[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linaro-dev
Subject:    [PATCH 05/07] Watchdog: DA9052/53 watchdog support v1
From:       shubhrajyoti () ti ! com (Shubhrajyoti)
Date:       2012-03-30 10:16:40
Message-ID: 4F758538.4050104 () ti ! com
[Download RAW message or body]

Hi Ashish,
Some comments / suggestions .

On Friday 30 March 2012 03:02 PM, Ashish Jangam wrote:
> Any update on this patch?
> On Tue, 2012-03-13 at 17:57 +0530, Ashish Jangam wrote:
> > Any update on below patch?
> > On Mon, 2012-02-06 at 18:18 +0530, Ashish Jangam wrote:
> > > This driver adds support for the watchdog functionality provided by the
> > > Dialog Semiconductor DA9052/53 PMIC chip.
> > > 
> > > This patch is functionally tested on Samsung SMDKV6410.
> > > 
> > > Signed-off-by: David Dajun Chen <dchen at diasemi.com>
> > > Signed-off-by: Ashish Jangam <ashish.jangam at kpitcummins.com>
> > > ---
> > > Documentation/watchdog/watchdog-parameters.txt |    5 +
> > > drivers/watchdog/Kconfig                       |    6 +
> > > drivers/watchdog/Makefile                      |    1 +
> > > drivers/watchdog/da9052_wdt.c                  |  333 ++++++++++++++++++++++++
> > > 4 files changed, 345 insertions(+), 0 deletions(-)
> > > create mode 100644 drivers/watchdog/da9052_wdt.c
> > > diff --git a/Documentation/watchdog/watchdog-parameters.txt \
> > > b/Documentation/watchdog/watchdog-parameters.txt index 17ddd82..04fddba 100644
> > > --- a/Documentation/watchdog/watchdog-parameters.txt
> > > +++ b/Documentation/watchdog/watchdog-parameters.txt
> > > @@ -78,6 +78,11 @@ wd0_timeout: Default watchdog0 timeout in 1/10secs
> > > wd1_timeout: Default watchdog1 timeout in 1/10secs
> > > wd2_timeout: Default watchdog2 timeout in 1/10secs
> > > -------------------------------------------------
> > > +da9052wdt:
> > > +timeout: Watchdog timeout in seconds. 2<= timeout <=131, default=2.048s
> > > +nowayout: Watchdog cannot be stopped once started
> > > +	(default=kernel config parameter)
> > > +-------------------------------------------------
> > > davinci_wdt:
> > > heartbeat: Watchdog heartbeat period in seconds from 1 to 600, default 60
> > > -------------------------------------------------
> > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> > > index 877b107..3fb9633 100644
> > > --- a/drivers/watchdog/Kconfig
> > > +++ b/drivers/watchdog/Kconfig
> > > @@ -63,6 +63,12 @@ config SOFT_WATCHDOG
> > > 	  To compile this driver as a module, choose M here: the
> > > 	  module will be called softdog.
> > > 
> > > +config DA9052_WATCHDOG
> > > +	tristate "Dialog DA9052/DA9053 Watchdog"
> > > +	depends on PMIC_DA9052
> > > +	help
> > > +	  Support for the watchdog in the DA9052-BC and DA9053-AA/Bx PMICs.
May be you can consider some documentation on module compilation.
> > > +
> > > config WM831X_WATCHDOG
> > > 	tristate "WM831x watchdog"
> > > 	depends on MFD_WM831X
> > > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> > > index e8f479a..0ecbe5a 100644
> > > --- a/drivers/watchdog/Makefile
> > > +++ b/drivers/watchdog/Makefile
> > > @@ -166,4 +166,5 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
> > > obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
> > > obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
> > > obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o
> > > +obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
> > > obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
> > > diff --git a/drivers/watchdog/da9052_wdt.c b/drivers/watchdog/da9052_wdt.c
> > > new file mode 100644
> > > index 0000000..b08091e
> > > --- /dev/null
> > > +++ b/drivers/watchdog/da9052_wdt.c
> > > @@ -0,0 +1,333 @@
> > > +/*
> > > + * System monitoring driver for DA9052 PMICs.
> > > + *
> > > + * Copyright(c) 2012 Dialog Semiconductor Ltd.
> > > + *
> > > + * Author: Dajun Chen <dchen at diasemi.com>
> > > + *
> > > + * 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.
> > > + *
> > > + */
> > > +
> > > +#include <linux/miscdevice.h>
> > > +#include <linux/module.h>
> > > +#include <linux/delay.h>
> > > +#include <linux/fs.h>
> > > +#include <linux/uaccess.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/time.h>
> > > +#include <linux/watchdog.h>
> > > +#include <linux/types.h>
> > > +#include <linux/kernel.h>
> > > +
> > > +#include <linux/mfd/da9052/reg.h>
> > > +#include <linux/mfd/da9052/da9052.h>
> > > +
> > > +static int nowayout = WATCHDOG_NOWAYOUT;
So it is initialised regardless of any compile time options?
> > > +static int wdt_state = WDIOS_DISABLECARD;
> > > +static struct miscdevice da9052_wdt_miscdev;
> > > +static unsigned long da9052_wdt_users;
> > > +static int da9052_wdt_expect_close;
> > > +struct da9052 *da9052;
Is this needed ?
> > > +static DEFINE_MUTEX(wdt_mutex);
> > > +
> > > +static struct {
> > > +	u8 reg_val;
> > > +	int time;  /* Seconds */
> > > +} da9052_wdt_maps[] = {
> > > +	{ 1, 2 },
> > > +	{ 2, 4 },
> > > +	{ 3, 8 },
> > > +	{ 4, 16 },
> > > +	{ 5, 32 },
> > > +	{ 5, 33 },  /* Actual time  32.768s so included both 32s and 33s */
> > > +	{ 6, 65 },
> > > +	{ 6, 66 },  /* Actual time 65.536s so include both, 65s and 66s */
> > > +	{ 7, 131 },
> > > +};
> > > +
> > > +static int da9052_wdt_set_timeout(struct da9052 *da9052, unsigned char \
> > > timeout) +{
> > > +	int ret;
> > > +
> > > +	/* Disable the Watchdog timer for 150us before changing the
> > > +	*  time out value
> > > +	*/
> > > +	ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
> > > +				DA9052_CONTROLD_TWDSCALE, 0);
> > > +	if (ret < 0) {
> > > +		dev_err(da9052->dev, "Failed to disable watchdog bit, %d\n",
> > > +			ret);
> > > +		return ret;
> > > +	}
> > > +
> > > +	mutex_lock(&wdt_mutex);
> > > +	wdt_state = (timeout == 0) ? WDIOS_DISABLECARD : WDIOS_ENABLECARD;
> > > +	mutex_unlock(&wdt_mutex);
> > > +
> > > +	if (timeout) {
> > > +		udelay(150);
Could you explain the delay?
> > > +
> > > +		/* Set the desired timeout */
> > > +		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
> > > +					DA9052_CONTROLD_TWDSCALE, timeout);
> > > +		if (ret < 0) {
> > > +			dev_err(da9052->dev,
> > > +				"Failed to update timescale bit, %d\n", ret);
> > > +			return ret;
> > > +		}
> > > +	}
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int da9052_wdt_start(struct da9052 *da9052)
> > > +{
> > > +	int ret = 0;
> > > +
> > > +
> > > +	if (wdt_state == WDIOS_DISABLECARD) {
> > > +		/* Default 2.048s */
> > > +		ret = da9052_wdt_set_timeout(da9052, 1);
> > > +		if (ret <= 0)
> > > +			goto err;
> > > +
> > > +		mutex_lock(&wdt_mutex);
> > > +		wdt_state = WDIOS_ENABLECARD;
> > > +		mutex_unlock(&wdt_mutex);
> > > +	}
> > > +
> > > +err:
> > > +	return ret;
> > > +}
> > > +
> > > +static int da9052_wdt_stop(struct da9052 *da9052)
> > > +{
> > > +	int ret = 0;
> > > +
> > > +	mutex_lock(&wdt_mutex);
> > > +
> > > +	if (wdt_state == WDIOS_ENABLECARD) {
> > > +		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
> > > +					DA9052_CONTROLD_TWDSCALE, 0);
> > > +		if (ret < 0) {
> > > +			dev_err(da9052->dev,
> > > +				"Failed to disable watchdog bit strobe bit, %d\n",
> > > +				ret);
> > > +			goto err;
> > > +		}
> > > +
> > > +		wdt_state = WDIOS_DISABLECARD;
> > > +	}
> > > +
> > > +err:
> > > +	mutex_unlock(&wdt_mutex);
> > > +	return ret;
> > > +}
> > > +
> > > +static void da9052_wdt_strobe(struct da9052 *da9052)
> > > +{
> > > +	int ret;
> > > +
> > > +	if (wdt_state == WDIOS_ENABLECARD) {
> > > +		ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
> > > +					DA9052_CONTROLD_WATCHDOG, 1 << 7);
> > > +		if (ret < 0) {
> > > +			dev_err(da9052->dev,
> > > +				"Failed to update watchdog strobe bit, %d\n",
> > > +				ret);
> > > +			return;
> > > +		}
> > > +	}
> > > +}
> > > +
> > > +static int da9052_wdt_open(struct inode *inode, struct file *file)
> > > +{
> > > +	int ret;
> > > +
> > > +	if (test_and_set_bit(0, &da9052_wdt_users))
> > > +		return -EBUSY;
> > > +
> > > +	ret = da9052_wdt_start(da9052);
> > > +	if (ret < 0)
> > > +		return ret;
> > > +
> > > +	return nonseekable_open(inode, file);
> > > +}
> > > +
> > > +static int da9052_wdt_release(struct inode *inode, struct file *file)
> > > +{
> > > +	int ret = 0;
> > > +
> > > +	if (da9052_wdt_expect_close == 42)
> > > +		ret = da9052_wdt_stop(da9052);
> > > +	else
> > > +		da9052_wdt_strobe(da9052);
> > > +
> > > +	da9052_wdt_expect_close = 0;
> > > +	clear_bit(0, &da9052_wdt_users);
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static struct watchdog_info da9052_wdt_info = {
> > > +	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
> > > +	.identity	= "DA9052 Watchdog",
> > > +};
> > > +
> > > +static long da9052_wdt_ioctl(struct file *file, uint cmd, unsigned long arg)
> > > +{
> > > +	void __user *argp = (void __user *)arg;
> > > +	int ret = 0, timeout, i, __user *p = argp;
> > > +
> > > +	switch (cmd) {
> > > +	case WDIOC_GETSUPPORT:
> > > +		ret = copy_to_user(argp, &da9052_wdt_info,
> > > +				   sizeof(da9052_wdt_info)) ? -EFAULT : 0;
> > > +		break;
> > > +	case WDIOC_GETSTATUS:
> > > +	case WDIOC_GETBOOTSTATUS:
> > > +		ret = put_user(0, p);
Did not understand this?
> > > +		break;
> > > +	case WDIOC_SETOPTIONS:
> > > +	{
> > > +		int options;
> > > +		ret = get_user(options, p);
> > > +		if (ret)
> > > +			break;
> > > +
> > > +		if (options == WDIOS_ENABLECARD)
> > > +			ret = da9052_wdt_start(da9052);
> > > +
> > > +		if (options == WDIOS_DISABLECARD)
> > > +			ret = da9052_wdt_stop(da9052);
> > > +
> > > +		break;
> > > +	}
> > > +	case WDIOC_KEEPALIVE:
> > > +		da9052_wdt_strobe(da9052);
> > > +		break;
> > > +	case WDIOC_SETTIMEOUT:
> > > +		ret = get_user(timeout, p);
> > > +		if (ret)
> > > +			break;
> > > +
> > > +		for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
> > > +			if (da9052_wdt_maps[i].time == timeout)
> > > +				break;
> > > +		if (i == ARRAY_SIZE(da9052_wdt_maps))
> > > +			ret = -EINVAL;
> > > +		else
> > > +			ret = da9052_wdt_set_timeout(da9052,
> > > +						    da9052_wdt_maps[i].reg_val);
> > > +
> > > +		break;
> > > +	case WDIOC_GETTIMEOUT:
> > > +		ret = da9052_reg_read(da9052, DA9052_CONTROL_D_REG);
> > > +		if (ret < 0)
> > > +			break;
> > > +
> > > +		ret &= DA9052_CONTROLD_TWDSCALE;
> > > +		for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
> > > +			if (da9052_wdt_maps[i].reg_val == ret)
> > > +				break;
> > > +		if (i == ARRAY_SIZE(da9052_wdt_maps))
> > > +			ret = -EINVAL;
> > > +		else
> > > +			ret = put_user(da9052_wdt_maps[i].time, p);
> > > +
> > > +		break;
> > > +	default:
> > > +		return -ENOTTY;
> > > +	}
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static ssize_t da9052_wdt_write(struct file *file,
> > > +				const char __user *data, size_t count,
> > > +				loff_t *ppos)
> > > +{
> > > +	size_t i;
> > > +
> > > +	/* Check the magic character 'V' and reload the timer */
> > > +	if (count) {
> > > +		if (!nowayout) {
> > > +			da9052_wdt_expect_close = 0;
> > > +
> > > +			/* scan for magic character */
> > > +			for (i = 0; i != count; i++) {
> > > +				char c;
> > > +				if (get_user(c, data + i))
> > > +					return -EFAULT;
> > > +				if (c == 'V')
> > > +					da9052_wdt_expect_close = 42;
> > > +			}
> > > +		/* someone wrote to us, we should reload the timer */
> > > +		da9052_wdt_strobe(da9052);
> > > +		}
> > > +	}
> > > +	return count;
> > > +}
> > > +
> > > +static const struct file_operations da9052_wdt_fops = {
> > > +	.owner		= THIS_MODULE,
> > > +	.llseek		= no_llseek,
> > > +	.unlocked_ioctl	= da9052_wdt_ioctl,
> > > +	.write		= da9052_wdt_write,
> > > +	.open		= da9052_wdt_open,
> > > +	.release	= da9052_wdt_release,
> > > +};
> > > +
> > > +static struct miscdevice da9052_wdt_miscdev = {
> > > +	.minor		= WATCHDOG_MINOR,
> > > +	.name		= "da9052-wdt",
> > > +	.fops		= &da9052_wdt_fops,
> > > +};
> > > +
> > > +static int __devinit da9052_wdt_probe(struct platform_device *pdev)
> > > +{
> > > +	int ret;
> > > +
> > > +	da9052 = dev_get_drvdata(pdev->dev.parent);
> > > +
> > > +	ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
> > > +				DA9052_CONTROLD_TWDSCALE, 0);
> > > +	if (ret < 0) {
> > > +		dev_err(&pdev->dev, "Failed to disable watchdog bits, %d\n",
> > > +			ret);
> > > +		return ret;
> > > +	}
> > > +
> > > +	da9052_wdt_miscdev.parent = &pdev->dev;
> > > +
> > > +	ret = misc_register(&da9052_wdt_miscdev);
Could we move to watchdog registration instead of the misc one ?
> > > +
> > > +	return ret;
> > > +}
> > > +
> > > +static int __devexit da9052_wdt_remove(struct platform_device *dev)
> > > +{
> > > +	misc_deregister(&da9052_wdt_miscdev);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static struct platform_driver da9052_wdt_driver = {
> > > +	.probe = da9052_wdt_probe,
> > > +	.remove = __devexit_p(da9052_wdt_remove),
> > > +	.driver = {
> > > +		.name	= "da9052-watchdog",
> > > +		.owner	= THIS_MODULE,
> > > +	},
> > > +};
> > > +
> > > +module_platform_driver(da9052_wdt_driver);
> > > +
> > > +MODULE_AUTHOR("David Dajun Chen <dchen at diasemi.com>");
> > > +MODULE_DESCRIPTION("DA9052 SM Device Driver");
> > > +MODULE_LICENSE("GPL");
> > > +MODULE_ALIAS("platform:da9052-wdt");
> > > 
> > > 
> 
> 
> _______________________________________________
> linaro-dev mailing list
> linaro-dev at lists.linaro.org
> http://lists.linaro.org/mailman/listinfo/linaro-dev


[prev in list] [next in list] [prev in thread] [next in thread] 

Configure | About | News | Add a list | Sponsored by KoreLogic