Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752518AbbHEK7E (ORCPT ); Wed, 5 Aug 2015 06:59:04 -0400 Received: from mail.karo-electronics.de ([81.173.242.67]:58226 "EHLO mail.karo-electronics.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751550AbbHEK7D convert rfc822-to-8bit (ORCPT ); Wed, 5 Aug 2015 06:59:03 -0400 X-Greylist: delayed 1080 seconds by postgrey-1.27 at vger.kernel.org; Wed, 05 Aug 2015 06:59:02 EDT Date: Wed, 5 Aug 2015 12:40:30 +0200 From: Lothar =?UTF-8?B?V2HDn21hbm4=?= To: Wenyou Yang Cc: , , , , , , boris.brezillon@free-electrons.com, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, sylvain.rochet@finsecur.com, nicolas.ferre@atmel.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3 1/2] drivers: watchdog: add a driver to support SAMA5D4 watchdog timer Message-ID: <20150805124030.6e73b975@ipc1.ka-ro> In-Reply-To: <1438765043-11030-2-git-send-email-wenyou.yang@atmel.com> References: <1438765043-11030-1-git-send-email-wenyou.yang@atmel.com> <1438765043-11030-2-git-send-email-wenyou.yang@atmel.com> Organization: Ka-Ro electronics GmbH Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4008 Lines: 98 Hi, > From SAMA5D4, the watchdog timer is upgrated with a new feature, > which is describled as in the datasheet, "WDT_MR can be written > until a LOCKMR command is issued in WDT_CR". > That is to say, as long as the bootstrap and u-boot don't issue > a LOCKMR command, WDT_MR can be written more than once in the driver. > > So the SAMA5D4 watchdog driver's implementation is different from > the at91sam9260 watchdog driver implemented in file at91sam9_wdt.c. > The user application open the device file to enable the watchdog timer > hardware, and close to disable it, and set the watchdog timer timeout > by seting WDV and WDD fields of WDT_MR register, and ping the watchdog > by issuing WDRSTT command to WDT_CR register with hard-coded key. > > Signed-off-by: Wenyou Yang > --- > drivers/watchdog/Kconfig | 9 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/at91_sama5d4_wdt.c | 279 +++++++++++++++++++++++++++++++++++ > drivers/watchdog/at91sam9_wdt.h | 2 + > 4 files changed, 291 insertions(+) > create mode 100644 drivers/watchdog/at91_sama5d4_wdt.c > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index e5e7c55..4ce8346 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -152,6 +152,15 @@ config ARM_SP805_WATCHDOG > ARM Primecell SP805 Watchdog timer. This will reboot your system when > the timeout is reached. > > +config AT91_SAMA5D4_WATCHDOG > + tristate "Atmel SAMA5D4 Watchdog Timer" > + depends on ARCH_AT91 > + select WATCHDOG_CORE > + help > + Atmel SAMA5D4 watchdog timer is embedded into SAMA5D4 chips. > + Its Watchdog Timer Mode Register can be written more than once. > + This will reboot your system when the timeout is reached. > + > config AT91RM9200_WATCHDOG > tristate "AT91RM9200 watchdog" > depends on SOC_AT91RM9200 && MFD_SYSCON > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 5c19294..c57569c 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -30,6 +30,7 @@ obj-$(CONFIG_USBPCWATCHDOG) += pcwd_usb.o > > # ARM Architecture > obj-$(CONFIG_ARM_SP805_WATCHDOG) += sp805_wdt.o > +obj-$(CONFIG_AT91_SAMA5D4_WATCHDOG) += at91_sama5d4_wdt.o consistency? Other AT91 entries don't have an '_' between 'AT91' and the remainder of the Kconfig name. > obj-$(CONFIG_AT91RM9200_WATCHDOG) += at91rm9200_wdt.o > obj-$(CONFIG_AT91SAM9X_WATCHDOG) += at91sam9_wdt.o [...] > +static irqreturn_t atmel_wdt_irq_handler(int irq, void *dev_id) > +{ > + struct atmel_wdt *wdt = platform_get_drvdata(dev_id); > + > + if (wdt_read(wdt, AT91_WDT_SR)) { > + pr_crit("Atmel Watchdog Software Reset\n"); > + emergency_restart(); > + pr_crit("Reboot didn't ?????\n"); > Reboot didn't what? 'succeed' perhaps? > +static const struct of_device_id atmel_wdt_of_match[] = { > + { .compatible = "atmel,sama5d4-wdt", }, > + { }, The empty initializer must always be the last element of the array, so there is no point in having a trailing ',' (whose purpose is to facilitate adding more entries after the last one). Without the comma there will be a compile error if (e.g. due to a badly resolved merge conflict) an additional entry would be added after the stop marker. With the comma after the stop marker any trailing entries would silently be ignored. Lothar Waßmann -- ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstraße 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Geschäftsführer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info@karo-electronics.de ___________________________________________________________ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/