drm/msm/dsi: drop msm_dsi_device_connected() function

Since the commit 8f59ee9a ("drm/msm/dsi: Adjust probe order") the
DSI hosts are not bound through the component framework if the DSI
driver wasn't attached to the DSI device connected to this host.

Afterwards, if there is no bridge (including the panel bridge) created
for the DSI device then devm_drm_of_get_bridge() will return an error,
also making msm_dsi_manager_ext_bridge_init() and thus DSI modesetting
init fail.

This way there can be no 'unconnected' MSM DSI bridges. Remove the
msm_dsi_device_connected() function.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/561692/
Link: https://lore.kernel.org/r/20231009205727.2781802-3-dmitry.baryshkov@linaro.org

drivers/gpu/drm/msm/dsi/dsi.h

@@ -61,12 +61,6 @@ int msm_dsi_manager_register(struct msm_dsi *msm_dsi);
 void msm_dsi_manager_unregister(struct msm_dsi *msm_dsi);
 void msm_dsi_manager_tpg_enable(void);
 
-/* msm dsi */
-static inline bool msm_dsi_device_connected(struct msm_dsi *msm_dsi)
-{
-	return msm_dsi->external_bridge;
-}
-
 /* dsi host */
 struct msm_dsi_host;
 int msm_dsi_host_xfer_prepare(struct mipi_dsi_host *host,

drivers/gpu/drm/msm/dsi/dsi_manager.c

@@ -305,8 +305,6 @@ static void dsi_mgr_bridge_pre_enable(struct drm_bridge *bridge)
 	int ret;
 
 	DBG("id=%d", id);
-	if (!msm_dsi_device_connected(msm_dsi))
-		return;
 
 	/* Do nothing with the host if it is slave-DSI in case of bonded DSI */
 	if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id))
@@ -364,9 +362,6 @@ static void dsi_mgr_bridge_post_disable(struct drm_bridge *bridge)
 
 	DBG("id=%d", id);
 
-	if (!msm_dsi_device_connected(msm_dsi))
-		return;
-
 	/*
 	 * Do nothing with the host if it is slave-DSI in case of bonded DSI.
 	 * It is safe to call dsi_mgr_phy_disable() here because a single PHY