[PATCH 2/9] drm/bridge: synopsys: dw-mipi-dsi: Add input bus format negotiation support

Liu Ying
2023-07-17T06:30:06Z

Introduce ->get_input_bus_fmts() callback to struct dw_mipi_dsi_plat_data
so that vendor drivers can implement specific methods to get input bus
formats for Synopsys DW MIPI DSI.

While at it, implement a generic callback for ->atomic_get_input_bus_fmts(),
where we try to get the input bus formats through pdata->get_input_bus_fmts()
first. If it's unavailable, fall back to the only format - MEDIA_BUS_FMT_FIXED,
which matches the default behavior if ->atomic_get_input_bus_fmts() is not
implemented as ->atomic_get_input_bus_fmts()'s kerneldoc indicates.

Signed-off-by: Liu Ying <victor.liu@nxp.com>
---
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 30 +++++++++++++++++++
include/drm/bridge/dw_mipi_dsi.h | 11 +++++++
2 files changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index 57eae0fdd970..8580b8a97fb1 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -12,6 +12,7 @@
#include <linux/component.h>
#include <linux/debugfs.h>
#include <linux/iopoll.h>
+#include <linux/media-bus-format.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pm_runtime.h>
@@ -536,6 +537,34 @@ static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
.transfer = dw_mipi_dsi_host_transfer,
};

+static u32 *
+dw_mipi_dsi_bridge_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)
+{
+ struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
+ const struct dw_mipi_dsi_plat_data *pdata = dsi->plat_data;
+ u32 *input_fmts;
+
+ if (pdata->get_input_bus_fmts)
+ return pdata->get_input_bus_fmts(pdata->priv_data,
+ bridge, bridge_state,
+ crtc_state, conn_state,
+ output_fmt, num_input_fmts);
+
+ /* Fall back to MEDIA_BUS_FMT_FIXED as the only input format. */
+ input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
+ if (!input_fmts)
+ return NULL;
+ input_fmts[0] = MEDIA_BUS_FMT_FIXED;
+ *num_input_fmts = 1;
+
+ return input_fmts;
+}
+
static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
{
u32 val;
@@ -1003,6 +1032,7 @@ static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge,
static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = {
.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+ .atomic_get_input_bus_fmts = dw_mipi_dsi_bridge_atomic_get_input_bus_fmts,
.atomic_reset = drm_atomic_helper_bridge_reset,
.atomic_enable = dw_mipi_dsi_bridge_atomic_enable,
.atomic_post_disable = dw_mipi_dsi_bridge_post_atomic_disable,
diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
index f54621b17a69..246650f2814f 100644
--- a/include/drm/bridge/dw_mipi_dsi.h
+++ b/include/drm/bridge/dw_mipi_dsi.h
@@ -11,7 +11,10 @@

#include <linux/types.h>

+#include <drm/drm_atomic.h>
#include <drm/drm_bridge.h>
+#include <drm/drm_connector.h>
+#include <drm/drm_crtc.h>
#include <drm/drm_modes.h>

struct drm_display_mode;
@@ -56,6 +59,14 @@ struct dw_mipi_dsi_plat_data {
unsigned long mode_flags,
u32 lanes, u32 format);

+ u32 *(*get_input_bus_fmts)(void *priv_data,
+ 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);
+
const struct dw_mipi_dsi_phy_ops *phy_ops;
const struct dw_mipi_dsi_host_ops *host_ops;

--
2.37.1