Re: [PATCH v2 09/13] iommu/rockchip: Use iommu_group_get_for_dev() for add_device

[JeffyChen]

On 01/17/2018 08:47 PM, JeffyChen wrote:
> > > +static struct iommu_group *rk_iommu_device_group(struct device *dev)
> > > +{
> > > +    struct iommu_group *group;
> > > +    int ret;
> > > +
> > > +    group = iommu_group_get(dev);
> > > +    if (!group) {
> >
> > This check is pointless - if dev->iommu_group were non-NULL you wouldn't
> > have been called in the first place.
> right, it's allocated in the probe.
oops, sorry, i see, this is not needed because device_group() is only be 
called when iommu_group_get() returns NULL