From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754335AbbCLMKr (ORCPT ); Thu, 12 Mar 2015 08:10:47 -0400 Received: from down.free-electrons.com ([37.187.137.238]:40615 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753960AbbCLMIO (ORCPT ); Thu, 12 Mar 2015 08:08:14 -0400 From: Alexandre Belloni To: Nicolas Ferre , Daniel Lezcano Cc: Boris Brezillon , Jean-Christophe Plagniol-Villard , Wim Van Sebroeck , Guenter Roeck , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, Alexandre Belloni Subject: [PATCH v5 04/10] watchdog: at91rm9200: implement restart handler Date: Thu, 12 Mar 2015 13:07:28 +0100 Message-Id: <1426162054-9987-5-git-send-email-alexandre.belloni@free-electrons.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1426162054-9987-1-git-send-email-alexandre.belloni@free-electrons.com> References: <1426162054-9987-1-git-send-email-alexandre.belloni@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Restarting the at91rm9200 is done through programming the watchdog and waiting for it to reset. Signed-off-by: Alexandre Belloni --- drivers/watchdog/at91rm9200_wdt.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c index e6fa87d85de3..41cecb55766c 100644 --- a/drivers/watchdog/at91rm9200_wdt.c +++ b/drivers/watchdog/at91rm9200_wdt.c @@ -12,6 +12,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include +#include #include #include #include @@ -23,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -53,6 +55,27 @@ static unsigned long at91wdt_busy; /* ......................................................................... */ +static int at91rm9200_restart(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + /* + * Perform a hardware reset with the use of the Watchdog timer. + */ + regmap_write(regmap_st, AT91_ST_WDMR, + AT91_ST_RSTEN | AT91_ST_EXTEN | 1); + regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST); + + mdelay(2000); + + pr_emerg("Unable to restart system\n"); + return NOTIFY_DONE; +} + +static struct notifier_block at91rm9200_restart_nb = { + .notifier_call = at91rm9200_restart, + .priority = 192, +}; + /* * Disable the watchdog. */ @@ -228,6 +251,10 @@ static int at91wdt_probe(struct platform_device *pdev) if (res) return res; + res = register_restart_handler(&at91rm9200_restart_nb); + if (res) + dev_warn(dev, "failed to register restart handler\n"); + pr_info("AT91 Watchdog Timer enabled (%d seconds%s)\n", wdt_time, nowayout ? ", nowayout" : ""); return 0; @@ -235,8 +262,13 @@ static int at91wdt_probe(struct platform_device *pdev) static int at91wdt_remove(struct platform_device *pdev) { + struct device *dev = &pdev->dev; int res; + res = unregister_restart_handler(&at91rm9200_restart_nb); + if (res) + dev_warn(dev, "failed to unregister restart handler\n"); + res = misc_deregister(&at91wdt_miscdev); if (!res) at91wdt_miscdev.parent = NULL; -- 2.1.0