[alsa-devel] [PATCH] ASoC: cs4271: free reset gpio in cs4271_remove()

Wed Feb 19 13:09:27 CET 2014

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On 02/19/2014 12:43 PM, Mark Brown wrote:
> On Wed, Feb 19, 2014 at 12:24:23PM +0100, Daniel Mack wrote:
>> On 02/19/2014 12:15 PM, Mark Brown wrote:
>>> On Wed, Feb 19, 2014 at 12:07:12PM +0100, Daniel Mack wrote:
> 
>>>> +	if (gpio_is_valid(cs4271->gpio_nreset)) { /* Set codec to
>>>> the reset state */ gpio_set_value(cs4271->gpio_nreset, 0); +
>>>> devm_gpio_free(codec->dev, cs4271->gpio_nreset); +	}
> 
>>> If it's being requested as a managed resource shouldn't it be
>>> being freed automatically?
> 
>> Nope, as the module itself will not go away necessarily. I hit
>> the bug when unloading and reloading the machine driver.
>> cs4271_probe(codec) will fail to acquire and drive the reset
>> line, and the codec stays in reset.
> 
> The fix here is to move the resource acquisition to the bus level
> probe instead of the ASoC card startup.
> 

Alright. I thought there was a verdict once that resource claiming
should be done right before usage, but you're right, it really rather
belongs into the bus probe functions.

I'll send another version.

Thanks!
Daniel