Re: [RFC PATCH v5 10/10] watchdog: bd70528: Initial support for ROHM BD70528 watchdog block

[Guenter Roeck <linux@roeck-us.net>]

On 2/4/19 4:49 AM, Matti Vaittinen wrote:
> Initial support for watchdog block included in ROHM BD70528
> power management IC.
> 
> Configurations for low power states are still to be checked.
> 
> Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
> ---
>   drivers/watchdog/Kconfig       |  12 +++
>   drivers/watchdog/Makefile      |   1 +
>   drivers/watchdog/bd70528_wdt.c | 187 +++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 200 insertions(+)
>   create mode 100644 drivers/watchdog/bd70528_wdt.c
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 57f017d74a97..f30e3a3e886e 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -90,6 +90,18 @@ config SOFT_WATCHDOG_PRETIMEOUT
>   	  watchdog. Be aware that governors might affect the watchdog because it
>   	  is purely software, e.g. the panic governor will stall it!
>   
> +config BD70528_WATCHDOG
> +	tristate "ROHM BD70528 PMIC Watchdog"
> +	depends on MFD_ROHM_BD70528
> +	select WATCHDOG_CORE
> +	help
> +	  Support for the watchdog in the ROHM BD70528 PMIC. Watchdog trigger
> +	  cause system reset.
> +
> +	  Say Y here to include support for the ROHM BD70528 watchdog.
> +	  Alternatively say M to compile the driver as a module,
> +	  which will be called bd70528_wdt.
> +
>   config DA9052_WATCHDOG
>   	tristate "Dialog DA9052 Watchdog"
>   	depends on PMIC_DA9052 || COMPILE_TEST
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index a0917ef28e07..1ce87a3b1172 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -204,6 +204,7 @@ obj-$(CONFIG_WATCHDOG_SUN4V)		+= sun4v_wdt.o
>   obj-$(CONFIG_XEN_WDT) += xen_wdt.o
>   
>   # Architecture Independent
> +obj-$(CONFIG_BD70528_WATCHDOG) += bd70528_wdt.o
>   obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
>   obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
>   obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o
> diff --git a/drivers/watchdog/bd70528_wdt.c b/drivers/watchdog/bd70528_wdt.c
> new file mode 100644
> index 000000000000..c24d4cce5e9c
> --- /dev/null
> +++ b/drivers/watchdog/bd70528_wdt.c
> @@ -0,0 +1,187 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2018 ROHM Semiconductors
> +// ROHM BD70528MWV watchdog driver
> +
> +#include <linux/bcd.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/rohm-bd70528.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/watchdog.h>
> +
> +struct wdtbd70528 {
> +	struct device *dev;
> +	struct regmap *regmap;
> +	struct mutex *rtc_lock;
> +	struct watchdog_device wdt;
> +};
> +
> +static int bd70528_wdt_set_locked(struct wdtbd70528 *w, int enable)
> +{
> +	struct bd70528 *bd70528;
> +
> +	bd70528 = container_of(w->rtc_lock, struct bd70528, rtc_timer_lock);
> +	return bd70528->wdt_set(bd70528, enable, NULL);
> +}

Please add an empty line here.

> +static int bd70528_wdt_set(struct wdtbd70528 *w, int enable)
> +{
> +	int ret;
> +
> +	mutex_lock(w->rtc_lock);
> +	ret = bd70528_wdt_set_locked(w, enable);
> +	mutex_unlock(w->rtc_lock);
> +
> +	return ret;
> +}
> +
> +static int bd70528_wdt_start(struct watchdog_device *wdt)
> +{
> +	struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
> +
> +	dev_dbg(w->dev, "WDT ping...\n");
> +	return bd70528_wdt_set(w, 1);
> +}
> +
> +static int bd70528_wdt_stop(struct watchdog_device *wdt)
> +{
> +	struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
> +
> +	dev_dbg(w->dev, "WDT stopping...\n");
> +	return bd70528_wdt_set(w, 0);
> +}
> +
> +static int bd70528_wdt_set_timeout(struct watchdog_device *wdt,
> +				    unsigned int timeout)
> +{
> +	unsigned int hours;
> +	unsigned int minutes;
> +	unsigned int seconds;
> +	int ret;
> +	struct wdtbd70528 *w = watchdog_get_drvdata(wdt);
> +
> +	seconds = timeout;
> +	hours = timeout / (60 * 60);
> +	/* Maximum timeout is 1h 59m 59s => hours is 1 or 0 */
> +	if (hours)
> +		seconds -= (60 * 60);
> +	minutes = seconds / 60;
> +	seconds = seconds % 60;
> +
> +	mutex_lock(w->rtc_lock);
> +
> +	ret = bd70528_wdt_set_locked(w, 0);
> +	if (ret)
> +		goto out_unlock;
> +
> +	ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_HOUR,
> +				 BD70528_MASK_WDT_HOUR, hours);
> +	if (ret) {
> +		dev_err(w->dev, "Failed to set WDT hours\n");
> +		goto out_en_unlock;
> +	}
> +	ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_MINUTE,
> +				 BD70528_MASK_WDT_MINUTE, bin2bcd(minutes));
> +	if (ret) {
> +		dev_err(w->dev, "Failed to set WDT minutes\n");
> +		goto out_en_unlock;
> +	}
> +	ret = regmap_update_bits(w->regmap, BD70528_REG_WDT_SEC,
> +				 BD70528_MASK_WDT_SEC, bin2bcd(seconds));
> +	if (ret)
> +		dev_err(w->dev, "Failed to set WDT seconds\n");
> +	else
> +		dev_dbg(w->dev, "WDT tmo set to %u\n", timeout);
> +
> +out_en_unlock:
> +	ret = bd70528_wdt_set_locked(w, 1);
> +out_unlock:
> +	mutex_unlock(w->rtc_lock);
> +
> +	return ret;
> +}
> +
> +static const struct watchdog_info bd70528_wdt_info = {
> +	.identity = "bd70528-wdt",
> +	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
> +};
> +
> +static const struct watchdog_ops bd70528_wdt_ops = {
> +	.start		= bd70528_wdt_start,
> +	.stop		= bd70528_wdt_stop,
> +	.set_timeout	= bd70528_wdt_set_timeout,
> +};
> +
> +/* Max time we can set is 1 hour, 59 minutes and 59 seconds */
> +#define WDT_MAX_MS ((2 * 60 * 60 - 1) * 1000)
> +/* Minimum time is 1 second */
> +#define WDT_MIN_MS 1000
> +#define DEFAULT_TIMEOUT 60
> +

Please move to top, and tab-align the values.

Otherwise I am ok with the patch.

On a side note, isn't it past time to drop the RFC ?

Guenter

> +static int bd70528_wdt_probe(struct platform_device *pdev)
> +{
> +	struct bd70528 *bd70528;
> +	struct wdtbd70528 *w;
> +	int ret;
> +	unsigned int reg;
> +
> +	bd70528 = dev_get_drvdata(pdev->dev.parent);
> +	if (!bd70528) {
> +		dev_err(&pdev->dev, "No MFD driver data\n");
> +		return -EINVAL;
> +	}
> +	w = devm_kzalloc(&pdev->dev, sizeof(*w), GFP_KERNEL);
> +	if (!w)
> +		return -ENOMEM;
> +
> +	w->regmap = bd70528->chip.regmap;
> +	w->rtc_lock = &bd70528->rtc_timer_lock;
> +	w->dev = &pdev->dev;
> +
> +	w->wdt.info = &bd70528_wdt_info;
> +	w->wdt.ops =  &bd70528_wdt_ops;
> +	w->wdt.min_hw_heartbeat_ms = WDT_MIN_MS;
> +	w->wdt.max_hw_heartbeat_ms = WDT_MAX_MS;
> +	w->wdt.parent = pdev->dev.parent;
> +	w->wdt.timeout = DEFAULT_TIMEOUT;
> +	watchdog_set_drvdata(&w->wdt, w);
> +	watchdog_init_timeout(&w->wdt, 0, pdev->dev.parent);
> +
> +	ret = bd70528_wdt_set_timeout(&w->wdt, w->wdt.timeout);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to set the watchdog timeout\n");
> +		return ret;
> +	}
> +
> +	mutex_lock(w->rtc_lock);
> +	ret = regmap_read(w->regmap, BD70528_REG_WDT_CTRL, &reg);
> +	mutex_unlock(w->rtc_lock);
> +
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to get the watchdog state\n");
> +		return ret;
> +	}
> +	if (reg & BD70528_MASK_WDT_EN) {
> +		dev_dbg(&pdev->dev, "watchdog was running during probe\n");
> +		set_bit(WDOG_HW_RUNNING, &w->wdt.status);
> +	}
> +
> +	ret = devm_watchdog_register_device(&pdev->dev, &w->wdt);
> +	if (ret < 0)
> +		dev_err(&pdev->dev, "watchdog registration failed: %d\n", ret);
> +
> +	return ret;
> +}
> +static struct platform_driver bd70528_wdt = {
> +	.driver = {
> +		.name = "bd70528-wdt"
> +	},
> +	.probe = bd70528_wdt_probe,
> +};
> +
> +module_platform_driver(bd70528_wdt);
> +
> +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
> +MODULE_DESCRIPTION("BD70528 watchdog driver");
> +MODULE_LICENSE("GPL");
>