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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43A11C433FE for ; Thu, 28 Apr 2022 14:32:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348431AbiD1Ofc (ORCPT ); Thu, 28 Apr 2022 10:35:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348250AbiD1Ofb (ORCPT ); Thu, 28 Apr 2022 10:35:31 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4950FAAE0C; Thu, 28 Apr 2022 07:32:16 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CAADCB82DA9; Thu, 28 Apr 2022 14:32:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CD6AC385A0; Thu, 28 Apr 2022 14:32:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651156333; bh=UWru8GZaZ3MvEmpIc/sqRP2thhFeKXYUEpRuYeCOnKQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fMYKYIde7l8Qib9ryMtpNnHzGhmLdDZAmQAWeAB65QaYxS7MyzIS/KiZ9+0+2BgZT DRJA6c2p3bXj5Mg4GiAE/SRcV4r2Yb3043XYaoB+3A1Qds4p7sKdV1ke7fUkl+tYXZ zJVhTv7rtGi1I42ufJc4kBRU5RLJi0JW/D4HdwNFQZ1hUuGC7EJzOYpHc/h/qGYpDI Vplp69SeJjxEL8bMj5YIpKiQ7Dm/PmqKRYNXw5/ULUwDP41+CdalqxB6h0kUML/OJm Smpx8vCwUJ7pjJC7MXFssTDpD7hk7jp4Q0y4bGKcEbRVuZQuJczBJAqsMS1gkNLDWs dd5cHZUCwI+QQ== Received: by pali.im (Postfix) id 4FCB28A0; Thu, 28 Apr 2022 16:32:10 +0200 (CEST) Date: Thu, 28 Apr 2022 16:32:10 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Guenter Roeck Cc: Wim Van Sebroeck , Rob Herring , linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] watchdog: max63xx_wdt: Add support for specifying WDI logic via GPIO Message-ID: <20220428143210.6cbvik2kmjul3qo5@pali> References: <20220428091603.6838-1-pali@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20180716 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Thursday 28 April 2022 06:10:56 Guenter Roeck wrote: > On 4/28/22 02:16, Pali Rohár wrote: > > On some boards is WDI logic of max6370 chip connected via GPIO. So extend > > max63xx_wdt driver and DTS schema to allow specifying WDI logic via GPIO. > > > > Signed-off-by: Pali Rohár > > How is that different to just using the gpio watchdog driver ? GPIO watchdog driver does not support max6370 memory mapped configuration. With this change, max6370 can use memory mapped space for watchdog configuration and GPIO WDI for pinging. > Guenter > > > --- > > .../bindings/watchdog/maxim,max63xx.yaml | 4 +++ > > drivers/watchdog/max63xx_wdt.c | 28 +++++++++++++++++++ > > 2 files changed, 32 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/watchdog/maxim,max63xx.yaml b/Documentation/devicetree/bindings/watchdog/maxim,max63xx.yaml > > index ab9641e845db..a97aa0135ef9 100644 > > --- a/Documentation/devicetree/bindings/watchdog/maxim,max63xx.yaml > > +++ b/Documentation/devicetree/bindings/watchdog/maxim,max63xx.yaml > > @@ -27,6 +27,10 @@ properties: > > description: This is a 1-byte memory-mapped address > > maxItems: 1 > > + gpios: > > + description: Optional GPIO used for controlling WDI when WDI bit is not mapped to memory > > + maxItems: 1 > > + > > required: > > - compatible > > - reg > > diff --git a/drivers/watchdog/max63xx_wdt.c b/drivers/watchdog/max63xx_wdt.c > > index 9e1541cfae0d..eaf00c3f06a5 100644 > > --- a/drivers/watchdog/max63xx_wdt.c > > +++ b/drivers/watchdog/max63xx_wdt.c > > @@ -27,6 +27,7 @@ > > #include > > #include > > #include > > +#include > > #define DEFAULT_HEARTBEAT 60 > > #define MAX_HEARTBEAT 60 > > @@ -53,6 +54,9 @@ struct max63xx_wdt { > > void __iomem *base; > > spinlock_t lock; > > + /* GPIOs */ > > + struct gpio_desc *gpio_wdi; > > + > > /* WDI and WSET bits write access routines */ > > void (*ping)(struct max63xx_wdt *wdt); > > void (*set)(struct max63xx_wdt *wdt, u8 set); > > @@ -158,6 +162,17 @@ static const struct watchdog_info max63xx_wdt_info = { > > .identity = "max63xx Watchdog", > > }; > > +static void max63xx_gpio_ping(struct max63xx_wdt *wdt) > > +{ > > + spin_lock(&wdt->lock); > > + > > + gpiod_set_value_cansleep(wdt->gpio_wdi, 1); > > + udelay(1); > > + gpiod_set_value_cansleep(wdt->gpio_wdi, 0); > > + > > + spin_unlock(&wdt->lock); > > +} > > + > > static void max63xx_mmap_ping(struct max63xx_wdt *wdt) > > { > > u8 val; > > @@ -225,6 +240,19 @@ static int max63xx_wdt_probe(struct platform_device *pdev) > > return -EINVAL; > > } > > + wdt->gpio_wdi = devm_gpiod_get(dev, NULL, GPIOD_FLAGS_BIT_DIR_OUT); > > + if (IS_ERR(wdt->gpio_wdi) && PTR_ERR(wdt->gpio_wdi) != -ENOENT) { > > + if (PTR_ERR(wdt->gpio_wdi) != -EPROBE_DEFER) > > + dev_err(dev, "unable to request gpio: %ld\n", > > + PTR_ERR(wdt->gpio_wdi)); > > + return PTR_ERR(wdt->gpio_wdi); > > + } > > + > > + if (!IS_ERR(wdt->gpio_wdi)) > > + wdt->ping = max63xx_gpio_ping; > > + else > > + wdt->gpio_wdi = NULL; > > + > > err = max63xx_mmap_init(pdev, wdt); > > if (err) > > return err; >