From mboxrd@z Thu Jan 1 00:00:00 1970 From: agust@denx.de (Anatolij Gustschin) Date: Wed, 7 May 2014 01:33:02 +0200 Subject: [PATCH v2] watchdog: imx2_wdt: convert to watchdog core api In-Reply-To: <1397199434-6551-1-git-send-email-agust@denx.de> References: <1397199434-6551-1-git-send-email-agust@denx.de> Message-ID: <20140507013302.2f0ef27c@crub> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, 11 Apr 2014 08:57:14 +0200 Anatolij Gustschin wrote: > Convert the imx2_wdt driver to the new watchdog core api. > > Signed-off-by: Anatolij Gustschin > Cc: Wolfram Sang > Cc: Wim Van Sebroeck Ping. Will this patch be queued for next? Thanks, Anatolij > --- > NOTE: This patch applies on top of the imx2_wdt regmap-mmio support > patch series http://comments.gmane.org/gmane.linux.kernel/1677735 > > Changes since first version: > - simplify return in imx2_wdt_is_running() > - fix "WARNING: quoted string split across lines" > > drivers/watchdog/Kconfig | 1 + > drivers/watchdog/imx2_wdt.c | 292 ++++++++++++++++++------------------------- > 2 files changed, 123 insertions(+), 170 deletions(-) > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index f2a15f4..5e78c77c 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -379,6 +379,7 @@ config IMX2_WDT > tristate "IMX2+ Watchdog" > depends on ARCH_MXC > select REGMAP_MMIO > + select WATCHDOG_CORE > help > This is the driver for the hardware watchdog > on the Freescale IMX2 and later processors. > diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c > index 76fa724..9d4874f 100644 > --- a/drivers/watchdog/imx2_wdt.c > +++ b/drivers/watchdog/imx2_wdt.c > @@ -22,18 +22,15 @@ > */ > > #include > -#include > #include > #include > #include > #include > -#include > #include > #include > #include > #include > #include > -#include > #include > > #define DRIVER_NAME "imx2-wdt" > @@ -56,19 +53,12 @@ > > #define WDOG_SEC_TO_COUNT(s) ((s * 2 - 1) << 8) > > -#define IMX2_WDT_STATUS_OPEN 0 > -#define IMX2_WDT_STATUS_STARTED 1 > -#define IMX2_WDT_EXPECT_CLOSE 2 > - > -static struct { > +struct imx2_wdt_device { > struct clk *clk; > struct regmap *regmap; > - unsigned timeout; > - unsigned long status; > struct timer_list timer; /* Pings the watchdog when closed */ > -} imx2_wdt; > - > -static struct miscdevice imx2_wdt_miscdev; > + struct watchdog_device wdog; > +}; > > static bool nowayout = WATCHDOG_NOWAYOUT; > module_param(nowayout, bool, 0); > @@ -86,11 +76,12 @@ static const struct watchdog_info imx2_wdt_info = { > .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, > }; > > -static inline void imx2_wdt_setup(void) > +static inline void imx2_wdt_setup(struct watchdog_device *wdog) > { > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > u32 val; > > - regmap_read(imx2_wdt.regmap, IMX2_WDT_WCR, &val); > + regmap_read(wdev->regmap, IMX2_WDT_WCR, &val); > > /* Suspend timer in low power mode, write once-only */ > val |= IMX2_WDT_WCR_WDZST; > @@ -101,157 +92,93 @@ static inline void imx2_wdt_setup(void) > /* Keep Watchdog Disabled */ > val &= ~IMX2_WDT_WCR_WDE; > /* Set the watchdog's Time-Out value */ > - val |= WDOG_SEC_TO_COUNT(imx2_wdt.timeout); > + val |= WDOG_SEC_TO_COUNT(wdog->timeout); > > - regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val); > + regmap_write(wdev->regmap, IMX2_WDT_WCR, val); > > /* enable the watchdog */ > val |= IMX2_WDT_WCR_WDE; > - regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val); > + regmap_write(wdev->regmap, IMX2_WDT_WCR, val); > } > > -static inline void imx2_wdt_ping(void) > +static inline bool imx2_wdt_is_running(struct imx2_wdt_device *wdev) > { > - regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1); > - regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2); > -} > + u32 val; > > -static void imx2_wdt_timer_ping(unsigned long arg) > -{ > - /* ping it every imx2_wdt.timeout / 2 seconds to prevent reboot */ > - imx2_wdt_ping(); > - mod_timer(&imx2_wdt.timer, jiffies + imx2_wdt.timeout * HZ / 2); > + regmap_read(wdev->regmap, IMX2_WDT_WCR, &val); > + > + return val & IMX2_WDT_WCR_WDE; > } > > -static void imx2_wdt_start(void) > +static int imx2_wdt_ping(struct watchdog_device *wdog) > { > - if (!test_and_set_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { > - /* at our first start we enable clock and do initialisations */ > - clk_prepare_enable(imx2_wdt.clk); > - > - imx2_wdt_setup(); > - } else /* delete the timer that pings the watchdog after close */ > - del_timer_sync(&imx2_wdt.timer); > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > > - /* Watchdog is enabled - time to reload the timeout value */ > - imx2_wdt_ping(); > + regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1); > + regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2); > + return 0; > } > > -static void imx2_wdt_stop(void) > +static void imx2_wdt_timer_ping(unsigned long arg) > { > - /* we don't need a clk_disable, it cannot be disabled once started. > - * We use a timer to ping the watchdog while /dev/watchdog is closed */ > - imx2_wdt_timer_ping(0); > + struct watchdog_device *wdog = (struct watchdog_device *)arg; > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > + > + /* ping it every wdog->timeout / 2 seconds to prevent reboot */ > + imx2_wdt_ping(wdog); > + mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2); > } > > -static void imx2_wdt_set_timeout(int new_timeout) > +static int imx2_wdt_set_timeout(struct watchdog_device *wdog, > + unsigned int new_timeout) > { > - regmap_update_bits(imx2_wdt.regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT, > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > + > + regmap_update_bits(wdev->regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT, > WDOG_SEC_TO_COUNT(new_timeout)); > + return 0; > } > > -static int imx2_wdt_open(struct inode *inode, struct file *file) > +static int imx2_wdt_start(struct watchdog_device *wdog) > { > - if (test_and_set_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status)) > - return -EBUSY; > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > > - imx2_wdt_start(); > - return nonseekable_open(inode, file); > + if (imx2_wdt_is_running(wdev)) { > + /* delete the timer that pings the watchdog after close */ > + del_timer_sync(&wdev->timer); > + imx2_wdt_set_timeout(wdog, wdog->timeout); > + } else > + imx2_wdt_setup(wdog); > + > + return imx2_wdt_ping(wdog); > } > > -static int imx2_wdt_close(struct inode *inode, struct file *file) > +static int imx2_wdt_stop(struct watchdog_device *wdog) > { > - if (test_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status) && !nowayout) > - imx2_wdt_stop(); > - else { > - dev_crit(imx2_wdt_miscdev.parent, > - "Unexpected close: Expect reboot!\n"); > - imx2_wdt_ping(); > - } > - > - clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); > - clear_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status); > + /* > + * We don't need a clk_disable, it cannot be disabled once started. > + * We use a timer to ping the watchdog while /dev/watchdog is closed > + */ > + imx2_wdt_timer_ping((unsigned long)wdog); > return 0; > } > > -static long imx2_wdt_ioctl(struct file *file, unsigned int cmd, > - unsigned long arg) > +static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog) > { > - void __user *argp = (void __user *)arg; > - int __user *p = argp; > - int new_value; > - u32 val; > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > > - switch (cmd) { > - case WDIOC_GETSUPPORT: > - return copy_to_user(argp, &imx2_wdt_info, > - sizeof(struct watchdog_info)) ? -EFAULT : 0; > - > - case WDIOC_GETSTATUS: > - return put_user(0, p); > - > - case WDIOC_GETBOOTSTATUS: > - regmap_read(imx2_wdt.regmap, IMX2_WDT_WRSR, &val); > - new_value = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0; > - return put_user(new_value, p); > - > - case WDIOC_KEEPALIVE: > - imx2_wdt_ping(); > - return 0; > - > - case WDIOC_SETTIMEOUT: > - if (get_user(new_value, p)) > - return -EFAULT; > - if ((new_value < 1) || (new_value > IMX2_WDT_MAX_TIME)) > - return -EINVAL; > - imx2_wdt_set_timeout(new_value); > - imx2_wdt.timeout = new_value; > - imx2_wdt_ping(); > - > - /* Fallthrough to return current value */ > - case WDIOC_GETTIMEOUT: > - return put_user(imx2_wdt.timeout, p); > - > - default: > - return -ENOTTY; > + if (imx2_wdt_is_running(wdev)) { > + imx2_wdt_set_timeout(wdog, wdog->timeout); > + imx2_wdt_timer_ping((unsigned long)wdog); > } > } > > -static ssize_t imx2_wdt_write(struct file *file, const char __user *data, > - size_t len, loff_t *ppos) > -{ > - size_t i; > - char c; > - > - if (len == 0) /* Can we see this even ? */ > - return 0; > - > - clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); > - /* scan to see whether or not we got the magic character */ > - for (i = 0; i != len; i++) { > - if (get_user(c, data + i)) > - return -EFAULT; > - if (c == 'V') > - set_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); > - } > - > - imx2_wdt_ping(); > - return len; > -} > - > -static const struct file_operations imx2_wdt_fops = { > +static struct watchdog_ops imx2_wdt_ops = { > .owner = THIS_MODULE, > - .llseek = no_llseek, > - .unlocked_ioctl = imx2_wdt_ioctl, > - .open = imx2_wdt_open, > - .release = imx2_wdt_close, > - .write = imx2_wdt_write, > -}; > - > -static struct miscdevice imx2_wdt_miscdev = { > - .minor = WATCHDOG_MINOR, > - .name = "watchdog", > - .fops = &imx2_wdt_fops, > + .start = imx2_wdt_start, > + .stop = imx2_wdt_stop, > + .ping = imx2_wdt_ping, > + .set_timeout = imx2_wdt_set_timeout, > }; > > static struct regmap_config imx2_wdt_regmap_config = { > @@ -263,76 +190,101 @@ static struct regmap_config imx2_wdt_regmap_config = { > > static int __init imx2_wdt_probe(struct platform_device *pdev) > { > + struct imx2_wdt_device *wdev; > + struct watchdog_device *wdog; > struct resource *res; > void __iomem *base; > int ret; > + u32 val; > + > + wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL); > + if (!wdev) > + return -ENOMEM; > > res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > base = devm_ioremap_resource(&pdev->dev, res); > if (IS_ERR(base)) > return PTR_ERR(base); > > - imx2_wdt.regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, > - &imx2_wdt_regmap_config); > - if (IS_ERR(imx2_wdt.regmap)) { > + wdev->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, > + &imx2_wdt_regmap_config); > + if (IS_ERR(wdev->regmap)) { > dev_err(&pdev->dev, "regmap init failed\n"); > - return PTR_ERR(imx2_wdt.regmap); > + return PTR_ERR(wdev->regmap); > } > > - imx2_wdt.clk = devm_clk_get(&pdev->dev, NULL); > - if (IS_ERR(imx2_wdt.clk)) { > + wdev->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(wdev->clk)) { > dev_err(&pdev->dev, "can't get Watchdog clock\n"); > - return PTR_ERR(imx2_wdt.clk); > + return PTR_ERR(wdev->clk); > } > > - imx2_wdt.timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME); > - if (imx2_wdt.timeout != timeout) > - dev_warn(&pdev->dev, "Initial timeout out of range! " > - "Clamped from %u to %u\n", timeout, imx2_wdt.timeout); > + wdog = &wdev->wdog; > + wdog->info = &imx2_wdt_info; > + wdog->ops = &imx2_wdt_ops; > + wdog->min_timeout = 1; > + wdog->max_timeout = IMX2_WDT_MAX_TIME; > > - setup_timer(&imx2_wdt.timer, imx2_wdt_timer_ping, 0); > + clk_prepare_enable(wdev->clk); > > - imx2_wdt_miscdev.parent = &pdev->dev; > - ret = misc_register(&imx2_wdt_miscdev); > - if (ret) > - goto fail; > + regmap_read(wdev->regmap, IMX2_WDT_WRSR, &val); > + wdog->bootstatus = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0; > > - dev_info(&pdev->dev, > - "IMX2+ Watchdog Timer enabled. timeout=%ds (nowayout=%d)\n", > - imx2_wdt.timeout, nowayout); > - return 0; > + wdog->timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME); > + if (wdog->timeout != timeout) > + dev_warn(&pdev->dev, "Initial timeout out of range! Clamped from %u to %u\n", > + timeout, wdog->timeout); > + > + platform_set_drvdata(pdev, wdog); > + watchdog_set_drvdata(wdog, wdev); > + watchdog_set_nowayout(wdog, nowayout); > + watchdog_init_timeout(wdog, timeout, &pdev->dev); > + > + setup_timer(&wdev->timer, imx2_wdt_timer_ping, (unsigned long)wdog); > > -fail: > - imx2_wdt_miscdev.parent = NULL; > - return ret; > + imx2_wdt_ping_if_active(wdog); > + > + ret = watchdog_register_device(wdog); > + if (ret) { > + dev_err(&pdev->dev, "cannot register watchdog device\n"); > + return ret; > + } > + > + dev_info(&pdev->dev, "timeout %d sec (nowayout=%d)\n", > + wdog->timeout, nowayout); > + > + return 0; > } > > static int __exit imx2_wdt_remove(struct platform_device *pdev) > { > - misc_deregister(&imx2_wdt_miscdev); > + struct watchdog_device *wdog = platform_get_drvdata(pdev); > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > > - if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { > - del_timer_sync(&imx2_wdt.timer); > + watchdog_unregister_device(wdog); > > - dev_crit(imx2_wdt_miscdev.parent, > - "Device removed: Expect reboot!\n"); > + if (imx2_wdt_is_running(wdev)) { > + del_timer_sync(&wdev->timer); > + imx2_wdt_ping(wdog); > + dev_crit(&pdev->dev, "Device removed: Expect reboot!\n"); > } > - > - imx2_wdt_miscdev.parent = NULL; > return 0; > } > > static void imx2_wdt_shutdown(struct platform_device *pdev) > { > - if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { > - /* we are running, we need to delete the timer but will give > - * max timeout before reboot will take place */ > - del_timer_sync(&imx2_wdt.timer); > - imx2_wdt_set_timeout(IMX2_WDT_MAX_TIME); > - imx2_wdt_ping(); > - > - dev_crit(imx2_wdt_miscdev.parent, > - "Device shutdown: Expect reboot!\n"); > + struct watchdog_device *wdog = platform_get_drvdata(pdev); > + struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog); > + > + if (imx2_wdt_is_running(wdev)) { > + /* > + * We are running, we need to delete the timer but will > + * give max timeout before reboot will take place > + */ > + del_timer_sync(&wdev->timer); > + imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME); > + imx2_wdt_ping(wdog); > + dev_crit(&pdev->dev, "Device shutdown: Expect reboot!\n"); > } > } >