iommu/omap: Allow enable/disable even without pdata

When booting with a devicetree, no platform data is provided.
Do not prematurely exit iommu_enable() and iommu_disable() in
such a case.

Note: As OMAP do not yet has a proper reset controller driver,
IOMMUs requiring a reset signal should use pdata-quirks as a
transitional solution.

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Signed-off-by: Suman Anna <s-anna@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>

drivers/iommu/omap-iommu.c

@@ -146,13 +146,10 @@ static int iommu_enable(struct omap_iommu *obj)
 	struct platform_device *pdev = to_platform_device(obj->dev);
 	struct iommu_platform_data *pdata = pdev->dev.platform_data;
 
-	if (!pdata)
-		return -EINVAL;
-
 	if (!arch_iommu)
 		return -ENODEV;
 
-	if (pdata->deassert_reset) {
+	if (pdata && pdata->deassert_reset) {
 		err = pdata->deassert_reset(pdev, pdata->reset_name);
 		if (err) {
 			dev_err(obj->dev, "deassert_reset failed: %d\n", err);
@@ -172,14 +169,11 @@ static void iommu_disable(struct omap_iommu *obj)
 	struct platform_device *pdev = to_platform_device(obj->dev);
 	struct iommu_platform_data *pdata = pdev->dev.platform_data;
 
-	if (!pdata)
-		return;
-
 	arch_iommu->disable(obj);
 
 	pm_runtime_put_sync(obj->dev);
 
-	if (pdata->assert_reset)
+	if (pdata && pdata->assert_reset)
 		pdata->assert_reset(pdev, pdata->reset_name);
 }