From mboxrd@z Thu Jan 1 00:00:00 1970 From: 21cnbao@gmail.com (Barry Song) Date: Wed, 14 Sep 2011 09:48:16 +0800 Subject: [PATCH 2/4 v6] pinmux: add a driver for the U300 pinmux In-Reply-To: References: <1314869552-5531-1-git-send-email-linus.walleij@stericsson.com> <74CDBE0F657A3D45AFBB94109FB122FF04B327A40C@HQMAIL01.nvidia.com> <74CDBE0F657A3D45AFBB94109FB122FF04B327A570@HQMAIL01.nvidia.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 2011/9/13 Linus Walleij : > On Fri, Sep 2, 2011 at 6:04 PM, Stephen Warren wrote: >> Linus Walleij wrote at Friday, September 02, 2011 2:12 AM: >>> On Thu, Sep 1, 2011 at 11:33 PM, Stephen Warren wrote: >>> >>> >> +static const struct u300_pmx_func u300_pmx_functions[] = { >>> >> + ? ? { >>> >> + ? ? ? ? ? ? .name = "power", >>> >> + ? ? ? ? ? ? .groups = { POWERGRP_INDEX }, >>> >> + ? ? ? ? ? ? /* Mask is N/A */ >>> >> + ? ? }, >>> > >>> > Hmmm. That's a lot of _INDEX defines that'd need to be set up, at least >>> > to fully represent a chip like Tegra. Can the pinmux core be modified >>> > such that the group list is an array of names (char*) rather than the >>> > actual numeric IDs of the groups? Still, perhaps we could use the enum >>> > we already have for this, so perhaps it isn't a big deal... >>> >>> Well I could think about a lot of ways to do this, but it's basically up >>> to the driver, the U300 is just some simple example of what you can >>> do, it's just trying to satisfy the API. >>> >>> Maybe as part of writing the nVidia driver you find a clever >>> mechanism for doing this, if it's looking generally useful at that >>> point then let's move it to the core I'd say. >> >> The reason I asked about the pinmux core handling this is because the >> driver op get_function_groups: >> >> + ? ? ? int (*get_function_groups) (struct pinctrl_dev *pctldev, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned selector, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned ** const groups, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned * const num_groups); >> >> returns an array of integer indexes. I think the only way to get rid of >> the index definitions in the drivers is to allow get_function_groups to >> return an array of strings instead. > > OK good idea, I reworked this interface to get an array of strings > instead, I've been told several times to use strings rather than numbers > when possible, so I think this is the right thing to do. > > Check it out in v7! well. we'll rebase prima2 pinmux on v7. > > Yours, > Linus Walleij > -barry