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Date: Fri, 21 Nov 2014 14:09:40 -0800
From: Darren Hart <dvhart@infradead.org>
To: Pali =?iso-8859-1?Q?Roh=E1r?= <pali.rohar@gmail.com>
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Subject: Re: [PATCH] platform: x86: dell-laptop: Add support for keyboard
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On Sat, Nov 22, 2014 at 07:46:25PM +0100, Pali Rohár wrote:

> > > 0   Completed successfully
> > > -1  Completed with error
> > > -2  Function not supported
> > > 
> > > So we can return something other too (not always -EINVAL).
> > > Do you have any idea which errno should we return for -1
> > > and -2?
> > 
> > For -1, I should think  -EIO (I/O Error)
> > For -2, I'd expect -ENXIO (No such device or address)
> > 
> 
> What about -ENOSYS for -2?

No. This specific topic came up at kernel summit this year. ENOSYS is
specifically for not implemented system calls.

> 
> > > > > +	if (convert) {
> > > > > +		/* NOTE: this switch fall down */
> > > > 
> > > > "fall down" ? As in, it intentionally doesn't have breaks?
> > > 
> > > This code convert "value" in "units" to new value in minutes
> > > units. So for unit == days it is: 24*60*60... So no breaks.
> > 
> > Right, so the language of the comment just wasn't clear, try:
> > 
> > /* Convert value from seconds to minutes */
> > 
> 
> Err... to seconds :-) But OK, I will change comment.

Oops, duh.

/* Convert value from current units to seconds. */

> 
> > > > > +		switch (unit) {
> > > > > +		case KBD_TIMEOUT_DAYS:
> > > > > +			value *= 24;
> > > > > +		case KBD_TIMEOUT_HOURS:
> > > > > +			value *= 60;
> > > > > +		case KBD_TIMEOUT_MINUTES:
> > > > > +			value *= 60;
> > > > > +			unit = KBD_TIMEOUT_SECONDS;
> > > > > +	 	}

-- 
Darren Hart
Intel Open Source Technology Center