[PATCH v3 10/13] drm: bridge: samsung-dsim: Add atomic_get_input_bus_fmts

[Jagan Teki <jagan@amarulasolutions.com>]

Finding the right input bus format throughout the pipeline is hard
so add atomic_get_input_bus_fmts callback and initialize with the
default RGB888_1X24 bus format on DSI-end.

This format can be used in pipeline for negotiating bus format between
the DSI-end of this bridge and the other component closer to pipeline
components.

v3:
* include media-bus-format.h

v2:
* none

v1:
* new patch

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/bridge/samsung-dsim.c | 28 +++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 376e9682e130..2584343b767a 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -15,6 +15,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
+#include <linux/media-bus-format.h>
 #include <linux/of_device.h>
 #include <linux/phy/phy.h>
 
@@ -1339,6 +1340,32 @@ static void samsung_dsim_atomic_post_disable(struct drm_bridge *bridge,
 	pm_runtime_put_sync(dsi->dev);
 }
 
+#define MAX_INPUT_SEL_FORMATS	1
+
+static u32 *
+samsung_dsim_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
+				       struct drm_bridge_state *bridge_state,
+				       struct drm_crtc_state *crtc_state,
+				       struct drm_connector_state *conn_state,
+				       u32 output_fmt,
+				       unsigned int *num_input_fmts)
+{
+	u32 *input_fmts;
+
+	*num_input_fmts = 0;
+
+	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
+			     GFP_KERNEL);
+	if (!input_fmts)
+		return NULL;
+
+	/* This is the DSI-end bus format */
+	input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
+	*num_input_fmts = 1;
+
+	return input_fmts;
+}
+
 static int samsung_dsim_atomic_check(struct drm_bridge *bridge,
 				     struct drm_bridge_state *bridge_state,
 				     struct drm_crtc_state *crtc_state,
@@ -1378,6 +1405,7 @@ static const struct drm_bridge_funcs samsung_dsim_bridge_funcs = {
 	.atomic_duplicate_state		= drm_atomic_helper_bridge_duplicate_state,
 	.atomic_destroy_state		= drm_atomic_helper_bridge_destroy_state,
 	.atomic_reset			= drm_atomic_helper_bridge_reset,
+	.atomic_get_input_bus_fmts	= samsung_dsim_atomic_get_input_bus_fmts,
 	.atomic_check			= samsung_dsim_atomic_check,
 	.atomic_pre_enable		= samsung_dsim_atomic_pre_enable,
 	.atomic_enable			= samsung_dsim_atomic_enable,
-- 
2.25.1