[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <56EA6326.4000702@gmail.com>
Date: Thu, 17 Mar 2016 09:56:22 +0200
From: Ivaylo Dimitrov <ivo.g.dimitrov.75@...il.com>
To: Sebastian Reichel <sre@...nel.org>
Cc: Grygorii Strashko <grygorii.strashko@...com>,
Pali Rohár <pali.rohar@...il.com>,
Peter Ujfalusi <peter.ujfalusi@...com>,
Jarkko Nikula <jarkko.nikula@...mer.com>,
Tony Lindgren <tony@...mide.com>,
Lars-Peter Clausen <lars@...afoo.de>,
linux-kernel@...r.kernel.org, linux-omap@...r.kernel.org,
Pavel Machek <pavel@....cz>,
Aaro Koskinen <aaro.koskinen@....fi>,
Nishanth Menon <nm@...com>, merlijn@...zup.org
Subject: Re: Nokia N900 - audio TPA6130A2 problems
Hi,
On 17.03.2016 02:49, Sebastian Reichel wrote:
>
> mh both, the power gpio is turned off in tpa6130a2_power(0). I guess
> if you don't see the problem during probe() everything works?
>
> I have another idea though: In opposit to the gpio, the regulator
> may also be referenced by something else/already enabled. I guess
> adding a sleep after the regulator_enable() is worth a try.
>
> Also I wonder if the same happens, if you avoid having the module
> available during boot and instead load it once everything has
> settled. That would rule out any side-effects of other modules
> being probed on the same i2c bus.
Well, I think I've figured it out - input pullups are not enabled
on i2c bus pins, in stock kernel we have:
./devmem2 0x480021BC
Value at address 0x480021BC (0x4001f1bc): 0x1180118
./devmem2 0x480021C0
Value at address 0x480021C0 (0x4001f1c0): 0x1180118
in mainline
./devmem2 0x480021BC
Value at address 0x480021BC (0xb6ff01bc): 0x1000100
./devmem2 0x480021C0
Value at address 0x480021C0 (0xb6f6d1c0): 0x1000100
I wonder how i2c devices work at all :)
Will fix the board DTS file later on an will report
Regards,
Ivo
Powered by blists - more mailing lists