Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751352AbaKFLMM (ORCPT ); Thu, 6 Nov 2014 06:12:12 -0500 Received: from mail-lb0-f178.google.com ([209.85.217.178]:60982 "EHLO mail-lb0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062AbaKFLMH (ORCPT ); Thu, 6 Nov 2014 06:12:07 -0500 MIME-Version: 1.0 In-Reply-To: <20141106105855.GL1618@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> Date: Thu, 6 Nov 2014 12:12:04 +0100 X-Google-Sender-Auth: m-TVktPzet2fHM7xLyN16f36OF8 Message-ID: Subject: Re: [PATCH] leds: leds-gpio: Convert gpio_blink_set() to use GPIO descriptors From: Geert Uytterhoeven To: Mika Westerberg 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 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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; Whitespace damaged fix below, to fold into the original. If you prefer a proper separate patch, let me know. 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/