Driver has to swap the endian before send brightness level value
to tcon.
v2: Use __be16 instead of u16 to fix sparse warning.
v3: Send one or two bytes brightness value depend on the precision.
v4: get data length of brightness value more easily.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Vandita Kulkarni <vandita.kulkarni@xxxxxxxxx>
Cc: Cooper Chiou <cooper.chiou@xxxxxxxxx>
Cc: William Tseng <william.tseng@xxxxxxxxx>
Signed-off-by: Lee Shawn C <shawn.c.lee@xxxxxxxxx>
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
.../i915/display/intel_dsi_dcs_backlight.c | 23 +++++++++++++------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
index 567c086602d5..f61ed82e8867 100644
--- a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
+++ b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
@@ -47,33 +47,42 @@ static u32 dcs_get_backlight(struct intel_connector *connector, enum pipe unused
{
struct intel_encoder *encoder = intel_attached_encoder(connector);
struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
+ struct intel_panel *panel = &connector->panel;
struct mipi_dsi_device *dsi_device;
- u8 data = 0;
+ u8 data[2] = {};
enum port port;
+ size_t len = panel->backlight.max > U8_MAX ? 2 : 1;
- /* FIXME: Need to take care of 16 bit brightness level */
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
- &data, sizeof(data));
+ &data, len);
break;
}
- return data;
+ return (data[1] << 8) | data[0];
}
static void dcs_set_backlight(const struct drm_connector_state *conn_state, u32 level)
{
struct intel_dsi *intel_dsi = enc_to_intel_dsi(to_intel_encoder(conn_state->best_encoder));
+ struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
struct mipi_dsi_device *dsi_device;
- u8 data = level;
+ u8 data[2] = {};
enum port port;
+ size_t len = panel->backlight.max > U8_MAX ? 2 : 1;
+
+ if (len == 1) {
+ data[0] = level;
+ } else {
+ data[0] = level >> 8;
+ data[1] = level;
+ }
- /* FIXME: Need to take care of 16 bit brightness level */
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
- &data, sizeof(data));
+ &data, len);
}
}
--
2.17.1
