drm/mxsfb: Update mxsfb to support a bridge

Currently, the MXSFB DRM driver only supports a panel. But, its output
display signal can also be redirected to another encoder, like a DSI
controller. In this case, that DSI controller may act like a drm_bridge.
In order support this use-case too, this patch adds support for drm_bridge
in mxsfb.

Signed-off-by: Robert Chiras <robert.chiras@nxp.com>
Tested-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1567078215-31601-2-git-send-email-robert.chiras@nxp.com

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
index 12421567af89938ee1c6a9187c87a1d53777e004..de09b93e60ea0abd3f76fd79294d2c7c54e5a67b 100644 (file)
--- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
@@ -95,8 +95,11 @@ static void mxsfb_set_bus_fmt(struct mxsfb_drm_private *mxsfb)
 
        reg = readl(mxsfb->base + LCDC_CTRL);
 
-       if (mxsfb->connector.display_info.num_bus_formats)
-               bus_format = mxsfb->connector.display_info.bus_formats[0];
+       if (mxsfb->connector->display_info.num_bus_formats)
+               bus_format = mxsfb->connector->display_info.bus_formats[0];
+
+       DRM_DEV_DEBUG_DRIVER(drm->dev, "Using bus_format: 0x%08X\n",
+                            bus_format);
 
        reg &= ~CTRL_BUS_WIDTH_MASK;
        switch (bus_format) {
@@ -204,8 +207,9 @@ static dma_addr_t mxsfb_get_fb_paddr(struct mxsfb_drm_private *mxsfb)
 
 static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 {
+       struct drm_device *drm = mxsfb->pipe.crtc.dev;
        struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode;
-       const u32 bus_flags = mxsfb->connector.display_info.bus_flags;
+       const u32 bus_flags = mxsfb->connector->display_info.bus_flags;
        u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
        int err;
 
@@ -229,6 +233,13 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 
        clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
 
+       DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
+                            m->crtc_clock,
+                            (int)(clk_get_rate(mxsfb->clk) / 1000));
+       DRM_DEV_DEBUG_DRIVER(drm->dev, "Connector bus_flags: 0x%08X\n",
+                            bus_flags);
+       DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
+
        writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
               TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
               mxsfb->base + mxsfb->devdata->transfer_count);

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
index e8506335cd1559c25fb04d0697a93833a2b3c52f..497cf443a9afa9f030bd8e659aff303a59528a9d 100644 (file)
--- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
@@ -101,9 +101,25 @@ static void mxsfb_pipe_enable(struct drm_simple_display_pipe *pipe,
                              struct drm_crtc_state *crtc_state,
                              struct drm_plane_state *plane_state)
 {
+       struct drm_connector *connector;
        struct mxsfb_drm_private *mxsfb = drm_pipe_to_mxsfb_drm_private(pipe);
        struct drm_device *drm = pipe->plane.dev;
 
+       if (!mxsfb->connector) {
+               list_for_each_entry(connector,
+                                   &drm->mode_config.connector_list,
+                                   head)
+                       if (connector->encoder == &mxsfb->pipe.encoder) {
+                               mxsfb->connector = connector;
+                               break;
+                       }
+       }
+
+       if (!mxsfb->connector) {
+               dev_warn(drm->dev, "No connector attached, using default\n");
+               mxsfb->connector = &mxsfb->panel_connector;
+       }
+
        pm_runtime_get_sync(drm->dev);
        drm_panel_prepare(mxsfb->panel);
        mxsfb_crtc_enable(mxsfb);
@@ -129,6 +145,9 @@ static void mxsfb_pipe_disable(struct drm_simple_display_pipe *pipe)
                drm_crtc_send_vblank_event(crtc, event);
        }
        spin_unlock_irq(&drm->event_lock);
+
+       if (mxsfb->connector != &mxsfb->panel_connector)
+               mxsfb->connector = NULL;
 }
 
 static void mxsfb_pipe_update(struct drm_simple_display_pipe *pipe,
@@ -226,16 +245,33 @@ static int mxsfb_load(struct drm_device *drm, unsigned long flags)
 
        ret = drm_simple_display_pipe_init(drm, &mxsfb->pipe, &mxsfb_funcs,
                        mxsfb_formats, ARRAY_SIZE(mxsfb_formats), NULL,
-                       &mxsfb->connector);
+                       mxsfb->connector);
        if (ret < 0) {
                dev_err(drm->dev, "Cannot setup simple display pipe\n");
                goto err_vblank;
        }
 
-       ret = drm_panel_attach(mxsfb->panel, &mxsfb->connector);
-       if (ret) {
-               dev_err(drm->dev, "Cannot connect panel\n");
-               goto err_vblank;
+       /*
+        * Attach panel only if there is one.
+        * If there is no panel attach, it must be a bridge. In this case, we
+        * need a reference to its connector for a proper initialization.
+        * We will do this check in pipe->enable(), since the connector won't
+        * be attached to an encoder until then.
+        */
+
+       if (mxsfb->panel) {
+               ret = drm_panel_attach(mxsfb->panel, mxsfb->connector);
+               if (ret) {
+                       dev_err(drm->dev, "Cannot connect panel: %d\n", ret);
+                       goto err_vblank;
+               }
+       } else if (mxsfb->bridge) {
+               ret = drm_simple_display_pipe_attach_bridge(&mxsfb->pipe,
+                                                           mxsfb->bridge);
+               if (ret) {
+                       dev_err(drm->dev, "Cannot connect bridge: %d\n", ret);
+                       goto err_vblank;
+               }
        }
 
        drm->mode_config.min_width      = MXSFB_MIN_XRES;

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.h b/drivers/gpu/drm/mxsfb/mxsfb_drv.h
index d975300dca05b1283e95aaea902bbc9e949a774b..0b65b5194a9cc501c5963a376c6468e6b4d3be95 100644 (file)
--- a/drivers/gpu/drm/mxsfb/mxsfb_drv.h
+++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.h
@@ -27,8 +27,10 @@ struct mxsfb_drm_private {
        struct clk                      *clk_disp_axi;
 
        struct drm_simple_display_pipe  pipe;
-       struct drm_connector            connector;
+       struct drm_connector            panel_connector;
+       struct drm_connector            *connector;
        struct drm_panel                *panel;
+       struct drm_bridge               *bridge;
 };
 
 int mxsfb_setup_crtc(struct drm_device *dev);

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_out.c b/drivers/gpu/drm/mxsfb/mxsfb_out.c
index be36f4d6cc964f2ed733e9670ea684e44ad17dfd..4eb94744c526322000098bcac69e01f28820e232 100644 (file)
--- a/drivers/gpu/drm/mxsfb/mxsfb_out.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_out.c
@@ -21,7 +21,8 @@
 static struct mxsfb_drm_private *
 drm_connector_to_mxsfb_drm_private(struct drm_connector *connector)
 {
-       return container_of(connector, struct mxsfb_drm_private, connector);
+       return container_of(connector, struct mxsfb_drm_private,
+                           panel_connector);
 }
 
 static int mxsfb_panel_get_modes(struct drm_connector *connector)
@@ -76,22 +77,23 @@ static const struct drm_connector_funcs mxsfb_panel_connector_funcs = {
 int mxsfb_create_output(struct drm_device *drm)
 {
        struct mxsfb_drm_private *mxsfb = drm->dev_private;
-       struct drm_panel *panel;
        int ret;
 
-       ret = drm_of_find_panel_or_bridge(drm->dev->of_node, 0, 0, &panel, NULL);
+       ret = drm_of_find_panel_or_bridge(drm->dev->of_node, 0, 0,
+                                         &mxsfb->panel, &mxsfb->bridge);
        if (ret)
                return ret;
 
-       mxsfb->connector.dpms = DRM_MODE_DPMS_OFF;
-       mxsfb->connector.polled = 0;
-       drm_connector_helper_add(&mxsfb->connector,
-                       &mxsfb_panel_connector_helper_funcs);
-       ret = drm_connector_init(drm, &mxsfb->connector,
-                                &mxsfb_panel_connector_funcs,
-                                DRM_MODE_CONNECTOR_Unknown);
-       if (!ret)
-               mxsfb->panel = panel;
+       if (mxsfb->panel) {
+               mxsfb->connector = &mxsfb->panel_connector;
+               mxsfb->connector->dpms = DRM_MODE_DPMS_OFF;
+               mxsfb->connector->polled = 0;
+               drm_connector_helper_add(mxsfb->connector,
+                                        &mxsfb_panel_connector_helper_funcs);
+               ret = drm_connector_init(drm, mxsfb->connector,
+                                        &mxsfb_panel_connector_funcs,
+                                        DRM_MODE_CONNECTOR_Unknown);
+       }
 
        return ret;
 }