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1/***************************************************************************
2 * Copyright (C) 2010-2011 Hans de Goede <hdegoede@redhat.com> *
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 * You should have received a copy of the GNU General Public License *
15 * along with this program; if not, write to the *
16 * Free Software Foundation, Inc., *
17 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
18 ***************************************************************************/
19
20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22#include <linux/module.h>
23#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/err.h>
26#include <linux/io.h>
27#include <linux/acpi.h>
28#include <linux/delay.h>
29#include "sch56xx-common.h"
30
31#define SIO_SCH56XX_LD_EM 0x0C /* Embedded uController Logical Dev */
32#define SIO_UNLOCK_KEY 0x55 /* Key to enable Super-I/O */
33#define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */
34
35#define SIO_REG_LDSEL 0x07 /* Logical device select */
36#define SIO_REG_DEVID 0x20 /* Device ID */
37#define SIO_REG_ENABLE 0x30 /* Logical device enable */
38#define SIO_REG_ADDR 0x66 /* Logical device address (2 bytes) */
39
40#define SIO_SCH5627_ID 0xC6 /* Chipset ID */
41#define SIO_SCH5636_ID 0xC7 /* Chipset ID */
42
43#define REGION_LENGTH 9
44
45#define SCH56XX_CMD_READ 0x02
46#define SCH56XX_CMD_WRITE 0x03
47
48static struct platform_device *sch56xx_pdev;
49
50/* Super I/O functions */
51static inline int superio_inb(int base, int reg)
52{
53 outb(reg, base);
54 return inb(base + 1);
55}
56
57static inline int superio_enter(int base)
58{
59 /* Don't step on other drivers' I/O space by accident */
60 if (!request_muxed_region(base, 2, "sch56xx")) {
61 pr_err("I/O address 0x%04x already in use\n", base);
62 return -EBUSY;
63 }
64
65 outb(SIO_UNLOCK_KEY, base);
66
67 return 0;
68}
69
70static inline void superio_select(int base, int ld)
71{
72 outb(SIO_REG_LDSEL, base);
73 outb(ld, base + 1);
74}
75
76static inline void superio_exit(int base)
77{
78 outb(SIO_LOCK_KEY, base);
79 release_region(base, 2);
80}
81
82static int sch56xx_send_cmd(u16 addr, u8 cmd, u16 reg, u8 v)
83{
84 u8 val;
85 int i;
86 /*
87 * According to SMSC for the commands we use the maximum time for
88 * the EM to respond is 15 ms, but testing shows in practice it
89 * responds within 15-32 reads, so we first busy poll, and if
90 * that fails sleep a bit and try again until we are way past
91 * the 15 ms maximum response time.
92 */
93 const int max_busy_polls = 64;
94 const int max_lazy_polls = 32;
95
96 /* (Optional) Write-Clear the EC to Host Mailbox Register */
97 val = inb(addr + 1);
98 outb(val, addr + 1);
99
100 /* Set Mailbox Address Pointer to first location in Region 1 */
101 outb(0x00, addr + 2);
102 outb(0x80, addr + 3);
103
104 /* Write Request Packet Header */
105 outb(cmd, addr + 4); /* VREG Access Type read:0x02 write:0x03 */
106 outb(0x01, addr + 5); /* # of Entries: 1 Byte (8-bit) */
107 outb(0x04, addr + 2); /* Mailbox AP to first data entry loc. */
108
109 /* Write Value field */
110 if (cmd == SCH56XX_CMD_WRITE)
111 outb(v, addr + 4);
112
113 /* Write Address field */
114 outb(reg & 0xff, addr + 6);
115 outb(reg >> 8, addr + 7);
116
117 /* Execute the Random Access Command */
118 outb(0x01, addr); /* Write 01h to the Host-to-EC register */
119
120 /* EM Interface Polling "Algorithm" */
121 for (i = 0; i < max_busy_polls + max_lazy_polls; i++) {
122 if (i >= max_busy_polls)
123 msleep(1);
124 /* Read Interrupt source Register */
125 val = inb(addr + 8);
126 /* Write Clear the interrupt source bits */
127 if (val)
128 outb(val, addr + 8);
129 /* Command Completed ? */
130 if (val & 0x01)
131 break;
132 }
133 if (i == max_busy_polls + max_lazy_polls) {
134 pr_err("Max retries exceeded reading virtual "
135 "register 0x%04hx (%d)\n", reg, 1);
136 return -EIO;
137 }
138
139 /*
140 * According to SMSC we may need to retry this, but sofar I've always
141 * seen this succeed in 1 try.
142 */
143 for (i = 0; i < max_busy_polls; i++) {
144 /* Read EC-to-Host Register */
145 val = inb(addr + 1);
146 /* Command Completed ? */
147 if (val == 0x01)
148 break;
149
150 if (i == 0)
151 pr_warn("EC reports: 0x%02x reading virtual register "
152 "0x%04hx\n", (unsigned int)val, reg);
153 }
154 if (i == max_busy_polls) {
155 pr_err("Max retries exceeded reading virtual "
156 "register 0x%04hx (%d)\n", reg, 2);
157 return -EIO;
158 }
159
160 /*
161 * According to the SMSC app note we should now do:
162 *
163 * Set Mailbox Address Pointer to first location in Region 1 *
164 * outb(0x00, addr + 2);
165 * outb(0x80, addr + 3);
166 *
167 * But if we do that things don't work, so let's not.
168 */
169
170 /* Read Value field */
171 if (cmd == SCH56XX_CMD_READ)
172 return inb(addr + 4);
173
174 return 0;
175}
176
177int sch56xx_read_virtual_reg(u16 addr, u16 reg)
178{
179 return sch56xx_send_cmd(addr, SCH56XX_CMD_READ, reg, 0);
180}
181EXPORT_SYMBOL(sch56xx_read_virtual_reg);
182
183int sch56xx_write_virtual_reg(u16 addr, u16 reg, u8 val)
184{
185 return sch56xx_send_cmd(addr, SCH56XX_CMD_WRITE, reg, val);
186}
187EXPORT_SYMBOL(sch56xx_write_virtual_reg);
188
189int sch56xx_read_virtual_reg16(u16 addr, u16 reg)
190{
191 int lsb, msb;
192
193 /* Read LSB first, this will cause the matching MSB to be latched */
194 lsb = sch56xx_read_virtual_reg(addr, reg);
195 if (lsb < 0)
196 return lsb;
197
198 msb = sch56xx_read_virtual_reg(addr, reg + 1);
199 if (msb < 0)
200 return msb;
201
202 return lsb | (msb << 8);
203}
204EXPORT_SYMBOL(sch56xx_read_virtual_reg16);
205
206int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
207 int high_nibble)
208{
209 int msb, lsn;
210
211 /* Read MSB first, this will cause the matching LSN to be latched */
212 msb = sch56xx_read_virtual_reg(addr, msb_reg);
213 if (msb < 0)
214 return msb;
215
216 lsn = sch56xx_read_virtual_reg(addr, lsn_reg);
217 if (lsn < 0)
218 return lsn;
219
220 if (high_nibble)
221 return (msb << 4) | (lsn >> 4);
222 else
223 return (msb << 4) | (lsn & 0x0f);
224}
225EXPORT_SYMBOL(sch56xx_read_virtual_reg12);
226
227static int __init sch56xx_find(int sioaddr, unsigned short *address,
228 const char **name)
229{
230 u8 devid;
231 int err;
232
233 err = superio_enter(sioaddr);
234 if (err)
235 return err;
236
237 devid = superio_inb(sioaddr, SIO_REG_DEVID);
238 switch (devid) {
239 case SIO_SCH5627_ID:
240 *name = "sch5627";
241 break;
242 case SIO_SCH5636_ID:
243 *name = "sch5636";
244 break;
245 default:
246 pr_debug("Unsupported device id: 0x%02x\n",
247 (unsigned int)devid);
248 err = -ENODEV;
249 goto exit;
250 }
251
252 superio_select(sioaddr, SIO_SCH56XX_LD_EM);
253
254 if (!(superio_inb(sioaddr, SIO_REG_ENABLE) & 0x01)) {
255 pr_warn("Device not activated\n");
256 err = -ENODEV;
257 goto exit;
258 }
259
260 /*
261 * Warning the order of the low / high byte is the other way around
262 * as on most other superio devices!!
263 */
264 *address = superio_inb(sioaddr, SIO_REG_ADDR) |
265 superio_inb(sioaddr, SIO_REG_ADDR + 1) << 8;
266 if (*address == 0) {
267 pr_warn("Base address not set\n");
268 err = -ENODEV;
269 goto exit;
270 }
271
272exit:
273 superio_exit(sioaddr);
274 return err;
275}
276
277static int __init sch56xx_device_add(unsigned short address, const char *name)
278{
279 struct resource res = {
280 .start = address,
281 .end = address + REGION_LENGTH - 1,
282 .flags = IORESOURCE_IO,
283 };
284 int err;
285
286 sch56xx_pdev = platform_device_alloc(name, address);
287 if (!sch56xx_pdev)
288 return -ENOMEM;
289
290 res.name = sch56xx_pdev->name;
291 err = acpi_check_resource_conflict(&res);
292 if (err)
293 goto exit_device_put;
294
295 err = platform_device_add_resources(sch56xx_pdev, &res, 1);
296 if (err) {
297 pr_err("Device resource addition failed\n");
298 goto exit_device_put;
299 }
300
301 err = platform_device_add(sch56xx_pdev);
302 if (err) {
303 pr_err("Device addition failed\n");
304 goto exit_device_put;
305 }
306
307 return 0;
308
309exit_device_put:
310 platform_device_put(sch56xx_pdev);
311
312 return err;
313}
314
315static int __init sch56xx_init(void)
316{
317 int err;
318 unsigned short address;
319 const char *name;
320
321 err = sch56xx_find(0x4e, &address, &name);
322 if (err)
323 err = sch56xx_find(0x2e, &address, &name);
324 if (err)
325 return err;
326
327 return sch56xx_device_add(address, name);
328}
329
330static void __exit sch56xx_exit(void)
331{
332 platform_device_unregister(sch56xx_pdev);
333}
334
335MODULE_DESCRIPTION("SMSC SCH56xx Hardware Monitoring Common Code");
336MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
337MODULE_LICENSE("GPL");
338
339module_init(sch56xx_init);
340module_exit(sch56xx_exit);
1/***************************************************************************
2 * Copyright (C) 2010-2012 Hans de Goede <hdegoede@redhat.com> *
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 * You should have received a copy of the GNU General Public License *
15 * along with this program; if not, write to the *
16 * Free Software Foundation, Inc., *
17 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
18 ***************************************************************************/
19
20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22#include <linux/module.h>
23#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/err.h>
26#include <linux/io.h>
27#include <linux/acpi.h>
28#include <linux/delay.h>
29#include <linux/fs.h>
30#include <linux/watchdog.h>
31#include <linux/miscdevice.h>
32#include <linux/uaccess.h>
33#include <linux/slab.h>
34#include "sch56xx-common.h"
35
36/* Insmod parameters */
37static int nowayout = WATCHDOG_NOWAYOUT;
38module_param(nowayout, int, 0);
39MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
40 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
41
42#define SIO_SCH56XX_LD_EM 0x0C /* Embedded uController Logical Dev */
43#define SIO_UNLOCK_KEY 0x55 /* Key to enable Super-I/O */
44#define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */
45
46#define SIO_REG_LDSEL 0x07 /* Logical device select */
47#define SIO_REG_DEVID 0x20 /* Device ID */
48#define SIO_REG_ENABLE 0x30 /* Logical device enable */
49#define SIO_REG_ADDR 0x66 /* Logical device address (2 bytes) */
50
51#define SIO_SCH5627_ID 0xC6 /* Chipset ID */
52#define SIO_SCH5636_ID 0xC7 /* Chipset ID */
53
54#define REGION_LENGTH 10
55
56#define SCH56XX_CMD_READ 0x02
57#define SCH56XX_CMD_WRITE 0x03
58
59/* Watchdog registers */
60#define SCH56XX_REG_WDOG_PRESET 0x58B
61#define SCH56XX_REG_WDOG_CONTROL 0x58C
62#define SCH56XX_WDOG_TIME_BASE_SEC 0x01
63#define SCH56XX_REG_WDOG_OUTPUT_ENABLE 0x58E
64#define SCH56XX_WDOG_OUTPUT_ENABLE 0x02
65
66struct sch56xx_watchdog_data {
67 u16 addr;
68 struct mutex *io_lock;
69 struct watchdog_info wdinfo;
70 struct watchdog_device wddev;
71 u8 watchdog_preset;
72 u8 watchdog_control;
73 u8 watchdog_output_enable;
74};
75
76static struct platform_device *sch56xx_pdev;
77
78/* Super I/O functions */
79static inline int superio_inb(int base, int reg)
80{
81 outb(reg, base);
82 return inb(base + 1);
83}
84
85static inline int superio_enter(int base)
86{
87 /* Don't step on other drivers' I/O space by accident */
88 if (!request_muxed_region(base, 2, "sch56xx")) {
89 pr_err("I/O address 0x%04x already in use\n", base);
90 return -EBUSY;
91 }
92
93 outb(SIO_UNLOCK_KEY, base);
94
95 return 0;
96}
97
98static inline void superio_select(int base, int ld)
99{
100 outb(SIO_REG_LDSEL, base);
101 outb(ld, base + 1);
102}
103
104static inline void superio_exit(int base)
105{
106 outb(SIO_LOCK_KEY, base);
107 release_region(base, 2);
108}
109
110static int sch56xx_send_cmd(u16 addr, u8 cmd, u16 reg, u8 v)
111{
112 u8 val;
113 int i;
114 /*
115 * According to SMSC for the commands we use the maximum time for
116 * the EM to respond is 15 ms, but testing shows in practice it
117 * responds within 15-32 reads, so we first busy poll, and if
118 * that fails sleep a bit and try again until we are way past
119 * the 15 ms maximum response time.
120 */
121 const int max_busy_polls = 64;
122 const int max_lazy_polls = 32;
123
124 /* (Optional) Write-Clear the EC to Host Mailbox Register */
125 val = inb(addr + 1);
126 outb(val, addr + 1);
127
128 /* Set Mailbox Address Pointer to first location in Region 1 */
129 outb(0x00, addr + 2);
130 outb(0x80, addr + 3);
131
132 /* Write Request Packet Header */
133 outb(cmd, addr + 4); /* VREG Access Type read:0x02 write:0x03 */
134 outb(0x01, addr + 5); /* # of Entries: 1 Byte (8-bit) */
135 outb(0x04, addr + 2); /* Mailbox AP to first data entry loc. */
136
137 /* Write Value field */
138 if (cmd == SCH56XX_CMD_WRITE)
139 outb(v, addr + 4);
140
141 /* Write Address field */
142 outb(reg & 0xff, addr + 6);
143 outb(reg >> 8, addr + 7);
144
145 /* Execute the Random Access Command */
146 outb(0x01, addr); /* Write 01h to the Host-to-EC register */
147
148 /* EM Interface Polling "Algorithm" */
149 for (i = 0; i < max_busy_polls + max_lazy_polls; i++) {
150 if (i >= max_busy_polls)
151 msleep(1);
152 /* Read Interrupt source Register */
153 val = inb(addr + 8);
154 /* Write Clear the interrupt source bits */
155 if (val)
156 outb(val, addr + 8);
157 /* Command Completed ? */
158 if (val & 0x01)
159 break;
160 }
161 if (i == max_busy_polls + max_lazy_polls) {
162 pr_err("Max retries exceeded reading virtual register 0x%04hx (%d)\n",
163 reg, 1);
164 return -EIO;
165 }
166
167 /*
168 * According to SMSC we may need to retry this, but sofar I've always
169 * seen this succeed in 1 try.
170 */
171 for (i = 0; i < max_busy_polls; i++) {
172 /* Read EC-to-Host Register */
173 val = inb(addr + 1);
174 /* Command Completed ? */
175 if (val == 0x01)
176 break;
177
178 if (i == 0)
179 pr_warn("EC reports: 0x%02x reading virtual register 0x%04hx\n",
180 (unsigned int)val, reg);
181 }
182 if (i == max_busy_polls) {
183 pr_err("Max retries exceeded reading virtual register 0x%04hx (%d)\n",
184 reg, 2);
185 return -EIO;
186 }
187
188 /*
189 * According to the SMSC app note we should now do:
190 *
191 * Set Mailbox Address Pointer to first location in Region 1 *
192 * outb(0x00, addr + 2);
193 * outb(0x80, addr + 3);
194 *
195 * But if we do that things don't work, so let's not.
196 */
197
198 /* Read Value field */
199 if (cmd == SCH56XX_CMD_READ)
200 return inb(addr + 4);
201
202 return 0;
203}
204
205int sch56xx_read_virtual_reg(u16 addr, u16 reg)
206{
207 return sch56xx_send_cmd(addr, SCH56XX_CMD_READ, reg, 0);
208}
209EXPORT_SYMBOL(sch56xx_read_virtual_reg);
210
211int sch56xx_write_virtual_reg(u16 addr, u16 reg, u8 val)
212{
213 return sch56xx_send_cmd(addr, SCH56XX_CMD_WRITE, reg, val);
214}
215EXPORT_SYMBOL(sch56xx_write_virtual_reg);
216
217int sch56xx_read_virtual_reg16(u16 addr, u16 reg)
218{
219 int lsb, msb;
220
221 /* Read LSB first, this will cause the matching MSB to be latched */
222 lsb = sch56xx_read_virtual_reg(addr, reg);
223 if (lsb < 0)
224 return lsb;
225
226 msb = sch56xx_read_virtual_reg(addr, reg + 1);
227 if (msb < 0)
228 return msb;
229
230 return lsb | (msb << 8);
231}
232EXPORT_SYMBOL(sch56xx_read_virtual_reg16);
233
234int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
235 int high_nibble)
236{
237 int msb, lsn;
238
239 /* Read MSB first, this will cause the matching LSN to be latched */
240 msb = sch56xx_read_virtual_reg(addr, msb_reg);
241 if (msb < 0)
242 return msb;
243
244 lsn = sch56xx_read_virtual_reg(addr, lsn_reg);
245 if (lsn < 0)
246 return lsn;
247
248 if (high_nibble)
249 return (msb << 4) | (lsn >> 4);
250 else
251 return (msb << 4) | (lsn & 0x0f);
252}
253EXPORT_SYMBOL(sch56xx_read_virtual_reg12);
254
255/*
256 * Watchdog routines
257 */
258
259static int watchdog_set_timeout(struct watchdog_device *wddev,
260 unsigned int timeout)
261{
262 struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
263 unsigned int resolution;
264 u8 control;
265 int ret;
266
267 /* 1 second or 60 second resolution? */
268 if (timeout <= 255)
269 resolution = 1;
270 else
271 resolution = 60;
272
273 if (timeout < resolution || timeout > (resolution * 255))
274 return -EINVAL;
275
276 if (resolution == 1)
277 control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC;
278 else
279 control = data->watchdog_control & ~SCH56XX_WDOG_TIME_BASE_SEC;
280
281 if (data->watchdog_control != control) {
282 mutex_lock(data->io_lock);
283 ret = sch56xx_write_virtual_reg(data->addr,
284 SCH56XX_REG_WDOG_CONTROL,
285 control);
286 mutex_unlock(data->io_lock);
287 if (ret)
288 return ret;
289
290 data->watchdog_control = control;
291 }
292
293 /*
294 * Remember new timeout value, but do not write as that (re)starts
295 * the watchdog countdown.
296 */
297 data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
298 wddev->timeout = data->watchdog_preset * resolution;
299
300 return 0;
301}
302
303static int watchdog_start(struct watchdog_device *wddev)
304{
305 struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
306 int ret;
307 u8 val;
308
309 /*
310 * The sch56xx's watchdog cannot really be started / stopped
311 * it is always running, but we can avoid the timer expiring
312 * from causing a system reset by clearing the output enable bit.
313 *
314 * The sch56xx's watchdog will set the watchdog event bit, bit 0
315 * of the second interrupt source register (at base-address + 9),
316 * when the timer expires.
317 *
318 * This will only cause a system reset if the 0-1 flank happens when
319 * output enable is true. Setting output enable after the flank will
320 * not cause a reset, nor will the timer expiring a second time.
321 * This means we must clear the watchdog event bit in case it is set.
322 *
323 * The timer may still be running (after a recent watchdog_stop) and
324 * mere milliseconds away from expiring, so the timer must be reset
325 * first!
326 */
327
328 mutex_lock(data->io_lock);
329
330 /* 1. Reset the watchdog countdown counter */
331 ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
332 data->watchdog_preset);
333 if (ret)
334 goto leave;
335
336 /* 2. Enable output */
337 val = data->watchdog_output_enable | SCH56XX_WDOG_OUTPUT_ENABLE;
338 ret = sch56xx_write_virtual_reg(data->addr,
339 SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
340 if (ret)
341 goto leave;
342
343 data->watchdog_output_enable = val;
344
345 /* 3. Clear the watchdog event bit if set */
346 val = inb(data->addr + 9);
347 if (val & 0x01)
348 outb(0x01, data->addr + 9);
349
350leave:
351 mutex_unlock(data->io_lock);
352 return ret;
353}
354
355static int watchdog_trigger(struct watchdog_device *wddev)
356{
357 struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
358 int ret;
359
360 /* Reset the watchdog countdown counter */
361 mutex_lock(data->io_lock);
362 ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
363 data->watchdog_preset);
364 mutex_unlock(data->io_lock);
365
366 return ret;
367}
368
369static int watchdog_stop(struct watchdog_device *wddev)
370{
371 struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
372 int ret = 0;
373 u8 val;
374
375 val = data->watchdog_output_enable & ~SCH56XX_WDOG_OUTPUT_ENABLE;
376 mutex_lock(data->io_lock);
377 ret = sch56xx_write_virtual_reg(data->addr,
378 SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
379 mutex_unlock(data->io_lock);
380 if (ret)
381 return ret;
382
383 data->watchdog_output_enable = val;
384 return 0;
385}
386
387static const struct watchdog_ops watchdog_ops = {
388 .owner = THIS_MODULE,
389 .start = watchdog_start,
390 .stop = watchdog_stop,
391 .ping = watchdog_trigger,
392 .set_timeout = watchdog_set_timeout,
393};
394
395struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
396 u16 addr, u32 revision, struct mutex *io_lock, int check_enabled)
397{
398 struct sch56xx_watchdog_data *data;
399 int err, control, output_enable;
400
401 /* Cache the watchdog registers */
402 mutex_lock(io_lock);
403 control =
404 sch56xx_read_virtual_reg(addr, SCH56XX_REG_WDOG_CONTROL);
405 output_enable =
406 sch56xx_read_virtual_reg(addr, SCH56XX_REG_WDOG_OUTPUT_ENABLE);
407 mutex_unlock(io_lock);
408
409 if (control < 0)
410 return NULL;
411 if (output_enable < 0)
412 return NULL;
413 if (check_enabled && !(output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)) {
414 pr_warn("Watchdog not enabled by BIOS, not registering\n");
415 return NULL;
416 }
417
418 data = kzalloc(sizeof(struct sch56xx_watchdog_data), GFP_KERNEL);
419 if (!data)
420 return NULL;
421
422 data->addr = addr;
423 data->io_lock = io_lock;
424
425 strlcpy(data->wdinfo.identity, "sch56xx watchdog",
426 sizeof(data->wdinfo.identity));
427 data->wdinfo.firmware_version = revision;
428 data->wdinfo.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT;
429 if (!nowayout)
430 data->wdinfo.options |= WDIOF_MAGICCLOSE;
431
432 data->wddev.info = &data->wdinfo;
433 data->wddev.ops = &watchdog_ops;
434 data->wddev.parent = parent;
435 data->wddev.timeout = 60;
436 data->wddev.min_timeout = 1;
437 data->wddev.max_timeout = 255 * 60;
438 if (nowayout)
439 set_bit(WDOG_NO_WAY_OUT, &data->wddev.status);
440 if (output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)
441 set_bit(WDOG_ACTIVE, &data->wddev.status);
442
443 /* Since the watchdog uses a downcounter there is no register to read
444 the BIOS set timeout from (if any was set at all) ->
445 Choose a preset which will give us a 1 minute timeout */
446 if (control & SCH56XX_WDOG_TIME_BASE_SEC)
447 data->watchdog_preset = 60; /* seconds */
448 else
449 data->watchdog_preset = 1; /* minute */
450
451 data->watchdog_control = control;
452 data->watchdog_output_enable = output_enable;
453
454 watchdog_set_drvdata(&data->wddev, data);
455 err = watchdog_register_device(&data->wddev);
456 if (err) {
457 pr_err("Registering watchdog chardev: %d\n", err);
458 kfree(data);
459 return NULL;
460 }
461
462 return data;
463}
464EXPORT_SYMBOL(sch56xx_watchdog_register);
465
466void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data)
467{
468 watchdog_unregister_device(&data->wddev);
469 kfree(data);
470}
471EXPORT_SYMBOL(sch56xx_watchdog_unregister);
472
473/*
474 * platform dev find, add and remove functions
475 */
476
477static int __init sch56xx_find(int sioaddr, const char **name)
478{
479 u8 devid;
480 unsigned short address;
481 int err;
482
483 err = superio_enter(sioaddr);
484 if (err)
485 return err;
486
487 devid = superio_inb(sioaddr, SIO_REG_DEVID);
488 switch (devid) {
489 case SIO_SCH5627_ID:
490 *name = "sch5627";
491 break;
492 case SIO_SCH5636_ID:
493 *name = "sch5636";
494 break;
495 default:
496 pr_debug("Unsupported device id: 0x%02x\n",
497 (unsigned int)devid);
498 err = -ENODEV;
499 goto exit;
500 }
501
502 superio_select(sioaddr, SIO_SCH56XX_LD_EM);
503
504 if (!(superio_inb(sioaddr, SIO_REG_ENABLE) & 0x01)) {
505 pr_warn("Device not activated\n");
506 err = -ENODEV;
507 goto exit;
508 }
509
510 /*
511 * Warning the order of the low / high byte is the other way around
512 * as on most other superio devices!!
513 */
514 address = superio_inb(sioaddr, SIO_REG_ADDR) |
515 superio_inb(sioaddr, SIO_REG_ADDR + 1) << 8;
516 if (address == 0) {
517 pr_warn("Base address not set\n");
518 err = -ENODEV;
519 goto exit;
520 }
521 err = address;
522
523exit:
524 superio_exit(sioaddr);
525 return err;
526}
527
528static int __init sch56xx_device_add(int address, const char *name)
529{
530 struct resource res = {
531 .start = address,
532 .end = address + REGION_LENGTH - 1,
533 .flags = IORESOURCE_IO,
534 };
535 int err;
536
537 sch56xx_pdev = platform_device_alloc(name, address);
538 if (!sch56xx_pdev)
539 return -ENOMEM;
540
541 res.name = sch56xx_pdev->name;
542 err = acpi_check_resource_conflict(&res);
543 if (err)
544 goto exit_device_put;
545
546 err = platform_device_add_resources(sch56xx_pdev, &res, 1);
547 if (err) {
548 pr_err("Device resource addition failed\n");
549 goto exit_device_put;
550 }
551
552 err = platform_device_add(sch56xx_pdev);
553 if (err) {
554 pr_err("Device addition failed\n");
555 goto exit_device_put;
556 }
557
558 return 0;
559
560exit_device_put:
561 platform_device_put(sch56xx_pdev);
562
563 return err;
564}
565
566static int __init sch56xx_init(void)
567{
568 int address;
569 const char *name = NULL;
570
571 address = sch56xx_find(0x4e, &name);
572 if (address < 0)
573 address = sch56xx_find(0x2e, &name);
574 if (address < 0)
575 return address;
576
577 return sch56xx_device_add(address, name);
578}
579
580static void __exit sch56xx_exit(void)
581{
582 platform_device_unregister(sch56xx_pdev);
583}
584
585MODULE_DESCRIPTION("SMSC SCH56xx Hardware Monitoring Common Code");
586MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
587MODULE_LICENSE("GPL");
588
589module_init(sch56xx_init);
590module_exit(sch56xx_exit);