*
* 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
#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: "
#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)
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;
}
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