From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1f6WZA-0003ah-7q for barebox@lists.infradead.org; Thu, 12 Apr 2018 07:22:48 +0000 From: Sascha Hauer Date: Thu, 12 Apr 2018 09:22:23 +0200 Message-Id: <20180412072231.31207-2-s.hauer@pengutronix.de> In-Reply-To: <20180412072231.31207-1-s.hauer@pengutronix.de> References: <20180412072231.31207-1-s.hauer@pengutronix.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 1/9] mfd: da9063: reset watchdog timer To: Barebox List Cc: Enrico Scholz From: Enrico Scholz Setting the new timeout does not suffice for restarting the watchdog; the self-clearing bit in CONTROL_F must be set too. barebox does not provide a ping function in its watchdog api to restart the watchdog timer. Detect ping vs. set_timeout() by comparing the actual with the previous timeout value. Signed-off-by: Enrico Scholz Tested-by: Stefan Christ Signed-off-by: Christian Hemp --- drivers/mfd/da9063.c | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-) diff --git a/drivers/mfd/da9063.c b/drivers/mfd/da9063.c index ac303611c0..74ad5bfdab 100644 --- a/drivers/mfd/da9063.c +++ b/drivers/mfd/da9063.c @@ -28,8 +28,13 @@ struct da9063 { struct watchdog wd; struct i2c_client *client; struct device_d *dev; + unsigned int timeout; }; +/* forbidden/impossible value; timeout will be set to this value initially to + * detect ping vs. set_timeout() operations. */ +#define DA9063_INITIAL_TIMEOUT (~0u) + /* System Control and Event Registers */ #define DA9063_REG_FAULT_LOG 0x05 #define DA9063_REG_CONTROL_D 0x11 @@ -44,8 +49,25 @@ struct da9063 { #define DA9063_TWDSCALE_MASK 0x07 /* DA9063_REG_CONTROL_F (addr=0x13) */ +#define DA9063_WATCHDOG 0x01 #define DA9063_SHUTDOWN 0x02 +static int da9063_watchdog_ping(struct da9063 *priv) +{ + int ret; + u8 val; + + dev_dbg(priv->dev, "ping\n"); + + /* reset watchdog timer; register is self clearing */ + val = DA9063_WATCHDOG; + ret = i2c_write_reg(priv->client, DA9063_REG_CONTROL_F, &val, 1); + if (ret < 0) + return ret; + + return 0; +} + static int da9063_watchdog_set_timeout(struct watchdog *wd, unsigned timeout) { struct da9063 *priv = container_of(wd, struct da9063, wd); @@ -57,8 +79,14 @@ static int da9063_watchdog_set_timeout(struct watchdog *wd, unsigned timeout) if (timeout > 131) return -EINVAL; + timeout *= 1000; /* convert to ms */ + + if (timeout == priv->timeout) + /* set_timeout called with previous parameter; just ping the + * watchdog */ + goto out; + if (timeout) { - timeout *= 1000; /* convert to ms */ scale = 0; while (timeout > (2048 << scale) && scale <= 6) scale++; @@ -78,7 +106,10 @@ static int da9063_watchdog_set_timeout(struct watchdog *wd, unsigned timeout) if (ret < 0) return ret; - return 0; + priv->timeout = timeout; + +out: + return da9063_watchdog_ping(priv); } static void da9063_detect_reset_source(struct da9063 *priv) @@ -127,6 +158,7 @@ static int da9063_probe(struct device_d *dev) priv->wd.priority = of_get_watchdog_priority(dev->device_node); priv->wd.set_timeout = da9063_watchdog_set_timeout; priv->wd.hwdev = dev; + priv->timeout = DA9063_INITIAL_TIMEOUT; priv->client = to_i2c_client(dev); priv->dev = dev; -- 2.16.1 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox