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Subject: Re: [PATCH 4/6] bus: add driver for the Technologic Systems NBUS
To: Linus Walleij <linus.walleij@linaro.org>
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From: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
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Date: Fri, 3 Feb 2017 10:56:34 -0500
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Hi Linus,

On 02/03/2017 08:51 AM, Linus Walleij wrote:
> Your child nodes I guess will be instatiated as devices as well.
> 
> These devices will have the NBUS driver as .parent in their
> struct device I guess. Else the design of this bus is tilted.
> 
> If the NBUS driver use dev_set_drvdata(dev, state_container_cookie)
> the children can use dev_get_drvdata(dev->parent); to get a pointer to
> the same cookie.
> 
> The subdrivers don't even need to know the members of the state
> container as long as you're just passing a pointer to it. It's
> enough if you forward-declare it as a "pointer to some struct":
> 
> struct foo;
> 
> {
>    struct foo *fooptr = dev_get_drvdata(dev->parent);
>    write(fooptr, 0x10);
> 
> etc

Thanks a lot, this is perfect!

Best Regards,
Sebastien.