drm/bridge: Refactor out the panel wrapper from the lvds-encoder bridge.
Many DRM drivers have common code to make a stub connector
implementation that wraps a drm_panel. By wrapping the panel in a DRM
bridge, all of the connector code (including calls during encoder
enable/disable) goes away.
v2: Fix build with CONFIG_DRM=m, drop "dev" argument that should just
be the panel's dev, move kerneldoc up a level and document
_remove().
v3: Fix another breakage with CONFIG_DRM=m, fix breakage with
CONFIG_OF=n, move protos under CONFIG_DRM_PANEL_BRIDGE, wrap a
line.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> (v2)
Acked-by: Archit Taneja <architt@codeaurora.org> (v2)
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170602202514.11900-1-eric@anholt.net
diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
new file mode 100644
index 0000000..99f9a4b
--- /dev/null
+++ b/drivers/gpu/drm/bridge/panel.c
@@ -0,0 +1,200 @@
+/*
+ * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ * Copyright (C) 2017 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_connector.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_encoder.h>
+#include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_panel.h>
+
+struct panel_bridge {
+ struct drm_bridge bridge;
+ struct drm_connector connector;
+ struct drm_panel *panel;
+ u32 connector_type;
+};
+
+static inline struct panel_bridge *
+drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
+{
+ return container_of(bridge, struct panel_bridge, bridge);
+}
+
+static inline struct panel_bridge *
+drm_connector_to_panel_bridge(struct drm_connector *connector)
+{
+ return container_of(connector, struct panel_bridge, connector);
+}
+
+static int panel_bridge_connector_get_modes(struct drm_connector *connector)
+{
+ struct panel_bridge *panel_bridge =
+ drm_connector_to_panel_bridge(connector);
+
+ return drm_panel_get_modes(panel_bridge->panel);
+}
+
+static const struct drm_connector_helper_funcs
+panel_bridge_connector_helper_funcs = {
+ .get_modes = panel_bridge_connector_get_modes,
+};
+
+static const struct drm_connector_funcs panel_bridge_connector_funcs = {
+ .dpms = drm_atomic_helper_connector_dpms,
+ .reset = drm_atomic_helper_connector_reset,
+ .fill_modes = drm_helper_probe_single_connector_modes,
+ .destroy = drm_connector_cleanup,
+ .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int panel_bridge_attach(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+ struct drm_connector *connector = &panel_bridge->connector;
+ int ret;
+
+ if (!bridge->encoder) {
+ DRM_ERROR("Missing encoder\n");
+ return -ENODEV;
+ }
+
+ drm_connector_helper_add(connector,
+ &panel_bridge_connector_helper_funcs);
+
+ ret = drm_connector_init(bridge->dev, connector,
+ &panel_bridge_connector_funcs,
+ panel_bridge->connector_type);
+ if (ret) {
+ DRM_ERROR("Failed to initialize connector\n");
+ return ret;
+ }
+
+ drm_mode_connector_attach_encoder(&panel_bridge->connector,
+ bridge->encoder);
+
+ ret = drm_panel_attach(panel_bridge->panel, &panel_bridge->connector);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static void panel_bridge_detach(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_panel_detach(panel_bridge->panel);
+}
+
+static void panel_bridge_pre_enable(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_panel_prepare(panel_bridge->panel);
+}
+
+static void panel_bridge_enable(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_panel_enable(panel_bridge->panel);
+}
+
+static void panel_bridge_disable(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_panel_disable(panel_bridge->panel);
+}
+
+static void panel_bridge_post_disable(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_panel_unprepare(panel_bridge->panel);
+}
+
+static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
+ .attach = panel_bridge_attach,
+ .detach = panel_bridge_detach,
+ .pre_enable = panel_bridge_pre_enable,
+ .enable = panel_bridge_enable,
+ .disable = panel_bridge_disable,
+ .post_disable = panel_bridge_post_disable,
+};
+
+/**
+ * drm_panel_bridge_add - Creates a drm_bridge and drm_connector that
+ * just calls the appropriate functions from drm_panel.
+ *
+ * @panel: The drm_panel being wrapped. Must be non-NULL.
+ * @connector_type: The DRM_MODE_CONNECTOR_* for the connector to be
+ * created.
+ *
+ * For drivers converting from directly using drm_panel: The expected
+ * usage pattern is that during either encoder module probe or DSI
+ * host attach, a drm_panel will be looked up through
+ * drm_of_find_panel_or_bridge(). drm_panel_bridge_add() is used to
+ * wrap that panel in the new bridge, and the result can then be
+ * passed to drm_bridge_attach(). The drm_panel_prepare() and related
+ * functions can be dropped from the encoder driver (they're now
+ * called by the KMS helpers before calling into the encoder), along
+ * with connector creation. When done with the bridge,
+ * drm_bridge_detach() should be called as normal, then
+ * drm_panel_bridge_remove() to free it.
+ */
+struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel,
+ u32 connector_type)
+{
+ struct panel_bridge *panel_bridge;
+ int ret;
+
+ if (!panel)
+ return ERR_PTR(EINVAL);
+
+ panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
+ GFP_KERNEL);
+ if (!panel_bridge)
+ return ERR_PTR(-ENOMEM);
+
+ panel_bridge->connector_type = connector_type;
+ panel_bridge->panel = panel;
+
+ panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
+#ifdef CONFIG_OF
+ panel_bridge->bridge.of_node = panel->dev->of_node;
+#endif
+
+ ret = drm_bridge_add(&panel_bridge->bridge);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return &panel_bridge->bridge;
+}
+EXPORT_SYMBOL(drm_panel_bridge_add);
+
+/**
+ * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
+ * created by drm_panel_bridge_add().
+ *
+ * @bridge: The drm_bridge being freed.
+ */
+void drm_panel_bridge_remove(struct drm_bridge *bridge)
+{
+ struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+ drm_bridge_remove(bridge);
+ devm_kfree(panel_bridge->panel->dev, bridge);
+}
+EXPORT_SYMBOL(drm_panel_bridge_remove);