ACPI: Retire acpi_iommu_fwspec_ops()

Now that iommu_fwspec_init() can signal for probe deferral directly,
acpi_iommu_fwspec_ops() is unneeded and can be cleaned up.
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/011e39e275aba3ad451c5a1965ca8ddf20ed36c2.1719919669.git.robin.murphy@arm.comSigned-off-by: Will Deacon <will@kernel.org>

drivers/acpi/scan.c

@@ -1588,26 +1588,14 @@ int acpi_iommu_fwspec_init(struct device *dev, u32 id,
 	return iommu_fwspec_add_ids(dev, &id, 1);
 }
 
-static inline const struct iommu_ops *acpi_iommu_fwspec_ops(struct device *dev)
-{
-	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
-
-	return fwspec ? fwspec->ops : NULL;
-}
-
 static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
 {
 	int err;
-	const struct iommu_ops *ops;
 
 	/* Serialise to make dev->iommu stable under our potential fwspec */
 	mutex_lock(&iommu_probe_device_lock);
-	/*
-	 * If we already translated the fwspec there is nothing left to do,
-	 * return the iommu_ops.
-	 */
-	ops = acpi_iommu_fwspec_ops(dev);
-	if (ops) {
+	/* If we already translated the fwspec there is nothing left to do */
+	if (dev_iommu_fwspec_get(dev)) {
 		mutex_unlock(&iommu_probe_device_lock);
 		return 0;
 	}
@@ -1624,15 +1612,7 @@ static int acpi_iommu_configure_id(struct device *dev, const u32 *id_in)
 	if (!err && dev->bus)
 		err = iommu_probe_device(dev);
 
-	if (err == -EPROBE_DEFER)
-		return err;
-	if (err) {
-		dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
-		return err;
-	}
-	if (!acpi_iommu_fwspec_ops(dev))
-		return -ENODEV;
-	return 0;
+	return err;
 }
 
 #else /* !CONFIG_IOMMU_API */
@@ -1672,6 +1652,8 @@ int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
 	ret = acpi_iommu_configure_id(dev, input_id);
 	if (ret == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
+	if (ret)
+		dev_dbg(dev, "Adding to IOMMU failed: %d\n", ret);
 
 	arch_setup_dma_ops(dev, attr == DEV_DMA_COHERENT);