Re: [PATCH 1/2] AB3100 regulator support v2

[Mark Brown <broonie@opensource.wolfsonmicro.com>]

On Wed, Sep 02, 2009 at 12:05:10AM +0200, Linus Walleij wrote:

> But generally speaking the AB3100 can be used on top of any
> i2c adapter and a bunch of them actually use
> wait_for_completion_interruptible_timeout();
> and wait_event_interruptible_timeout(); for example.

There was some discussion of this on the I2C list and a decision that it
was sensible to move away from doing that since it was being found to
cause more problems than it solved - the FSL driver is the one I
remember actually doing so.

> One of them being i2c/buses/i2c-imx.c actually, Mark does
> this mean you actually have the risk of being kill -9:ed in the
> middle of a regulator operation for the WM drivers, for
> example

Yes.  Pretty much any embedded I2C driver could cause issues for the
Wolfson drivers - there's a whole bunch of audio CODECs that are very
widely deployed.

> In the general sense perhaps this doesn't happen so much,

Yes, it's fairly rare which is the main reason it's not being chased
after particularly actively.