linux_kernel/drivers/gpu/drm/drm_atomic_state_helper.c
Daniel Vetter 51f644b40b drm/atomic-helper: reset vblank on crtc reset
Only when vblanks are supported ofc.

Some drivers do this already, but most unfortunately missed it. This
opens up bugs after driver load, before the crtc is enabled for the
first time. syzbot spotted this when loading vkms as a secondary
output. Given how many drivers are buggy it's best to solve this once
and for all in shared helper code.

Aside from moving the few existing calls to drm_crtc_vblank_reset into
helpers (i915 doesn't use helpers, so keeps its own) I think the
regression risk is minimal: atomic helpers already rely on drivers
calling drm_crtc_vblank_on/off correctly in their hooks when they
support vblanks. And driver that's failing to handle vblanks after
this is missing those calls already, and vblanks could only work by
accident when enabling a CRTC for the first time right after boot.

Big thanks to Tetsuo for helping track down what's going wrong here.

There's only a few drivers which already had the necessary call and
needed some updating:
- komeda, atmel and tidss also needed to be changed to call
  __drm_atomic_helper_crtc_reset() intead of open coding it
- tegra and msm even had it in the same place already, just code
  motion, and malidp already uses __drm_atomic_helper_crtc_reset().
- Laurent noticed that rcar-du and omap open-code their crtc reset and
  hence would actually be broken by this patch now. So fix them up by
  reusing the helpers, which brings the drm_crtc_vblank_reset() back.

Only call left is in i915, which doesn't use drm_mode_config_reset,
but has its own fastboot infrastructure. So that's the only case where
we actually want this in the driver still.

I've also reviewed all other drivers which set up vblank support with
drm_vblank_init. After the previous patch fixing mxsfb all atomic
drivers do call drm_crtc_vblank_on/off as they should, the remaining
drivers are either legacy kms or legacy dri1 drivers, so not affected
by this change to atomic helpers.

v2: Use the drm_dev_has_vblank() helper.

v3: Laurent pointed out that omap and rcar-du used drm_crtc_vblank_off
instead of drm_crtc_vblank_reset. Adjust them too.

v4: Laurent noticed that rcar-du and omap open-code their crtc reset
and hence would actually be broken by this patch now. So fix them up
by reusing the helpers, which brings the drm_crtc_vblank_reset() back.

v5: also mention rcar-du and ompadrm in the proper commit message
above (Laurent).

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://syzkaller.appspot.com/bug?id=0ba17d70d062b2595e1f061231474800f076c7cb
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot+0871b14ca2e2fb64f6e3@syzkaller.appspotmail.com
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: "James (Qian) Wang" <james.qian.wang@arm.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Mihail Atanassov <mihail.atanassov@arm.com>
Cc: Brian Starkey <brian.starkey@arm.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Brian Masney <masneyb@onstation.org>
Cc: Emil Velikov <emil.velikov@collabora.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-tegra@vger.kernel.org
Cc: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200612160056.2082681-1-daniel.vetter@ffwll.ch
2020-07-02 20:25:51 +02:00

660 lines
21 KiB
C

/*
* Copyright (C) 2018 Intel Corp.
*
* 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
*
* Authors:
* Rob Clark <robdclark@gmail.com>
* Daniel Vetter <daniel.vetter@ffwll.ch>
*/
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_connector.h>
#include <drm/drm_crtc.h>
#include <drm/drm_device.h>
#include <drm/drm_plane.h>
#include <drm/drm_print.h>
#include <drm/drm_vblank.h>
#include <drm/drm_writeback.h>
#include <linux/slab.h>
#include <linux/dma-fence.h>
/**
* DOC: atomic state reset and initialization
*
* Both the drm core and the atomic helpers assume that there is always the full
* and correct atomic software state for all connectors, CRTCs and planes
* available. Which is a bit a problem on driver load and also after system
* suspend. One way to solve this is to have a hardware state read-out
* infrastructure which reconstructs the full software state (e.g. the i915
* driver).
*
* The simpler solution is to just reset the software state to everything off,
* which is easiest to do by calling drm_mode_config_reset(). To facilitate this
* the atomic helpers provide default reset implementations for all hooks.
*
* On the upside the precise state tracking of atomic simplifies system suspend
* and resume a lot. For drivers using drm_mode_config_reset() a complete recipe
* is implemented in drm_atomic_helper_suspend() and drm_atomic_helper_resume().
* For other drivers the building blocks are split out, see the documentation
* for these functions.
*/
/**
* __drm_atomic_helper_crtc_state_reset - reset the CRTC state
* @crtc_state: atomic CRTC state, must not be NULL
* @crtc: CRTC object, must not be NULL
*
* Initializes the newly allocated @crtc_state with default
* values. This is useful for drivers that subclass the CRTC state.
*/
void
__drm_atomic_helper_crtc_state_reset(struct drm_crtc_state *crtc_state,
struct drm_crtc *crtc)
{
crtc_state->crtc = crtc;
}
EXPORT_SYMBOL(__drm_atomic_helper_crtc_state_reset);
/**
* __drm_atomic_helper_crtc_reset - reset state on CRTC
* @crtc: drm CRTC
* @crtc_state: CRTC state to assign
*
* Initializes the newly allocated @crtc_state and assigns it to
* the &drm_crtc->state pointer of @crtc, usually required when
* initializing the drivers or when called from the &drm_crtc_funcs.reset
* hook.
*
* This is useful for drivers that subclass the CRTC state.
*/
void
__drm_atomic_helper_crtc_reset(struct drm_crtc *crtc,
struct drm_crtc_state *crtc_state)
{
if (crtc_state)
__drm_atomic_helper_crtc_state_reset(crtc_state, crtc);
if (drm_dev_has_vblank(crtc->dev))
drm_crtc_vblank_reset(crtc);
crtc->state = crtc_state;
}
EXPORT_SYMBOL(__drm_atomic_helper_crtc_reset);
/**
* drm_atomic_helper_crtc_reset - default &drm_crtc_funcs.reset hook for CRTCs
* @crtc: drm CRTC
*
* Resets the atomic state for @crtc by freeing the state pointer (which might
* be NULL, e.g. at driver load time) and allocating a new empty state object.
*/
void drm_atomic_helper_crtc_reset(struct drm_crtc *crtc)
{
struct drm_crtc_state *crtc_state =
kzalloc(sizeof(*crtc->state), GFP_KERNEL);
if (crtc->state)
crtc->funcs->atomic_destroy_state(crtc, crtc->state);
__drm_atomic_helper_crtc_reset(crtc, crtc_state);
}
EXPORT_SYMBOL(drm_atomic_helper_crtc_reset);
/**
* __drm_atomic_helper_crtc_duplicate_state - copy atomic CRTC state
* @crtc: CRTC object
* @state: atomic CRTC state
*
* Copies atomic state from a CRTC's current state and resets inferred values.
* This is useful for drivers that subclass the CRTC state.
*/
void __drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
memcpy(state, crtc->state, sizeof(*state));
if (state->mode_blob)
drm_property_blob_get(state->mode_blob);
if (state->degamma_lut)
drm_property_blob_get(state->degamma_lut);
if (state->ctm)
drm_property_blob_get(state->ctm);
if (state->gamma_lut)
drm_property_blob_get(state->gamma_lut);
state->mode_changed = false;
state->active_changed = false;
state->planes_changed = false;
state->connectors_changed = false;
state->color_mgmt_changed = false;
state->zpos_changed = false;
state->commit = NULL;
state->event = NULL;
state->async_flip = false;
/* Self refresh should be canceled when a new update is available */
state->active = drm_atomic_crtc_effectively_active(state);
state->self_refresh_active = false;
}
EXPORT_SYMBOL(__drm_atomic_helper_crtc_duplicate_state);
/**
* drm_atomic_helper_crtc_duplicate_state - default state duplicate hook
* @crtc: drm CRTC
*
* Default CRTC state duplicate hook for drivers which don't have their own
* subclassed CRTC state structure.
*/
struct drm_crtc_state *
drm_atomic_helper_crtc_duplicate_state(struct drm_crtc *crtc)
{
struct drm_crtc_state *state;
if (WARN_ON(!crtc->state))
return NULL;
state = kmalloc(sizeof(*state), GFP_KERNEL);
if (state)
__drm_atomic_helper_crtc_duplicate_state(crtc, state);
return state;
}
EXPORT_SYMBOL(drm_atomic_helper_crtc_duplicate_state);
/**
* __drm_atomic_helper_crtc_destroy_state - release CRTC state
* @state: CRTC state object to release
*
* Releases all resources stored in the CRTC state without actually freeing
* the memory of the CRTC state. This is useful for drivers that subclass the
* CRTC state.
*/
void __drm_atomic_helper_crtc_destroy_state(struct drm_crtc_state *state)
{
if (state->commit) {
/*
* In the event that a non-blocking commit returns
* -ERESTARTSYS before the commit_tail work is queued, we will
* have an extra reference to the commit object. Release it, if
* the event has not been consumed by the worker.
*
* state->event may be freed, so we can't directly look at
* state->event->base.completion.
*/
if (state->event && state->commit->abort_completion)
drm_crtc_commit_put(state->commit);
kfree(state->commit->event);
state->commit->event = NULL;
drm_crtc_commit_put(state->commit);
}
drm_property_blob_put(state->mode_blob);
drm_property_blob_put(state->degamma_lut);
drm_property_blob_put(state->ctm);
drm_property_blob_put(state->gamma_lut);
}
EXPORT_SYMBOL(__drm_atomic_helper_crtc_destroy_state);
/**
* drm_atomic_helper_crtc_destroy_state - default state destroy hook
* @crtc: drm CRTC
* @state: CRTC state object to release
*
* Default CRTC state destroy hook for drivers which don't have their own
* subclassed CRTC state structure.
*/
void drm_atomic_helper_crtc_destroy_state(struct drm_crtc *crtc,
struct drm_crtc_state *state)
{
__drm_atomic_helper_crtc_destroy_state(state);
kfree(state);
}
EXPORT_SYMBOL(drm_atomic_helper_crtc_destroy_state);
/**
* __drm_atomic_helper_plane_state_reset - resets plane state to default values
* @plane_state: atomic plane state, must not be NULL
* @plane: plane object, must not be NULL
*
* Initializes the newly allocated @plane_state with default
* values. This is useful for drivers that subclass the CRTC state.
*/
void __drm_atomic_helper_plane_state_reset(struct drm_plane_state *plane_state,
struct drm_plane *plane)
{
plane_state->plane = plane;
plane_state->rotation = DRM_MODE_ROTATE_0;
plane_state->alpha = DRM_BLEND_ALPHA_OPAQUE;
plane_state->pixel_blend_mode = DRM_MODE_BLEND_PREMULTI;
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_state_reset);
/**
* __drm_atomic_helper_plane_reset - reset state on plane
* @plane: drm plane
* @plane_state: plane state to assign
*
* Initializes the newly allocated @plane_state and assigns it to
* the &drm_crtc->state pointer of @plane, usually required when
* initializing the drivers or when called from the &drm_plane_funcs.reset
* hook.
*
* This is useful for drivers that subclass the plane state.
*/
void __drm_atomic_helper_plane_reset(struct drm_plane *plane,
struct drm_plane_state *plane_state)
{
if (plane_state)
__drm_atomic_helper_plane_state_reset(plane_state, plane);
plane->state = plane_state;
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_reset);
/**
* drm_atomic_helper_plane_reset - default &drm_plane_funcs.reset hook for planes
* @plane: drm plane
*
* Resets the atomic state for @plane by freeing the state pointer (which might
* be NULL, e.g. at driver load time) and allocating a new empty state object.
*/
void drm_atomic_helper_plane_reset(struct drm_plane *plane)
{
if (plane->state)
__drm_atomic_helper_plane_destroy_state(plane->state);
kfree(plane->state);
plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL);
if (plane->state)
__drm_atomic_helper_plane_reset(plane, plane->state);
}
EXPORT_SYMBOL(drm_atomic_helper_plane_reset);
/**
* __drm_atomic_helper_plane_duplicate_state - copy atomic plane state
* @plane: plane object
* @state: atomic plane state
*
* Copies atomic state from a plane's current state. This is useful for
* drivers that subclass the plane state.
*/
void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
struct drm_plane_state *state)
{
memcpy(state, plane->state, sizeof(*state));
if (state->fb)
drm_framebuffer_get(state->fb);
state->fence = NULL;
state->commit = NULL;
state->fb_damage_clips = NULL;
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
/**
* drm_atomic_helper_plane_duplicate_state - default state duplicate hook
* @plane: drm plane
*
* Default plane state duplicate hook for drivers which don't have their own
* subclassed plane state structure.
*/
struct drm_plane_state *
drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane)
{
struct drm_plane_state *state;
if (WARN_ON(!plane->state))
return NULL;
state = kmalloc(sizeof(*state), GFP_KERNEL);
if (state)
__drm_atomic_helper_plane_duplicate_state(plane, state);
return state;
}
EXPORT_SYMBOL(drm_atomic_helper_plane_duplicate_state);
/**
* __drm_atomic_helper_plane_destroy_state - release plane state
* @state: plane state object to release
*
* Releases all resources stored in the plane state without actually freeing
* the memory of the plane state. This is useful for drivers that subclass the
* plane state.
*/
void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
{
if (state->fb)
drm_framebuffer_put(state->fb);
if (state->fence)
dma_fence_put(state->fence);
if (state->commit)
drm_crtc_commit_put(state->commit);
drm_property_blob_put(state->fb_damage_clips);
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
/**
* drm_atomic_helper_plane_destroy_state - default state destroy hook
* @plane: drm plane
* @state: plane state object to release
*
* Default plane state destroy hook for drivers which don't have their own
* subclassed plane state structure.
*/
void drm_atomic_helper_plane_destroy_state(struct drm_plane *plane,
struct drm_plane_state *state)
{
__drm_atomic_helper_plane_destroy_state(state);
kfree(state);
}
EXPORT_SYMBOL(drm_atomic_helper_plane_destroy_state);
/**
* __drm_atomic_helper_connector_state_reset - reset the connector state
* @conn_state: atomic connector state, must not be NULL
* @connector: connectotr object, must not be NULL
*
* Initializes the newly allocated @conn_state with default
* values. This is useful for drivers that subclass the connector state.
*/
void
__drm_atomic_helper_connector_state_reset(struct drm_connector_state *conn_state,
struct drm_connector *connector)
{
conn_state->connector = connector;
}
EXPORT_SYMBOL(__drm_atomic_helper_connector_state_reset);
/**
* __drm_atomic_helper_connector_reset - reset state on connector
* @connector: drm connector
* @conn_state: connector state to assign
*
* Initializes the newly allocated @conn_state and assigns it to
* the &drm_connector->state pointer of @connector, usually required when
* initializing the drivers or when called from the &drm_connector_funcs.reset
* hook.
*
* This is useful for drivers that subclass the connector state.
*/
void
__drm_atomic_helper_connector_reset(struct drm_connector *connector,
struct drm_connector_state *conn_state)
{
if (conn_state)
__drm_atomic_helper_connector_state_reset(conn_state, connector);
connector->state = conn_state;
}
EXPORT_SYMBOL(__drm_atomic_helper_connector_reset);
/**
* drm_atomic_helper_connector_reset - default &drm_connector_funcs.reset hook for connectors
* @connector: drm connector
*
* Resets the atomic state for @connector by freeing the state pointer (which
* might be NULL, e.g. at driver load time) and allocating a new empty state
* object.
*/
void drm_atomic_helper_connector_reset(struct drm_connector *connector)
{
struct drm_connector_state *conn_state =
kzalloc(sizeof(*conn_state), GFP_KERNEL);
if (connector->state)
__drm_atomic_helper_connector_destroy_state(connector->state);
kfree(connector->state);
__drm_atomic_helper_connector_reset(connector, conn_state);
}
EXPORT_SYMBOL(drm_atomic_helper_connector_reset);
/**
* drm_atomic_helper_connector_tv_reset - Resets TV connector properties
* @connector: DRM connector
*
* Resets the TV-related properties attached to a connector.
*/
void drm_atomic_helper_connector_tv_reset(struct drm_connector *connector)
{
struct drm_cmdline_mode *cmdline = &connector->cmdline_mode;
struct drm_connector_state *state = connector->state;
state->tv.margins.left = cmdline->tv_margins.left;
state->tv.margins.right = cmdline->tv_margins.right;
state->tv.margins.top = cmdline->tv_margins.top;
state->tv.margins.bottom = cmdline->tv_margins.bottom;
}
EXPORT_SYMBOL(drm_atomic_helper_connector_tv_reset);
/**
* __drm_atomic_helper_connector_duplicate_state - copy atomic connector state
* @connector: connector object
* @state: atomic connector state
*
* Copies atomic state from a connector's current state. This is useful for
* drivers that subclass the connector state.
*/
void
__drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector,
struct drm_connector_state *state)
{
memcpy(state, connector->state, sizeof(*state));
if (state->crtc)
drm_connector_get(connector);
state->commit = NULL;
if (state->hdr_output_metadata)
drm_property_blob_get(state->hdr_output_metadata);
/* Don't copy over a writeback job, they are used only once */
state->writeback_job = NULL;
}
EXPORT_SYMBOL(__drm_atomic_helper_connector_duplicate_state);
/**
* drm_atomic_helper_connector_duplicate_state - default state duplicate hook
* @connector: drm connector
*
* Default connector state duplicate hook for drivers which don't have their own
* subclassed connector state structure.
*/
struct drm_connector_state *
drm_atomic_helper_connector_duplicate_state(struct drm_connector *connector)
{
struct drm_connector_state *state;
if (WARN_ON(!connector->state))
return NULL;
state = kmalloc(sizeof(*state), GFP_KERNEL);
if (state)
__drm_atomic_helper_connector_duplicate_state(connector, state);
return state;
}
EXPORT_SYMBOL(drm_atomic_helper_connector_duplicate_state);
/**
* __drm_atomic_helper_connector_destroy_state - release connector state
* @state: connector state object to release
*
* Releases all resources stored in the connector state without actually
* freeing the memory of the connector state. This is useful for drivers that
* subclass the connector state.
*/
void
__drm_atomic_helper_connector_destroy_state(struct drm_connector_state *state)
{
if (state->crtc)
drm_connector_put(state->connector);
if (state->commit)
drm_crtc_commit_put(state->commit);
if (state->writeback_job)
drm_writeback_cleanup_job(state->writeback_job);
drm_property_blob_put(state->hdr_output_metadata);
}
EXPORT_SYMBOL(__drm_atomic_helper_connector_destroy_state);
/**
* drm_atomic_helper_connector_destroy_state - default state destroy hook
* @connector: drm connector
* @state: connector state object to release
*
* Default connector state destroy hook for drivers which don't have their own
* subclassed connector state structure.
*/
void drm_atomic_helper_connector_destroy_state(struct drm_connector *connector,
struct drm_connector_state *state)
{
__drm_atomic_helper_connector_destroy_state(state);
kfree(state);
}
EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state);
/**
* __drm_atomic_helper_private_duplicate_state - copy atomic private state
* @obj: CRTC object
* @state: new private object state
*
* Copies atomic state from a private objects's current state and resets inferred values.
* This is useful for drivers that subclass the private state.
*/
void __drm_atomic_helper_private_obj_duplicate_state(struct drm_private_obj *obj,
struct drm_private_state *state)
{
memcpy(state, obj->state, sizeof(*state));
}
EXPORT_SYMBOL(__drm_atomic_helper_private_obj_duplicate_state);
/**
* __drm_atomic_helper_bridge_duplicate_state() - Copy atomic bridge state
* @bridge: bridge object
* @state: atomic bridge state
*
* Copies atomic state from a bridge's current state and resets inferred values.
* This is useful for drivers that subclass the bridge state.
*/
void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge,
struct drm_bridge_state *state)
{
__drm_atomic_helper_private_obj_duplicate_state(&bridge->base,
&state->base);
state->bridge = bridge;
}
EXPORT_SYMBOL(__drm_atomic_helper_bridge_duplicate_state);
/**
* drm_atomic_helper_bridge_duplicate_state() - Duplicate a bridge state object
* @bridge: bridge object
*
* Allocates a new bridge state and initializes it with the current bridge
* state values. This helper is meant to be used as a bridge
* &drm_bridge_funcs.atomic_duplicate_state hook for bridges that don't
* subclass the bridge state.
*/
struct drm_bridge_state *
drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge)
{
struct drm_bridge_state *new;
if (WARN_ON(!bridge->base.state))
return NULL;
new = kzalloc(sizeof(*new), GFP_KERNEL);
if (new)
__drm_atomic_helper_bridge_duplicate_state(bridge, new);
return new;
}
EXPORT_SYMBOL(drm_atomic_helper_bridge_duplicate_state);
/**
* drm_atomic_helper_bridge_destroy_state() - Destroy a bridge state object
* @bridge: the bridge this state refers to
* @state: bridge state to destroy
*
* Destroys a bridge state previously created by
* &drm_atomic_helper_bridge_reset() or
* &drm_atomic_helper_bridge_duplicate_state(). This helper is meant to be
* used as a bridge &drm_bridge_funcs.atomic_destroy_state hook for bridges
* that don't subclass the bridge state.
*/
void drm_atomic_helper_bridge_destroy_state(struct drm_bridge *bridge,
struct drm_bridge_state *state)
{
kfree(state);
}
EXPORT_SYMBOL(drm_atomic_helper_bridge_destroy_state);
/**
* __drm_atomic_helper_bridge_reset() - Initialize a bridge state to its
* default
* @bridge: the bridge this state refers to
* @state: bridge state to initialize
*
* Initializes the bridge state to default values. This is meant to be called
* by the bridge &drm_bridge_funcs.atomic_reset hook for bridges that subclass
* the bridge state.
*/
void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge,
struct drm_bridge_state *state)
{
memset(state, 0, sizeof(*state));
state->bridge = bridge;
}
EXPORT_SYMBOL(__drm_atomic_helper_bridge_reset);
/**
* drm_atomic_helper_bridge_reset() - Allocate and initialize a bridge state
* to its default
* @bridge: the bridge this state refers to
*
* Allocates the bridge state and initializes it to default values. This helper
* is meant to be used as a bridge &drm_bridge_funcs.atomic_reset hook for
* bridges that don't subclass the bridge state.
*/
struct drm_bridge_state *
drm_atomic_helper_bridge_reset(struct drm_bridge *bridge)
{
struct drm_bridge_state *bridge_state;
bridge_state = kzalloc(sizeof(*bridge_state), GFP_KERNEL);
if (!bridge_state)
return ERR_PTR(-ENOMEM);
__drm_atomic_helper_bridge_reset(bridge, bridge_state);
return bridge_state;
}
EXPORT_SYMBOL(drm_atomic_helper_bridge_reset);