[PATCH v3 4/6] pinctrl: Add pinctrl binding for Broadcom Capri SoCs
linus.walleij at linaro.org
Mon Dec 16 08:17:29 EST 2013
On Sat, Dec 14, 2013 at 2:16 AM, Sherman Yin <syin at broadcom.com> wrote:
>>> +- bias-pull-up: Integer. Pull up strength in Ohm:
>>> + 1: 1.2 kOhm
>>> + 2: 1.8 kOhm
>>> + 3: 720 Ohm
>>> + 4: 2.7 kOhm
>>> + 5: 831 Ohm
>>> + 6: 1.08 kOhm
>>> + 7: 568 Ohm
>> Please do not use these custom enumerators 1 thru 7.
>> Instead say that the argument is given in ohms, so for
>> bias-pull-up = <12000>;
>> Then translate this into the proper enumerator in your
>> driver instead.
> Ok. The 3 bits in this enumeration correspond to enabling the 3 pull up Rs
> (1.2k, 1.8k, 2.7k) in parallel, so the enum kind of make sense. But sure I
> can change it to actual ohms and will error out in the driver if specified
> value is not one of the 7.
Aha, that's how they do it :-)
Please write this in a comment in the driver because it makes
it a lot easier to understand what is going on, and e.g. how to
fuzz an apropriate resistance.
Can you tell me something about how such resistors are produced
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