[PATCH 3/3] drm/msm/dsi: make sure we have panel or bridge earlier

Rob Clark
2019-06-30T13:16:09Z

From: Rob Clark <robdclark@chromium.org>

If we are going to -EPROBE_DEFER due to panel/bridge not probed yet, we
want to do it before we start touching hardware.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
drivers/gpu/drm/msm/dsi/dsi.h | 2 +-
drivers/gpu/drm/msm/dsi/dsi_host.c | 30 +++++++++++++--------------
drivers/gpu/drm/msm/dsi/dsi_manager.c | 9 +++-----
3 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
index 53bb124e8259..e15e7534ccd9 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.h
+++ b/drivers/gpu/drm/msm/dsi/dsi.h
@@ -171,7 +171,7 @@ int msm_dsi_host_set_display_mode(struct mipi_dsi_host *host,
struct drm_panel *msm_dsi_host_get_panel(struct mipi_dsi_host *host);
unsigned long msm_dsi_host_get_mode_flags(struct mipi_dsi_host *host);
struct drm_bridge *msm_dsi_host_get_bridge(struct mipi_dsi_host *host);
-int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer);
+int msm_dsi_host_register(struct mipi_dsi_host *host);
void msm_dsi_host_unregister(struct mipi_dsi_host *host);
int msm_dsi_host_set_src_pll(struct mipi_dsi_host *host,
struct msm_dsi_pll *src_pll);
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 1ae2f5522979..8e5b0ba9431e 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1824,6 +1824,20 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
goto fail;
}

+ /*
+ * Make sure we have panel or bridge early, before we start
+ * touching the hw. If bootloader enabled the display, we
+ * want to be sure to keep it running until the bridge/panel
+ * is probed and we are all ready to go. Otherwise we'll
+ * kill the display and then -EPROBE_DEFER
+ */
+ if (IS_ERR(of_drm_find_panel(msm_host->device_node)) &&
+ !of_drm_find_bridge(msm_host->device_node)) {
+ pr_err("%s: no panel or bridge yet\n", __func__);
+ return -EPROBE_DEFER;
+ }
+
+
msm_host->ctrl_base = msm_ioremap(pdev, "dsi_ctrl", "DSI CTRL");
if (IS_ERR(msm_host->ctrl_base)) {
pr_err("%s: unable to map Dsi ctrl base\n", __func__);
@@ -1941,7 +1955,7 @@ int msm_dsi_host_modeset_init(struct mipi_dsi_host *host,
return 0;
}

-int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
+int msm_dsi_host_register(struct mipi_dsi_host *host)
{
struct msm_dsi_host *msm_host = to_msm_dsi_host(host);
int ret;
@@ -1955,20 +1969,6 @@ int msm_dsi_host_register(struct mipi_dsi_host *host, bool check_defer)
return ret;

msm_host->registered = true;
-
- /* If the panel driver has not been probed after host register,
- * we should defer the host's probe.
- * It makes sure panel is connected when fbcon detects
- * connector status and gets the proper display mode to
- * create framebuffer.
- * Don't try to defer if there is nothing connected to the dsi
- * output
- */
- if (check_defer && msm_host->device_node) {
- if (IS_ERR(of_drm_find_panel(msm_host->device_node)))
- if (!of_drm_find_bridge(msm_host->device_node))
- return -EPROBE_DEFER;
- }
}

return 0;
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index ff39ce6150ad..cd3450dc3481 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -82,7 +82,7 @@ static int dsi_mgr_setup_components(int id)
int ret;

if (!IS_DUAL_DSI()) {
- ret = msm_dsi_host_register(msm_dsi->host, true);
+ ret = msm_dsi_host_register(msm_dsi->host);
if (ret)
return ret;

@@ -101,14 +101,11 @@ static int dsi_mgr_setup_components(int id)
/* Register slave host first, so that slave DSI device
* has a chance to probe, and do not block the master
* DSI device's probe.
- * Also, do not check defer for the slave host,
- * because only master DSI device adds the panel to global
- * panel list. The panel's device is the master DSI device.
*/
- ret = msm_dsi_host_register(slave_link_dsi->host, false);
+ ret = msm_dsi_host_register(slave_link_dsi->host);
if (ret)
return ret;
- ret = msm_dsi_host_register(master_link_dsi->host, true);
+ ret = msm_dsi_host_register(master_link_dsi->host);
if (ret)
return ret;

--
2.20.1