From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751501AbdIMRy3 (ORCPT ); Wed, 13 Sep 2017 13:54:29 -0400 Received: from mail-pf0-f182.google.com ([209.85.192.182]:45767 "EHLO mail-pf0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751458AbdIMRyW (ORCPT ); Wed, 13 Sep 2017 13:54:22 -0400 X-Google-Smtp-Source: ADKCNb5CqL74Cu9c7r2t4ajmieLnTlVy2L6qxHl7b+os3IoRw/jhIFzXUA20QXTsunWJ2z/OcZLgew== From: David Lin To: corbet@lwn.net, rpurdie@rpsys.net, jacek.anaszewski@gmail.com, pavel@ucw.cz, hdegoede@redhat.com, gregkh@linuxfoundation.org Cc: robh@kernel.org, romlem@google.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, David Lin Subject: [PATCH v2 3/3] led: ledtrig-transient: add support for hrtimer Date: Wed, 13 Sep 2017 10:54:00 -0700 Message-Id: <20170913175400.42744-4-dtwlin@google.com> X-Mailer: git-send-email 2.14.1.581.gf28d330327-goog In-Reply-To: <20170913175400.42744-1-dtwlin@google.com> References: <20170913175400.42744-1-dtwlin@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds a hrtimer to ledtrig-transient so that when driver is registered with LED_BRIGHTNESS_FAST, the hrtimer is used for the better time accuracy in handling the duration. Signed-off-by: David Lin --- drivers/leds/trigger/ledtrig-transient.c | 59 +++++++++++++++++++++++++++++--- 1 file changed, 54 insertions(+), 5 deletions(-) diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c index 7e6011bd3646..7d2ce757b39d 100644 --- a/drivers/leds/trigger/ledtrig-transient.c +++ b/drivers/leds/trigger/ledtrig-transient.c @@ -24,15 +24,18 @@ #include #include #include +#include #include #include "../leds.h" struct transient_trig_data { + struct led_classdev *led_cdev; int activate; int state; int restore_state; unsigned long duration; struct timer_list timer; + struct hrtimer hrtimer; }; static void transient_timer_function(unsigned long data) @@ -44,6 +47,54 @@ static void transient_timer_function(unsigned long data) led_set_brightness_nosleep(led_cdev, transient_data->restore_state); } +static enum hrtimer_restart transient_hrtimer_function(struct hrtimer *timer) +{ + struct transient_trig_data *transient_data = + container_of(timer, struct transient_trig_data, hrtimer); + + transient_timer_function((unsigned long)transient_data->led_cdev); + + return HRTIMER_NORESTART; +} + +static void transient_timer_setup(struct led_classdev *led_cdev) +{ + struct transient_trig_data *tdata = led_cdev->trigger_data; + + if (led_cdev->flags & LED_BRIGHTNESS_FAST) { + tdata->led_cdev = led_cdev; + hrtimer_init(&tdata->hrtimer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); + tdata->hrtimer.function = transient_hrtimer_function; + } else { + setup_timer(&tdata->timer, transient_timer_function, + (unsigned long)led_cdev); + } +} + +static void transient_timer_start(struct led_classdev *led_cdev) +{ + struct transient_trig_data *tdata = led_cdev->trigger_data; + + if (led_cdev->flags & LED_BRIGHTNESS_FAST) { + hrtimer_start(&tdata->hrtimer, ms_to_ktime(tdata->duration), + HRTIMER_MODE_REL); + } else { + mod_timer(&tdata->timer, + jiffies + msecs_to_jiffies(tdata->duration)); + } +} + +static void transient_timer_cancel(struct led_classdev *led_cdev) +{ + struct transient_trig_data *tdata = led_cdev->trigger_data; + + if (led_cdev->flags & LED_BRIGHTNESS_FAST) + hrtimer_cancel(&tdata->hrtimer); + else + del_timer_sync(&tdata->timer); +} + static ssize_t transient_activate_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -70,7 +121,7 @@ static ssize_t transient_activate_store(struct device *dev, /* cancel the running timer */ if (state == 0 && transient_data->activate == 1) { - del_timer(&transient_data->timer); + transient_timer_cancel(led_cdev); transient_data->activate = state; led_set_brightness_nosleep(led_cdev, transient_data->restore_state); @@ -84,8 +135,7 @@ static ssize_t transient_activate_store(struct device *dev, led_set_brightness_nosleep(led_cdev, transient_data->state); transient_data->restore_state = (transient_data->state == LED_FULL) ? LED_OFF : LED_FULL; - mod_timer(&transient_data->timer, - jiffies + msecs_to_jiffies(transient_data->duration)); + transient_timer_start(led_cdev); } /* state == 0 && transient_data->activate == 0 @@ -182,8 +232,7 @@ static void transient_trig_activate(struct led_classdev *led_cdev) if (rc) goto err_out_state; - setup_timer(&tdata->timer, transient_timer_function, - (unsigned long) led_cdev); + transient_timer_setup(led_cdev); led_cdev->activated = true; return; -- 2.14.1.581.gf28d330327-goog