drm/msm/mdp4: Initialize LCDC encoder even if panel driver isn't available
Currently, the driver defers if it doesn't find a drm_panel. This forces
us to have a drm_panel, if not, the driver isn't usable.
Make the lcdc encoder initialization independent of the availability of
the drm panel. We only check if there is a panel node specified in DT. If
it isn't, then we don't initialize the encoder at all. The panel node is
passed to the lcdc encoder and lvds connector drivers.
The connector driver takes the responsibility to retrieve the drm_panel
from the panel node, and update the status on whether the panel is
connected or not. This makes the panel usable even if the drm_panel
driver is inserted as a module later on.
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
index 379b435..6c9dd28 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
@@ -240,18 +240,18 @@
return 0;
}
-static struct drm_panel *detect_panel(struct drm_device *dev)
+static struct device_node *mdp4_detect_lcdc_panel(struct drm_device *dev)
{
struct device_node *endpoint, *panel_node;
struct device_node *np = dev->dev->of_node;
- struct drm_panel *panel = NULL;
endpoint = of_graph_get_next_endpoint(np, NULL);
if (!endpoint) {
- dev_err(dev->dev, "no valid endpoint\n");
- return ERR_PTR(-ENODEV);
+ DBG("no endpoint in MDP4 to fetch LVDS panel\n");
+ return NULL;
}
+ /* don't proceed if we have an endpoint but no panel_node tied to it */
panel_node = of_graph_get_remote_port_parent(endpoint);
if (!panel_node) {
dev_err(dev->dev, "no valid panel node\n");
@@ -261,13 +261,7 @@
of_node_put(endpoint);
- panel = of_drm_find_panel(panel_node);
- if (!panel) {
- of_node_put(panel_node);
- return ERR_PTR(-EPROBE_DEFER);
- }
-
- return panel;
+ return panel_node;
}
static int mdp4_modeset_init_intf(struct mdp4_kms *mdp4_kms,
@@ -277,18 +271,22 @@
struct msm_drm_private *priv = dev->dev_private;
struct drm_encoder *encoder;
struct drm_connector *connector;
- struct drm_panel *panel;
+ struct device_node *panel_node;
int ret;
switch (intf_type) {
case DRM_MODE_ENCODER_LVDS:
- panel = detect_panel(dev);
- if (IS_ERR(panel)) {
- dev_err(dev->dev, "failed to detect LVDS panel\n");
- return PTR_ERR(panel);
- }
+ /*
+ * bail out early if:
+ * - there is no panel node (no need to initialize lcdc
+ * encoder and lvds connector), or
+ * - panel node is a bad pointer
+ */
+ panel_node = mdp4_detect_lcdc_panel(dev);
+ if (IS_ERR_OR_NULL(panel_node))
+ return PTR_ERR(panel_node);
- encoder = mdp4_lcdc_encoder_init(dev, panel);
+ encoder = mdp4_lcdc_encoder_init(dev, panel_node);
if (IS_ERR(encoder)) {
dev_err(dev->dev, "failed to construct LCDC encoder\n");
return PTR_ERR(encoder);
@@ -297,7 +295,7 @@
/* LCDC can be hooked to DMA_P (TODO: Add DMA_S later?) */
encoder->possible_crtcs = 1 << DMA_P;
- connector = mdp4_lvds_connector_init(dev, panel, encoder);
+ connector = mdp4_lvds_connector_init(dev, panel_node, encoder);
if (IS_ERR(connector)) {
dev_err(dev->dev, "failed to initialize LVDS connector\n");
return PTR_ERR(connector);
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
index 8a7f6e1..7d03585 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
@@ -212,10 +212,10 @@
long mdp4_lcdc_round_pixclk(struct drm_encoder *encoder, unsigned long rate);
struct drm_encoder *mdp4_lcdc_encoder_init(struct drm_device *dev,
- struct drm_panel *panel);
+ struct device_node *panel_node);
struct drm_connector *mdp4_lvds_connector_init(struct drm_device *dev,
- struct drm_panel *panel, struct drm_encoder *encoder);
+ struct device_node *panel_node, struct drm_encoder *encoder);
#ifdef CONFIG_COMMON_CLK
struct clk *mpd4_lvds_pll_init(struct drm_device *dev);
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lcdc_encoder.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lcdc_encoder.c
index 4cd6e72..1bda2de 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lcdc_encoder.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lcdc_encoder.c
@@ -23,6 +23,7 @@
struct mdp4_lcdc_encoder {
struct drm_encoder base;
+ struct device_node *panel_node;
struct drm_panel *panel;
struct clk *lcdc_clk;
unsigned long int pixclock;
@@ -338,7 +339,7 @@
struct mdp4_lcdc_encoder *mdp4_lcdc_encoder =
to_mdp4_lcdc_encoder(encoder);
struct mdp4_kms *mdp4_kms = get_kms(encoder);
- struct drm_panel *panel = mdp4_lcdc_encoder->panel;
+ struct drm_panel *panel;
int i, ret;
if (WARN_ON(!mdp4_lcdc_encoder->enabled))
@@ -346,6 +347,7 @@
mdp4_write(mdp4_kms, REG_MDP4_LCDC_ENABLE, 0);
+ panel = of_drm_find_panel(mdp4_lcdc_encoder->panel_node);
if (panel) {
drm_panel_disable(panel);
drm_panel_unprepare(panel);
@@ -381,7 +383,7 @@
to_mdp4_lcdc_encoder(encoder);
unsigned long pc = mdp4_lcdc_encoder->pixclock;
struct mdp4_kms *mdp4_kms = get_kms(encoder);
- struct drm_panel *panel = mdp4_lcdc_encoder->panel;
+ struct drm_panel *panel;
int i, ret;
if (WARN_ON(mdp4_lcdc_encoder->enabled))
@@ -414,6 +416,7 @@
if (ret)
dev_err(dev->dev, "failed to enable lcdc_clk: %d\n", ret);
+ panel = of_drm_find_panel(mdp4_lcdc_encoder->panel_node);
if (panel) {
drm_panel_prepare(panel);
drm_panel_enable(panel);
@@ -442,7 +445,7 @@
/* initialize encoder */
struct drm_encoder *mdp4_lcdc_encoder_init(struct drm_device *dev,
- struct drm_panel *panel)
+ struct device_node *panel_node)
{
struct drm_encoder *encoder = NULL;
struct mdp4_lcdc_encoder *mdp4_lcdc_encoder;
@@ -455,7 +458,7 @@
goto fail;
}
- mdp4_lcdc_encoder->panel = panel;
+ mdp4_lcdc_encoder->panel_node = panel_node;
encoder = &mdp4_lcdc_encoder->base;
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lvds_connector.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lvds_connector.c
index 9211851..e73e174 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lvds_connector.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_lvds_connector.c
@@ -23,6 +23,7 @@
struct mdp4_lvds_connector {
struct drm_connector base;
struct drm_encoder *encoder;
+ struct device_node *panel_node;
struct drm_panel *panel;
};
#define to_mdp4_lvds_connector(x) container_of(x, struct mdp4_lvds_connector, base)
@@ -33,6 +34,10 @@
struct mdp4_lvds_connector *mdp4_lvds_connector =
to_mdp4_lvds_connector(connector);
+ if (!mdp4_lvds_connector->panel)
+ mdp4_lvds_connector->panel =
+ of_drm_find_panel(mdp4_lvds_connector->panel_node);
+
return mdp4_lvds_connector->panel ?
connector_status_connected :
connector_status_disconnected;
@@ -42,10 +47,6 @@
{
struct mdp4_lvds_connector *mdp4_lvds_connector =
to_mdp4_lvds_connector(connector);
- struct drm_panel *panel = mdp4_lvds_connector->panel;
-
- if (panel)
- drm_panel_detach(panel);
drm_connector_unregister(connector);
drm_connector_cleanup(connector);
@@ -60,9 +61,14 @@
struct drm_panel *panel = mdp4_lvds_connector->panel;
int ret = 0;
- if (panel)
+ if (panel) {
+ drm_panel_attach(panel, connector);
+
ret = panel->funcs->get_modes(panel);
+ drm_panel_detach(panel);
+ }
+
return ret;
}
@@ -111,7 +117,7 @@
/* initialize connector */
struct drm_connector *mdp4_lvds_connector_init(struct drm_device *dev,
- struct drm_panel *panel, struct drm_encoder *encoder)
+ struct device_node *panel_node, struct drm_encoder *encoder)
{
struct drm_connector *connector = NULL;
struct mdp4_lvds_connector *mdp4_lvds_connector;
@@ -124,7 +130,7 @@
}
mdp4_lvds_connector->encoder = encoder;
- mdp4_lvds_connector->panel = panel;
+ mdp4_lvds_connector->panel_node = panel_node;
connector = &mdp4_lvds_connector->base;
@@ -141,9 +147,6 @@
drm_mode_connector_attach_encoder(connector, encoder);
- if (panel)
- drm_panel_attach(panel, connector);
-
return connector;
fail: