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In-Reply-To: <20110302113448.GH16181@sortiz-mobl>
References: <1298377440-13032-1-git-send-email-daniel.willerud@stericsson.com>
	<20110302113448.GH16181@sortiz-mobl>
Date: Wed, 2 Mar 2011 15:12:31 +0100
Message-ID: <AANLkTinTP5UKWeu1eGvAA08YKJzz8=iskEPyPVSFzeCM@mail.gmail.com>
Subject: Re: [PATCH] MFD: ab8500: New ab8500_gpadc APIs and reentrance
From: Linus Walleij <linus.walleij@linaro.org>
To: Samuel Ortiz <sameo@linux.intel.com>,
        Daniel Willerud <daniel.willerud@stericsson.com>
Cc: linux-kernel@vger.kernel.org
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2011/3/2 Samuel Ortiz <sameo@linux.intel.com>:

>> +/**
>> + * ab8500_gpadc_get() - returns a reference to the primary AB8500 GPADC
>> + * (i.e. the first GPADC in the instance list)
>> + */
>> +struct ab8500_gpadc *ab8500_gpadc_get(void)
>> +{
>> + ? ? struct ab8500_gpadc *gpadc;
>> + ? ? gpadc = list_first_entry(&ab8500_gpadc_list, struct ab8500_gpadc, node);
>> +
>> + ? ? return gpadc;
>> +}

> This seems really arbitrary. We argued with Mattias about it, and giving
> drivers access to your ADCs means they should somehow have a pointer back to
> the right ADC. That's not the case here, and while it will just work fine
> whenever you have one ADC on your board, you'll probably be relying on some
> sort of device probe order otherwise.

I guess the solution is to rewrite that function to take a parameter
then, such as:

struct ab8500_gpadc *ab8500_gpadc_get(char *name)

If name is then just a strcmpm(dev_name(gpadc->dev), name)
the client use will be something like:

struct ab8500_gpadc *gpadc = ab8500_gpadc_get("ab8500-gpadc.0");

For the first GPDC in the system (unless .init_name is specified
by the ab8500-core when creating the device).

Fair enough?

Yours,
Linus Walleij
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