[PATCH 1/4] drm/client: Add client free callback to unprepare fb_helper
Patrik Jakobsson
patrik.r.jakobsson at gmail.com
Tue Oct 21 06:54:11 PDT 2025
On Thu, Oct 9, 2025 at 3:31 PM Thomas Zimmermann <tzimmermann at suse.de> wrote:
>
> Add free callback to struct drm_client_funcs. Invoke function to
> free the client memory as part of the release process. Implement
> free for fbdev emulation.
>
> Fbdev emulation allocates and prepares client memory in
> drm_fbdev_client_setup(). The release happens in fb_destroy from
> struct fb_ops. Multiple implementations of this callback exist in
> the various drivers that provide fbdev implementation. Each of them
> needs to follow the implementation details of the fbdev setup code.
>
> Adding a free callback for the client puts the unprepare and release
> of the fbdev client in a single place.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
For gma500:
Acked-by: Patrik Jakobsson <patrik.r.jakobsson at gmail.com>
> ---
> drivers/gpu/drm/armada/armada_fbdev.c | 2 --
> drivers/gpu/drm/clients/drm_fbdev_client.c | 17 +++++++++++++++--
> drivers/gpu/drm/drm_client.c | 4 ++++
> drivers/gpu/drm/drm_fbdev_dma.c | 4 ----
> drivers/gpu/drm/drm_fbdev_shmem.c | 2 --
> drivers/gpu/drm/drm_fbdev_ttm.c | 2 --
> drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 2 --
> drivers/gpu/drm/gma500/fbdev.c | 3 ---
> drivers/gpu/drm/i915/display/intel_fbdev.c | 2 --
> drivers/gpu/drm/msm/msm_fbdev.c | 2 --
> drivers/gpu/drm/omapdrm/omap_fbdev.c | 2 --
> drivers/gpu/drm/radeon/radeon_fbdev.c | 2 --
> drivers/gpu/drm/tegra/fbdev.c | 2 --
> include/drm/drm_client.h | 10 ++++++++++
> 14 files changed, 29 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/gpu/drm/armada/armada_fbdev.c b/drivers/gpu/drm/armada/armada_fbdev.c
> index cb53cc91bafb..22e2081bfa04 100644
> --- a/drivers/gpu/drm/armada/armada_fbdev.c
> +++ b/drivers/gpu/drm/armada/armada_fbdev.c
> @@ -28,8 +28,6 @@ static void armada_fbdev_fb_destroy(struct fb_info *info)
> fbh->fb->funcs->destroy(fbh->fb);
>
> drm_client_release(&fbh->client);
> - drm_fb_helper_unprepare(fbh);
> - kfree(fbh);
> }
>
> static const struct fb_ops armada_fb_ops = {
> diff --git a/drivers/gpu/drm/clients/drm_fbdev_client.c b/drivers/gpu/drm/clients/drm_fbdev_client.c
> index f894ba52bdb5..5336accab1b6 100644
> --- a/drivers/gpu/drm/clients/drm_fbdev_client.c
> +++ b/drivers/gpu/drm/clients/drm_fbdev_client.c
> @@ -13,16 +13,28 @@
> * struct drm_client_funcs
> */
>
> +static void drm_fbdev_client_free(struct drm_client_dev *client)
> +{
> + struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
> +
> + drm_fb_helper_unprepare(fb_helper);
> + kfree(fb_helper);
> +}
> +
> static void drm_fbdev_client_unregister(struct drm_client_dev *client)
> {
> struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
>
> if (fb_helper->info) {
> + /*
> + * Fully probed framebuffer device
> + */
> drm_fb_helper_unregister_info(fb_helper);
> } else {
> + /*
> + * Partially initialized client, no framebuffer device yet
> + */
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
> }
>
> @@ -88,6 +100,7 @@ static int drm_fbdev_client_resume(struct drm_client_dev *client, bool holds_con
>
> static const struct drm_client_funcs drm_fbdev_client_funcs = {
> .owner = THIS_MODULE,
> + .free = drm_fbdev_client_free,
> .unregister = drm_fbdev_client_unregister,
> .restore = drm_fbdev_client_restore,
> .hotplug = drm_fbdev_client_hotplug,
> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> index 3fa38d4ac70b..fe9c6d7083ea 100644
> --- a/drivers/gpu/drm/drm_client.c
> +++ b/drivers/gpu/drm/drm_client.c
> @@ -168,6 +168,10 @@ void drm_client_release(struct drm_client_dev *client)
>
> drm_client_modeset_free(client);
> drm_client_close(client);
> +
> + if (client->funcs && client->funcs->free)
> + client->funcs->free(client);
> +
> drm_dev_put(dev);
> }
> EXPORT_SYMBOL(drm_client_release);
> diff --git a/drivers/gpu/drm/drm_fbdev_dma.c b/drivers/gpu/drm/drm_fbdev_dma.c
> index 8bd626ef16c7..c6196293e424 100644
> --- a/drivers/gpu/drm/drm_fbdev_dma.c
> +++ b/drivers/gpu/drm/drm_fbdev_dma.c
> @@ -57,8 +57,6 @@ static void drm_fbdev_dma_fb_destroy(struct fb_info *info)
> drm_client_buffer_vunmap(fb_helper->buffer);
> drm_client_framebuffer_delete(fb_helper->buffer);
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops drm_fbdev_dma_fb_ops = {
> @@ -92,8 +90,6 @@ static void drm_fbdev_dma_shadowed_fb_destroy(struct fb_info *info)
> drm_client_buffer_vunmap(fb_helper->buffer);
> drm_client_framebuffer_delete(fb_helper->buffer);
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops drm_fbdev_dma_shadowed_fb_ops = {
> diff --git a/drivers/gpu/drm/drm_fbdev_shmem.c b/drivers/gpu/drm/drm_fbdev_shmem.c
> index 1e827bf8b815..51573058df6f 100644
> --- a/drivers/gpu/drm/drm_fbdev_shmem.c
> +++ b/drivers/gpu/drm/drm_fbdev_shmem.c
> @@ -65,8 +65,6 @@ static void drm_fbdev_shmem_fb_destroy(struct fb_info *info)
> drm_client_buffer_vunmap(fb_helper->buffer);
> drm_client_framebuffer_delete(fb_helper->buffer);
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops drm_fbdev_shmem_fb_ops = {
> diff --git a/drivers/gpu/drm/drm_fbdev_ttm.c b/drivers/gpu/drm/drm_fbdev_ttm.c
> index 85feb55bba11..ccf460fbc1f0 100644
> --- a/drivers/gpu/drm/drm_fbdev_ttm.c
> +++ b/drivers/gpu/drm/drm_fbdev_ttm.c
> @@ -53,8 +53,6 @@ static void drm_fbdev_ttm_fb_destroy(struct fb_info *info)
> drm_client_framebuffer_delete(fb_helper->buffer);
>
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops drm_fbdev_ttm_fb_ops = {
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> index 93de25b77e68..a3bd21a827ad 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> @@ -42,8 +42,6 @@ static void exynos_drm_fb_destroy(struct fb_info *info)
> drm_framebuffer_remove(fb);
>
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops exynos_drm_fb_ops = {
> diff --git a/drivers/gpu/drm/gma500/fbdev.c b/drivers/gpu/drm/gma500/fbdev.c
> index a6af21514cff..bc92fa24a1e2 100644
> --- a/drivers/gpu/drm/gma500/fbdev.c
> +++ b/drivers/gpu/drm/gma500/fbdev.c
> @@ -84,9 +84,6 @@ static void psb_fbdev_fb_destroy(struct fb_info *info)
> drm_gem_object_put(obj);
>
> drm_client_release(&fb_helper->client);
> -
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops psb_fbdev_fb_ops = {
> diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
> index 3fbdf75415cc..d5f26c8bb102 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbdev.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
> @@ -146,8 +146,6 @@ static void intel_fbdev_fb_destroy(struct fb_info *info)
> drm_framebuffer_remove(fb_helper->fb);
>
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> __diag_push();
> diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
> index b5969374d53f..aad6fb77f0de 100644
> --- a/drivers/gpu/drm/msm/msm_fbdev.c
> +++ b/drivers/gpu/drm/msm/msm_fbdev.c
> @@ -52,8 +52,6 @@ static void msm_fbdev_fb_destroy(struct fb_info *info)
> drm_framebuffer_remove(fb);
>
> drm_client_release(&helper->client);
> - drm_fb_helper_unprepare(helper);
> - kfree(helper);
> }
>
> static const struct fb_ops msm_fb_ops = {
> diff --git a/drivers/gpu/drm/omapdrm/omap_fbdev.c b/drivers/gpu/drm/omapdrm/omap_fbdev.c
> index 948af7ec1130..b5df2923d2a6 100644
> --- a/drivers/gpu/drm/omapdrm/omap_fbdev.c
> +++ b/drivers/gpu/drm/omapdrm/omap_fbdev.c
> @@ -103,8 +103,6 @@ static void omap_fbdev_fb_destroy(struct fb_info *info)
> drm_framebuffer_remove(fb);
>
> drm_client_release(&helper->client);
> - drm_fb_helper_unprepare(helper);
> - kfree(helper);
> }
>
> /*
> diff --git a/drivers/gpu/drm/radeon/radeon_fbdev.c b/drivers/gpu/drm/radeon/radeon_fbdev.c
> index dc81b0c2dbff..4df6c9167bf0 100644
> --- a/drivers/gpu/drm/radeon/radeon_fbdev.c
> +++ b/drivers/gpu/drm/radeon/radeon_fbdev.c
> @@ -184,8 +184,6 @@ static void radeon_fbdev_fb_destroy(struct fb_info *info)
> radeon_fbdev_destroy_pinned_object(gobj);
>
> drm_client_release(&fb_helper->client);
> - drm_fb_helper_unprepare(fb_helper);
> - kfree(fb_helper);
> }
>
> static const struct fb_ops radeon_fbdev_fb_ops = {
> diff --git a/drivers/gpu/drm/tegra/fbdev.c b/drivers/gpu/drm/tegra/fbdev.c
> index 1b70f5e164af..91aece6f34e0 100644
> --- a/drivers/gpu/drm/tegra/fbdev.c
> +++ b/drivers/gpu/drm/tegra/fbdev.c
> @@ -53,8 +53,6 @@ static void tegra_fbdev_fb_destroy(struct fb_info *info)
> drm_framebuffer_remove(fb);
>
> drm_client_release(&helper->client);
> - drm_fb_helper_unprepare(helper);
> - kfree(helper);
> }
>
> static const struct fb_ops tegra_fb_ops = {
> diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h
> index bdd845e383ef..eecb8d6e15c7 100644
> --- a/include/drm/drm_client.h
> +++ b/include/drm/drm_client.h
> @@ -28,6 +28,16 @@ struct drm_client_funcs {
> */
> struct module *owner;
>
> + /**
> + * @free:
> + *
> + * Called when the client gets unregistered. Implementations should
> + * release all client-specific data and free the memory.
> + *
> + * This callback is optional.
> + */
> + void (*free)(struct drm_client_dev *client);
> +
> /**
> * @unregister:
> *
> --
> 2.51.0
>
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