Hi Rafael, On 2019-01-29 00:05, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > > The device links used by rockchip-iommu and exynos-iommu are > completely managed by these drivers within the IOMMU framework, > so there is no reason to involve the driver core in the management > of these links. > > For this reason, make rockchip-iommu and exynos-iommu pass > DL_FLAG_STATELESS in flags to device_link_add(), so that the device > links used by them are stateless. > > [Note that this change is requisite for a subsequent one that will > rework the management of stateful device links in the driver core > and it will not be compatible with the two drivers in question any > more.] > > Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Indeed there is no need to use driver-state tracking feature of device links in this case. For the Exynos IOMMU driver: Acked-by: Marek Szyprowski <m.szyprow...@samsung.com> > --- > drivers/iommu/exynos-iommu.c | 1 + > drivers/iommu/rockchip-iommu.c | 3 ++- > 2 files changed, 3 insertions(+), 1 deletion(-) > > Index: linux-pm/drivers/iommu/rockchip-iommu.c > =================================================================== > --- linux-pm.orig/drivers/iommu/rockchip-iommu.c > +++ linux-pm/drivers/iommu/rockchip-iommu.c > @@ -1071,7 +1071,8 @@ static int rk_iommu_add_device(struct de > iommu_group_put(group); > > iommu_device_link(&iommu->iommu, dev); > - data->link = device_link_add(dev, iommu->dev, DL_FLAG_PM_RUNTIME); > + data->link = device_link_add(dev, iommu->dev, > + DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME); > > return 0; > } > Index: linux-pm/drivers/iommu/exynos-iommu.c > =================================================================== > --- linux-pm.orig/drivers/iommu/exynos-iommu.c > +++ linux-pm/drivers/iommu/exynos-iommu.c > @@ -1260,6 +1260,7 @@ static int exynos_iommu_add_device(struc > * direct calls to pm_runtime_get/put in this driver. > */ > data->link = device_link_add(dev, data->sysmmu, > + DL_FLAG_STATELESS | > DL_FLAG_PM_RUNTIME); > } > iommu_group_put(group); > > > Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
