diff options
Diffstat (limited to 'drivers/watchdog/davinci_wdt.c')
-rw-r--r-- | drivers/watchdog/davinci_wdt.c | 221 |
1 files changed, 96 insertions, 125 deletions
diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c index 12591f6596ef..b1bae03742a9 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: " @@ -61,142 +55,103 @@ #define WDKEY_SEQ0 (0xa5c6 << 16) #define WDKEY_SEQ1 (0xda7e << 16) -static int heartbeat = DEFAULT_HEARTBEAT; +static int 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 void __iomem *wdt_base; -struct clk *wdt_clk; - -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); -} +/* + * struct to hold data for each WDT device + * @base - base io address of WD device + * @clk - source clock of WDT + * @wdd - hold watchdog device as is in WDT core + */ +struct davinci_wdt_device { + void __iomem *base; + struct clk *clk; + struct watchdog_device wdd; +}; -static void wdt_enable(void) +static int davinci_wdt_start(struct watchdog_device *wdd) { u32 tgcr; u32 timer_margin; unsigned long wdt_freq; + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); - wdt_freq = clk_get_rate(wdt_clk); - - spin_lock(&io_lock); + wdt_freq = clk_get_rate(davinci_wdt->clk); /* disable, internal clock source */ - iowrite32(0, wdt_base + TCR); + iowrite32(0, davinci_wdt->base + TCR); /* reset timer, set mode to 64-bit watchdog, and unreset */ - iowrite32(0, wdt_base + TGCR); + iowrite32(0, davinci_wdt->base + TGCR); tgcr = TIMMODE_64BIT_WDOG | TIM12RS_UNRESET | TIM34RS_UNRESET; - iowrite32(tgcr, wdt_base + TGCR); + iowrite32(tgcr, davinci_wdt->base + TGCR); /* clear counter regs */ - iowrite32(0, wdt_base + TIM12); - iowrite32(0, wdt_base + TIM34); + iowrite32(0, davinci_wdt->base + TIM12); + iowrite32(0, davinci_wdt->base + TIM34); /* set timeout period */ - timer_margin = (((u64)heartbeat * wdt_freq) & 0xffffffff); - iowrite32(timer_margin, wdt_base + PRD12); - timer_margin = (((u64)heartbeat * wdt_freq) >> 32); - iowrite32(timer_margin, wdt_base + PRD34); + timer_margin = (((u64)wdd->timeout * wdt_freq) & 0xffffffff); + iowrite32(timer_margin, davinci_wdt->base + PRD12); + timer_margin = (((u64)wdd->timeout * wdt_freq) >> 32); + iowrite32(timer_margin, davinci_wdt->base + PRD34); /* enable run continuously */ - iowrite32(ENAMODE12_PERIODIC, wdt_base + TCR); + iowrite32(ENAMODE12_PERIODIC, davinci_wdt->base + TCR); /* Once the WDT is in pre-active state write to * TIM12, TIM34, PRD12, PRD34, TCR, TGCR, WDTCR are * write protected (except for the WDKEY field) */ /* put watchdog in pre-active state */ - iowrite32(WDKEY_SEQ0 | WDEN, wdt_base + WDTCR); + iowrite32(WDKEY_SEQ0 | WDEN, davinci_wdt->base + WDTCR); /* put watchdog in active state */ - iowrite32(WDKEY_SEQ1 | WDEN, wdt_base + WDTCR); - - spin_unlock(&io_lock); + iowrite32(WDKEY_SEQ1 | WDEN, davinci_wdt->base + WDTCR); + return 0; } -static int davinci_wdt_open(struct inode *inode, struct file *file) +static int davinci_wdt_ping(struct watchdog_device *wdd) { - if (test_and_set_bit(WDT_IN_USE, &wdt_status)) - return -EBUSY; - - wdt_enable(); + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); - return nonseekable_open(inode, file); + /* put watchdog in service state */ + iowrite32(WDKEY_SEQ0, davinci_wdt->base + WDTCR); + /* put watchdog in active state */ + iowrite32(WDKEY_SEQ1, davinci_wdt->base + WDTCR); + return 0; } -static ssize_t -davinci_wdt_write(struct file *file, const char *data, size_t len, - loff_t *ppos) +static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd) { - if (len) - wdt_service(); + u64 timer_counter; + unsigned long freq; + u32 val; + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); - return len; -} + /* if timeout has occured then return 0 */ + val = ioread32(davinci_wdt->base + WDTCR); + if (val & WDFLAG) + return 0; -static const struct watchdog_info ident = { - .options = WDIOF_KEEPALIVEPING, - .identity = "DaVinci Watchdog", -}; + freq = clk_get_rate(davinci_wdt->clk); -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; -} + if (!freq) + return 0; -static int davinci_wdt_release(struct inode *inode, struct file *file) -{ - wdt_service(); - clear_bit(WDT_IN_USE, &wdt_status); + timer_counter = ioread32(davinci_wdt->base + TIM12); + timer_counter |= ((u64)ioread32(davinci_wdt->base + TIM34) << 32); - return 0; + do_div(timer_counter, freq); + + return wdd->timeout - timer_counter; } -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 const struct watchdog_info davinci_wdt_info = { + .options = WDIOF_KEEPALIVEPING, + .identity = "DaVinci/Keystone Watchdog", }; -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, + .get_timeleft = davinci_wdt_get_timeleft, }; static int davinci_wdt_probe(struct platform_device *pdev) @@ -204,37 +159,53 @@ 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; + struct davinci_wdt_device *davinci_wdt; + + davinci_wdt = devm_kzalloc(dev, sizeof(*davinci_wdt), GFP_KERNEL); + if (!davinci_wdt) + return -ENOMEM; - wdt_clk = devm_clk_get(dev, NULL); - if (WARN_ON(IS_ERR(wdt_clk))) - return PTR_ERR(wdt_clk); + davinci_wdt->clk = devm_clk_get(dev, NULL); + if (WARN_ON(IS_ERR(davinci_wdt->clk))) + return PTR_ERR(davinci_wdt->clk); - clk_prepare_enable(wdt_clk); + clk_prepare_enable(davinci_wdt->clk); - if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT) - heartbeat = DEFAULT_HEARTBEAT; + platform_set_drvdata(pdev, davinci_wdt); - dev_info(dev, "heartbeat %d sec\n", heartbeat); + wdd = &davinci_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); + + watchdog_set_drvdata(wdd, davinci_wdt); + watchdog_set_nowayout(wdd, 1); 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); + davinci_wdt->base = devm_ioremap_resource(dev, wdt_mem); + if (IS_ERR(davinci_wdt->base)) + return PTR_ERR(davinci_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); - clk_disable_unprepare(wdt_clk); + struct davinci_wdt_device *davinci_wdt = platform_get_drvdata(pdev); + + watchdog_unregister_device(&davinci_wdt->wdd); + clk_disable_unprepare(davinci_wdt->clk); return 0; } |