blob: dc67742e9018306a2ea351e83eb310858b0fbf9a [file] [log] [blame]
Kyle Roeschley70f39972016-02-25 11:28:00 -06001/*
2 * Copyright (C) 2016 National Instruments Corp.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/acpi.h>
16#include <linux/device.h>
17#include <linux/interrupt.h>
18#include <linux/io.h>
19#include <linux/module.h>
20#include <linux/watchdog.h>
21
22#define NIWD_CONTROL 0x01
23#define NIWD_COUNTER2 0x02
24#define NIWD_COUNTER1 0x03
25#define NIWD_COUNTER0 0x04
26#define NIWD_SEED2 0x05
27#define NIWD_SEED1 0x06
28#define NIWD_SEED0 0x07
29
30#define NIWD_IO_SIZE 0x08
31
32#define NIWD_CONTROL_MODE 0x80
33#define NIWD_CONTROL_PROC_RESET 0x20
34#define NIWD_CONTROL_PET 0x10
35#define NIWD_CONTROL_RUNNING 0x08
36#define NIWD_CONTROL_CAPTURECOUNTER 0x04
37#define NIWD_CONTROL_RESET 0x02
38#define NIWD_CONTROL_ALARM 0x01
39
40#define NIWD_PERIOD_NS 30720
41#define NIWD_MIN_TIMEOUT 1
42#define NIWD_MAX_TIMEOUT 515
43#define NIWD_DEFAULT_TIMEOUT 60
44
45#define NIWD_NAME "ni903x_wdt"
46
47struct ni903x_wdt {
48 struct device *dev;
49 u16 io_base;
50 struct watchdog_device wdd;
51};
52
53static unsigned int timeout;
54module_param(timeout, uint, 0);
55MODULE_PARM_DESC(timeout,
56 "Watchdog timeout in seconds. (default="
57 __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")");
58
59static int nowayout = WATCHDOG_NOWAYOUT;
60module_param(nowayout, int, S_IRUGO);
61MODULE_PARM_DESC(nowayout,
62 "Watchdog cannot be stopped once started (default="
63 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
64
65static void ni903x_start(struct ni903x_wdt *wdt)
66{
67 u8 control = inb(wdt->io_base + NIWD_CONTROL);
68
69 outb(control | NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);
70 outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);
71}
72
73static int ni903x_wdd_set_timeout(struct watchdog_device *wdd,
74 unsigned int timeout)
75{
76 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
77 u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS);
78
79 outb(((0x00FF0000 & counter) >> 16), wdt->io_base + NIWD_SEED2);
80 outb(((0x0000FF00 & counter) >> 8), wdt->io_base + NIWD_SEED1);
81 outb((0x000000FF & counter), wdt->io_base + NIWD_SEED0);
82
83 wdd->timeout = timeout;
84
85 return 0;
86}
87
88static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd)
89{
90 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
91 u8 control, counter0, counter1, counter2;
92 u32 counter;
93
94 control = inb(wdt->io_base + NIWD_CONTROL);
95 control |= NIWD_CONTROL_CAPTURECOUNTER;
96 outb(control, wdt->io_base + NIWD_CONTROL);
97
98 counter2 = inb(wdt->io_base + NIWD_COUNTER2);
99 counter1 = inb(wdt->io_base + NIWD_COUNTER1);
100 counter0 = inb(wdt->io_base + NIWD_COUNTER0);
101
102 counter = (counter2 << 16) | (counter1 << 8) | counter0;
103
104 return counter / (1000000000 / NIWD_PERIOD_NS);
105}
106
107static int ni903x_wdd_ping(struct watchdog_device *wdd)
108{
109 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
110 u8 control;
111
112 control = inb(wdt->io_base + NIWD_CONTROL);
113 outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);
114
115 return 0;
116}
117
118static int ni903x_wdd_start(struct watchdog_device *wdd)
119{
120 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
121
122 outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET,
123 wdt->io_base + NIWD_CONTROL);
124
125 ni903x_wdd_set_timeout(wdd, wdd->timeout);
126 ni903x_start(wdt);
127
128 return 0;
129}
130
131static int ni903x_wdd_stop(struct watchdog_device *wdd)
132{
133 struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
134
135 outb(NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);
136
137 return 0;
138}
139
140static acpi_status ni903x_resources(struct acpi_resource *res, void *data)
141{
142 struct ni903x_wdt *wdt = data;
143 u16 io_size;
144
145 switch (res->type) {
146 case ACPI_RESOURCE_TYPE_IO:
147 if (wdt->io_base != 0) {
148 dev_err(wdt->dev, "too many IO resources\n");
149 return AE_ERROR;
150 }
151
152 wdt->io_base = res->data.io.minimum;
153 io_size = res->data.io.address_length;
154
155 if (io_size < NIWD_IO_SIZE) {
156 dev_err(wdt->dev, "memory region too small\n");
157 return AE_ERROR;
158 }
159
160 if (!devm_request_region(wdt->dev, wdt->io_base, io_size,
161 NIWD_NAME)) {
162 dev_err(wdt->dev, "failed to get memory region\n");
163 return AE_ERROR;
164 }
165
166 return AE_OK;
167
168 case ACPI_RESOURCE_TYPE_END_TAG:
169 default:
170 /* Ignore unsupported resources, e.g. IRQ */
171 return AE_OK;
172 }
173}
174
175static const struct watchdog_info ni903x_wdd_info = {
176 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
177 .identity = "NI Watchdog",
178};
179
180static const struct watchdog_ops ni903x_wdd_ops = {
181 .owner = THIS_MODULE,
182 .start = ni903x_wdd_start,
183 .stop = ni903x_wdd_stop,
184 .ping = ni903x_wdd_ping,
185 .set_timeout = ni903x_wdd_set_timeout,
186 .get_timeleft = ni903x_wdd_get_timeleft,
187};
188
189static int ni903x_acpi_add(struct acpi_device *device)
190{
191 struct device *dev = &device->dev;
192 struct watchdog_device *wdd;
193 struct ni903x_wdt *wdt;
194 acpi_status status;
195 int ret;
196
197 wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
198 if (!wdt)
199 return -ENOMEM;
200
201 device->driver_data = wdt;
202 wdt->dev = dev;
203
204 status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
205 ni903x_resources, wdt);
206 if (ACPI_FAILURE(status) || wdt->io_base == 0) {
207 dev_err(dev, "failed to get resources\n");
208 return -ENODEV;
209 }
210
211 wdd = &wdt->wdd;
212 wdd->info = &ni903x_wdd_info;
213 wdd->ops = &ni903x_wdd_ops;
214 wdd->min_timeout = NIWD_MIN_TIMEOUT;
215 wdd->max_timeout = NIWD_MAX_TIMEOUT;
216 wdd->timeout = NIWD_DEFAULT_TIMEOUT;
217 wdd->parent = dev;
218 watchdog_set_drvdata(wdd, wdt);
219 watchdog_set_nowayout(wdd, nowayout);
220 ret = watchdog_init_timeout(wdd, timeout, dev);
221 if (ret)
222 dev_err(dev, "unable to set timeout value, using default\n");
223
224 ret = watchdog_register_device(wdd);
225 if (ret) {
226 dev_err(dev, "failed to register watchdog\n");
227 return ret;
228 }
229
230 /* Switch from boot mode to user mode */
231 outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE,
232 wdt->io_base + NIWD_CONTROL);
233
234 dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
235 wdt->io_base, timeout, nowayout);
236
237 return 0;
238}
239
240static int ni903x_acpi_remove(struct acpi_device *device)
241{
242 struct ni903x_wdt *wdt = acpi_driver_data(device);
243
244 ni903x_wdd_stop(&wdt->wdd);
245 watchdog_unregister_device(&wdt->wdd);
246
247 return 0;
248}
249
250static const struct acpi_device_id ni903x_device_ids[] = {
251 {"NIC775C", 0},
252 {"", 0},
253};
254MODULE_DEVICE_TABLE(acpi, ni903x_device_ids);
255
256static struct acpi_driver ni903x_acpi_driver = {
257 .name = NIWD_NAME,
258 .ids = ni903x_device_ids,
259 .ops = {
260 .add = ni903x_acpi_add,
261 .remove = ni903x_acpi_remove,
262 },
263};
264
265module_acpi_driver(ni903x_acpi_driver);
266
267MODULE_DESCRIPTION("NI 903x Watchdog");
268MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>");
269MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>");
270MODULE_LICENSE("GPL");