On Tue, Sep 15, 2015 at 04:55:02PM -0700, Rafael Antognolli wrote: > This list will be used to get the aux channels registered through the > helpers. One function is provided to set a callback for added/removed > aux channels, and another function to iterate over the list of aux > channels. > > Signed-off-by: Rafael Antognolli <rafael.antognolli@xxxxxxxxx> > --- > drivers/gpu/drm/drm_dp_helper.c | 73 +++++++++++++++++++++++++++++++++++++++++ > include/drm/drm_dp_helper.h | 5 +++ > 2 files changed, 78 insertions(+) > > diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c > index 9535c5b..41bdd93 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -746,6 +746,56 @@ static const struct i2c_algorithm drm_dp_i2c_algo = { > .master_xfer = drm_dp_i2c_xfer, > }; > > +struct drm_dp_aux_node { > + struct klist_node list; > + struct drm_dp_aux *aux; > +}; > + > +static DEFINE_KLIST(drm_dp_aux_list, NULL, NULL); > + > +static int (*aux_dev_cb)(int action, struct drm_dp_aux *aux) = NULL; > + > +void drm_dp_aux_set_aux_dev(int (*fn)(int, struct drm_dp_aux *)) > +{ > + aux_dev_cb = fn; > +} > +EXPORT_SYMBOL(drm_dp_aux_set_aux_dev); > + > +static struct drm_dp_aux *next_aux(struct klist_iter *i) > +{ > + struct klist_node *n = klist_next(i); > + struct drm_dp_aux *aux = NULL; > + struct drm_dp_aux_node *aux_node; > + > + if (n) { > + aux_node = container_of(n, struct drm_dp_aux_node, list); > + aux = aux_node->aux; > + } > + return aux; > +} > + > +int drm_dp_aux_for_each(void *data, int (*fn)(struct drm_dp_aux *, void *)) > +{ > + struct klist_iter i; > + struct drm_dp_aux *aux; > + int error = 0; > + > + klist_iter_init(&drm_dp_aux_list, &i); > + while ((aux = next_aux(&i)) && !error) > + error = fn(aux, data); > + klist_iter_exit(&i); > + return error; > +} > +EXPORT_SYMBOL(drm_dp_aux_for_each); > + > +static int drm_dp_aux_dev_inform(int action, struct drm_dp_aux *aux) > +{ > + if (aux_dev_cb) { > + return aux_dev_cb(action, aux); > + } > + return 0; > +} > + > /** > * drm_dp_aux_register() - initialise and register aux channel > * @aux: DisplayPort AUX channel > @@ -754,6 +804,7 @@ static const struct i2c_algorithm drm_dp_i2c_algo = { > */ > int drm_dp_aux_register(struct drm_dp_aux *aux) > { > + struct drm_dp_aux_node *aux_node; > mutex_init(&aux->hw_mutex); > > aux->ddc.algo = &drm_dp_i2c_algo; > @@ -768,6 +819,14 @@ int drm_dp_aux_register(struct drm_dp_aux *aux) > strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), > sizeof(aux->ddc.name)); > > + /* add aux to list and notify listeners */ > + aux_node = kzalloc(sizeof(*aux_node), GFP_KERNEL); > + if (!aux_node) > + return -ENOMEM; > + aux_node->aux = aux; > + klist_add_tail(&aux_node->list, &drm_dp_aux_list); > + drm_dp_aux_dev_inform(DRM_DP_ADD_AUX, aux); If you go with the direct function call approach there's no need for all this indirection, just do something like drm_dp_aux_register_devnode(aux); And drop all the list book-keeping (since there will never be a time when the aux stuff isn't loaded yet). Essentially you're reinventing notifier chains here (but without the required locking). With that this patch just adds 2 lines, probably best to squash it in with the last one. -Daniel > + > return i2c_add_adapter(&aux->ddc); > } > EXPORT_SYMBOL(drm_dp_aux_register); > @@ -778,6 +837,20 @@ EXPORT_SYMBOL(drm_dp_aux_register); > */ > void drm_dp_aux_unregister(struct drm_dp_aux *aux) > { > + struct klist_iter i; > + struct klist_node *n; > + > + klist_iter_init(&drm_dp_aux_list, &i); > + while ((n = klist_next(&i))) { > + struct drm_dp_aux_node *aux_node = > + container_of(n, struct drm_dp_aux_node, list); > + if (aux_node->aux == aux) { > + klist_del(n); > + kfree(aux_node); > + break; > + } > + } > + drm_dp_aux_dev_inform(DRM_DP_DEL_AUX, aux); > i2c_del_adapter(&aux->ddc); > } > EXPORT_SYMBOL(drm_dp_aux_unregister); > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h > index 9ec4716..f92de26 100644 > --- a/include/drm/drm_dp_helper.h > +++ b/include/drm/drm_dp_helper.h > @@ -763,7 +763,12 @@ int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link); > int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link); > int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link); > > +#define DRM_DP_ADD_AUX 0x01 > +#define DRM_DP_DEL_AUX 0x02 > + > int drm_dp_aux_register(struct drm_dp_aux *aux); > void drm_dp_aux_unregister(struct drm_dp_aux *aux); > +void drm_dp_aux_set_aux_dev(int (*fn)(int, struct drm_dp_aux *)); > +int drm_dp_aux_for_each(void *data, int (*fn)(struct drm_dp_aux *, void *)); > > #endif /* _DRM_DP_HELPER_H_ */ > -- > 2.4.3 > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel