drm/fb-helper: Add multi buffer support for cma fbdev
authorXinliang Liu <xinliang.liu@linaro.org>
Wed, 15 Feb 2017 16:19:08 +0000 (17:19 +0100)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Sun, 26 Feb 2017 21:11:37 +0000 (22:11 +0100)
commit5f15257689bfaacfc1ecd7d91a2e0515a5d3d104
treed2d9814c69e62d8322f3551183a96a9a71420156
parentcd2523569a733d85788b6fc016e4e23cb3549a25
drm/fb-helper: Add multi buffer support for cma fbdev

This patch add a config to support to create multi buffer for cma fbdev.
Such as double buffer and triple buffer.

Cma fbdev is convient to add a legency fbdev. And still many Android
devices use fbdev now and at least double buffer is needed for these
Android devices, so that a buffer flip can be operated. It will need
some time for Android device vendors to abondon legency fbdev. So multi
buffer for fbdev is needed.

Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org>
[s.christ@phytec.de: Picking patch from
                     https://lkml.org/lkml/2015/9/14/188]
Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/075ffb50cc16ab055b5d47b30163401bb356ab51.1487175046.git-series.maxime.ripard@free-electrons.com
drivers/gpu/drm/Kconfig
drivers/gpu/drm/drm_fb_helper.c