summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/ni903x_wdt.c
blob: dc67742e9018306a2ea351e83eb310858b0fbf9a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
/*
 * Copyright (C) 2016 National Instruments Corp.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/watchdog.h>

#define NIWD_CONTROL	0x01
#define NIWD_COUNTER2	0x02
#define NIWD_COUNTER1	0x03
#define NIWD_COUNTER0	0x04
#define NIWD_SEED2	0x05
#define NIWD_SEED1	0x06
#define NIWD_SEED0	0x07

#define NIWD_IO_SIZE	0x08

#define NIWD_CONTROL_MODE		0x80
#define NIWD_CONTROL_PROC_RESET		0x20
#define NIWD_CONTROL_PET		0x10
#define NIWD_CONTROL_RUNNING		0x08
#define NIWD_CONTROL_CAPTURECOUNTER	0x04
#define NIWD_CONTROL_RESET		0x02
#define NIWD_CONTROL_ALARM		0x01

#define NIWD_PERIOD_NS		30720
#define NIWD_MIN_TIMEOUT	1
#define NIWD_MAX_TIMEOUT	515
#define NIWD_DEFAULT_TIMEOUT	60

#define NIWD_NAME		"ni903x_wdt"

struct ni903x_wdt {
	struct device *dev;
	u16 io_base;
	struct watchdog_device wdd;
};

static unsigned int timeout;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
		 "Watchdog timeout in seconds. (default="
		 __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")");

static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, S_IRUGO);
MODULE_PARM_DESC(nowayout,
		 "Watchdog cannot be stopped once started (default="
		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

static void ni903x_start(struct ni903x_wdt *wdt)
{
	u8 control = inb(wdt->io_base + NIWD_CONTROL);

	outb(control | NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);
	outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);
}

static int ni903x_wdd_set_timeout(struct watchdog_device *wdd,
				  unsigned int timeout)
{
	struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
	u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS);

	outb(((0x00FF0000 & counter) >> 16), wdt->io_base + NIWD_SEED2);
	outb(((0x0000FF00 & counter) >> 8), wdt->io_base + NIWD_SEED1);
	outb((0x000000FF & counter), wdt->io_base + NIWD_SEED0);

	wdd->timeout = timeout;

	return 0;
}

static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd)
{
	struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
	u8 control, counter0, counter1, counter2;
	u32 counter;

	control = inb(wdt->io_base + NIWD_CONTROL);
	control |= NIWD_CONTROL_CAPTURECOUNTER;
	outb(control, wdt->io_base + NIWD_CONTROL);

	counter2 = inb(wdt->io_base + NIWD_COUNTER2);
	counter1 = inb(wdt->io_base + NIWD_COUNTER1);
	counter0 = inb(wdt->io_base + NIWD_COUNTER0);

	counter = (counter2 << 16) | (counter1 << 8) | counter0;

	return counter / (1000000000 / NIWD_PERIOD_NS);
}

static int ni903x_wdd_ping(struct watchdog_device *wdd)
{
	struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
	u8 control;

	control = inb(wdt->io_base + NIWD_CONTROL);
	outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);

	return 0;
}

static int ni903x_wdd_start(struct watchdog_device *wdd)
{
	struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);

	outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET,
	     wdt->io_base + NIWD_CONTROL);

	ni903x_wdd_set_timeout(wdd, wdd->timeout);
	ni903x_start(wdt);

	return 0;
}

static int ni903x_wdd_stop(struct watchdog_device *wdd)
{
	struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);

	outb(NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);

	return 0;
}

static acpi_status ni903x_resources(struct acpi_resource *res, void *data)
{
	struct ni903x_wdt *wdt = data;
	u16 io_size;

	switch (res->type) {
	case ACPI_RESOURCE_TYPE_IO:
		if (wdt->io_base != 0) {
			dev_err(wdt->dev, "too many IO resources\n");
			return AE_ERROR;
		}

		wdt->io_base = res->data.io.minimum;
		io_size = res->data.io.address_length;

		if (io_size < NIWD_IO_SIZE) {
			dev_err(wdt->dev, "memory region too small\n");
			return AE_ERROR;
		}

		if (!devm_request_region(wdt->dev, wdt->io_base, io_size,
					 NIWD_NAME)) {
			dev_err(wdt->dev, "failed to get memory region\n");
			return AE_ERROR;
		}

		return AE_OK;

	case ACPI_RESOURCE_TYPE_END_TAG:
	default:
		/* Ignore unsupported resources, e.g. IRQ */
		return AE_OK;
	}
}

static const struct watchdog_info ni903x_wdd_info = {
	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
	.identity = "NI Watchdog",
};

static const struct watchdog_ops ni903x_wdd_ops = {
	.owner = THIS_MODULE,
	.start = ni903x_wdd_start,
	.stop = ni903x_wdd_stop,
	.ping = ni903x_wdd_ping,
	.set_timeout = ni903x_wdd_set_timeout,
	.get_timeleft = ni903x_wdd_get_timeleft,
};

static int ni903x_acpi_add(struct acpi_device *device)
{
	struct device *dev = &device->dev;
	struct watchdog_device *wdd;
	struct ni903x_wdt *wdt;
	acpi_status status;
	int ret;

	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
	if (!wdt)
		return -ENOMEM;

	device->driver_data = wdt;
	wdt->dev = dev;

	status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
				     ni903x_resources, wdt);
	if (ACPI_FAILURE(status) || wdt->io_base == 0) {
		dev_err(dev, "failed to get resources\n");
		return -ENODEV;
	}

	wdd = &wdt->wdd;
	wdd->info = &ni903x_wdd_info;
	wdd->ops = &ni903x_wdd_ops;
	wdd->min_timeout = NIWD_MIN_TIMEOUT;
	wdd->max_timeout = NIWD_MAX_TIMEOUT;
	wdd->timeout = NIWD_DEFAULT_TIMEOUT;
	wdd->parent = dev;
	watchdog_set_drvdata(wdd, wdt);
	watchdog_set_nowayout(wdd, nowayout);
	ret = watchdog_init_timeout(wdd, timeout, dev);
	if (ret)
		dev_err(dev, "unable to set timeout value, using default\n");

	ret = watchdog_register_device(wdd);
	if (ret) {
		dev_err(dev, "failed to register watchdog\n");
		return ret;
	}

	/* Switch from boot mode to user mode */
	outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE,
	     wdt->io_base + NIWD_CONTROL);

	dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
		wdt->io_base, timeout, nowayout);

	return 0;
}

static int ni903x_acpi_remove(struct acpi_device *device)
{
	struct ni903x_wdt *wdt = acpi_driver_data(device);

	ni903x_wdd_stop(&wdt->wdd);
	watchdog_unregister_device(&wdt->wdd);

	return 0;
}

static const struct acpi_device_id ni903x_device_ids[] = {
	{"NIC775C", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, ni903x_device_ids);

static struct acpi_driver ni903x_acpi_driver = {
	.name = NIWD_NAME,
	.ids = ni903x_device_ids,
	.ops = {
		.add = ni903x_acpi_add,
		.remove = ni903x_acpi_remove,
	},
};

module_acpi_driver(ni903x_acpi_driver);

MODULE_DESCRIPTION("NI 903x Watchdog");
MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>");
MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud