linux-kernel - Re: [PATCH v4 4/5] dell-wmi: properly process Dell Instant Launch hotkey

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Date:	Mon, 29 Feb 2016 15:00:15 -0800
From:	Darren Hart <dvhart@...radead.org>
To:	Pali Rohár <pali.rohar@...il.com>
Cc:	Michał Kępień <kernel@...pniu.pl>,
	Matthew Garrett <mjg59@...f.ucam.org>,
	Darek Stojaczyk <darek.stojaczyk@...il.com>,
	platform-driver-x86@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 4/5] dell-wmi: properly process Dell Instant Launch
 hotkey

On Mon, Feb 29, 2016 at 09:56:03PM +0100, Pali Rohár wrote:
> On Monday 29 February 2016 21:49:27 you wrote:
> > > On Monday 29 February 2016 21:31:23 Michał Kępień wrote:
> > > > > > diff --git a/drivers/platform/x86/dell-wmi.c
> > > > > > b/drivers/platform/x86/dell-wmi.c index 65edd93..ffc957b5
> > > > > > 100644 --- a/drivers/platform/x86/dell-wmi.c
> > > > > > +++ b/drivers/platform/x86/dell-wmi.c
> > > > > > @@ -111,7 +111,7 @@ static const struct key_entry
> > > > > > dell_wmi_legacy_keymap[] __initconst = {
> > > > > > 
> > > > > >  	{ KE_IGNORE, 0xe020, { KEY_MUTE } },
> > > > > >  	
> > > > > >  	/* Shortcut and audio panel keys */
> > > > > > 
> > > > > > -	{ KE_IGNORE, 0xe025, { KEY_RESERVED } },
> > > > > > +	{ KE_KEY, 0xe025, { KEY_PROG4 } },
> > > > > > 
> > > > > >  	{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
> > > > > >  	
> > > > > >  	{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
> > > > > > 
> > > > > > @@ -235,6 +235,9 @@ static void dell_wmi_process_key(int
> > > > > > reported_key)
> > > > > > 
> > > > > >  	    acpi_video_handles_brightness_key_presses())
> > > > > >  		
> > > > > >  		return;
> > > > > > 
> > > > > > +	if (key->keycode == KEY_PROG4 &&
> > > > > > !wmi_requires_smbios_request) +		return;
> > > > > > +
> > > > > 
> > > > > Here I would rather test against reported_key, not keycode. If
> > > > > somebody in future adds KEY_PROG4 for something else we will
> > > > > have problem...
> > > > 
> > > > As 0xe025 is currently the only event we know about that should
> > > > be ignored on some machines and processed on others, this makes
> > > > sense,
> > > > 
> > > > at least for now.  If I change the first condition to:
> > > >     reported_key == 0xe025
> > > 
> > > There will be need also change for 5/5 patch...
> > 
> > Why?  Are you aware of any model which sends a 0xe029 WMI event _and_
> > generates an i8042 interrupt?  If not, WMI event 0xe029 should always
> > be turned into a key event, as per the keymap.
> 
> No, but your current patch 4/5 and 5/5 do that (because it checks 
> KEY_PROG4). But if it is not needed, I'm happy because of one hook less.

>From my reading, patch 5/5 adds 0xe029 to the reported keys that need to be
ignored, so the test would need to include both if it isn't using the common
keycode KEY_PROG4. I believe that is what Pali is saying as well. Is this not
the correct reading of 5/5?

> 
> -- 
> Pali Rohár
> pali.rohar@...il.com



-- 
Darren Hart
Intel Open Source Technology Center