From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D5EAC433EF for ; Wed, 4 May 2022 23:33:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231305AbiEDXgC (ORCPT ); Wed, 4 May 2022 19:36:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1380101AbiEDX13 (ORCPT ); Wed, 4 May 2022 19:27:29 -0400 Received: from vps0.lunn.ch (vps0.lunn.ch [185.16.172.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9E5B50B13; Wed, 4 May 2022 16:23:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=z9csiruEF5xbbCJV5LeYL29FmqJAFdz3ZoLv9sjrHrQ=; b=5CK4fQnwZ5a6lvAHhinEALRp/t S43cRzuf6hgQWYVQ1BaliQev7dwRrINVXjS9k+S65XNd2DhoSZjUjVh6M0lYbL2rWbXbKyl4E4ZNw Y/iJ8VeRoPwZISh+iABX3W3HfrLNqZu1Ezh6T+/J3kmh7ySGtSurUk+ZN+Ff/NWcyW/U=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1nmOLI-001HGB-8v; Thu, 05 May 2022 01:23:36 +0200 Date: Thu, 5 May 2022 01:23:36 +0200 From: Andrew Lunn To: Ansuel Smith Cc: Vivien Didelot , Florian Fainelli , Vladimir Oltean , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Jonathan Corbet , Pavel Machek , John Crispin , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-leds@vger.kernel.org Subject: Re: [RFC PATCH v6 02/11] leds: add function to configure hardware controlled LED Message-ID: References: <20220503151633.18760-1-ansuelsmth@gmail.com> <20220503151633.18760-3-ansuelsmth@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220503151633.18760-3-ansuelsmth@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org > +In SUPPORTED hw_control_configure() should return 0 or 1 if the LED driver supports the > +requested blink mode (flags) or not. -EOPNOTSUPP might be clearer. > +In ZERO hw_control_configure() should return 0 with success operation or error. > + > +The unsigned long flag is specific to the trigger and change across them. It's in the LED > +driver interest know how to elaborate this flag and to declare support for a > +particular trigger. For this exact reason explicit support for the specific > +trigger is mandatory or the driver returns -EOPNOTSUPP if asked to enter offload mode > +with a not supported trigger. > +If the driver returns -EOPNOTSUPP on hw_control_configure(), the trigger activation will > +fail as the driver doesn't support that specific offload trigger or doesn't know > +how to handle the provided flags. > + > Known Issues > ============ > > diff --git a/include/linux/leds.h b/include/linux/leds.h > index 09ff1dc6f48d..b5aad67fecfb 100644 > --- a/include/linux/leds.h > +++ b/include/linux/leds.h > @@ -73,6 +73,16 @@ enum led_blink_modes { > SOFTWARE_HARDWARE_CONTROLLED, > }; > > +#ifdef CONFIG_LEDS_HARDWARE_CONTROL > +enum blink_mode_cmd { > + BLINK_MODE_ENABLE, /* Enable the hardware blink mode */ > + BLINK_MODE_DISABLE, /* Disable the hardware blink mode */ > + BLINK_MODE_READ, /* Read the status of the hardware blink mode */ > + BLINK_MODE_SUPPORTED, /* Ask the driver if the hardware blink mode is supported */ > + BLINK_MODE_ZERO, /* Disable any hardware blink active */ > +}; > +#endif Skip the #ifdef. The enum itself takes no space if never used, and it makes the driver simpler if they always exist. > + > struct led_classdev { > const char *name; > unsigned int brightness; > @@ -185,6 +195,17 @@ struct led_classdev { > * the old status but that is not mandatory and also putting it off is accepted. > */ > int (*hw_control_stop)(struct led_classdev *led_cdev); > + /* This will be used to configure the various blink modes LED support in hardware > + * mode. > + * The LED driver require to support the active trigger and will elaborate the > + * unsigned long flag and do the operation based on the provided cmd. > + * Current operation are enable,disable,supported and status. > + * A trigger will use this to enable or disable the asked blink mode, check the > + * status of the blink mode or ask if the blink mode can run in hardware mode. > + */ > + int (*hw_control_configure)(struct led_classdev *led_cdev, > + unsigned long flag, > + enum blink_mode_cmd cmd); > #endif > #endif > > @@ -454,6 +475,24 @@ static inline void *led_get_trigger_data(struct led_classdev *led_cdev) > return led_cdev->trigger_data; > } > > +#ifdef CONFIG_LEDS_HARDWARE_CONTROL > +static inline bool led_trigger_blink_mode_is_supported(struct led_classdev *led_cdev, > + unsigned long flag) > +{ > + int ret; > + > + /* Sanity check: make sure led support hw mode */ > + if (led_cdev->blink_mode == SOFTWARE_CONTROLLED) > + return false; > + > + ret = led_cdev->hw_control_configure(led_cdev, flag, BLINK_MODE_SUPPORTED); > + if (ret > 0) > + return true; > + > + return false; > +} > +#endif Please add a version which returns false when CONFIG_LEDS_HARDWARE_CONTROL is disabled. Does this actually need to be an inline function? Andrew