From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lothar =?UTF-8?B?V2HDn21hbm4=?= Subject: Re: [PATCH v3 1/2] drivers: watchdog: add a driver to support SAMA5D4 watchdog timer Date: Wed, 5 Aug 2015 12:40:30 +0200 Message-ID: <20150805124030.6e73b975@ipc1.ka-ro> References: <1438765043-11030-1-git-send-email-wenyou.yang@atmel.com> <1438765043-11030-2-git-send-email-wenyou.yang@atmel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1438765043-11030-2-git-send-email-wenyou.yang-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wenyou Yang Cc: wim-IQzOog9fTRqzQB+pC5nmwQ@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org, linux-watchdog-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sylvain.rochet-ETtyaVkrhkNWk0Htik3J/w@public.gmane.org, nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org 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. >=20 > 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 time= r > 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 watchdo= g > by issuing WDRSTT command to WDT_CR register with hard-coded key. >=20 > 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 >=20 > 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. > =20 > +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-$(CONFIG_USBPCWATCHDOG) +=3D pcwd_usb.o > =20 > # ARM Architecture > obj-$(CONFIG_ARM_SP805_WATCHDOG) +=3D sp805_wdt.o > +obj-$(CONFIG_AT91_SAMA5D4_WATCHDOG) +=3D at91_sama5d4_wdt.o consistency? Other AT91 entries don't have an '_' between 'AT91' and the remainder of the Kconfig name. > obj-$(CONFIG_AT91RM9200_WATCHDOG) +=3D at91rm9200_wdt.o > obj-$(CONFIG_AT91SAM9X_WATCHDOG) +=3D at91sam9_wdt.o [...] > +static irqreturn_t atmel_wdt_irq_handler(int irq, void *dev_id) > +{ > + struct atmel_wdt *wdt =3D 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[] =3D { > + { .compatible =3D "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 Wa=C3=9Fmann --=20 ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstra=C3=9Fe 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Gesch=C3=A4ftsf=C3=BChrer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info-AvR2QvxeiV7DiMYJYoSAnRvVK+yQ3ZXh@public.gmane.org ___________________________________________________________ -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html