a796ba2cb3
Instead of assigning/clearing the crtc on vblank enable/disable, we can just assign and clear the crtc on modeset. That allows us to just toggle the encoder's vblank interrupts on vblank_enable. So why is this important? Previously the driver was using the legacy pointers to assign/clear the crtc. Legacy pointers are cleared _after_ disabling the hardware, so the legacy pointer was valid during vblank_disable, but that's not something we should rely on. Instead of relying on the core ordering the legacy pointer assignments just so, we'll assign the crtc in dpu_crtc enable/disable. This is the only place that mapping can change, so we're covered there. We're also taking advantage of drm_crtc_vblank_on/off. By using this, we ensure that vblank_enable/disable can never be called while the crtc is off (which means the assigned crtc will always be valid). As such, we don't need to use modeset locks or the crtc_lock in the vblank_enable/disable routine to be sure state is consistent. ...I think. Changes in v2: - Changed crtc check in toggle_vblank to != (Jeykumar) Cc: Jeykumar Sankaran <jsanka@codeaurora.org> Reviewed-by: Jeykumar Sankaran <jsanka@codeaurora.org> Signed-off-by: Sean Paul <seanpaul@chromium.org> [dpu_crtc.c change needed to be manually applied b/c of the dpu_crtc_reset change] Signed-off-by: Rob Clark <robdclark@gmail.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.