From 8f8dc7bf3e0ab14d1ce1964dbe66ff8acf8779c6 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 31 Jan 2017 09:33:30 -0700 Subject: [PATCH] watchdog: ts72xx_wdt: convert driver to watchdog core Cleanup this driver and convert it to use the watchdog framework API. Signed-off-by: H Hartley Sweeten Cc: Mika Westerberg [groeck: Dropped initialization of static variable] Signed-off-by: Guenter Roeck --- drivers/watchdog/ts72xx_wdt.c | 471 ++++++++-------------------------- 1 file changed, 101 insertions(+), 370 deletions(-) diff --git a/drivers/watchdog/ts72xx_wdt.c b/drivers/watchdog/ts72xx_wdt.c index 4b541934b6c5..17c25daebcce 100644 --- a/drivers/watchdog/ts72xx_wdt.c +++ b/drivers/watchdog/ts72xx_wdt.c @@ -13,428 +13,159 @@ * warranty of any kind, whether express or implied. */ -#include -#include -#include -#include -#include -#include #include -#include +#include #include -#include +#include -#define TS72XX_WDT_FEED_VAL 0x05 -#define TS72XX_WDT_DEFAULT_TIMEOUT 8 +#define TS72XX_WDT_DEFAULT_TIMEOUT 30 -static int timeout = TS72XX_WDT_DEFAULT_TIMEOUT; +static int timeout; module_param(timeout, int, 0); -MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. " - "(1 <= timeout <= 8, default=" - __MODULE_STRING(TS72XX_WDT_DEFAULT_TIMEOUT) - ")"); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds."); static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); -/** - * struct ts72xx_wdt - watchdog control structure - * @lock: lock that protects this structure - * @regval: watchdog timeout value suitable for control register - * @flags: flags controlling watchdog device state - * @control_reg: watchdog control register - * @feed_reg: watchdog feed register - * @pdev: back pointer to platform dev - */ -struct ts72xx_wdt { - struct mutex lock; - int regval; +/* priv->control_reg */ +#define TS72XX_WDT_CTRL_DISABLE 0x00 +#define TS72XX_WDT_CTRL_250MS 0x01 +#define TS72XX_WDT_CTRL_500MS 0x02 +#define TS72XX_WDT_CTRL_1SEC 0x03 +#define TS72XX_WDT_CTRL_RESERVED 0x04 +#define TS72XX_WDT_CTRL_2SEC 0x05 +#define TS72XX_WDT_CTRL_4SEC 0x06 +#define TS72XX_WDT_CTRL_8SEC 0x07 -#define TS72XX_WDT_BUSY_FLAG 1 -#define TS72XX_WDT_EXPECT_CLOSE_FLAG 2 - int flags; +/* priv->feed_reg */ +#define TS72XX_WDT_FEED_VAL 0x05 +struct ts72xx_wdt_priv { void __iomem *control_reg; void __iomem *feed_reg; - - struct platform_device *pdev; + struct watchdog_device wdd; + unsigned char regval; }; -static struct platform_device *ts72xx_wdt_pdev; - -/* - * TS-72xx Watchdog supports following timeouts (value written - * to control register): - * value description - * ------------------------- - * 0x00 watchdog disabled - * 0x01 250ms - * 0x02 500ms - * 0x03 1s - * 0x04 reserved - * 0x05 2s - * 0x06 4s - * 0x07 8s - * - * Timeouts below 1s are not very usable so we don't - * allow them at all. - * - * We provide two functions that convert between these: - * timeout_to_regval() and regval_to_timeout(). - */ -static const struct { - int timeout; - int regval; -} ts72xx_wdt_map[] = { - { 1, 3 }, - { 2, 5 }, - { 4, 6 }, - { 8, 7 }, -}; - -/** - * timeout_to_regval() - converts given timeout to control register value - * @new_timeout: timeout in seconds to be converted - * - * Function converts given @new_timeout into valid value that can - * be programmed into watchdog control register. When conversion is - * not possible, function returns %-EINVAL. - */ -static int timeout_to_regval(int new_timeout) +static int ts72xx_wdt_start(struct watchdog_device *wdd) { - int i; + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); - /* first limit it to 1 - 8 seconds */ - new_timeout = clamp_val(new_timeout, 1, 8); + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + writeb(priv->regval, priv->control_reg); - for (i = 0; i < ARRAY_SIZE(ts72xx_wdt_map); i++) { - if (ts72xx_wdt_map[i].timeout >= new_timeout) - return ts72xx_wdt_map[i].regval; - } - - return -EINVAL; -} - -/** - * regval_to_timeout() - converts control register value to timeout - * @regval: control register value to be converted - * - * Function converts given @regval to timeout in seconds (1, 2, 4 or 8). - * If @regval cannot be converted, function returns %-EINVAL. - */ -static int regval_to_timeout(int regval) -{ - int i; - - for (i = 0; i < ARRAY_SIZE(ts72xx_wdt_map); i++) { - if (ts72xx_wdt_map[i].regval == regval) - return ts72xx_wdt_map[i].timeout; - } - - return -EINVAL; -} - -/** - * ts72xx_wdt_kick() - kick the watchdog - * @wdt: watchdog to be kicked - * - * Called with @wdt->lock held. - */ -static inline void ts72xx_wdt_kick(struct ts72xx_wdt *wdt) -{ - __raw_writeb(TS72XX_WDT_FEED_VAL, wdt->feed_reg); -} - -/** - * ts72xx_wdt_start() - starts the watchdog timer - * @wdt: watchdog to be started - * - * This function programs timeout to watchdog timer - * and starts it. - * - * Called with @wdt->lock held. - */ -static void ts72xx_wdt_start(struct ts72xx_wdt *wdt) -{ - /* - * To program the wdt, it first must be "fed" and - * only after that (within 30 usecs) the configuration - * can be changed. - */ - ts72xx_wdt_kick(wdt); - __raw_writeb((u8)wdt->regval, wdt->control_reg); -} - -/** - * ts72xx_wdt_stop() - stops the watchdog timer - * @wdt: watchdog to be stopped - * - * Called with @wdt->lock held. - */ -static void ts72xx_wdt_stop(struct ts72xx_wdt *wdt) -{ - ts72xx_wdt_kick(wdt); - __raw_writeb(0, wdt->control_reg); -} - -static int ts72xx_wdt_open(struct inode *inode, struct file *file) -{ - struct ts72xx_wdt *wdt = platform_get_drvdata(ts72xx_wdt_pdev); - int regval; - - /* - * Try to convert default timeout to valid register - * value first. - */ - regval = timeout_to_regval(timeout); - if (regval < 0) { - dev_err(&wdt->pdev->dev, - "failed to convert timeout (%d) to register value\n", - timeout); - return regval; - } - - if (mutex_lock_interruptible(&wdt->lock)) - return -ERESTARTSYS; - - if ((wdt->flags & TS72XX_WDT_BUSY_FLAG) != 0) { - mutex_unlock(&wdt->lock); - return -EBUSY; - } - - wdt->flags = TS72XX_WDT_BUSY_FLAG; - wdt->regval = regval; - file->private_data = wdt; - - ts72xx_wdt_start(wdt); - - mutex_unlock(&wdt->lock); - return nonseekable_open(inode, file); -} - -static int ts72xx_wdt_release(struct inode *inode, struct file *file) -{ - struct ts72xx_wdt *wdt = file->private_data; - - if (mutex_lock_interruptible(&wdt->lock)) - return -ERESTARTSYS; - - if ((wdt->flags & TS72XX_WDT_EXPECT_CLOSE_FLAG) != 0) { - ts72xx_wdt_stop(wdt); - } else { - dev_warn(&wdt->pdev->dev, - "TS-72XX WDT device closed unexpectly. " - "Watchdog timer will not stop!\n"); - /* - * Kick it one more time, to give userland some time - * to recover (for example, respawning the kicker - * daemon). - */ - ts72xx_wdt_kick(wdt); - } - - wdt->flags = 0; - - mutex_unlock(&wdt->lock); return 0; } -static ssize_t ts72xx_wdt_write(struct file *file, - const char __user *data, - size_t len, - loff_t *ppos) +static int ts72xx_wdt_stop(struct watchdog_device *wdd) { - struct ts72xx_wdt *wdt = file->private_data; + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); - if (!len) - return 0; + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + writeb(TS72XX_WDT_CTRL_DISABLE, priv->control_reg); - if (mutex_lock_interruptible(&wdt->lock)) - return -ERESTARTSYS; - - ts72xx_wdt_kick(wdt); - - /* - * Support for magic character closing. User process - * writes 'V' into the device, just before it is closed. - * This means that we know that the wdt timer can be - * stopped after user closes the device. - */ - if (!nowayout) { - int i; - - for (i = 0; i < len; i++) { - char c; - - /* In case it was set long ago */ - wdt->flags &= ~TS72XX_WDT_EXPECT_CLOSE_FLAG; - - if (get_user(c, data + i)) { - mutex_unlock(&wdt->lock); - return -EFAULT; - } - if (c == 'V') { - wdt->flags |= TS72XX_WDT_EXPECT_CLOSE_FLAG; - break; - } - } - } - - mutex_unlock(&wdt->lock); - return len; + return 0; } -static const struct watchdog_info winfo = { - .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | +static int ts72xx_wdt_ping(struct watchdog_device *wdd) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + + return 0; +} + +static int ts72xx_wdt_settimeout(struct watchdog_device *wdd, unsigned int to) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + if (to == 1) { + priv->regval = TS72XX_WDT_CTRL_1SEC; + } else if (to == 2) { + priv->regval = TS72XX_WDT_CTRL_2SEC; + } else if (to <= 4) { + priv->regval = TS72XX_WDT_CTRL_4SEC; + to = 4; + } else { + priv->regval = TS72XX_WDT_CTRL_8SEC; + if (to <= 8) + to = 8; + } + + wdd->timeout = to; + + if (watchdog_active(wdd)) { + ts72xx_wdt_stop(wdd); + ts72xx_wdt_start(wdd); + } + + return 0; +} + +static const struct watchdog_info ts72xx_wdt_ident = { + .options = WDIOF_KEEPALIVEPING | + WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, .firmware_version = 1, .identity = "TS-72XX WDT", }; -static long ts72xx_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) -{ - struct ts72xx_wdt *wdt = file->private_data; - void __user *argp = (void __user *)arg; - int __user *p = (int __user *)argp; - int error = 0; - - if (mutex_lock_interruptible(&wdt->lock)) - return -ERESTARTSYS; - - switch (cmd) { - case WDIOC_GETSUPPORT: - if (copy_to_user(argp, &winfo, sizeof(winfo))) - error = -EFAULT; - break; - - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - error = put_user(0, p); - break; - - case WDIOC_KEEPALIVE: - ts72xx_wdt_kick(wdt); - break; - - case WDIOC_SETOPTIONS: { - int options; - - error = get_user(options, p); - if (error) - break; - - error = -EINVAL; - - if ((options & WDIOS_DISABLECARD) != 0) { - ts72xx_wdt_stop(wdt); - error = 0; - } - if ((options & WDIOS_ENABLECARD) != 0) { - ts72xx_wdt_start(wdt); - error = 0; - } - - break; - } - - case WDIOC_SETTIMEOUT: { - int new_timeout; - int regval; - - error = get_user(new_timeout, p); - if (error) - break; - - regval = timeout_to_regval(new_timeout); - if (regval < 0) { - error = regval; - break; - } - ts72xx_wdt_stop(wdt); - wdt->regval = regval; - ts72xx_wdt_start(wdt); - - /*FALLTHROUGH*/ - } - - case WDIOC_GETTIMEOUT: - error = put_user(regval_to_timeout(wdt->regval), p); - break; - - default: - error = -ENOTTY; - break; - } - - mutex_unlock(&wdt->lock); - return error; -} - -static const struct file_operations ts72xx_wdt_fops = { +static struct watchdog_ops ts72xx_wdt_ops = { .owner = THIS_MODULE, - .llseek = no_llseek, - .open = ts72xx_wdt_open, - .release = ts72xx_wdt_release, - .write = ts72xx_wdt_write, - .unlocked_ioctl = ts72xx_wdt_ioctl, -}; - -static struct miscdevice ts72xx_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &ts72xx_wdt_fops, + .start = ts72xx_wdt_start, + .stop = ts72xx_wdt_stop, + .ping = ts72xx_wdt_ping, + .set_timeout = ts72xx_wdt_settimeout, }; static int ts72xx_wdt_probe(struct platform_device *pdev) { - struct ts72xx_wdt *wdt; - struct resource *r1, *r2; - int error = 0; + struct ts72xx_wdt_priv *priv; + struct watchdog_device *wdd; + struct resource *res; + int ret; - wdt = devm_kzalloc(&pdev->dev, sizeof(struct ts72xx_wdt), GFP_KERNEL); - if (!wdt) + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) return -ENOMEM; - r1 = platform_get_resource(pdev, IORESOURCE_MEM, 0); - wdt->control_reg = devm_ioremap_resource(&pdev->dev, r1); - if (IS_ERR(wdt->control_reg)) - return PTR_ERR(wdt->control_reg); + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->control_reg = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->control_reg)) + return PTR_ERR(priv->control_reg); - r2 = platform_get_resource(pdev, IORESOURCE_MEM, 1); - wdt->feed_reg = devm_ioremap_resource(&pdev->dev, r2); - if (IS_ERR(wdt->feed_reg)) - return PTR_ERR(wdt->feed_reg); + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + priv->feed_reg = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->feed_reg)) + return PTR_ERR(priv->feed_reg); - platform_set_drvdata(pdev, wdt); - ts72xx_wdt_pdev = pdev; - wdt->pdev = pdev; - mutex_init(&wdt->lock); + wdd = &priv->wdd; + wdd->info = &ts72xx_wdt_ident; + wdd->ops = &ts72xx_wdt_ops; + wdd->min_timeout = 1; + wdd->max_hw_heartbeat_ms = 8000; + wdd->parent = &pdev->dev; - /* make sure that the watchdog is disabled */ - ts72xx_wdt_stop(wdt); + watchdog_set_nowayout(wdd, nowayout); - error = misc_register(&ts72xx_wdt_miscdev); - if (error) { - dev_err(&pdev->dev, "failed to register miscdev\n"); - return error; - } + wdd->timeout = TS72XX_WDT_DEFAULT_TIMEOUT; + watchdog_init_timeout(wdd, timeout, &pdev->dev); + + watchdog_set_drvdata(wdd, priv); + + ret = devm_watchdog_register_device(&pdev->dev, wdd); + if (ret) + return ret; dev_info(&pdev->dev, "TS-72xx Watchdog driver\n"); return 0; } -static int ts72xx_wdt_remove(struct platform_device *pdev) -{ - misc_deregister(&ts72xx_wdt_miscdev); - return 0; -} - static struct platform_driver ts72xx_wdt_driver = { .probe = ts72xx_wdt_probe, - .remove = ts72xx_wdt_remove, .driver = { .name = "ts72xx-wdt", },