Re: error returns of pm_runtime_get()

[Oliver Neukum <oneukum@suse.de>]

On Sat, 2014-09-06 at 01:42 +0200, Rafael J. Wysocki wrote:
> On Friday, September 05, 2014 02:43:36 PM Oliver Neukum wrote:
> > 
> > Hi,
> > 
> > looking through multiple drivers it seems to me that a great majority
> > is returning the error returns of pm_runtime_get() to user space.
> > They come quite directly from rpm_resume(). So we are led to return
> > things like -EACCESS or -EINVAL from system calls like open()
> > where they have no place.
> 
> Aren't those driver bugs?

Sure, but almost all drivers using runtime PM are affected.

> > So it seems to me like we should filter more or less like this:
> > 
> > -EBUSY		-> -EBUSY
> > -ENOMEM 	-> -ENOMEM
> > -EINPROGRES	-> -EAGAIN
> > any other error	-> -EIO
> > 
> > And it would be best to retain the current name of pm_runtime_get()
> > and introduce a version with unfiltered error codes.
> > What do you think?
> 
> It doesn't sound right to me.  I may be tired at the moment, but I'm not sure
> what the point would be.

The alternative is to make a conversion helper and to go through all
drivers. Not nice, but if necessary I'll do it.
But we cannot just return things like -EACCESS for internal reasons
while the file permissions are good.

	Regards
		Oliver