From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932248Ab3FLXJe (ORCPT ); Wed, 12 Jun 2013 19:09:34 -0400 Received: from gloria.sntech.de ([95.129.55.99]:37538 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756837Ab3FLXJd (ORCPT ); Wed, 12 Jun 2013 19:09:33 -0400 From: Heiko =?utf-8?q?St=C3=BCbner?= To: James Hogan Subject: Re: [PATCH 1/2] pinctrl: add function to parse generic pinconfig properties from a dt node Date: Thu, 13 Jun 2013 00:22:29 +0200 User-Agent: KMail/1.13.7 (Linux/3.2.0-3-686-pae; KDE/4.8.4; i686; ; ) Cc: Linus Walleij , Patrice Chotard , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" References: <201306102139.32444.heiko@sntech.de> <201306102140.29918.heiko@sntech.de> <51B88BD0.805@imgtec.com> In-Reply-To: <51B88BD0.805@imgtec.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <201306130022.29341.heiko@sntech.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi James, Am Mittwoch, 12. Juni 2013, 16:55:12 schrieb James Hogan: > Hi Heiko, > > On 10/06/13 20:40, Heiko Stübner wrote: > > pinconf_generic_parse_dt_config() takes a node as input and generates an > > array of generic pinconfig values from the properties of this node. > > > > As I couldn't find a mechanism to count the number of properties of a > > node the function uses internally an array to accept one of parameter > > and copies the real present options to a smaller variable at its end. > > > > Signed-off-by: Heiko Stuebner > > > > > @@ -139,3 +140,83 @@ void pinconf_generic_dump_config(struct pinctrl_dev > > *pctldev, > > > > } > > EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); > > #endif > > > > + > > +#ifdef CONFIG_OF > > +struct pinconf_generic_dt_params { > > + const char * const property; > > + enum pin_config_param param; > > + u32 default_value; > > +}; > > + > > +static struct pinconf_generic_dt_params dt_params[] = { > > + { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, > > + { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, > > + { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, > > + { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 0 }, > > + { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 0 }, > > + { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 0 }, > > + { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, > > + { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, > > + { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, > > + { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, > > + { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, > > + { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, > > + { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, > > + { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, > > + { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, > > + { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, > > + { "low-power-mode", PIN_CONFIG_LOW_POWER_MODE, 0 }, > > + { "output-low", PIN_CONFIG_OUTPUT, 0, }, > > + { "output-high", PIN_CONFIG_OUTPUT, 1, }, > > shouldn't half of these default to 1 instead of 0? i.e. it's much nicer > for the lone flag "bias-pull-up" to enable pull up rather than disable > it (you even do this in the DT example in the bindings doc). on closer inspection it seems that you may be right. The documentation to the options in the pinconf-generic header even tells that for example the pull options do have a 0 or 1 argument. I guess I got much inspiration from sh-pfc/pinctrl.c when learning about the generic pinconf, which ignores any argument for these options, which I then have mimiced in my rockchip driver and here. But I'm not sure if I understand everything correctly :-) ... isn't the bias- disable the opposite of turning on a pull (like the sh-pfc/pinctrl does) and same with switching from one pull type to another, i.e. activating a pull up would turn off a pull down and on the whole making the argument redundant? The only other candidate I could find was low-power-mode which really could use a "1" as default. All the other pinconf options either use custom arguments or ignore teir argument. > Otherwise the patch looks good to me (though I haven't tried it yet). nice Heiko