1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2016 National Instruments Corp. |
4 | */ |
5 | |
6 | #include <linux/acpi.h> |
7 | #include <linux/device.h> |
8 | #include <linux/interrupt.h> |
9 | #include <linux/io.h> |
10 | #include <linux/module.h> |
11 | #include <linux/watchdog.h> |
12 | |
13 | #define NIWD_CONTROL 0x01 |
14 | #define NIWD_COUNTER2 0x02 |
15 | #define NIWD_COUNTER1 0x03 |
16 | #define NIWD_COUNTER0 0x04 |
17 | #define NIWD_SEED2 0x05 |
18 | #define NIWD_SEED1 0x06 |
19 | #define NIWD_SEED0 0x07 |
20 | |
21 | #define NIWD_IO_SIZE 0x08 |
22 | |
23 | #define NIWD_CONTROL_MODE 0x80 |
24 | #define NIWD_CONTROL_PROC_RESET 0x20 |
25 | #define NIWD_CONTROL_PET 0x10 |
26 | #define NIWD_CONTROL_RUNNING 0x08 |
27 | #define NIWD_CONTROL_CAPTURECOUNTER 0x04 |
28 | #define NIWD_CONTROL_RESET 0x02 |
29 | #define NIWD_CONTROL_ALARM 0x01 |
30 | |
31 | #define NIWD_PERIOD_NS 30720 |
32 | #define NIWD_MIN_TIMEOUT 1 |
33 | #define NIWD_MAX_TIMEOUT 515 |
34 | #define NIWD_DEFAULT_TIMEOUT 60 |
35 | |
36 | #define NIWD_NAME "ni903x_wdt" |
37 | |
38 | struct ni903x_wdt { |
39 | struct device *dev; |
40 | u16 io_base; |
41 | struct watchdog_device wdd; |
42 | }; |
43 | |
44 | static unsigned int timeout; |
45 | module_param(timeout, uint, 0); |
46 | MODULE_PARM_DESC(timeout, |
47 | "Watchdog timeout in seconds. (default=" |
48 | __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")" ); |
49 | |
50 | static int nowayout = WATCHDOG_NOWAYOUT; |
51 | module_param(nowayout, int, S_IRUGO); |
52 | MODULE_PARM_DESC(nowayout, |
53 | "Watchdog cannot be stopped once started (default=" |
54 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")" ); |
55 | |
56 | static void ni903x_start(struct ni903x_wdt *wdt) |
57 | { |
58 | u8 control = inb(port: wdt->io_base + NIWD_CONTROL); |
59 | |
60 | outb(value: control | NIWD_CONTROL_RESET, port: wdt->io_base + NIWD_CONTROL); |
61 | outb(value: control | NIWD_CONTROL_PET, port: wdt->io_base + NIWD_CONTROL); |
62 | } |
63 | |
64 | static int ni903x_wdd_set_timeout(struct watchdog_device *wdd, |
65 | unsigned int timeout) |
66 | { |
67 | struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); |
68 | u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS); |
69 | |
70 | outb(value: ((0x00FF0000 & counter) >> 16), port: wdt->io_base + NIWD_SEED2); |
71 | outb(value: ((0x0000FF00 & counter) >> 8), port: wdt->io_base + NIWD_SEED1); |
72 | outb(value: (0x000000FF & counter), port: wdt->io_base + NIWD_SEED0); |
73 | |
74 | wdd->timeout = timeout; |
75 | |
76 | return 0; |
77 | } |
78 | |
79 | static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd) |
80 | { |
81 | struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); |
82 | u8 control, counter0, counter1, counter2; |
83 | u32 counter; |
84 | |
85 | control = inb(port: wdt->io_base + NIWD_CONTROL); |
86 | control |= NIWD_CONTROL_CAPTURECOUNTER; |
87 | outb(value: control, port: wdt->io_base + NIWD_CONTROL); |
88 | |
89 | counter2 = inb(port: wdt->io_base + NIWD_COUNTER2); |
90 | counter1 = inb(port: wdt->io_base + NIWD_COUNTER1); |
91 | counter0 = inb(port: wdt->io_base + NIWD_COUNTER0); |
92 | |
93 | counter = (counter2 << 16) | (counter1 << 8) | counter0; |
94 | |
95 | return counter / (1000000000 / NIWD_PERIOD_NS); |
96 | } |
97 | |
98 | static int ni903x_wdd_ping(struct watchdog_device *wdd) |
99 | { |
100 | struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); |
101 | u8 control; |
102 | |
103 | control = inb(port: wdt->io_base + NIWD_CONTROL); |
104 | outb(value: control | NIWD_CONTROL_PET, port: wdt->io_base + NIWD_CONTROL); |
105 | |
106 | return 0; |
107 | } |
108 | |
109 | static int ni903x_wdd_start(struct watchdog_device *wdd) |
110 | { |
111 | struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); |
112 | |
113 | outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET, |
114 | port: wdt->io_base + NIWD_CONTROL); |
115 | |
116 | ni903x_wdd_set_timeout(wdd, timeout: wdd->timeout); |
117 | ni903x_start(wdt); |
118 | |
119 | return 0; |
120 | } |
121 | |
122 | static int ni903x_wdd_stop(struct watchdog_device *wdd) |
123 | { |
124 | struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd); |
125 | |
126 | outb(NIWD_CONTROL_RESET, port: wdt->io_base + NIWD_CONTROL); |
127 | |
128 | return 0; |
129 | } |
130 | |
131 | static acpi_status ni903x_resources(struct acpi_resource *res, void *data) |
132 | { |
133 | struct ni903x_wdt *wdt = data; |
134 | u16 io_size; |
135 | |
136 | switch (res->type) { |
137 | case ACPI_RESOURCE_TYPE_IO: |
138 | if (wdt->io_base != 0) { |
139 | dev_err(wdt->dev, "too many IO resources\n" ); |
140 | return AE_ERROR; |
141 | } |
142 | |
143 | wdt->io_base = res->data.io.minimum; |
144 | io_size = res->data.io.address_length; |
145 | |
146 | if (io_size < NIWD_IO_SIZE) { |
147 | dev_err(wdt->dev, "memory region too small\n" ); |
148 | return AE_ERROR; |
149 | } |
150 | |
151 | if (!devm_request_region(wdt->dev, wdt->io_base, io_size, |
152 | NIWD_NAME)) { |
153 | dev_err(wdt->dev, "failed to get memory region\n" ); |
154 | return AE_ERROR; |
155 | } |
156 | |
157 | return AE_OK; |
158 | |
159 | case ACPI_RESOURCE_TYPE_END_TAG: |
160 | default: |
161 | /* Ignore unsupported resources, e.g. IRQ */ |
162 | return AE_OK; |
163 | } |
164 | } |
165 | |
166 | static const struct watchdog_info ni903x_wdd_info = { |
167 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, |
168 | .identity = "NI Watchdog" , |
169 | }; |
170 | |
171 | static const struct watchdog_ops ni903x_wdd_ops = { |
172 | .owner = THIS_MODULE, |
173 | .start = ni903x_wdd_start, |
174 | .stop = ni903x_wdd_stop, |
175 | .ping = ni903x_wdd_ping, |
176 | .set_timeout = ni903x_wdd_set_timeout, |
177 | .get_timeleft = ni903x_wdd_get_timeleft, |
178 | }; |
179 | |
180 | static int ni903x_acpi_add(struct acpi_device *device) |
181 | { |
182 | struct device *dev = &device->dev; |
183 | struct watchdog_device *wdd; |
184 | struct ni903x_wdt *wdt; |
185 | acpi_status status; |
186 | int ret; |
187 | |
188 | wdt = devm_kzalloc(dev, size: sizeof(*wdt), GFP_KERNEL); |
189 | if (!wdt) |
190 | return -ENOMEM; |
191 | |
192 | device->driver_data = wdt; |
193 | wdt->dev = dev; |
194 | |
195 | status = acpi_walk_resources(device: device->handle, METHOD_NAME__CRS, |
196 | user_function: ni903x_resources, context: wdt); |
197 | if (ACPI_FAILURE(status) || wdt->io_base == 0) { |
198 | dev_err(dev, "failed to get resources\n" ); |
199 | return -ENODEV; |
200 | } |
201 | |
202 | wdd = &wdt->wdd; |
203 | wdd->info = &ni903x_wdd_info; |
204 | wdd->ops = &ni903x_wdd_ops; |
205 | wdd->min_timeout = NIWD_MIN_TIMEOUT; |
206 | wdd->max_timeout = NIWD_MAX_TIMEOUT; |
207 | wdd->timeout = NIWD_DEFAULT_TIMEOUT; |
208 | wdd->parent = dev; |
209 | watchdog_set_drvdata(wdd, data: wdt); |
210 | watchdog_set_nowayout(wdd, nowayout); |
211 | watchdog_init_timeout(wdd, timeout_parm: timeout, dev); |
212 | |
213 | ret = watchdog_register_device(wdd); |
214 | if (ret) |
215 | return ret; |
216 | |
217 | /* Switch from boot mode to user mode */ |
218 | outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE, |
219 | port: wdt->io_base + NIWD_CONTROL); |
220 | |
221 | dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n" , |
222 | wdt->io_base, timeout, nowayout); |
223 | |
224 | return 0; |
225 | } |
226 | |
227 | static void ni903x_acpi_remove(struct acpi_device *device) |
228 | { |
229 | struct ni903x_wdt *wdt = acpi_driver_data(d: device); |
230 | |
231 | ni903x_wdd_stop(wdd: &wdt->wdd); |
232 | watchdog_unregister_device(&wdt->wdd); |
233 | } |
234 | |
235 | static const struct acpi_device_id ni903x_device_ids[] = { |
236 | {"NIC775C" , 0}, |
237 | {"" , 0}, |
238 | }; |
239 | MODULE_DEVICE_TABLE(acpi, ni903x_device_ids); |
240 | |
241 | static struct acpi_driver ni903x_acpi_driver = { |
242 | .name = NIWD_NAME, |
243 | .ids = ni903x_device_ids, |
244 | .ops = { |
245 | .add = ni903x_acpi_add, |
246 | .remove = ni903x_acpi_remove, |
247 | }, |
248 | }; |
249 | |
250 | module_acpi_driver(ni903x_acpi_driver); |
251 | |
252 | MODULE_DESCRIPTION("NI 903x Watchdog" ); |
253 | MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>" ); |
254 | MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>" ); |
255 | MODULE_LICENSE("GPL" ); |
256 | |