Messages in this thread |  | | Date | Mon, 18 Nov 2013 21:12:41 -0800 | From | Guenter Roeck <> | Subject | Re: [PATCH 1/6] watchdog: davinci: change driver to use WDT core |
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On 11/18/2013 09:18 AM, Ivan Khoronzhuk wrote: > To reduce code duplicate and increase code readability use WDT core > code to handle WDT interface. > > Remove io_lock as the WDT core uses mutex to lock each wdt device. > Remove wdt_state as the WDT core track state with its own variable. > > The watchdog_init_timeout() can read timeout value from timeout-sec > property if the passed value is out of bounds. The heartbeat is > initialized in next way. If heartbeat is not set thought module > parameter, try to read it's value from WDT node timeout-sec property. > If node has no one, use default value. > > The heartbeat is hold in wdd->timeout by WDT core, so use it in > order to set timeout period. > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> > Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> > --- > drivers/watchdog/Kconfig | 2 + > drivers/watchdog/davinci_wdt.c | 152 ++++++++++------------------------------ > 2 files changed, 39 insertions(+), 115 deletions(-) > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index d1d53f3..d7db13d 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -271,6 +271,8 @@ config IOP_WATCHDOG > config DAVINCI_WATCHDOG > tristate "DaVinci watchdog" > depends on ARCH_DAVINCI > + select WATCHDOG_CORE > + select WATCHDOG_NOWAYOUT
Is this mandatory, ie is it correct that the watchdog can not be stopped once started ?
Assuming it is,
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
> help > Say Y here if to include support for the watchdog timer > in the DaVinci DM644x/DM646x processors. > diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c > index bead774..cb9e8c5 100644 > --- a/drivers/watchdog/davinci_wdt.c > +++ b/drivers/watchdog/davinci_wdt.c > @@ -3,7 +3,7 @@ > * > * Watchdog driver for DaVinci DM644x/DM646x processors > * > - * Copyright (C) 2006 Texas Instruments. > + * Copyright (C) 2006-2013 Texas Instruments. > * > * 2007 (c) MontaVista Software, Inc. This file is licensed under > * the terms of the GNU General Public License version 2. This program > @@ -15,18 +15,12 @@ > #include <linux/moduleparam.h> > #include <linux/types.h> > #include <linux/kernel.h> > -#include <linux/fs.h> > -#include <linux/miscdevice.h> > #include <linux/watchdog.h> > #include <linux/init.h> > -#include <linux/bitops.h> > #include <linux/platform_device.h> > -#include <linux/spinlock.h> > -#include <linux/uaccess.h> > #include <linux/io.h> > #include <linux/device.h> > #include <linux/clk.h> > -#include <linux/slab.h> > #include <linux/err.h> > > #define MODULE_NAME "DAVINCI-WDT: " > @@ -61,31 +55,12 @@ > #define WDKEY_SEQ0 (0xa5c6 << 16) > #define WDKEY_SEQ1 (0xda7e << 16) > > -static int heartbeat = DEFAULT_HEARTBEAT; > - > -static DEFINE_SPINLOCK(io_lock); > -static unsigned long wdt_status; > -#define WDT_IN_USE 0 > -#define WDT_OK_TO_CLOSE 1 > -#define WDT_REGION_INITED 2 > -#define WDT_DEVICE_INITED 3 > - > +static int heartbeat; > static void __iomem *wdt_base; > struct clk *wdt_clk; > +static struct watchdog_device wdt_wdd; > > -static void wdt_service(void) > -{ > - spin_lock(&io_lock); > - > - /* put watchdog in service state */ > - iowrite32(WDKEY_SEQ0, wdt_base + WDTCR); > - /* put watchdog in active state */ > - iowrite32(WDKEY_SEQ1, wdt_base + WDTCR); > - > - spin_unlock(&io_lock); > -} > - > -static void wdt_enable(void) > +static int davinci_wdt_start(struct watchdog_device *wdd) > { > u32 tgcr; > u32 timer_margin; > @@ -93,8 +68,6 @@ static void wdt_enable(void) > > wdt_freq = clk_get_rate(wdt_clk); > > - spin_lock(&io_lock); > - > /* disable, internal clock source */ > iowrite32(0, wdt_base + TCR); > /* reset timer, set mode to 64-bit watchdog, and unreset */ > @@ -105,9 +78,9 @@ static void wdt_enable(void) > iowrite32(0, wdt_base + TIM12); > iowrite32(0, wdt_base + TIM34); > /* set timeout period */ > - timer_margin = (((u64)heartbeat * wdt_freq) & 0xffffffff); > + timer_margin = (((u64)wdd->timeout * wdt_freq) & 0xffffffff); > iowrite32(timer_margin, wdt_base + PRD12); > - timer_margin = (((u64)heartbeat * wdt_freq) >> 32); > + timer_margin = (((u64)wdd->timeout * wdt_freq) >> 32); > iowrite32(timer_margin, wdt_base + PRD34); > /* enable run continuously */ > iowrite32(ENAMODE12_PERIODIC, wdt_base + TCR); > @@ -119,84 +92,28 @@ static void wdt_enable(void) > iowrite32(WDKEY_SEQ0 | WDEN, wdt_base + WDTCR); > /* put watchdog in active state */ > iowrite32(WDKEY_SEQ1 | WDEN, wdt_base + WDTCR); > - > - spin_unlock(&io_lock); > -} > - > -static int davinci_wdt_open(struct inode *inode, struct file *file) > -{ > - if (test_and_set_bit(WDT_IN_USE, &wdt_status)) > - return -EBUSY; > - > - wdt_enable(); > - > - return nonseekable_open(inode, file); > + return 0; > } > > -static ssize_t > -davinci_wdt_write(struct file *file, const char *data, size_t len, > - loff_t *ppos) > +static int davinci_wdt_ping(struct watchdog_device *wdd) > { > - if (len) > - wdt_service(); > - > - return len; > + /* put watchdog in service state */ > + iowrite32(WDKEY_SEQ0, wdt_base + WDTCR); > + /* put watchdog in active state */ > + iowrite32(WDKEY_SEQ1, wdt_base + WDTCR); > + return 0; > } > > -static const struct watchdog_info ident = { > +static const struct watchdog_info davinci_wdt_info = { > .options = WDIOF_KEEPALIVEPING, > .identity = "DaVinci Watchdog", > }; > > -static long davinci_wdt_ioctl(struct file *file, > - unsigned int cmd, unsigned long arg) > -{ > - int ret = -ENOTTY; > - > - switch (cmd) { > - case WDIOC_GETSUPPORT: > - ret = copy_to_user((struct watchdog_info *)arg, &ident, > - sizeof(ident)) ? -EFAULT : 0; > - break; > - > - case WDIOC_GETSTATUS: > - case WDIOC_GETBOOTSTATUS: > - ret = put_user(0, (int *)arg); > - break; > - > - case WDIOC_KEEPALIVE: > - wdt_service(); > - ret = 0; > - break; > - > - case WDIOC_GETTIMEOUT: > - ret = put_user(heartbeat, (int *)arg); > - break; > - } > - return ret; > -} > - > -static int davinci_wdt_release(struct inode *inode, struct file *file) > -{ > - wdt_service(); > - clear_bit(WDT_IN_USE, &wdt_status); > - > - return 0; > -} > - > -static const struct file_operations davinci_wdt_fops = { > - .owner = THIS_MODULE, > - .llseek = no_llseek, > - .write = davinci_wdt_write, > - .unlocked_ioctl = davinci_wdt_ioctl, > - .open = davinci_wdt_open, > - .release = davinci_wdt_release, > -}; > - > -static struct miscdevice davinci_wdt_miscdev = { > - .minor = WATCHDOG_MINOR, > - .name = "watchdog", > - .fops = &davinci_wdt_fops, > +static const struct watchdog_ops davinci_wdt_ops = { > + .owner = THIS_MODULE, > + .start = davinci_wdt_start, > + .stop = davinci_wdt_ping, > + .ping = davinci_wdt_ping, > }; > > static int davinci_wdt_probe(struct platform_device *pdev) > @@ -204,6 +121,7 @@ static int davinci_wdt_probe(struct platform_device *pdev) > int ret = 0; > struct device *dev = &pdev->dev; > struct resource *wdt_mem; > + struct watchdog_device *wdd; > > wdt_clk = devm_clk_get(dev, NULL); > if (WARN_ON(IS_ERR(wdt_clk))) > @@ -211,29 +129,34 @@ static int davinci_wdt_probe(struct platform_device *pdev) > > clk_prepare_enable(wdt_clk); > > - if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT) > - heartbeat = DEFAULT_HEARTBEAT; > + wdd = &wdt_wdd; > + wdd->info = &davinci_wdt_info; > + wdd->ops = &davinci_wdt_ops; > + wdd->min_timeout = 1; > + wdd->max_timeout = MAX_HEARTBEAT; > + wdd->timeout = DEFAULT_HEARTBEAT; > + > + watchdog_init_timeout(wdd, heartbeat, dev); > + > + dev_info(dev, "heartbeat %d sec\n", wdd->timeout); > > - dev_info(dev, "heartbeat %d sec\n", heartbeat); > + watchdog_set_nowayout(wdd, WATCHDOG_NOWAYOUT); > > wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > wdt_base = devm_ioremap_resource(dev, wdt_mem); > if (IS_ERR(wdt_base)) > return PTR_ERR(wdt_base); > > - ret = misc_register(&davinci_wdt_miscdev); > - if (ret < 0) { > - dev_err(dev, "cannot register misc device\n"); > - } else { > - set_bit(WDT_DEVICE_INITED, &wdt_status); > - } > + ret = watchdog_register_device(wdd); > + if (ret < 0) > + dev_err(dev, "cannot register watchdog device\n"); > > return ret; > } > > static int davinci_wdt_remove(struct platform_device *pdev) > { > - misc_deregister(&davinci_wdt_miscdev); > + watchdog_unregister_device(&wdt_wdd); > clk_disable_unprepare(wdt_clk); > > return 0; > @@ -247,7 +170,7 @@ MODULE_DEVICE_TABLE(of, davinci_wdt_of_match); > > static struct platform_driver platform_wdt_driver = { > .driver = { > - .name = "watchdog", > + .name = "davinci-wdt", > .owner = THIS_MODULE, > .of_match_table = davinci_wdt_of_match, > }, > @@ -267,5 +190,4 @@ MODULE_PARM_DESC(heartbeat, > __MODULE_STRING(DEFAULT_HEARTBEAT)); > > MODULE_LICENSE("GPL"); > -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); > -MODULE_ALIAS("platform:watchdog"); > +MODULE_ALIAS("platform:davinci-wdt"); >
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