Re: [PATCH V4 4/6] iommu/arm-smmu: Add the device_link between masters and smmu

From: Stephen Boyd
Date: Wed Jul 12 2017 - 18:55:55 EST


On 07/06, Vivek Gautam wrote:
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index ddbfa8ab69e6..75567d9698ab 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -1348,6 +1348,7 @@ static int arm_smmu_add_device(struct device *dev)
> struct arm_smmu_device *smmu;
> struct arm_smmu_master_cfg *cfg;
> struct iommu_fwspec *fwspec = dev->iommu_fwspec;
> + struct device_link *link = NULL;

Unnecessary initialization?

> int i, ret;
>
> if (using_legacy_binding) {
> @@ -1403,6 +1404,16 @@ static int arm_smmu_add_device(struct device *dev)
>
> pm_runtime_put_sync(smmu->dev);
>
> + /*
> + * Establish the link between smmu and master, so that the
> + * smmu gets runtime enabled/disabled as per the master's
> + * needs.
> + */
> + link = device_link_add(dev, smmu->dev, DL_FLAG_PM_RUNTIME);
> + if (!link)
> + dev_warn(smmu->dev, "Unable to create device link between %s and %s\n",
> + dev_name(smmu->dev), dev_name(dev));
> +
> return 0;
>

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project