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authormatthieu castet <castet.matthieu@free.fr>2009-06-05 12:57:18 -0400
committerWim Van Sebroeck <wim@iguana.be>2009-06-20 14:40:56 -0400
commit90074dce5537e87b27125505bb89a373567a7ede (patch)
tree631cd42c3bc92e9182cc74893edefcb266c8e51a /drivers/watchdog
parentaccde1684ff1ea607557fb7224d2dd57775117e1 (diff)
[WATCHDOG] add bcm47xx watchdog driver
This add watchdog driver for broadcom 47xx device. It uses the ssb subsytem to access embeded watchdog device. Because the watchdog timeout is very short (about 2s), a soft timer is used to increase the watchdog period. Note : A patch for exporting the ssb_watchdog_timer_set will be submitted on next linux-mips merge. Without this patch it can't be build as a module. Signed-off-by: Aleksandar Radovanovic <biblbroks@sezampro.rs> Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr> Tested-by: Florian Fainelli <florian@openwrt.org> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/Kconfig6
-rw-r--r--drivers/watchdog/Makefile1
-rw-r--r--drivers/watchdog/bcm47xx_wdt.c286
3 files changed, 293 insertions, 0 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 70d7f8cc06b7..e8d45b6ccef8 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -729,6 +729,12 @@ config SBC_EPX_C3_WATCHDOG
729 729
730# MIPS Architecture 730# MIPS Architecture
731 731
732config BCM47XX_WDT
733 tristate "Broadcom BCM47xx Watchdog Timer"
734 depends on BCM47XX
735 help
736 Hardware driver for the Broadcom BCM47xx Watchog Timer.
737
732config RC32434_WDT 738config RC32434_WDT
733 tristate "IDT RC32434 SoC Watchdog Timer" 739 tristate "IDT RC32434 SoC Watchdog Timer"
734 depends on MIKROTIK_RB532 740 depends on MIKROTIK_RB532
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index d437d5c2d22e..3d774294a2b7 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -101,6 +101,7 @@ obj-$(CONFIG_SBC_EPX_C3_WATCHDOG) += sbc_epx_c3.o
101# M68KNOMMU Architecture 101# M68KNOMMU Architecture
102 102
103# MIPS Architecture 103# MIPS Architecture
104obj-$(CONFIG_BCM47XX_WDT) += bcm47xx_wdt.o
104obj-$(CONFIG_RC32434_WDT) += rc32434_wdt.o 105obj-$(CONFIG_RC32434_WDT) += rc32434_wdt.o
105obj-$(CONFIG_INDYDOG) += indydog.o 106obj-$(CONFIG_INDYDOG) += indydog.o
106obj-$(CONFIG_WDT_MTX1) += mtx-1_wdt.o 107obj-$(CONFIG_WDT_MTX1) += mtx-1_wdt.o
diff --git a/drivers/watchdog/bcm47xx_wdt.c b/drivers/watchdog/bcm47xx_wdt.c
new file mode 100644
index 000000000000..5c7011cda6a6
--- /dev/null
+++ b/drivers/watchdog/bcm47xx_wdt.c
@@ -0,0 +1,286 @@
1/*
2 * Watchdog driver for Broadcom BCM47XX
3 *
4 * Copyright (C) 2008 Aleksandar Radovanovic <biblbroks@sezampro.rs>
5 * Copyright (C) 2009 Matthieu CASTET <castet.matthieu@free.fr>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#include <linux/bitops.h>
14#include <linux/errno.h>
15#include <linux/fs.h>
16#include <linux/init.h>
17#include <linux/kernel.h>
18#include <linux/miscdevice.h>
19#include <linux/module.h>
20#include <linux/moduleparam.h>
21#include <linux/reboot.h>
22#include <linux/types.h>
23#include <linux/uaccess.h>
24#include <linux/watchdog.h>
25#include <linux/timer.h>
26#include <linux/jiffies.h>
27#include <linux/ssb/ssb_embedded.h>
28#include <asm/mach-bcm47xx/bcm47xx.h>
29
30#define DRV_NAME "bcm47xx_wdt"
31
32#define WDT_DEFAULT_TIME 30 /* seconds */
33#define WDT_MAX_TIME 255 /* seconds */
34
35static int wdt_time = WDT_DEFAULT_TIME;
36static int nowayout = WATCHDOG_NOWAYOUT;
37
38module_param(wdt_time, int, 0);
39MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="
40 __MODULE_STRING(WDT_DEFAULT_TIME) ")");
41
42#ifdef CONFIG_WATCHDOG_NOWAYOUT
43module_param(nowayout, int, 0);
44MODULE_PARM_DESC(nowayout,
45 "Watchdog cannot be stopped once started (default="
46 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
47#endif
48
49static unsigned long bcm47xx_wdt_busy;
50static char expect_release;
51static struct timer_list wdt_timer;
52static atomic_t ticks;
53
54static inline void bcm47xx_wdt_hw_start(void)
55{
56 /* this is 2,5s on 100Mhz clock and 2s on 133 Mhz */
57 ssb_watchdog_timer_set(&ssb_bcm47xx, 0xfffffff);
58}
59
60static inline int bcm47xx_wdt_hw_stop(void)
61{
62 return ssb_watchdog_timer_set(&ssb_bcm47xx, 0);
63}
64
65static void bcm47xx_timer_tick(unsigned long unused)
66{
67 if (!atomic_dec_and_test(&ticks)) {
68 bcm47xx_wdt_hw_start();
69 mod_timer(&wdt_timer, jiffies + HZ);
70 } else {
71 printk(KERN_CRIT DRV_NAME "Watchdog will fire soon!!!\n");
72 }
73}
74
75static inline void bcm47xx_wdt_pet(void)
76{
77 atomic_set(&ticks, wdt_time);
78}
79
80static void bcm47xx_wdt_start(void)
81{
82 bcm47xx_wdt_pet();
83 bcm47xx_timer_tick(0);
84}
85
86static void bcm47xx_wdt_pause(void)
87{
88 del_timer_sync(&wdt_timer);
89 bcm47xx_wdt_hw_stop();
90}
91
92static void bcm47xx_wdt_stop(void)
93{
94 bcm47xx_wdt_pause();
95}
96
97static int bcm47xx_wdt_settimeout(int new_time)
98{
99 if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
100 return -EINVAL;
101
102 wdt_time = new_time;
103 return 0;
104}
105
106static int bcm47xx_wdt_open(struct inode *inode, struct file *file)
107{
108 if (test_and_set_bit(0, &bcm47xx_wdt_busy))
109 return -EBUSY;
110
111 bcm47xx_wdt_start();
112 return nonseekable_open(inode, file);
113}
114
115static int bcm47xx_wdt_release(struct inode *inode, struct file *file)
116{
117 if (expect_release == 42) {
118 bcm47xx_wdt_stop();
119 } else {
120 printk(KERN_CRIT DRV_NAME
121 ": Unexpected close, not stopping watchdog!\n");
122 bcm47xx_wdt_start();
123 }
124
125 clear_bit(0, &bcm47xx_wdt_busy);
126 expect_release = 0;
127 return 0;
128}
129
130static ssize_t bcm47xx_wdt_write(struct file *file, const char __user *data,
131 size_t len, loff_t *ppos)
132{
133 if (len) {
134 if (!nowayout) {
135 size_t i;
136
137 expect_release = 0;
138
139 for (i = 0; i != len; i++) {
140 char c;
141 if (get_user(c, data + i))
142 return -EFAULT;
143 if (c == 'V')
144 expect_release = 42;
145 }
146 }
147 bcm47xx_wdt_pet();
148 }
149 return len;
150}
151
152static struct watchdog_info bcm47xx_wdt_info = {
153 .identity = DRV_NAME,
154 .options = WDIOF_SETTIMEOUT |
155 WDIOF_KEEPALIVEPING |
156 WDIOF_MAGICCLOSE,
157};
158
159static long bcm47xx_wdt_ioctl(struct file *file,
160 unsigned int cmd, unsigned long arg)
161{
162 void __user *argp = (void __user *)arg;
163 int __user *p = argp;
164 int new_value, retval = -EINVAL;;
165
166 switch (cmd) {
167 case WDIOC_GETSUPPORT:
168 return copy_to_user(argp, &bcm47xx_wdt_info,
169 sizeof(bcm47xx_wdt_info)) ? -EFAULT : 0;
170
171 case WDIOC_GETSTATUS:
172 case WDIOC_GETBOOTSTATUS:
173 return put_user(0, p);
174
175 case WDIOC_SETOPTIONS:
176 if (get_user(new_value, p))
177 return -EFAULT;
178
179 if (new_value & WDIOS_DISABLECARD) {
180 bcm47xx_wdt_stop();
181 retval = 0;
182 }
183
184 if (new_value & WDIOS_ENABLECARD) {
185 bcm47xx_wdt_start();
186 retval = 0;
187 }
188
189 return retval;
190
191 case WDIOC_KEEPALIVE:
192 bcm47xx_wdt_pet();
193 return 0;
194
195 case WDIOC_SETTIMEOUT:
196 if (get_user(new_value, p))
197 return -EFAULT;
198
199 if (bcm47xx_wdt_settimeout(new_value))
200 return -EINVAL;
201
202 bcm47xx_wdt_pet();
203
204 case WDIOC_GETTIMEOUT:
205 return put_user(wdt_time, p);
206
207 default:
208 return -ENOTTY;
209 }
210}
211
212static int bcm47xx_wdt_notify_sys(struct notifier_block *this,
213 unsigned long code, void *unused)
214{
215 if (code == SYS_DOWN || code == SYS_HALT)
216 bcm47xx_wdt_stop();
217 return NOTIFY_DONE;
218}
219
220static const struct file_operations bcm47xx_wdt_fops = {
221 .owner = THIS_MODULE,
222 .llseek = no_llseek,
223 .unlocked_ioctl = bcm47xx_wdt_ioctl,
224 .open = bcm47xx_wdt_open,
225 .release = bcm47xx_wdt_release,
226 .write = bcm47xx_wdt_write,
227};
228
229static struct miscdevice bcm47xx_wdt_miscdev = {
230 .minor = WATCHDOG_MINOR,
231 .name = "watchdog",
232 .fops = &bcm47xx_wdt_fops,
233};
234
235static struct notifier_block bcm47xx_wdt_notifier = {
236 .notifier_call = bcm47xx_wdt_notify_sys,
237};
238
239static int __init bcm47xx_wdt_init(void)
240{
241 int ret;
242
243 if (bcm47xx_wdt_hw_stop() < 0)
244 return -ENODEV;
245
246 setup_timer(&wdt_timer, bcm47xx_timer_tick, 0L);
247
248 if (bcm47xx_wdt_settimeout(wdt_time)) {
249 bcm47xx_wdt_settimeout(WDT_DEFAULT_TIME);
250 printk(KERN_INFO DRV_NAME ": "
251 "wdt_time value must be 0 < wdt_time < %d, using %d\n",
252 (WDT_MAX_TIME + 1), wdt_time);
253 }
254
255 ret = register_reboot_notifier(&bcm47xx_wdt_notifier);
256 if (ret)
257 return ret;
258
259 ret = misc_register(&bcm47xx_wdt_miscdev);
260 if (ret) {
261 unregister_reboot_notifier(&bcm47xx_wdt_notifier);
262 return ret;
263 }
264
265 printk(KERN_INFO "BCM47xx Watchdog Timer enabled (%d seconds%s)\n",
266 wdt_time, nowayout ? ", nowayout" : "");
267 return 0;
268}
269
270static void __exit bcm47xx_wdt_exit(void)
271{
272 if (!nowayout)
273 bcm47xx_wdt_stop();
274
275 misc_deregister(&bcm47xx_wdt_miscdev);
276
277 unregister_reboot_notifier(&bcm47xx_wdt_notifier);
278}
279
280module_init(bcm47xx_wdt_init);
281module_exit(bcm47xx_wdt_exit);
282
283MODULE_AUTHOR("Aleksandar Radovanovic");
284MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
285MODULE_LICENSE("GPL");
286MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);