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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 8A451C43460 for ; Thu, 22 Apr 2021 08:05:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 560CB61460 for ; Thu, 22 Apr 2021 08:05:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230270AbhDVIGI (ORCPT ); Thu, 22 Apr 2021 04:06:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:43768 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229655AbhDVIGH (ORCPT ); Thu, 22 Apr 2021 04:06:07 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3B6996144D; Thu, 22 Apr 2021 08:05:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619078731; bh=PODUqFe/MkmI//guL+vehGy2dzp1+CHR2OIJwFQUt60=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tRD33ycChAfFDXj+qLVp0Ps7dxkPS64X12Sxudba8Jy8Lx74JL9Mx3/5CUeKI7z5K OEkH2dVrS1EeQLgy9zvE9QrI65jK7h8fEZXK+Psq/WLI6UkoI3dyf56d359qkQhLjx xXhHeusa8Z7ks1nqh3mzEItQ+tUC3GtoEtOcNSEE= Date: Thu, 22 Apr 2021 10:05:28 +0200 From: Greg Kroah-Hartman To: Juergen Borleis Cc: linux-leds@vger.kernel.org, Pavel Machek , Jonathan Corbet , linux-doc@vger.kernel.org, Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , linux-kernel@vger.kernel.org, kernel@pengutronix.de Subject: Re: [PATCH] leds: trigger/tty: feature data direction Message-ID: References: <20210422074702.8831-1-jbe@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210422074702.8831-1-jbe@pengutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Thu, Apr 22, 2021 at 09:47:02AM +0200, Juergen Borleis wrote: > The current implementation just signals a visible feedback on all kind of > activity on the corresponding TTY. But sometimes it is useful to see what > kind of activity just happens. This change adds the capability to filter > the direction of TTY's data flow. It enables a user to forward both > directions to separate LEDs for tx and rx on demand. Default behavior is > still both directions. > > Signed-off-by: Juergen Borleis > --- > Documentation/leds/ledtrig-tty.rst | 47 ++++++++++++++++++++++++++ > drivers/leds/trigger/ledtrig-tty.c | 53 +++++++++++++++++++++++++++++- > 2 files changed, 99 insertions(+), 1 deletion(-) > create mode 100644 Documentation/leds/ledtrig-tty.rst > > diff --git a/Documentation/leds/ledtrig-tty.rst b/Documentation/leds/ledtrig-tty.rst > new file mode 100644 > index 00000000..6fc765c > --- /dev/null > +++ b/Documentation/leds/ledtrig-tty.rst > @@ -0,0 +1,47 @@ > +=============== > +LED TTY Trigger > +=============== > + > +This LED trigger flashes the LED whenever some data flows are happen on the > +corresponding TTY device. The TTY device can be freely selected, as well as the > +data flow direction. > + > +TTY trigger can be enabled and disabled from user space on led class devices, > +that support this trigger as shown below:: > + > + echo tty > trigger > + echo none > trigger > + > +This trigger exports two properties, 'ttyname' and 'dirfilter'. When the > +tty trigger is activated both properties are set to default values, which means > +no related TTY device yet and the LED would flash on both directions. > + > +Selecting a corresponding trigger TTY:: > + > + echo ttyS0 > ttyname > + > +This LED will now flash on data flow in both directions of 'ttyS0'. > + > +Selecting a direction:: > + > + echo in > dirfilter > + echo out > dirfilter > + echo inout > dirfilter > + > +This selection will flash the LED on data flow in the selected direction. > + > +Example > +======= > + > +With the 'dirfilter' property one can use two LEDs to give a user a separate > +visual feedback about data flow. > + > +Flash on data send on one LED:: > + > + echo ttyS0 > ttyname > + echo out > dirfilter > + > +Flash on data receive on a second LED:: > + > + echo ttyS0 > ttyname > + echo in > dirfilter > diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c > index f62db7e..d3bd231 100644 > --- a/drivers/leds/trigger/ledtrig-tty.c > +++ b/drivers/leds/trigger/ledtrig-tty.c > @@ -14,6 +14,8 @@ struct ledtrig_tty_data { > const char *ttyname; > struct tty_struct *tty; > int rx, tx; > + unsigned indirection:1; > + unsigned outdirection:1; > }; > > static void ledtrig_tty_restart(struct ledtrig_tty_data *trigger_data) > @@ -76,6 +78,47 @@ static ssize_t ttyname_store(struct device *dev, > } > static DEVICE_ATTR_RW(ttyname); > > +static ssize_t dirfilter_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct ledtrig_tty_data *trigger_data = led_trigger_get_drvdata(dev); > + > + if (trigger_data->indirection) > + return (ssize_t)sprintf(buf, "in\n"); > + if (trigger_data->outdirection) > + return (ssize_t)sprintf(buf, "out\n"); > + return (ssize_t)sprintf(buf, "inout\n"); sysfs_emit() please. And you are adding new sysfs files, that requires an update to Documentation/ABI/ please do so. But why are you adding random new sysfs values to a class device? That feels really wrong. thanks, greg k-h