drm/vc4: Switch DPI to using the panel-bridge helper.

Another 100 lines of boilerplate gone, while allowing for bridges to
be connected in the display chain.

Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170511183128.25085-3-eric@anholt.net

diff --git a/drivers/gpu/drm/vc4/vc4_dpi.c b/drivers/gpu/drm/vc4/vc4_dpi.c
index 39d6808..2e0fe46 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_dpi.c
+++ b/drivers/gpu/drm/vc4/vc4_dpi.c
@@ -23,8 +23,10 @@
  */
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_edid.h>
+#include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 #include <linux/clk.h>
 #include <linux/component.h>
@@ -95,7 +97,8 @@ struct vc4_dpi {
 
        struct drm_encoder *encoder;
        struct drm_connector *connector;
-       struct drm_panel *panel;
+       struct drm_bridge *bridge;
+       bool is_panel_bridge;
 
        void __iomem *regs;
 
@@ -118,24 +121,6 @@ to_vc4_dpi_encoder(struct drm_encoder *encoder)
        return container_of(encoder, struct vc4_dpi_encoder, base.base);
 }
 
-/* VC4 DPI connector KMS struct */
-struct vc4_dpi_connector {
-       struct drm_connector base;
-       struct vc4_dpi *dpi;
-
-       /* Since the connector is attached to just the one encoder,
-        * this is the reference to it so we can do the best_encoder()
-        * hook.
-        */
-       struct drm_encoder *encoder;
-};
-
-static inline struct vc4_dpi_connector *
-to_vc4_dpi_connector(struct drm_connector *connector)
-{
-       return container_of(connector, struct vc4_dpi_connector, base);
-}
-
 #define DPI_REG(reg) { reg, #reg }
 static const struct {
        u32 reg;
@@ -167,80 +152,6 @@ int vc4_dpi_debugfs_regs(struct seq_file *m, void *unused)
 }
 #endif
 
-static enum drm_connector_status
-vc4_dpi_connector_detect(struct drm_connector *connector, bool force)
-{
-       struct vc4_dpi_connector *vc4_connector =
-               to_vc4_dpi_connector(connector);
-       struct vc4_dpi *dpi = vc4_connector->dpi;
-
-       if (dpi->panel)
-               return connector_status_connected;
-       else
-               return connector_status_disconnected;
-}
-
-static void vc4_dpi_connector_destroy(struct drm_connector *connector)
-{
-       drm_connector_unregister(connector);
-       drm_connector_cleanup(connector);
-}
-
-static int vc4_dpi_connector_get_modes(struct drm_connector *connector)
-{
-       struct vc4_dpi_connector *vc4_connector =
-               to_vc4_dpi_connector(connector);
-       struct vc4_dpi *dpi = vc4_connector->dpi;
-
-       if (dpi->panel)
-               return drm_panel_get_modes(dpi->panel);
-
-       return 0;
-}
-
-static const struct drm_connector_funcs vc4_dpi_connector_funcs = {
-       .dpms = drm_atomic_helper_connector_dpms,
-       .detect = vc4_dpi_connector_detect,
-       .fill_modes = drm_helper_probe_single_connector_modes,
-       .destroy = vc4_dpi_connector_destroy,
-       .reset = drm_atomic_helper_connector_reset,
-       .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
-       .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
-};
-
-static const struct drm_connector_helper_funcs vc4_dpi_connector_helper_funcs = {
-       .get_modes = vc4_dpi_connector_get_modes,
-};
-
-static struct drm_connector *vc4_dpi_connector_init(struct drm_device *dev,
-                                                   struct vc4_dpi *dpi)
-{
-       struct drm_connector *connector = NULL;
-       struct vc4_dpi_connector *dpi_connector;
-
-       dpi_connector = devm_kzalloc(dev->dev, sizeof(*dpi_connector),
-                                    GFP_KERNEL);
-       if (!dpi_connector)
-               return ERR_PTR(-ENOMEM);
-
-       connector = &dpi_connector->base;
-
-       dpi_connector->encoder = dpi->encoder;
-       dpi_connector->dpi = dpi;
-
-       drm_connector_init(dev, connector, &vc4_dpi_connector_funcs,
-                          DRM_MODE_CONNECTOR_DPI);
-       drm_connector_helper_add(connector, &vc4_dpi_connector_helper_funcs);
-
-       connector->polled = 0;
-       connector->interlace_allowed = 0;
-       connector->doublescan_allowed = 0;
-
-       drm_mode_connector_attach_encoder(connector, dpi->encoder);
-
-       return connector;
-}
-
 static const struct drm_encoder_funcs vc4_dpi_encoder_funcs = {
        .destroy = drm_encoder_cleanup,
 };
@@ -250,11 +161,7 @@ static void vc4_dpi_encoder_disable(struct drm_encoder *encoder)
        struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder);
        struct vc4_dpi *dpi = vc4_encoder->dpi;
 
-       drm_panel_disable(dpi->panel);
-
        clk_disable_unprepare(dpi->pixel_clock);
-
-       drm_panel_unprepare(dpi->panel);
 }
 
 static void vc4_dpi_encoder_enable(struct drm_encoder *encoder)
@@ -265,12 +172,6 @@ static void vc4_dpi_encoder_enable(struct drm_encoder *encoder)
        u32 dpi_c = DPI_ENABLE | DPI_OUTPUT_ENABLE_MODE;
        int ret;
 
-       ret = drm_panel_prepare(dpi->panel);
-       if (ret) {
-               DRM_ERROR("Panel failed to prepare\n");
-               return;
-       }
-
        if (dpi->connector->display_info.num_bus_formats) {
                u32 bus_format = dpi->connector->display_info.bus_formats[0];
 
@@ -321,13 +222,6 @@ static void vc4_dpi_encoder_enable(struct drm_encoder *encoder)
        ret = clk_prepare_enable(dpi->pixel_clock);
        if (ret)
                DRM_ERROR("Failed to set clock rate: %d\n", ret);
-
-       ret = drm_panel_enable(dpi->panel);
-       if (ret) {
-               DRM_ERROR("Panel failed to enable\n");
-               drm_panel_unprepare(dpi->panel);
-               return;
-       }
 }
 
 static bool vc4_dpi_encoder_mode_fixup(struct drm_encoder *encoder,
@@ -351,24 +245,34 @@ static const struct of_device_id vc4_dpi_dt_match[] = {
        {}
 };
 
-/* Walks the OF graph to find the panel node and then asks DRM to look
- * up the panel.
+/* Sets up the next link in the display chain, whether it's a panel or
+ * a bridge.
  */
-static struct drm_panel *vc4_dpi_get_panel(struct device *dev)
+static int vc4_dpi_init_bridge(struct vc4_dpi *dpi)
 {
-       struct device_node *panel_node;
-       struct device_node *np = dev->of_node;
+       struct device *dev = &dpi->pdev->dev;
        struct drm_panel *panel;
+       int ret;
 
-       /* don't proceed if we have an endpoint but no panel_node tied to it */
-       panel_node = of_graph_get_remote_node(np, 0, 0);
-       if (!panel_node)
-               return NULL;
+       ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0,
+                                         &panel, &dpi->bridge);
+       if (ret) {
+               /* If nothing was connected in the DT, that's not an
+                * error.
+                */
+               if (ret == -ENODEV)
+                       return 0;
+               else
+                       return ret;
+       }
 
-       panel = of_drm_find_panel(panel_node);
-       of_node_put(panel_node);
+       if (panel) {
+               dpi->bridge = drm_panel_bridge_add(panel,
+                                                  DRM_MODE_CONNECTOR_DPI);
+               dpi->is_panel_bridge = true;
+       }
 
-       return panel;
+       return drm_bridge_attach(dpi->encoder, dpi->bridge, NULL);
 }
 
 static int vc4_dpi_bind(struct device *dev, struct device *master, void *data)
@@ -422,20 +326,13 @@ static int vc4_dpi_bind(struct device *dev, struct device *master, void *data)
        if (ret)
                DRM_ERROR("Failed to turn on core clock: %d\n", ret);
 
-       dpi->panel = vc4_dpi_get_panel(dev);
-
        drm_encoder_init(drm, dpi->encoder, &vc4_dpi_encoder_funcs,
                         DRM_MODE_ENCODER_DPI, NULL);
        drm_encoder_helper_add(dpi->encoder, &vc4_dpi_encoder_helper_funcs);
 
-       dpi->connector = vc4_dpi_connector_init(drm, dpi);
-       if (IS_ERR(dpi->connector)) {
-               ret = PTR_ERR(dpi->connector);
+       ret = vc4_dpi_init_bridge(dpi);
+       if (ret)
                goto err_destroy_encoder;
-       }
-
-       if (dpi->panel)
-               drm_panel_attach(dpi->panel, dpi->connector);
 
        dev_set_drvdata(dev, dpi);
 
@@ -456,10 +353,9 @@ static void vc4_dpi_unbind(struct device *dev, struct device *master,
        struct vc4_dev *vc4 = to_vc4_dev(drm);
        struct vc4_dpi *dpi = dev_get_drvdata(dev);
 
-       if (dpi->panel)
-               drm_panel_detach(dpi->panel);
+       if (dpi->is_panel_bridge)
+               drm_panel_bridge_remove(dpi->bridge);
 
-       vc4_dpi_connector_destroy(dpi->connector);
        drm_encoder_cleanup(dpi->encoder);
 
        clk_disable_unprepare(dpi->core_clock);