• Thomas Zimmermann's avatar
    drm/msm: Implement fbdev emulation as in-kernel client · 940b869c
    Thomas Zimmermann authored
    Move code from ad-hoc fbdev callbacks into DRM client functions
    and remove the old callbacks. The functions instruct the client
    to poll for changed output or restore the display. The DRM core
    calls both, the old callbacks and the new client helpers, from
    the same places. The new functions perform the same operation as
    before, so there's no change in functionality.
    
    Replace all code that initializes or releases fbdev emulation
    throughout the driver. Instead initialize the fbdev client by a
    single call to msm_fbdev_setup() after msm has registered its
    DRM device. As in most drivers, msm's fbdev emulation now acts
    like a regular DRM client.
    
    The fbdev client setup consists of the initial preparation and the
    hot-plugging of the display. The latter creates the fbdev device
    and sets up the fbdev framebuffer. The setup performs display
    hot-plugging once. If no display can be detected, DRM probe helpers
    re-run the detection on each hotplug event.
    
    A call to drm_dev_unregister() releases the client automatically.
    No further action is required within msm. If the fbdev framebuffer
    has been fully set up, struct fb_ops.fb_destroy implements the
    release. For partially initialized emulation, the fbdev client
    reverts the initial setup.
    
    v2:
    	* handle fbdev module parameter correctly (kernel test robot)
    Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
    Reviewed-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
    Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> # RB5
    Patchwork: https://patchwork.freedesktop.org/patch/530560/
    Link: https://lore.kernel.org/r/20230403124538.8497-9-tzimmermann@suse.deSigned-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
    940b869c
msm_fbdev.c 5.78 KB