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From: Danny Huang <dahuang@nvidia.com>
To: Mark Brown <broonie@opensource.wolfsonmicro.com>
CC: "lrg@ti.com" <lrg@ti.com>, "mike@compulab.co.il" <mike@compulab.co.il>,
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Date: Mon, 8 Aug 2011 20:28:30 +0800
Subject: RE: [PATCH] regulator: tps6586x: add SMx slew rate setting
Thread-Topic: [PATCH] regulator: tps6586x: add SMx slew rate setting
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From: Mark Brown, Sent: Monday, August 08, 2011 17:37
> On Fri, Aug 05, 2011 at 07:51:15PM +0800, Danny Huang wrote:
> > Thanks for the feedback.
> > The reason for using driver_data is that I can't find a proper field in
> regulator_init_data for the slew rate setting.
> > I'll do some correction based on the feedback and try to add a new field for
> the slew rate setting.
> 
> No, this is OK - we should really rename the driver_data field, it's
> very misleading.  However:
> 
> > +       return tps6586x_write(parent, reg, setting->slew_rate);
> 
> what happens if the user sets zero for the slew rate (eg, if another
> field is added to the platform data that they want to set)?  Is this a
> sane setting (like the chip default) or might it break something?

Zero is a valid setting for the regulator but not the default setting.
The default setting is 0x07.
This might affect the system stability under some particular condition.
I thought that users should pick a proper setting before init.