From patchwork Wed May 17 15:07:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugo Villeneuve X-Patchwork-Id: 683877 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C230FC77B7F for ; Wed, 17 May 2023 15:46:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231390AbjEQPqi (ORCPT ); Wed, 17 May 2023 11:46:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231238AbjEQPqf (ORCPT ); Wed, 17 May 2023 11:46:35 -0400 Received: from mail.hugovil.com (mail.hugovil.com [162.243.120.170]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B714558B; Wed, 17 May 2023 08:46:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=hugovil.com ; s=x; h=Subject:Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=iYZEtg7pd8shIjXTbUZsXmOLd2eioSqHBYcaXseCGHM=; b=pA8xXVO8YNlITcRaUxTfPVrXlp kwsY1TLAN8mrJTMjsi3L6fMVynx3eBwFr02/75gER+fw3W7dm0SX219XgTrrXuLbScJpxmTZLHi8b 1cQRiiBsdg/mxOIp8wmwJ41oL3zFBpkKUJm5rGkGrXi75XoM6msGU5Y2tDyjsonjIpdQ=; Received: from modemcable168.174-80-70.mc.videotron.ca ([70.80.174.168]:45486 helo=pettiford.lan) by mail.hugovil.com with esmtpa (Exim 4.92) (envelope-from ) id 1pzIkz-0007IE-78; Wed, 17 May 2023 11:08:02 -0400 From: Hugo Villeneuve To: Greg Kroah-Hartman , Jiri Slaby , Lech Perczak , =?utf-8?q?Tomasz_Mo=C5=84?= Cc: hugo@hugovil.com, linux-gpio@vger.kernel.org, Hugo Villeneuve , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Date: Wed, 17 May 2023 11:07:47 -0400 Message-Id: <20230517150746.3823249-2-hugo@hugovil.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230517150746.3823249-1-hugo@hugovil.com> References: <20230517150746.3823249-1-hugo@hugovil.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 70.80.174.168 X-SA-Exim-Mail-From: hugo@hugovil.com Subject: [PATCH 2/2] serial: sc16is7xx: fix regression with GPIO configuration X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.hugovil.com) Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Hugo Villeneuve Commit 679875d1d880 ("sc16is7xx: Separate GPIOs from modem control lines") and commit 21144bab4f11 ("sc16is7xx: Handle modem status lines") changed the function of the GPIOs pins to act as modem control lines without any possibility of selecting GPIO function. As a consequence, applications that depends on GPIO lines configured by default as GPIO pins no longer work as expected. Also, the change to select modem control lines function was done only for channel A of dual UART variants (752/762). This was not documented in the log message. This new patch allows to specify GPIO or modem control line function in the device tree, and for each of the ports (A or B). This is done by using the new device-tree property named "modem-control-line-ports" (property added in separate patch). Boards that need to have GPIOS configured as modem control lines should add that property to their device tree. Here is a list of boards using the sc16is7xx driver in their device tree and that may need to be modified: arm64/boot/dts/freescale/fsl-ls1012a-frdm.dts mips/boot/dts/ingenic/cu1830-neo.dts mips/boot/dts/ingenic/cu1000-neo.dts Fixes: 679875d1d880 ("sc16is7xx: Separate GPIOs from modem control lines") Fixes: 21144bab4f11 ("sc16is7xx: Handle modem status lines") Signed-off-by: Hugo Villeneuve --- drivers/tty/serial/sc16is7xx.c | 42 ++++++++++++++++++++-------------- 1 file changed, 25 insertions(+), 17 deletions(-) diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index a7c4da3cfd2b..1a3143331c1f 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -236,7 +236,8 @@ /* IOControl register bits (Only 75x/76x) */ #define SC16IS7XX_IOCONTROL_LATCH_BIT (1 << 0) /* Enable input latching */ -#define SC16IS7XX_IOCONTROL_MODEM_BIT (1 << 1) /* Enable GPIO[7:4] as modem pins */ +#define SC16IS7XX_IOCONTROL_MODEM_A_BIT (1 << 1) /* Enable GPIO[7:4] as modem A pins */ +#define SC16IS7XX_IOCONTROL_MODEM_B_BIT (1 << 2) /* Enable GPIO[3:0] as modem B pins */ #define SC16IS7XX_IOCONTROL_SRESET_BIT (1 << 3) /* Software Reset */ /* EFCR register bits */ @@ -306,7 +307,6 @@ struct sc16is7xx_devtype { char name[10]; int nr_gpio; int nr_uart; - int has_mctrl; }; #define SC16IS7XX_RECONF_MD (1 << 0) @@ -447,35 +447,30 @@ static const struct sc16is7xx_devtype sc16is74x_devtype = { .name = "SC16IS74X", .nr_gpio = 0, .nr_uart = 1, - .has_mctrl = 0, }; static const struct sc16is7xx_devtype sc16is750_devtype = { .name = "SC16IS750", - .nr_gpio = 4, + .nr_gpio = 8, .nr_uart = 1, - .has_mctrl = 1, }; static const struct sc16is7xx_devtype sc16is752_devtype = { .name = "SC16IS752", - .nr_gpio = 0, + .nr_gpio = 8, .nr_uart = 2, - .has_mctrl = 1, }; static const struct sc16is7xx_devtype sc16is760_devtype = { .name = "SC16IS760", - .nr_gpio = 4, + .nr_gpio = 8, .nr_uart = 1, - .has_mctrl = 1, }; static const struct sc16is7xx_devtype sc16is762_devtype = { .name = "SC16IS762", - .nr_gpio = 0, + .nr_gpio = 8, .nr_uart = 2, - .has_mctrl = 1, }; static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg) @@ -1457,12 +1452,6 @@ static int sc16is7xx_probe(struct device *dev, SC16IS7XX_EFCR_RXDISABLE_BIT | SC16IS7XX_EFCR_TXDISABLE_BIT); - /* Use GPIO lines as modem status registers */ - if (devtype->has_mctrl) - sc16is7xx_port_write(&s->p[i].port, - SC16IS7XX_IOCONTROL_REG, - SC16IS7XX_IOCONTROL_MODEM_BIT); - /* Initialize kthread work structs */ kthread_init_work(&s->p[i].tx_work, sc16is7xx_tx_proc); kthread_init_work(&s->p[i].reg_work, sc16is7xx_reg_proc); @@ -1498,6 +1487,25 @@ static int sc16is7xx_probe(struct device *dev, prop, p, u) if (u < devtype->nr_uart) s->p[u].irda_mode = true; + + val = 0; + + of_property_for_each_u32(dev->of_node, "modem-control-line-ports", + prop, p, u) + if (u < devtype->nr_uart) { + /* Use GPIO lines as modem control lines */ + if (u == 0) + val |= SC16IS7XX_IOCONTROL_MODEM_A_BIT; + else if (u == 1) + val |= SC16IS7XX_IOCONTROL_MODEM_B_BIT; + } + + if (val) + regmap_update_bits( + s->regmap, + SC16IS7XX_IOCONTROL_REG << SC16IS7XX_REG_SHIFT, + SC16IS7XX_IOCONTROL_MODEM_A_BIT | + SC16IS7XX_IOCONTROL_MODEM_B_BIT, val); } #ifdef CONFIG_GPIOLIB