diff options
Diffstat (limited to 'drivers/watchdog/sp805_wdt.c')
-rw-r--r-- | drivers/watchdog/sp805_wdt.c | 249 |
1 files changed, 90 insertions, 159 deletions
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c index bbb170e50055..afcd13676542 100644 --- a/drivers/watchdog/sp805_wdt.c +++ b/drivers/watchdog/sp805_wdt.c | |||
@@ -16,20 +16,17 @@ | |||
16 | #include <linux/amba/bus.h> | 16 | #include <linux/amba/bus.h> |
17 | #include <linux/bitops.h> | 17 | #include <linux/bitops.h> |
18 | #include <linux/clk.h> | 18 | #include <linux/clk.h> |
19 | #include <linux/fs.h> | ||
20 | #include <linux/init.h> | 19 | #include <linux/init.h> |
21 | #include <linux/io.h> | 20 | #include <linux/io.h> |
22 | #include <linux/ioport.h> | 21 | #include <linux/ioport.h> |
23 | #include <linux/kernel.h> | 22 | #include <linux/kernel.h> |
24 | #include <linux/math64.h> | 23 | #include <linux/math64.h> |
25 | #include <linux/miscdevice.h> | ||
26 | #include <linux/module.h> | 24 | #include <linux/module.h> |
27 | #include <linux/moduleparam.h> | 25 | #include <linux/moduleparam.h> |
28 | #include <linux/pm.h> | 26 | #include <linux/pm.h> |
29 | #include <linux/slab.h> | 27 | #include <linux/slab.h> |
30 | #include <linux/spinlock.h> | 28 | #include <linux/spinlock.h> |
31 | #include <linux/types.h> | 29 | #include <linux/types.h> |
32 | #include <linux/uaccess.h> | ||
33 | #include <linux/watchdog.h> | 30 | #include <linux/watchdog.h> |
34 | 31 | ||
35 | /* default timeout in seconds */ | 32 | /* default timeout in seconds */ |
@@ -56,6 +53,7 @@ | |||
56 | 53 | ||
57 | /** | 54 | /** |
58 | * struct sp805_wdt: sp805 wdt device structure | 55 | * struct sp805_wdt: sp805 wdt device structure |
56 | * @wdd: instance of struct watchdog_device | ||
59 | * @lock: spin lock protecting dev structure and io access | 57 | * @lock: spin lock protecting dev structure and io access |
60 | * @base: base address of wdt | 58 | * @base: base address of wdt |
61 | * @clk: clock structure of wdt | 59 | * @clk: clock structure of wdt |
@@ -65,24 +63,24 @@ | |||
65 | * @timeout: current programmed timeout | 63 | * @timeout: current programmed timeout |
66 | */ | 64 | */ |
67 | struct sp805_wdt { | 65 | struct sp805_wdt { |
66 | struct watchdog_device wdd; | ||
68 | spinlock_t lock; | 67 | spinlock_t lock; |
69 | void __iomem *base; | 68 | void __iomem *base; |
70 | struct clk *clk; | 69 | struct clk *clk; |
71 | struct amba_device *adev; | 70 | struct amba_device *adev; |
72 | unsigned long status; | ||
73 | #define WDT_BUSY 0 | ||
74 | #define WDT_CAN_BE_CLOSED 1 | ||
75 | unsigned int load_val; | 71 | unsigned int load_val; |
76 | unsigned int timeout; | 72 | unsigned int timeout; |
77 | }; | 73 | }; |
78 | 74 | ||
79 | /* local variables */ | ||
80 | static struct sp805_wdt *wdt; | ||
81 | static bool nowayout = WATCHDOG_NOWAYOUT; | 75 | static bool nowayout = WATCHDOG_NOWAYOUT; |
76 | module_param(nowayout, bool, 0); | ||
77 | MODULE_PARM_DESC(nowayout, | ||
78 | "Set to 1 to keep watchdog running after device release"); | ||
82 | 79 | ||
83 | /* This routine finds load value that will reset system in required timout */ | 80 | /* This routine finds load value that will reset system in required timout */ |
84 | static void wdt_setload(unsigned int timeout) | 81 | static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout) |
85 | { | 82 | { |
83 | struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); | ||
86 | u64 load, rate; | 84 | u64 load, rate; |
87 | 85 | ||
88 | rate = clk_get_rate(wdt->clk); | 86 | rate = clk_get_rate(wdt->clk); |
@@ -103,11 +101,14 @@ static void wdt_setload(unsigned int timeout) | |||
103 | /* roundup timeout to closest positive integer value */ | 101 | /* roundup timeout to closest positive integer value */ |
104 | wdt->timeout = div_u64((load + 1) * 2 + (rate / 2), rate); | 102 | wdt->timeout = div_u64((load + 1) * 2 + (rate / 2), rate); |
105 | spin_unlock(&wdt->lock); | 103 | spin_unlock(&wdt->lock); |
104 | |||
105 | return 0; | ||
106 | } | 106 | } |
107 | 107 | ||
108 | /* returns number of seconds left for reset to occur */ | 108 | /* returns number of seconds left for reset to occur */ |
109 | static u32 wdt_timeleft(void) | 109 | static unsigned int wdt_timeleft(struct watchdog_device *wdd) |
110 | { | 110 | { |
111 | struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); | ||
111 | u64 load, rate; | 112 | u64 load, rate; |
112 | 113 | ||
113 | rate = clk_get_rate(wdt->clk); | 114 | rate = clk_get_rate(wdt->clk); |
@@ -123,166 +124,96 @@ static u32 wdt_timeleft(void) | |||
123 | return div_u64(load, rate); | 124 | return div_u64(load, rate); |
124 | } | 125 | } |
125 | 126 | ||
126 | /* enables watchdog timers reset */ | 127 | static int wdt_config(struct watchdog_device *wdd, bool ping) |
127 | static void wdt_enable(void) | ||
128 | { | 128 | { |
129 | spin_lock(&wdt->lock); | 129 | struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); |
130 | int ret; | ||
130 | 131 | ||
131 | writel_relaxed(UNLOCK, wdt->base + WDTLOCK); | 132 | if (!ping) { |
132 | writel_relaxed(wdt->load_val, wdt->base + WDTLOAD); | 133 | ret = clk_prepare(wdt->clk); |
133 | writel_relaxed(INT_MASK, wdt->base + WDTINTCLR); | 134 | if (ret) { |
134 | writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL); | 135 | dev_err(&wdt->adev->dev, "clock prepare fail"); |
135 | writel_relaxed(LOCK, wdt->base + WDTLOCK); | 136 | return ret; |
137 | } | ||
136 | 138 | ||
137 | /* Flush posted writes. */ | 139 | ret = clk_enable(wdt->clk); |
138 | readl_relaxed(wdt->base + WDTLOCK); | 140 | if (ret) { |
139 | spin_unlock(&wdt->lock); | 141 | dev_err(&wdt->adev->dev, "clock enable fail"); |
140 | } | 142 | clk_unprepare(wdt->clk); |
143 | return ret; | ||
144 | } | ||
145 | } | ||
141 | 146 | ||
142 | /* disables watchdog timers reset */ | ||
143 | static void wdt_disable(void) | ||
144 | { | ||
145 | spin_lock(&wdt->lock); | 147 | spin_lock(&wdt->lock); |
146 | 148 | ||
147 | writel_relaxed(UNLOCK, wdt->base + WDTLOCK); | 149 | writel_relaxed(UNLOCK, wdt->base + WDTLOCK); |
148 | writel_relaxed(0, wdt->base + WDTCONTROL); | 150 | writel_relaxed(wdt->load_val, wdt->base + WDTLOAD); |
151 | |||
152 | if (!ping) { | ||
153 | writel_relaxed(INT_MASK, wdt->base + WDTINTCLR); | ||
154 | writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + | ||
155 | WDTCONTROL); | ||
156 | } | ||
157 | |||
149 | writel_relaxed(LOCK, wdt->base + WDTLOCK); | 158 | writel_relaxed(LOCK, wdt->base + WDTLOCK); |
150 | 159 | ||
151 | /* Flush posted writes. */ | 160 | /* Flush posted writes. */ |
152 | readl_relaxed(wdt->base + WDTLOCK); | 161 | readl_relaxed(wdt->base + WDTLOCK); |
153 | spin_unlock(&wdt->lock); | 162 | spin_unlock(&wdt->lock); |
163 | |||
164 | return 0; | ||
154 | } | 165 | } |
155 | 166 | ||
156 | static ssize_t sp805_wdt_write(struct file *file, const char *data, | 167 | static int wdt_ping(struct watchdog_device *wdd) |
157 | size_t len, loff_t *ppos) | ||
158 | { | 168 | { |
159 | if (len) { | 169 | return wdt_config(wdd, true); |
160 | if (!nowayout) { | ||
161 | size_t i; | ||
162 | |||
163 | clear_bit(WDT_CAN_BE_CLOSED, &wdt->status); | ||
164 | |||
165 | for (i = 0; i != len; i++) { | ||
166 | char c; | ||
167 | |||
168 | if (get_user(c, data + i)) | ||
169 | return -EFAULT; | ||
170 | /* Check for Magic Close character */ | ||
171 | if (c == 'V') { | ||
172 | set_bit(WDT_CAN_BE_CLOSED, | ||
173 | &wdt->status); | ||
174 | break; | ||
175 | } | ||
176 | } | ||
177 | } | ||
178 | wdt_enable(); | ||
179 | } | ||
180 | return len; | ||
181 | } | 170 | } |
182 | 171 | ||
183 | static const struct watchdog_info ident = { | 172 | /* enables watchdog timers reset */ |
184 | .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | 173 | static int wdt_enable(struct watchdog_device *wdd) |
185 | .identity = MODULE_NAME, | ||
186 | }; | ||
187 | |||
188 | static long sp805_wdt_ioctl(struct file *file, unsigned int cmd, | ||
189 | unsigned long arg) | ||
190 | { | 174 | { |
191 | int ret = -ENOTTY; | 175 | return wdt_config(wdd, false); |
192 | unsigned int timeout; | ||
193 | |||
194 | switch (cmd) { | ||
195 | case WDIOC_GETSUPPORT: | ||
196 | ret = copy_to_user((struct watchdog_info *)arg, &ident, | ||
197 | sizeof(ident)) ? -EFAULT : 0; | ||
198 | break; | ||
199 | |||
200 | case WDIOC_GETSTATUS: | ||
201 | ret = put_user(0, (int *)arg); | ||
202 | break; | ||
203 | |||
204 | case WDIOC_KEEPALIVE: | ||
205 | wdt_enable(); | ||
206 | ret = 0; | ||
207 | break; | ||
208 | |||
209 | case WDIOC_SETTIMEOUT: | ||
210 | ret = get_user(timeout, (unsigned int *)arg); | ||
211 | if (ret) | ||
212 | break; | ||
213 | |||
214 | wdt_setload(timeout); | ||
215 | |||
216 | wdt_enable(); | ||
217 | /* Fall through */ | ||
218 | |||
219 | case WDIOC_GETTIMEOUT: | ||
220 | ret = put_user(wdt->timeout, (unsigned int *)arg); | ||
221 | break; | ||
222 | case WDIOC_GETTIMELEFT: | ||
223 | ret = put_user(wdt_timeleft(), (unsigned int *)arg); | ||
224 | break; | ||
225 | } | ||
226 | return ret; | ||
227 | } | 176 | } |
228 | 177 | ||
229 | static int sp805_wdt_open(struct inode *inode, struct file *file) | 178 | /* disables watchdog timers reset */ |
179 | static int wdt_disable(struct watchdog_device *wdd) | ||
230 | { | 180 | { |
231 | int ret = 0; | 181 | struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); |
232 | |||
233 | if (test_and_set_bit(WDT_BUSY, &wdt->status)) | ||
234 | return -EBUSY; | ||
235 | |||
236 | ret = clk_enable(wdt->clk); | ||
237 | if (ret) { | ||
238 | dev_err(&wdt->adev->dev, "clock enable fail"); | ||
239 | goto err; | ||
240 | } | ||
241 | |||
242 | wdt_enable(); | ||
243 | 182 | ||
244 | /* can not be closed, once enabled */ | 183 | spin_lock(&wdt->lock); |
245 | clear_bit(WDT_CAN_BE_CLOSED, &wdt->status); | ||
246 | return nonseekable_open(inode, file); | ||
247 | 184 | ||
248 | err: | 185 | writel_relaxed(UNLOCK, wdt->base + WDTLOCK); |
249 | clear_bit(WDT_BUSY, &wdt->status); | 186 | writel_relaxed(0, wdt->base + WDTCONTROL); |
250 | return ret; | 187 | writel_relaxed(LOCK, wdt->base + WDTLOCK); |
251 | } | ||
252 | 188 | ||
253 | static int sp805_wdt_release(struct inode *inode, struct file *file) | 189 | /* Flush posted writes. */ |
254 | { | 190 | readl_relaxed(wdt->base + WDTLOCK); |
255 | if (!test_bit(WDT_CAN_BE_CLOSED, &wdt->status)) { | 191 | spin_unlock(&wdt->lock); |
256 | clear_bit(WDT_BUSY, &wdt->status); | ||
257 | dev_warn(&wdt->adev->dev, "Device closed unexpectedly\n"); | ||
258 | return 0; | ||
259 | } | ||
260 | 192 | ||
261 | wdt_disable(); | ||
262 | clk_disable(wdt->clk); | 193 | clk_disable(wdt->clk); |
263 | clear_bit(WDT_BUSY, &wdt->status); | 194 | clk_unprepare(wdt->clk); |
264 | 195 | ||
265 | return 0; | 196 | return 0; |
266 | } | 197 | } |
267 | 198 | ||
268 | static const struct file_operations sp805_wdt_fops = { | 199 | static const struct watchdog_info wdt_info = { |
269 | .owner = THIS_MODULE, | 200 | .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, |
270 | .llseek = no_llseek, | 201 | .identity = MODULE_NAME, |
271 | .write = sp805_wdt_write, | ||
272 | .unlocked_ioctl = sp805_wdt_ioctl, | ||
273 | .open = sp805_wdt_open, | ||
274 | .release = sp805_wdt_release, | ||
275 | }; | 202 | }; |
276 | 203 | ||
277 | static struct miscdevice sp805_wdt_miscdev = { | 204 | static const struct watchdog_ops wdt_ops = { |
278 | .minor = WATCHDOG_MINOR, | 205 | .owner = THIS_MODULE, |
279 | .name = "watchdog", | 206 | .start = wdt_enable, |
280 | .fops = &sp805_wdt_fops, | 207 | .stop = wdt_disable, |
208 | .ping = wdt_ping, | ||
209 | .set_timeout = wdt_setload, | ||
210 | .get_timeleft = wdt_timeleft, | ||
281 | }; | 211 | }; |
282 | 212 | ||
283 | static int __devinit | 213 | static int __devinit |
284 | sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) | 214 | sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) |
285 | { | 215 | { |
216 | struct sp805_wdt *wdt; | ||
286 | int ret = 0; | 217 | int ret = 0; |
287 | 218 | ||
288 | if (!devm_request_mem_region(&adev->dev, adev->res.start, | 219 | if (!devm_request_mem_region(&adev->dev, adev->res.start, |
@@ -315,19 +246,26 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) | |||
315 | } | 246 | } |
316 | 247 | ||
317 | wdt->adev = adev; | 248 | wdt->adev = adev; |
249 | wdt->wdd.info = &wdt_info; | ||
250 | wdt->wdd.ops = &wdt_ops; | ||
251 | |||
318 | spin_lock_init(&wdt->lock); | 252 | spin_lock_init(&wdt->lock); |
319 | wdt_setload(DEFAULT_TIMEOUT); | 253 | watchdog_set_nowayout(&wdt->wdd, nowayout); |
254 | watchdog_set_drvdata(&wdt->wdd, wdt); | ||
255 | wdt_setload(&wdt->wdd, DEFAULT_TIMEOUT); | ||
320 | 256 | ||
321 | ret = misc_register(&sp805_wdt_miscdev); | 257 | ret = watchdog_register_device(&wdt->wdd); |
322 | if (ret < 0) { | 258 | if (ret) { |
323 | dev_warn(&adev->dev, "cannot register misc device\n"); | 259 | dev_err(&adev->dev, "watchdog_register_device() failed: %d\n", |
324 | goto err_misc_register; | 260 | ret); |
261 | goto err_register; | ||
325 | } | 262 | } |
263 | amba_set_drvdata(adev, wdt); | ||
326 | 264 | ||
327 | dev_info(&adev->dev, "registration successful\n"); | 265 | dev_info(&adev->dev, "registration successful\n"); |
328 | return 0; | 266 | return 0; |
329 | 267 | ||
330 | err_misc_register: | 268 | err_register: |
331 | clk_put(wdt->clk); | 269 | clk_put(wdt->clk); |
332 | err: | 270 | err: |
333 | dev_err(&adev->dev, "Probe Failed!!!\n"); | 271 | dev_err(&adev->dev, "Probe Failed!!!\n"); |
@@ -336,7 +274,11 @@ err: | |||
336 | 274 | ||
337 | static int __devexit sp805_wdt_remove(struct amba_device *adev) | 275 | static int __devexit sp805_wdt_remove(struct amba_device *adev) |
338 | { | 276 | { |
339 | misc_deregister(&sp805_wdt_miscdev); | 277 | struct sp805_wdt *wdt = amba_get_drvdata(adev); |
278 | |||
279 | watchdog_unregister_device(&wdt->wdd); | ||
280 | amba_set_drvdata(adev, NULL); | ||
281 | watchdog_set_drvdata(&wdt->wdd, NULL); | ||
340 | clk_put(wdt->clk); | 282 | clk_put(wdt->clk); |
341 | 283 | ||
342 | return 0; | 284 | return 0; |
@@ -345,28 +287,22 @@ static int __devexit sp805_wdt_remove(struct amba_device *adev) | |||
345 | #ifdef CONFIG_PM | 287 | #ifdef CONFIG_PM |
346 | static int sp805_wdt_suspend(struct device *dev) | 288 | static int sp805_wdt_suspend(struct device *dev) |
347 | { | 289 | { |
348 | if (test_bit(WDT_BUSY, &wdt->status)) { | 290 | struct sp805_wdt *wdt = dev_get_drvdata(dev); |
349 | wdt_disable(); | 291 | |
350 | clk_disable(wdt->clk); | 292 | if (watchdog_active(&wdt->wdd)) |
351 | } | 293 | return wdt_disable(&wdt->wdd); |
352 | 294 | ||
353 | return 0; | 295 | return 0; |
354 | } | 296 | } |
355 | 297 | ||
356 | static int sp805_wdt_resume(struct device *dev) | 298 | static int sp805_wdt_resume(struct device *dev) |
357 | { | 299 | { |
358 | int ret = 0; | 300 | struct sp805_wdt *wdt = dev_get_drvdata(dev); |
359 | 301 | ||
360 | if (test_bit(WDT_BUSY, &wdt->status)) { | 302 | if (watchdog_active(&wdt->wdd)) |
361 | ret = clk_enable(wdt->clk); | 303 | return wdt_enable(&wdt->wdd); |
362 | if (ret) { | ||
363 | dev_err(dev, "clock enable fail"); | ||
364 | return ret; | ||
365 | } | ||
366 | wdt_enable(); | ||
367 | } | ||
368 | 304 | ||
369 | return ret; | 305 | return 0; |
370 | } | 306 | } |
371 | #endif /* CONFIG_PM */ | 307 | #endif /* CONFIG_PM */ |
372 | 308 | ||
@@ -395,11 +331,6 @@ static struct amba_driver sp805_wdt_driver = { | |||
395 | 331 | ||
396 | module_amba_driver(sp805_wdt_driver); | 332 | module_amba_driver(sp805_wdt_driver); |
397 | 333 | ||
398 | module_param(nowayout, bool, 0); | ||
399 | MODULE_PARM_DESC(nowayout, | ||
400 | "Set to 1 to keep watchdog running after device release"); | ||
401 | |||
402 | MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>"); | 334 | MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>"); |
403 | MODULE_DESCRIPTION("ARM SP805 Watchdog Driver"); | 335 | MODULE_DESCRIPTION("ARM SP805 Watchdog Driver"); |
404 | MODULE_LICENSE("GPL"); | 336 | MODULE_LICENSE("GPL"); |
405 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||