From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754854Ab2IOQVN (ORCPT ); Sat, 15 Sep 2012 12:21:13 -0400 Received: from mail-we0-f174.google.com ([74.125.82.174]:56935 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753126Ab2IOQVL (ORCPT ); Sat, 15 Sep 2012 12:21:11 -0400 From: Fabio Baltieri To: linux-leds@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Richard Purdie , Fabio Baltieri , Kurt Van Dijck , Bryan Wu Subject: [PATCH v2] leds: add led_trigger_rename function Date: Sat, 15 Sep 2012 18:18:44 +0200 Message-Id: <1347725924-1760-1-git-send-email-fabio.baltieri@gmail.com> X-Mailer: git-send-email 1.7.10.3 In-Reply-To: <20120915161518.GA1687@gmail.com> References: <20120915161518.GA1687@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implements a "led_trigger_rename" function to rename a trigger with proper locking. This assumes that led name was originally allocated in non-constant storage. Signed-off-by: Fabio Baltieri Cc: Kurt Van Dijck Cc: Bryan Wu --- drivers/leds/led-triggers.c | 13 +++++++++++++ include/linux/leds.h | 18 ++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index b53bf54..c0f5d7c 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -153,6 +153,19 @@ void led_trigger_set_default(struct led_classdev *led_cdev) } EXPORT_SYMBOL_GPL(led_trigger_set_default); +void led_trigger_rename_static(const char *name, struct led_trigger *trig) +{ + /* new name must be on a temporary string to prevent races */ + BUG_ON(name == trig->name); + + down_write(&triggers_list_lock); + /* this assumes that trig->name was originaly allocated to + * non constant storage */ + strcpy((char *)trig->name, name); + up_write(&triggers_list_lock); +} +EXPORT_SYMBOL_GPL(led_trigger_rename_static); + /* LED Trigger Interface */ int led_trigger_register(struct led_trigger *trig) diff --git a/include/linux/leds.h b/include/linux/leds.h index 5676197..21644c7 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -139,6 +139,24 @@ extern void led_blink_set_oneshot(struct led_classdev *led_cdev, extern void led_set_brightness(struct led_classdev *led_cdev, enum led_brightness brightness); +/** + * led_trigger_rename_static - rename a trigger + * @name: the new trigger name + * @trig: the LED trigger to rename + * + * Change a LED trigger name by copying the string passed in + * name into current trigger name, which MUST be large + * enough for the new string. + * + * Note that name must NOT point to the same string used + * during LED registration, as that could lead to races. + * + * This is meant to be used on triggers with statically + * allocated name. + */ +extern void led_trigger_rename_static(const char *name, + struct led_trigger *trig); + /* * LED Triggers */ -- 1.7.11.rc1.9.gf623ca1.dirty