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authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-08-07 04:55:03 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-08-07 04:55:03 -0400
commit4fb8af10d0fd09372d52966b76922b9e82bbc950 (patch)
treed240e4d40357583e3f3eb228dccf20122a5b31ed /drivers/watchdog/ar7_wdt.c
parentf44f82e8a20b98558486eb14497b2f71c78fa325 (diff)
parent64a99d2a8c3ed5c4e39f3ae1cc682aa8fd3977fc (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes
Diffstat (limited to 'drivers/watchdog/ar7_wdt.c')
-rw-r--r--drivers/watchdog/ar7_wdt.c29
1 files changed, 17 insertions, 12 deletions
diff --git a/drivers/watchdog/ar7_wdt.c b/drivers/watchdog/ar7_wdt.c
index 2eb48c0df32c..ef7b0d67095e 100644
--- a/drivers/watchdog/ar7_wdt.c
+++ b/drivers/watchdog/ar7_wdt.c
@@ -69,7 +69,8 @@ struct ar7_wdt {
69 u32 prescale; 69 u32 prescale;
70}; 70};
71 71
72static struct semaphore open_semaphore; 72static unsigned long wdt_is_open;
73static spinlock_t wdt_lock;
73static unsigned expect_close; 74static unsigned expect_close;
74 75
75/* XXX currently fixed, allows max margin ~68.72 secs */ 76/* XXX currently fixed, allows max margin ~68.72 secs */
@@ -154,8 +155,10 @@ static void ar7_wdt_update_margin(int new_margin)
154 u32 change; 155 u32 change;
155 156
156 change = new_margin * (ar7_vbus_freq() / prescale_value); 157 change = new_margin * (ar7_vbus_freq() / prescale_value);
157 if (change < 1) change = 1; 158 if (change < 1)
158 if (change > 0xffff) change = 0xffff; 159 change = 1;
160 if (change > 0xffff)
161 change = 0xffff;
159 ar7_wdt_change(change); 162 ar7_wdt_change(change);
160 margin = change * prescale_value / ar7_vbus_freq(); 163 margin = change * prescale_value / ar7_vbus_freq();
161 printk(KERN_INFO DRVNAME 164 printk(KERN_INFO DRVNAME
@@ -179,7 +182,7 @@ static void ar7_wdt_disable_wdt(void)
179static int ar7_wdt_open(struct inode *inode, struct file *file) 182static int ar7_wdt_open(struct inode *inode, struct file *file)
180{ 183{
181 /* only allow one at a time */ 184 /* only allow one at a time */
182 if (down_trylock(&open_semaphore)) 185 if (test_and_set_bit(0, &wdt_is_open))
183 return -EBUSY; 186 return -EBUSY;
184 ar7_wdt_enable_wdt(); 187 ar7_wdt_enable_wdt();
185 expect_close = 0; 188 expect_close = 0;
@@ -195,9 +198,7 @@ static int ar7_wdt_release(struct inode *inode, struct file *file)
195 "will not disable the watchdog timer\n"); 198 "will not disable the watchdog timer\n");
196 else if (!nowayout) 199 else if (!nowayout)
197 ar7_wdt_disable_wdt(); 200 ar7_wdt_disable_wdt();
198 201 clear_bit(0, &wdt_is_open);
199 up(&open_semaphore);
200
201 return 0; 202 return 0;
202} 203}
203 204
@@ -222,7 +223,9 @@ static ssize_t ar7_wdt_write(struct file *file, const char *data,
222 if (len) { 223 if (len) {
223 size_t i; 224 size_t i;
224 225
226 spin_lock(&wdt_lock);
225 ar7_wdt_kick(1); 227 ar7_wdt_kick(1);
228 spin_unlock(&wdt_lock);
226 229
227 expect_close = 0; 230 expect_close = 0;
228 for (i = 0; i < len; ++i) { 231 for (i = 0; i < len; ++i) {
@@ -237,8 +240,8 @@ static ssize_t ar7_wdt_write(struct file *file, const char *data,
237 return len; 240 return len;
238} 241}
239 242
240static int ar7_wdt_ioctl(struct inode *inode, struct file *file, 243static long ar7_wdt_ioctl(struct file *file,
241 unsigned int cmd, unsigned long arg) 244 unsigned int cmd, unsigned long arg)
242{ 245{
243 static struct watchdog_info ident = { 246 static struct watchdog_info ident = {
244 .identity = LONGNAME, 247 .identity = LONGNAME,
@@ -269,8 +272,10 @@ static int ar7_wdt_ioctl(struct inode *inode, struct file *file,
269 if (new_margin < 1) 272 if (new_margin < 1)
270 return -EINVAL; 273 return -EINVAL;
271 274
275 spin_lock(&wdt_lock);
272 ar7_wdt_update_margin(new_margin); 276 ar7_wdt_update_margin(new_margin);
273 ar7_wdt_kick(1); 277 ar7_wdt_kick(1);
278 spin_unlock(&wdt_lock);
274 279
275 case WDIOC_GETTIMEOUT: 280 case WDIOC_GETTIMEOUT:
276 if (put_user(margin, (int *)arg)) 281 if (put_user(margin, (int *)arg))
@@ -282,7 +287,7 @@ static int ar7_wdt_ioctl(struct inode *inode, struct file *file,
282static const struct file_operations ar7_wdt_fops = { 287static const struct file_operations ar7_wdt_fops = {
283 .owner = THIS_MODULE, 288 .owner = THIS_MODULE,
284 .write = ar7_wdt_write, 289 .write = ar7_wdt_write,
285 .ioctl = ar7_wdt_ioctl, 290 .unlocked_ioctl = ar7_wdt_ioctl,
286 .open = ar7_wdt_open, 291 .open = ar7_wdt_open,
287 .release = ar7_wdt_release, 292 .release = ar7_wdt_release,
288}; 293};
@@ -297,6 +302,8 @@ static int __init ar7_wdt_init(void)
297{ 302{
298 int rc; 303 int rc;
299 304
305 spin_lock_init(&wdt_lock);
306
300 ar7_wdt_get_regs(); 307 ar7_wdt_get_regs();
301 308
302 if (!request_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt), 309 if (!request_mem_region(ar7_regs_wdt, sizeof(struct ar7_wdt),
@@ -312,8 +319,6 @@ static int __init ar7_wdt_init(void)
312 ar7_wdt_prescale(prescale_value); 319 ar7_wdt_prescale(prescale_value);
313 ar7_wdt_update_margin(margin); 320 ar7_wdt_update_margin(margin);
314 321
315 sema_init(&open_semaphore, 1);
316
317 rc = register_reboot_notifier(&ar7_wdt_notifier); 322 rc = register_reboot_notifier(&ar7_wdt_notifier);
318 if (rc) { 323 if (rc) {
319 printk(KERN_ERR DRVNAME 324 printk(KERN_ERR DRVNAME