staging: iio: Introduce the use of devm_ioremap_resource

This patch introduces the use of devm_ioremap_resource. It does away
with call to request_mem_region and the error checking on
platform_get_resource. Also, the calls to free the allocated resources
like release_mem_region and iounmap are done away with. The ret variable
in the probe function is also eliminated. Also, a bug is fixed as the
goto in the error handling of request_mem_region should not have
called release_mem_region which releases a resource that has not been
allocated.

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/staging/iio/adc/ad7606_par.c b/drivers/staging/iio/adc/ad7606_par.c
index 8a48d18..7511839 100644 (file)
--- a/drivers/staging/iio/adc/ad7606_par.c
+++ b/drivers/staging/iio/adc/ad7606_par.c
@@ -53,7 +53,7 @@ static int ad7606_par_probe(struct platform_device *pdev)
        struct iio_dev *indio_dev;
        void __iomem *addr;
        resource_size_t remap_size;
-       int ret, irq;
+       int irq;
 
        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {
@@ -62,56 +62,31 @@ static int ad7606_par_probe(struct platform_device *pdev)
        }
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       if (!res)
-               return -ENODEV;
+       addr = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(addr))
+               return PTR_ERR(addr);
 
        remap_size = resource_size(res);
 
-       /* Request the regions */
-       if (!request_mem_region(res->start, remap_size, "iio-ad7606")) {
-               ret = -EBUSY;
-               goto out1;
-       }
-       addr = ioremap(res->start, remap_size);
-       if (!addr) {
-               ret = -ENOMEM;
-               goto out1;
-       }
-
        indio_dev = ad7606_probe(&pdev->dev, irq, addr,
                          platform_get_device_id(pdev)->driver_data,
                          remap_size > 1 ? &ad7606_par16_bops :
                          &ad7606_par8_bops);
 
-       if (IS_ERR(indio_dev))  {
-               ret = PTR_ERR(indio_dev);
-               goto out2;
-       }
+       if (IS_ERR(indio_dev))
+               return PTR_ERR(indio_dev);
 
        platform_set_drvdata(pdev, indio_dev);
 
        return 0;
-
-out2:
-       iounmap(addr);
-out1:
-       release_mem_region(res->start, remap_size);
-
-       return ret;
 }
 
 static int ad7606_par_remove(struct platform_device *pdev)
 {
        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
-       struct resource *res;
-       struct ad7606_state *st = iio_priv(indio_dev);
 
        ad7606_remove(indio_dev, platform_get_irq(pdev, 0));
 
-       iounmap(st->base_address);
-       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       release_mem_region(res->start, resource_size(res));
-
        return 0;
 }