[PATCH] drm/msm: Implement msm drm fb_mmap callback function

[hali at codeaurora.org]

Re-send the patch to remove the unnecessary initialization and the comment

> This change implements msm drm specific fb_mmap function for fb device
> to properly map the fb address to userspace.
>
> Signed-off-by: Hai Li <hali at codeaurora.org>
> Signed-off-by: Stephane Viau <sviau at codeaurora.org>
> ---
>  drivers/gpu/drm/msm/msm_fbdev.c | 38
> ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 36 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_fbdev.c
> b/drivers/gpu/drm/msm/msm_fbdev.c
> index a752ab8..2694e90 100644
> --- a/drivers/gpu/drm/msm/msm_fbdev.c
> +++ b/drivers/gpu/drm/msm/msm_fbdev.c
> @@ -19,6 +19,11 @@
>
>  #include "drm_crtc.h"
>  #include "drm_fb_helper.h"
> +#include "msm_gem.h"
> +
> +extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
> +					struct vm_area_struct *vma);
> +static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct
> *vma);
>
>  /*
>   * fbdev funcs, to implement legacy fbdev interface on top of drm driver
> @@ -43,6 +48,7 @@ static struct fb_ops msm_fb_ops = {
>  	.fb_fillrect = sys_fillrect,
>  	.fb_copyarea = sys_copyarea,
>  	.fb_imageblit = sys_imageblit,
> +	.fb_mmap = msm_fbdev_mmap,
>
>  	.fb_check_var = drm_fb_helper_check_var,
>  	.fb_set_par = drm_fb_helper_set_par,
> @@ -51,6 +57,31 @@ static struct fb_ops msm_fb_ops = {
>  	.fb_setcmap = drm_fb_helper_setcmap,
>  };
>
> +static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct
> *vma)
> +{
> +	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
> +	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
> +	struct drm_gem_object *drm_obj = fbdev->bo;
> +	struct drm_device *dev = helper->dev;
> +	int ret;
> +
> +	if (drm_device_is_unplugged(dev))
> +		return -ENODEV;
> +
> +	mutex_lock(&dev->struct_mutex);
> +
> +	ret = drm_gem_mmap_obj(drm_obj, drm_obj->size, vma);
> +
> +	mutex_unlock(&dev->struct_mutex);
> +
> +	if (ret) {
> +		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
> +		return ret;
> +	}
> +
> +	return msm_gem_mmap_obj(drm_obj, vma);
> +}
> +
>  static int msm_fbdev_create(struct drm_fb_helper *helper,
>  		struct drm_fb_helper_surface_size *sizes)
>  {
> @@ -104,8 +135,11 @@ static int msm_fbdev_create(struct drm_fb_helper
> *helper,
>
>  	mutex_lock(&dev->struct_mutex);
>
> -	/* TODO implement our own fb_mmap so we don't need this: */
> -	msm_gem_get_iova_locked(fbdev->bo, 0, &paddr);
> +	ret = msm_gem_get_iova_locked(fbdev->bo, 0, &paddr);
> +	if (ret) {
> +		dev_err(dev->dev, "failed to get buffer obj iova: %d\n", ret);
> +		goto fail;
> +	}
>
>  	fbi = framebuffer_alloc(0, dev->dev);
>  	if (!fbi) {
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
>
>