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path: root/drivers/watchdog/mv64x60_wdt.c
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Diffstat (limited to 'drivers/watchdog/mv64x60_wdt.c')
-rw-r--r--drivers/watchdog/mv64x60_wdt.c324
1 files changed, 0 insertions, 324 deletions
diff --git a/drivers/watchdog/mv64x60_wdt.c b/drivers/watchdog/mv64x60_wdt.c
deleted file mode 100644
index 894aa63488d3..000000000000
--- a/drivers/watchdog/mv64x60_wdt.c
+++ /dev/null
@@ -1,324 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * mv64x60_wdt.c - MV64X60 (Marvell Discovery) watchdog userspace interface
- *
- * Author: James Chapman <jchapman@katalix.com>
- *
- * Platform-specific setup code should configure the dog to generate
- * interrupt or reset as required. This code only enables/disables
- * and services the watchdog.
- *
- * Derived from mpc8xx_wdt.c, with the following copyright.
- *
- * 2002 (c) Florian Schirmer <jolt@tuxbox.org>
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/miscdevice.h>
-#include <linux/module.h>
-#include <linux/watchdog.h>
-#include <linux/platform_device.h>
-#include <linux/mv643xx.h>
-#include <linux/uaccess.h>
-#include <linux/io.h>
-
-#define MV64x60_WDT_WDC_OFFSET 0
-
-/*
- * The watchdog configuration register contains a pair of 2-bit fields,
- * 1. a reload field, bits 27-26, which triggers a reload of
- * the countdown register, and
- * 2. an enable field, bits 25-24, which toggles between
- * enabling and disabling the watchdog timer.
- * Bit 31 is a read-only field which indicates whether the
- * watchdog timer is currently enabled.
- *
- * The low 24 bits contain the timer reload value.
- */
-#define MV64x60_WDC_ENABLE_SHIFT 24
-#define MV64x60_WDC_SERVICE_SHIFT 26
-#define MV64x60_WDC_ENABLED_SHIFT 31
-
-#define MV64x60_WDC_ENABLED_TRUE 1
-#define MV64x60_WDC_ENABLED_FALSE 0
-
-/* Flags bits */
-#define MV64x60_WDOG_FLAG_OPENED 0
-
-static unsigned long wdt_flags;
-static int wdt_status;
-static void __iomem *mv64x60_wdt_regs;
-static int mv64x60_wdt_timeout;
-static int mv64x60_wdt_count;
-static unsigned int bus_clk;
-static char expect_close;
-static DEFINE_SPINLOCK(mv64x60_wdt_spinlock);
-
-static bool nowayout = WATCHDOG_NOWAYOUT;
-module_param(nowayout, bool, 0);
-MODULE_PARM_DESC(nowayout,
- "Watchdog cannot be stopped once started (default="
- __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-
-static int mv64x60_wdt_toggle_wdc(int enabled_predicate, int field_shift)
-{
- u32 data;
- u32 enabled;
- int ret = 0;
-
- spin_lock(&mv64x60_wdt_spinlock);
- data = readl(mv64x60_wdt_regs + MV64x60_WDT_WDC_OFFSET);
- enabled = (data >> MV64x60_WDC_ENABLED_SHIFT) & 1;
-
- /* only toggle the requested field if enabled state matches predicate */
- if ((enabled ^ enabled_predicate) == 0) {
- /* We write a 1, then a 2 -- to the appropriate field */
- data = (1 << field_shift) | mv64x60_wdt_count;
- writel(data, mv64x60_wdt_regs + MV64x60_WDT_WDC_OFFSET);
-
- data = (2 << field_shift) | mv64x60_wdt_count;
- writel(data, mv64x60_wdt_regs + MV64x60_WDT_WDC_OFFSET);
- ret = 1;
- }
- spin_unlock(&mv64x60_wdt_spinlock);
-
- return ret;
-}
-
-static void mv64x60_wdt_service(void)
-{
- mv64x60_wdt_toggle_wdc(MV64x60_WDC_ENABLED_TRUE,
- MV64x60_WDC_SERVICE_SHIFT);
-}
-
-static void mv64x60_wdt_handler_enable(void)
-{
- if (mv64x60_wdt_toggle_wdc(MV64x60_WDC_ENABLED_FALSE,
- MV64x60_WDC_ENABLE_SHIFT)) {
- mv64x60_wdt_service();
- pr_notice("watchdog activated\n");
- }
-}
-
-static void mv64x60_wdt_handler_disable(void)
-{
- if (mv64x60_wdt_toggle_wdc(MV64x60_WDC_ENABLED_TRUE,
- MV64x60_WDC_ENABLE_SHIFT))
- pr_notice("watchdog deactivated\n");
-}
-
-static void mv64x60_wdt_set_timeout(unsigned int timeout)
-{
- /* maximum bus cycle count is 0xFFFFFFFF */
- if (timeout > 0xFFFFFFFF / bus_clk)
- timeout = 0xFFFFFFFF / bus_clk;
-
- mv64x60_wdt_count = timeout * bus_clk >> 8;
- mv64x60_wdt_timeout = timeout;
-}
-
-static int mv64x60_wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(MV64x60_WDOG_FLAG_OPENED, &wdt_flags))
- return -EBUSY;
-
- if (nowayout)
- __module_get(THIS_MODULE);
-
- mv64x60_wdt_handler_enable();
-
- return stream_open(inode, file);
-}
-
-static int mv64x60_wdt_release(struct inode *inode, struct file *file)
-{
- if (expect_close == 42)
- mv64x60_wdt_handler_disable();
- else {
- pr_crit("unexpected close, not stopping timer!\n");
- mv64x60_wdt_service();
- }
- expect_close = 0;
-
- clear_bit(MV64x60_WDOG_FLAG_OPENED, &wdt_flags);
-
- return 0;
-}
-
-static ssize_t mv64x60_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- if (len) {
- if (!nowayout) {
- size_t i;
-
- expect_close = 0;
-
- for (i = 0; i != len; i++) {
- char c;
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- expect_close = 42;
- }
- }
- mv64x60_wdt_service();
- }
-
- return len;
-}
-
-static long mv64x60_wdt_ioctl(struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- int timeout;
- int options;
- void __user *argp = (void __user *)arg;
- static const struct watchdog_info info = {
- .options = WDIOF_SETTIMEOUT |
- WDIOF_MAGICCLOSE |
- WDIOF_KEEPALIVEPING,
- .firmware_version = 0,
- .identity = "MV64x60 watchdog",
- };
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- if (copy_to_user(argp, &info, sizeof(info)))
- return -EFAULT;
- break;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- if (put_user(wdt_status, (int __user *)argp))
- return -EFAULT;
- wdt_status &= ~WDIOF_KEEPALIVEPING;
- break;
-
- case WDIOC_GETTEMP:
- return -EOPNOTSUPP;
-
- case WDIOC_SETOPTIONS:
- if (get_user(options, (int __user *)argp))
- return -EFAULT;
-
- if (options & WDIOS_DISABLECARD)
- mv64x60_wdt_handler_disable();
-
- if (options & WDIOS_ENABLECARD)
- mv64x60_wdt_handler_enable();
- break;
-
- case WDIOC_KEEPALIVE:
- mv64x60_wdt_service();
- wdt_status |= WDIOF_KEEPALIVEPING;
- break;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(timeout, (int __user *)argp))
- return -EFAULT;
- mv64x60_wdt_set_timeout(timeout);
- fallthrough;
-
- case WDIOC_GETTIMEOUT:
- if (put_user(mv64x60_wdt_timeout, (int __user *)argp))
- return -EFAULT;
- break;
-
- default:
- return -ENOTTY;
- }
-
- return 0;
-}
-
-static const struct file_operations mv64x60_wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = mv64x60_wdt_write,
- .unlocked_ioctl = mv64x60_wdt_ioctl,
- .compat_ioctl = compat_ptr_ioctl,
- .open = mv64x60_wdt_open,
- .release = mv64x60_wdt_release,
-};
-
-static struct miscdevice mv64x60_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &mv64x60_wdt_fops,
-};
-
-static int mv64x60_wdt_probe(struct platform_device *dev)
-{
- struct mv64x60_wdt_pdata *pdata = dev_get_platdata(&dev->dev);
- struct resource *r;
- int timeout = 10;
-
- bus_clk = 133; /* in MHz */
- if (pdata) {
- timeout = pdata->timeout;
- bus_clk = pdata->bus_clk;
- }
-
- /* Since bus_clk is truncated MHz, actual frequency could be
- * up to 1MHz higher. Round up, since it's better to time out
- * too late than too soon.
- */
- bus_clk++;
- bus_clk *= 1000000; /* convert to Hz */
-
- r = platform_get_resource(dev, IORESOURCE_MEM, 0);
- if (!r)
- return -ENODEV;
-
- mv64x60_wdt_regs = devm_ioremap(&dev->dev, r->start, resource_size(r));
- if (mv64x60_wdt_regs == NULL)
- return -ENOMEM;
-
- mv64x60_wdt_set_timeout(timeout);
-
- mv64x60_wdt_handler_disable(); /* in case timer was already running */
-
- return misc_register(&mv64x60_wdt_miscdev);
-}
-
-static int mv64x60_wdt_remove(struct platform_device *dev)
-{
- misc_deregister(&mv64x60_wdt_miscdev);
-
- mv64x60_wdt_handler_disable();
-
- return 0;
-}
-
-static struct platform_driver mv64x60_wdt_driver = {
- .probe = mv64x60_wdt_probe,
- .remove = mv64x60_wdt_remove,
- .driver = {
- .name = MV64x60_WDT_NAME,
- },
-};
-
-static int __init mv64x60_wdt_init(void)
-{
- pr_info("MV64x60 watchdog driver\n");
-
- return platform_driver_register(&mv64x60_wdt_driver);
-}
-
-static void __exit mv64x60_wdt_exit(void)
-{
- platform_driver_unregister(&mv64x60_wdt_driver);
-}
-
-module_init(mv64x60_wdt_init);
-module_exit(mv64x60_wdt_exit);
-
-MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
-MODULE_DESCRIPTION("MV64x60 watchdog driver");
-MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:" MV64x60_WDT_NAME);