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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FC49C433DF for ; Thu, 2 Jul 2020 14:47:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F06A206E2 for ; Thu, 2 Jul 2020 14:47:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=megous.com header.i=@megous.com header.b="sBmrw1y3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730178AbgGBOrl (ORCPT ); Thu, 2 Jul 2020 10:47:41 -0400 Received: from vps.xff.cz ([195.181.215.36]:46886 "EHLO vps.xff.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730171AbgGBOri (ORCPT ); Thu, 2 Jul 2020 10:47:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=megous.com; s=mail; t=1593701256; bh=uDf9d/uRJiCtCt1AKubcJLejRj1GRrlsMFGfiGhHhXQ=; h=From:To:Cc:Subject:Date:From; b=sBmrw1y3Ge453s/b6duoEIXe2POYkrOzZJaYL8FeCWY463xCsUurnLS8sONz2cBlT TSBlhuShDIyYHOYS0GSD76SQCtKKzw8SP3rbDuWRBcA2wk1tM0SLTISlAGO3FT7xHi EuL4TmVsgJGT2xKBpvFq6vxbOMZnYfHTTL8Sp7I8= From: Ondrej Jirman To: linux-kernel@vger.kernel.org Cc: Ondrej Jirman , Jacek Anaszewski , Pavel Machek , Dan Murphy , linux-leds@vger.kernel.org (open list:LED SUBSYSTEM) Subject: [PATCH RFC] leds: Add support for per-LED device triggers Date: Thu, 2 Jul 2020 16:47:11 +0200 Message-Id: <20200702144712.1994685-1-megous@megous.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some LED controllers may come with an internal HW triggering mechanism for the LED and an ability to switch between user control of the LED, or the internal control. One such example is AXP20X PMIC, that allows wither for user control of the LED, or for internal control based on the state of the battery charger. Add support for registering per-LED device trigger. Names of private triggers need to be globally unique, but may clash with other private triggers. This is enforced during trigger registration. Developers can register private triggers just like the normal triggers, by setting private_led to a classdev of the LED the trigger is associated with. Signed-off-by: Ondrej Jirman --- drivers/leds/led-triggers.c | 12 +++++++++--- include/linux/leds.h | 3 +++ 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 79e30d2cb7a5..3011e2658404 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -50,7 +50,8 @@ ssize_t led_trigger_write(struct file *filp, struct kobject *kobj, down_read(&triggers_list_lock); list_for_each_entry(trig, &trigger_list, next_trig) { - if (sysfs_streq(buf, trig->name)) { + if (sysfs_streq(buf, trig->name) && + (!trig->private_led || trig->private_led == led_cdev)) { down_write(&led_cdev->trigger_lock); led_trigger_set(led_cdev, trig); up_write(&led_cdev->trigger_lock); @@ -96,6 +97,9 @@ static int led_trigger_format(char *buf, size_t size, bool hit = led_cdev->trigger && !strcmp(led_cdev->trigger->name, trig->name); + if (trig->private_led && trig->private_led != led_cdev) + continue; + len += led_trigger_snprintf(buf + len, size - len, " %s%s%s", hit ? "[" : "", trig->name, hit ? "]" : ""); @@ -243,7 +247,8 @@ void led_trigger_set_default(struct led_classdev *led_cdev) down_read(&triggers_list_lock); down_write(&led_cdev->trigger_lock); list_for_each_entry(trig, &trigger_list, next_trig) { - if (!strcmp(led_cdev->default_trigger, trig->name)) { + if (!strcmp(led_cdev->default_trigger, trig->name) && + (!trig->private_led || trig->private_led == led_cdev)) { led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER; led_trigger_set(led_cdev, trig); break; @@ -280,7 +285,8 @@ int led_trigger_register(struct led_trigger *trig) down_write(&triggers_list_lock); /* Make sure the trigger's name isn't already in use */ list_for_each_entry(_trig, &trigger_list, next_trig) { - if (!strcmp(_trig->name, trig->name)) { + if (!strcmp(_trig->name, trig->name) && + (!_trig->private_led || _trig->private_led == trig->private_led)) { up_write(&triggers_list_lock); return -EEXIST; } diff --git a/include/linux/leds.h b/include/linux/leds.h index 2451962d1ec5..0d7577c752ad 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -345,6 +345,9 @@ struct led_trigger { int (*activate)(struct led_classdev *led_cdev); void (*deactivate)(struct led_classdev *led_cdev); + /* LED-private triggers have the LED device set here. */ + struct led_classdev *private_led; + /* LEDs under control by this trigger (for simple triggers) */ rwlock_t leddev_list_lock; struct list_head led_cdevs; -- 2.27.0