Root/target/linux/cns21xx/patches-3.3/006-arm-add-fa-watchdog-driver.patch

1--- a/drivers/watchdog/Kconfig
2+++ b/drivers/watchdog/Kconfig
3@@ -343,6 +343,13 @@ config IMX2_WDT
4       To compile this driver as a module, choose M here: the
5       module will be called imx2_wdt.
6 
7+config FA_WATCHDOG
8+ tristate "Faraday watchdog"
9+ depends on ARCH_GEMINI
10+ help
11+ Say Y here if you want support for the built-in watchdog timer
12+ found in some Faraday FA526 based SoCs.
13+
14 # AVR32 Architecture
15 
16 config AT32AP700X_WDT
17--- a/drivers/watchdog/Makefile
18+++ b/drivers/watchdog/Makefile
19@@ -53,6 +53,7 @@ obj-$(CONFIG_STMP3XXX_WATCHDOG) += stmp3
20 obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o
21 obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o
22 obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o
23+obj-$(CONFIG_FA_WATCHDOG) += fa_wdt.o
24 
25 # AVR32 Architecture
26 obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
27--- /dev/null
28+++ b/drivers/watchdog/fa_wdt.c
29@@ -0,0 +1,413 @@
30+/*
31+ * Watchdog driver for SoCs based on the Faraday FA526 core
32+ *
33+ * Copyright (C) 2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
34+ * Copyright (C) 2010-2012 Gabor Juhos <juhosg@openwrt.org>
35+ *
36+ * This program is free software; you can redistribute it and/or modify
37+ * it under the terms of the GNU General Public License version 2 as
38+ * published by the Free Software Foundation.
39+ */
40+
41+#include <linux/kernel.h>
42+#include <linux/module.h>
43+#include <linux/init.h>
44+#include <linux/io.h>
45+#include <linux/fs.h>
46+#include <linux/notifier.h>
47+#include <linux/reboot.h>
48+#include <linux/uaccess.h>
49+#include <linux/miscdevice.h>
50+#include <linux/platform_device.h>
51+#include <linux/watchdog.h>
52+#include <linux/slab.h>
53+#include <linux/fa_wdt.h>
54+
55+#define FA_WDCOUNTER 0x0
56+#define FA_WDLOAD 0x4
57+#define FA_WDRESTART 0x8
58+
59+#define WDRESTART_MAGIC 0x5AB9
60+
61+#define FA_WDCR 0xC
62+
63+#define WDCR_CLOCK_5MHZ (1 << 4)
64+#define WDCR_SYS_RST (1 << 1)
65+#define WDCR_ENABLE (1 << 0)
66+
67+#define WDT_DEFAULT_TIMEOUT 13
68+
69+/* status bits */
70+#define WDT_ACTIVE 0
71+#define WDT_OK_TO_CLOSE 1
72+
73+static unsigned int timeout = WDT_DEFAULT_TIMEOUT;
74+static int nowayout = WATCHDOG_NOWAYOUT;
75+
76+static DEFINE_SPINLOCK(fa_wdt_lock);
77+
78+static struct platform_device *fa_wdt_dev;
79+
80+struct fa_wdt_struct {
81+ struct resource *res;
82+ struct device *dev;
83+ void __iomem *base;
84+ unsigned long status;
85+ unsigned int clock;
86+ unsigned int max_timeout;
87+};
88+
89+static const struct watchdog_info fa_wdt_info = {
90+ .identity = "Faraday watchdog",
91+ .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING |
92+ WDIOF_SETTIMEOUT,
93+};
94+
95+/* Disable the watchdog. */
96+static void fa_wdt_stop(struct fa_wdt_struct *fa_wdt)
97+{
98+ spin_lock(&fa_wdt_lock);
99+
100+ __raw_writel(0, fa_wdt->base + FA_WDCR);
101+
102+ clear_bit(WDT_ACTIVE, &fa_wdt->status);
103+
104+ spin_unlock(&fa_wdt_lock);
105+}
106+
107+/* Service the watchdog */
108+static void fa_wdt_service(struct fa_wdt_struct *fa_wdt)
109+{
110+ __raw_writel(WDRESTART_MAGIC, fa_wdt->base + FA_WDRESTART);
111+}
112+
113+/* Enable and reset the watchdog. */
114+static void fa_wdt_start(struct fa_wdt_struct *fa_wdt)
115+{
116+ spin_lock(&fa_wdt_lock);
117+
118+ __raw_writel(timeout * fa_wdt->clock,
119+ fa_wdt->base + FA_WDLOAD);
120+
121+ fa_wdt_service(fa_wdt);
122+
123+ /* set clock before enabling */
124+ __raw_writel(WDCR_CLOCK_5MHZ | WDCR_SYS_RST,
125+ fa_wdt->base + FA_WDCR);
126+
127+ __raw_writel(WDCR_CLOCK_5MHZ | WDCR_SYS_RST | WDCR_ENABLE,
128+ fa_wdt->base + FA_WDCR);
129+
130+ set_bit(WDT_ACTIVE, &fa_wdt->status);
131+
132+ spin_unlock(&fa_wdt_lock);
133+}
134+
135+/* Watchdog device is opened, and watchdog starts running. */
136+static int fa_wdt_open(struct inode *inode, struct file *file)
137+{
138+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(fa_wdt_dev);
139+
140+ if (test_bit(WDT_ACTIVE, &fa_wdt->status))
141+ return -EBUSY;
142+
143+ file->private_data = fa_wdt;
144+
145+ fa_wdt_start(fa_wdt);
146+
147+ return nonseekable_open(inode, file);
148+}
149+
150+/* Close the watchdog device. */
151+static int fa_wdt_close(struct inode *inode, struct file *file)
152+{
153+ struct fa_wdt_struct *fa_wdt = file->private_data;
154+
155+ /* Disable the watchdog if possible */
156+ if (test_bit(WDT_OK_TO_CLOSE, &fa_wdt->status))
157+ fa_wdt_stop(fa_wdt);
158+ else
159+ dev_warn(fa_wdt->dev, "Device closed unexpectedly - timer will not stop\n");
160+
161+ return 0;
162+}
163+
164+/* Handle commands from user-space. */
165+static long fa_wdt_ioctl(struct file *file, unsigned int cmd,
166+ unsigned long arg)
167+{
168+ struct fa_wdt_struct *fa_wdt = file->private_data;
169+
170+ int value;
171+
172+ switch (cmd) {
173+ case WDIOC_KEEPALIVE:
174+ fa_wdt_service(fa_wdt);
175+ return 0;
176+
177+ case WDIOC_GETSUPPORT:
178+ return copy_to_user((struct watchdog_info *)arg, &fa_wdt_info,
179+ sizeof(fa_wdt_info)) ? -EFAULT : 0;
180+
181+ case WDIOC_SETTIMEOUT:
182+ if (get_user(value, (int *)arg))
183+ return -EFAULT;
184+
185+ if ((value < 1) || (value > fa_wdt->max_timeout))
186+ return -EINVAL;
187+
188+ timeout = value;
189+
190+ /* restart wdt to use new timeout */
191+ fa_wdt_stop(fa_wdt);
192+ fa_wdt_start(fa_wdt);
193+
194+ /* Fall through */
195+ case WDIOC_GETTIMEOUT:
196+ return put_user(timeout, (int *)arg);
197+
198+ case WDIOC_GETTIMELEFT:
199+ value = __raw_readl(fa_wdt->base + FA_WDCOUNTER);
200+ return put_user(value / fa_wdt->clock, (int *)arg);
201+
202+ default:
203+ return -ENOTTY;
204+ }
205+}
206+
207+/* Refresh the watchdog whenever device is written to. */
208+static ssize_t fa_wdt_write(struct file *file, const char *data,
209+ size_t len, loff_t *ppos)
210+{
211+ struct fa_wdt_struct *fa_wdt = file->private_data;
212+
213+ if (len) {
214+ if (!nowayout) {
215+ size_t i;
216+
217+ clear_bit(WDT_OK_TO_CLOSE, &fa_wdt->status);
218+ for (i = 0; i != len; i++) {
219+ char c;
220+
221+ if (get_user(c, data + i))
222+ return -EFAULT;
223+ if (c == 'V')
224+ set_bit(WDT_OK_TO_CLOSE,
225+ &fa_wdt->status);
226+ }
227+ }
228+ fa_wdt_service(fa_wdt);
229+ }
230+
231+ return len;
232+}
233+
234+static int fa_wdt_notify_sys(struct notifier_block *this,
235+ unsigned long code, void *unused)
236+{
237+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(fa_wdt_dev);
238+
239+ if (code == SYS_DOWN || code == SYS_HALT)
240+ fa_wdt_stop(fa_wdt);
241+
242+ return NOTIFY_DONE;
243+}
244+
245+static struct notifier_block fa_wdt_notifier = {
246+ .notifier_call = fa_wdt_notify_sys,
247+};
248+
249+static const struct file_operations fa_wdt_fops = {
250+ .owner = THIS_MODULE,
251+ .llseek = no_llseek,
252+ .unlocked_ioctl = fa_wdt_ioctl,
253+ .open = fa_wdt_open,
254+ .release = fa_wdt_close,
255+ .write = fa_wdt_write,
256+};
257+
258+static struct miscdevice fa_wdt_miscdev = {
259+ .minor = WATCHDOG_MINOR,
260+ .name = "watchdog",
261+ .fops = &fa_wdt_fops,
262+};
263+
264+static void fa_wdt_shutdown(struct platform_device *pdev)
265+{
266+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(pdev);
267+
268+ fa_wdt_stop(fa_wdt);
269+}
270+
271+static int __devinit fa_wdt_probe(struct platform_device *pdev)
272+{
273+ int ret;
274+ int res_size;
275+ struct resource *res;
276+ void __iomem *base;
277+ struct fa_wdt_struct *fa_wdt;
278+ struct fa_wdt_platform_data *pdata;
279+
280+ pdata = pdev->dev.platform_data;
281+ if (!pdata) {
282+ dev_err(&pdev->dev, "no platform data specified\n");
283+ return -EINVAL;
284+ }
285+
286+ if (!pdata->clock) {
287+ dev_err(&pdev->dev, "invalid clock value\n");
288+ return -EINVAL;
289+ }
290+
291+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
292+ if (!res) {
293+ dev_err(&pdev->dev, "can't get device resources\n");
294+ return -ENODEV;
295+ }
296+
297+ res_size = resource_size(res);
298+ if (!request_mem_region(res->start, res_size, res->name)) {
299+ dev_err(&pdev->dev, "can't allocate %d bytes at %d address\n",
300+ res_size, res->start);
301+ return -ENOMEM;
302+ }
303+
304+ base = ioremap(res->start, res_size);
305+ if (!base) {
306+ dev_err(&pdev->dev, "ioremap failed\n");
307+ ret = -EIO;
308+ goto fail0;
309+ }
310+
311+ fa_wdt = kzalloc(sizeof(struct fa_wdt_struct), GFP_KERNEL);
312+ if (!fa_wdt) {
313+ dev_err(&pdev->dev, "can't allocate interface\n");
314+ ret = -ENOMEM;
315+ goto fail1;
316+ }
317+
318+ /* Setup fa_wdt driver structure */
319+ fa_wdt->base = base;
320+ fa_wdt->res = res;
321+ fa_wdt->dev = &pdev->dev;
322+ fa_wdt->clock = pdata->clock;
323+ fa_wdt->max_timeout = 0xffffffffU / pdata->clock;
324+
325+ /* Set up platform driver data */
326+ platform_set_drvdata(pdev, fa_wdt);
327+ fa_wdt_dev = pdev;
328+
329+ if (fa_wdt_miscdev.parent) {
330+ ret = -EBUSY;
331+ goto fail2;
332+ }
333+
334+ ret = register_reboot_notifier(&fa_wdt_notifier);
335+ if (ret)
336+ goto fail2;
337+
338+ fa_wdt_miscdev.parent = &pdev->dev;
339+
340+ ret = misc_register(&fa_wdt_miscdev);
341+ if (ret)
342+ goto fail3;
343+
344+ return 0;
345+
346+fail3:
347+ unregister_reboot_notifier(&fa_wdt_notifier);
348+fail2:
349+ platform_set_drvdata(pdev, NULL);
350+ kfree(fa_wdt);
351+fail1:
352+ iounmap(base);
353+fail0:
354+ release_mem_region(res->start, res_size);
355+
356+ return ret;
357+}
358+
359+static int __devexit fa_wdt_remove(struct platform_device *pdev)
360+{
361+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(pdev);
362+
363+ platform_set_drvdata(pdev, NULL);
364+ misc_deregister(&fa_wdt_miscdev);
365+ unregister_reboot_notifier(&fa_wdt_notifier);
366+ fa_wdt_dev = NULL;
367+ iounmap(fa_wdt->base);
368+ release_mem_region(fa_wdt->res->start, resource_size(fa_wdt->res));
369+
370+ kfree(fa_wdt);
371+
372+ return 0;
373+}
374+
375+#ifdef CONFIG_PM
376+static int fa_wdt_suspend(struct platform_device *pdev, pm_message_t message)
377+{
378+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(pdev);
379+ unsigned int reg;
380+
381+ reg = __raw_readw(fa_wdt->base + FA_WDCR);
382+ reg &= ~(WDCR_WDENABLE);
383+ __raw_writel(reg, fa_wdt->base + FA_WDCR);
384+
385+ return 0;
386+}
387+
388+static int fa_wdt_resume(struct platform_device *pdev)
389+{
390+ struct fa_wdt_struct *fa_wdt = platform_get_drvdata(pdev);
391+ unsigned int reg;
392+
393+ if (fa_wdt->status) {
394+ reg = __raw_readw(fa_wdt->base + FA_WDCR);
395+ reg |= WDCR_WDENABLE;
396+ __raw_writel(reg, fa_wdt->base + FA_WDCR);
397+ }
398+
399+ return 0;
400+}
401+#else
402+#define fa_wdt_suspend NULL
403+#define fa_wdt_resume NULL
404+#endif
405+
406+static struct platform_driver fa_wdt_driver = {
407+ .probe = fa_wdt_probe,
408+ .remove = __devexit_p(fa_wdt_remove),
409+ .shutdown = fa_wdt_shutdown,
410+ .suspend = fa_wdt_suspend,
411+ .resume = fa_wdt_resume,
412+ .driver = {
413+ .name = "fa-wdt",
414+ .owner = THIS_MODULE,
415+ },
416+};
417+
418+static int __init fa_wdt_init(void)
419+{
420+ return platform_driver_probe(&fa_wdt_driver, fa_wdt_probe);
421+}
422+
423+static void __exit fa_wdt_exit(void)
424+{
425+ platform_driver_unregister(&fa_wdt_driver);
426+}
427+
428+module_init(fa_wdt_init);
429+module_exit(fa_wdt_exit);
430+
431+module_param(timeout, uint, 0);
432+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
433+
434+module_param(nowayout, int, 0);
435+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
436+
437+MODULE_AUTHOR("Paulius Zaleckas");
438+MODULE_AUTHOR("Gabor Juhos");
439+MODULE_DESCRIPTION("Watchdog driver for Faraday FA526 based SoCs");
440+MODULE_LICENSE("GPL v2");
441+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
442+MODULE_ALIAS("platform:fa-wdt");
443--- /dev/null
444+++ b/include/linux/fa_wdt.h
445@@ -0,0 +1,13 @@
446+/*
447+ * Platform data definition for the Faraday watchdog driver
448+ */
449+
450+#ifndef _FA_WDT_H
451+#define _FA_WDT_H
452+
453+struct fa_wdt_platform_data {
454+ unsigned int clock;
455+};
456+
457+#endif /* _FA_WDT_H */
458+
459

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