[RFC 5/9] drivers: platform: Configure dma operations at probe time

Sricharan R sricharan at codeaurora.org
Mon Apr 25 08:58:10 PDT 2016


From: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>

Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
---
 drivers/base/platform.c | 13 +++++++++++++
 drivers/of/platform.c   |  7 +++----
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index f437afa..17e64a4 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -557,6 +557,12 @@ static int platform_drv_probe(struct device *_dev)
 	if (ret < 0)
 		return ret;
 
+	if (of_have_populated_dt()) {
+		ret = of_dma_configure_ops(_dev, _dev->of_node);
+		if (ret < 0)
+			goto done;
+	}
+
 	ret = dev_pm_domain_attach(_dev, true);
 	if (ret != -EPROBE_DEFER) {
 		if (drv->probe) {
@@ -569,6 +575,11 @@ static int platform_drv_probe(struct device *_dev)
 		}
 	}
 
+	if (of_have_populated_dt()) {
+		if (ret)
+			of_dma_deconfigure(_dev);
+	}
+done:
 	if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
 		dev_warn(_dev, "probe deferral not supported\n");
 		ret = -ENXIO;
@@ -591,6 +602,8 @@ static int platform_drv_remove(struct device *_dev)
 	if (drv->remove)
 		ret = drv->remove(dev);
 	dev_pm_domain_detach(_dev, true);
+	if (of_have_populated_dt())
+		of_dma_deconfigure(_dev);
 
 	return ret;
 }
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 17ee8d5..12bbc8e1 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -180,11 +180,9 @@ static struct platform_device *of_platform_device_create_pdata(
 	dev->dev.bus = &platform_bus_type;
 	dev->dev.platform_data = platform_data;
 	of_dma_configure_masks(&dev->dev, dev->dev.of_node);
-	of_dma_configure_ops(&dev->dev, dev->dev.of_node);
 	of_msi_configure(&dev->dev, dev->dev.of_node);
 
 	if (of_device_add(dev) != 0) {
-		of_dma_deconfigure(&dev->dev);
 		platform_device_put(dev);
 		goto err_clear_flag;
 	}
@@ -481,11 +479,12 @@ static int of_platform_device_destroy(struct device *dev, void *data)
 	if (dev->bus == &platform_bus_type)
 		platform_device_unregister(to_platform_device(dev));
 #ifdef CONFIG_ARM_AMBA
-	else if (dev->bus == &amba_bustype)
+	else if (dev->bus == &amba_bustype) {
 		amba_device_unregister(to_amba_device(dev));
+		of_dma_deconfigure(dev);
+	}
 #endif
 
-	of_dma_deconfigure(dev);
 	of_node_clear_flag(dev->of_node, OF_POPULATED);
 	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
 	return 0;
-- 
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