[PATCH] mmc: pxamci: fix the device-tree probe deferral path

[PATCH] mmc: pxamci: fix the device-tree probe deferral path

[Robert Jarzmik]

When the gpio driver is probed after the mmc one, the read/write gpio
and card detection one return -EPROBE_DEFER. Unfortunately, the memory
region remains requested, and upon the next probe, the probe will fail
anyway with -EBUSY.

Fix this by releasing the memory resource upon probe failure.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
---
 drivers/mmc/host/pxamci.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 28a057fae0a1..405ec339a1b8 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -657,7 +657,7 @@ static int pxamci_probe(struct platform_device *pdev)
 	if (!r || irq < 0)
 		return -ENXIO;
 
-	r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
+	r = devm_request_mem_region(&pdev->dev, r->start, SZ_4K, DRIVER_NAME);
 	if (!r)
 		return -EBUSY;
 
@@ -840,7 +840,6 @@ out:
 	}
 	if (mmc)
 		mmc_free_host(mmc);
-	release_resource(r);
 	return ret;
 }
 
-- 
2.1.4

Re: [PATCH] mmc: pxamci: fix the device-tree probe deferral path

[Ulf Hansson]

On 3 February 2016 at 23:19, Robert Jarzmik <robert.jarzmik@free.fr> wrote:
> When the gpio driver is probed after the mmc one, the read/write gpio
> and card detection one return -EPROBE_DEFER. Unfortunately, the memory
> region remains requested, and upon the next probe, the probe will fail
> anyway with -EBUSY.
>
> Fix this by releasing the memory resource upon probe failure.
>
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> ---
>  drivers/mmc/host/pxamci.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
> index 28a057fae0a1..405ec339a1b8 100644
> --- a/drivers/mmc/host/pxamci.c
> +++ b/drivers/mmc/host/pxamci.c
> @@ -657,7 +657,7 @@ static int pxamci_probe(struct platform_device *pdev)
>         if (!r || irq < 0)
>                 return -ENXIO;
>
> -       r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
> +       r = devm_request_mem_region(&pdev->dev, r->start, SZ_4K, DRIVER_NAME);

I suggest you replace also the ioremap call, thus using
devm_ioremap_resource() is convenient.

>         if (!r)
>                 return -EBUSY;
>
> @@ -840,7 +840,6 @@ out:
>         }
>         if (mmc)
>                 mmc_free_host(mmc);
> -       release_resource(r);

This looks wrong.

>         return ret;
>  }
>
> --
> 2.1.4
>

Perhaps it's just easier to convert the probe function to use all
devm_* functions, as for example irqs isn't freed either.

In that way, you will solve all problems of also leaking memory in one go.

Kind regards
Uffe

Re: [PATCH] mmc: pxamci: fix the device-tree probe deferral path

[Robert Jarzmik]

Ulf Hansson <ulf.hansson@linaro.org> writes:

> On 3 February 2016 at 23:19, Robert Jarzmik <robert.jarzmik@free.fr> wrote:
>> When the gpio driver is probed after the mmc one, the read/write gpio
>> and card detection one return -EPROBE_DEFER. Unfortunately, the memory
>> region remains requested, and upon the next probe, the probe will fail
>> anyway with -EBUSY.
>>
>> Fix this by releasing the memory resource upon probe failure.
>>
>> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
>> ---
>>  drivers/mmc/host/pxamci.c | 3 +--
>>  1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
>> index 28a057fae0a1..405ec339a1b8 100644
>> --- a/drivers/mmc/host/pxamci.c
>> +++ b/drivers/mmc/host/pxamci.c
>> @@ -657,7 +657,7 @@ static int pxamci_probe(struct platform_device *pdev)
>>         if (!r || irq < 0)
>>                 return -ENXIO;
>>
>> -       r = request_mem_region(r->start, SZ_4K, DRIVER_NAME);
>> +       r = devm_request_mem_region(&pdev->dev, r->start, SZ_4K, DRIVER_NAME);
>
> I suggest you replace also the ioremap call, thus using
> devm_ioremap_resource() is convenient.
Yes, of course, for v2.

>> @@ -840,7 +840,6 @@ out:
>>         }
>>         if (mmc)
>>                 mmc_free_host(mmc);
>> -       release_resource(r);
>
> This looks wrong.
Hum. Why so ?

> Perhaps it's just easier to convert the probe function to use all
> devm_* functions, as for example irqs isn't freed either.
You're very right.
Actually the first patch I had was with devm_irq_request(), and then I reverted
that chunk, thinking I was overdoing it, and that this didn't belong to this
commit.
Silly me, hein ?

> In that way, you will solve all problems of also leaking memory in one go.
Sure.

Cheers.

-- 
Robert