drm_plane_helper.c
/*
* Copyright (C) 2014 Intel Corporation
*
* DRM universal plane helper functions
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/list.h>
#include <drm/drmP.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_rect.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_uapi.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_encoder.h>
#include <drm/drm_atomic_helper.h>
#define SUBPIXEL_MASK 0xffff
/**
* DOC: overview
*
* This helper library has two parts. The first part has support to implement
* primary plane support on top of the normal CRTC configuration interface.
* Since the legacy &drm_mode_config_funcs.set_config interface ties the primary
* plane together with the CRTC state this does not allow userspace to disable
* the primary plane itself. The default primary plane only expose XRBG8888 and
* ARGB8888 as valid pixel formats for the attached framebuffer.
*
* Drivers are highly recommended to implement proper support for primary
* planes, and newly merged drivers must not rely upon these transitional
* helpers.
*
* The second part also implements transitional helpers which allow drivers to
* gradually switch to the atomic helper infrastructure for plane updates. Once
* that switch is complete drivers shouldn't use these any longer, instead using
* the proper legacy implementations for update and disable plane hooks provided
* by the atomic helpers.
*
* Again drivers are strongly urged to switch to the new interfaces.
*
* The plane helpers share the function table structures with other helpers,
* specifically also the atomic helpers. See &struct drm_plane_helper_funcs for
* the details.
*/
/*
* Returns the connectors currently associated with a CRTC. This function
* should be called twice: once with a NULL connector list to retrieve
* the list size, and once with the properly allocated list to be filled in.
*/
static int get_connectors_for_crtc(struct drm_crtc *crtc,
struct drm_connector **connector_list,
int num_connectors)
{
struct drm_device *dev = crtc->dev;
struct drm_connector *connector;
struct drm_connector_list_iter conn_iter;
int count = 0;
/*
* Note: Once we change the plane hooks to more fine-grained locking we
* need to grab the connection_mutex here to be able to make these
* checks.
*/
WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
drm_connector_list_iter_begin(dev, &conn_iter);
drm_for_each_connector_iter(connector, &conn_iter) {
if (connector->encoder && connector->encoder->crtc == crtc) {
if (connector_list != NULL && count < num_connectors)
*(connector_list++) = connector;
count++;
}
}
drm_connector_list_iter_end(&conn_iter);
return count;
}
static int drm_plane_helper_check_update(struct drm_plane *plane,
struct drm_crtc *crtc,
struct drm_framebuffer *fb,
struct drm_rect *src,
struct drm_rect *dst,
unsigned int rotation,
int min_scale,
int max_scale,
bool can_position,
bool can_update_disabled,
bool *visible)
{
struct drm_plane_state plane_state = {
.plane = plane,
.crtc = crtc,
.fb = fb,
.src_x = src->x1,
.src_y = src->y1,
.src_w = drm_rect_width(src),
.src_h = drm_rect_height(src),
.crtc_x = dst->x1,
.crtc_y = dst->y1,
.crtc_w = drm_rect_width(dst),
.crtc_h = drm_rect_height(dst),
.rotation = rotation,
.visible = *visible,
};
struct drm_crtc_state crtc_state = {
.crtc = crtc,
.enable = crtc->enabled,
.mode = crtc->mode,
};
int ret;
ret = drm_atomic_helper_check_plane_state(&plane_state, &crtc_state,
min_scale, max_scale,
can_position,
can_update_disabled);
if (ret)
return ret;
*src = plane_state.src;
*dst = plane_state.dst;
*visible = plane_state.visible;
return 0;
}
static int drm_primary_helper_update(struct drm_plane *plane, struct drm_crtc *crtc,
struct drm_framebuffer *fb,
int crtc_x, int crtc_y,
unsigned int crtc_w, unsigned int crtc_h,
uint32_t src_x, uint32_t src_y,
uint32_t src_w, uint32_t src_h,
struct drm_modeset_acquire_ctx *ctx)
{
struct drm_mode_set set = {
.crtc = crtc,
.fb = fb,
.mode = &crtc->mode,
.x = src_x >> 16,
.y = src_y >> 16,
};
struct drm_rect src = {
.x1 = src_x,
.y1 = src_y,
.x2 = src_x + src_w,
.y2 = src_y + src_h,
};
struct drm_rect dest = {
.x1 = crtc_x,
.y1 = crtc_y,
.x2 = crtc_x + crtc_w,
.y2 = crtc_y + crtc_h,
};
struct drm_connector **connector_list;
int num_connectors, ret;
bool visible;
ret = drm_plane_helper_check_update(plane, crtc, fb,
&src, &dest,
DRM_MODE_ROTATE_0,
DRM_PLANE_HELPER_NO_SCALING,
DRM_PLANE_HELPER_NO_SCALING,
false, false, &visible);
if (ret)
return ret;
if (!visible)
/*
* Primary plane isn't visible. Note that unless a driver
* provides their own disable function, this will just
* wind up returning -EINVAL to userspace.
*/
return plane->funcs->disable_plane(plane, ctx);
/* Find current connectors for CRTC */
num_connectors = get_connectors_for_crtc(crtc, NULL, 0);
BUG_ON(num_connectors == 0);
connector_list = kcalloc(num_connectors, sizeof(*connector_list),
GFP_KERNEL);
if (!connector_list)
return -ENOMEM;
get_connectors_for_crtc(crtc, connector_list, num_connectors);
set.connectors = connector_list;
set.num_connectors = num_connectors;
/*
* We call set_config() directly here rather than using
* drm_mode_set_config_internal. We're reprogramming the same
* connectors that were already in use, so we shouldn't need the extra
* cross-CRTC fb refcounting to accomodate stealing connectors.
* drm_mode_setplane() already handles the basic refcounting for the
* framebuffers involved in this operation.
*/
ret = crtc->funcs->set_config(&set, ctx);
kfree(connector_list);
return ret;
}
static int drm_primary_helper_disable(struct drm_plane *plane,
struct drm_modeset_acquire_ctx *ctx)
{
return -EINVAL;
}
/**
* drm_primary_helper_destroy() - Helper for primary plane destruction
* @plane: plane to destroy
*
* Provides a default plane destroy handler for primary planes. This handler
* is called during CRTC destruction. We disable the primary plane, remove
* it from the DRM plane list, and deallocate the plane structure.
*/
void drm_primary_helper_destroy(struct drm_plane *plane)
{
drm_plane_cleanup(plane);
kfree(plane);
}
EXPORT_SYMBOL(drm_primary_helper_destroy);
const struct drm_plane_funcs drm_primary_helper_funcs = {
.update_plane = drm_primary_helper_update,
.disable_plane = drm_primary_helper_disable,
.destroy = drm_primary_helper_destroy,
};
EXPORT_SYMBOL(drm_primary_helper_funcs);