Hi Jim,
On 6/23/23 19:23, Jim Shargo wrote:
This change supports multiple CRTCs, encoders, connectors instead of one
of each per device.
Since ConfigFS-based devices will support multiple crtcs, it's useful to
move all of the writeback/composition data from being per-"output" to
being per-CRTC.
Since there's still only ever one CRTC, this should be a no-op refactor.
Signed-off-by: Jim Shargo <jshargo@xxxxxxxxxxxx>
---
drivers/gpu/drm/vkms/vkms_composer.c | 28 +++---
drivers/gpu/drm/vkms/vkms_crtc.c | 95 +++++++++++---------
drivers/gpu/drm/vkms/vkms_drv.c | 14 +--
drivers/gpu/drm/vkms/vkms_drv.h | 65 +++++++++-----
drivers/gpu/drm/vkms/vkms_output.c | 123 ++++++++++++++++++--------
drivers/gpu/drm/vkms/vkms_plane.c | 44 ++++++---
drivers/gpu/drm/vkms/vkms_writeback.c | 26 +++---
7 files changed, 252 insertions(+), 143 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 1636ce3a79f9..75fa42e0ec07 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -230,13 +230,13 @@ void vkms_composer_worker(struct work_struct *work)
composer_work);
struct drm_crtc *crtc = crtc_state->base.crtc;
struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
- struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
bool crc_pending, wb_pending;
u64 frame_start, frame_end;
u32 crc32 = 0;
int ret;
- spin_lock_irq(&out->composer_lock);
+ spin_lock_irq(&vkms_crtc->composer_lock);
frame_start = crtc_state->frame_start;
frame_end = crtc_state->frame_end;
crc_pending = crtc_state->crc_pending;
@@ -244,7 +244,7 @@ void vkms_composer_worker(struct work_struct *work)
crtc_state->frame_start = 0;
crtc_state->frame_end = 0;
crtc_state->crc_pending = false;
- spin_unlock_irq(&out->composer_lock);
+ spin_unlock_irq(&vkms_crtc->composer_lock);
/*
* We raced with the vblank hrtimer and previous work already computed
@@ -262,10 +262,10 @@ void vkms_composer_worker(struct work_struct *work)
return;
if (wb_pending) {
- drm_writeback_signal_completion(&out->wb_connector, 0);
- spin_lock_irq(&out->composer_lock);
+ drm_writeback_signal_completion(&vkms_crtc->wb_connector, 0);
+ spin_lock_irq(&vkms_crtc->composer_lock);
crtc_state->wb_pending = false;
- spin_unlock_irq(&out->composer_lock);
+ spin_unlock_irq(&vkms_crtc->composer_lock);
}
/*
@@ -315,25 +315,25 @@ int vkms_verify_crc_source(struct drm_crtc *crtc, const char *src_name,
return 0;
}
-void vkms_set_composer(struct vkms_output *out, bool enabled)
+void vkms_set_composer(struct vkms_crtc *vkms_crtc, bool enabled)
{
bool old_enabled;
if (enabled)
- drm_crtc_vblank_get(&out->crtc);
+ drm_crtc_vblank_get(&vkms_crtc->base);
- spin_lock_irq(&out->lock);
- old_enabled = out->composer_enabled;
- out->composer_enabled = enabled;
- spin_unlock_irq(&out->lock);
+ spin_lock_irq(&vkms_crtc->lock);
+ old_enabled = vkms_crtc->composer_enabled;
+ vkms_crtc->composer_enabled = enabled;
+ spin_unlock_irq(&vkms_crtc->lock);
if (old_enabled)
- drm_crtc_vblank_put(&out->crtc);
+ drm_crtc_vblank_put(&vkms_crtc->base);
}
int vkms_set_crc_source(struct drm_crtc *crtc, const char *src_name)
{
- struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+ struct vkms_crtc *out = drm_crtc_to_vkms_crtc(crtc);
bool enabled = false;
int ret = 0;
diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index 515f6772b866..d91e49c53adc 100644
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -11,35 +11,34 @@
static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
{
- struct vkms_output *output = container_of(timer, struct vkms_output,
- vblank_hrtimer);
- struct drm_crtc *crtc = &output->crtc;
+ struct vkms_crtc *vkms_crtc = timer_to_vkms_crtc(timer);
+ struct drm_crtc *crtc = &vkms_crtc->base;
struct vkms_crtc_state *state;
u64 ret_overrun;
bool ret, fence_cookie;
fence_cookie = dma_fence_begin_signalling();
- ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
- output->period_ns);
+ ret_overrun = hrtimer_forward_now(&vkms_crtc->vblank_hrtimer,
+ vkms_crtc->period_ns);
if (ret_overrun != 1)
pr_warn("%s: vblank timer overrun\n", __func__);
- spin_lock(&output->lock);
+ spin_lock(&vkms_crtc->lock);
ret = drm_crtc_handle_vblank(crtc);
if (!ret)
DRM_ERROR("vkms failure on handling vblank");
- state = output->composer_state;
- spin_unlock(&output->lock);
+ state = vkms_crtc->composer_state;
+ spin_unlock(&vkms_crtc->lock);
- if (state && output->composer_enabled) {
+ if (state && vkms_crtc->composer_enabled) {
u64 frame = drm_crtc_accurate_vblank_count(crtc);
/* update frame_start only if a queued vkms_composer_worker()
* has read the data
*/
- spin_lock(&output->composer_lock);
+ spin_lock(&vkms_crtc->composer_lock);
if (!state->crc_pending)
state->frame_start = frame;
else
@@ -47,9 +46,10 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
state->frame_start, frame);
state->frame_end = frame;
state->crc_pending = true;
- spin_unlock(&output->composer_lock);
+ spin_unlock(&vkms_crtc->composer_lock);
- ret = queue_work(output->composer_workq, &state->composer_work);
+ ret = queue_work(vkms_crtc->composer_workq,
+ &state->composer_work);
if (!ret)
DRM_DEBUG_DRIVER("Composer worker already queued\n");
}
@@ -62,25 +62,27 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
static int vkms_enable_vblank(struct drm_crtc *crtc)
{
struct drm_device *dev = crtc->dev;
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
unsigned int pipe = drm_crtc_index(crtc);
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
- struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
drm_calc_timestamping_constants(crtc, &crtc->mode);
- hrtimer_init(&out->vblank_hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- out->vblank_hrtimer.function = &vkms_vblank_simulate;
- out->period_ns = ktime_set(0, vblank->framedur_ns);
- hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_REL);
+ hrtimer_init(&vkms_crtc->vblank_hrtimer, CLOCK_MONOTONIC,
+ HRTIMER_MODE_REL);
+ vkms_crtc->vblank_hrtimer.function = &vkms_vblank_simulate;
+ vkms_crtc->period_ns = ktime_set(0, vblank->framedur_ns);
+ hrtimer_start(&vkms_crtc->vblank_hrtimer, vkms_crtc->period_ns,
+ HRTIMER_MODE_REL);
return 0;
}
static void vkms_disable_vblank(struct drm_crtc *crtc)
{
- struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
- hrtimer_cancel(&out->vblank_hrtimer);
+ hrtimer_cancel(&vkms_crtc->vblank_hrtimer);
}
static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
@@ -88,9 +90,8 @@ static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
bool in_vblank_irq)
{
struct drm_device *dev = crtc->dev;
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
unsigned int pipe = crtc->index;
- struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
- struct vkms_output *output = &vkmsdev->output;
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
if (!READ_ONCE(vblank->enabled)) {
@@ -98,7 +99,7 @@ static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
return true;
}
- *vblank_time = READ_ONCE(output->vblank_hrtimer.node.expires);
+ *vblank_time = READ_ONCE(vkms_crtc->vblank_hrtimer.node.expires);
if (WARN_ON(*vblank_time == vblank->time))
return true;
@@ -110,7 +111,7 @@ static bool vkms_get_vblank_timestamp(struct drm_crtc *crtc,
* the vblank core expects. Therefore we need to always correct the
* timestampe by one frame.
*/
- *vblank_time -= output->period_ns;
+ *vblank_time -= vkms_crtc->period_ns;
return true;
}
@@ -236,18 +237,18 @@ static void vkms_crtc_atomic_disable(struct drm_crtc *crtc,
static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
struct drm_atomic_state *state)
{
- struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
/* This lock is held across the atomic commit to block vblank timer
* from scheduling vkms_composer_worker until the composer is updated
*/
- spin_lock_irq(&vkms_output->lock);
+ spin_lock_irq(&vkms_crtc->lock);
}
static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
struct drm_atomic_state *state)
{
- struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
+ struct vkms_crtc *vkms_crtc = drm_crtc_to_vkms_crtc(crtc);
if (crtc->state->event) {
spin_lock(&crtc->dev->event_lock);
@@ -262,9 +263,9 @@ static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
crtc->state->event = NULL;
}
- vkms_output->composer_state = to_vkms_crtc_state(crtc->state);
+ vkms_crtc->composer_state = to_vkms_crtc_state(crtc->state);
- spin_unlock_irq(&vkms_output->lock);
+ spin_unlock_irq(&vkms_crtc->lock);
}
static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
@@ -275,27 +276,41 @@ static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
.atomic_disable = vkms_crtc_atomic_disable,
};
-int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
- struct drm_plane *primary, struct drm_plane *cursor)
+struct vkms_crtc *vkms_crtc_init(struct vkms_device *vkmsdev,
+ struct drm_plane *primary,
+ struct drm_plane *cursor)
{
- struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc);
+ struct drm_device *dev = &vkmsdev->drm;
+ struct vkms_crtc *vkms_crtc;
int ret;
- ret = drmm_crtc_init_with_planes(dev, crtc, primary, cursor,
+ if (vkmsdev->output.num_crtcs >= VKMS_MAX_OUTPUT_OBJECTS) {
+ return ERR_PTR(-ENOMEM);
+ }
+ vkms_crtc = &vkmsdev->output.crtcs[vkmsdev->output.num_crtcs++];
+
+ ret = drmm_crtc_init_with_planes(dev, &vkms_crtc->base, primary, cursor,
&vkms_crtc_funcs, NULL);
if (ret) {
DRM_ERROR("Failed to init CRTC\n");
- return ret;
+ goto out_error;
}
- drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
+ drm_crtc_helper_add(&vkms_crtc->base, &vkms_crtc_helper_funcs);
- spin_lock_init(&vkms_out->lock);
- spin_lock_init(&vkms_out->composer_lock);
+ spin_lock_init(&vkms_crtc->lock);
+ spin_lock_init(&vkms_crtc->composer_lock);
- vkms_out->composer_workq = alloc_ordered_workqueue("vkms_composer", 0);
- if (!vkms_out->composer_workq)
- return -ENOMEM;
+ vkms_crtc->composer_workq = alloc_ordered_workqueue("vkms_composer", 0);
+ if (!vkms_crtc->composer_workq) {
+ ret = -ENOMEM;
+ goto out_error;
+ }
+
+ return vkms_crtc;
- return ret;
+out_error:
+ memset(vkms_crtc, 0, sizeof(*vkms_crtc));
+ vkmsdev->output.num_crtcs -= 1;
+ return ERR_PTR(ret);
}
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index f07454fff046..aa2bee82b757 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -57,8 +57,8 @@ static void vkms_release(struct drm_device *dev)
{
struct vkms_device *vkms = drm_device_to_vkms_device(dev);
- if (vkms->output.composer_workq)
- destroy_workqueue(vkms->output.composer_workq);
+ for (int i = 0; i < vkms->output.num_crtcs; i++)
+ destroy_workqueue(vkms->output.crtcs[i].composer_workq);
Is there no need to check if vkms->output.crtcs[i].composer_workq is
NULL?
}
static void vkms_atomic_commit_tail(struct drm_atomic_state *old_state)
@@ -185,15 +185,15 @@ static int vkms_platform_probe(struct platform_device *pdev)
goto out_release_group;
}
- ret = drm_vblank_init(&vkms_device->drm, 1);
+ ret = vkms_modeset_init(vkms_device);
if (ret) {
- DRM_ERROR("Failed to vblank\n");
+ DRM_ERROR("Unable to initialize modesetting\n");
goto out_release_group;
}
- ret = vkms_modeset_init(vkms_device);
+ ret = drm_vblank_init(&vkms_device->drm, vkms_device->output.num_crtcs);
if (ret) {
- DRM_ERROR("Unable to initialize modesetting\n");
+ DRM_ERROR("Failed to vblank\n");
goto out_release_group;
}
@@ -202,7 +202,7 @@ static int vkms_platform_probe(struct platform_device *pdev)
ret = drm_dev_register(&vkms_device->drm, 0);
if (ret) {
- DRM_ERROR("Unable to register device\n");
+ DRM_ERROR("Unable to register device with id %d\n", pdev->id);
I believe this belongs to the first patch.
return ret;
}
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index e87c8aea6fb3..4c3274838ec7 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -23,6 +23,9 @@
#define NUM_OVERLAY_PLANES 8
+#define VKMS_MAX_OUTPUT_OBJECTS 16
+#define VKMS_MAX_PLANES (3 * VKMS_MAX_OUTPUT_OBJECTS)
+
struct vkms_frame_info {
struct drm_framebuffer *fb;
struct drm_rect src, dst;
@@ -65,6 +68,25 @@ struct vkms_plane {
struct drm_plane base;
};
+struct vkms_crtc {
+ struct drm_crtc base;
+
+ struct drm_writeback_connector wb_connector;
+ struct hrtimer vblank_hrtimer;
+ ktime_t period_ns;
+ struct drm_pending_vblank_event *event;
+ /* ordered wq for composer_work */
+ struct workqueue_struct *composer_workq;
+ /* protects concurrent access to composer */
+ spinlock_t lock;
+
+ /* protected by @lock */
+ bool composer_enabled;
+ struct vkms_crtc_state *composer_state;
+
+ spinlock_t composer_lock;
+};
+
/**
* vkms_crtc_state - Driver specific CRTC state
* @base: base CRTC state
[...]
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index e5c625ab8e3e..f69621822c1b 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -8,6 +8,8 @@
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_plane.h>
+#include <drm/drm_plane_helper.h>
#include "vkms_drv.h"
#include "vkms_formats.h"
@@ -65,6 +67,20 @@ static void vkms_plane_destroy_state(struct drm_plane *plane,
kfree(vkms_state);
}
+static void vkms_plane_destroy(struct drm_plane *plane)
+{
+ struct vkms_plane *vkms_plane =
+ container_of(plane, struct vkms_plane, base);
+
+ if (plane->state) {
+ vkms_plane_destroy_state(plane, plane->state);
+ plane->state = NULL;
+ }
+
+ drm_plane_cleanup(plane);
+ memset(vkms_plane, 0, sizeof(struct vkms_plane));
+}
+
static void vkms_plane_reset(struct drm_plane *plane)
{
struct vkms_plane_state *vkms_state;
@@ -84,11 +100,12 @@ static void vkms_plane_reset(struct drm_plane *plane)
}
static const struct drm_plane_funcs vkms_plane_funcs = {
- .update_plane = drm_atomic_helper_update_plane,
- .disable_plane = drm_atomic_helper_disable_plane,
- .reset = vkms_plane_reset,
I believe that there is no need to change this lines.
+ .update_plane = drm_atomic_helper_update_plane,
+ .disable_plane = drm_atomic_helper_disable_plane,
+ .destroy = vkms_plane_destroy,
+ .reset = vkms_plane_reset,
.atomic_duplicate_state = vkms_plane_duplicate_state,
- .atomic_destroy_state = vkms_plane_destroy_state,
+ .atomic_destroy_state = vkms_plane_destroy_state,
};
static void vkms_plane_atomic_update(struct drm_plane *plane,
@@ -198,17 +215,22 @@ static const struct drm_plane_helper_funcs vkms_plane_helper_funcs = {
};
struct vkms_plane *vkms_plane_init(struct vkms_device *vkmsdev,
- enum drm_plane_type type, int index)
+ enum drm_plane_type type)
{
struct drm_device *dev = &vkmsdev->drm;
+ struct vkms_output *output = &vkmsdev->output;
struct vkms_plane *plane;
+ int ret;
- plane = drmm_universal_plane_alloc(dev, struct vkms_plane, base, 1 << index,
- &vkms_plane_funcs,
- vkms_formats, ARRAY_SIZE(vkms_formats),
- NULL, type, NULL);
- if (IS_ERR(plane))
- return plane;
+ if (output->num_planes >= VKMS_MAX_PLANES)
+ return ERR_PTR(-ENOMEM);
+
+ plane = &output->planes[output->num_planes++];
+ ret = drm_universal_plane_init(dev, &plane->base, 0, &vkms_plane_funcs,
+ vkms_formats, ARRAY_SIZE(vkms_formats),
+ NULL, type, NULL);
Wouldn't be possible to use drmm_universal_plane_alloc?
Best Regards,
- Maíra
+ if (ret)
+ return ERR_PTR(ret);
drm_plane_helper_add(&plane->base, &vkms_plane_helper_funcs);
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 84a51cd281b9..b90bcbd0a0e0 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0+
#include <linux/iosys-map.h>
+#include <linux/kernel.h>
#include <drm/drm_atomic.h>
#include <drm/drm_edid.h>
@@ -101,7 +102,8 @@ static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
struct drm_writeback_job *job)
{
struct vkms_writeback_job *vkmsjob = job->priv;
- struct vkms_device *vkmsdev;
+ struct vkms_crtc *vkms_crtc =
+ container_of(connector, struct vkms_crtc, wb_connector);
if (!job->fb)
return;
@@ -110,8 +112,7 @@ static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
drm_framebuffer_put(vkmsjob->wb_frame_info.fb);
- vkmsdev = drm_device_to_vkms_device(job->fb->dev);
- vkms_set_composer(&vkmsdev->output, false);
+ vkms_set_composer(vkms_crtc, false);
kfree(vkmsjob);
}
@@ -120,11 +121,11 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
{
struct drm_connector_state *connector_state = drm_atomic_get_new_connector_state(state,
conn);
- struct vkms_device *vkmsdev = drm_device_to_vkms_device(conn->dev);
- struct vkms_output *output = &vkmsdev->output;
- struct drm_writeback_connector *wb_conn = &output->wb_connector;
+ struct vkms_crtc *vkms_crtc =
+ drm_crtc_to_vkms_crtc(connector_state->crtc);
+ struct drm_writeback_connector *wb_conn = &vkms_crtc->wb_connector;
struct drm_connector_state *conn_state = wb_conn->base.state;
- struct vkms_crtc_state *crtc_state = output->composer_state;
+ struct vkms_crtc_state *crtc_state = vkms_crtc->composer_state;
struct drm_framebuffer *fb = connector_state->writeback_job->fb;
u16 crtc_height = crtc_state->base.crtc->mode.vdisplay;
u16 crtc_width = crtc_state->base.crtc->mode.hdisplay;
@@ -135,18 +136,18 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
if (!conn_state)
return;
- vkms_set_composer(&vkmsdev->output, true);
+ vkms_set_composer(vkms_crtc, true);
active_wb = conn_state->writeback_job->priv;
wb_frame_info = &active_wb->wb_frame_info;
- spin_lock_irq(&output->composer_lock);
+ spin_lock_irq(&vkms_crtc->composer_lock);
crtc_state->active_writeback = active_wb;
wb_frame_info->offset = fb->offsets[0];
wb_frame_info->pitch = fb->pitches[0];
wb_frame_info->cpp = fb->format->cpp[0];
crtc_state->wb_pending = true;
- spin_unlock_irq(&output->composer_lock);
+ spin_unlock_irq(&vkms_crtc->composer_lock);
drm_writeback_queue_job(wb_conn, connector_state);
active_wb->wb_write = get_line_to_frame_function(wb_format);
drm_rect_init(&wb_frame_info->src, 0, 0, crtc_width, crtc_height);
@@ -160,9 +161,10 @@ static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = {
.atomic_commit = vkms_wb_atomic_commit,
};
-int vkms_enable_writeback_connector(struct vkms_device *vkmsdev)
+int vkms_enable_writeback_connector(struct vkms_device *vkmsdev,
+ struct vkms_crtc *vkms_crtc)
{
- struct drm_writeback_connector *wb = &vkmsdev->output.wb_connector;
+ struct drm_writeback_connector *wb = &vkms_crtc->wb_connector;
drm_connector_helper_add(&wb->base, &vkms_wb_conn_helper_funcs);
