linux_dsm_epyc7002/drivers/gpu/drm/bridge/panel.c
Enric Balletbo i Serra 30be303108 drm/bridge: panel: Return always an error pointer in drm_panel_bridge_add()
Since commit 89958b7cd9 ("drm/bridge: panel: Infer connector type from
panel by default"), drm_panel_bridge_add() and their variants can return
NULL and an error pointer. This is fine but none of the actual users of
the API are checking for the NULL value. Instead of change all the
users, seems reasonable to return an error pointer instead. So change
the returned value for those functions when the connector type is unknown.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200416210654.2468805-1-enric.balletbo@collabora.com
2020-04-25 16:48:55 +02:00

330 lines
9.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
* Copyright (C) 2017 Broadcom
*/
#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_connector.h>
#include <drm/drm_encoder.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_panel.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.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, connector);
}
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 = {
.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,
enum drm_bridge_attach_flags flags)
{
struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
struct drm_connector *connector = &panel_bridge->connector;
int ret;
if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
return 0;
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_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 int panel_bridge_get_modes(struct drm_bridge *bridge,
struct drm_connector *connector)
{
struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
return drm_panel_get_modes(panel_bridge->panel, connector);
}
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,
.get_modes = panel_bridge_get_modes,
.atomic_reset = drm_atomic_helper_bridge_reset,
.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
};
/**
* 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.
*
* 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 (after
* drm_mode_config_cleanup() if the bridge has already been attached), then
* drm_panel_bridge_remove() to free it.
*
* The connector type is set to @panel->connector_type, which must be set to a
* known type. Calling this function with a panel whose connector type is
* DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
*
* See devm_drm_panel_bridge_add() for an automatically managed version of this
* function.
*/
struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
{
if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
return ERR_PTR(-EINVAL);
return drm_panel_bridge_add_typed(panel, panel->connector_type);
}
EXPORT_SYMBOL(drm_panel_bridge_add);
/**
* drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
* an explicit connector type.
* @panel: The drm_panel being wrapped. Must be non-NULL.
* @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
*
* This is just like drm_panel_bridge_add(), but forces the connector type to
* @connector_type instead of infering it from the panel.
*
* This function is deprecated and should not be used in new drivers. Use
* drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
* don't report a connector type.
*/
struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
u32 connector_type)
{
struct panel_bridge *panel_bridge;
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
panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
panel_bridge->bridge.type = connector_type;
drm_bridge_add(&panel_bridge->bridge);
return &panel_bridge->bridge;
}
EXPORT_SYMBOL(drm_panel_bridge_add_typed);
/**
* 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;
if (!bridge)
return;
if (bridge->funcs != &panel_bridge_bridge_funcs)
return;
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);
static void devm_drm_panel_bridge_release(struct device *dev, void *res)
{
struct drm_bridge **bridge = res;
drm_panel_bridge_remove(*bridge);
}
/**
* devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
* that just calls the appropriate functions from &drm_panel.
* @dev: device to tie the bridge lifetime to
* @panel: The drm_panel being wrapped. Must be non-NULL.
*
* This is the managed version of drm_panel_bridge_add() which automatically
* calls drm_panel_bridge_remove() when @dev is unbound.
*/
struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
struct drm_panel *panel)
{
if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
return ERR_PTR(-EINVAL);
return devm_drm_panel_bridge_add_typed(dev, panel,
panel->connector_type);
}
EXPORT_SYMBOL(devm_drm_panel_bridge_add);
/**
* devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
* &drm_connector with an explicit connector type.
* @dev: device to tie the bridge lifetime to
* @panel: The drm_panel being wrapped. Must be non-NULL.
* @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
*
* This is just like devm_drm_panel_bridge_add(), but forces the connector type
* to @connector_type instead of infering it from the panel.
*
* This function is deprecated and should not be used in new drivers. Use
* devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
* they don't report a connector type.
*/
struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
struct drm_panel *panel,
u32 connector_type)
{
struct drm_bridge **ptr, *bridge;
ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
bridge = drm_panel_bridge_add_typed(panel, connector_type);
if (!IS_ERR(bridge)) {
*ptr = bridge;
devres_add(dev, ptr);
} else {
devres_free(ptr);
}
return bridge;
}
EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
/**
* drm_panel_bridge_connector - return the connector for the panel bridge
* @bridge: The drm_bridge.
*
* drm_panel_bridge creates the connector.
* This function gives external access to the connector.
*
* Returns: Pointer to drm_connector
*/
struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
{
struct panel_bridge *panel_bridge;
panel_bridge = drm_bridge_to_panel_bridge(bridge);
return &panel_bridge->connector;
}
EXPORT_SYMBOL(drm_panel_bridge_connector);