[PATCH] drivers/dma/sirf-dma.c: fix usage of devm functions

[Julia Lawall]

From: Julia Lawall <Julia.Lawall at lip6.fr>

Fix some problems with the use of devm_ functions.

devm_kzalloc: devm_kfree is not needed

devm_ioremap: iounmap should not be used, no free is needed

devm_request_irq: the devm_free_irq is followed by irq_dispose_mapping.  I
don't know if it is safe to move the freeing of the irq in this case, so I
have just un-devm'd this function, since the implicit freeing is never
taken advantage of.

In the original code failure of of_address_to_resource jumped to free_mem,
but should have jumped to irq_dispose, since irq_of_parse_and_map has
completed at this point.

In the original code unmap_mem was after irq_dispose, but it should have
been before, again since irq_of_parse_and_map has completed at this point.

One of these problems was found using the following semantic match:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

*x = devm_ioremap(...)
...
iounmap(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall at lip6.fr>

---
Not compiled.  Does free_irq actually have to be called before
irq_dispose_mapping?

 drivers/dma/sirf-dma.c |   23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c
index 434ad31..1af9e48 100644
--- a/drivers/dma/sirf-dma.c
+++ b/drivers/dma/sirf-dma.c
@@ -570,21 +570,19 @@ static int __devinit sirfsoc_dma_probe(struct platform_device *op)
 
 	if (of_property_read_u32(dn, "cell-index", &id)) {
 		dev_err(dev, "Fail to get DMAC index\n");
-		ret = -ENODEV;
-		goto free_mem;
+		return -ENODEV;
 	}
 
 	sdma->irq = irq_of_parse_and_map(dn, 0);
 	if (sdma->irq == NO_IRQ) {
 		dev_err(dev, "Error mapping IRQ!\n");
-		ret = -EINVAL;
-		goto free_mem;
+		return -EINVAL;
 	}
 
 	ret = of_address_to_resource(dn, 0, &res);
 	if (ret) {
 		dev_err(dev, "Error parsing memory region!\n");
-		goto free_mem;
+		goto irq_dispose;
 	}
 
 	regs_start = res.start;
@@ -597,12 +595,11 @@ static int __devinit sirfsoc_dma_probe(struct platform_device *op)
 		goto irq_dispose;
 	}
 
-	ret = devm_request_irq(dev, sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME,
-		sdma);
+	ret = request_irq(sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, sdma);
 	if (ret) {
 		dev_err(dev, "Error requesting IRQ!\n");
 		ret = -EINVAL;
-		goto unmap_mem;
+		goto irq_dispose;
 	}
 
 	dma = &sdma->dma;
@@ -652,13 +649,9 @@ static int __devinit sirfsoc_dma_probe(struct platform_device *op)
 	return 0;
 
 free_irq:
-	devm_free_irq(dev, sdma->irq, sdma);
+	free_irq(sdma->irq, sdma);
 irq_dispose:
 	irq_dispose_mapping(sdma->irq);
-unmap_mem:
-	iounmap(sdma->base);
-free_mem:
-	devm_kfree(dev, sdma);
 	return ret;
 }
 
@@ -668,10 +661,8 @@ static int __devexit sirfsoc_dma_remove(struct platform_device *op)
 	struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
 
 	dma_async_device_unregister(&sdma->dma);
-	devm_free_irq(dev, sdma->irq, sdma);
+	free_irq(sdma->irq, sdma);
 	irq_dispose_mapping(sdma->irq);
-	iounmap(sdma->base);
-	devm_kfree(dev, sdma);
 	return 0;
 }