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 9A9B5C4332F for ; Thu, 28 Apr 2022 18:25:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350900AbiD1S2e (ORCPT ); Thu, 28 Apr 2022 14:28:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47088 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348944AbiD1S2d (ORCPT ); Thu, 28 Apr 2022 14:28:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1ABF22AE10; Thu, 28 Apr 2022 11:25:18 -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 dfw.source.kernel.org (Postfix) with ESMTPS id AB483618F3; Thu, 28 Apr 2022 18:25:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3E28C385A0; Thu, 28 Apr 2022 18:25:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651170317; bh=1Uu2MgxJYfQWEwtjkRQ98VKYPYjTfjUwZcRHMMHvaRk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WGj1mmWB1iV5T6fvuyWqnKGhUXoo0yz1h6lkQSXoPHikA583j8tUOH62UHcqmDxVA AZryB6c8EBysgsrIoZDoUi3KyqtW1I0hXQp2etBJrT6DAGD4mJOmhoAkhGb+h7oPeU uj55KMY5IZGyukPhrYEkSRzETeHVpJaXYqiCztiWNyaOQv4ZOTUIca1mJrt1ULPVLh Itt+JzJweFK1ELITTaHuvAjjA37PnGrxeaNJWvBF1wobSD6sUvZ75OFBNfsEbwFzS0 0k724SoBJbb0bh+T8noR5Mo+nD8KgLYIaTRisOpc3Ee1NOdtU05JwD7dYEG4hplv5j bBY3oKIQc+TKA== Received: by pali.im (Postfix) id AA29C8A0; Thu, 28 Apr 2022 20:25:13 +0200 (CEST) Date: Thu, 28 Apr 2022 20:25:13 +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: <20220428182513.ava4ebkdclmxlf3b@pali> References: <20220428091603.6838-1-pali@kernel.org> <20220428143210.6cbvik2kmjul3qo5@pali> 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 08:29:52 Guenter Roeck wrote: > On 4/28/22 07:32, Pali Rohár wrote: > > 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. > > > > Ok, that makes sense. Comments below. > > Thanks, > Guenter > > > > 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 > > Devicetree patches needs to be separate. Ok. > > > > 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)); > > Please use dev_err_probe(). Ok. > > > > + return PTR_ERR(wdt->gpio_wdi); > > > > + } > > > > + > > > > + if (!IS_ERR(wdt->gpio_wdi)) > > > > + wdt->ping = max63xx_gpio_ping; > > > > + else > > > > + wdt->gpio_wdi = NULL; > > Why set gpio_wdi to NULL? It isn't used if the ping function is not set. I thought that it would be more safer to have NULL value stored in pointer variable as opposite of some non-NULL value used for the error reporting. But I can remove this part of the code. > > > > + > > > > err = max63xx_mmap_init(pdev, wdt); > > Doesn't this override the gpio ping function set above ? Yes, it does. I forgot to amend local change to this patch. wdt->ping has to be changed to gpio_ping _after_ max63xx_mmap_init call. I will fix all those issues in v2. > > > > if (err) > > > > return err; > > > >