linux-kernel - Re: mc13xxx-core: kernel hangs after 'regmap

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Date:	Wed, 23 May 2012 16:32:37 -0300
From:	Fabio Estevam <festevam@...il.com>
To:	Mark Brown <broonie@...nsource.wolfsonmicro.com>
Cc:	marc@...esign.com.au, Samuel Ortiz <sameo@...ux.intel.com>,
	Sascha Hauer <kernel@...gutronix.de>,
	Philippe Rétornaz <philippe.retornaz@...l.ch>,
	linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: mc13xxx-core: kernel hangs after 'regmap_read'

On Wed, May 23, 2012 at 2:36 PM, Mark Brown
<broonie@...nsource.wolfsonmicro.com> wrote:

> The data sent should be however many bits of register address are
> specified, followed by however many padding bits are specified, followed
> by the data.  The shift there will be some combination of the padding
> and register address.

Ok, from the mc13783 datasheet:

"Both SPI ports are configured to utilize 32-bit serial data words,
using 1 read/write bit, 6 address bits, 1
null bit, and 24 data bits. The SPI ports’ 64 registers correspond to
the 6 address bits."

,and we have the struct regmap_config as:

	.reg_bits = 7,
	.pad_bits = 1,
	.val_bits = 24,

>From the bootloader I read PMIC register 0 as 0x00081000.

In the kernel all the PMIC registers accesses are read as: 0x00000810

So it looks when I read a register via SPI through regmap the register
address field is not being updated correctly (like as it was always
reading from register 0) and there is also a shift by 8 in there.
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