From 72ebc18b34993777bd6473be36cd63f37b3574ba Mon Sep 17 00:00:00 2001
From: Philipp Stanner <pstanner@redhat.com>
Date: Wed, 5 Mar 2025 14:05:51 +0100
Subject: [PATCH 01/16] drm/sched: Document run_job() refcount hazard

drm_sched_backend_ops.run_job() returns a dma_fence for the scheduler.
That fence is signalled by the driver once the hardware completed the
associated job. The scheduler does not increment the reference count on
that fence, but implicitly expects to inherit this fence from run_job().

This is relatively subtle and prone to misunderstandings.

This implies that, to keep a reference for itself, a driver needs to
call dma_fence_get() in addition to dma_fence_init() in that callback.

It's further complicated by the fact that the scheduler even decrements
the refcount in drm_sched_run_job_work() since it created a new
reference in drm_sched_fence_scheduled(). It does, however, still use
its pointer to the fence after calling dma_fence_put() - which is safe
because of the aforementioned new reference, but actually still violates
the refcounting rules.

Move the call to dma_fence_put() to the position behind the last usage
of the fence.

Suggested-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250305130551.136682-4-phasta@kernel.org
---
 drivers/gpu/drm/scheduler/sched_main.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index bfea608a7106..53e6aec37b46 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -1220,20 +1220,23 @@ static void drm_sched_run_job_work(struct work_struct *w)
 	drm_sched_job_begin(sched_job);
 
 	trace_drm_run_job(sched_job, entity);
+	/*
+	 * The run_job() callback must by definition return a fence whose
+	 * refcount has been incremented for the scheduler already.
+	 */
 	fence = sched->ops->run_job(sched_job);
 	complete_all(&entity->entity_idle);
 	drm_sched_fence_scheduled(s_fence, fence);
 
 	if (!IS_ERR_OR_NULL(fence)) {
-		/* Drop for original kref_init of the fence */
-		dma_fence_put(fence);
-
 		r = dma_fence_add_callback(fence, &sched_job->cb,
 					   drm_sched_job_done_cb);
 		if (r == -ENOENT)
 			drm_sched_job_done(sched_job, fence->error);
 		else if (r)
 			DRM_DEV_ERROR(sched->dev, "fence add callback failed (%d)\n", r);
+
+		dma_fence_put(fence);
 	} else {
 		drm_sched_job_done(sched_job, IS_ERR(fence) ?
 				   PTR_ERR(fence) : 0);
-- 
2.51.0


From 2eeed61db4550171a32854e4d3fdf974b749c214 Mon Sep 17 00:00:00 2001
From: Philipp Stanner <phasta@kernel.org>
Date: Wed, 5 Mar 2025 14:05:52 +0100
Subject: [PATCH 02/16] drm/sched: Update timedout_job()'s documentation

drm_sched_backend_ops.timedout_job()'s documentation is outdated. It
mentions the deprecated function drm_sched_resubmit_jobs(). Furthermore,
it does not point out the important distinction between hardware and
firmware schedulers.

Since firmware schedulers typically only use one entity per scheduler,
timeout handling is significantly more simple because the entity the
faulted job came from can just be killed without affecting innocent
processes.

Update the documentation with that distinction and other details.

Reformat the docstring to work to a unified style with the other
handles.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250305130551.136682-5-phasta@kernel.org
---
 include/drm/gpu_scheduler.h | 78 ++++++++++++++++++++++---------------
 1 file changed, 47 insertions(+), 31 deletions(-)

diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 6381baae8024..1a7e377d4cbb 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -383,8 +383,15 @@ struct drm_sched_job {
 	struct xarray			dependencies;
 };
 
+/**
+ * enum drm_gpu_sched_stat - the scheduler's status
+ *
+ * @DRM_GPU_SCHED_STAT_NONE: Reserved. Do not use.
+ * @DRM_GPU_SCHED_STAT_NOMINAL: Operation succeeded.
+ * @DRM_GPU_SCHED_STAT_ENODEV: Error: Device is not available anymore.
+ */
 enum drm_gpu_sched_stat {
-	DRM_GPU_SCHED_STAT_NONE, /* Reserve 0 */
+	DRM_GPU_SCHED_STAT_NONE,
 	DRM_GPU_SCHED_STAT_NOMINAL,
 	DRM_GPU_SCHED_STAT_ENODEV,
 };
@@ -447,43 +454,52 @@ struct drm_sched_backend_ops {
 	 * @timedout_job: Called when a job has taken too long to execute,
 	 * to trigger GPU recovery.
 	 *
-	 * This method is called in a workqueue context.
+	 * @sched_job: The job that has timed out
+	 *
+	 * Drivers typically issue a reset to recover from GPU hangs.
+	 * This procedure looks very different depending on whether a firmware
+	 * or a hardware scheduler is being used.
+	 *
+	 * For a FIRMWARE SCHEDULER, each ring has one scheduler, and each
+	 * scheduler has one entity. Hence, the steps taken typically look as
+	 * follows:
 	 *
-	 * Drivers typically issue a reset to recover from GPU hangs, and this
-	 * procedure usually follows the following workflow:
+	 * 1. Stop the scheduler using drm_sched_stop(). This will pause the
+	 *    scheduler workqueues and cancel the timeout work, guaranteeing
+	 *    that nothing is queued while the ring is being removed.
+	 * 2. Remove the ring. The firmware will make sure that the
+	 *    corresponding parts of the hardware are resetted, and that other
+	 *    rings are not impacted.
+	 * 3. Kill the entity and the associated scheduler.
 	 *
-	 * 1. Stop the scheduler using drm_sched_stop(). This will park the
-	 *    scheduler thread and cancel the timeout work, guaranteeing that
-	 *    nothing is queued while we reset the hardware queue
-	 * 2. Try to gracefully stop non-faulty jobs (optional)
-	 * 3. Issue a GPU reset (driver-specific)
-	 * 4. Re-submit jobs using drm_sched_resubmit_jobs()
-	 * 5. Restart the scheduler using drm_sched_start(). At that point, new
-	 *    jobs can be queued, and the scheduler thread is unblocked
+	 *
+	 * For a HARDWARE SCHEDULER, a scheduler instance schedules jobs from
+	 * one or more entities to one ring. This implies that all entities
+	 * associated with the affected scheduler cannot be torn down, because
+	 * this would effectively also affect innocent userspace processes which
+	 * did not submit faulty jobs (for example).
+	 *
+	 * Consequently, the procedure to recover with a hardware scheduler
+	 * should look like this:
+	 *
+	 * 1. Stop all schedulers impacted by the reset using drm_sched_stop().
+	 * 2. Kill the entity the faulty job stems from.
+	 * 3. Issue a GPU reset on all faulty rings (driver-specific).
+	 * 4. Re-submit jobs on all schedulers impacted by re-submitting them to
+	 *    the entities which are still alive.
+	 * 5. Restart all schedulers that were stopped in step #1 using
+	 *    drm_sched_start().
 	 *
 	 * Note that some GPUs have distinct hardware queues but need to reset
 	 * the GPU globally, which requires extra synchronization between the
-	 * timeout handler of the different &drm_gpu_scheduler. One way to
-	 * achieve this synchronization is to create an ordered workqueue
-	 * (using alloc_ordered_workqueue()) at the driver level, and pass this
-	 * queue to drm_sched_init(), to guarantee that timeout handlers are
-	 * executed sequentially. The above workflow needs to be slightly
-	 * adjusted in that case:
-	 *
-	 * 1. Stop all schedulers impacted by the reset using drm_sched_stop()
-	 * 2. Try to gracefully stop non-faulty jobs on all queues impacted by
-	 *    the reset (optional)
-	 * 3. Issue a GPU reset on all faulty queues (driver-specific)
-	 * 4. Re-submit jobs on all schedulers impacted by the reset using
-	 *    drm_sched_resubmit_jobs()
-	 * 5. Restart all schedulers that were stopped in step #1 using
-	 *    drm_sched_start()
+	 * timeout handlers of different schedulers. One way to achieve this
+	 * synchronization is to create an ordered workqueue (using
+	 * alloc_ordered_workqueue()) at the driver level, and pass this queue
+	 * as drm_sched_init()'s @timeout_wq parameter. This will guarantee
+	 * that timeout handlers are executed sequentially.
 	 *
-	 * Return DRM_GPU_SCHED_STAT_NOMINAL, when all is normal,
-	 * and the underlying driver has started or completed recovery.
+	 * Return: The scheduler's status, defined by &enum drm_gpu_sched_stat
 	 *
-	 * Return DRM_GPU_SCHED_STAT_ENODEV, if the device is no longer
-	 * available, i.e. has been unplugged.
 	 */
 	enum drm_gpu_sched_stat (*timedout_job)(struct drm_sched_job *sched_job);
 
-- 
2.51.0


From fa0af721bd1f983c5c9c109815a154bd1cb29c75 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>
Date: Wed, 29 Jan 2025 16:28:48 +0100
Subject: [PATCH 03/16] drm/ttm: test private resv obj on release/destroy
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Test the fences in the private dma_resv object instead of the pointer to
a potentially shared dma_resv object.

This only matters for imported BOs with an SG table since those don't
get their dma_resv pointer replaced on release.

Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: James Zhu <James.Zhu@amd.com>
Reviewed-by: James Zhu <James.Zhu@amd.com>
Tested-by: James Zhu <James.Zhu@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250129152849.15777-1-christian.koenig@amd.com
---
 drivers/gpu/drm/ttm/ttm_bo.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 95b86003c50d..e218a7ce490e 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -235,7 +235,7 @@ static void ttm_bo_delayed_delete(struct work_struct *work)
 
 	bo = container_of(work, typeof(*bo), delayed_delete);
 
-	dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP, false,
+	dma_resv_wait_timeout(&bo->base._resv, DMA_RESV_USAGE_BOOKKEEP, false,
 			      MAX_SCHEDULE_TIMEOUT);
 	dma_resv_lock(bo->base.resv, NULL);
 	ttm_bo_cleanup_memtype_use(bo);
@@ -270,7 +270,7 @@ static void ttm_bo_release(struct kref *kref)
 		drm_vma_offset_remove(bdev->vma_manager, &bo->base.vma_node);
 		ttm_mem_io_free(bdev, bo->resource);
 
-		if (!dma_resv_test_signaled(bo->base.resv,
+		if (!dma_resv_test_signaled(&bo->base._resv,
 					    DMA_RESV_USAGE_BOOKKEEP) ||
 		    (want_init_on_free() && (bo->ttm != NULL)) ||
 		    bo->type == ttm_bo_type_sg ||
-- 
2.51.0


From 41668e792e4606882b67f4febb59672fe68c4e9e Mon Sep 17 00:00:00 2001
From: Anusha Srivatsa <asrivats@redhat.com>
Date: Tue, 4 Mar 2025 16:05:31 -0500
Subject: [PATCH 04/16] drm/fsl-dcu: move to devm_platform_ioremap_resource()
 usage

Replace platform_get_resource + devm_ioremap_resource
with just devm_platform_ioremap_resource()

Used Coccinelle to do this change. SmPl patch:
@rule_1@
identifier res;
expression ioremap_res;
identifier pdev;
@@
-struct resource *res;
...
-res = platform_get_resource(pdev,...);
-ioremap_res = devm_ioremap_resource(...);
+ioremap_res = devm_platform_ioremap_resource(pdev,0);

Cc: Stefan Agner <stefan@agner.ch>
Cc: Alison Wang <alison.wang@nxp.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Anusha Srivatsa <asrivats@redhat.com>
Link: https://patchwork.freedesktop.org/patch/640851/?series=144073&rev=5
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index 03b076db9381..3bbfc1b56a65 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -260,7 +260,6 @@ static int fsl_dcu_drm_probe(struct platform_device *pdev)
 	struct fsl_dcu_drm_device *fsl_dev;
 	struct drm_device *drm;
 	struct device *dev = &pdev->dev;
-	struct resource *res;
 	void __iomem *base;
 	struct clk *pix_clk_in;
 	char pix_clk_name[32];
@@ -278,8 +277,7 @@ static int fsl_dcu_drm_probe(struct platform_device *pdev)
 		return -ENODEV;
 	fsl_dev->soc = id->data;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	base = devm_ioremap_resource(dev, res);
+	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base)) {
 		ret = PTR_ERR(base);
 		return ret;
-- 
2.51.0


From 9da894756ee1c67c020a80f4037a8a20652337c6 Mon Sep 17 00:00:00 2001
From: Anusha Srivatsa <asrivats@redhat.com>
Date: Tue, 4 Mar 2025 16:05:32 -0500
Subject: [PATCH 05/16] drm/hisilicon: move to devm_platform_ioremap_resource()
 usage

Replace platform_get_resource + devm_ioremap_resource
with just devm_platform_ioremap_resource()

Used Coccinelle to do this change. SmPl patch:
@rule_1@
identifier res;
expression ioremap_res;
identifier pdev;
@@
-struct resource *res;
...
-res = platform_get_resource(pdev,...);
-ioremap_res = devm_ioremap_resource(...);
+ioremap_res = devm_platform_ioremap_resource(pdev,0);

Cc: Xinliang Liu <xinliang.liu@linaro.org>
Cc: Tian Tao <tiantao6@hisilicon.com>
Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Yongqin Liu <yongqin.liu@linaro.org>
Cc: John Stultz <jstultz@google.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Anusha Srivatsa <asrivats@redhat.com>
Link: https://patchwork.freedesktop.org/patch/640850/?series=144073&rev=5
---
 drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c    | 4 +---
 drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c | 4 +---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
index 2eea9fb0e76b..e80debdc4176 100644
--- a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
+++ b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
@@ -825,7 +825,6 @@ static const struct component_ops dsi_ops = {
 static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi)
 {
 	struct dsi_hw_ctx *ctx = dsi->ctx;
-	struct resource *res;
 
 	ctx->pclk = devm_clk_get(&pdev->dev, "pclk");
 	if (IS_ERR(ctx->pclk)) {
@@ -833,8 +832,7 @@ static int dsi_parse_dt(struct platform_device *pdev, struct dw_dsi *dsi)
 		return PTR_ERR(ctx->pclk);
 	}
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	ctx->base = devm_ioremap_resource(&pdev->dev, res);
+	ctx->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(ctx->base)) {
 		DRM_ERROR("failed to remap dsi io region\n");
 		return PTR_ERR(ctx->base);
diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
index 2eb49177ac42..45c4eb008ad5 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
@@ -844,7 +844,6 @@ static struct drm_plane_funcs ade_plane_funcs = {
 static void *ade_hw_ctx_alloc(struct platform_device *pdev,
 			      struct drm_crtc *crtc)
 {
-	struct resource *res;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = pdev->dev.of_node;
 	struct ade_hw_ctx *ctx = NULL;
@@ -856,8 +855,7 @@ static void *ade_hw_ctx_alloc(struct platform_device *pdev,
 		return ERR_PTR(-ENOMEM);
 	}
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	ctx->base = devm_ioremap_resource(dev, res);
+	ctx->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(ctx->base)) {
 		DRM_ERROR("failed to remap ade io base\n");
 		return ERR_PTR(-EIO);
-- 
2.51.0


From 46babeac0e0856ca7d3c68a28328b55867922fe3 Mon Sep 17 00:00:00 2001
From: Anusha Srivatsa <asrivats@redhat.com>
Date: Tue, 4 Mar 2025 16:05:33 -0500
Subject: [PATCH 06/16] drm/mxsfb: move to devm_platform_ioremap_resource()
 usage

Replace platform_get_resource + devm_ioremap_resource
with just devm_platform_ioremap_resource()

Used Coccinelle to do this change. SmPl patch:
@rule_1@
identifier res;
expression ioremap_res;
identifier pdev;
@@
-struct resource *res;
...
-res = platform_get_resource(pdev,...);
-ioremap_res = devm_ioremap_resource(...);
+ioremap_res = devm_platform_ioremap_resource(pdev,0);

Cc: Marek Vasut <marex@denx.de>
Cc: Stefan Agner <stefan@agner.ch>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Anusha Srivatsa <asrivats@redhat.com>
Link: https://patchwork.freedesktop.org/patch/640852/?series=144073&rev=5
---
 drivers/gpu/drm/mxsfb/lcdif_drv.c | 4 +---
 drivers/gpu/drm/mxsfb/mxsfb_drv.c | 4 +---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/lcdif_drv.c b/drivers/gpu/drm/mxsfb/lcdif_drv.c
index 8ee00f59ca82..fcb2a7517377 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_drv.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_drv.c
@@ -134,7 +134,6 @@ static int lcdif_load(struct drm_device *drm)
 {
 	struct platform_device *pdev = to_platform_device(drm->dev);
 	struct lcdif_drm_private *lcdif;
-	struct resource *res;
 	int ret;
 
 	lcdif = devm_kzalloc(&pdev->dev, sizeof(*lcdif), GFP_KERNEL);
@@ -144,8 +143,7 @@ static int lcdif_load(struct drm_device *drm)
 	lcdif->drm = drm;
 	drm->dev_private = lcdif;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	lcdif->base = devm_ioremap_resource(drm->dev, res);
+	lcdif->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(lcdif->base))
 		return PTR_ERR(lcdif->base);
 
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
index 59020862cf65..377d4c4c9979 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
@@ -215,7 +215,6 @@ static int mxsfb_load(struct drm_device *drm,
 {
 	struct platform_device *pdev = to_platform_device(drm->dev);
 	struct mxsfb_drm_private *mxsfb;
-	struct resource *res;
 	int ret;
 
 	mxsfb = devm_kzalloc(&pdev->dev, sizeof(*mxsfb), GFP_KERNEL);
@@ -226,8 +225,7 @@ static int mxsfb_load(struct drm_device *drm,
 	drm->dev_private = mxsfb;
 	mxsfb->devdata = devdata;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mxsfb->base = devm_ioremap_resource(drm->dev, res);
+	mxsfb->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(mxsfb->base))
 		return PTR_ERR(mxsfb->base);
 
-- 
2.51.0


From fc51acfca9ca2049e0f6bde0ca41f760e081c281 Mon Sep 17 00:00:00 2001
From: Anusha Srivatsa <asrivats@redhat.com>
Date: Tue, 4 Mar 2025 16:05:36 -0500
Subject: [PATCH 07/16] drm/tegra: move to devm_platform_ioremap_resource()
 usage

Replace platform_get_resource + devm_ioremap_resource
with just devm_platform_ioremap_resource()

Used Coccinelle to do this change. SmPl patch:
@rule_1@
identifier res;
expression ioremap_res;
identifier pdev;
@@
-struct resource *res;
...
-res = platform_get_resource(pdev,...);
-ioremap_res = devm_ioremap_resource(...);
+ioremap_res = devm_platform_ioremap_resource(pdev,0);

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Mikko Perttunen <mperttunen@nvidia.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Anusha Srivatsa <asrivats@redhat.com>
Link: https://patchwork.freedesktop.org/patch/640855/?series=144073&rev=5
---
 drivers/gpu/drm/tegra/dsi.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/tegra/dsi.c b/drivers/gpu/drm/tegra/dsi.c
index 9bb077558167..b5089b772267 100644
--- a/drivers/gpu/drm/tegra/dsi.c
+++ b/drivers/gpu/drm/tegra/dsi.c
@@ -1564,7 +1564,6 @@ static int tegra_dsi_ganged_probe(struct tegra_dsi *dsi)
 static int tegra_dsi_probe(struct platform_device *pdev)
 {
 	struct tegra_dsi *dsi;
-	struct resource *regs;
 	int err;
 
 	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
@@ -1636,8 +1635,7 @@ static int tegra_dsi_probe(struct platform_device *pdev)
 		goto remove;
 	}
 
-	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	dsi->regs = devm_ioremap_resource(&pdev->dev, regs);
+	dsi->regs = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(dsi->regs)) {
 		err = PTR_ERR(dsi->regs);
 		goto remove;
-- 
2.51.0


From 5f7a654b5ed2828e0da8e8331f236854c70f0893 Mon Sep 17 00:00:00 2001
From: Charles Han <hanchunchao@inspur.com>
Date: Wed, 5 Mar 2025 18:30:42 +0800
Subject: [PATCH 08/16] drm/imx: legacy-bridge: fix inconsistent indenting
 warning

Fix below inconsistent indenting smatch warning.
smatch warnings:
drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c:79 devm_imx_drm_legacy_bridge() warn: inconsistent indenting

Signed-off-by: Charles Han <hanchunchao@inspur.com>
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250305103042.3017-1-hanchunchao@inspur.com
---
 drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c b/drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c
index 3ebf0b9866de..55a763045812 100644
--- a/drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c
+++ b/drivers/gpu/drm/bridge/imx/imx-legacy-bridge.c
@@ -76,9 +76,9 @@ struct drm_bridge *devm_imx_drm_legacy_bridge(struct device *dev,
 	imx_bridge->base.ops = DRM_BRIDGE_OP_MODES;
 	imx_bridge->base.type = type;
 
-       ret = devm_drm_bridge_add(dev, &imx_bridge->base);
-       if (ret)
-               return ERR_PTR(ret);
+	ret = devm_drm_bridge_add(dev, &imx_bridge->base);
+	if (ret)
+		return ERR_PTR(ret);
 
 	return &imx_bridge->base;
 }
-- 
2.51.0


From 9249a900fee4d7bdbe0dd183efbea09fbc8ce409 Mon Sep 17 00:00:00 2001
From: "Dr. David Alan Gilbert" <linux@treblig.org>
Date: Thu, 6 Mar 2025 15:51:55 +0000
Subject: [PATCH 09/16] drm/gma500: Remove unused mrst_clock_funcs

The mrst_clock_funcs const was added in 2013 by
commit ac6113ebb70d ("drm/gma500/mrst: Add SDVO clock calculation")
and commented as 'Not used yet'.

It's not been used since, so remove it.
The helper functions it points to are still used elsewhere.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250306155155.212599-1-linux@treblig.org
---
 drivers/gpu/drm/gma500/oaktrail_crtc.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/drivers/gpu/drm/gma500/oaktrail_crtc.c b/drivers/gpu/drm/gma500/oaktrail_crtc.c
index de8ccfe9890f..ea9b41af0867 100644
--- a/drivers/gpu/drm/gma500/oaktrail_crtc.c
+++ b/drivers/gpu/drm/gma500/oaktrail_crtc.c
@@ -658,10 +658,3 @@ const struct drm_crtc_helper_funcs oaktrail_helper_funcs = {
 	.prepare = gma_crtc_prepare,
 	.commit = gma_crtc_commit,
 };
-
-/* Not used yet */
-const struct gma_clock_funcs mrst_clock_funcs = {
-	.clock = mrst_lvds_clock,
-	.limit = mrst_limit,
-	.pll_is_valid = gma_pll_is_valid,
-};
-- 
2.51.0


From 2d4d775d11d314a505283cf31ae83460ef26ec70 Mon Sep 17 00:00:00 2001
From: Charles Han <hanchunchao@inspur.com>
Date: Wed, 5 Mar 2025 18:25:40 +0800
Subject: [PATCH 10/16] drm: pl111: fix inconsistent indenting warning

Fix below inconsistent indenting smatch warning.
smatch warnings:
drivers/gpu/drm/pl111/pl111_versatile.c:504 pl111_versatile_init() warn: inconsistent indenting

Signed-off-by: Charles Han <hanchunchao@inspur.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250305102540.2815-1-hanchunchao@inspur.com
---
 drivers/gpu/drm/pl111/pl111_versatile.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/pl111/pl111_versatile.c b/drivers/gpu/drm/pl111/pl111_versatile.c
index 1e4b28d03f4d..5f460b296c0c 100644
--- a/drivers/gpu/drm/pl111/pl111_versatile.c
+++ b/drivers/gpu/drm/pl111/pl111_versatile.c
@@ -501,7 +501,7 @@ int pl111_versatile_init(struct device *dev, struct pl111_drm_dev_private *priv)
 	 * if we find it, it will take precedence. This is on the Integrator/AP
 	 * which only has this option for PL110 graphics.
 	 */
-	 if (versatile_clcd_type == INTEGRATOR_CLCD_CM) {
+	if (versatile_clcd_type == INTEGRATOR_CLCD_CM) {
 		np = of_find_matching_node_and_match(NULL, impd1_clcd_of_match,
 						     &clcd_id);
 		if (np)
-- 
2.51.0


From 6fdbc11502b2fd47206b833ded2e407c84b6658c Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:01 +0100
Subject: [PATCH 11/16] drm/vkms: Extract vkms_connector header
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Up until now, the logic to manage connectors was in vkms_output.c.

Since more options will be added to connectors in the future, extract
the code to its own file.

Refactor, no functional changes.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-2-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/Makefile         |  3 +-
 drivers/gpu/drm/vkms/vkms_connector.c | 50 +++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_connector.h | 17 +++++++++
 drivers/gpu/drm/vkms/vkms_output.c    | 41 +++-------------------
 4 files changed, 73 insertions(+), 38 deletions(-)
 create mode 100644 drivers/gpu/drm/vkms/vkms_connector.c
 create mode 100644 drivers/gpu/drm/vkms/vkms_connector.h

diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile
index 1b28a6a32948..6b0615c424f2 100644
--- a/drivers/gpu/drm/vkms/Makefile
+++ b/drivers/gpu/drm/vkms/Makefile
@@ -6,6 +6,7 @@ vkms-y := \
 	vkms_formats.o \
 	vkms_crtc.o \
 	vkms_composer.o \
-	vkms_writeback.o
+	vkms_writeback.o \
+	vkms_connector.o
 
 obj-$(CONFIG_DRM_VKMS) += vkms.o
diff --git a/drivers/gpu/drm/vkms/vkms_connector.c b/drivers/gpu/drm/vkms/vkms_connector.c
new file mode 100644
index 000000000000..fc97f265dea6
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_connector.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_probe_helper.h>
+
+#include "vkms_connector.h"
+
+static const struct drm_connector_funcs vkms_connector_funcs = {
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int vkms_conn_get_modes(struct drm_connector *connector)
+{
+	int count;
+
+	/* Use the default modes list from DRM */
+	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
+	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
+
+	return count;
+}
+
+static const struct drm_connector_helper_funcs vkms_conn_helper_funcs = {
+	.get_modes    = vkms_conn_get_modes,
+};
+
+struct drm_connector *vkms_connector_init(struct vkms_device *vkmsdev)
+{
+	struct drm_device *dev = &vkmsdev->drm;
+	struct drm_connector *connector;
+	int ret;
+
+	connector = drmm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
+	if (!connector)
+		return ERR_PTR(-ENOMEM);
+
+	ret = drmm_connector_init(dev, connector, &vkms_connector_funcs,
+				  DRM_MODE_CONNECTOR_VIRTUAL, NULL);
+	if (ret)
+		return ERR_PTR(ret);
+
+	drm_connector_helper_add(connector, &vkms_conn_helper_funcs);
+
+	return connector;
+}
diff --git a/drivers/gpu/drm/vkms/vkms_connector.h b/drivers/gpu/drm/vkms/vkms_connector.h
new file mode 100644
index 000000000000..beb5ebe09155
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_connector.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _VKMS_CONNECTOR_H_
+#define _VKMS_CONNECTOR_H_
+
+#include "vkms_drv.h"
+
+/**
+ * vkms_connector_init() - Initialize a connector
+ * @vkmsdev: VKMS device containing the connector
+ *
+ * Returns:
+ * The connector or an error on failure.
+ */
+struct drm_connector *vkms_connector_init(struct vkms_device *vkmsdev);
+
+#endif /* _VKMS_CONNECTOR_H_ */
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index 22f0d678af3a..b01c3e9289d0 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -1,32 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0+
 
+#include "vkms_connector.h"
 #include "vkms_drv.h"
-#include <drm/drm_atomic_helper.h>
-#include <drm/drm_edid.h>
 #include <drm/drm_managed.h>
-#include <drm/drm_probe_helper.h>
-
-static const struct drm_connector_funcs vkms_connector_funcs = {
-	.fill_modes = drm_helper_probe_single_connector_modes,
-	.reset = drm_atomic_helper_connector_reset,
-	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
-	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
-};
-
-static int vkms_conn_get_modes(struct drm_connector *connector)
-{
-	int count;
-
-	/* Use the default modes list from DRM */
-	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
-	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
-
-	return count;
-}
-
-static const struct drm_connector_helper_funcs vkms_conn_helper_funcs = {
-	.get_modes    = vkms_conn_get_modes,
-};
 
 int vkms_output_init(struct vkms_device *vkmsdev)
 {
@@ -73,21 +49,12 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 		}
 	}
 
-	connector = drmm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
-	if (!connector) {
-		DRM_ERROR("Failed to allocate connector\n");
-		return -ENOMEM;
-	}
-
-	ret = drmm_connector_init(dev, connector, &vkms_connector_funcs,
-				  DRM_MODE_CONNECTOR_VIRTUAL, NULL);
-	if (ret) {
+	connector = vkms_connector_init(vkmsdev);
+	if (IS_ERR(connector)) {
 		DRM_ERROR("Failed to init connector\n");
-		return ret;
+		return PTR_ERR(connector);
 	}
 
-	drm_connector_helper_add(connector, &vkms_conn_helper_funcs);
-
 	encoder = drmm_kzalloc(dev, sizeof(*encoder), GFP_KERNEL);
 	if (!encoder) {
 		DRM_ERROR("Failed to allocate encoder\n");
-- 
2.51.0


From a833c5880a5fbecd71f60efca6ad641e51d0d29e Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:02 +0100
Subject: [PATCH 12/16] drm/vkms: Create vkms_connector struct
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Create a structure wrapping the drm_connector.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-3-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/vkms_connector.c |  8 ++++----
 drivers/gpu/drm/vkms/vkms_connector.h | 11 ++++++++++-
 drivers/gpu/drm/vkms/vkms_output.c    |  4 ++--
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_connector.c b/drivers/gpu/drm/vkms/vkms_connector.c
index fc97f265dea6..ab8b52a84151 100644
--- a/drivers/gpu/drm/vkms/vkms_connector.c
+++ b/drivers/gpu/drm/vkms/vkms_connector.c
@@ -29,22 +29,22 @@ static const struct drm_connector_helper_funcs vkms_conn_helper_funcs = {
 	.get_modes    = vkms_conn_get_modes,
 };
 
-struct drm_connector *vkms_connector_init(struct vkms_device *vkmsdev)
+struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev)
 {
 	struct drm_device *dev = &vkmsdev->drm;
-	struct drm_connector *connector;
+	struct vkms_connector *connector;
 	int ret;
 
 	connector = drmm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 	if (!connector)
 		return ERR_PTR(-ENOMEM);
 
-	ret = drmm_connector_init(dev, connector, &vkms_connector_funcs,
+	ret = drmm_connector_init(dev, &connector->base, &vkms_connector_funcs,
 				  DRM_MODE_CONNECTOR_VIRTUAL, NULL);
 	if (ret)
 		return ERR_PTR(ret);
 
-	drm_connector_helper_add(connector, &vkms_conn_helper_funcs);
+	drm_connector_helper_add(&connector->base, &vkms_conn_helper_funcs);
 
 	return connector;
 }
diff --git a/drivers/gpu/drm/vkms/vkms_connector.h b/drivers/gpu/drm/vkms/vkms_connector.h
index beb5ebe09155..c9149c1b7af0 100644
--- a/drivers/gpu/drm/vkms/vkms_connector.h
+++ b/drivers/gpu/drm/vkms/vkms_connector.h
@@ -5,6 +5,15 @@
 
 #include "vkms_drv.h"
 
+/**
+ * struct vkms_connector - VKMS custom type wrapping around the DRM connector
+ *
+ * @drm: Base DRM connector
+ */
+struct vkms_connector {
+	struct drm_connector base;
+};
+
 /**
  * vkms_connector_init() - Initialize a connector
  * @vkmsdev: VKMS device containing the connector
@@ -12,6 +21,6 @@
  * Returns:
  * The connector or an error on failure.
  */
-struct drm_connector *vkms_connector_init(struct vkms_device *vkmsdev);
+struct vkms_connector *vkms_connector_init(struct vkms_device *vkmsdev);
 
 #endif /* _VKMS_CONNECTOR_H_ */
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index b01c3e9289d0..4b5abe159add 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -7,7 +7,7 @@
 int vkms_output_init(struct vkms_device *vkmsdev)
 {
 	struct drm_device *dev = &vkmsdev->drm;
-	struct drm_connector *connector;
+	struct vkms_connector *connector;
 	struct drm_encoder *encoder;
 	struct vkms_output *output;
 	struct vkms_plane *primary, *overlay, *cursor = NULL;
@@ -69,7 +69,7 @@ int vkms_output_init(struct vkms_device *vkmsdev)
 	encoder->possible_crtcs = drm_crtc_mask(&output->crtc);
 
 	/* Attach the encoder and the connector */
-	ret = drm_connector_attach_encoder(connector, encoder);
+	ret = drm_connector_attach_encoder(&connector->base, encoder);
 	if (ret) {
 		DRM_ERROR("Failed to attach connector to encoder\n");
 		return ret;
-- 
2.51.0


From 5b5a56d9a2d64e8395dfbaddecb3e5149d7ecae8 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:03 +0100
Subject: [PATCH 13/16] drm/vkms: Add KUnit test scaffolding
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Add the required boilerplate to start creating KUnit test.

To run the tests:

    $ ./tools/testing/kunit/kunit.py run \
      --kunitconfig=drivers/gpu/drm/vkms/tests

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Co-developed-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
Co-developed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-4-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/Kconfig                  | 15 +++++++++++++++
 drivers/gpu/drm/vkms/Makefile                 |  1 +
 drivers/gpu/drm/vkms/tests/.kunitconfig       |  4 ++++
 drivers/gpu/drm/vkms/tests/Makefile           |  3 +++
 drivers/gpu/drm/vkms/tests/vkms_config_test.c | 19 +++++++++++++++++++
 5 files changed, 42 insertions(+)
 create mode 100644 drivers/gpu/drm/vkms/tests/.kunitconfig
 create mode 100644 drivers/gpu/drm/vkms/tests/Makefile
 create mode 100644 drivers/gpu/drm/vkms/tests/vkms_config_test.c

diff --git a/drivers/gpu/drm/vkms/Kconfig b/drivers/gpu/drm/vkms/Kconfig
index 9def079f685b..3c02f928ffe6 100644
--- a/drivers/gpu/drm/vkms/Kconfig
+++ b/drivers/gpu/drm/vkms/Kconfig
@@ -14,3 +14,18 @@ config DRM_VKMS
 	  a VKMS.
 
 	  If M is selected the module will be called vkms.
+
+config DRM_VKMS_KUNIT_TEST
+	tristate "KUnit tests for VKMS" if !KUNIT_ALL_TESTS
+	depends on DRM_VKMS && KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  This builds unit tests for VKMS. This option is not useful for
+	  distributions or general kernels, but only for kernel
+	  developers working on VKMS.
+
+	  For more information on KUnit and unit tests in general,
+	  please refer to the KUnit documentation in
+	  Documentation/dev-tools/kunit/.
+
+	  If in doubt, say "N".
diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile
index 6b0615c424f2..c23eee2f3df4 100644
--- a/drivers/gpu/drm/vkms/Makefile
+++ b/drivers/gpu/drm/vkms/Makefile
@@ -10,3 +10,4 @@ vkms-y := \
 	vkms_connector.o
 
 obj-$(CONFIG_DRM_VKMS) += vkms.o
+obj-$(CONFIG_DRM_VKMS_KUNIT_TEST) += tests/
diff --git a/drivers/gpu/drm/vkms/tests/.kunitconfig b/drivers/gpu/drm/vkms/tests/.kunitconfig
new file mode 100644
index 000000000000..6a2d87068edc
--- /dev/null
+++ b/drivers/gpu/drm/vkms/tests/.kunitconfig
@@ -0,0 +1,4 @@
+CONFIG_KUNIT=y
+CONFIG_DRM=y
+CONFIG_DRM_VKMS=y
+CONFIG_DRM_VKMS_KUNIT_TEST=y
diff --git a/drivers/gpu/drm/vkms/tests/Makefile b/drivers/gpu/drm/vkms/tests/Makefile
new file mode 100644
index 000000000000..9ded37b67a46
--- /dev/null
+++ b/drivers/gpu/drm/vkms/tests/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_DRM_VKMS_KUNIT_TEST) += vkms_config_test.o
diff --git a/drivers/gpu/drm/vkms/tests/vkms_config_test.c b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
new file mode 100644
index 000000000000..1177e62e19cb
--- /dev/null
+++ b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <kunit/test.h>
+
+MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
+
+static struct kunit_case vkms_config_test_cases[] = {
+	{}
+};
+
+static struct kunit_suite vkms_config_test_suite = {
+	.name = "vkms-config",
+	.test_cases = vkms_config_test_cases,
+};
+
+kunit_test_suite(vkms_config_test_suite);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Kunit test for vkms config utility");
-- 
2.51.0


From d3ae1e394bdc267a1699f7ac2ff3d3a990e791b9 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:04 +0100
Subject: [PATCH 14/16] drm/vkms: Extract vkms_config header
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Creating a new vkms_config structure will be more complex once we
start adding more options.

Extract the vkms_config structure to its own header and source files
and add functions to create and delete a vkms_config and to initialize
debugfs.

Refactor, no functional changes.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Co-developed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-5-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/Makefile                 |  3 +-
 drivers/gpu/drm/vkms/tests/vkms_config_test.c | 13 +++++
 drivers/gpu/drm/vkms/vkms_config.c            | 50 +++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_config.h            | 47 +++++++++++++++++
 drivers/gpu/drm/vkms/vkms_drv.c               | 34 +++----------
 drivers/gpu/drm/vkms/vkms_drv.h               | 15 +-----
 drivers/gpu/drm/vkms/vkms_output.c            |  1 +
 7 files changed, 121 insertions(+), 42 deletions(-)
 create mode 100644 drivers/gpu/drm/vkms/vkms_config.c
 create mode 100644 drivers/gpu/drm/vkms/vkms_config.h

diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile
index c23eee2f3df4..d657865e573f 100644
--- a/drivers/gpu/drm/vkms/Makefile
+++ b/drivers/gpu/drm/vkms/Makefile
@@ -7,7 +7,8 @@ vkms-y := \
 	vkms_crtc.o \
 	vkms_composer.o \
 	vkms_writeback.o \
-	vkms_connector.o
+	vkms_connector.o \
+	vkms_config.o
 
 obj-$(CONFIG_DRM_VKMS) += vkms.o
 obj-$(CONFIG_DRM_VKMS_KUNIT_TEST) += tests/
diff --git a/drivers/gpu/drm/vkms/tests/vkms_config_test.c b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
index 1177e62e19cb..a7060504f3dc 100644
--- a/drivers/gpu/drm/vkms/tests/vkms_config_test.c
+++ b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
@@ -2,9 +2,22 @@
 
 #include <kunit/test.h>
 
+#include "../vkms_config.h"
+
 MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
 
+static void vkms_config_test_empty_config(struct kunit *test)
+{
+	struct vkms_config *config;
+
+	config = vkms_config_create();
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, config);
+
+	vkms_config_destroy(config);
+}
+
 static struct kunit_case vkms_config_test_cases[] = {
+	KUNIT_CASE(vkms_config_test_empty_config),
 	{}
 };
 
diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
new file mode 100644
index 000000000000..42caa421876e
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/slab.h>
+
+#include <drm/drm_print.h>
+#include <drm/drm_debugfs.h>
+#include <kunit/visibility.h>
+
+#include "vkms_config.h"
+
+struct vkms_config *vkms_config_create(void)
+{
+	struct vkms_config *config;
+
+	config = kzalloc(sizeof(*config), GFP_KERNEL);
+	if (!config)
+		return ERR_PTR(-ENOMEM);
+
+	return config;
+}
+EXPORT_SYMBOL_IF_KUNIT(vkms_config_create);
+
+void vkms_config_destroy(struct vkms_config *config)
+{
+	kfree(config);
+}
+EXPORT_SYMBOL_IF_KUNIT(vkms_config_destroy);
+
+static int vkms_config_show(struct seq_file *m, void *data)
+{
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *dev = entry->dev;
+	struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
+
+	seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
+	seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
+	seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
+
+	return 0;
+}
+
+static const struct drm_debugfs_info vkms_config_debugfs_list[] = {
+	{ "vkms_config", vkms_config_show, 0 },
+};
+
+void vkms_config_register_debugfs(struct vkms_device *vkms_device)
+{
+	drm_debugfs_add_files(&vkms_device->drm, vkms_config_debugfs_list,
+			      ARRAY_SIZE(vkms_config_debugfs_list));
+}
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
new file mode 100644
index 000000000000..ced10f56a812
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _VKMS_CONFIG_H_
+#define _VKMS_CONFIG_H_
+
+#include <linux/types.h>
+
+#include "vkms_drv.h"
+
+/**
+ * struct vkms_config - General configuration for VKMS driver
+ *
+ * @writeback: If true, a writeback buffer can be attached to the CRTC
+ * @cursor: If true, a cursor plane is created in the VKMS device
+ * @overlay: If true, NUM_OVERLAY_PLANES will be created for the VKMS device
+ * @dev: Used to store the current VKMS device. Only set when the device is instantiated.
+ */
+struct vkms_config {
+	bool writeback;
+	bool cursor;
+	bool overlay;
+	struct vkms_device *dev;
+};
+
+/**
+ * vkms_config_create() - Create a new VKMS configuration
+ *
+ * Returns:
+ * The new vkms_config or an error. Call vkms_config_destroy() to free the
+ * returned configuration.
+ */
+struct vkms_config *vkms_config_create(void);
+
+/**
+ * vkms_config_destroy() - Free a VKMS configuration
+ * @config: vkms_config to free
+ */
+void vkms_config_destroy(struct vkms_config *config);
+
+/**
+ * vkms_config_register_debugfs() - Register a debugfs file to show the device's
+ * configuration
+ * @vkms_device: Device to register
+ */
+void vkms_config_register_debugfs(struct vkms_device *vkms_device);
+
+#endif /* _VKMS_CONFIG_H_ */
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index b6de91134a22..37de0658e6ee 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -27,11 +27,9 @@
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_vblank.h>
 
+#include "vkms_config.h"
 #include "vkms_drv.h"
 
-#include <drm/drm_print.h>
-#include <drm/drm_debugfs.h>
-
 #define DRIVER_NAME	"vkms"
 #define DRIVER_DESC	"Virtual Kernel Mode Setting"
 #define DRIVER_MAJOR	1
@@ -81,23 +79,6 @@ static void vkms_atomic_commit_tail(struct drm_atomic_state *old_state)
 	drm_atomic_helper_cleanup_planes(dev, old_state);
 }
 
-static int vkms_config_show(struct seq_file *m, void *data)
-{
-	struct drm_debugfs_entry *entry = m->private;
-	struct drm_device *dev = entry->dev;
-	struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
-
-	seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
-	seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
-	seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
-
-	return 0;
-}
-
-static const struct drm_debugfs_info vkms_config_debugfs_list[] = {
-	{ "vkms_config", vkms_config_show, 0 },
-};
-
 static const struct drm_driver vkms_driver = {
 	.driver_features	= DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
 	.fops			= &vkms_driver_fops,
@@ -208,8 +189,7 @@ static int vkms_create(struct vkms_config *config)
 	if (ret)
 		goto out_devres;
 
-	drm_debugfs_add_files(&vkms_device->drm, vkms_config_debugfs_list,
-			      ARRAY_SIZE(vkms_config_debugfs_list));
+	vkms_config_register_debugfs(vkms_device);
 
 	ret = drm_dev_register(&vkms_device->drm, 0);
 	if (ret)
@@ -231,9 +211,9 @@ static int __init vkms_init(void)
 	int ret;
 	struct vkms_config *config;
 
-	config = kmalloc(sizeof(*config), GFP_KERNEL);
-	if (!config)
-		return -ENOMEM;
+	config = vkms_config_create();
+	if (IS_ERR(config))
+		return PTR_ERR(config);
 
 	config->cursor = enable_cursor;
 	config->writeback = enable_writeback;
@@ -241,7 +221,7 @@ static int __init vkms_init(void)
 
 	ret = vkms_create(config);
 	if (ret) {
-		kfree(config);
+		vkms_config_destroy(config);
 		return ret;
 	}
 
@@ -275,7 +255,7 @@ static void __exit vkms_exit(void)
 		return;
 
 	vkms_destroy(default_config);
-	kfree(default_config);
+	vkms_config_destroy(default_config);
 }
 
 module_init(vkms_init);
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index abbb652be2b5..af7081c940d6 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -189,20 +189,7 @@ struct vkms_output {
 	spinlock_t composer_lock;
 };
 
-/**
- * struct vkms_config - General configuration for VKMS driver
- *
- * @writeback: If true, a writeback buffer can be attached to the CRTC
- * @cursor: If true, a cursor plane is created in the VKMS device
- * @overlay: If true, NUM_OVERLAY_PLANES will be created for the VKMS device
- * @dev: Used to store the current VKMS device. Only set when the device is instantiated.
- */
-struct vkms_config {
-	bool writeback;
-	bool cursor;
-	bool overlay;
-	struct vkms_device *dev;
-};
+struct vkms_config;
 
 /**
  * struct vkms_device - Description of a VKMS device
diff --git a/drivers/gpu/drm/vkms/vkms_output.c b/drivers/gpu/drm/vkms/vkms_output.c
index 4b5abe159add..068a7f87ecec 100644
--- a/drivers/gpu/drm/vkms/vkms_output.c
+++ b/drivers/gpu/drm/vkms/vkms_output.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 
+#include "vkms_config.h"
 #include "vkms_connector.h"
 #include "vkms_drv.h"
 #include <drm/drm_managed.h>
-- 
2.51.0


From 8b059b0c3f721373f45c9d72d0481345e765be86 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:05 +0100
Subject: [PATCH 15/16] drm/vkms: Move default_config creation to its own
 function
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Extract the initialization of the default configuration to a function.
Refactor, no functional changes.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Co-developed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-6-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/tests/vkms_config_test.c | 38 +++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_config.c            | 18 +++++++++
 drivers/gpu/drm/vkms/vkms_config.h            | 14 +++++++
 drivers/gpu/drm/vkms/vkms_drv.c               |  6 +--
 4 files changed, 71 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/vkms/tests/vkms_config_test.c b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
index a7060504f3dc..d8644a1e3e18 100644
--- a/drivers/gpu/drm/vkms/tests/vkms_config_test.c
+++ b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
@@ -6,6 +6,12 @@
 
 MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
 
+struct default_config_case {
+	bool enable_cursor;
+	bool enable_writeback;
+	bool enable_overlay;
+};
+
 static void vkms_config_test_empty_config(struct kunit *test)
 {
 	struct vkms_config *config;
@@ -16,8 +22,40 @@ static void vkms_config_test_empty_config(struct kunit *test)
 	vkms_config_destroy(config);
 }
 
+static struct default_config_case default_config_cases[] = {
+	{ false, false, false },
+	{ true, false, false },
+	{ true, true, false },
+	{ true, false, true },
+	{ false, true, false },
+	{ false, true, true },
+	{ false, false, true },
+	{ true, true, true },
+};
+
+KUNIT_ARRAY_PARAM(default_config, default_config_cases, NULL);
+
+static void vkms_config_test_default_config(struct kunit *test)
+{
+	const struct default_config_case *params = test->param_value;
+	struct vkms_config *config;
+
+	config = vkms_config_default_create(params->enable_cursor,
+					    params->enable_writeback,
+					    params->enable_overlay);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, config);
+
+	KUNIT_EXPECT_EQ(test, config->cursor, params->enable_cursor);
+	KUNIT_EXPECT_EQ(test, config->writeback, params->enable_writeback);
+	KUNIT_EXPECT_EQ(test, config->overlay, params->enable_overlay);
+
+	vkms_config_destroy(config);
+}
+
 static struct kunit_case vkms_config_test_cases[] = {
 	KUNIT_CASE(vkms_config_test_empty_config),
+	KUNIT_CASE_PARAM(vkms_config_test_default_config,
+			 default_config_gen_params),
 	{}
 };
 
diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index 42caa421876e..0af8e6dc0a01 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -20,6 +20,24 @@ struct vkms_config *vkms_config_create(void)
 }
 EXPORT_SYMBOL_IF_KUNIT(vkms_config_create);
 
+struct vkms_config *vkms_config_default_create(bool enable_cursor,
+					       bool enable_writeback,
+					       bool enable_overlay)
+{
+	struct vkms_config *config;
+
+	config = vkms_config_create();
+	if (IS_ERR(config))
+		return config;
+
+	config->cursor = enable_cursor;
+	config->writeback = enable_writeback;
+	config->overlay = enable_overlay;
+
+	return config;
+}
+EXPORT_SYMBOL_IF_KUNIT(vkms_config_default_create);
+
 void vkms_config_destroy(struct vkms_config *config)
 {
 	kfree(config);
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index ced10f56a812..d0868750826a 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -31,6 +31,20 @@ struct vkms_config {
  */
 struct vkms_config *vkms_config_create(void);
 
+/**
+ * vkms_config_default_create() - Create the configuration for the default device
+ * @enable_cursor: Create or not a cursor plane
+ * @enable_writeback: Create or not a writeback connector
+ * @enable_overlay: Create or not overlay planes
+ *
+ * Returns:
+ * The default vkms_config or an error. Call vkms_config_destroy() to free the
+ * returned configuration.
+ */
+struct vkms_config *vkms_config_default_create(bool enable_cursor,
+					       bool enable_writeback,
+					       bool enable_overlay);
+
 /**
  * vkms_config_destroy() - Free a VKMS configuration
  * @config: vkms_config to free
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index 37de0658e6ee..582d5825f42b 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -211,14 +211,10 @@ static int __init vkms_init(void)
 	int ret;
 	struct vkms_config *config;
 
-	config = vkms_config_create();
+	config = vkms_config_default_create(enable_cursor, enable_writeback, enable_overlay);
 	if (IS_ERR(config))
 		return PTR_ERR(config);
 
-	config->cursor = enable_cursor;
-	config->writeback = enable_writeback;
-	config->overlay = enable_overlay;
-
 	ret = vkms_create(config);
 	if (ret) {
 		vkms_config_destroy(config);
-- 
2.51.0


From 969a3a4e2ba30138f065dbf8904798a80a528ca5 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Tue, 18 Feb 2025 11:12:06 +0100
Subject: [PATCH 16/16] drm/vkms: Set device name from vkms_config
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

In order to be able to create multiple devices, the device name needs to
be unique.

Allow to set it in the VKMS configuration.

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250218101214.5790-7-jose.exposito89@gmail.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/vkms/tests/vkms_config_test.c |  7 ++++++-
 drivers/gpu/drm/vkms/vkms_config.c            | 14 ++++++++++++--
 drivers/gpu/drm/vkms/vkms_config.h            | 18 +++++++++++++++++-
 drivers/gpu/drm/vkms/vkms_drv.c               |  4 +++-
 drivers/gpu/drm/vkms/vkms_drv.h               |  2 ++
 5 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/vkms/tests/vkms_config_test.c b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
index d8644a1e3e18..92798590051b 100644
--- a/drivers/gpu/drm/vkms/tests/vkms_config_test.c
+++ b/drivers/gpu/drm/vkms/tests/vkms_config_test.c
@@ -15,10 +15,15 @@ struct default_config_case {
 static void vkms_config_test_empty_config(struct kunit *test)
 {
 	struct vkms_config *config;
+	const char *dev_name = "test";
 
-	config = vkms_config_create();
+	config = vkms_config_create(dev_name);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, config);
 
+	/* The dev_name string and the config have different lifetimes */
+	dev_name = NULL;
+	KUNIT_EXPECT_STREQ(test, vkms_config_get_device_name(config), "test");
+
 	vkms_config_destroy(config);
 }
 
diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
index 0af8e6dc0a01..9fb08d94a351 100644
--- a/drivers/gpu/drm/vkms/vkms_config.c
+++ b/drivers/gpu/drm/vkms/vkms_config.c
@@ -8,7 +8,7 @@
 
 #include "vkms_config.h"
 
-struct vkms_config *vkms_config_create(void)
+struct vkms_config *vkms_config_create(const char *dev_name)
 {
 	struct vkms_config *config;
 
@@ -16,6 +16,12 @@ struct vkms_config *vkms_config_create(void)
 	if (!config)
 		return ERR_PTR(-ENOMEM);
 
+	config->dev_name = kstrdup_const(dev_name, GFP_KERNEL);
+	if (!config->dev_name) {
+		kfree(config);
+		return ERR_PTR(-ENOMEM);
+	}
+
 	return config;
 }
 EXPORT_SYMBOL_IF_KUNIT(vkms_config_create);
@@ -26,7 +32,7 @@ struct vkms_config *vkms_config_default_create(bool enable_cursor,
 {
 	struct vkms_config *config;
 
-	config = vkms_config_create();
+	config = vkms_config_create(DEFAULT_DEVICE_NAME);
 	if (IS_ERR(config))
 		return config;
 
@@ -40,6 +46,7 @@ EXPORT_SYMBOL_IF_KUNIT(vkms_config_default_create);
 
 void vkms_config_destroy(struct vkms_config *config)
 {
+	kfree_const(config->dev_name);
 	kfree(config);
 }
 EXPORT_SYMBOL_IF_KUNIT(vkms_config_destroy);
@@ -49,7 +56,10 @@ static int vkms_config_show(struct seq_file *m, void *data)
 	struct drm_debugfs_entry *entry = m->private;
 	struct drm_device *dev = entry->dev;
 	struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev);
+	const char *dev_name;
 
+	dev_name = vkms_config_get_device_name((struct vkms_config *)vkmsdev->config);
+	seq_printf(m, "dev_name=%s\n", dev_name);
 	seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback);
 	seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor);
 	seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay);
diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
index d0868750826a..fcaa909fb2e0 100644
--- a/drivers/gpu/drm/vkms/vkms_config.h
+++ b/drivers/gpu/drm/vkms/vkms_config.h
@@ -10,12 +10,14 @@
 /**
  * struct vkms_config - General configuration for VKMS driver
  *
+ * @dev_name: Name of the device
  * @writeback: If true, a writeback buffer can be attached to the CRTC
  * @cursor: If true, a cursor plane is created in the VKMS device
  * @overlay: If true, NUM_OVERLAY_PLANES will be created for the VKMS device
  * @dev: Used to store the current VKMS device. Only set when the device is instantiated.
  */
 struct vkms_config {
+	const char *dev_name;
 	bool writeback;
 	bool cursor;
 	bool overlay;
@@ -24,12 +26,13 @@ struct vkms_config {
 
 /**
  * vkms_config_create() - Create a new VKMS configuration
+ * @dev_name: Name of the device
  *
  * Returns:
  * The new vkms_config or an error. Call vkms_config_destroy() to free the
  * returned configuration.
  */
-struct vkms_config *vkms_config_create(void);
+struct vkms_config *vkms_config_create(const char *dev_name);
 
 /**
  * vkms_config_default_create() - Create the configuration for the default device
@@ -51,6 +54,19 @@ struct vkms_config *vkms_config_default_create(bool enable_cursor,
  */
 void vkms_config_destroy(struct vkms_config *config);
 
+/**
+ * vkms_config_get_device_name() - Return the name of the device
+ * @config: Configuration to get the device name from
+ *
+ * Returns:
+ * The device name. Only valid while @config is valid.
+ */
+static inline const char *
+vkms_config_get_device_name(struct vkms_config *config)
+{
+	return config->dev_name;
+}
+
 /**
  * vkms_config_register_debugfs() - Register a debugfs file to show the device's
  * configuration
diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index 582d5825f42b..ba977ef09b2b 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -151,8 +151,10 @@ static int vkms_create(struct vkms_config *config)
 	int ret;
 	struct platform_device *pdev;
 	struct vkms_device *vkms_device;
+	const char *dev_name;
 
-	pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
+	dev_name = vkms_config_get_device_name(config);
+	pdev = platform_device_register_simple(dev_name, -1, NULL, 0);
 	if (IS_ERR(pdev))
 		return PTR_ERR(pdev);
 
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index af7081c940d6..a74a7fc3a056 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -12,6 +12,8 @@
 #include <drm/drm_encoder.h>
 #include <drm/drm_writeback.h>
 
+#define DEFAULT_DEVICE_NAME "vkms"
+
 #define XRES_MIN    10
 #define YRES_MIN    10
 
-- 
2.51.0