[PATCH v8 4/5] watchdog: Add RAVE SP watchdog driver

[PATCH v8 4/5] watchdog: Add RAVE SP watchdog driver

[Andrey Smirnov]

This driver provides access to RAVE SP watchdog functionality.

Cc: linux-kernel@vger.kernel.org
Cc: linux-watchdog@vger.kernel.org
Cc: cphealy@gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Rob Herring <robh@kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 drivers/watchdog/Kconfig       |   7 +
 drivers/watchdog/Makefile      |   1 +
 drivers/watchdog/rave-sp-wdt.c | 310 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 318 insertions(+)
 create mode 100644 drivers/watchdog/rave-sp-wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index c722cbfdc7e6..533a72248cd1 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -223,6 +223,13 @@ config ZIIRAVE_WATCHDOG
 	  To compile this driver as a module, choose M here: the
 	  module will be called ziirave_wdt.
 
+config RAVE_SP_WATCHDOG
+	tristate "RAVE SP Watchdog timer"
+	depends on RAVE_SP_CORE
+	select WATCHDOG_CORE
+	help
+	  Support for the watchdog on RAVE SP device.
+
 # ALPHA Architecture
 
 # ARM Architecture
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 56adf9fa67d0..5c9556c09f6e 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -223,3 +223,4 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
 obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
 obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
 obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
+obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
new file mode 100644
index 000000000000..86fdc7fb1f92
--- /dev/null
+++ b/drivers/watchdog/rave-sp-wdt.c
@@ -0,0 +1,310 @@
+/*
+ *  rave-sp-wdt.c - Watchdog driver preseing in RAVE SP
+ *
+ * Copyright (C) 2017 Zodiac Inflight Innovation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/rave-sp.h>
+#include <linux/watchdog.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+
+enum {
+	RAVE_SP_RESET_BYTE = 1,
+	RAVE_SP_RESET_REASON_NORMAL = 0,
+	RAVE_SP_RESET_DELAY_MS = 500,
+};
+
+struct rave_sp_wdt_variant {
+	unsigned int max_timeout;
+	unsigned int min_timeout;
+
+	int (*configure)(struct watchdog_device *);
+	int (*restart)(struct watchdog_device *);
+};
+
+struct rave_sp_wdt {
+	struct watchdog_device wdd;
+	struct rave_sp *sp;
+	const struct rave_sp_wdt_variant *variant;
+	struct notifier_block reboot_notifier;
+};
+
+static struct rave_sp_wdt *to_rave_sp_wdt(struct watchdog_device *wdd)
+{
+	return container_of(wdd, struct rave_sp_wdt, wdd);
+}
+
+static int __rave_sp_wdt_exec(struct watchdog_device *wdd,
+			      void *data,  size_t data_size,
+			      void *reply, size_t reply_size)
+{
+	return rave_sp_exec(to_rave_sp_wdt(wdd)->sp,
+			    data, data_size, reply, reply_size);
+}
+
+static int rave_sp_wdt_exec(struct watchdog_device *wdd, void *data,
+			    size_t data_size)
+{
+	return __rave_sp_wdt_exec(wdd, data, data_size, NULL, 0);
+}
+
+
+static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
+{
+	const bool enable = watchdog_hw_running(wdd);
+	u8 cmd[] = {
+		[0] = RAVE_SP_CMD_SW_WDT,
+		[1] = 0,
+		[2] = 0,
+		[3] = !!enable,
+		[4] = enable ? wdd->timeout : 0,
+	};
+	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
+}
+
+static int rave_sp_wdt_rdu_configure(struct watchdog_device *wdd)
+{
+	u8 cmd[] = {
+		[0] = RAVE_SP_CMD_SW_WDT,
+		[1] = 0,
+		[2] = watchdog_hw_running(wdd),
+		[3] = (u8) wdd->timeout,
+		[4] = (u8) (wdd->timeout >> 8),
+	};
+	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
+}
+
+static int rave_sp_wdt_configure(struct watchdog_device *wdd)
+{
+	return to_rave_sp_wdt(wdd)->variant->configure(wdd);
+}
+
+static int rave_sp_wdt_legacy_restart(struct watchdog_device *wdd)
+{
+	u8 cmd[] = {
+		[0] = RAVE_SP_CMD_RESET,
+		[1] = 0,
+		[2] = RAVE_SP_RESET_BYTE
+	};
+	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
+}
+
+static int rave_sp_wdt_rdu_restart(struct watchdog_device *wdd)
+{
+	u8 cmd[] = {
+		[0] = RAVE_SP_CMD_RESET,
+		[1] = 0,
+		[2] = RAVE_SP_RESET_BYTE,
+		[3] = RAVE_SP_RESET_REASON_NORMAL
+	};
+	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
+}
+
+static int rave_sp_wdt_reboot_notifier(struct notifier_block *nb,
+				       unsigned long action, void *data)
+{
+	/*
+	 * Restart handler is called in atomic context which means we
+	 * can't commuicate to SP via UART. Luckily for use SP will
+	 * wait 500ms before actually resetting us, so we ask it to do
+	 * so here and let the rest of the system go on wrapping
+	 * things up.
+	 */
+	if (action == SYS_DOWN || action == SYS_HALT) {
+		struct rave_sp_wdt *sp_wd =
+			container_of(nb, struct rave_sp_wdt, reboot_notifier);
+
+		const int ret = sp_wd->variant->restart(&sp_wd->wdd);
+
+		if (ret < 0)
+			dev_err(sp_wd->wdd.parent,
+				"Failed to issue restart command (%d)", ret);
+		return NOTIFY_OK;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int rave_sp_wdt_restart(struct watchdog_device *wdd,
+			       unsigned long action, void *data)
+{
+	/*
+	 * The actual work was done by reboot notifier above. SP
+	 * firmware waits 500 ms before issuing reset, so let's hang
+	 * here for one second and hopefuly we'd never reach that
+	 * return statement
+	 */
+	mdelay(RAVE_SP_RESET_DELAY_MS);
+	return -EIO;
+}
+
+static int rave_sp_wdt_start(struct watchdog_device *wdd)
+{
+	set_bit(WDOG_HW_RUNNING, &wdd->status);
+	return rave_sp_wdt_configure(wdd);
+}
+
+static int rave_sp_wdt_set_timeout(struct watchdog_device *wdd,
+				   unsigned int timeout)
+{
+	wdd->timeout = timeout;
+	return rave_sp_wdt_configure(wdd);
+}
+
+static int rave_sp_wdt_ping(struct watchdog_device *wdd)
+{
+	u8 cmd[] = {
+		[0] = RAVE_SP_CMD_PET_WDT,
+		[1] = 0,
+	};
+
+	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
+}
+
+static const struct watchdog_info rave_sp_wdt_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+	.identity = "RAVE SP Watchdog",
+};
+
+static const struct watchdog_ops rave_sp_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = rave_sp_wdt_start,
+	.stop = rave_sp_wdt_configure,
+	.ping = rave_sp_wdt_ping,
+	.set_timeout = rave_sp_wdt_set_timeout,
+	.restart = rave_sp_wdt_restart,
+};
+
+static const struct of_device_id rave_sp_wdt_of_match[] = {
+	{ .compatible = "zii,rave-sp-watchdog" },
+	{}
+};
+
+static const struct rave_sp_wdt_variant rave_sp_wdt_legacy = {
+	.max_timeout = 255,
+	.min_timeout = 1,
+	.configure = rave_sp_wdt_legacy_configure,
+	.restart   = rave_sp_wdt_legacy_restart,
+};
+
+static const struct rave_sp_wdt_variant rave_sp_wdt_rdu = {
+	.max_timeout = 180,
+	.min_timeout = 60,
+	.configure = rave_sp_wdt_rdu_configure,
+	.restart   = rave_sp_wdt_rdu_restart,
+};
+
+static const struct of_device_id rave_sp_wdt_variants[] = {
+	{ .compatible = COMPATIBLE_RAVE_SP_NIU,  .data = &rave_sp_wdt_legacy },
+	{ .compatible = COMPATIBLE_RAVE_SP_MEZZ, .data = &rave_sp_wdt_legacy },
+	{ .compatible = COMPATIBLE_RAVE_SP_ESB,  .data = &rave_sp_wdt_legacy },
+	{ .compatible = COMPATIBLE_RAVE_SP_RDU1, .data = &rave_sp_wdt_rdu    },
+	{ .compatible = COMPATIBLE_RAVE_SP_RDU2, .data = &rave_sp_wdt_rdu    },
+	{ /* sentinel */ }
+};
+
+static int rave_sp_wdt_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *id;
+	struct watchdog_device *wdd;
+	struct rave_sp_wdt *sp_wd;
+	struct nvmem_cell *cell;
+	__le16 timeout = 0;
+	int ret;
+
+	id = of_match_device(rave_sp_wdt_variants, dev->parent);
+	if (WARN_ON(!id))
+		return -ENODEV;
+
+	sp_wd = devm_kzalloc(dev, sizeof(*sp_wd), GFP_KERNEL);
+	if (!sp_wd)
+		return -ENOMEM;
+
+	sp_wd->variant = id->data;
+	sp_wd->sp      = dev_get_drvdata(dev->parent);
+
+	if (WARN_ON(!sp_wd->sp))
+		return -ENODEV;
+
+	wdd              = &sp_wd->wdd;
+	wdd->parent      = dev;
+	wdd->info        = &rave_sp_wdt_info;
+	wdd->ops         = &rave_sp_wdt_ops;
+	wdd->min_timeout = sp_wd->variant->min_timeout;
+	wdd->max_timeout = sp_wd->variant->max_timeout;
+	wdd->status      = WATCHDOG_NOWAYOUT_INIT_STATUS;
+	wdd->timeout     = 60;
+
+	cell = nvmem_cell_get(dev, "wdt_timeout");
+	if (!IS_ERR(cell)) {
+		size_t len;
+		void *value = nvmem_cell_read(cell, &len);
+
+		if (!IS_ERR(value)) {
+			memcpy(&timeout, value, min(len, sizeof(timeout)));
+			kfree(value);
+		}
+		nvmem_cell_put(cell);
+	}
+	watchdog_init_timeout(wdd, le16_to_cpu(timeout), dev);
+	watchdog_set_restart_priority(wdd, 255);
+
+	sp_wd->reboot_notifier.notifier_call = rave_sp_wdt_reboot_notifier;
+	ret = devm_register_reboot_notifier(dev, &sp_wd->reboot_notifier);
+	if (ret) {
+		dev_err(dev, "Failed to register reboot notifier\n");
+		return ret;
+	}
+
+	/*
+	 * We don't know if watchdog is running now. To be sure, let's
+	 * start it and depend on watchdog core to ping it
+	 */
+	wdd->max_hw_heartbeat_ms = wdd->max_timeout * 1000;
+	ret = rave_sp_wdt_start(wdd);
+	if (ret) {
+		dev_err(dev, "Watchdog didn't start\n");
+		return ret;
+	}
+
+	return devm_watchdog_register_device(dev, wdd);
+}
+
+static struct platform_driver rave_sp_wdt_driver = {
+	.probe = rave_sp_wdt_probe,
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = rave_sp_wdt_of_match,
+	},
+};
+
+module_platform_driver(rave_sp_wdt_driver);
+
+MODULE_DEVICE_TABLE(of, rave_sp_wdt_of_match);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");
+MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");
+MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
+MODULE_DESCRIPTION("RAVE SP Watchdog driver");
+MODULE_ALIAS("platform:rave-sp-watchdog");
-- 
2.13.5

Re: [v8,4/5] watchdog: Add RAVE SP watchdog driver

[Guenter Roeck]

On Wed, Oct 18, 2017 at 10:01:35AM -0700, Andrey Smirnov wrote:
> This driver provides access to RAVE SP watchdog functionality.
> 
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-watchdog@vger.kernel.org
> Cc: cphealy@gmail.com
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Johan Hovold <johan@kernel.org>
> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> ---
>  drivers/watchdog/Kconfig       |   7 +
>  drivers/watchdog/Makefile      |   1 +
>  drivers/watchdog/rave-sp-wdt.c | 310 +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 318 insertions(+)
>  create mode 100644 drivers/watchdog/rave-sp-wdt.c
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index c722cbfdc7e6..533a72248cd1 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -223,6 +223,13 @@ config ZIIRAVE_WATCHDOG
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called ziirave_wdt.
>  
> +config RAVE_SP_WATCHDOG
> +	tristate "RAVE SP Watchdog timer"
> +	depends on RAVE_SP_CORE
> +	select WATCHDOG_CORE
> +	help
> +	  Support for the watchdog on RAVE SP device.
> +
>  # ALPHA Architecture
>  
>  # ARM Architecture
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 56adf9fa67d0..5c9556c09f6e 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -223,3 +223,4 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
>  obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
>  obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
>  obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
> +obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
> diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
> new file mode 100644
> index 000000000000..86fdc7fb1f92
> --- /dev/null
> +++ b/drivers/watchdog/rave-sp-wdt.c
> @@ -0,0 +1,310 @@
> +/*
> + *  rave-sp-wdt.c - Watchdog driver preseing in RAVE SP

present ?

> + *
> + * Copyright (C) 2017 Zodiac Inflight Innovation
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/rave-sp.h>
> +#include <linux/watchdog.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/reboot.h>
> +#include <linux/slab.h>

Alphabetic order please.

> +
> +enum {
> +	RAVE_SP_RESET_BYTE = 1,
> +	RAVE_SP_RESET_REASON_NORMAL = 0,
> +	RAVE_SP_RESET_DELAY_MS = 500,
> +};
> +
> +struct rave_sp_wdt_variant {
> +	unsigned int max_timeout;
> +	unsigned int min_timeout;
> +
> +	int (*configure)(struct watchdog_device *);
> +	int (*restart)(struct watchdog_device *);
> +};
> +
> +struct rave_sp_wdt {
> +	struct watchdog_device wdd;
> +	struct rave_sp *sp;
> +	const struct rave_sp_wdt_variant *variant;
> +	struct notifier_block reboot_notifier;
> +};
> +
> +static struct rave_sp_wdt *to_rave_sp_wdt(struct watchdog_device *wdd)
> +{
> +	return container_of(wdd, struct rave_sp_wdt, wdd);
> +}
> +
> +static int __rave_sp_wdt_exec(struct watchdog_device *wdd,
> +			      void *data,  size_t data_size,
> +			      void *reply, size_t reply_size)
> +{
> +	return rave_sp_exec(to_rave_sp_wdt(wdd)->sp,
> +			    data, data_size, reply, reply_size);
> +}

This extra function is only called once and thus quite pointless.

> +
> +static int rave_sp_wdt_exec(struct watchdog_device *wdd, void *data,
> +			    size_t data_size)
> +{
> +	return __rave_sp_wdt_exec(wdd, data, data_size, NULL, 0);
> +}
> +
> +

Please run checkpatch --strict and fix what it reports.

> +static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
> +{
> +	const bool enable = watchdog_hw_running(wdd);
> +	u8 cmd[] = {
> +		[0] = RAVE_SP_CMD_SW_WDT,
> +		[1] = 0,
> +		[2] = 0,
> +		[3] = !!enable,

Useless !!. It converts a boolean to a boolean. Besides, isn't it always
true anyway ?

> +		[4] = enable ? wdd->timeout : 0,
> +	};

Interesting; checkpatch doesn't require an empty line after variable
declarations anymore ? Lets keep it anyway for consistency.

> +	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> +}
> +
> +static int rave_sp_wdt_rdu_configure(struct watchdog_device *wdd)
> +{
> +	u8 cmd[] = {
> +		[0] = RAVE_SP_CMD_SW_WDT,
> +		[1] = 0,
> +		[2] = watchdog_hw_running(wdd),

Nitpick, but isn't this always true ? There is no stop function,
and HW_RUNNING is set before this function is called.

> +		[3] = (u8) wdd->timeout,
> +		[4] = (u8) (wdd->timeout >> 8),
> +	};
> +	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> +}
> +
> +static int rave_sp_wdt_configure(struct watchdog_device *wdd)
> +{
> +	return to_rave_sp_wdt(wdd)->variant->configure(wdd);
> +}
> +
> +static int rave_sp_wdt_legacy_restart(struct watchdog_device *wdd)
> +{
> +	u8 cmd[] = {
> +		[0] = RAVE_SP_CMD_RESET,
> +		[1] = 0,
> +		[2] = RAVE_SP_RESET_BYTE
> +	};
> +	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> +}
> +
> +static int rave_sp_wdt_rdu_restart(struct watchdog_device *wdd)
> +{
> +	u8 cmd[] = {
> +		[0] = RAVE_SP_CMD_RESET,
> +		[1] = 0,
> +		[2] = RAVE_SP_RESET_BYTE,
> +		[3] = RAVE_SP_RESET_REASON_NORMAL
> +	};
> +	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> +}
> +
> +static int rave_sp_wdt_reboot_notifier(struct notifier_block *nb,
> +				       unsigned long action, void *data)
> +{
> +	/*
> +	 * Restart handler is called in atomic context which means we
> +	 * can't commuicate to SP via UART. Luckily for use SP will

communicate

> +	 * wait 500ms before actually resetting us, so we ask it to do
> +	 * so here and let the rest of the system go on wrapping
> +	 * things up.
> +	 */
> +	if (action == SYS_DOWN || action == SYS_HALT) {
> +		struct rave_sp_wdt *sp_wd =
> +			container_of(nb, struct rave_sp_wdt, reboot_notifier);
> +
> +		const int ret = sp_wd->variant->restart(&sp_wd->wdd);
> +
> +		if (ret < 0)
> +			dev_err(sp_wd->wdd.parent,
> +				"Failed to issue restart command (%d)", ret);
> +		return NOTIFY_OK;
> +	}
> +
> +	return NOTIFY_DONE;
> +}
> +
> +static int rave_sp_wdt_restart(struct watchdog_device *wdd,
> +			       unsigned long action, void *data)
> +{
> +	/*
> +	 * The actual work was done by reboot notifier above. SP
> +	 * firmware waits 500 ms before issuing reset, so let's hang
> +	 * here for one second and hopefuly we'd never reach that

RAVE_SP_RESET_DELAY_MS is 500(ms), not one second.

> +	 * return statement
> +	 */
> +	mdelay(RAVE_SP_RESET_DELAY_MS);
> +	return -EIO;
> +}
> +
> +static int rave_sp_wdt_start(struct watchdog_device *wdd)
> +{
> +	set_bit(WDOG_HW_RUNNING, &wdd->status);
> +	return rave_sp_wdt_configure(wdd);
> +}
> +
> +static int rave_sp_wdt_set_timeout(struct watchdog_device *wdd,
> +				   unsigned int timeout)
> +{
> +	wdd->timeout = timeout;
> +	return rave_sp_wdt_configure(wdd);
> +}
> +
> +static int rave_sp_wdt_ping(struct watchdog_device *wdd)
> +{
> +	u8 cmd[] = {
> +		[0] = RAVE_SP_CMD_PET_WDT,
> +		[1] = 0,
> +	};
> +
> +	return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> +}
> +
> +static const struct watchdog_info rave_sp_wdt_info = {
> +	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
> +	.identity = "RAVE SP Watchdog",
> +};
> +
> +static const struct watchdog_ops rave_sp_wdt_ops = {
> +	.owner = THIS_MODULE,
> +	.start = rave_sp_wdt_start,
> +	.stop = rave_sp_wdt_configure,
> +	.ping = rave_sp_wdt_ping,
> +	.set_timeout = rave_sp_wdt_set_timeout,
> +	.restart = rave_sp_wdt_restart,
> +};
> +
> +static const struct of_device_id rave_sp_wdt_of_match[] = {
> +	{ .compatible = "zii,rave-sp-watchdog" },
> +	{}
> +};
> +
> +static const struct rave_sp_wdt_variant rave_sp_wdt_legacy = {
> +	.max_timeout = 255,
> +	.min_timeout = 1,
> +	.configure = rave_sp_wdt_legacy_configure,
> +	.restart   = rave_sp_wdt_legacy_restart,
> +};
> +
> +static const struct rave_sp_wdt_variant rave_sp_wdt_rdu = {
> +	.max_timeout = 180,
> +	.min_timeout = 60,
> +	.configure = rave_sp_wdt_rdu_configure,
> +	.restart   = rave_sp_wdt_rdu_restart,
> +};
> +
> +static const struct of_device_id rave_sp_wdt_variants[] = {
> +	{ .compatible = COMPATIBLE_RAVE_SP_NIU,  .data = &rave_sp_wdt_legacy },
> +	{ .compatible = COMPATIBLE_RAVE_SP_MEZZ, .data = &rave_sp_wdt_legacy },
> +	{ .compatible = COMPATIBLE_RAVE_SP_ESB,  .data = &rave_sp_wdt_legacy },
> +	{ .compatible = COMPATIBLE_RAVE_SP_RDU1, .data = &rave_sp_wdt_rdu    },
> +	{ .compatible = COMPATIBLE_RAVE_SP_RDU2, .data = &rave_sp_wdt_rdu    },
> +	{ /* sentinel */ }
> +};
> +
> +static int rave_sp_wdt_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	const struct of_device_id *id;
> +	struct watchdog_device *wdd;
> +	struct rave_sp_wdt *sp_wd;
> +	struct nvmem_cell *cell;
> +	__le16 timeout = 0;
> +	int ret;
> +
> +	id = of_match_device(rave_sp_wdt_variants, dev->parent);
> +	if (WARN_ON(!id))
> +		return -ENODEV;
> +
> +	sp_wd = devm_kzalloc(dev, sizeof(*sp_wd), GFP_KERNEL);
> +	if (!sp_wd)
> +		return -ENOMEM;
> +
> +	sp_wd->variant = id->data;
> +	sp_wd->sp      = dev_get_drvdata(dev->parent);
> +
> +	if (WARN_ON(!sp_wd->sp))
> +		return -ENODEV;
> +
Not sure I understand the value of those tracebacks. Presumably the driver
is instantiated through its parent. Is there precedent that other drivers
in the same situation do this ?

> +	wdd              = &sp_wd->wdd;
> +	wdd->parent      = dev;
> +	wdd->info        = &rave_sp_wdt_info;
> +	wdd->ops         = &rave_sp_wdt_ops;
> +	wdd->min_timeout = sp_wd->variant->min_timeout;
> +	wdd->max_timeout = sp_wd->variant->max_timeout;
> +	wdd->status      = WATCHDOG_NOWAYOUT_INIT_STATUS;
> +	wdd->timeout     = 60;
> +
> +	cell = nvmem_cell_get(dev, "wdt_timeout");
> +	if (!IS_ERR(cell)) {
> +		size_t len;
> +		void *value = nvmem_cell_read(cell, &len);
> +
> +		if (!IS_ERR(value)) {
> +			memcpy(&timeout, value, min(len, sizeof(timeout)));
> +			kfree(value);
> +		}
> +		nvmem_cell_put(cell);
> +	}
> +	watchdog_init_timeout(wdd, le16_to_cpu(timeout), dev);
> +	watchdog_set_restart_priority(wdd, 255);
> +
> +	sp_wd->reboot_notifier.notifier_call = rave_sp_wdt_reboot_notifier;
> +	ret = devm_register_reboot_notifier(dev, &sp_wd->reboot_notifier);
> +	if (ret) {
> +		dev_err(dev, "Failed to register reboot notifier\n");
> +		return ret;
> +	}
> +
> +	/*
> +	 * We don't know if watchdog is running now. To be sure, let's
> +	 * start it and depend on watchdog core to ping it
> +	 */
> +	wdd->max_hw_heartbeat_ms = wdd->max_timeout * 1000;
> +	ret = rave_sp_wdt_start(wdd);
> +	if (ret) {
> +		dev_err(dev, "Watchdog didn't start\n");
> +		return ret;
> +	}
> +
> +	return devm_watchdog_register_device(dev, wdd);
> +}
> +
> +static struct platform_driver rave_sp_wdt_driver = {
> +	.probe = rave_sp_wdt_probe,
> +	.driver = {
> +		.name = KBUILD_MODNAME,
> +		.of_match_table = rave_sp_wdt_of_match,
> +	},
> +};
> +
> +module_platform_driver(rave_sp_wdt_driver);
> +
> +MODULE_DEVICE_TABLE(of, rave_sp_wdt_of_match);
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");
> +MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");
> +MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
> +MODULE_DESCRIPTION("RAVE SP Watchdog driver");
> +MODULE_ALIAS("platform:rave-sp-watchdog");

Re: [v8,4/5] watchdog: Add RAVE SP watchdog driver

[Joe Perches]

On Sat, 2017-10-21 at 09:47 -0700, Guenter Roeck wrote:
> On Wed, Oct 18, 2017 at 10:01:35AM -0700, Andrey Smirnov wrote:
> > This driver provides access to RAVE SP watchdog functionality.
[]
> > +static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
> > +{
> > +	const bool enable = watchdog_hw_running(wdd);
> > +	u8 cmd[] = {
> > +		[0] = RAVE_SP_CMD_SW_WDT,
> > +		[1] = 0,
> > +		[2] = 0,
> > +		[3] = !!enable,
> 
> Useless !!. It converts a boolean to a boolean. Besides, isn't it always
> true anyway ?

This converts a _Bool to an int which is cast to a u8
The !! is useless though.

> > +		[4] = enable ? wdd->timeout : 0,
> > +	};
> 
> Interesting; checkpatch doesn't require an empty line after variable
> declarations anymore ? Lets keep it anyway for consistency.

checkpatch is primarily a single line oriented parser.
Multi-line declarations aren't parsed.

Re: [v8,4/5] watchdog: Add RAVE SP watchdog driver

[Andrey Smirnov]

On Sat, Oct 21, 2017 at 9:47 AM, Guenter Roeck <linux@roeck-us.net> wrote:
> On Wed, Oct 18, 2017 at 10:01:35AM -0700, Andrey Smirnov wrote:
>> This driver provides access to RAVE SP watchdog functionality.
>>
>> Cc: linux-kernel@vger.kernel.org
>> Cc: linux-watchdog@vger.kernel.org
>> Cc: cphealy@gmail.com
>> Cc: Lucas Stach <l.stach@pengutronix.de>
>> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> Cc: Lee Jones <lee.jones@linaro.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Pavel Machek <pavel@ucw.cz>
>> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
>> Cc: Guenter Roeck <linux@roeck-us.net>
>> Cc: Rob Herring <robh@kernel.org>
>> Cc: Johan Hovold <johan@kernel.org>
>> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
>> ---
>>  drivers/watchdog/Kconfig       |   7 +
>>  drivers/watchdog/Makefile      |   1 +
>>  drivers/watchdog/rave-sp-wdt.c | 310 +++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 318 insertions(+)
>>  create mode 100644 drivers/watchdog/rave-sp-wdt.c
>>
>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>> index c722cbfdc7e6..533a72248cd1 100644
>> --- a/drivers/watchdog/Kconfig
>> +++ b/drivers/watchdog/Kconfig
>> @@ -223,6 +223,13 @@ config ZIIRAVE_WATCHDOG
>>         To compile this driver as a module, choose M here: the
>>         module will be called ziirave_wdt.
>>
>> +config RAVE_SP_WATCHDOG
>> +     tristate "RAVE SP Watchdog timer"
>> +     depends on RAVE_SP_CORE
>> +     select WATCHDOG_CORE
>> +     help
>> +       Support for the watchdog on RAVE SP device.
>> +
>>  # ALPHA Architecture
>>
>>  # ARM Architecture
>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>> index 56adf9fa67d0..5c9556c09f6e 100644
>> --- a/drivers/watchdog/Makefile
>> +++ b/drivers/watchdog/Makefile
>> @@ -223,3 +223,4 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
>>  obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
>>  obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
>>  obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
>> +obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
>> diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
>> new file mode 100644
>> index 000000000000..86fdc7fb1f92
>> --- /dev/null
>> +++ b/drivers/watchdog/rave-sp-wdt.c
>> @@ -0,0 +1,310 @@
>> +/*
>> + *  rave-sp-wdt.c - Watchdog driver preseing in RAVE SP
>
> present ?
>

Yup, my bad, will fix in v9.

>> + *
>> + * Copyright (C) 2017 Zodiac Inflight Innovation
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License as
>> + * published by the Free Software Foundation; either version 2 of
>> + * the License, or (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, see <http://www.gnu.org/licenses/>.
>> + */
>> +
>> +#include <linux/delay.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/rave-sp.h>
>> +#include <linux/watchdog.h>
>> +#include <linux/nvmem-consumer.h>
>> +#include <linux/reboot.h>
>> +#include <linux/slab.h>
>
> Alphabetic order please.
>

OK, will do.

>> +
>> +enum {
>> +     RAVE_SP_RESET_BYTE = 1,
>> +     RAVE_SP_RESET_REASON_NORMAL = 0,
>> +     RAVE_SP_RESET_DELAY_MS = 500,
>> +};
>> +
>> +struct rave_sp_wdt_variant {
>> +     unsigned int max_timeout;
>> +     unsigned int min_timeout;
>> +
>> +     int (*configure)(struct watchdog_device *);
>> +     int (*restart)(struct watchdog_device *);
>> +};
>> +
>> +struct rave_sp_wdt {
>> +     struct watchdog_device wdd;
>> +     struct rave_sp *sp;
>> +     const struct rave_sp_wdt_variant *variant;
>> +     struct notifier_block reboot_notifier;
>> +};
>> +
>> +static struct rave_sp_wdt *to_rave_sp_wdt(struct watchdog_device *wdd)
>> +{
>> +     return container_of(wdd, struct rave_sp_wdt, wdd);
>> +}
>> +
>> +static int __rave_sp_wdt_exec(struct watchdog_device *wdd,
>> +                           void *data,  size_t data_size,
>> +                           void *reply, size_t reply_size)
>> +{
>> +     return rave_sp_exec(to_rave_sp_wdt(wdd)->sp,
>> +                         data, data_size, reply, reply_size);
>> +}
>
> This extra function is only called once and thus quite pointless.
>

True. Will remove in v9.

>> +
>> +static int rave_sp_wdt_exec(struct watchdog_device *wdd, void *data,
>> +                         size_t data_size)
>> +{
>> +     return __rave_sp_wdt_exec(wdd, data, data_size, NULL, 0);
>> +}
>> +
>> +
>
> Please run checkpatch --strict and fix what it reports.
>

Sure, will do.

>> +static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
>> +{
>> +     const bool enable = watchdog_hw_running(wdd);
>> +     u8 cmd[] = {
>> +             [0] = RAVE_SP_CMD_SW_WDT,
>> +             [1] = 0,
>> +             [2] = 0,
>> +             [3] = !!enable,
>
> Useless !!. It converts a boolean to a boolean. Besides, isn't it always
> true anyway ?

Good point, will remove the "!!". This function also is called as
.stop method (via rave_sp_wdt_configure) for corresponding
"watchdog_device" and I rely on code in watchdog_stop() to clear
WDOG_HW_RUNNING. Is this not a correct thing to do?

>
>> +             [4] = enable ? wdd->timeout : 0,
>> +     };
>
> Interesting; checkpatch doesn't require an empty line after variable
> declarations anymore ? Lets keep it anyway for consistency.
>

OK, will fix in v9.

>> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> +}
>> +
>> +static int rave_sp_wdt_rdu_configure(struct watchdog_device *wdd)
>> +{
>> +     u8 cmd[] = {
>> +             [0] = RAVE_SP_CMD_SW_WDT,
>> +             [1] = 0,
>> +             [2] = watchdog_hw_running(wdd),
>
> Nitpick, but isn't this always true ? There is no stop function,
> and HW_RUNNING is set before this function is called.
>

Same as above. Let me know if relying on HW_RUNNING being cleared by
watchdog_stop() is incorrect.

>> +             [3] = (u8) wdd->timeout,
>> +             [4] = (u8) (wdd->timeout >> 8),
>> +     };
>> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> +}
>> +
>> +static int rave_sp_wdt_configure(struct watchdog_device *wdd)
>> +{
>> +     return to_rave_sp_wdt(wdd)->variant->configure(wdd);
>> +}
>> +
>> +static int rave_sp_wdt_legacy_restart(struct watchdog_device *wdd)
>> +{
>> +     u8 cmd[] = {
>> +             [0] = RAVE_SP_CMD_RESET,
>> +             [1] = 0,
>> +             [2] = RAVE_SP_RESET_BYTE
>> +     };
>> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> +}
>> +
>> +static int rave_sp_wdt_rdu_restart(struct watchdog_device *wdd)
>> +{
>> +     u8 cmd[] = {
>> +             [0] = RAVE_SP_CMD_RESET,
>> +             [1] = 0,
>> +             [2] = RAVE_SP_RESET_BYTE,
>> +             [3] = RAVE_SP_RESET_REASON_NORMAL
>> +     };
>> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> +}
>> +
>> +static int rave_sp_wdt_reboot_notifier(struct notifier_block *nb,
>> +                                    unsigned long action, void *data)
>> +{
>> +     /*
>> +      * Restart handler is called in atomic context which means we
>> +      * can't commuicate to SP via UART. Luckily for use SP will
>
> communicate
>

My bad, will fix in v9.

>> +      * wait 500ms before actually resetting us, so we ask it to do
>> +      * so here and let the rest of the system go on wrapping
>> +      * things up.
>> +      */
>> +     if (action == SYS_DOWN || action == SYS_HALT) {
>> +             struct rave_sp_wdt *sp_wd =
>> +                     container_of(nb, struct rave_sp_wdt, reboot_notifier);
>> +
>> +             const int ret = sp_wd->variant->restart(&sp_wd->wdd);
>> +
>> +             if (ret < 0)
>> +                     dev_err(sp_wd->wdd.parent,
>> +                             "Failed to issue restart command (%d)", ret);
>> +             return NOTIFY_OK;
>> +     }
>> +
>> +     return NOTIFY_DONE;
>> +}
>> +
>> +static int rave_sp_wdt_restart(struct watchdog_device *wdd,
>> +                            unsigned long action, void *data)
>> +{
>> +     /*
>> +      * The actual work was done by reboot notifier above. SP
>> +      * firmware waits 500 ms before issuing reset, so let's hang
>> +      * here for one second and hopefuly we'd never reach that
>
> RAVE_SP_RESET_DELAY_MS is 500(ms), not one second.
>

Sorry, meant to wait for twice that delay, hence one second, but wrote
incorrect code. Will fix in v9.

>> +      * return statement
>> +      */
>> +     mdelay(RAVE_SP_RESET_DELAY_MS);
>> +     return -EIO;
>> +}
>> +
>> +static int rave_sp_wdt_start(struct watchdog_device *wdd)
>> +{
>> +     set_bit(WDOG_HW_RUNNING, &wdd->status);
>> +     return rave_sp_wdt_configure(wdd);
>> +}
>> +
>> +static int rave_sp_wdt_set_timeout(struct watchdog_device *wdd,
>> +                                unsigned int timeout)
>> +{
>> +     wdd->timeout = timeout;
>> +     return rave_sp_wdt_configure(wdd);
>> +}
>> +
>> +static int rave_sp_wdt_ping(struct watchdog_device *wdd)
>> +{
>> +     u8 cmd[] = {
>> +             [0] = RAVE_SP_CMD_PET_WDT,
>> +             [1] = 0,
>> +     };
>> +
>> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> +}
>> +
>> +static const struct watchdog_info rave_sp_wdt_info = {
>> +     .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
>> +     .identity = "RAVE SP Watchdog",
>> +};
>> +
>> +static const struct watchdog_ops rave_sp_wdt_ops = {
>> +     .owner = THIS_MODULE,
>> +     .start = rave_sp_wdt_start,
>> +     .stop = rave_sp_wdt_configure,
>> +     .ping = rave_sp_wdt_ping,
>> +     .set_timeout = rave_sp_wdt_set_timeout,
>> +     .restart = rave_sp_wdt_restart,
>> +};
>> +
>> +static const struct of_device_id rave_sp_wdt_of_match[] = {
>> +     { .compatible = "zii,rave-sp-watchdog" },
>> +     {}
>> +};
>> +
>> +static const struct rave_sp_wdt_variant rave_sp_wdt_legacy = {
>> +     .max_timeout = 255,
>> +     .min_timeout = 1,
>> +     .configure = rave_sp_wdt_legacy_configure,
>> +     .restart   = rave_sp_wdt_legacy_restart,
>> +};
>> +
>> +static const struct rave_sp_wdt_variant rave_sp_wdt_rdu = {
>> +     .max_timeout = 180,
>> +     .min_timeout = 60,
>> +     .configure = rave_sp_wdt_rdu_configure,
>> +     .restart   = rave_sp_wdt_rdu_restart,
>> +};
>> +
>> +static const struct of_device_id rave_sp_wdt_variants[] = {
>> +     { .compatible = COMPATIBLE_RAVE_SP_NIU,  .data = &rave_sp_wdt_legacy },
>> +     { .compatible = COMPATIBLE_RAVE_SP_MEZZ, .data = &rave_sp_wdt_legacy },
>> +     { .compatible = COMPATIBLE_RAVE_SP_ESB,  .data = &rave_sp_wdt_legacy },
>> +     { .compatible = COMPATIBLE_RAVE_SP_RDU1, .data = &rave_sp_wdt_rdu    },
>> +     { .compatible = COMPATIBLE_RAVE_SP_RDU2, .data = &rave_sp_wdt_rdu    },
>> +     { /* sentinel */ }
>> +};
>> +
>> +static int rave_sp_wdt_probe(struct platform_device *pdev)
>> +{
>> +     struct device *dev = &pdev->dev;
>> +     const struct of_device_id *id;
>> +     struct watchdog_device *wdd;
>> +     struct rave_sp_wdt *sp_wd;
>> +     struct nvmem_cell *cell;
>> +     __le16 timeout = 0;
>> +     int ret;
>> +
>> +     id = of_match_device(rave_sp_wdt_variants, dev->parent);
>> +     if (WARN_ON(!id))
>> +             return -ENODEV;
>> +
>> +     sp_wd = devm_kzalloc(dev, sizeof(*sp_wd), GFP_KERNEL);
>> +     if (!sp_wd)
>> +             return -ENOMEM;
>> +
>> +     sp_wd->variant = id->data;
>> +     sp_wd->sp      = dev_get_drvdata(dev->parent);
>> +
>> +     if (WARN_ON(!sp_wd->sp))
>> +             return -ENODEV;
>> +
> Not sure I understand the value of those tracebacks. Presumably the driver
> is instantiated through its parent. Is there precedent that other drivers
> in the same situation do this ?
>

No precedent. I was just being paranoid. Will remove in v9.

Thanks,
Andrey Smirnov

Re: [v8,4/5] watchdog: Add RAVE SP watchdog driver

[Guenter Roeck]

On Mon, Oct 23, 2017 at 10:01:42AM -0700, Andrey Smirnov wrote:
> On Sat, Oct 21, 2017 at 9:47 AM, Guenter Roeck <linux@roeck-us.net> wrote:
> > On Wed, Oct 18, 2017 at 10:01:35AM -0700, Andrey Smirnov wrote:
> >> This driver provides access to RAVE SP watchdog functionality.
> >>
> >> Cc: linux-kernel@vger.kernel.org
> >> Cc: linux-watchdog@vger.kernel.org
> >> Cc: cphealy@gmail.com
> >> Cc: Lucas Stach <l.stach@pengutronix.de>
> >> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> >> Cc: Lee Jones <lee.jones@linaro.org>
> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> Cc: Pavel Machek <pavel@ucw.cz>
> >> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
> >> Cc: Guenter Roeck <linux@roeck-us.net>
> >> Cc: Rob Herring <robh@kernel.org>
> >> Cc: Johan Hovold <johan@kernel.org>
> >> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> >> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> >> ---
> >>  drivers/watchdog/Kconfig       |   7 +
> >>  drivers/watchdog/Makefile      |   1 +
> >>  drivers/watchdog/rave-sp-wdt.c | 310 +++++++++++++++++++++++++++++++++++++++++
> >>  3 files changed, 318 insertions(+)
> >>  create mode 100644 drivers/watchdog/rave-sp-wdt.c
> >>
> >> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> >> index c722cbfdc7e6..533a72248cd1 100644
> >> --- a/drivers/watchdog/Kconfig
> >> +++ b/drivers/watchdog/Kconfig
> >> @@ -223,6 +223,13 @@ config ZIIRAVE_WATCHDOG
> >>         To compile this driver as a module, choose M here: the
> >>         module will be called ziirave_wdt.
> >>
> >> +config RAVE_SP_WATCHDOG
> >> +     tristate "RAVE SP Watchdog timer"
> >> +     depends on RAVE_SP_CORE
> >> +     select WATCHDOG_CORE
> >> +     help
> >> +       Support for the watchdog on RAVE SP device.
> >> +
> >>  # ALPHA Architecture
> >>
> >>  # ARM Architecture
> >> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> >> index 56adf9fa67d0..5c9556c09f6e 100644
> >> --- a/drivers/watchdog/Makefile
> >> +++ b/drivers/watchdog/Makefile
> >> @@ -223,3 +223,4 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
> >>  obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
> >>  obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
> >>  obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
> >> +obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
> >> diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
> >> new file mode 100644
> >> index 000000000000..86fdc7fb1f92
> >> --- /dev/null
> >> +++ b/drivers/watchdog/rave-sp-wdt.c
> >> @@ -0,0 +1,310 @@
> >> +/*
> >> + *  rave-sp-wdt.c - Watchdog driver preseing in RAVE SP
> >
> > present ?
> >
> 
> Yup, my bad, will fix in v9.
> 
> >> + *
> >> + * Copyright (C) 2017 Zodiac Inflight Innovation
> >> + *
> >> + * This program is free software; you can redistribute it and/or
> >> + * modify it under the terms of the GNU General Public License as
> >> + * published by the Free Software Foundation; either version 2 of
> >> + * the License, or (at your option) any later version.
> >> + *
> >> + * This program is distributed in the hope that it will be useful,
> >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> >> + * GNU General Public License for more details.
> >> + *
> >> + * You should have received a copy of the GNU General Public License
> >> + * along with this program; if not, see <http://www.gnu.org/licenses/>.
> >> + */
> >> +
> >> +#include <linux/delay.h>
> >> +#include <linux/kernel.h>
> >> +#include <linux/module.h>
> >> +#include <linux/of_device.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/rave-sp.h>
> >> +#include <linux/watchdog.h>
> >> +#include <linux/nvmem-consumer.h>
> >> +#include <linux/reboot.h>
> >> +#include <linux/slab.h>
> >
> > Alphabetic order please.
> >
> 
> OK, will do.
> 
> >> +
> >> +enum {
> >> +     RAVE_SP_RESET_BYTE = 1,
> >> +     RAVE_SP_RESET_REASON_NORMAL = 0,
> >> +     RAVE_SP_RESET_DELAY_MS = 500,
> >> +};
> >> +
> >> +struct rave_sp_wdt_variant {
> >> +     unsigned int max_timeout;
> >> +     unsigned int min_timeout;
> >> +
> >> +     int (*configure)(struct watchdog_device *);
> >> +     int (*restart)(struct watchdog_device *);
> >> +};
> >> +
> >> +struct rave_sp_wdt {
> >> +     struct watchdog_device wdd;
> >> +     struct rave_sp *sp;
> >> +     const struct rave_sp_wdt_variant *variant;
> >> +     struct notifier_block reboot_notifier;
> >> +};
> >> +
> >> +static struct rave_sp_wdt *to_rave_sp_wdt(struct watchdog_device *wdd)
> >> +{
> >> +     return container_of(wdd, struct rave_sp_wdt, wdd);
> >> +}
> >> +
> >> +static int __rave_sp_wdt_exec(struct watchdog_device *wdd,
> >> +                           void *data,  size_t data_size,
> >> +                           void *reply, size_t reply_size)
> >> +{
> >> +     return rave_sp_exec(to_rave_sp_wdt(wdd)->sp,
> >> +                         data, data_size, reply, reply_size);
> >> +}
> >
> > This extra function is only called once and thus quite pointless.
> >
> 
> True. Will remove in v9.
> 
> >> +
> >> +static int rave_sp_wdt_exec(struct watchdog_device *wdd, void *data,
> >> +                         size_t data_size)
> >> +{
> >> +     return __rave_sp_wdt_exec(wdd, data, data_size, NULL, 0);
> >> +}
> >> +
> >> +
> >
> > Please run checkpatch --strict and fix what it reports.
> >
> 
> Sure, will do.
> 
> >> +static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
> >> +{
> >> +     const bool enable = watchdog_hw_running(wdd);
> >> +     u8 cmd[] = {
> >> +             [0] = RAVE_SP_CMD_SW_WDT,
> >> +             [1] = 0,
> >> +             [2] = 0,
> >> +             [3] = !!enable,
> >
> > Useless !!. It converts a boolean to a boolean. Besides, isn't it always
> > true anyway ?
> 
> Good point, will remove the "!!". This function also is called as
> .stop method (via rave_sp_wdt_configure) for corresponding
> "watchdog_device" and I rely on code in watchdog_stop() to clear
> WDOG_HW_RUNNING. Is this not a correct thing to do?
> 
> >
> >> +             [4] = enable ? wdd->timeout : 0,
> >> +     };
> >
> > Interesting; checkpatch doesn't require an empty line after variable
> > declarations anymore ? Lets keep it anyway for consistency.
> >
> 
> OK, will fix in v9.
> 
> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> >> +}
> >> +
> >> +static int rave_sp_wdt_rdu_configure(struct watchdog_device *wdd)
> >> +{
> >> +     u8 cmd[] = {
> >> +             [0] = RAVE_SP_CMD_SW_WDT,
> >> +             [1] = 0,
> >> +             [2] = watchdog_hw_running(wdd),
> >
> > Nitpick, but isn't this always true ? There is no stop function,
> > and HW_RUNNING is set before this function is called.
> >
> 
> Same as above. Let me know if relying on HW_RUNNING being cleared by
> watchdog_stop() is incorrect.
> 
Yes, it is incorrect; the knowledge that the flag is cleared before calling
the driver stop function is not part of the API. You should pass that in as
flag.

> >> +             [3] = (u8) wdd->timeout,
> >> +             [4] = (u8) (wdd->timeout >> 8),
> >> +     };
> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> >> +}
> >> +
> >> +static int rave_sp_wdt_configure(struct watchdog_device *wdd)
> >> +{
> >> +     return to_rave_sp_wdt(wdd)->variant->configure(wdd);
> >> +}
> >> +
> >> +static int rave_sp_wdt_legacy_restart(struct watchdog_device *wdd)
> >> +{
> >> +     u8 cmd[] = {
> >> +             [0] = RAVE_SP_CMD_RESET,
> >> +             [1] = 0,
> >> +             [2] = RAVE_SP_RESET_BYTE
> >> +     };
> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> >> +}
> >> +
> >> +static int rave_sp_wdt_rdu_restart(struct watchdog_device *wdd)
> >> +{
> >> +     u8 cmd[] = {
> >> +             [0] = RAVE_SP_CMD_RESET,
> >> +             [1] = 0,
> >> +             [2] = RAVE_SP_RESET_BYTE,
> >> +             [3] = RAVE_SP_RESET_REASON_NORMAL
> >> +     };
> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> >> +}
> >> +
> >> +static int rave_sp_wdt_reboot_notifier(struct notifier_block *nb,
> >> +                                    unsigned long action, void *data)
> >> +{
> >> +     /*
> >> +      * Restart handler is called in atomic context which means we
> >> +      * can't commuicate to SP via UART. Luckily for use SP will
> >
> > communicate
> >
> 
> My bad, will fix in v9.
> 
> >> +      * wait 500ms before actually resetting us, so we ask it to do
> >> +      * so here and let the rest of the system go on wrapping
> >> +      * things up.
> >> +      */
> >> +     if (action == SYS_DOWN || action == SYS_HALT) {
> >> +             struct rave_sp_wdt *sp_wd =
> >> +                     container_of(nb, struct rave_sp_wdt, reboot_notifier);
> >> +
> >> +             const int ret = sp_wd->variant->restart(&sp_wd->wdd);
> >> +
> >> +             if (ret < 0)
> >> +                     dev_err(sp_wd->wdd.parent,
> >> +                             "Failed to issue restart command (%d)", ret);
> >> +             return NOTIFY_OK;
> >> +     }
> >> +
> >> +     return NOTIFY_DONE;
> >> +}
> >> +
> >> +static int rave_sp_wdt_restart(struct watchdog_device *wdd,
> >> +                            unsigned long action, void *data)
> >> +{
> >> +     /*
> >> +      * The actual work was done by reboot notifier above. SP
> >> +      * firmware waits 500 ms before issuing reset, so let's hang
> >> +      * here for one second and hopefuly we'd never reach that
> >
> > RAVE_SP_RESET_DELAY_MS is 500(ms), not one second.
> >
> 
> Sorry, meant to wait for twice that delay, hence one second, but wrote
> incorrect code. Will fix in v9.
> 
> >> +      * return statement
> >> +      */
> >> +     mdelay(RAVE_SP_RESET_DELAY_MS);
> >> +     return -EIO;
> >> +}
> >> +
> >> +static int rave_sp_wdt_start(struct watchdog_device *wdd)
> >> +{
> >> +     set_bit(WDOG_HW_RUNNING, &wdd->status);
> >> +     return rave_sp_wdt_configure(wdd);
> >> +}
> >> +
> >> +static int rave_sp_wdt_set_timeout(struct watchdog_device *wdd,
> >> +                                unsigned int timeout)
> >> +{
> >> +     wdd->timeout = timeout;
> >> +     return rave_sp_wdt_configure(wdd);
> >> +}
> >> +
> >> +static int rave_sp_wdt_ping(struct watchdog_device *wdd)
> >> +{
> >> +     u8 cmd[] = {
> >> +             [0] = RAVE_SP_CMD_PET_WDT,
> >> +             [1] = 0,
> >> +     };
> >> +
> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
> >> +}
> >> +
> >> +static const struct watchdog_info rave_sp_wdt_info = {
> >> +     .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
> >> +     .identity = "RAVE SP Watchdog",
> >> +};
> >> +
> >> +static const struct watchdog_ops rave_sp_wdt_ops = {
> >> +     .owner = THIS_MODULE,
> >> +     .start = rave_sp_wdt_start,
> >> +     .stop = rave_sp_wdt_configure,
> >> +     .ping = rave_sp_wdt_ping,
> >> +     .set_timeout = rave_sp_wdt_set_timeout,
> >> +     .restart = rave_sp_wdt_restart,
> >> +};
> >> +
> >> +static const struct of_device_id rave_sp_wdt_of_match[] = {
> >> +     { .compatible = "zii,rave-sp-watchdog" },
> >> +     {}
> >> +};
> >> +
> >> +static const struct rave_sp_wdt_variant rave_sp_wdt_legacy = {
> >> +     .max_timeout = 255,
> >> +     .min_timeout = 1,
> >> +     .configure = rave_sp_wdt_legacy_configure,
> >> +     .restart   = rave_sp_wdt_legacy_restart,
> >> +};
> >> +
> >> +static const struct rave_sp_wdt_variant rave_sp_wdt_rdu = {
> >> +     .max_timeout = 180,
> >> +     .min_timeout = 60,
> >> +     .configure = rave_sp_wdt_rdu_configure,
> >> +     .restart   = rave_sp_wdt_rdu_restart,
> >> +};
> >> +
> >> +static const struct of_device_id rave_sp_wdt_variants[] = {
> >> +     { .compatible = COMPATIBLE_RAVE_SP_NIU,  .data = &rave_sp_wdt_legacy },
> >> +     { .compatible = COMPATIBLE_RAVE_SP_MEZZ, .data = &rave_sp_wdt_legacy },
> >> +     { .compatible = COMPATIBLE_RAVE_SP_ESB,  .data = &rave_sp_wdt_legacy },
> >> +     { .compatible = COMPATIBLE_RAVE_SP_RDU1, .data = &rave_sp_wdt_rdu    },
> >> +     { .compatible = COMPATIBLE_RAVE_SP_RDU2, .data = &rave_sp_wdt_rdu    },
> >> +     { /* sentinel */ }
> >> +};
> >> +
> >> +static int rave_sp_wdt_probe(struct platform_device *pdev)
> >> +{
> >> +     struct device *dev = &pdev->dev;
> >> +     const struct of_device_id *id;
> >> +     struct watchdog_device *wdd;
> >> +     struct rave_sp_wdt *sp_wd;
> >> +     struct nvmem_cell *cell;
> >> +     __le16 timeout = 0;
> >> +     int ret;
> >> +
> >> +     id = of_match_device(rave_sp_wdt_variants, dev->parent);
> >> +     if (WARN_ON(!id))
> >> +             return -ENODEV;
> >> +
> >> +     sp_wd = devm_kzalloc(dev, sizeof(*sp_wd), GFP_KERNEL);
> >> +     if (!sp_wd)
> >> +             return -ENOMEM;
> >> +
> >> +     sp_wd->variant = id->data;
> >> +     sp_wd->sp      = dev_get_drvdata(dev->parent);
> >> +
> >> +     if (WARN_ON(!sp_wd->sp))
> >> +             return -ENODEV;
> >> +
> > Not sure I understand the value of those tracebacks. Presumably the driver
> > is instantiated through its parent. Is there precedent that other drivers
> > in the same situation do this ?
> >
> 
> No precedent. I was just being paranoid. Will remove in v9.
> 
> Thanks,
> Andrey Smirnov

Re: [v8,4/5] watchdog: Add RAVE SP watchdog driver

[Andrey Smirnov]

On Mon, Oct 23, 2017 at 3:04 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On Mon, Oct 23, 2017 at 10:01:42AM -0700, Andrey Smirnov wrote:
>> On Sat, Oct 21, 2017 at 9:47 AM, Guenter Roeck <linux@roeck-us.net> wrote:
>> > On Wed, Oct 18, 2017 at 10:01:35AM -0700, Andrey Smirnov wrote:
>> >> This driver provides access to RAVE SP watchdog functionality.
>> >>
>> >> Cc: linux-kernel@vger.kernel.org
>> >> Cc: linux-watchdog@vger.kernel.org
>> >> Cc: cphealy@gmail.com
>> >> Cc: Lucas Stach <l.stach@pengutronix.de>
>> >> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> >> Cc: Lee Jones <lee.jones@linaro.org>
>> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> >> Cc: Pavel Machek <pavel@ucw.cz>
>> >> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
>> >> Cc: Guenter Roeck <linux@roeck-us.net>
>> >> Cc: Rob Herring <robh@kernel.org>
>> >> Cc: Johan Hovold <johan@kernel.org>
>> >> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> >> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
>> >> ---
>> >>  drivers/watchdog/Kconfig       |   7 +
>> >>  drivers/watchdog/Makefile      |   1 +
>> >>  drivers/watchdog/rave-sp-wdt.c | 310 +++++++++++++++++++++++++++++++++++++++++
>> >>  3 files changed, 318 insertions(+)
>> >>  create mode 100644 drivers/watchdog/rave-sp-wdt.c
>> >>
>> >> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>> >> index c722cbfdc7e6..533a72248cd1 100644
>> >> --- a/drivers/watchdog/Kconfig
>> >> +++ b/drivers/watchdog/Kconfig
>> >> @@ -223,6 +223,13 @@ config ZIIRAVE_WATCHDOG
>> >>         To compile this driver as a module, choose M here: the
>> >>         module will be called ziirave_wdt.
>> >>
>> >> +config RAVE_SP_WATCHDOG
>> >> +     tristate "RAVE SP Watchdog timer"
>> >> +     depends on RAVE_SP_CORE
>> >> +     select WATCHDOG_CORE
>> >> +     help
>> >> +       Support for the watchdog on RAVE SP device.
>> >> +
>> >>  # ALPHA Architecture
>> >>
>> >>  # ARM Architecture
>> >> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>> >> index 56adf9fa67d0..5c9556c09f6e 100644
>> >> --- a/drivers/watchdog/Makefile
>> >> +++ b/drivers/watchdog/Makefile
>> >> @@ -223,3 +223,4 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
>> >>  obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
>> >>  obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
>> >>  obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
>> >> +obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
>> >> diff --git a/drivers/watchdog/rave-sp-wdt.c b/drivers/watchdog/rave-sp-wdt.c
>> >> new file mode 100644
>> >> index 000000000000..86fdc7fb1f92
>> >> --- /dev/null
>> >> +++ b/drivers/watchdog/rave-sp-wdt.c
>> >> @@ -0,0 +1,310 @@
>> >> +/*
>> >> + *  rave-sp-wdt.c - Watchdog driver preseing in RAVE SP
>> >
>> > present ?
>> >
>>
>> Yup, my bad, will fix in v9.
>>
>> >> + *
>> >> + * Copyright (C) 2017 Zodiac Inflight Innovation
>> >> + *
>> >> + * This program is free software; you can redistribute it and/or
>> >> + * modify it under the terms of the GNU General Public License as
>> >> + * published by the Free Software Foundation; either version 2 of
>> >> + * the License, or (at your option) any later version.
>> >> + *
>> >> + * This program is distributed in the hope that it will be useful,
>> >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> >> + * GNU General Public License for more details.
>> >> + *
>> >> + * You should have received a copy of the GNU General Public License
>> >> + * along with this program; if not, see <http://www.gnu.org/licenses/>.
>> >> + */
>> >> +
>> >> +#include <linux/delay.h>
>> >> +#include <linux/kernel.h>
>> >> +#include <linux/module.h>
>> >> +#include <linux/of_device.h>
>> >> +#include <linux/platform_device.h>
>> >> +#include <linux/rave-sp.h>
>> >> +#include <linux/watchdog.h>
>> >> +#include <linux/nvmem-consumer.h>
>> >> +#include <linux/reboot.h>
>> >> +#include <linux/slab.h>
>> >
>> > Alphabetic order please.
>> >
>>
>> OK, will do.
>>
>> >> +
>> >> +enum {
>> >> +     RAVE_SP_RESET_BYTE = 1,
>> >> +     RAVE_SP_RESET_REASON_NORMAL = 0,
>> >> +     RAVE_SP_RESET_DELAY_MS = 500,
>> >> +};
>> >> +
>> >> +struct rave_sp_wdt_variant {
>> >> +     unsigned int max_timeout;
>> >> +     unsigned int min_timeout;
>> >> +
>> >> +     int (*configure)(struct watchdog_device *);
>> >> +     int (*restart)(struct watchdog_device *);
>> >> +};
>> >> +
>> >> +struct rave_sp_wdt {
>> >> +     struct watchdog_device wdd;
>> >> +     struct rave_sp *sp;
>> >> +     const struct rave_sp_wdt_variant *variant;
>> >> +     struct notifier_block reboot_notifier;
>> >> +};
>> >> +
>> >> +static struct rave_sp_wdt *to_rave_sp_wdt(struct watchdog_device *wdd)
>> >> +{
>> >> +     return container_of(wdd, struct rave_sp_wdt, wdd);
>> >> +}
>> >> +
>> >> +static int __rave_sp_wdt_exec(struct watchdog_device *wdd,
>> >> +                           void *data,  size_t data_size,
>> >> +                           void *reply, size_t reply_size)
>> >> +{
>> >> +     return rave_sp_exec(to_rave_sp_wdt(wdd)->sp,
>> >> +                         data, data_size, reply, reply_size);
>> >> +}
>> >
>> > This extra function is only called once and thus quite pointless.
>> >
>>
>> True. Will remove in v9.
>>
>> >> +
>> >> +static int rave_sp_wdt_exec(struct watchdog_device *wdd, void *data,
>> >> +                         size_t data_size)
>> >> +{
>> >> +     return __rave_sp_wdt_exec(wdd, data, data_size, NULL, 0);
>> >> +}
>> >> +
>> >> +
>> >
>> > Please run checkpatch --strict and fix what it reports.
>> >
>>
>> Sure, will do.
>>
>> >> +static int rave_sp_wdt_legacy_configure(struct watchdog_device *wdd)
>> >> +{
>> >> +     const bool enable = watchdog_hw_running(wdd);
>> >> +     u8 cmd[] = {
>> >> +             [0] = RAVE_SP_CMD_SW_WDT,
>> >> +             [1] = 0,
>> >> +             [2] = 0,
>> >> +             [3] = !!enable,
>> >
>> > Useless !!. It converts a boolean to a boolean. Besides, isn't it always
>> > true anyway ?
>>
>> Good point, will remove the "!!". This function also is called as
>> .stop method (via rave_sp_wdt_configure) for corresponding
>> "watchdog_device" and I rely on code in watchdog_stop() to clear
>> WDOG_HW_RUNNING. Is this not a correct thing to do?
>>
>> >
>> >> +             [4] = enable ? wdd->timeout : 0,
>> >> +     };
>> >
>> > Interesting; checkpatch doesn't require an empty line after variable
>> > declarations anymore ? Lets keep it anyway for consistency.
>> >
>>
>> OK, will fix in v9.
>>
>> >> +     return rave_sp_wdt_exec(wdd, cmd, sizeof(cmd));
>> >> +}
>> >> +
>> >> +static int rave_sp_wdt_rdu_configure(struct watchdog_device *wdd)
>> >> +{
>> >> +     u8 cmd[] = {
>> >> +             [0] = RAVE_SP_CMD_SW_WDT,
>> >> +             [1] = 0,
>> >> +             [2] = watchdog_hw_running(wdd),
>> >
>> > Nitpick, but isn't this always true ? There is no stop function,
>> > and HW_RUNNING is set before this function is called.
>> >
>>
>> Same as above. Let me know if relying on HW_RUNNING being cleared by
>> watchdog_stop() is incorrect.
>>
> Yes, it is incorrect; the knowledge that the flag is cleared before calling
> the driver stop function is not part of the API. You should pass that in as
> flag.

Good to know. Will fix in v9, then.

Thanks,
Andrey Smirnov

[PATCH v8 5/5] dt-bindings: watchdog: Add bindings for RAVE SP watchdog driver

[Andrey Smirnov]

Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-watchdog@vger.kernel.org
Cc: cphealy@gmail.com
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Rob Herring <robh@kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---
 Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt

diff --git a/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
new file mode 100644
index 000000000000..f242c3eed0dc
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
@@ -0,0 +1,10 @@
+Zodiac Inflight Innovations RAVE Supervisory Processor Watchdog
+
+Required properties:
+
+ - compatible: Should be "zii,rave-sp-watchdog"
+
+Optional properties:
+
+ - Two byte nvmem cell "wdt_timeout", specified as per
+   Documentation/devicetree/bindings/nvmem/nvmem.txt
-- 
2.13.5

Re: [PATCH v8 5/5] dt-bindings: watchdog: Add bindings for RAVE SP watchdog driver

[Rob Herring]

On Wed, Oct 18, 2017 at 10:01:36AM -0700, Andrey Smirnov wrote:

Commit msg?

> Cc: linux-kernel@vger.kernel.org
> Cc: devicetree@vger.kernel.org
> Cc: linux-watchdog@vger.kernel.org
> Cc: cphealy@gmail.com
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Johan Hovold <johan@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> ---
>  Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
> new file mode 100644
> index 000000000000..f242c3eed0dc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
> @@ -0,0 +1,10 @@
> +Zodiac Inflight Innovations RAVE Supervisory Processor Watchdog
> +
> +Required properties:
> +
> + - compatible: Should be "zii,rave-sp-watchdog"
> +

Must be a child of ? defined in ?

> +Optional properties:
> +
> + - Two byte nvmem cell "wdt_timeout", specified as per
> +   Documentation/devicetree/bindings/nvmem/nvmem.txt

prop name: definition... is the normal format.

Also, don't use '_' in property names.

Rob

Re: [PATCH v8 5/5] dt-bindings: watchdog: Add bindings for RAVE SP watchdog driver

[Andrey Smirnov]

On Tue, Oct 24, 2017 at 12:07 PM, Rob Herring <robh@kernel.org> wrote:
> On Wed, Oct 18, 2017 at 10:01:36AM -0700, Andrey Smirnov wrote:
>
> Commit msg?
>

OK, will add in v9.

>> Cc: linux-kernel@vger.kernel.org
>> Cc: devicetree@vger.kernel.org
>> Cc: linux-watchdog@vger.kernel.org
>> Cc: cphealy@gmail.com
>> Cc: Lucas Stach <l.stach@pengutronix.de>
>> Cc: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> Cc: Lee Jones <lee.jones@linaro.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Pavel Machek <pavel@ucw.cz>
>> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
>> Cc: Guenter Roeck <linux@roeck-us.net>
>> Cc: Rob Herring <robh@kernel.org>
>> Cc: Johan Hovold <johan@kernel.org>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
>> ---
>>  Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
>>
>> diff --git a/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
>> new file mode 100644
>> index 000000000000..f242c3eed0dc
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/watchdog/zii,rave-sp-wdt.txt
>> @@ -0,0 +1,10 @@
>> +Zodiac Inflight Innovations RAVE Supervisory Processor Watchdog
>> +
>> +Required properties:
>> +
>> + - compatible: Should be "zii,rave-sp-watchdog"
>> +
>
> Must be a child of ? defined in ?

Good point, will add.

>
>> +Optional properties:
>> +
>> + - Two byte nvmem cell "wdt_timeout", specified as per
>> +   Documentation/devicetree/bindings/nvmem/nvmem.txt
>
> prop name: definition... is the normal format.
>
> Also, don't use '_' in property names.
>

OK, will fix.

Thanks,
Andrey Smirnov