/**
* drm_plane_helper_check_update() - Check plane update for validity
* @plane: plane object to update
* @crtc: owning CRTC of owning plane
* @fb: framebuffer to flip onto plane
* @src: source coordinates in 16.16 fixed point
* @dest: integer destination coordinates
* @clip: integer clipping coordinates
* @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
* @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
* @can_position: is it legal to position the plane such that it
* doesn't cover the entire crtc? This will generally
* only be false for primary planes.
* @can_update_disabled: can the plane be updated while the crtc
* is disabled?
* @visible: output parameter indicating whether plane is still visible after
* clipping
*
* Checks that a desired plane update is valid. Drivers that provide
* their own plane handling rather than helper-provided implementations may
* still wish to call this function to avoid duplication of error checking
* code.
*
* RETURNS:
* Zero if update appears valid, error code on failure
*/
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 *dest,
const struct drm_rect *clip,
int min_scale,
int max_scale,
bool can_position,
bool can_update_disabled,
bool *visible)
{
int hscale, vscale;
if (!fb) {
*visible = false;
return 0;
}
/* crtc should only be NULL when disabling (i.e., !fb) */
if (WARN_ON(!crtc)) {
*visible = false;
return 0;
}
if (!crtc->enabled && !can_update_disabled) {
DRM_DEBUG_KMS("Cannot update plane of a disabled CRTC.\n");
return -EINVAL;
}
/* Check scaling */
hscale = drm_rect_calc_hscale(src, dest, min_scale, max_scale);
vscale = drm_rect_calc_vscale(src, dest, min_scale, max_scale);
if (hscale < 0 || vscale < 0) {
DRM_DEBUG_KMS("Invalid scaling of plane\n");
drm_rect_debug_print("src: ", src, true);
drm_rect_debug_print("dst: ", dest, false);
return -ERANGE;
}
*visible = drm_rect_clip_scaled(src, dest, clip, hscale, vscale);
if (!*visible)
/*
* Plane isn't visible; some drivers can handle this
* so we just return success here. Drivers that can't
* (including those that use the primary plane helper's
* update function) will return an error from their
* update_plane handler.
*/
return 0;
if (!can_position && !drm_rect_equals(dest, clip)) {
DRM_DEBUG_KMS("Plane must cover entire CRTC\n");
drm_rect_debug_print("dst: ", dest, false);
drm_rect_debug_print("clip: ", clip, false);
return -EINVAL;
}
return 0;
}
/**
* drm_plane_helper_check_state() - Check plane state for validity
* @state: plane state to check
* @clip: integer clipping coordinates
* @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
* @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
* @can_position: is it legal to position the plane such that it
* doesn't cover the entire crtc? This will generally
* only be false for primary planes.
* @can_update_disabled: can the plane be updated while the crtc
* is disabled?
*
* Checks that a desired plane update is valid, and updates various
* bits of derived state (clipped coordinates etc.). Drivers that provide
* their own plane handling rather than helper-provided implementations may
* still wish to call this function to avoid duplication of error checking
* code.
*
* RETURNS:
* Zero if update appears valid, error code on failure
*/
int drm_plane_helper_check_state(struct drm_plane_state *state,
const struct drm_rect *clip,
int min_scale,
int max_scale,
bool can_position,
bool can_update_disabled)
{
struct drm_crtc *crtc = state->crtc;
struct drm_framebuffer *fb = state->fb;
struct drm_rect *src = &state->src;
struct drm_rect *dst = &state->dst;
unsigned int rotation = state->rotation;
int hscale, vscale;
*src = drm_plane_state_src(state);
*dst = drm_plane_state_dest(state);
if (!fb) {
state->visible = false;
return 0;
}
/* crtc should only be NULL when disabling (i.e., !fb) */
if (WARN_ON(!crtc)) {
state->visible = false;
return 0;
}
if (!crtc->enabled && !can_update_disabled) {
DRM_DEBUG_KMS("Cannot update plane of a disabled CRTC.\n");
return -EINVAL;
}
drm_rect_rotate(src, fb->width << 16, fb->height << 16, rotation);
/* Check scaling */
hscale = drm_rect_calc_hscale(src, dst, min_scale, max_scale);
vscale = drm_rect_calc_vscale(src, dst, min_scale, max_scale);
if (hscale < 0 || vscale < 0) {
DRM_DEBUG_KMS("Invalid scaling of plane\n");
drm_rect_debug_print("src: ", &state->src, true);
drm_rect_debug_print("dst: ", &state->dst, false);
return -ERANGE;
}
state->visible = drm_rect_clip_scaled(src, dst, clip, hscale, vscale);
drm_rect_rotate_inv(src, fb->width << 16, fb->height << 16, rotation);
if (!state->visible)
/*
* Plane isn't visible; some drivers can handle this
* so we just return success here. Drivers that can't
* (including those that use the primary plane helper's
* update function) will return an error from their
* update_plane handler.
*/
return 0;
if (!can_position && !drm_rect_equals(dst, clip)) {
DRM_DEBUG_KMS("Plane must cover entire CRTC\n");
drm_rect_debug_print("dst: ", dst, false);
drm_rect_debug_print("clip: ", clip, false);
return -EINVAL;
}
return 0;
}