From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grygorii Strashko Subject: Re: [PATCH] gpio: omap: make gpio numbering deterministical by using of aliases Date: Wed, 15 Jun 2016 12:56:47 +0300 Message-ID: <5761265F.2050508@ti.com> References: <1465898604-16294-1-git-send-email-u.kleine-koenig@pengutronix.de> <20160615072404.GB26768@pengutronix.de> <20160615082705.GW22406@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from arroyo.ext.ti.com ([198.47.19.12]:57123 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751889AbcFOJ5Z (ORCPT ); Wed, 15 Jun 2016 05:57:25 -0400 In-Reply-To: <20160615082705.GW22406@atomide.com> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: Tony Lindgren , =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= Cc: Linus Walleij , Santosh Shilimkar , Kevin Hilman , Alexandre Courbot , Linux-OMAP , "linux-gpio@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Sascha Hauer On 06/15/2016 11:27 AM, Tony Lindgren wrote: > * Uwe Kleine-K=C3=B6nig [160615 00:2= 7]: >> On Wed, Jun 15, 2016 at 08:56:58AM +0200, Linus Walleij wrote: >>> The way forward is to use the character device and use gpiochip >>> devices with offset indexes and look up GPIOs by name from the >>> character devices. If nothing substantial happens I am merging the >>> final pieces of the GPIO chardev ABI for v4.8 and that is doing all= that >>> sysfs was doing and then some. I just need to change a small thing >>> before sending the final version for review. >> >> Hmm, so /sys/class/gpio was obsoleted before the substitution was re= ady? >> I'd say an overlapping of several kernel versions would be good as w= e >> cannot expect that userspace changes as fast as the kernel. >=20 > Well the /sys/class/gpio is an interface, and we'll have to maintain > it basically forever as we all know. It also works just fine for simp= le > things, so let's make sure it is usable. Having it inconsistent can > cause nasty side effects upgrading kernels. >=20 Wouldn't gpio-line-names be helpful for such cases as mentioned in [1],= [2] But I don't know it these properties were exposed in legacy GPIO sysfs = interface also. [1] http://www.spinics.net/lists/linux-gpio/msg15040.html [2] https://patchwork.ozlabs.org/patch/617713/ =20 --=20 regards, -grygorii -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: grygorii.strashko@ti.com (Grygorii Strashko) Date: Wed, 15 Jun 2016 12:56:47 +0300 Subject: [PATCH] gpio: omap: make gpio numbering deterministical by using of aliases In-Reply-To: <20160615082705.GW22406@atomide.com> References: <1465898604-16294-1-git-send-email-u.kleine-koenig@pengutronix.de> <20160615072404.GB26768@pengutronix.de> <20160615082705.GW22406@atomide.com> Message-ID: <5761265F.2050508@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 06/15/2016 11:27 AM, Tony Lindgren wrote: > * Uwe Kleine-K?nig [160615 00:27]: >> On Wed, Jun 15, 2016 at 08:56:58AM +0200, Linus Walleij wrote: >>> The way forward is to use the character device and use gpiochip >>> devices with offset indexes and look up GPIOs by name from the >>> character devices. If nothing substantial happens I am merging the >>> final pieces of the GPIO chardev ABI for v4.8 and that is doing all that >>> sysfs was doing and then some. I just need to change a small thing >>> before sending the final version for review. >> >> Hmm, so /sys/class/gpio was obsoleted before the substitution was ready? >> I'd say an overlapping of several kernel versions would be good as we >> cannot expect that userspace changes as fast as the kernel. > > Well the /sys/class/gpio is an interface, and we'll have to maintain > it basically forever as we all know. It also works just fine for simple > things, so let's make sure it is usable. Having it inconsistent can > cause nasty side effects upgrading kernels. > Wouldn't gpio-line-names be helpful for such cases as mentioned in [1],[2] But I don't know it these properties were exposed in legacy GPIO sysfs interface also. [1] http://www.spinics.net/lists/linux-gpio/msg15040.html [2] https://patchwork.ozlabs.org/patch/617713/ -- regards, -grygorii