[PATCH 12/20] drm/sun4i: Add bridge support

Maxime Ripard
2016-05-16T12:47:12Z

Our RGB bus can be either connected to a bridge or a panel. While the panel
support was already there, the bridge was not.

Fix that.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
drivers/gpu/drm/sun4i/sun4i_drv.c | 4 +--
drivers/gpu/drm/sun4i/sun4i_rgb.c | 56 +++++++++++++++++++++++++++-----------
drivers/gpu/drm/sun4i/sun4i_tcon.c | 48 ++++++++++++++++++++++++++++----
drivers/gpu/drm/sun4i/sun4i_tcon.h | 1 +
4 files changed, 86 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
index 257d2b4f3645..1f9e00db747d 100644
--- a/drivers/gpu/drm/sun4i/sun4i_drv.c
+++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
@@ -268,8 +268,8 @@ static int sun4i_drv_add_endpoints(struct device *dev,
}

/*
- * If the node is our TCON, the first port is used for our
- * panel, and will not be part of the
+ * If the node is our TCON, the first port is used for
+ * panel or bridges, and will not be part of the
* component framework.
*/
if (sun4i_drv_node_is_tcon(node)) {
diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.c b/drivers/gpu/drm/sun4i/sun4i_rgb.c
index b46d2c15dc95..c3c611b08269 100644
--- a/drivers/gpu/drm/sun4i/sun4i_rgb.c
+++ b/drivers/gpu/drm/sun4i/sun4i_rgb.c
@@ -161,7 +161,12 @@ static void sun4i_rgb_encoder_enable(struct drm_encoder *encoder)

DRM_DEBUG_DRIVER("Enabling RGB output\n");

- drm_panel_enable(tcon->panel);
+ if (!IS_ERR(tcon->panel))
+ drm_panel_enable(tcon->panel);
+
+ if (!IS_ERR(tcon->bridge))
+ drm_bridge_enable(tcon->bridge);
+
sun4i_tcon_channel_enable(tcon, 0);
}

@@ -174,7 +179,12 @@ static void sun4i_rgb_encoder_disable(struct drm_encoder *encoder)
DRM_DEBUG_DRIVER("Disabling RGB output\n");

sun4i_tcon_channel_disable(tcon, 0);
- drm_panel_disable(tcon->panel);
+
+ if (!IS_ERR(tcon->bridge))
+ drm_bridge_disable(tcon->bridge);
+
+ if (!IS_ERR(tcon->panel))
+ drm_panel_disable(tcon->panel);
}

static void sun4i_rgb_encoder_mode_set(struct drm_encoder *encoder,
@@ -216,10 +226,6 @@ int sun4i_rgb_init(struct drm_device *drm)
struct sun4i_rgb *rgb;
int ret;

- /* If we don't have a panel, there's no point in going on */
- if (IS_ERR(tcon->panel))
- return -ENODEV;
-
rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL);
if (!rgb)
return -ENOMEM;
@@ -240,19 +246,37 @@ int sun4i_rgb_init(struct drm_device *drm)
/* The RGB encoder can only work with the TCON channel 0 */
rgb->encoder.possible_crtcs = BIT(0);

- drm_connector_helper_add(&rgb->connector,
- &sun4i_rgb_con_helper_funcs);
- ret = drm_connector_init(drm, &rgb->connector,
- &sun4i_rgb_con_funcs,
- DRM_MODE_CONNECTOR_Unknown);
- if (ret) {
- dev_err(drm->dev, "Couldn't initialise the rgb connector\n");
- goto err_cleanup_connector;
+ if (!IS_ERR(tcon->panel)) {
+ drm_connector_helper_add(&rgb->connector,
+ &sun4i_rgb_con_helper_funcs);
+ ret = drm_connector_init(drm, &rgb->connector,
+ &sun4i_rgb_con_funcs,
+ DRM_MODE_CONNECTOR_Unknown);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't initialise the rgb connector\n");
+ goto err_cleanup_connector;
+ }
+
+ drm_mode_connector_attach_encoder(&rgb->connector,
+ &rgb->encoder);
+
+ ret = drm_panel_attach(tcon->panel, &rgb->connector);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't attach our panel\n");
+ goto err_cleanup_connector;
+ }
}

- drm_mode_connector_attach_encoder(&rgb->connector, &rgb->encoder);
+ if (!IS_ERR(tcon->bridge)) {
+ rgb->encoder.bridge = tcon->bridge;
+ tcon->bridge->encoder = &rgb->encoder;

- drm_panel_attach(tcon->panel, &rgb->connector);
+ ret = drm_bridge_attach(drm, tcon->bridge);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't attach our bridge\n");
+ goto err_cleanup_connector;
+ }
+ }

return 0;

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index eed6a9e8d9a6..4618d98913b4 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -432,6 +432,40 @@ static struct drm_panel *sun4i_tcon_find_panel(struct device_node *node)
return of_drm_find_panel(remote) ?: ERR_PTR(-EPROBE_DEFER);
}

+static struct drm_bridge *sun4i_tcon_find_bridge(struct device_node *node)
+{
+ struct device_node *port, *remote, *child;
+ struct device_node *end_node = NULL;
+
+ /* Inputs are listed first, then outputs */
+ port = of_graph_get_port_by_id(node, 1);
+
+ /*
+ * Our first output is the RGB interface where the panel will
+ * be connected.
+ */
+ for_each_child_of_node(port, child) {
+ u32 reg;
+
+ of_property_read_u32(child, "reg", &reg);
+ if (reg == 0)
+ end_node = child;
+ }
+
+ if (!end_node) {
+ DRM_DEBUG_DRIVER("Missing bridge endpoint\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ remote = of_graph_get_remote_port_parent(end_node);
+ if (!remote) {
+ DRM_DEBUG_DRIVER("Enable to parse remote node\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ return of_drm_find_bridge(remote) ?: ERR_PTR(-EPROBE_DEFER);
+}
+
static int sun4i_tcon_bind(struct device *dev, struct device *master,
void *data)
{
@@ -485,8 +519,9 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
}

tcon->panel = sun4i_tcon_find_panel(dev->of_node);
- if (IS_ERR(tcon->panel)) {
- dev_info(dev, "No panel found... RGB output disabled\n");
+ tcon->bridge = sun4i_tcon_find_bridge(dev->of_node);
+ if (IS_ERR(tcon->panel) && IS_ERR(tcon->bridge)) {
+ dev_info(dev, "No panel or bridge found... RGB output disabled\n");
return 0;
}

@@ -515,19 +550,22 @@ static struct component_ops sun4i_tcon_ops = {
static int sun4i_tcon_probe(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
+ struct drm_bridge *bridge;
struct drm_panel *panel;

/*
- * The panel is not ready.
+ * Neither the bridge or the panel is ready.
* Defer the probe.
*/
panel = sun4i_tcon_find_panel(node);
+ bridge = sun4i_tcon_find_bridge(node);

/*
* If we don't have a panel endpoint, just go on
*/
- if (PTR_ERR(panel) == -EPROBE_DEFER) {
- DRM_DEBUG_DRIVER("Still waiting for our panel. Deferring...\n");
+ if ((PTR_ERR(panel) == -EPROBE_DEFER) &&
+ (PTR_ERR(bridge) == -EPROBE_DEFER)) {
+ DRM_DEBUG_DRIVER("Still waiting for our panel/bridge. Deferring...\n");
return -EPROBE_DEFER;
}

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index 0e0b11db401b..31069027d7fb 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -162,6 +162,7 @@ struct sun4i_tcon {
/* Platform adjustments */
bool has_mux;

+ struct drm_bridge *bridge;
struct drm_panel *panel;
};

--
2.8.2