From patchwork Tue Sep 14 14:38:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 512577 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 3BF1AC433EF for ; Tue, 14 Sep 2021 14:46:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1EE38610CE for ; Tue, 14 Sep 2021 14:46:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234534AbhINOrS (ORCPT ); Tue, 14 Sep 2021 10:47:18 -0400 Received: from newton.telenet-ops.be ([195.130.132.45]:49014 "EHLO newton.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234569AbhINOrD (ORCPT ); Tue, 14 Sep 2021 10:47:03 -0400 X-Greylist: delayed 420 seconds by postgrey-1.27 at vger.kernel.org; Tue, 14 Sep 2021 10:47:02 EDT Received: from baptiste.telenet-ops.be (baptiste.telenet-ops.be [IPv6:2a02:1800:120:4::f00:13]) by newton.telenet-ops.be (Postfix) with ESMTPS id 4H85ZB5MfLzMqyXn for ; Tue, 14 Sep 2021 16:38:42 +0200 (CEST) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed20:d46f:7eb5:4a37:9d14]) by baptiste.telenet-ops.be with bizsmtp id tqeg250082aSKa101qeghC; Tue, 14 Sep 2021 16:38:42 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1mQ9a3-004VGo-Kp; Tue, 14 Sep 2021 16:38:39 +0200 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1mQ9a2-0028yg-Mp; Tue, 14 Sep 2021 16:38:38 +0200 From: Geert Uytterhoeven To: Robin van der Gracht , Miguel Ojeda , Rob Herring , Paul Burton Cc: Greg Kroah-Hartman , Pavel Machek , Marek Behun , devicetree@vger.kernel.org, linux-leds@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v6 08/19] auxdisplay: linedisp: Add support for changing scroll rate Date: Tue, 14 Sep 2021 16:38:24 +0200 Message-Id: <20210914143835.511051-9-geert@linux-m68k.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210914143835.511051-1-geert@linux-m68k.org> References: <20210914143835.511051-1-geert@linux-m68k.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org If the message to display is longer than the number of characters that the display can show, the message will be scrolled. Currently the scroll rate is fixed, moving every 500 ms. Add support for changing the scroll rate through a "scroll_step_ms" device attribute in sysfs. Signed-off-by: Geert Uytterhoeven --- v6: - No changes, v5: - No changes, v4: - No changes, v3: - No changes, v2: - No changes. --- drivers/auxdisplay/line-display.c | 37 +++++++++++++++++++++++++++++-- 1 file changed, 35 insertions(+), 2 deletions(-) diff --git a/drivers/auxdisplay/line-display.c b/drivers/auxdisplay/line-display.c index 3f35199bc39f511f..03e7f104aa1add32 100644 --- a/drivers/auxdisplay/line-display.c +++ b/drivers/auxdisplay/line-display.c @@ -19,6 +19,8 @@ #include "line-display.h" +#define DEFAULT_SCROLL_RATE (HZ / 2) + /** * linedisp_scroll() - scroll the display by a character * @t: really a pointer to the private data structure @@ -50,7 +52,7 @@ static void linedisp_scroll(struct timer_list *t) linedisp->scroll_pos %= linedisp->message_len; /* rearm the timer */ - if (linedisp->message_len > num_chars) + if (linedisp->message_len > num_chars && linedisp->scroll_rate) mod_timer(&linedisp->timer, jiffies + linedisp->scroll_rate); } @@ -149,8 +151,39 @@ static ssize_t message_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_RW(message); +static ssize_t scroll_step_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct linedisp *linedisp = container_of(dev, struct linedisp, dev); + + return sysfs_emit(buf, "%u\n", jiffies_to_msecs(linedisp->scroll_rate)); +} + +static ssize_t scroll_step_ms_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct linedisp *linedisp = container_of(dev, struct linedisp, dev); + unsigned int ms; + + if (kstrtouint(buf, 10, &ms) != 0) + return -EINVAL; + + linedisp->scroll_rate = msecs_to_jiffies(ms); + if (linedisp->message && linedisp->message_len > linedisp->num_chars) { + del_timer_sync(&linedisp->timer); + if (linedisp->scroll_rate) + linedisp_scroll(&linedisp->timer); + } + + return count; +} + +static DEVICE_ATTR_RW(scroll_step_ms); + static struct attribute *linedisp_attrs[] = { &dev_attr_message.attr, + &dev_attr_scroll_step_ms.attr, NULL, }; ATTRIBUTE_GROUPS(linedisp); @@ -182,7 +215,7 @@ int linedisp_register(struct linedisp *linedisp, struct device *parent, linedisp->update = update; linedisp->buf = buf; linedisp->num_chars = num_chars; - linedisp->scroll_rate = HZ / 2; + linedisp->scroll_rate = DEFAULT_SCROLL_RATE; device_initialize(&linedisp->dev); dev_set_name(&linedisp->dev, "linedisp.%lu",