linux-kernel - Re: 4.4: camera and unlock buttons produce tons of interrupts (was Re: N900 sleep mode)

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Message-ID: <20160405205137.GA10196@amd>
Date:	Tue, 5 Apr 2016 22:51:37 +0200
From:	Pavel Machek <pavel@....cz>
To:	Tony Lindgren <tony@...mide.com>
Cc:	pali.rohar@...il.com, sre@...nel.org,
	kernel list <linux-kernel@...r.kernel.org>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
	linux-omap@...r.kernel.org, khilman@...nel.org,
	aaro.koskinen@....fi, ivo.g.dimitrov.75@...il.com,
	patrikbachan@...il.com, serge@...lyn.com
Subject: Re: 4.4: camera and unlock buttons produce tons of interrupts (was
 Re: N900 sleep mode)

Hi!

> > Ok, I realized that _something_ set up my keyboard on console, too, so
> > I'm able to do "init 1" and still interact with the console.
> > 
> > cm_idlest1_core blocking bits are now 0x42 pretty consistently. But
> > they stay 0x42, even when screen is on (and screen on prevents low
> > power, right?) so I guess they are not the whole story.
> 
> Yes they stay at 0x42. And it seems you've configured the UART
> idle timeouts too.

Yes, thanks for the script ;-).

> > I'm able to get down to 50mA power consumption with screen off. I was
> > getting 90mA with X, wifi in powersave and screen off.
> > 
> > Head proximity sensor is still on in this configuration. But I guess
> > that should not keep the system busy...?
> > 
> > Ok, wait a moment, I'm getting "Camera Focus", "Camera Capture" and
> > "Lock button" interrupts ... at something like 20/second. Without
> > touching anything. Hmm. Also "pm_wkup", but that might be
> > expected. Plus, 49052000.gpio and 49054000.gpio are rather
> > active. Might be related to the above. Also "gp_timer" and
> > 48070000.i2c are active, perhaps also related. I don't think I have
> > the camera working...
> 
> Hmm that does not sound right at all for the GPIOs. The pm_wkup
> interrupt triggers every time you hit wfi pretty much, so that
> should be OK.

Wifi was down at that point.

Some more testing: after boot, interrupt counts stay low, as
expected. But when I attempt to enable power management, they start
rising. Sometimes 60/second, sometimes less.

Things are fine as long as I don't enable the off mode; when I enable
the off mode, "echo 1 > /sys/kernel/debug/pm_debug/enable_off_mode"
interrupt counts start rising immediately. "echo 0 >
/sys/kernel/debug/pm_debug/enable_off_mode" stops that.

But no matter what configuration, activity LEDs still indicate it is
busy, and idle power consumption is cca 53mA.

> > "Lock button" interrupt stops increasing as long as I hold the lock
> > button in the "unlock" position. "Camera Focus" and "Camera Capture"
> > will stop increasing when I hold down the Camera button.
> 
> I have not seen that issue last time I checked. Sorry won't
> be able to test it until Thursday, maybe there's some GPIO
> regression now.

No problem, thanks for all the help.

Best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html