[RFC PATCH 11/17] drm: bridge: samsung-dsim: Find the possible DSI devices

[Jagan Teki <jagan@amarulasolutions.com>]

Finding panel_or_bridge might vary based on associated
DSI device drivers like DSI panel, bridge, and I2C based
DSI bridge.

All of these DSI drivers will invoke the DSI host in order
to find the panel_or_bridge from probe to host attach and
bridge_attach to host bridge attach.

So, in order to handle all these cases of finding the
panel_or_bridge invoke the finding API in host attach and
bridge attach with the DSIM_STATE_DEVICE_FOUND flag.

This way we can handle all possible cases of finding the
DSI devices.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/bridge/samsung-dsim.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 2222c27feffd..9a2df1212d0f 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -248,6 +248,7 @@ struct samsung_dsim_transfer {
 #define DSIM_STATE_INITIALIZED		BIT(1)
 #define DSIM_STATE_CMD_LPM		BIT(2)
 #define DSIM_STATE_VIDOUT_AVAILABLE	BIT(3)
+#define DSIM_STATE_DEVICE_FOUND		BIT(4)
 
 struct samsung_dsim_driver_data {
 	const unsigned int *reg_ofs;
@@ -1475,6 +1476,15 @@ static int samsung_dsim_bridge_attach(struct drm_bridge *bridge,
 				      enum drm_bridge_attach_flags flags)
 {
 	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
+	int ret;
+
+	if (!(dsi->state & DSIM_STATE_DEVICE_FOUND)) {
+		ret = samsung_dsim_panel_or_bridge(dsi, dsi->dev->of_node);
+		if (ret)
+			return ret;
+
+		dsi->state |= DSIM_STATE_DEVICE_FOUND;
+	}
 
 	dsi->drm = bridge->dev;
 
@@ -1498,9 +1508,13 @@ static int samsung_dsim_host_attach(struct mipi_dsi_host *host,
 	struct drm_device *drm = dsi->drm;
 	int ret;
 
-	ret = samsung_dsim_panel_or_bridge(dsi, device->dev.of_node);
-	if (ret)
-		return ret;
+	if (!(dsi->state & DSIM_STATE_DEVICE_FOUND)) {
+		ret = samsung_dsim_panel_or_bridge(dsi, device->dev.of_node);
+		if (ret)
+			return ret;
+
+		dsi->state |= DSIM_STATE_DEVICE_FOUND;
+	}
 
 	/*
 	 * This is a temporary solution and should be made by more generic way.
-- 
2.25.1