RE: [PATCH v3 6/8] pwm: rzg2l-gpt: Add suspend/resume support

[Biju Das]

Hi Uwe,

> -----Original Message-----
> From: Uwe Kleine-König <ukleinek@xxxxxxxxxx>
> Sent: 01 December 2025 15:29
> Subject: Re: [PATCH v3 6/8] pwm: rzg2l-gpt: Add suspend/resume support
> 
> Hello Biju,
> 
> On Mon, Dec 01, 2025 at 03:04:08PM +0000, Biju Das wrote:
> > You mean to avoid unbalance between suspend()/resume(), we should not
> > do error handling in resume()??
> 
> Consider the following resume function:
> 
> 	static int myresume(...)
> 	{
> 		ret = enable_some_resource(...);
> 		if (ret)
> 			return ret;
> 
> 		ret = enable_some_other_resource(...)
> 		if (ret) {
> 			disable_some_resource();
> 			return ret;
> 
> 		}
> 
> 		return 0;
> 	}
> 
> If disable_some_resource() can fail it might happen that the first call to myresume() is left with
> some_resource enabled and some_other_resource disabled (i.e. if both enable_some_other_resource() and
> disable_some_resource() fail). Now if the resume is retried some_resource is enabled a second time
> without being tracked and a later suspend (or remove) won't bring the enable count to 0 and thus leak
> a resource.

OK, what about for making balanced usage count for suspend()/resume() to avoid resource 
like below

static int myresume(...)
{
	ret = enable_some_resource(...);
	ret |= enable_some_other_resource(...);

	return ret;
}

static int mysuspend(...)
{
	disable_some_resource(...);
	disable_some_other_resource(...)

	return 0;
}