Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751062AbaKFLW5 (ORCPT ); Thu, 6 Nov 2014 06:22:57 -0500 Received: from mga11.intel.com ([192.55.52.93]:20981 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750789AbaKFLWy (ORCPT ); Thu, 6 Nov 2014 06:22:54 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,325,1413270000"; d="scan'208";a="627588854" Date: Thu, 6 Nov 2014 13:22:44 +0200 From: Mika Westerberg To: Geert Uytterhoeven Cc: "Rafael J. Wysocki" , Alexandre Courbot , Linus Walleij , Bryan Wu , Richard Purdie , Ben Dooks , Kukjin Kim , Jason Cooper , Andrew Lunn , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , ACPI Devel Maling List , Linux-sh list Subject: Re: [PATCH] leds: leds-gpio: Convert gpio_blink_set() to use GPIO descriptors Message-ID: <20141106112244.GM1618@lahna.fi.intel.com> References: <1414755658-96293-1-git-send-email-mika.westerberg@linux.intel.com> <545843B1.3020101@nvidia.com> <2455157.3p7mHhT8im@vostro.rjw.lan> <20141106103033.GK1618@lahna.fi.intel.com> <20141106105855.GL1618@lahna.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 06, 2014 at 12:12:04PM +0100, Geert Uytterhoeven wrote: > Hi Mika, > > On Thu, Nov 6, 2014 at 11:58 AM, Mika Westerberg > wrote: > > On Thu, Nov 06, 2014 at 11:32:19AM +0100, Geert Uytterhoeven wrote: > >> On Thu, Nov 6, 2014 at 11:30 AM, Mika Westerberg > >> wrote: > >> >> "leds: leds-gpio: Add support for GPIO descriptors" broke leds-gpio on > >> >> non-DT platforms for me: > >> >> > >> >> gpiod_direction_output: invalid GPIO > >> >> leds-gpio: probe of leds-gpio failed with error -22 > >> >> > >> >> (desc is NULL in gpiod_direction_output()). > >> >> > >> >> DT shmobile reference/multi-platform are fine. > >> >> > >> >> I noticed the hard way, as I wanted to add some LEDs to a new platform, > >> >> but couldn't get it work. It turned out it also had stopped working on > >> >> r8a7740/armadillo-legacy, so I started bisecting... > >> > > >> > Which board file that is? > >> > > >> > There is a bug that gpio_to_desc() returns NULL instead if ERR_PTR() in > >> > that patch but I wonder why gpio_is_valid() and devm_gpio_request_one() > >> > do not complain about that prior. > >> > >> arch/arm/mach-shmobile/board-armadillo800eva.c > > > > Are you able to put some printks() to the 'if (!template->gpiod)' branch > > so that it prints out gpio number and what does devm_gpio_request_one() > > return? > > > > Something like: > > > > if (!template->gpiod) { > > ... > > ret = devm_gpio_request_one(parent, template->gpio, flags, > > template->name); > > dev_info(parent, "GPIO %u, ret: %d\n", template->gpio, ret); > > if (ret < 0) > > ... > > > > led_dat->gpiod = gpio_to_desc(template->gpio); > > dev_info(parent, "GPIOD: %p\n", led_dat->gpiod); > > Sure: > > leds-gpio leds-gpio: GPIO 102, ret: 0 > leds-gpio leds-gpio: GPIOD: c050e970 > > So led_dat is non-NULL. But it's overwritten by NULL later: > > led_dat->gpiod = template->gpiod; Ah, that's it. Nice catch! > Whitespace damaged fix below, to fold into the original. > If you prefer a proper separate patch, let me know. It is up to Rafael. I think he wants to stabilize this branch so in that case separate patch on top would work better. Feel free to add, Reviewed-by: Mika Westerberg to the patch. > > diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c > index ba4698c32bb04bde..b3c5d9d6a42bcd8b 100644 > --- a/drivers/leds/leds-gpio.c > +++ b/drivers/leds/leds-gpio.c > @@ -92,7 +92,8 @@ static int create_gpio_led(const struct gpio_led *template, > { > int ret, state; > > - if (!template->gpiod) { > + led_dat->gpiod = template->gpiod; > + if (!led_dat->gpiod) { > /* > * This is the legacy code path for platform code that > * still uses GPIO numbers. Ultimately we would like to get > @@ -122,8 +123,7 @@ static int create_gpio_led(const struct gpio_led *template, > > led_dat->cdev.name = template->name; > led_dat->cdev.default_trigger = template->default_trigger; > - led_dat->gpiod = template->gpiod; > - led_dat->can_sleep = gpiod_cansleep(template->gpiod); > + led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod); > led_dat->blinking = 0; > if (blink_set) { > led_dat->platform_gpio_blink_set = blink_set; > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/