[PATCH 50/51] drm/udl: drop drm_driver.release hook

[Daniel Vetter]

On Fri, Feb 28, 2020 at 12:46 PM Thomas Zimmermann <tzimmermann at suse.de> wrote:
>
> Hi
>
> Am 28.02.20 um 09:40 schrieb Daniel Vetter:
> > On Fri, Feb 28, 2020 at 8:44 AM Thomas Zimmermann <tzimmermann at suse.de> wrote:
> >>
> >> Hi Daniel
> >>
> >> Am 27.02.20 um 19:15 schrieb Daniel Vetter:
> >>> There's only two functions called from that:
> >>> drm_kms_helper_poll_fini() and udl_free_urb_list(). Both of these are
> >>> also called from the ubs_driver->disconnect hook, so entirely
> >>> pointless to do the same again in the ->release hook.
> >>
> >> The disconnect hook calls drm_kms_helper_poll_disable() instead if
> >> _fini(). They are the same, except that _disable() does not clear
> >> dev->mode_config.poll_enabled to false. Is this OK?
> >
> > oops, I overlooked that. But yeah for driver shutdown it's the same
> > really, we're not going to re-enable. _disable is meant for suspend so
> > youc an re-enable again on resume.
> >
> > I'll augment the commit message on the next round to clarify that.
>
> Well, we have a managed API. It could support
> drmm_kms_helper_poll_init(). :)

You're ahead of the game here, but yes that's the plan. And a lot
more. Ideally I really want to get rid of both bus_driver->remove and
drm_driver->release callbacks for all drivers.

Also, for polling you actually want devm_kms_poll_init, since polling
should be stopped at unplug/remove time. Not at drm_driver release
time :-)
-Daniel

>
> Best regards
> Thomas
>
> > -Daniel
> >
> >
> >> Best regards
> >> Thomas
> >>
> >>>
> >>> Furthermore by the time we clean up the drm_driver we really shouldn't
> >>> be touching hardware anymore, so stopping the poll worker and freeing
> >>> the urb allocations in ->disconnect is the right thing to do.
> >>>
> >>> Now disconnect still cleans things up before unregistering the driver,
> >>> but that's a different issue.
> >>>
> >>> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> >>> Cc: Dave Airlie <airlied at redhat.com>
> >>> Cc: Sean Paul <sean at poorly.run>
> >>> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> >>> Cc: Thomas Zimmermann <tzimmermann at suse.de>
> >>> Cc: Emil Velikov <emil.l.velikov at gmail.com>
> >>> Cc: Gerd Hoffmann <kraxel at redhat.com>
> >>> Cc: "Noralf Trønnes" <noralf at tronnes.org>
> >>> Cc: Sam Ravnborg <sam at ravnborg.org>
> >>> Cc: Thomas Gleixner <tglx at linutronix.de>
> >>> Cc: Alex Deucher <alexander.deucher at amd.com>
> >>> ---
> >>>  drivers/gpu/drm/udl/udl_drv.c  |  6 ------
> >>>  drivers/gpu/drm/udl/udl_drv.h  |  1 -
> >>>  drivers/gpu/drm/udl/udl_main.c | 10 ----------
> >>>  3 files changed, 17 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/udl/udl_drv.c b/drivers/gpu/drm/udl/udl_drv.c
> >>> index b447fb053e78..7f140898df3e 100644
> >>> --- a/drivers/gpu/drm/udl/udl_drv.c
> >>> +++ b/drivers/gpu/drm/udl/udl_drv.c
> >>> @@ -34,14 +34,8 @@ static int udl_usb_resume(struct usb_interface *interface)
> >>>
> >>>  DEFINE_DRM_GEM_FOPS(udl_driver_fops);
> >>>
> >>> -static void udl_driver_release(struct drm_device *dev)
> >>> -{
> >>> -     udl_fini(dev);
> >>> -}
> >>> -
> >>>  static struct drm_driver driver = {
> >>>       .driver_features = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
> >>> -     .release = udl_driver_release,
> >>>
> >>>       /* gem hooks */
> >>>       .gem_create_object = udl_driver_gem_create_object,
> >>> diff --git a/drivers/gpu/drm/udl/udl_drv.h b/drivers/gpu/drm/udl/udl_drv.h
> >>> index 1de7eb1b6aac..2642f94a63fc 100644
> >>> --- a/drivers/gpu/drm/udl/udl_drv.h
> >>> +++ b/drivers/gpu/drm/udl/udl_drv.h
> >>> @@ -76,7 +76,6 @@ int udl_submit_urb(struct drm_device *dev, struct urb *urb, size_t len);
> >>>  void udl_urb_completion(struct urb *urb);
> >>>
> >>>  int udl_init(struct udl_device *udl);
> >>> -void udl_fini(struct drm_device *dev);
> >>>
> >>>  int udl_render_hline(struct drm_device *dev, int log_bpp, struct urb **urb_ptr,
> >>>                    const char *front, char **urb_buf_ptr,
> >>> diff --git a/drivers/gpu/drm/udl/udl_main.c b/drivers/gpu/drm/udl/udl_main.c
> >>> index 538718919916..f5d27f2a5654 100644
> >>> --- a/drivers/gpu/drm/udl/udl_main.c
> >>> +++ b/drivers/gpu/drm/udl/udl_main.c
> >>> @@ -351,13 +351,3 @@ int udl_drop_usb(struct drm_device *dev)
> >>>       udl_free_urb_list(dev);
> >>>       return 0;
> >>>  }
> >>> -
> >>> -void udl_fini(struct drm_device *dev)
> >>> -{
> >>> -     struct udl_device *udl = to_udl(dev);
> >>> -
> >>> -     drm_kms_helper_poll_fini(dev);
> >>> -
> >>> -     if (udl->urbs.count)
> >>> -             udl_free_urb_list(dev);
> >>> -}
> >>>
> >>
> >> --
> >> Thomas Zimmermann
> >> Graphics Driver Developer
> >> SUSE Software Solutions Germany GmbH
> >> Maxfeldstr. 5, 90409 Nürnberg, Germany
> >> (HRB 36809, AG Nürnberg)
> >> Geschäftsführer: Felix Imendörffer
> >>
> >
> >
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Felix Imendörffer
>


-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch