From patchwork Tue Sep 10 13:27:31 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Jacques Hiblot X-Patchwork-Id: 11139519 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4EC3A14E5 for ; Tue, 10 Sep 2019 13:27:49 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 31F15208E4 for ; Tue, 10 Sep 2019 13:27:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 31F15208E4 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 23B0E6E0B7; Tue, 10 Sep 2019 13:27:45 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from fllv0016.ext.ti.com (fllv0016.ext.ti.com [198.47.19.142]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3A6766E0A5 for ; Tue, 10 Sep 2019 13:27:43 +0000 (UTC) Received: from fllv0035.itg.ti.com ([10.64.41.0]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id x8ADRcdW074556; Tue, 10 Sep 2019 08:27:38 -0500 Received: from DFLE112.ent.ti.com (dfle112.ent.ti.com [10.64.6.33]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTP id x8ADRcer080158; Tue, 10 Sep 2019 08:27:38 -0500 Received: from DFLE113.ent.ti.com (10.64.6.34) by DFLE112.ent.ti.com (10.64.6.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Tue, 10 Sep 2019 08:27:38 -0500 Received: from lelv0326.itg.ti.com (10.180.67.84) by DFLE113.ent.ti.com (10.64.6.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Tue, 10 Sep 2019 08:27:37 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id x8ADRbfE035367; Tue, 10 Sep 2019 08:27:37 -0500 From: Jean-Jacques Hiblot To: , , , , , Subject: [PATCH v6 1/4] leds: Add of_led_get() and led_put() Date: Tue, 10 Sep 2019 15:27:31 +0200 Message-ID: <20190910132734.9544-2-jjhiblot@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190910132734.9544-1-jjhiblot@ti.com> References: <20190910132734.9544-1-jjhiblot@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1568122058; bh=88mpiURaZ0Bg8Ua0PPuNeiQeaqUqbzMHmmZqerjgVIE=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=V5e2Nbz9ulWefAKKyrmMfNZnf4PbnuwtTtuLj71hBjlbYGW755kipGLjKRAimeJIr Mg9CbMOVDbMYUAXys3CIhtA8iVeTmo9yHRjFCAbpipZyVAkC5OCXBO0qfGW7e/yjVC 1w8TS0AufUYnRm2izLPoO1WDeMkvR4rM31Iapl/A= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, tomi.valkeinen@ti.com, dmurphy@ti.com, Jean-Jacques Hiblot , linux-leds@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Tomi Valkeinen This patch adds basic support for a kernel driver to get a LED device. This will be used by the led-backlight driver. Only OF version is implemented for now, and the behavior is similar to PWM's of_pwm_get() and pwm_put(). Signed-off-by: Tomi Valkeinen Signed-off-by: Jean-Jacques Hiblot Acked-by: Pavel Machek --- drivers/leds/led-class.c | 50 ++++++++++++++++++++++++++++++++++++++++ include/linux/leds.h | 4 ++++ 2 files changed, 54 insertions(+) diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 159c6caa374b..d4d22f4b5052 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -18,6 +18,7 @@ #include #include #include +#include #include "leds.h" static struct class *leds_class; @@ -213,6 +214,55 @@ static int led_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); +static int led_match_led_node(struct device *led_dev, const void *data) +{ + return led_dev->of_node == data; +} + +/** + * of_led_get() - request a LED device via the LED framework + * @np: device node to get the LED device from + * @index: the index of the LED + * + * Returns the LED device parsed from the phandle specified in the "leds" + * property of a device tree node or a negative error-code on failure. + */ +struct led_classdev *of_led_get(struct device_node *np, int index) +{ + struct device *led_dev; + struct led_classdev *led_cdev; + struct device_node *led_node; + + led_node = of_parse_phandle(np, "leds", index); + if (!led_node) + return ERR_PTR(-ENOENT); + + led_dev = class_find_device(leds_class, NULL, led_node, + led_match_led_node); + of_node_put(led_node); + + if (!led_dev) + return ERR_PTR(-EPROBE_DEFER); + + led_cdev = dev_get_drvdata(led_dev); + + if (!try_module_get(led_cdev->dev->parent->driver->owner)) + return ERR_PTR(-ENODEV); + + return led_cdev; +} +EXPORT_SYMBOL_GPL(of_led_get); + +/** + * led_put() - release a LED device + * @led_cdev: LED device + */ +void led_put(struct led_classdev *led_cdev) +{ + module_put(led_cdev->dev->parent->driver->owner); +} +EXPORT_SYMBOL_GPL(led_put); + static int match_name(struct device *dev, const void *data) { if (!dev_name(dev)) diff --git a/include/linux/leds.h b/include/linux/leds.h index bee8e3f8dddd..0a71c7cdd191 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -19,6 +19,7 @@ struct device; struct led_pattern; +struct device_node; /* * LED Core */ @@ -145,6 +146,9 @@ extern void devm_led_classdev_unregister(struct device *parent, extern void led_classdev_suspend(struct led_classdev *led_cdev); extern void led_classdev_resume(struct led_classdev *led_cdev); +extern struct led_classdev *of_led_get(struct device_node *np, int index); +extern void led_put(struct led_classdev *led_cdev); + /** * led_blink_set - set blinking with software fallback * @led_cdev: the LED to start blinking