[PATCH] drm: Lighten sysfs connector 'status'

[Daniel Vetter]

On Fri, Mar 06, 2015 at 08:58:40AM -0500, Alex Deucher wrote:
> On Fri, Mar 6, 2015 at 7:36 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > Since the beginning, sysfs/connector/status has done a heavyweight
> > detection of the current connector status. But no user, such as upowerd
> > or logind, has ever desired to initiate a probe. Move the probing into a
> > new attribute so that existing readers get the behaviour they desire.
> >
> > v2: David Herrmann suggested using "echo detect > /sys/.../status" to
> > trigger the probing, which is a fine idea. This extends that to also
> > allow the user to apply the force detection overrides at runtime.
> >
> > v3: Now with airlied's email address fixed! Requires sysfs_streq()
> >
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> > Cc: David Herrmann <dh.herrmann at gmail.com>
> > Cc: Dave Airlie <airlied at redhat.com>
> > Cc: Alex Deucher <alexdeucher at gmail.com>
> 
> Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

Merged to drm-misc, thanks.
-Daniel

> 
> > ---
> >  drivers/gpu/drm/drm_sysfs.c | 61 +++++++++++++++++++++++++++++++++++++++------
> >  1 file changed, 53 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
> > index 5c99d3773212..ffc305fc2076 100644
> > --- a/drivers/gpu/drm/drm_sysfs.c
> > +++ b/drivers/gpu/drm/drm_sysfs.c
> > @@ -166,23 +166,68 @@ void drm_sysfs_destroy(void)
> >  /*
> >   * Connector properties
> >   */
> > -static ssize_t status_show(struct device *device,
> > +static ssize_t status_store(struct device *device,
> >                            struct device_attribute *attr,
> > -                          char *buf)
> > +                          const char *buf, size_t count)
> >  {
> >         struct drm_connector *connector = to_drm_connector(device);
> > -       enum drm_connector_status status;
> > +       struct drm_device *dev = connector->dev;
> > +       enum drm_connector_status old_status;
> >         int ret;
> >
> > -       ret = mutex_lock_interruptible(&connector->dev->mode_config.mutex);
> > +       ret = mutex_lock_interruptible(&dev->mode_config.mutex);
> >         if (ret)
> >                 return ret;
> >
> > -       status = connector->funcs->detect(connector, true);
> > -       mutex_unlock(&connector->dev->mode_config.mutex);
> > +       old_status = connector->status;
> > +
> > +       if (sysfs_streq(buf, "detect")) {
> > +               connector->force = 0;
> > +               connector->status = connector->funcs->detect(connector, true);
> > +       } else if (sysfs_streq(buf, "on")) {
> > +               connector->force = DRM_FORCE_ON;
> > +       } else if (sysfs_streq(buf, "on-digital")) {
> > +               connector->force = DRM_FORCE_ON_DIGITAL;
> > +       } else if (sysfs_streq(buf, "off")) {
> > +               connector->force = DRM_FORCE_OFF;
> > +       } else
> > +               ret = -EINVAL;
> > +
> > +       if (ret == 0 && connector->force) {
> > +               if (connector->force == DRM_FORCE_ON ||
> > +                   connector->force == DRM_FORCE_ON_DIGITAL)
> > +                       connector->status = connector_status_connected;
> > +               else
> > +                       connector->status = connector_status_disconnected;
> > +               if (connector->funcs->force)
> > +                       connector->funcs->force(connector);
> > +       }
> > +
> > +       if (old_status != connector->status) {
> > +               DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n",
> > +                             connector->base.id,
> > +                             connector->name,
> > +                             old_status, connector->status);
> > +
> > +               dev->mode_config.delayed_event = true;
> > +               if (dev->mode_config.poll_enabled)
> > +                       schedule_delayed_work(&dev->mode_config.output_poll_work,
> > +                                             0);
> > +       }
> > +
> > +       mutex_unlock(&dev->mode_config.mutex);
> > +
> > +       return ret;
> > +}
> > +
> > +static ssize_t status_show(struct device *device,
> > +                          struct device_attribute *attr,
> > +                          char *buf)
> > +{
> > +       struct drm_connector *connector = to_drm_connector(device);
> >
> >         return snprintf(buf, PAGE_SIZE, "%s\n",
> > -                       drm_get_connector_status_name(status));
> > +                       drm_get_connector_status_name(connector->status));
> >  }
> >
> >  static ssize_t dpms_show(struct device *device,
> > @@ -339,7 +384,7 @@ static ssize_t select_subconnector_show(struct device *device,
> >                         drm_get_dvi_i_select_name((int)subconnector));
> >  }
> >
> > -static DEVICE_ATTR_RO(status);
> > +static DEVICE_ATTR_RW(status);
> >  static DEVICE_ATTR_RO(enabled);
> >  static DEVICE_ATTR_RO(dpms);
> >  static DEVICE_ATTR_RO(modes);
> > --
> > 2.1.4
> >

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