Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757981Ab2FGM7O (ORCPT ); Thu, 7 Jun 2012 08:59:14 -0400 Received: from mail-gh0-f174.google.com ([209.85.160.174]:43564 "EHLO mail-gh0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751800Ab2FGM7M convert rfc822-to-8bit (ORCPT ); Thu, 7 Jun 2012 08:59:12 -0400 MIME-Version: 1.0 In-Reply-To: <1339020665-9652-1-git-send-email-fabio.baltieri@gmail.com> References: <1339020665-9652-1-git-send-email-fabio.baltieri@gmail.com> From: Bryan Wu Date: Thu, 7 Jun 2012 20:58:50 +0800 X-Google-Sender-Auth: pKq5KjbPQ1EikVjkVSlIYtEjyX8 Message-ID: Subject: Re: [PATCH v3] led: add oneshot trigger To: Fabio Baltieri Cc: linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org, Richard Purdie , Shuah Khan Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 12497 Lines: 362 On Thu, Jun 7, 2012 at 6:11 AM, Fabio Baltieri wrote: > Add oneshot trigger to blink a led with configurale parameters via > sysfs. > > Signed-off-by: Fabio Baltieri > Cc: Shuah Khan > Cc: Bryan Wu > --- > > Here is the v3, with added documentation file with short description, sysfs > description, use case example (the one I developed ths for, actually) and > default values. > > Also, while trying the use case, I added instantaneous setting of led state when > setting the "invert" attribute. > > Let me know what you think of this! > I'm fine this patch now, and added to my for-next and devel branches. -Bryan > Fabio > > ?Documentation/leds/ledtrig-oneshot.txt | ?59 ++++++++++ > ?drivers/leds/Kconfig ? ? ? ? ? ? ? ? ? | ?14 +++ > ?drivers/leds/Makefile ? ? ? ? ? ? ? ? ?| ? 1 + > ?drivers/leds/ledtrig-oneshot.c ? ? ? ? | 204 +++++++++++++++++++++++++++++++++ > ?4 files changed, 278 insertions(+) > ?create mode 100644 Documentation/leds/ledtrig-oneshot.txt > ?create mode 100644 drivers/leds/ledtrig-oneshot.c > > diff --git a/Documentation/leds/ledtrig-oneshot.txt b/Documentation/leds/ledtrig-oneshot.txt > new file mode 100644 > index 0000000..07cd1fa > --- /dev/null > +++ b/Documentation/leds/ledtrig-oneshot.txt > @@ -0,0 +1,59 @@ > +One-shot LED Trigger > +==================== > + > +This is a LED trigger useful for signaling the user of an event where there are > +no clear trap points to put standard led-on and led-off settings. ?Using this > +trigger, the application needs only to signal the trigger when an event has > +happened, than the trigger turns the LED on and than keeps it off for a > +specified amount of time. > + > +This trigger is meant to be usable both for sporadic and dense events. ?In the > +first case, the trigger produces a clear single controlled blink for each > +event, while in the latter it keeps blinking at constant rate, as to signal > +that the events are arriving continuously. > + > +A one-shot LED only stays in a constant state when there are no events. ?An > +additional "invert" property specifies if the LED has to stay off (normal) or > +on (inverted) when not rearmed. > + > +The trigger can be activated from user space on led class devices as shown > +below: > + > + ?echo oneshot > trigger > + > +This adds the following sysfs attributes to the LED: > + > + ?delay_on - specifies for how many milliseconds the LED has to stay at > + ? ? ? ? ? ? LED_FULL brightness after it has been armed. > + ? ? ? ? ? ? Default to 100 ms. > + > + ?delay_off - specifies for how many milliseconds the LED has to stay at > + ? ? ? ? ? ? ?LED_OFF brightness after it has been armed. > + ? ? ? ? ? ? ?Default to 100 ms. > + > + ?invert - reverse the blink logic. ?If set to 0 (default) blink on for delay_on > + ? ? ? ? ? ms, then blink off for delay_off ms, leaving the LED normally off. ?If > + ? ? ? ? ? set to 1, blink off for delay_off ms, then blink on for delay_on ms, > + ? ? ? ? ? leaving the LED normally on. > + ? ? ? ? ? Setting this value also immediately change the LED state. > + > + ?shot - write any non-empty string to signal an events, this starts a blink > + ? ? ? ? sequence if not already running. > + > +Example use-case: network devices, initialization: > + > + ?echo oneshot > trigger # set trigger for this led > + ?echo 33 > delay_on ? ? # blink at 1 / (33 + 33) Hz on continuous traffic > + ?echo 33 > delay_off > + > +interface goes up: > + > + ?echo 1 > invert # set led as normally-on, turn the led on > + > +packet received/transmitted: > + > + ?echo 1 > shot # led starts blinking, ignored if already blinking > + > +interface goes down > + > + ?echo 0 > invert # set led as normally-off, turn the led off > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig > index 04cb8c8..1f151fb 100644 > --- a/drivers/leds/Kconfig > +++ b/drivers/leds/Kconfig > @@ -443,6 +443,20 @@ config LEDS_TRIGGER_TIMER > > ? ? ? ? ?If unsure, say Y. > > +config LEDS_TRIGGER_ONESHOT > + ? ? ? tristate "LED One-shot Trigger" > + ? ? ? depends on LEDS_TRIGGERS > + ? ? ? help > + ? ? ? ? This allows LEDs to blink in one-shot pulses with parameters > + ? ? ? ? controlled via sysfs. ?It's useful to notify the user on > + ? ? ? ? sporadic events, when there are no clear begin and end trap points, > + ? ? ? ? or on dense events, where this blinks the LED at constant rate if > + ? ? ? ? rearmed continuously. > + > + ? ? ? ? It also shows how to use the led_blink_set_oneshot() function. > + > + ? ? ? ? If unsure, say Y. > + > ?config LEDS_TRIGGER_IDE_DISK > ? ? ? ?bool "LED IDE Disk Trigger" > ? ? ? ?depends on IDE_GD_ATA > diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile > index f8958cd..9112d51 100644 > --- a/drivers/leds/Makefile > +++ b/drivers/leds/Makefile > @@ -53,6 +53,7 @@ obj-$(CONFIG_LEDS_DAC124S085) ? ? ? ? += leds-dac124s085.o > > ?# LED Triggers > ?obj-$(CONFIG_LEDS_TRIGGER_TIMER) ? ? ? += ledtrig-timer.o > +obj-$(CONFIG_LEDS_TRIGGER_ONESHOT) ? ? += ledtrig-oneshot.o > ?obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK) ? ?+= ledtrig-ide-disk.o > ?obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT) ? += ledtrig-heartbeat.o > ?obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT) ? += ledtrig-backlight.o > diff --git a/drivers/leds/ledtrig-oneshot.c b/drivers/leds/ledtrig-oneshot.c > new file mode 100644 > index 0000000..5c9edf7 > --- /dev/null > +++ b/drivers/leds/ledtrig-oneshot.c > @@ -0,0 +1,204 @@ > +/* > + * One-shot LED Trigger > + * > + * Copyright 2012, Fabio Baltieri > + * > + * Based on ledtrig-timer.c by Richard Purdie > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include "leds.h" > + > +#define DEFAULT_DELAY 100 > + > +struct oneshot_trig_data { > + ? ? ? unsigned int invert; > +}; > + > +static ssize_t led_shot(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, const char *buf, size_t size) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + ? ? ? struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; > + > + ? ? ? led_blink_set_oneshot(led_cdev, > + ? ? ? ? ? ? ? ? ? ? ? &led_cdev->blink_delay_on, &led_cdev->blink_delay_off, > + ? ? ? ? ? ? ? ? ? ? ? oneshot_data->invert); > + > + ? ? ? /* content is ignored */ > + ? ? ? return size; > +} > +static ssize_t led_invert_show(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, char *buf) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + ? ? ? struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; > + > + ? ? ? return sprintf(buf, "%u\n", oneshot_data->invert); > +} > + > +static ssize_t led_invert_store(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, const char *buf, size_t size) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + ? ? ? struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; > + ? ? ? unsigned long state; > + ? ? ? int ret; > + > + ? ? ? ret = kstrtoul(buf, 0, &state); > + ? ? ? if (ret) > + ? ? ? ? ? ? ? return ret; > + > + ? ? ? oneshot_data->invert = !!state; > + > + ? ? ? if (oneshot_data->invert) > + ? ? ? ? ? ? ? led_set_brightness(led_cdev, LED_FULL); > + ? ? ? else > + ? ? ? ? ? ? ? led_set_brightness(led_cdev, LED_OFF); > + > + ? ? ? return size; > +} > + > +static ssize_t led_delay_on_show(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, char *buf) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + > + ? ? ? return sprintf(buf, "%lu\n", led_cdev->blink_delay_on); > +} > + > +static ssize_t led_delay_on_store(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, const char *buf, size_t size) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + ? ? ? unsigned long state; > + ? ? ? int ret; > + > + ? ? ? ret = kstrtoul(buf, 0, &state); > + ? ? ? if (ret) > + ? ? ? ? ? ? ? return ret; > + > + ? ? ? led_cdev->blink_delay_on = state; > + > + ? ? ? return size; > +} > +static ssize_t led_delay_off_show(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, char *buf) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + > + ? ? ? return sprintf(buf, "%lu\n", led_cdev->blink_delay_off); > +} > + > +static ssize_t led_delay_off_store(struct device *dev, > + ? ? ? ? ? ? ? struct device_attribute *attr, const char *buf, size_t size) > +{ > + ? ? ? struct led_classdev *led_cdev = dev_get_drvdata(dev); > + ? ? ? unsigned long state; > + ? ? ? int ret; > + > + ? ? ? ret = kstrtoul(buf, 0, &state); > + ? ? ? if (ret) > + ? ? ? ? ? ? ? return ret; > + > + ? ? ? led_cdev->blink_delay_off = state; > + > + ? ? ? return size; > +} > + > +static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store); > +static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store); > +static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store); > +static DEVICE_ATTR(shot, 0200, NULL, led_shot); > + > +static void oneshot_trig_activate(struct led_classdev *led_cdev) > +{ > + ? ? ? struct oneshot_trig_data *oneshot_data; > + ? ? ? int rc; > + > + ? ? ? oneshot_data = kzalloc(sizeof(*oneshot_data), GFP_KERNEL); > + ? ? ? if (!oneshot_data) > + ? ? ? ? ? ? ? return; > + > + ? ? ? led_cdev->trigger_data = oneshot_data; > + > + ? ? ? rc = device_create_file(led_cdev->dev, &dev_attr_delay_on); > + ? ? ? if (rc) > + ? ? ? ? ? ? ? goto err_out_trig_data; > + ? ? ? rc = device_create_file(led_cdev->dev, &dev_attr_delay_off); > + ? ? ? if (rc) > + ? ? ? ? ? ? ? goto err_out_delayon; > + ? ? ? rc = device_create_file(led_cdev->dev, &dev_attr_invert); > + ? ? ? if (rc) > + ? ? ? ? ? ? ? goto err_out_delayoff; > + ? ? ? rc = device_create_file(led_cdev->dev, &dev_attr_shot); > + ? ? ? if (rc) > + ? ? ? ? ? ? ? goto err_out_invert; > + > + ? ? ? led_cdev->blink_delay_on = DEFAULT_DELAY; > + ? ? ? led_cdev->blink_delay_off = DEFAULT_DELAY; > + > + ? ? ? led_cdev->activated = true; > + > + ? ? ? return; > + > +err_out_invert: > + ? ? ? device_remove_file(led_cdev->dev, &dev_attr_invert); > +err_out_delayoff: > + ? ? ? device_remove_file(led_cdev->dev, &dev_attr_delay_off); > +err_out_delayon: > + ? ? ? device_remove_file(led_cdev->dev, &dev_attr_delay_on); > +err_out_trig_data: > + ? ? ? kfree(led_cdev->trigger_data); > +} > + > +static void oneshot_trig_deactivate(struct led_classdev *led_cdev) > +{ > + ? ? ? struct oneshot_trig_data *oneshot_data = led_cdev->trigger_data; > + > + ? ? ? if (led_cdev->activated) { > + ? ? ? ? ? ? ? device_remove_file(led_cdev->dev, &dev_attr_delay_on); > + ? ? ? ? ? ? ? device_remove_file(led_cdev->dev, &dev_attr_delay_off); > + ? ? ? ? ? ? ? device_remove_file(led_cdev->dev, &dev_attr_invert); > + ? ? ? ? ? ? ? device_remove_file(led_cdev->dev, &dev_attr_shot); > + ? ? ? ? ? ? ? kfree(oneshot_data); > + ? ? ? ? ? ? ? led_cdev->activated = false; > + ? ? ? } > + > + ? ? ? /* Stop blinking */ > + ? ? ? led_brightness_set(led_cdev, LED_OFF); > +} > + > +static struct led_trigger oneshot_led_trigger = { > + ? ? ? .name ? ? = "oneshot", > + ? ? ? .activate = oneshot_trig_activate, > + ? ? ? .deactivate = oneshot_trig_deactivate, > +}; > + > +static int __init oneshot_trig_init(void) > +{ > + ? ? ? return led_trigger_register(&oneshot_led_trigger); > +} > + > +static void __exit oneshot_trig_exit(void) > +{ > + ? ? ? led_trigger_unregister(&oneshot_led_trigger); > +} > + > +module_init(oneshot_trig_init); > +module_exit(oneshot_trig_exit); > + > +MODULE_AUTHOR("Fabio Baltieri "); > +MODULE_DESCRIPTION("One-shot LED trigger"); > +MODULE_LICENSE("GPL"); > -- > 1.7.11.rc1.9.gf623ca1.dirty > -- Bryan Wu Kernel Developer ? ?+86.186-168-78255 Mobile Canonical Ltd. ? ? ?www.canonical.com Ubuntu - Linux for human beings | www.ubuntu.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/