[PATCH] add helper for translation of runtime PM errors

[PATCH] add helper for translation of runtime PM errors

[Oliver Neukum]

pm_runtime_get() returns specialised error codes. They are not
fit to be returned to user space. This patch adds a helper
for translation.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
---
 include/linux/pm_runtime.h | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
index 367f49b..67d078f 100644
--- a/include/linux/pm_runtime.h
+++ b/include/linux/pm_runtime.h
@@ -128,6 +128,27 @@ static inline void pm_runtime_mark_last_busy(struct device *dev)
 	ACCESS_ONCE(dev->power.last_busy) = jiffies;
 }
 
+static inline int pm_runtime_translate_errors(int error)
+{
+	int rv;
+
+	switch (error) {
+	case 0:
+	case -ENOMEM:
+	case -EBUSY:
+		rv = error;
+		break;
+	case -EINPROGRESS:
+		rv = -EAGAIN;
+		break;
+	default:
+		rv = error > 0 ? error : -EIO;
+		break;
+	}
+
+	return rv;
+}
+
 #else /* !CONFIG_PM_RUNTIME */
 
 static inline int __pm_runtime_idle(struct device *dev, int rpmflags)
@@ -178,6 +199,10 @@ static inline unsigned long pm_runtime_autosuspend_expiration(
 				struct device *dev) { return 0; }
 static inline void pm_runtime_set_memalloc_noio(struct device *dev,
 						bool enable){}
+static inline int pm_runtime_translate_errors(int error)
+{
+	return error;
+}
 
 #endif /* !CONFIG_PM_RUNTIME */
 
-- 
1.8.4.5

Re: [PATCH] add helper for translation of runtime PM errors

[Alan Stern]

On Thu, 11 Sep 2014, Oliver Neukum wrote:

> pm_runtime_get() returns specialised error codes. They are not
> fit to be returned to user space. This patch adds a helper
> for translation.
> 
> Signed-off-by: Oliver Neukum <oneukum@suse.de>
> ---
>  include/linux/pm_runtime.h | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
> index 367f49b..67d078f 100644
> --- a/include/linux/pm_runtime.h
> +++ b/include/linux/pm_runtime.h
> @@ -128,6 +128,27 @@ static inline void pm_runtime_mark_last_busy(struct device *dev)
>  	ACCESS_ONCE(dev->power.last_busy) = jiffies;
>  }
>  
> +static inline int pm_runtime_translate_errors(int error)
> +{
> +	int rv;
> +
> +	switch (error) {
> +	case 0:
> +	case -ENOMEM:
> +	case -EBUSY:
> +		rv = error;
> +		break;
> +	case -EINPROGRESS:
> +		rv = -EAGAIN;
> +		break;
> +	default:
> +		rv = error > 0 ? error : -EIO;
> +		break;
> +	}
> +
> +	return rv;
> +}

Is this function small enough to be worth inlining?

Alan Stern

Re: [PATCH] add helper for translation of runtime PM errors

[Oliver Neukum]

On Thu, 2014-09-11 at 10:04 -0400, Alan Stern wrote:
> On Thu, 11 Sep 2014, Oliver Neukum wrote:
> 
> > pm_runtime_get() returns specialised error codes. They are not
> > fit to be returned to user space. This patch adds a helper
> > for translation.
> > 
> > Signed-off-by: Oliver Neukum <oneukum@suse.de>
> > ---
> >  include/linux/pm_runtime.h | 25 +++++++++++++++++++++++++
> >  1 file changed, 25 insertions(+)
> > 
> > diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h
> > index 367f49b..67d078f 100644
> > --- a/include/linux/pm_runtime.h
> > +++ b/include/linux/pm_runtime.h
> > @@ -128,6 +128,27 @@ static inline void pm_runtime_mark_last_busy(struct device *dev)
> >  	ACCESS_ONCE(dev->power.last_busy) = jiffies;
> >  }
> >  
> > +static inline int pm_runtime_translate_errors(int error)
> > +{
> > +	int rv;
> > +
> > +	switch (error) {
> > +	case 0:
> > +	case -ENOMEM:
> > +	case -EBUSY:
> > +		rv = error;
> > +		break;
> > +	case -EINPROGRESS:
> > +		rv = -EAGAIN;
> > +		break;
> > +	default:
> > +		rv = error > 0 ? error : -EIO;
> > +		break;
> > +	}
> > +
> > +	return rv;
> > +}
> 
> Is this function small enough to be worth inlining?

I did this because many drivers do

if (ret < 0)
	return ret;

So the compiler can optimize a part away. But yes, I'll test.

	Regards
		Oliver