[PATCH v2 05/20] drm/colorop: Create drm_atomic_helper_colorop_create_state()

[Maxime Ripard <mripard@kernel.org>]

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.

And reset() isn't fallible, which makes it harder to handle
initialization errors properly.

It's also only relevant for some drivers, 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.

Let's continue the transition to the new pattern with drm_colorop.

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(+)

diff --git a/drivers/gpu/drm/drm_colorop.c b/drivers/gpu/drm/drm_colorop.c
index 6a26b83b260e8d8e83c703ecde490a7a8740ebfb..7bfaf2617ec315f42d80ac72a5eaaef868e65657 100644
--- a/drivers/gpu/drm/drm_colorop.c
+++ b/drivers/gpu/drm/drm_colorop.c
@@ -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
  *
diff --git a/include/drm/drm_colorop.h b/include/drm/drm_colorop.h
index bd082854ca74cac90b42020b09206a8516687666..874ed693329c0ecf94567c094744fe86fd08e382 100644
--- a/include/drm/drm_colorop.h
+++ b/include/drm/drm_colorop.h
@@ -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);

-- 
2.53.0