Re: [PATCH 1/2] pinctrl: palmas: do not abort pin configuration forBIAS_DEFAULT
From: Stephen Warren
Date: Wed Oct 02 2013 - 12:10:30 EST
On 10/02/2013 04:40 AM, Linus Walleij wrote:
> On Fri, Sep 27, 2013 at 6:06 PM, Stephen Warren <swarren@xxxxxxxxxxxxx> wrote:
>> [Laxman]
>>> Hmm.. When I added the PIN_DEFAULT, I just though that do not update
>>> anything in the register and implemented like that.
>>> There is nothing "default" option in HW.
>>
>> The description of that pinconfig option is:
>>
>>> 7970cb77 (Heiko Stübner 2013-06-06 16:44:25 +0200 43) * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
>>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 44) * on embedded knowledge of the controller hardware, like current mux
>>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 45) * function. The pull direction and possibly strength too will normally
>>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 46) * be decided completely inside the hardware block and not be readable
>>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 47) * from the kernel side.
>>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 48) * If the argument is != 0 pull up/down is enabled, if it is 0, the
>>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 49) * configuration is ignored. The proper way to disable it is to use
>>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 50) * @PIN_CONFIG_BIAS_DISABLE.
>>
>> If the HW doesn't support any concept of a default pull, I think the
>> driver shouldn't support that option; it should return an error if asked
>> to program it.
>
> Yes that's how I remember it and how we specified it.
> Correct Heiko?
>
>> Presumably given this, LinusW shouldn't have actually applied this
>> patch, since presumably it prevents any other driver from accepting
>> PIN_CONFIG_BIAS_DISABLE even in cases where it is appropriate?
>
> There are many patches I shouldn't have applied ...
>
> Anyway I'm not quite following, this patch affected the Palmas
> driver only I think so how can it prevent any other drivers from doing
> the right thing?
Sorry, for some reason I thought this patch was touching core code
rather than the specific driver:-(
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