Re: [PATCH] iio: adc: exynos5_adc: fix compilation warnings

From: Naveen Krishna Ch
Date: Wed Mar 06 2013 - 08:15:29 EST


On 6 March 2013 17:44, Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
> On 03/06/2013 05:11 AM, Naveen Krishna Chatradhi wrote:
>> From: Naveen Krishna Ch <ch.naveen@xxxxxxxxxxx>
>>
>> Fixes the compilation warnings and potential NULL pointer
>> dereferencing pointed out by "Dan Carpenter".
>>
>
> I'd say that's a rather un-potential NULL pointer dereferencing, but if it
> makes the static checkers happy, why not. Since the same match table is used to
> match the device, probe won't be called unless there is a match, so
> of_match_node() will never return NULL in this case.
Right, i was thinking how it is such a potential error.
Anyway, Dan's suggestion of Kconfig change holds very good.
I will submit v2, with the appropriate changes.

>
>> Signed-off-by: Naveen Krishna Ch <ch.naveen@xxxxxxxxxxx>
>> ---
>> drivers/iio/adc/exynos_adc.c | 24 +++++++++++++++++-------
>> 1 file changed, 17 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
>> index ed6fdd7..67d07aa 100644
>> --- a/drivers/iio/adc/exynos_adc.c
>> +++ b/drivers/iio/adc/exynos_adc.c
>> @@ -92,7 +92,7 @@ struct exynos_adc {
>> struct completion completion;
>>
>> u32 value;
>> - unsigned int version;
>> + unsigned int version;
>> };
>>
>> static const struct of_device_id exynos_adc_match[] = {
>> @@ -102,12 +102,15 @@ static const struct of_device_id exynos_adc_match[] = {
>> };
>> MODULE_DEVICE_TABLE(of, exynos_adc_match);
>>
>> -static inline unsigned int exynos_adc_get_version(struct platform_device *pdev)
>> +static inline int exynos_adc_get_version(struct platform_device *pdev)
>> {
>> const struct of_device_id *match;
>>
>> match = of_match_node(exynos_adc_match, pdev->dev.of_node);
>> - return (unsigned int)match->data;
>> + if (!match)
>> + return -ENODEV;
>> +
>> + return (int)match->data;
>> }
>>
>> static int exynos_read_raw(struct iio_dev *indio_dev,
>> @@ -117,7 +120,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
>> long mask)
>> {
>> struct exynos_adc *info = iio_priv(indio_dev);
>> - unsigned long timeout;
>> + int timeout;
>> u32 con1, con2;
>>
>> if (mask != IIO_CHAN_INFO_RAW)
>> @@ -255,7 +258,7 @@ static int exynos_adc_probe(struct platform_device *pdev)
>> struct iio_dev *indio_dev = NULL;
>> struct resource *mem;
>> int ret = -ENODEV;
>> - int irq;
>> + int irq, version;
>>
>> if (!np)
>> return ret;
>> @@ -268,6 +271,15 @@ static int exynos_adc_probe(struct platform_device *pdev)
>>
>> info = iio_priv(indio_dev);
>>
>> + version = exynos_adc_get_version(pdev);
>> + if (version < 0) {
>> + dev_err(&pdev->dev, "no matching of_node, err = %d\n", version);
>> + ret = version;
>> + goto err_iio;
>> + }
>> +
>> + info->version = version;
>> +
>> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>
>> info->regs = devm_request_and_ioremap(&pdev->dev, mem);
>> @@ -311,8 +323,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
>> goto err_irq;
>> }
>>
>> - info->version = exynos_adc_get_version(pdev);
>> -
>> platform_set_drvdata(pdev, indio_dev);
>>
>> indio_dev->name = dev_name(&pdev->dev);
>



--
Shine bright,
(: Nav :)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/