[WATCHDOG] hpwdt.c - fix double includes
[deliverable/linux.git] / drivers / watchdog / omap_wdt.c
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1/*
2 * linux/drivers/char/watchdog/omap_wdt.c
3 *
4 * Watchdog driver for the TI OMAP 16xx & 24xx 32KHz (non-secure) watchdog
5 *
6 * Author: MontaVista Software, Inc.
7 * <gdavis@mvista.com> or <source@mvista.com>
8 *
9 * 2003 (c) MontaVista Software, Inc. This file is licensed under the
10 * terms of the GNU General Public License version 2. This program is
11 * licensed "as is" without any warranty of any kind, whether express
12 * or implied.
13 *
14 * History:
15 *
16 * 20030527: George G. Davis <gdavis@mvista.com>
17 * Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c
18 * (c) Copyright 2000 Oleg Drokin <green@crimea.edu>
19 * Based on SoftDog driver by Alan Cox <alan@redhat.com>
20 *
21 * Copyright (c) 2004 Texas Instruments.
22 * 1. Modified to support OMAP1610 32-KHz watchdog timer
23 * 2. Ported to 2.6 kernel
24 *
25 * Copyright (c) 2005 David Brownell
26 * Use the driver model and standard identifiers; handle bigger timeouts.
27 */
28
29#include <linux/module.h>
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30#include <linux/types.h>
31#include <linux/kernel.h>
32#include <linux/fs.h>
33#include <linux/mm.h>
34#include <linux/miscdevice.h>
35#include <linux/watchdog.h>
36#include <linux/reboot.h>
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37#include <linux/init.h>
38#include <linux/err.h>
39#include <linux/platform_device.h>
40#include <linux/moduleparam.h>
41#include <linux/clk.h>
1977f032 42#include <linux/bitops.h>
7768a13c 43
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44#include </io.h>
45#include <linux/uaccess.h>
46#include <linux/hardware.h>
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47
48#include <asm/arch/prcm.h>
49
50#include "omap_wdt.h"
51
52static unsigned timer_margin;
53module_param(timer_margin, uint, 0);
54MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)");
55
56static int omap_wdt_users;
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57static struct clk *armwdt_ck;
58static struct clk *mpu_wdt_ick;
59static struct clk *mpu_wdt_fck;
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60
61static unsigned int wdt_trgr_pattern = 0x1234;
12b9df7d 62static spinlock_t wdt_lock;
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63
64static void omap_wdt_ping(void)
65{
66 /* wait for posted write to complete */
67 while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08)
68 cpu_relax();
69 wdt_trgr_pattern = ~wdt_trgr_pattern;
70 omap_writel(wdt_trgr_pattern, (OMAP_WATCHDOG_TGR));
71 /* wait for posted write to complete */
72 while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08)
73 cpu_relax();
74 /* reloaded WCRR from WLDR */
75}
76
77static void omap_wdt_enable(void)
78{
79 /* Sequence to enable the watchdog */
80 omap_writel(0xBBBB, OMAP_WATCHDOG_SPR);
81 while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10)
82 cpu_relax();
83 omap_writel(0x4444, OMAP_WATCHDOG_SPR);
84 while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10)
85 cpu_relax();
86}
87
88static void omap_wdt_disable(void)
89{
90 /* sequence required to disable watchdog */
91 omap_writel(0xAAAA, OMAP_WATCHDOG_SPR); /* TIMER_MODE */
92 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10)
93 cpu_relax();
94 omap_writel(0x5555, OMAP_WATCHDOG_SPR); /* TIMER_MODE */
95 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10)
96 cpu_relax();
97}
98
99static void omap_wdt_adjust_timeout(unsigned new_timeout)
100{
101 if (new_timeout < TIMER_MARGIN_MIN)
102 new_timeout = TIMER_MARGIN_DEFAULT;
103 if (new_timeout > TIMER_MARGIN_MAX)
104 new_timeout = TIMER_MARGIN_MAX;
105 timer_margin = new_timeout;
106}
107
108static void omap_wdt_set_timeout(void)
109{
110 u32 pre_margin = GET_WLDR_VAL(timer_margin);
111
112 /* just count up at 32 KHz */
113 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04)
114 cpu_relax();
115 omap_writel(pre_margin, OMAP_WATCHDOG_LDR);
116 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04)
117 cpu_relax();
118}
119
120/*
121 * Allow only one task to hold it open
122 */
123
124static int omap_wdt_open(struct inode *inode, struct file *file)
125{
126 if (test_and_set_bit(1, (unsigned long *)&omap_wdt_users))
127 return -EBUSY;
128
129 if (cpu_is_omap16xx())
130 clk_enable(armwdt_ck); /* Enable the clock */
131
132 if (cpu_is_omap24xx()) {
133 clk_enable(mpu_wdt_ick); /* Enable the interface clock */
134 clk_enable(mpu_wdt_fck); /* Enable the functional clock */
135 }
136
137 /* initialize prescaler */
138 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01)
139 cpu_relax();
140 omap_writel((1 << 5) | (PTV << 2), OMAP_WATCHDOG_CNTRL);
141 while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01)
142 cpu_relax();
143
144 omap_wdt_set_timeout();
145 omap_wdt_enable();
ec9505a7 146 return nonseekable_open(inode, file);
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147}
148
149static int omap_wdt_release(struct inode *inode, struct file *file)
150{
151 /*
152 * Shut off the timer unless NOWAYOUT is defined.
153 */
154#ifndef CONFIG_WATCHDOG_NOWAYOUT
155 omap_wdt_disable();
156
157 if (cpu_is_omap16xx()) {
158 clk_disable(armwdt_ck); /* Disable the clock */
159 clk_put(armwdt_ck);
160 armwdt_ck = NULL;
161 }
162
163 if (cpu_is_omap24xx()) {
164 clk_disable(mpu_wdt_ick); /* Disable the clock */
165 clk_disable(mpu_wdt_fck); /* Disable the clock */
166 clk_put(mpu_wdt_ick);
167 clk_put(mpu_wdt_fck);
168 mpu_wdt_ick = NULL;
169 mpu_wdt_fck = NULL;
170 }
171#else
172 printk(KERN_CRIT "omap_wdt: Unexpected close, not stopping!\n");
173#endif
174 omap_wdt_users = 0;
175 return 0;
176}
177
12b9df7d 178static ssize_t omap_wdt_write(struct file *file, const char __user *data,
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179 size_t len, loff_t *ppos)
180{
181 /* Refresh LOAD_TIME. */
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182 if (len) {
183 spin_lock(&wdt_lock);
7768a13c 184 omap_wdt_ping();
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185 spin_unlock(&wdt_lock);
186 }
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187 return len;
188}
189
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190static long omap_wdt_ioctl(struct file *file, unsigned int cmd,
191 unsigned long arg)
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192{
193 int new_margin;
12b9df7d 194 static const struct watchdog_info ident = {
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195 .identity = "OMAP Watchdog",
196 .options = WDIOF_SETTIMEOUT,
197 .firmware_version = 0,
198 };
199
200 switch (cmd) {
201 default:
1bf1496d 202 return -ENOTTY;
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203 case WDIOC_GETSUPPORT:
204 return copy_to_user((struct watchdog_info __user *)arg, &ident,
205 sizeof(ident));
206 case WDIOC_GETSTATUS:
207 return put_user(0, (int __user *)arg);
208 case WDIOC_GETBOOTSTATUS:
209 if (cpu_is_omap16xx())
210 return put_user(omap_readw(ARM_SYSST),
211 (int __user *)arg);
212 if (cpu_is_omap24xx())
213 return put_user(omap_prcm_get_reset_sources(),
214 (int __user *)arg);
215 case WDIOC_KEEPALIVE:
12b9df7d 216 spin_lock(&wdt_lock);
7768a13c 217 omap_wdt_ping();
12b9df7d 218 spin_unlock(&wdt_lock);
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219 return 0;
220 case WDIOC_SETTIMEOUT:
221 if (get_user(new_margin, (int __user *)arg))
222 return -EFAULT;
223 omap_wdt_adjust_timeout(new_margin);
224
12b9df7d 225 spin_lock(&wdt_lock);
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226 omap_wdt_disable();
227 omap_wdt_set_timeout();
228 omap_wdt_enable();
229
230 omap_wdt_ping();
12b9df7d 231 spin_unlock(&wdt_lock);
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232 /* Fall */
233 case WDIOC_GETTIMEOUT:
234 return put_user(timer_margin, (int __user *)arg);
235 }
236}
237
2b8693c0 238static const struct file_operations omap_wdt_fops = {
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239 .owner = THIS_MODULE,
240 .write = omap_wdt_write,
12b9df7d 241 .unlocked_ioctl = omap_wdt_ioctl,
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242 .open = omap_wdt_open,
243 .release = omap_wdt_release,
244};
245
246static struct miscdevice omap_wdt_miscdev = {
247 .minor = WATCHDOG_MINOR,
248 .name = "watchdog",
249 .fops = &omap_wdt_fops
250};
251
252static int __init omap_wdt_probe(struct platform_device *pdev)
253{
254 struct resource *res, *mem;
255 int ret;
256
257 /* reserve static register mappings */
258 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
259 if (!res)
260 return -ENOENT;
261
262 mem = request_mem_region(res->start, res->end - res->start + 1,
263 pdev->name);
264 if (mem == NULL)
265 return -EBUSY;
266
267 platform_set_drvdata(pdev, mem);
268
269 omap_wdt_users = 0;
270
271 if (cpu_is_omap16xx()) {
272 armwdt_ck = clk_get(&pdev->dev, "armwdt_ck");
273 if (IS_ERR(armwdt_ck)) {
274 ret = PTR_ERR(armwdt_ck);
275 armwdt_ck = NULL;
276 goto fail;
277 }
278 }
279
280 if (cpu_is_omap24xx()) {
281 mpu_wdt_ick = clk_get(&pdev->dev, "mpu_wdt_ick");
282 if (IS_ERR(mpu_wdt_ick)) {
283 ret = PTR_ERR(mpu_wdt_ick);
284 mpu_wdt_ick = NULL;
285 goto fail;
286 }
287 mpu_wdt_fck = clk_get(&pdev->dev, "mpu_wdt_fck");
288 if (IS_ERR(mpu_wdt_fck)) {
289 ret = PTR_ERR(mpu_wdt_fck);
290 mpu_wdt_fck = NULL;
291 goto fail;
292 }
293 }
294
295 omap_wdt_disable();
296 omap_wdt_adjust_timeout(timer_margin);
297
e0b79e0b 298 omap_wdt_miscdev.parent = &pdev->dev;
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299 ret = misc_register(&omap_wdt_miscdev);
300 if (ret)
301 goto fail;
302
303 pr_info("OMAP Watchdog Timer: initial timeout %d sec\n", timer_margin);
304
305 /* autogate OCP interface clock */
306 omap_writel(0x01, OMAP_WATCHDOG_SYS_CONFIG);
307 return 0;
308
309fail:
310 if (armwdt_ck)
311 clk_put(armwdt_ck);
312 if (mpu_wdt_ick)
313 clk_put(mpu_wdt_ick);
314 if (mpu_wdt_fck)
315 clk_put(mpu_wdt_fck);
316 release_resource(mem);
317 return ret;
318}
319
320static void omap_wdt_shutdown(struct platform_device *pdev)
321{
322 omap_wdt_disable();
323}
324
325static int omap_wdt_remove(struct platform_device *pdev)
326{
327 struct resource *mem = platform_get_drvdata(pdev);
328 misc_deregister(&omap_wdt_miscdev);
329 release_resource(mem);
330 if (armwdt_ck)
331 clk_put(armwdt_ck);
332 if (mpu_wdt_ick)
333 clk_put(mpu_wdt_ick);
334 if (mpu_wdt_fck)
335 clk_put(mpu_wdt_fck);
336 return 0;
337}
338
339#ifdef CONFIG_PM
340
341/* REVISIT ... not clear this is the best way to handle system suspend; and
342 * it's very inappropriate for selective device suspend (e.g. suspending this
343 * through sysfs rather than by stopping the watchdog daemon). Also, this
344 * may not play well enough with NOWAYOUT...
345 */
346
347static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state)
348{
349 if (omap_wdt_users)
350 omap_wdt_disable();
351 return 0;
352}
353
354static int omap_wdt_resume(struct platform_device *pdev)
355{
356 if (omap_wdt_users) {
357 omap_wdt_enable();
358 omap_wdt_ping();
359 }
360 return 0;
361}
362
363#else
364#define omap_wdt_suspend NULL
365#define omap_wdt_resume NULL
366#endif
367
368static struct platform_driver omap_wdt_driver = {
369 .probe = omap_wdt_probe,
370 .remove = omap_wdt_remove,
371 .shutdown = omap_wdt_shutdown,
372 .suspend = omap_wdt_suspend,
373 .resume = omap_wdt_resume,
374 .driver = {
375 .owner = THIS_MODULE,
376 .name = "omap_wdt",
377 },
378};
379
380static int __init omap_wdt_init(void)
381{
12b9df7d 382 spin_lock_init(&wdt_lock);
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383 return platform_driver_register(&omap_wdt_driver);
384}
385
386static void __exit omap_wdt_exit(void)
387{
388 platform_driver_unregister(&omap_wdt_driver);
389}
390
391module_init(omap_wdt_init);
392module_exit(omap_wdt_exit);
393
394MODULE_AUTHOR("George G. Davis");
395MODULE_LICENSE("GPL");
396MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
f37d193c 397MODULE_ALIAS("platform:omap_wdt");
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