[RFC PATCH 2/3] drm/fb-cma-helper: expose more of fb cma guts

From: Peter Rosin
Date: Fri Jun 16 2017 - 05:12:16 EST


DRM drivers supporting clut may want a convenient way to only use
non-default .gamma_set and .gamma_get ops in the drm_fb_helper_funcs
in order to avoid the following

/*
* The driver really shouldn't advertise pseudo/directcolor
* visuals if it can't deal with the palette.
*/
if (WARN_ON(!fb_helper->funcs->gamma_set ||
!fb_helper->funcs->gamma_get))
return -EINVAL;

warning in drm_fb_helper.c:setcolreg().

Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
---
drivers/gpu/drm/drm_fb_cma_helper.c | 55 ++++++++++++++++++++++++++++++-------
include/drm/drm_fb_cma_helper.h | 8 +++++-
2 files changed, 52 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
index 53f9bdf..ef96227 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -426,7 +426,12 @@ static void drm_fbdev_cma_defio_fini(struct fb_info *fbi)
kfree(fbi->fbops);
}

-static int
+/**
+ * drm_fbdev_cma_create() - Default fb_probe() function for fb_cma_helper_funcs
+ * @helper: The fb_helper to create a cma for
+ * @sizes: The fbdev sizes
+ */
+int
drm_fbdev_cma_create(struct drm_fb_helper *helper,
struct drm_fb_helper_surface_size *sizes)
{
@@ -507,23 +512,28 @@ drm_fbdev_cma_create(struct drm_fb_helper *helper,
drm_gem_object_put_unlocked(&obj->base);
return ret;
}
+EXPORT_SYMBOL_GPL(drm_fbdev_cma_create);

static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
.fb_probe = drm_fbdev_cma_create,
};

/**
- * drm_fbdev_cma_init_with_funcs() - Allocate and initializes a drm_fbdev_cma struct
+ * drm_fbdev_cma_init_with_funcs2() - Allocate and initializes a drm_fbdev_cma struct
* @dev: DRM device
* @preferred_bpp: Preferred bits per pixel for the device
* @max_conn_count: Maximum number of connectors
- * @funcs: fb helper functions, in particular a custom dirty() callback
+ * @framebuffer_funcs: framebuffer functions, in particular a custom dirty() callback
+ * @fb_helper_funcs: fb helper functions, in particular custom gamma_set() and gamma_get() callbacks
+ *
+ * If framebuffer_funcs or fb_helper_funcs are NULL, default functions are used.
*
* Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
*/
-struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
+struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs2(struct drm_device *dev,
unsigned int preferred_bpp, unsigned int max_conn_count,
- const struct drm_framebuffer_funcs *funcs)
+ const struct drm_framebuffer_funcs *framebuffer_funcs,
+ const struct drm_fb_helper_funcs *fb_helper_funcs)
{
struct drm_fbdev_cma *fbdev_cma;
struct drm_fb_helper *helper;
@@ -534,11 +544,17 @@ struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
return ERR_PTR(-ENOMEM);
}
- fbdev_cma->fb_funcs = funcs;
+
+ if (!framebuffer_funcs)
+ framebuffer_funcs = &drm_fb_cma_funcs;
+ if (!fb_helper_funcs)
+ fb_helper_funcs = &drm_fb_cma_helper_funcs;
+
+ fbdev_cma->fb_funcs = framebuffer_funcs;

helper = &fbdev_cma->fb_helper;

- drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
+ drm_fb_helper_prepare(dev, helper, fb_helper_funcs);

ret = drm_fb_helper_init(dev, helper, max_conn_count);
if (ret < 0) {
@@ -568,6 +584,25 @@ struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,

return ERR_PTR(ret);
}
+EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs2);
+
+/**
+ * drm_fbdev_cma_init_with_funcs() - Allocate and initializes a drm_fbdev_cma struct
+ * @dev: DRM device
+ * @preferred_bpp: Preferred bits per pixel for the device
+ * @max_conn_count: Maximum number of connectors
+ * @framebuffer_funcs: framebuffer functions, in particular a custom dirty() callback
+ *
+ * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
+ */
+struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
+ unsigned int preferred_bpp, unsigned int max_conn_count,
+ const struct drm_framebuffer_funcs *framebuffer_funcs)
+{
+ return drm_fbdev_cma_init_with_funcs2(dev, preferred_bpp,
+ max_conn_count,
+ framebuffer_funcs, NULL);
+}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs);

/**
@@ -581,9 +616,9 @@ EXPORT_SYMBOL_GPL(drm_fbdev_cma_init_with_funcs);
struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
unsigned int preferred_bpp, unsigned int max_conn_count)
{
- return drm_fbdev_cma_init_with_funcs(dev, preferred_bpp,
- max_conn_count,
- &drm_fb_cma_funcs);
+ return drm_fbdev_cma_init_with_funcs2(dev, preferred_bpp,
+ max_conn_count,
+ NULL, NULL);
}
EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);

diff --git a/include/drm/drm_fb_cma_helper.h b/include/drm/drm_fb_cma_helper.h
index 199a63f..280ec2b 100644
--- a/include/drm/drm_fb_cma_helper.h
+++ b/include/drm/drm_fb_cma_helper.h
@@ -15,13 +15,19 @@ struct drm_mode_fb_cmd2;
struct drm_plane;
struct drm_plane_state;

+struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs2(struct drm_device *dev,
+ unsigned int preferred_bpp, unsigned int max_conn_count,
+ const struct drm_framebuffer_funcs *framebuffer_funcs,
+ const struct drm_fb_helper_funcs *fb_helper_funcs);
struct drm_fbdev_cma *drm_fbdev_cma_init_with_funcs(struct drm_device *dev,
unsigned int preferred_bpp, unsigned int max_conn_count,
- const struct drm_framebuffer_funcs *funcs);
+ const struct drm_framebuffer_funcs *framebuffer_funcs);
struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
unsigned int preferred_bpp, unsigned int max_conn_count);
void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma);

+int drm_fbdev_cma_create(struct drm_fb_helper *helper,
+ struct drm_fb_helper_surface_size *sizes);
void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma);
void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma);
void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, int state);
--
2.1.4