENERIC DSI read feature is not yet implemented so it
is important to warn the host_transfer() caller in case of
read operation requests.

Signed-off-by: Philippe Cornu <philippe.cornu@st.com>
---
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index 096cf5e5bb30..e46ddff8601c 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -417,7 +417,14 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
if (ret)
return ret;

- nb_bytes = packet.size;
+ if (msg->rx_buf && msg->rx_len > 0) {
+ /* TODO dw drv improvements: implement read feature */
+ dev_warn(dsi->dev, "read operations not yet implemented\n");
+ return -EPERM;
+
+ } else {
+ nb_bytes = packet.size;
+ }

return nb_bytes;
}
--
2.15.1