Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755597AbaJ1Vfj (ORCPT ); Tue, 28 Oct 2014 17:35:39 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:57126 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755260AbaJ1Vfe (ORCPT ); Tue, 28 Oct 2014 17:35:34 -0400 From: "Rafael J. Wysocki" To: Linus Walleij , Mika Westerberg Cc: Linux Kernel Mailing List , Greg Kroah-Hartman , Grant Likely , Arnd Bergmann , ACPI Devel Maling List , Aaron Lu , "devicetree@vger.kernel.org" , Alexandre Courbot , Dmitry Torokhov , Bryan Wu , Darren Hart , Mark Rutland Subject: Re: [PATCH v5 07/12] leds: leds-gpio: Add support for GPIO descriptors Date: Tue, 28 Oct 2014 22:56:09 +0100 Message-ID: <17483842.EFni4iQX1H@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: <2660541.BycO7TFnA2@vostro.rjw.lan> <3395005.IveyhHQnye@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, October 28, 2014 04:26:25 PM Linus Walleij wrote: > On Fri, Oct 17, 2014 at 2:11 PM, Rafael J. Wysocki wrote: > > > From: Mika Westerberg > > > > GPIO descriptors are the preferred way over legacy GPIO numbers > > nowadays. Convert the driver to use GPIO descriptors internally but > > still allow passing legacy GPIO numbers from platform data to support > > existing platforms. > > > > Signed-off-by: Mika Westerberg > > Acked-by: Alexandre Courbot > > Acked-by: Bryan Wu > > Signed-off-by: Rafael J. Wysocki > (...) > > > if (led_dat->blinking) { > > - led_dat->platform_gpio_blink_set(led_dat->gpio, > > - led_dat->new_level, > > - NULL, NULL); > > + int gpio = desc_to_gpio(led_dat->gpiod); > > + int level = led_dat->new_level; > > So this desc_to_gpio() is done only to call the legacy callback below? > > > + if (gpiod_is_active_low(led_dat->gpiod)) > > + level = !level; > > And that leads to making it necessary to have this helper variable > to invert the level since that callback does not pass a descriptor > (which would inherently know if it's active low).... > > > + > > + led_dat->platform_gpio_blink_set(gpio, level, NULL, NULL); > > Is it *really* impossible to change all the users of this callback? You said it could be done in a followup patch. Here: http://marc.info/?l=linux-acpi&m=141154536921643&w=4 And Mika said he would add that to his TODO list: http://marc.info/?l=linux-acpi&m=141155173924101&w=4 I suppose that is still valid. > > > led_dat->blinking = 0; > > } else > > - gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level); > > + gpiod_set_value_cansleep(led_dat->gpiod, led_dat->new_level); > > (...) > > /* Setting GPIOs with I2C/etc requires a task context, and we don't > > * seem to have a reliable way to know if we're already in one; so > > * let's just assume the worst. > > @@ -72,11 +73,16 @@ static void gpio_led_set(struct led_clas > > schedule_work(&led_dat->work); > > } else { > > if (led_dat->blinking) { > > - led_dat->platform_gpio_blink_set(led_dat->gpio, level, > > - NULL, NULL); > > + int gpio = desc_to_gpio(led_dat->gpiod); > > + > > + if (gpiod_is_active_low(led_dat->gpiod)) > > + level = !level; > > + > > + led_dat->platform_gpio_blink_set(gpio, level, NULL, > > + NULL); > > Same comment. > > > @@ -85,9 +91,10 @@ static int gpio_blink_set(struct led_cla > > { > > struct gpio_led_data *led_dat = > > container_of(led_cdev, struct gpio_led_data, cdev); > > + int gpio = desc_to_gpio(led_dat->gpiod); > > > > led_dat->blinking = 1; > > - return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK, > > + return led_dat->platform_gpio_blink_set(gpio, GPIO_LED_BLINK, > > delay_on, delay_off); > > Same comment. > > > @@ -97,24 +104,33 @@ static int create_gpio_led(const struct > > { > > int ret, state; > > > > - led_dat->gpio = -1; > > + if (!template->gpiod) { > > + unsigned long flags = 0; > > > > - /* skip leds that aren't available */ > > - if (!gpio_is_valid(template->gpio)) { > > - dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n", > > - template->gpio, template->name); > > - return 0; > > + /* skip leds that aren't available */ > > + if (!gpio_is_valid(template->gpio)) { > > + dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n", > > + template->gpio, template->name); > > + return 0; > > + } > > + > > + if (template->active_low) > > + flags |= GPIOF_ACTIVE_LOW; > > + > > + ret = devm_gpio_request_one(parent, template->gpio, flags, > > + template->name); > > + if (ret < 0) > > + return ret; > > + > > + led_dat->gpiod = gpio_to_desc(template->gpio); > > + if (IS_ERR(led_dat->gpiod)) > > + return PTR_ERR(led_dat->gpiod); > > } > > OK so this is the legacy codepath: point it out in a big fat > comment that this is the legacy codepath. That looks like it could be done in a followup patch too. Since the series is in my linux-next branch at this point, I really wouldn't like to reshuffle commits in it if that can be avoided. > > Index: linux-pm/include/linux/leds.h > > =================================================================== > > --- linux-pm.orig/include/linux/leds.h > > +++ linux-pm/include/linux/leds.h > > @@ -251,6 +251,7 @@ struct gpio_led { > > unsigned retain_state_suspended : 1; > > unsigned default_state : 2; > > /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ > > + struct gpio_desc *gpiod; > > Put the new struct member right below the current "gpio" > member, It was done like that in previous versions, but turned out to cause problems to happen in testing. Unfortunately, I don't seem to be able to find a pointer to the original report ATM, but perhaps Mika can. Mika? > and add comments saying that either needs to be > specified but "gpio" is deprecated for "gpiod". Kind regards, Rafael -- 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/