Re: [PATCH] hwmon: (lm90) Add device tree support

From: Jean Delvare
Date: Fri Feb 01 2013 - 16:58:14 EST


On Fri, 1 Feb 2013 13:36:40 -0800, Guenter Roeck wrote:
> On Fri, Feb 01, 2013 at 01:18:22PM -0800, Vincent Palatin wrote:
> > When the kernel has device tree support, we avoid doing the auto-detection
> > as probing the busses might mess-up sensitive I2C devices or trigger long
> > timeouts on non-functional busses.
> (...)
> As for the detect function, I am not entirely sure if we want or should get
> rid of it just because OF is configured. That may have unintended side effects.
> Either case, I would argue that if we do want to do that, it should be done
> for _all_ I2C devices and not just for the lm90 driver. In other words, it
> should be done in the I2C subsystem, maybe with a separate configuration option.

I can't think of any reason for doing that. Detection only happens on
I2C buses which request it (by setting i2c_adapter.class.) I2C system
bus drivers for OF-based platforms would simply not set any class flag,
so detection won't be triggered on them.

--
Jean Delvare
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