From: Arindam Nath <arindam.nath@amd.com>
Date: Tue, 18 Sep 2018 15:40:58 +0530
Subject: iommu/amd: Return devid as alias for ACPI HID devices
Git-commit: 5ebb1bc2d63d90dd204169e21fd7a0b4bb8c776e
Patch-mainline: v4.19-rc6
References: bsc#1106105

ACPI HID devices do not actually have an alias for
them in the IVRS. But dev_data->alias is still used
for indexing into the IOMMU device table for devices
being handled by the IOMMU. So for ACPI HID devices,
we simply return the corresponding devid as an alias,
as parsed from IVRS table.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Fixes: 2bf9a0a12749 ('iommu/amd: Add iommu support for ACPI HID devices')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/amd_iommu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 4e04fff23977..73e47d93e7a0 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -246,7 +246,13 @@ static u16 get_alias(struct device *dev)
 
 	/* The callers make sure that get_device_id() does not fail here */
 	devid = get_device_id(dev);
+
+	/* For ACPI HID devices, we simply return the devid as such */
+	if (!dev_is_pci(dev))
+		return devid;
+
 	ivrs_alias = amd_iommu_alias_table[devid];
+
 	pci_for_each_dma_alias(pdev, __last_alias, &pci_alias);
 
 	if (ivrs_alias == pci_alias)