public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Marc Reilly <marc@cpdesign.com.au>
To: Fabio Estevam <festevam@gmail.com>
Cc: "Mark Brown" <broonie@opensource.wolfsonmicro.com>,
	"Samuel Ortiz" <sameo@linux.intel.com>,
	"Sascha Hauer" <kernel@pengutronix.de>,
	"Philippe Rétornaz" <philippe.retornaz@epfl.ch>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: mc13xxx-core: kernel hangs after 'regmap_read'
Date: Tue, 22 May 2012 10:53:21 +1000	[thread overview]
Message-ID: <201205221053.21792.marc@cpdesign.com.au> (raw)
In-Reply-To: <CAOMZO5A-05jTYpEEPfnJvWpby1YJ1M7=KPn=zahbQrQOgbjR4g@mail.gmail.com>

Hi Fabio,

On Tuesday, May 22, 2012 02:06:55 AM Fabio Estevam wrote:
> Hi Marc,
> 
> I am running linux-next 3.4.0-next-20120521 on a mx31pdk board that
> has a mc13783 PMIC connected to SPI.
> 
> I am getting a kernel hang after 'regmap_read' inside mc13xxx_reg_read
> function.
> 
> Does it work fine for you on your mx35 board? Am I missing any recent
> patch?

I tested linux-next/next-20120521, no extra patches. I got build errors for 
something to do with usb udc, and start-up panic for the nand driver. 
Disabling both of these got me to a login. Then:

mount -t debugfs none /sys/kernel/debug
cat /sys/kernel/debug/regmap/0-0008/registers

00: 004cc0
01: ffffff
02: 185cc0
03: 000005
04: ffffff
05: 00401c
06: 000200
07: 0045d0
08: 000000
09: 000005
0a: 00147a
0b: 000000
0c: 000000
0d: 0b0040
0e: 000000
0f: 400032
10: 000000
11: 000000
12: 000001
13: 000000
14: 013326
15: 01ffff
...

Which looks correct.


> 
> My understanding is that you have only tested i2c connection with this
> PMIC. Is this correct?
That's correct. I don't have any SPI connected hardware to test with. Shawn 
tested SPI operation for an earlier version of the patch series, but that was 
before the regmap changes.


> Any ideas on how to solve this issue is appreciated.
My first suspicion is with the regmap register format of the mc13xxx for SPI. 
It was a new format which introduced a padding bit. I wonder if Mark Brown can 
comment on whether any other devices are using it successfully. (Sorry I can't 
offer more insights there).

Does your crash occur during mc13xxx_spi_probe? does mc13xxx_common_init() get 
called?


Cheers,
Marc


  reply	other threads:[~2012-05-22  0:56 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-21 16:06 mc13xxx-core: kernel hangs after 'regmap_read' Fabio Estevam
2012-05-22  0:53 ` Marc Reilly [this message]
2012-05-22  9:25   ` Mark Brown
2012-05-22 11:40     ` Fabio Estevam
2012-05-22 12:48       ` Philippe Rétornaz
2012-05-22 14:45     ` Fabio Estevam
2012-05-23  1:12   ` Fabio Estevam
2012-05-23  2:05     ` Fabio Estevam
2012-05-23  8:49       ` Mark Brown
2012-05-23 14:18         ` Fabio Estevam
2012-05-23 15:29           ` Fabio Estevam
2012-05-23 17:36           ` Mark Brown
2012-05-23 19:32             ` Fabio Estevam
2012-05-23 16:42         ` Shawn Guo
2012-05-23 16:34           ` Fabio Estevam
2012-05-24  0:48             ` Shawn Guo
2012-05-24  4:07               ` Fabio Estevam
2012-05-24  6:04                 ` Shawn Guo
2012-05-24  6:39                 ` Shawn Guo
2012-05-24  6:46                   ` Uwe Kleine-König
2012-05-24  7:33                     ` Shawn Guo
2012-05-24  9:08                       ` Marc Reilly
2012-05-24 10:37                         ` Mark Brown
2012-05-24 11:22                           ` Marc Reilly
2012-05-24 12:14                             ` Mark Brown
2012-05-24 13:06                               ` Marc Reilly
2012-05-24 16:37                                 ` Mark Brown
2012-05-24 13:01                         ` Fabio Estevam
2012-05-24 13:38                           ` Marc Reilly
2012-05-24 16:16                             ` Philippe Rétornaz
2012-05-24 16:36                               ` Mark Brown
2012-05-24 16:41                                 ` Uwe Kleine-König
2012-05-24 17:39                                   ` Fabio Estevam
2012-05-24 18:03                                     ` Mark Brown
2012-05-24 19:42                                       ` philippe.retornaz
2012-05-24 22:21                                         ` Mark Brown
2012-05-25  8:56                         ` Shawn Guo

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=201205221053.21792.marc@cpdesign.com.au \
    --to=marc@cpdesign.com.au \
    --cc=broonie@opensource.wolfsonmicro.com \
    --cc=festevam@gmail.com \
    --cc=kernel@pengutronix.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=philippe.retornaz@epfl.ch \
    --cc=sameo@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox