Messages in this thread | | | Date | Mon, 13 May 2013 01:36:23 +0200 | Subject | Re: [PATCH] pinctrl: document the "GPIO mode" pitfall | From | Linus Walleij <> |
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On Sat, Apr 27, 2013 at 3:16 AM, Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote: > On Friday 26 April 2013 10:49:12 Linus Walleij wrote:
>> > Does DRIVE_* imply that the pin is driven by the selected function, and >> > OUTPUT imply that the pin is driven to a fixed level ? >> >> That is unclear, but I suggest DRIVE* implies that everything on the pin >> is driven according to that configuration. (Else it is getting ignored...) >> >> OUTPUT would be used when you don't know the particulars or when >> the driving cannot be controlled in a fine-grained manner like with the >> DRIVE* configs. >> >> Does this make sense? > > Kinda, but it's still unclear to me. While the options are (briefly) > documented, how they interact isn't.
Do you think the sematics need to be etched in stone or do you think it could be left as driver-specific, like if I write in the defintion that the interaction of different config arguments is up to the driver?
>> > What about cases where I want to drive the pin to a fixed level in a non >> > low-power output mode (for instance because I need more current that what >> > the low-power output mode provides) ? >> >> Just use pinconfig for that? > > How would you do so ? Only OUTPUT allows setting the output level explictly, > the other DRIVE_* options don't specify the output level.
The PIN_CONFIG_DRIVE_STRENGTH argument is in mA.
Is this what you're after or something else?
Yours, Linus Walleij
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