[PATCH v2 00/11] drm/tinydrm: Support device unplug

[Daniel Vetter]

Hi Noralf,

On Fri, Sep 08, 2017 at 05:07:19PM +0200, Noralf Trønnes wrote:
> This adds device unplug support to drm_fb_helper, drm_fb_cma_helper
> (fbdev) and tinydrm.
> 
> There are several changes in this version:
> 
> I've used Daniel's idea of protecting drm_device.unplugged with srcu to
> provide race free drm_dev_unplug().
> 
> The fbdev helper unplug patch has become very small with Daniel's help.
> Ref is now taken and dropped in the existing helpers, so I could drop
> drm_fb_helper_simple_init().
> 
> I has annoyed me that fbdev is restored in drm_driver.last_close even if
> fbdev isn't used. I've added a patch to fix that. This means I can drop
> calling drm_atomic_helper_shutdown() in tinydrm_unregister(), since I
> now can easily disable the pipeline from userspace by just closing the
> users. Disabled pipeline means balanced regulator_enable/disable.
> 
> The 'Embed drm_device in tinydrm_device' patch has gained
> drm_driver.release functions after a discussion with Laurent. My
> previous version relied on obscure freeing in tinydrm_release().
> This means that I didn't retain the ack's.
> 
> Laurent also caught an ugly devm_kmalloc() in
> tinydrm_display_pipe_init() that I've fixed.

I'm practically packing for my 2 weeks of conference travel already, so
only very cursory read of the initial patches for core&fb-helpers. I think
this looks really splendid now.

But I won't have time for review for the next few week, would be good if
you could drag some others into this discussions. Iirc there's recently
been a few different people interested in udl (even some patches I think),
they might be able to help out with testing&review.

Also, would be great if you can submit this to intel-gfx on the next
round, so that our CI can pick it up and give it a solid beating. Touching
critical core paths like in patch 1 is always a bit scary.

Thanks, Daniel

> 
> Noralf.
> 
> Noralf Trønnes (11):
>   drm: Use srcu to protect drm_device.unplugged
>   drm/fb-helper: Support device unplug
>   drm/fb-helper: Ensure driver module is pinned in fb_open()
>   drm/fb-helper: Don't restore if fbdev is not in use
>   drm/fb-cma-helper: Make struct drm_fbdev_cma public
>   drm/fb-cma-helper: Support device unplug
>   drm/tinydrm: Drop driver registered message
>   drm/tinydrm: Embed drm_device in tinydrm_device
>   drm/tinydrm: Support device unplug in core
>   drm/tinydrm/mi0283qt: Let the display pipe handle power
>   drm/tinydrm: Support device unplug in drivers
> 
>  drivers/gpu/drm/drm_drv.c                   |  54 +++++++++--
>  drivers/gpu/drm/drm_fb_cma_helper.c         |  13 +--
>  drivers/gpu/drm/drm_fb_helper.c             | 108 ++++++++++++++++++++--
>  drivers/gpu/drm/tinydrm/core/tinydrm-core.c | 135 +++++++++++++++++++---------
>  drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c |  28 +++---
>  drivers/gpu/drm/tinydrm/mi0283qt.c          |  81 +++++------------
>  drivers/gpu/drm/tinydrm/mipi-dbi.c          |  58 +++++++++---
>  drivers/gpu/drm/tinydrm/repaper.c           |  62 ++++++++-----
>  drivers/gpu/drm/tinydrm/st7586.c            |  54 ++++++-----
>  include/drm/drm_device.h                    |   9 +-
>  include/drm/drm_drv.h                       |  15 +++-
>  include/drm/drm_fb_cma_helper.h             |  11 ++-
>  include/drm/drm_fb_helper.h                 |  28 ++++++
>  include/drm/tinydrm/mipi-dbi.h              |   1 +
>  include/drm/tinydrm/tinydrm.h               |  10 ++-
>  15 files changed, 469 insertions(+), 198 deletions(-)
> 
> -- 
> 2.7.4
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch