[v6,07/19] drm/colorop: Create drm_atomic_helper_colorop_create_state()
Commit Message
Commit 47b5ac7daa46 ("drm/atomic: Add new atomic_create_state callback
to drm_private_obj") introduced a new pattern for allocating drm object
states.
Instead of relying on the reset() callback, it created a new
atomic_create_state hook. This is helpful because reset is a bit
overloaded: it's used to create the initial software state, reset it,
but also reset the hardware.
It can also be used either at probe time, to create the initial state
and possibly reset the hardware to an expected default, but also during
suspend/resume.
Both these cases come with different expectations too: during the
initialization, we want to initialize all states, but during
suspend/resume, drm_private_states for example are expected to be kept
around.
reset() also isn't fallible, which makes it harder to handle
initialization errors properly. This is only really relevant for some
drivers though, since all the helpers for reset only create a new
state, and don't touch the hardware at all.
It was thus decided to create a new hook that would allocate and
initialize a pristine state without any side effect:
atomic_create_state to untangle a bit some of it, and to separate the
initialization with the actual reset one might need during a
suspend/resume.
Continue the transition to the new pattern with drm_colorop.
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
drivers/gpu/drm/drm_colorop.c | 23 +++++++++++++++++++++++
include/drm/drm_colorop.h | 2 ++
2 files changed, 25 insertions(+)
Comments
Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] The commit introduces `drm_atomic_helper_colorop_create_state` but fails to add the `atomic_create_state` hook to `struct drm_colorop_funcs` or wire it into the core logic.
- [Low] The newly added helper function `drm_atomic_helper_colorop_create_state` lacks an EXPORT_SYMBOL declaration.
--
commit 523a46597f73af1e23a2580a6ff384bfca9c08b5
Author: Maxime Ripard <mripard@kernel.org>
drm/colorop: Create drm_atomic_helper_colorop_create_state()
This commit introduces a new helper function,
drm_atomic_helper_colorop_create_state(), to allocate and initialize a
pristine colorop atomic state without side effects. It is intended to separate
initialization from hardware reset operations.
> Continue the transition to the new pattern with drm_colorop.
[Severity: Medium]
Does this commit miss adding the atomic_create_state function pointer to
struct drm_colorop_funcs and wiring it into the core logic?
Unlike the equivalent patches for planes and CRTCs, the hook is not added,
and functions like drm_colorop_reset() continue to hardcode state allocations
via kzalloc. This leaves the new helper as unimplemented dead code, meaning
the transition described in the commit message is incomplete.
> diff --git a/drivers/gpu/drm/drm_colorop.c b/drivers/gpu/drm/drm_colorop.c
> index 4c4d0a953e357..c0eecde8c1762 100644
> --- a/drivers/gpu/drm/drm_colorop.c
> +++ b/drivers/gpu/drm/drm_colorop.c
> @@ -523,6 +523,29 @@ static void __drm_colorop_state_init(struct drm_colorop_state *colorop_state,
[ ... ]
> +struct drm_colorop_state *
> +drm_atomic_helper_colorop_create_state(struct drm_colorop *colorop)
> +{
> + struct drm_colorop_state *state;
> +
> + state = kzalloc_obj(*state);
> + if (!state)
> + return ERR_PTR(-ENOMEM);
> +
> + __drm_colorop_state_init(state, colorop);
> +
> + return state;
> +}
[Severity: Low]
Since this is a core DRM helper intended for drivers to plug into their
function tables, should there be an EXPORT_SYMBOL() or EXPORT_SYMBOL_GPL()
declaration here?
Without it, any driver built as a loadable module that attempts to use this
new helper will fail to build due to unresolved symbol linker errors.
@@ -521,10 +521,33 @@ static void __drm_colorop_state_init(struct drm_colorop_state *colorop_state,
&val))
colorop_state->curve_1d_type = val;
}
}
+/**
+ * drm_atomic_helper_colorop_create_state - Allocates and initializes colorop atomic state
+ * @colorop: drm colorop
+ *
+ * Initializes a pristine @drm_colorop_state.
+ *
+ * RETURNS:
+ * Pointer to new colorop state, or ERR_PTR on failure.
+ */
+struct drm_colorop_state *
+drm_atomic_helper_colorop_create_state(struct drm_colorop *colorop)
+{
+ struct drm_colorop_state *state;
+
+ state = kzalloc_obj(*state);
+ if (!state)
+ return ERR_PTR(-ENOMEM);
+
+ __drm_colorop_state_init(state, colorop);
+
+ return state;
+}
+
/**
* __drm_colorop_reset - reset state on colorop
* @colorop: drm colorop
* @colorop_state: colorop state to assign
*
@@ -423,10 +423,12 @@ int drm_plane_colorop_3dlut_init(struct drm_device *dev, struct drm_colorop *col
struct drm_plane *plane, const struct drm_colorop_funcs *funcs,
uint32_t lut_size,
enum drm_colorop_lut3d_interpolation_type interpolation,
uint32_t flags);
+struct drm_colorop_state *
+drm_atomic_helper_colorop_create_state(struct drm_colorop *colorop);
struct drm_colorop_state *
drm_atomic_helper_colorop_duplicate_state(struct drm_colorop *colorop);
void drm_colorop_atomic_destroy_state(struct drm_colorop *colorop,
struct drm_colorop_state *state);