[PATCH v12 3/4] iommu/arm-smmu: Add the device_link between masters and smmu

From: Vivek Gautam
Date: Sun Jul 08 2018 - 13:34:55 EST


From: Sricharan R <sricharan@xxxxxxxxxxxxxx>

Finally add the device link between the master device and
smmu, so that the smmu gets runtime enabled/disabled only when the
master needs it. This is done from add_device callback which gets
called once when the master is added to the smmu.

Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
Reviewed-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
Cc: Rafael J. Wysocki <rjw@xxxxxxxxxxxxx>
Cc: Lukas Wunner <lukas@xxxxxxxxx>
---

- Change since v11
* Replaced DL_FLAG_AUTOREMOVE flag with DL_FLAG_AUTOREMOVE_SUPPLIER.

drivers/iommu/arm-smmu.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 09265e206e2d..916cde4954d2 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1461,8 +1461,20 @@ static int arm_smmu_add_device(struct device *dev)

iommu_device_link(&smmu->iommu, dev);

+ if (pm_runtime_enabled(smmu->dev) &&
+ !device_link_add(dev, smmu->dev,
+ DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER)) {
+ dev_err(smmu->dev, "Unable to add link to the consumer %s\n",
+ dev_name(dev));
+ ret = -ENODEV;
+ goto out_unlink;
+ }
+
return 0;

+out_unlink:
+ iommu_device_unlink(&smmu->iommu, dev);
+ arm_smmu_master_free_smes(fwspec);
out_cfg_free:
kfree(cfg);
out_free:
--
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