[V1] mfd: Convert pm860x to use regmap api

[Haojian Zhuang]

On Thu, Nov 10, 2011 at 9:02 PM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
> On Thu, Nov 10, 2011 at 07:43:26PM +0800, Jett.Zhou wrote:
>> Convert the register read/write code to use the register map API. We
>> still need some pm860x specific code and locking in place to make sure
>> test page read/write can not be interrupted by other i2c operation based
>> on pm860x chip;
>
> Reviewed-by: Mark Brown <broonie at opensource.wolfsonmicro.com>
>
> I'm assuming that the interruptions come from the fact that there's two
> I2C clients?
>

The patch is still invalid. It can't prevent pm860x i2c operation be
interrupted by other clients.

There're two banks in 88pm8607. One is the normal bank, and the other
one is the test bank. Accessing the test bank need a special I2C
sequence.

Touching to 0xFA address
Touching to 0xFB address
Touching to 0xFF address
Accessing bank register
Touching to 0xFE address
Touching 0xFC address

This sequence can't be interrupted. It means that we can't use
i2c_master_send() to implement touching 0xFA address. Otherwise, other
i2c operation may be inserted into 0xFA and 0xFB operation since the
lock of i2c_adapter is already released.

So you need to fix this issue for accessing test bank first. Then you
can replace i2c read/write implementation with regmap for only normal
bank in 88pm8607.

Thanks
Haojian