[PATCH v2] DRM: Add DRM kms/fb cma helper

[Sascha Hauer]

On Wed, May 30, 2012 at 05:30:15PM +0200, Lars-Peter Clausen wrote:
> This patch introduces a set of helper function for implementing the KMS
> framebuffer layer for drivers which use the drm gem CMA helper function.
> 
> Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
> 
> ---
> Changes since v1:
> 	* Some spelling fixes
> 	* Add missing kfree in drm_fb_cma_alloc error path
> 	* Add multi-plane support. drm_fb_cma_get_gem_obj now takes a second
> 	  parameter to specify the plane.
> ---
>  drivers/gpu/drm/Kconfig             |   11 +
>  drivers/gpu/drm/Makefile            |    1 +
>  drivers/gpu/drm/drm_fb_cma_helper.c |  384 +++++++++++++++++++++++++++++++++++
>  include/drm/drm_fb_cma_helper.h     |   27 +++
>  4 files changed, 423 insertions(+)
>  create mode 100644 drivers/gpu/drm/drm_fb_cma_helper.c
>  create mode 100644 include/drm/drm_fb_cma_helper.h
> 
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index a78dfbe..e7c0a3d 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -41,6 +41,17 @@ config DRM_GEM_CMA_HELPER
>  	help
>  	  Choose this if you need the GEM cma helper functions
>  
> +config DRM_KMS_CMA_HELPER
> +	tristate
> +	select DRM_GEM_CMA_HELPER
> +	select DRM_KMS_HELPER
> +	select FB_SYS_FILLRECT
> +	select FB_SYS_COPYAREA
> +	select FB_SYS_IMAGEBLIT
> +	help
> +	  Choose this if you need the KMS cma helper functions
> +
> +
>  config DRM_TDFX
>  	tristate "3dfx Banshee/Voodoo3+"
>  	depends on DRM && PCI
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index 6e9e948..5dcb1a5 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -18,6 +18,7 @@ drm-$(CONFIG_COMPAT) += drm_ioc32.o
>  drm-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_gem_cma_helper.o
>  
>  drm_kms_helper-y := drm_fb_helper.o drm_crtc_helper.o drm_dp_i2c_helper.o
> +drm_kms_helper-$(CONFIG_DRM_KMS_CMA_HELPER) += drm_fb_cma_helper.o
>  
>  obj-$(CONFIG_DRM_KMS_HELPER) += drm_kms_helper.o
>  
> diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
> new file mode 100644
> index 0000000..8821a98
> --- /dev/null
> +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> @@ -0,0 +1,384 @@
> +/*
> + * drm kms/fb cma (contiguous memory allocator) helper functions
> + *
> + * Copyright (C) 2012 Analog Device Inc.
> + *   Author: Lars-Peter Clausen <lars at metafoo.de>
> + *
> + * Based on udl_fbdev.c
> + *  Copyright (C) 2012 Red Hat
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version 2
> + * of the License, or (at your option) any later version.
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_fb_cma_helper.h>
> +#include <linux/module.h>
> +
> +struct drm_fb_cma {
> +	struct drm_framebuffer	fb;
> +	struct drm_gem_cma_obj	*obj[4];

Can we have a define for this magic '4'? It is used several times in
this patch.

> +static struct drm_fb_cma *drm_fb_cma_alloc(struct drm_device *dev,
> +	struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_cma_obj **obj,
> +	unsigned int num_planes)
> +{
> +	struct drm_fb_cma *fb_cma;
> +	int ret;
> +	int i;
> +
> +	fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
> +	if (!fb_cma)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ret = drm_framebuffer_init(dev, &fb_cma->fb, &drm_fb_cma_funcs);
> +	if (ret) {
> +		dev_err(dev->dev, "Failed to initalize framebuffer: %d\n", ret);
> +		kfree(fb_cma);
> +		return ERR_PTR(ret);
> +	}
> +
> +	drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
> +
> +	for (i = 0; i < num_planes; i++)
> +		fb_cma->obj[i] = obj[i];

Check for valid num_planes before this loop?


Note I have renamed struct drm_gem_cma_obj to struct drm_gem_cma_object
in the patch I just sent.

Sascha

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