xref: /openbmc/linux/drivers/hwmon/fschmd.c (revision f519cd13)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * fschmd.c
4  *
5  * Copyright (C) 2007 - 2009 Hans de Goede <hdegoede@redhat.com>
6  */
7 
8 /*
9  *  Merged Fujitsu Siemens hwmon driver, supporting the Poseidon, Hermes,
10  *  Scylla, Heracles, Heimdall, Hades and Syleus chips
11  *
12  *  Based on the original 2.4 fscscy, 2.6 fscpos, 2.6 fscher and 2.6
13  *  (candidate) fschmd drivers:
14  *  Copyright (C) 2006 Thilo Cestonaro
15  *			<thilo.cestonaro.external@fujitsu-siemens.com>
16  *  Copyright (C) 2004, 2005 Stefan Ott <stefan@desire.ch>
17  *  Copyright (C) 2003, 2004 Reinhard Nissl <rnissl@gmx.de>
18  *  Copyright (c) 2001 Martin Knoblauch <mkn@teraport.de, knobi@knobisoft.de>
19  *  Copyright (C) 2000 Hermann Jung <hej@odn.de>
20  */
21 
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/jiffies.h>
26 #include <linux/i2c.h>
27 #include <linux/hwmon.h>
28 #include <linux/hwmon-sysfs.h>
29 #include <linux/err.h>
30 #include <linux/mutex.h>
31 #include <linux/sysfs.h>
32 #include <linux/dmi.h>
33 #include <linux/fs.h>
34 #include <linux/watchdog.h>
35 #include <linux/miscdevice.h>
36 #include <linux/uaccess.h>
37 #include <linux/kref.h>
38 
39 /* Addresses to scan */
40 static const unsigned short normal_i2c[] = { 0x73, I2C_CLIENT_END };
41 
42 /* Insmod parameters */
43 static bool nowayout = WATCHDOG_NOWAYOUT;
44 module_param(nowayout, bool, 0);
45 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
46 	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
47 
48 enum chips { fscpos, fscher, fscscy, fschrc, fschmd, fschds, fscsyl };
49 
50 /*
51  * The FSCHMD registers and other defines
52  */
53 
54 /* chip identification */
55 #define FSCHMD_REG_IDENT_0		0x00
56 #define FSCHMD_REG_IDENT_1		0x01
57 #define FSCHMD_REG_IDENT_2		0x02
58 #define FSCHMD_REG_REVISION		0x03
59 
60 /* global control and status */
61 #define FSCHMD_REG_EVENT_STATE		0x04
62 #define FSCHMD_REG_CONTROL		0x05
63 
64 #define FSCHMD_CONTROL_ALERT_LED	0x01
65 
66 /* watchdog */
67 static const u8 FSCHMD_REG_WDOG_CONTROL[7] = {
68 	0x21, 0x21, 0x21, 0x21, 0x21, 0x28, 0x28 };
69 static const u8 FSCHMD_REG_WDOG_STATE[7] = {
70 	0x23, 0x23, 0x23, 0x23, 0x23, 0x29, 0x29 };
71 static const u8 FSCHMD_REG_WDOG_PRESET[7] = {
72 	0x28, 0x28, 0x28, 0x28, 0x28, 0x2a, 0x2a };
73 
74 #define FSCHMD_WDOG_CONTROL_TRIGGER	0x10
75 #define FSCHMD_WDOG_CONTROL_STARTED	0x10 /* the same as trigger */
76 #define FSCHMD_WDOG_CONTROL_STOP	0x20
77 #define FSCHMD_WDOG_CONTROL_RESOLUTION	0x40
78 
79 #define FSCHMD_WDOG_STATE_CARDRESET	0x02
80 
81 /* voltages, weird order is to keep the same order as the old drivers */
82 static const u8 FSCHMD_REG_VOLT[7][6] = {
83 	{ 0x45, 0x42, 0x48 },				/* pos */
84 	{ 0x45, 0x42, 0x48 },				/* her */
85 	{ 0x45, 0x42, 0x48 },				/* scy */
86 	{ 0x45, 0x42, 0x48 },				/* hrc */
87 	{ 0x45, 0x42, 0x48 },				/* hmd */
88 	{ 0x21, 0x20, 0x22 },				/* hds */
89 	{ 0x21, 0x20, 0x22, 0x23, 0x24, 0x25 },		/* syl */
90 };
91 
92 static const int FSCHMD_NO_VOLT_SENSORS[7] = { 3, 3, 3, 3, 3, 3, 6 };
93 
94 /*
95  * minimum pwm at which the fan is driven (pwm can be increased depending on
96  * the temp. Notice that for the scy some fans share there minimum speed.
97  * Also notice that with the scy the sensor order is different than with the
98  * other chips, this order was in the 2.4 driver and kept for consistency.
99  */
100 static const u8 FSCHMD_REG_FAN_MIN[7][7] = {
101 	{ 0x55, 0x65 },					/* pos */
102 	{ 0x55, 0x65, 0xb5 },				/* her */
103 	{ 0x65, 0x65, 0x55, 0xa5, 0x55, 0xa5 },		/* scy */
104 	{ 0x55, 0x65, 0xa5, 0xb5 },			/* hrc */
105 	{ 0x55, 0x65, 0xa5, 0xb5, 0xc5 },		/* hmd */
106 	{ 0x55, 0x65, 0xa5, 0xb5, 0xc5 },		/* hds */
107 	{ 0x54, 0x64, 0x74, 0x84, 0x94, 0xa4, 0xb4 },	/* syl */
108 };
109 
110 /* actual fan speed */
111 static const u8 FSCHMD_REG_FAN_ACT[7][7] = {
112 	{ 0x0e, 0x6b, 0xab },				/* pos */
113 	{ 0x0e, 0x6b, 0xbb },				/* her */
114 	{ 0x6b, 0x6c, 0x0e, 0xab, 0x5c, 0xbb },		/* scy */
115 	{ 0x0e, 0x6b, 0xab, 0xbb },			/* hrc */
116 	{ 0x5b, 0x6b, 0xab, 0xbb, 0xcb },		/* hmd */
117 	{ 0x5b, 0x6b, 0xab, 0xbb, 0xcb },		/* hds */
118 	{ 0x57, 0x67, 0x77, 0x87, 0x97, 0xa7, 0xb7 },	/* syl */
119 };
120 
121 /* fan status registers */
122 static const u8 FSCHMD_REG_FAN_STATE[7][7] = {
123 	{ 0x0d, 0x62, 0xa2 },				/* pos */
124 	{ 0x0d, 0x62, 0xb2 },				/* her */
125 	{ 0x62, 0x61, 0x0d, 0xa2, 0x52, 0xb2 },		/* scy */
126 	{ 0x0d, 0x62, 0xa2, 0xb2 },			/* hrc */
127 	{ 0x52, 0x62, 0xa2, 0xb2, 0xc2 },		/* hmd */
128 	{ 0x52, 0x62, 0xa2, 0xb2, 0xc2 },		/* hds */
129 	{ 0x50, 0x60, 0x70, 0x80, 0x90, 0xa0, 0xb0 },	/* syl */
130 };
131 
132 /* fan ripple / divider registers */
133 static const u8 FSCHMD_REG_FAN_RIPPLE[7][7] = {
134 	{ 0x0f, 0x6f, 0xaf },				/* pos */
135 	{ 0x0f, 0x6f, 0xbf },				/* her */
136 	{ 0x6f, 0x6f, 0x0f, 0xaf, 0x0f, 0xbf },		/* scy */
137 	{ 0x0f, 0x6f, 0xaf, 0xbf },			/* hrc */
138 	{ 0x5f, 0x6f, 0xaf, 0xbf, 0xcf },		/* hmd */
139 	{ 0x5f, 0x6f, 0xaf, 0xbf, 0xcf },		/* hds */
140 	{ 0x56, 0x66, 0x76, 0x86, 0x96, 0xa6, 0xb6 },	/* syl */
141 };
142 
143 static const int FSCHMD_NO_FAN_SENSORS[7] = { 3, 3, 6, 4, 5, 5, 7 };
144 
145 /* Fan status register bitmasks */
146 #define FSCHMD_FAN_ALARM	0x04 /* called fault by FSC! */
147 #define FSCHMD_FAN_NOT_PRESENT	0x08
148 #define FSCHMD_FAN_DISABLED	0x80
149 
150 
151 /* actual temperature registers */
152 static const u8 FSCHMD_REG_TEMP_ACT[7][11] = {
153 	{ 0x64, 0x32, 0x35 },				/* pos */
154 	{ 0x64, 0x32, 0x35 },				/* her */
155 	{ 0x64, 0xD0, 0x32, 0x35 },			/* scy */
156 	{ 0x64, 0x32, 0x35 },				/* hrc */
157 	{ 0x70, 0x80, 0x90, 0xd0, 0xe0 },		/* hmd */
158 	{ 0x70, 0x80, 0x90, 0xd0, 0xe0 },		/* hds */
159 	{ 0x58, 0x68, 0x78, 0x88, 0x98, 0xa8,		/* syl */
160 	  0xb8, 0xc8, 0xd8, 0xe8, 0xf8 },
161 };
162 
163 /* temperature state registers */
164 static const u8 FSCHMD_REG_TEMP_STATE[7][11] = {
165 	{ 0x71, 0x81, 0x91 },				/* pos */
166 	{ 0x71, 0x81, 0x91 },				/* her */
167 	{ 0x71, 0xd1, 0x81, 0x91 },			/* scy */
168 	{ 0x71, 0x81, 0x91 },				/* hrc */
169 	{ 0x71, 0x81, 0x91, 0xd1, 0xe1 },		/* hmd */
170 	{ 0x71, 0x81, 0x91, 0xd1, 0xe1 },		/* hds */
171 	{ 0x59, 0x69, 0x79, 0x89, 0x99, 0xa9,		/* syl */
172 	  0xb9, 0xc9, 0xd9, 0xe9, 0xf9 },
173 };
174 
175 /*
176  * temperature high limit registers, FSC does not document these. Proven to be
177  * there with field testing on the fscher and fschrc, already supported / used
178  * in the fscscy 2.4 driver. FSC has confirmed that the fschmd has registers
179  * at these addresses, but doesn't want to confirm they are the same as with
180  * the fscher??
181  */
182 static const u8 FSCHMD_REG_TEMP_LIMIT[7][11] = {
183 	{ 0, 0, 0 },					/* pos */
184 	{ 0x76, 0x86, 0x96 },				/* her */
185 	{ 0x76, 0xd6, 0x86, 0x96 },			/* scy */
186 	{ 0x76, 0x86, 0x96 },				/* hrc */
187 	{ 0x76, 0x86, 0x96, 0xd6, 0xe6 },		/* hmd */
188 	{ 0x76, 0x86, 0x96, 0xd6, 0xe6 },		/* hds */
189 	{ 0x5a, 0x6a, 0x7a, 0x8a, 0x9a, 0xaa,		/* syl */
190 	  0xba, 0xca, 0xda, 0xea, 0xfa },
191 };
192 
193 /*
194  * These were found through experimenting with an fscher, currently they are
195  * not used, but we keep them around for future reference.
196  * On the fscsyl AUTOP1 lives at 0x#c (so 0x5c for fan1, 0x6c for fan2, etc),
197  * AUTOP2 lives at 0x#e, and 0x#1 is a bitmask defining which temps influence
198  * the fan speed.
199  * static const u8 FSCHER_REG_TEMP_AUTOP1[] =	{ 0x73, 0x83, 0x93 };
200  * static const u8 FSCHER_REG_TEMP_AUTOP2[] =	{ 0x75, 0x85, 0x95 };
201  */
202 
203 static const int FSCHMD_NO_TEMP_SENSORS[7] = { 3, 3, 4, 3, 5, 5, 11 };
204 
205 /* temp status register bitmasks */
206 #define FSCHMD_TEMP_WORKING	0x01
207 #define FSCHMD_TEMP_ALERT	0x02
208 #define FSCHMD_TEMP_DISABLED	0x80
209 /* there only really is an alarm if the sensor is working and alert == 1 */
210 #define FSCHMD_TEMP_ALARM_MASK \
211 	(FSCHMD_TEMP_WORKING | FSCHMD_TEMP_ALERT)
212 
213 /*
214  * Functions declarations
215  */
216 
217 static int fschmd_probe(struct i2c_client *client,
218 			const struct i2c_device_id *id);
219 static int fschmd_detect(struct i2c_client *client,
220 			 struct i2c_board_info *info);
221 static int fschmd_remove(struct i2c_client *client);
222 static struct fschmd_data *fschmd_update_device(struct device *dev);
223 
224 /*
225  * Driver data (common to all clients)
226  */
227 
228 static const struct i2c_device_id fschmd_id[] = {
229 	{ "fscpos", fscpos },
230 	{ "fscher", fscher },
231 	{ "fscscy", fscscy },
232 	{ "fschrc", fschrc },
233 	{ "fschmd", fschmd },
234 	{ "fschds", fschds },
235 	{ "fscsyl", fscsyl },
236 	{ }
237 };
238 MODULE_DEVICE_TABLE(i2c, fschmd_id);
239 
240 static struct i2c_driver fschmd_driver = {
241 	.class		= I2C_CLASS_HWMON,
242 	.driver = {
243 		.name	= "fschmd",
244 	},
245 	.probe		= fschmd_probe,
246 	.remove		= fschmd_remove,
247 	.id_table	= fschmd_id,
248 	.detect		= fschmd_detect,
249 	.address_list	= normal_i2c,
250 };
251 
252 /*
253  * Client data (each client gets its own)
254  */
255 
256 struct fschmd_data {
257 	struct i2c_client *client;
258 	struct device *hwmon_dev;
259 	struct mutex update_lock;
260 	struct mutex watchdog_lock;
261 	struct list_head list; /* member of the watchdog_data_list */
262 	struct kref kref;
263 	struct miscdevice watchdog_miscdev;
264 	enum chips kind;
265 	unsigned long watchdog_is_open;
266 	char watchdog_expect_close;
267 	char watchdog_name[10]; /* must be unique to avoid sysfs conflict */
268 	char valid; /* zero until following fields are valid */
269 	unsigned long last_updated; /* in jiffies */
270 
271 	/* register values */
272 	u8 revision;            /* chip revision */
273 	u8 global_control;	/* global control register */
274 	u8 watchdog_control;    /* watchdog control register */
275 	u8 watchdog_state;      /* watchdog status register */
276 	u8 watchdog_preset;     /* watchdog counter preset on trigger val */
277 	u8 volt[6];		/* voltage */
278 	u8 temp_act[11];	/* temperature */
279 	u8 temp_status[11];	/* status of sensor */
280 	u8 temp_max[11];	/* high temp limit, notice: undocumented! */
281 	u8 fan_act[7];		/* fans revolutions per second */
282 	u8 fan_status[7];	/* fan status */
283 	u8 fan_min[7];		/* fan min value for rps */
284 	u8 fan_ripple[7];	/* divider for rps */
285 };
286 
287 /*
288  * Global variables to hold information read from special DMI tables, which are
289  * available on FSC machines with an fscher or later chip. There is no need to
290  * protect these with a lock as they are only modified from our attach function
291  * which always gets called with the i2c-core lock held and never accessed
292  * before the attach function is done with them.
293  */
294 static int dmi_mult[6] = { 490, 200, 100, 100, 200, 100 };
295 static int dmi_offset[6] = { 0, 0, 0, 0, 0, 0 };
296 static int dmi_vref = -1;
297 
298 /*
299  * Somewhat ugly :( global data pointer list with all fschmd devices, so that
300  * we can find our device data as when using misc_register there is no other
301  * method to get to ones device data from the open fop.
302  */
303 static LIST_HEAD(watchdog_data_list);
304 /* Note this lock not only protect list access, but also data.kref access */
305 static DEFINE_MUTEX(watchdog_data_mutex);
306 
307 /*
308  * Release our data struct when we're detached from the i2c client *and* all
309  * references to our watchdog device are released
310  */
311 static void fschmd_release_resources(struct kref *ref)
312 {
313 	struct fschmd_data *data = container_of(ref, struct fschmd_data, kref);
314 	kfree(data);
315 }
316 
317 /*
318  * Sysfs attr show / store functions
319  */
320 
321 static ssize_t in_value_show(struct device *dev,
322 			     struct device_attribute *devattr, char *buf)
323 {
324 	const int max_reading[3] = { 14200, 6600, 3300 };
325 	int index = to_sensor_dev_attr(devattr)->index;
326 	struct fschmd_data *data = fschmd_update_device(dev);
327 
328 	if (data->kind == fscher || data->kind >= fschrc)
329 		return sprintf(buf, "%d\n", (data->volt[index] * dmi_vref *
330 			dmi_mult[index]) / 255 + dmi_offset[index]);
331 	else
332 		return sprintf(buf, "%d\n", (data->volt[index] *
333 			max_reading[index] + 128) / 255);
334 }
335 
336 
337 #define TEMP_FROM_REG(val)	(((val) - 128) * 1000)
338 
339 static ssize_t temp_value_show(struct device *dev,
340 			       struct device_attribute *devattr, char *buf)
341 {
342 	int index = to_sensor_dev_attr(devattr)->index;
343 	struct fschmd_data *data = fschmd_update_device(dev);
344 
345 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_act[index]));
346 }
347 
348 static ssize_t temp_max_show(struct device *dev,
349 			     struct device_attribute *devattr, char *buf)
350 {
351 	int index = to_sensor_dev_attr(devattr)->index;
352 	struct fschmd_data *data = fschmd_update_device(dev);
353 
354 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[index]));
355 }
356 
357 static ssize_t temp_max_store(struct device *dev,
358 			      struct device_attribute *devattr,
359 			      const char *buf, size_t count)
360 {
361 	int index = to_sensor_dev_attr(devattr)->index;
362 	struct fschmd_data *data = dev_get_drvdata(dev);
363 	long v;
364 	int err;
365 
366 	err = kstrtol(buf, 10, &v);
367 	if (err)
368 		return err;
369 
370 	v = clamp_val(v / 1000, -128, 127) + 128;
371 
372 	mutex_lock(&data->update_lock);
373 	i2c_smbus_write_byte_data(to_i2c_client(dev),
374 		FSCHMD_REG_TEMP_LIMIT[data->kind][index], v);
375 	data->temp_max[index] = v;
376 	mutex_unlock(&data->update_lock);
377 
378 	return count;
379 }
380 
381 static ssize_t temp_fault_show(struct device *dev,
382 			       struct device_attribute *devattr, char *buf)
383 {
384 	int index = to_sensor_dev_attr(devattr)->index;
385 	struct fschmd_data *data = fschmd_update_device(dev);
386 
387 	/* bit 0 set means sensor working ok, so no fault! */
388 	if (data->temp_status[index] & FSCHMD_TEMP_WORKING)
389 		return sprintf(buf, "0\n");
390 	else
391 		return sprintf(buf, "1\n");
392 }
393 
394 static ssize_t temp_alarm_show(struct device *dev,
395 			       struct device_attribute *devattr, char *buf)
396 {
397 	int index = to_sensor_dev_attr(devattr)->index;
398 	struct fschmd_data *data = fschmd_update_device(dev);
399 
400 	if ((data->temp_status[index] & FSCHMD_TEMP_ALARM_MASK) ==
401 			FSCHMD_TEMP_ALARM_MASK)
402 		return sprintf(buf, "1\n");
403 	else
404 		return sprintf(buf, "0\n");
405 }
406 
407 
408 #define RPM_FROM_REG(val)	((val) * 60)
409 
410 static ssize_t fan_value_show(struct device *dev,
411 			      struct device_attribute *devattr, char *buf)
412 {
413 	int index = to_sensor_dev_attr(devattr)->index;
414 	struct fschmd_data *data = fschmd_update_device(dev);
415 
416 	return sprintf(buf, "%u\n", RPM_FROM_REG(data->fan_act[index]));
417 }
418 
419 static ssize_t fan_div_show(struct device *dev,
420 			    struct device_attribute *devattr, char *buf)
421 {
422 	int index = to_sensor_dev_attr(devattr)->index;
423 	struct fschmd_data *data = fschmd_update_device(dev);
424 
425 	/* bits 2..7 reserved => mask with 3 */
426 	return sprintf(buf, "%d\n", 1 << (data->fan_ripple[index] & 3));
427 }
428 
429 static ssize_t fan_div_store(struct device *dev,
430 			     struct device_attribute *devattr,
431 			     const char *buf, size_t count)
432 {
433 	u8 reg;
434 	int index = to_sensor_dev_attr(devattr)->index;
435 	struct fschmd_data *data = dev_get_drvdata(dev);
436 	/* supported values: 2, 4, 8 */
437 	unsigned long v;
438 	int err;
439 
440 	err = kstrtoul(buf, 10, &v);
441 	if (err)
442 		return err;
443 
444 	switch (v) {
445 	case 2:
446 		v = 1;
447 		break;
448 	case 4:
449 		v = 2;
450 		break;
451 	case 8:
452 		v = 3;
453 		break;
454 	default:
455 		dev_err(dev,
456 			"fan_div value %lu not supported. Choose one of 2, 4 or 8!\n",
457 			v);
458 		return -EINVAL;
459 	}
460 
461 	mutex_lock(&data->update_lock);
462 
463 	reg = i2c_smbus_read_byte_data(to_i2c_client(dev),
464 		FSCHMD_REG_FAN_RIPPLE[data->kind][index]);
465 
466 	/* bits 2..7 reserved => mask with 0x03 */
467 	reg &= ~0x03;
468 	reg |= v;
469 
470 	i2c_smbus_write_byte_data(to_i2c_client(dev),
471 		FSCHMD_REG_FAN_RIPPLE[data->kind][index], reg);
472 
473 	data->fan_ripple[index] = reg;
474 
475 	mutex_unlock(&data->update_lock);
476 
477 	return count;
478 }
479 
480 static ssize_t fan_alarm_show(struct device *dev,
481 			      struct device_attribute *devattr, char *buf)
482 {
483 	int index = to_sensor_dev_attr(devattr)->index;
484 	struct fschmd_data *data = fschmd_update_device(dev);
485 
486 	if (data->fan_status[index] & FSCHMD_FAN_ALARM)
487 		return sprintf(buf, "1\n");
488 	else
489 		return sprintf(buf, "0\n");
490 }
491 
492 static ssize_t fan_fault_show(struct device *dev,
493 			      struct device_attribute *devattr, char *buf)
494 {
495 	int index = to_sensor_dev_attr(devattr)->index;
496 	struct fschmd_data *data = fschmd_update_device(dev);
497 
498 	if (data->fan_status[index] & FSCHMD_FAN_NOT_PRESENT)
499 		return sprintf(buf, "1\n");
500 	else
501 		return sprintf(buf, "0\n");
502 }
503 
504 
505 static ssize_t pwm_auto_point1_pwm_show(struct device *dev,
506 					struct device_attribute *devattr,
507 					char *buf)
508 {
509 	int index = to_sensor_dev_attr(devattr)->index;
510 	struct fschmd_data *data = fschmd_update_device(dev);
511 	int val = data->fan_min[index];
512 
513 	/* 0 = allow turning off (except on the syl), 1-255 = 50-100% */
514 	if (val || data->kind == fscsyl)
515 		val = val / 2 + 128;
516 
517 	return sprintf(buf, "%d\n", val);
518 }
519 
520 static ssize_t pwm_auto_point1_pwm_store(struct device *dev,
521 					 struct device_attribute *devattr,
522 					 const char *buf, size_t count)
523 {
524 	int index = to_sensor_dev_attr(devattr)->index;
525 	struct fschmd_data *data = dev_get_drvdata(dev);
526 	unsigned long v;
527 	int err;
528 
529 	err = kstrtoul(buf, 10, &v);
530 	if (err)
531 		return err;
532 
533 	/* reg: 0 = allow turning off (except on the syl), 1-255 = 50-100% */
534 	if (v || data->kind == fscsyl) {
535 		v = clamp_val(v, 128, 255);
536 		v = (v - 128) * 2 + 1;
537 	}
538 
539 	mutex_lock(&data->update_lock);
540 
541 	i2c_smbus_write_byte_data(to_i2c_client(dev),
542 		FSCHMD_REG_FAN_MIN[data->kind][index], v);
543 	data->fan_min[index] = v;
544 
545 	mutex_unlock(&data->update_lock);
546 
547 	return count;
548 }
549 
550 
551 /*
552  * The FSC hwmon family has the ability to force an attached alert led to flash
553  * from software, we export this as an alert_led sysfs attr
554  */
555 static ssize_t alert_led_show(struct device *dev,
556 	struct device_attribute *devattr, char *buf)
557 {
558 	struct fschmd_data *data = fschmd_update_device(dev);
559 
560 	if (data->global_control & FSCHMD_CONTROL_ALERT_LED)
561 		return sprintf(buf, "1\n");
562 	else
563 		return sprintf(buf, "0\n");
564 }
565 
566 static ssize_t alert_led_store(struct device *dev,
567 	struct device_attribute *devattr, const char *buf, size_t count)
568 {
569 	u8 reg;
570 	struct fschmd_data *data = dev_get_drvdata(dev);
571 	unsigned long v;
572 	int err;
573 
574 	err = kstrtoul(buf, 10, &v);
575 	if (err)
576 		return err;
577 
578 	mutex_lock(&data->update_lock);
579 
580 	reg = i2c_smbus_read_byte_data(to_i2c_client(dev), FSCHMD_REG_CONTROL);
581 
582 	if (v)
583 		reg |= FSCHMD_CONTROL_ALERT_LED;
584 	else
585 		reg &= ~FSCHMD_CONTROL_ALERT_LED;
586 
587 	i2c_smbus_write_byte_data(to_i2c_client(dev), FSCHMD_REG_CONTROL, reg);
588 
589 	data->global_control = reg;
590 
591 	mutex_unlock(&data->update_lock);
592 
593 	return count;
594 }
595 
596 static DEVICE_ATTR_RW(alert_led);
597 
598 static struct sensor_device_attribute fschmd_attr[] = {
599 	SENSOR_ATTR_RO(in0_input, in_value, 0),
600 	SENSOR_ATTR_RO(in1_input, in_value, 1),
601 	SENSOR_ATTR_RO(in2_input, in_value, 2),
602 	SENSOR_ATTR_RO(in3_input, in_value, 3),
603 	SENSOR_ATTR_RO(in4_input, in_value, 4),
604 	SENSOR_ATTR_RO(in5_input, in_value, 5),
605 };
606 
607 static struct sensor_device_attribute fschmd_temp_attr[] = {
608 	SENSOR_ATTR_RO(temp1_input, temp_value, 0),
609 	SENSOR_ATTR_RW(temp1_max, temp_max, 0),
610 	SENSOR_ATTR_RO(temp1_fault, temp_fault, 0),
611 	SENSOR_ATTR_RO(temp1_alarm, temp_alarm, 0),
612 	SENSOR_ATTR_RO(temp2_input, temp_value, 1),
613 	SENSOR_ATTR_RW(temp2_max, temp_max, 1),
614 	SENSOR_ATTR_RO(temp2_fault, temp_fault, 1),
615 	SENSOR_ATTR_RO(temp2_alarm, temp_alarm, 1),
616 	SENSOR_ATTR_RO(temp3_input, temp_value, 2),
617 	SENSOR_ATTR_RW(temp3_max, temp_max, 2),
618 	SENSOR_ATTR_RO(temp3_fault, temp_fault, 2),
619 	SENSOR_ATTR_RO(temp3_alarm, temp_alarm, 2),
620 	SENSOR_ATTR_RO(temp4_input, temp_value, 3),
621 	SENSOR_ATTR_RW(temp4_max, temp_max, 3),
622 	SENSOR_ATTR_RO(temp4_fault, temp_fault, 3),
623 	SENSOR_ATTR_RO(temp4_alarm, temp_alarm, 3),
624 	SENSOR_ATTR_RO(temp5_input, temp_value, 4),
625 	SENSOR_ATTR_RW(temp5_max, temp_max, 4),
626 	SENSOR_ATTR_RO(temp5_fault, temp_fault, 4),
627 	SENSOR_ATTR_RO(temp5_alarm, temp_alarm, 4),
628 	SENSOR_ATTR_RO(temp6_input, temp_value, 5),
629 	SENSOR_ATTR_RW(temp6_max, temp_max, 5),
630 	SENSOR_ATTR_RO(temp6_fault, temp_fault, 5),
631 	SENSOR_ATTR_RO(temp6_alarm, temp_alarm, 5),
632 	SENSOR_ATTR_RO(temp7_input, temp_value, 6),
633 	SENSOR_ATTR_RW(temp7_max, temp_max, 6),
634 	SENSOR_ATTR_RO(temp7_fault, temp_fault, 6),
635 	SENSOR_ATTR_RO(temp7_alarm, temp_alarm, 6),
636 	SENSOR_ATTR_RO(temp8_input, temp_value, 7),
637 	SENSOR_ATTR_RW(temp8_max, temp_max, 7),
638 	SENSOR_ATTR_RO(temp8_fault, temp_fault, 7),
639 	SENSOR_ATTR_RO(temp8_alarm, temp_alarm, 7),
640 	SENSOR_ATTR_RO(temp9_input, temp_value, 8),
641 	SENSOR_ATTR_RW(temp9_max, temp_max, 8),
642 	SENSOR_ATTR_RO(temp9_fault, temp_fault, 8),
643 	SENSOR_ATTR_RO(temp9_alarm, temp_alarm, 8),
644 	SENSOR_ATTR_RO(temp10_input, temp_value, 9),
645 	SENSOR_ATTR_RW(temp10_max, temp_max, 9),
646 	SENSOR_ATTR_RO(temp10_fault, temp_fault, 9),
647 	SENSOR_ATTR_RO(temp10_alarm, temp_alarm, 9),
648 	SENSOR_ATTR_RO(temp11_input, temp_value, 10),
649 	SENSOR_ATTR_RW(temp11_max, temp_max, 10),
650 	SENSOR_ATTR_RO(temp11_fault, temp_fault, 10),
651 	SENSOR_ATTR_RO(temp11_alarm, temp_alarm, 10),
652 };
653 
654 static struct sensor_device_attribute fschmd_fan_attr[] = {
655 	SENSOR_ATTR_RO(fan1_input, fan_value, 0),
656 	SENSOR_ATTR_RW(fan1_div, fan_div, 0),
657 	SENSOR_ATTR_RO(fan1_alarm, fan_alarm, 0),
658 	SENSOR_ATTR_RO(fan1_fault, fan_fault, 0),
659 	SENSOR_ATTR_RW(pwm1_auto_point1_pwm, pwm_auto_point1_pwm, 0),
660 	SENSOR_ATTR_RO(fan2_input, fan_value, 1),
661 	SENSOR_ATTR_RW(fan2_div, fan_div, 1),
662 	SENSOR_ATTR_RO(fan2_alarm, fan_alarm, 1),
663 	SENSOR_ATTR_RO(fan2_fault, fan_fault, 1),
664 	SENSOR_ATTR_RW(pwm2_auto_point1_pwm, pwm_auto_point1_pwm, 1),
665 	SENSOR_ATTR_RO(fan3_input, fan_value, 2),
666 	SENSOR_ATTR_RW(fan3_div, fan_div, 2),
667 	SENSOR_ATTR_RO(fan3_alarm, fan_alarm, 2),
668 	SENSOR_ATTR_RO(fan3_fault, fan_fault, 2),
669 	SENSOR_ATTR_RW(pwm3_auto_point1_pwm, pwm_auto_point1_pwm, 2),
670 	SENSOR_ATTR_RO(fan4_input, fan_value, 3),
671 	SENSOR_ATTR_RW(fan4_div, fan_div, 3),
672 	SENSOR_ATTR_RO(fan4_alarm, fan_alarm, 3),
673 	SENSOR_ATTR_RO(fan4_fault, fan_fault, 3),
674 	SENSOR_ATTR_RW(pwm4_auto_point1_pwm, pwm_auto_point1_pwm, 3),
675 	SENSOR_ATTR_RO(fan5_input, fan_value, 4),
676 	SENSOR_ATTR_RW(fan5_div, fan_div, 4),
677 	SENSOR_ATTR_RO(fan5_alarm, fan_alarm, 4),
678 	SENSOR_ATTR_RO(fan5_fault, fan_fault, 4),
679 	SENSOR_ATTR_RW(pwm5_auto_point1_pwm, pwm_auto_point1_pwm, 4),
680 	SENSOR_ATTR_RO(fan6_input, fan_value, 5),
681 	SENSOR_ATTR_RW(fan6_div, fan_div, 5),
682 	SENSOR_ATTR_RO(fan6_alarm, fan_alarm, 5),
683 	SENSOR_ATTR_RO(fan6_fault, fan_fault, 5),
684 	SENSOR_ATTR_RW(pwm6_auto_point1_pwm, pwm_auto_point1_pwm, 5),
685 	SENSOR_ATTR_RO(fan7_input, fan_value, 6),
686 	SENSOR_ATTR_RW(fan7_div, fan_div, 6),
687 	SENSOR_ATTR_RO(fan7_alarm, fan_alarm, 6),
688 	SENSOR_ATTR_RO(fan7_fault, fan_fault, 6),
689 	SENSOR_ATTR_RW(pwm7_auto_point1_pwm, pwm_auto_point1_pwm, 6),
690 };
691 
692 
693 /*
694  * Watchdog routines
695  */
696 
697 static int watchdog_set_timeout(struct fschmd_data *data, int timeout)
698 {
699 	int ret, resolution;
700 	int kind = data->kind + 1; /* 0-x array index -> 1-x module param */
701 
702 	/* 2 second or 60 second resolution? */
703 	if (timeout <= 510 || kind == fscpos || kind == fscscy)
704 		resolution = 2;
705 	else
706 		resolution = 60;
707 
708 	if (timeout < resolution || timeout > (resolution * 255))
709 		return -EINVAL;
710 
711 	mutex_lock(&data->watchdog_lock);
712 	if (!data->client) {
713 		ret = -ENODEV;
714 		goto leave;
715 	}
716 
717 	if (resolution == 2)
718 		data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_RESOLUTION;
719 	else
720 		data->watchdog_control |= FSCHMD_WDOG_CONTROL_RESOLUTION;
721 
722 	data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
723 
724 	/* Write new timeout value */
725 	i2c_smbus_write_byte_data(data->client,
726 		FSCHMD_REG_WDOG_PRESET[data->kind], data->watchdog_preset);
727 	/* Write new control register, do not trigger! */
728 	i2c_smbus_write_byte_data(data->client,
729 		FSCHMD_REG_WDOG_CONTROL[data->kind],
730 		data->watchdog_control & ~FSCHMD_WDOG_CONTROL_TRIGGER);
731 
732 	ret = data->watchdog_preset * resolution;
733 
734 leave:
735 	mutex_unlock(&data->watchdog_lock);
736 	return ret;
737 }
738 
739 static int watchdog_get_timeout(struct fschmd_data *data)
740 {
741 	int timeout;
742 
743 	mutex_lock(&data->watchdog_lock);
744 	if (data->watchdog_control & FSCHMD_WDOG_CONTROL_RESOLUTION)
745 		timeout = data->watchdog_preset * 60;
746 	else
747 		timeout = data->watchdog_preset * 2;
748 	mutex_unlock(&data->watchdog_lock);
749 
750 	return timeout;
751 }
752 
753 static int watchdog_trigger(struct fschmd_data *data)
754 {
755 	int ret = 0;
756 
757 	mutex_lock(&data->watchdog_lock);
758 	if (!data->client) {
759 		ret = -ENODEV;
760 		goto leave;
761 	}
762 
763 	data->watchdog_control |= FSCHMD_WDOG_CONTROL_TRIGGER;
764 	i2c_smbus_write_byte_data(data->client,
765 				  FSCHMD_REG_WDOG_CONTROL[data->kind],
766 				  data->watchdog_control);
767 leave:
768 	mutex_unlock(&data->watchdog_lock);
769 	return ret;
770 }
771 
772 static int watchdog_stop(struct fschmd_data *data)
773 {
774 	int ret = 0;
775 
776 	mutex_lock(&data->watchdog_lock);
777 	if (!data->client) {
778 		ret = -ENODEV;
779 		goto leave;
780 	}
781 
782 	data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_STARTED;
783 	/*
784 	 * Don't store the stop flag in our watchdog control register copy, as
785 	 * its a write only bit (read always returns 0)
786 	 */
787 	i2c_smbus_write_byte_data(data->client,
788 		FSCHMD_REG_WDOG_CONTROL[data->kind],
789 		data->watchdog_control | FSCHMD_WDOG_CONTROL_STOP);
790 leave:
791 	mutex_unlock(&data->watchdog_lock);
792 	return ret;
793 }
794 
795 static int watchdog_open(struct inode *inode, struct file *filp)
796 {
797 	struct fschmd_data *pos, *data = NULL;
798 	int watchdog_is_open;
799 
800 	/*
801 	 * We get called from drivers/char/misc.c with misc_mtx hold, and we
802 	 * call misc_register() from fschmd_probe() with watchdog_data_mutex
803 	 * hold, as misc_register() takes the misc_mtx lock, this is a possible
804 	 * deadlock, so we use mutex_trylock here.
805 	 */
806 	if (!mutex_trylock(&watchdog_data_mutex))
807 		return -ERESTARTSYS;
808 	list_for_each_entry(pos, &watchdog_data_list, list) {
809 		if (pos->watchdog_miscdev.minor == iminor(inode)) {
810 			data = pos;
811 			break;
812 		}
813 	}
814 	/* Note we can never not have found data, so we don't check for this */
815 	watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open);
816 	if (!watchdog_is_open)
817 		kref_get(&data->kref);
818 	mutex_unlock(&watchdog_data_mutex);
819 
820 	if (watchdog_is_open)
821 		return -EBUSY;
822 
823 	/* Start the watchdog */
824 	watchdog_trigger(data);
825 	filp->private_data = data;
826 
827 	return stream_open(inode, filp);
828 }
829 
830 static int watchdog_release(struct inode *inode, struct file *filp)
831 {
832 	struct fschmd_data *data = filp->private_data;
833 
834 	if (data->watchdog_expect_close) {
835 		watchdog_stop(data);
836 		data->watchdog_expect_close = 0;
837 	} else {
838 		watchdog_trigger(data);
839 		dev_crit(&data->client->dev,
840 			"unexpected close, not stopping watchdog!\n");
841 	}
842 
843 	clear_bit(0, &data->watchdog_is_open);
844 
845 	mutex_lock(&watchdog_data_mutex);
846 	kref_put(&data->kref, fschmd_release_resources);
847 	mutex_unlock(&watchdog_data_mutex);
848 
849 	return 0;
850 }
851 
852 static ssize_t watchdog_write(struct file *filp, const char __user *buf,
853 	size_t count, loff_t *offset)
854 {
855 	int ret;
856 	struct fschmd_data *data = filp->private_data;
857 
858 	if (count) {
859 		if (!nowayout) {
860 			size_t i;
861 
862 			/* Clear it in case it was set with a previous write */
863 			data->watchdog_expect_close = 0;
864 
865 			for (i = 0; i != count; i++) {
866 				char c;
867 				if (get_user(c, buf + i))
868 					return -EFAULT;
869 				if (c == 'V')
870 					data->watchdog_expect_close = 1;
871 			}
872 		}
873 		ret = watchdog_trigger(data);
874 		if (ret < 0)
875 			return ret;
876 	}
877 	return count;
878 }
879 
880 static long watchdog_ioctl(struct file *filp, unsigned int cmd,
881 			   unsigned long arg)
882 {
883 	struct watchdog_info ident = {
884 		.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
885 				WDIOF_CARDRESET,
886 		.identity = "FSC watchdog"
887 	};
888 	int i, ret = 0;
889 	struct fschmd_data *data = filp->private_data;
890 
891 	switch (cmd) {
892 	case WDIOC_GETSUPPORT:
893 		ident.firmware_version = data->revision;
894 		if (!nowayout)
895 			ident.options |= WDIOF_MAGICCLOSE;
896 		if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
897 			ret = -EFAULT;
898 		break;
899 
900 	case WDIOC_GETSTATUS:
901 		ret = put_user(0, (int __user *)arg);
902 		break;
903 
904 	case WDIOC_GETBOOTSTATUS:
905 		if (data->watchdog_state & FSCHMD_WDOG_STATE_CARDRESET)
906 			ret = put_user(WDIOF_CARDRESET, (int __user *)arg);
907 		else
908 			ret = put_user(0, (int __user *)arg);
909 		break;
910 
911 	case WDIOC_KEEPALIVE:
912 		ret = watchdog_trigger(data);
913 		break;
914 
915 	case WDIOC_GETTIMEOUT:
916 		i = watchdog_get_timeout(data);
917 		ret = put_user(i, (int __user *)arg);
918 		break;
919 
920 	case WDIOC_SETTIMEOUT:
921 		if (get_user(i, (int __user *)arg)) {
922 			ret = -EFAULT;
923 			break;
924 		}
925 		ret = watchdog_set_timeout(data, i);
926 		if (ret > 0)
927 			ret = put_user(ret, (int __user *)arg);
928 		break;
929 
930 	case WDIOC_SETOPTIONS:
931 		if (get_user(i, (int __user *)arg)) {
932 			ret = -EFAULT;
933 			break;
934 		}
935 
936 		if (i & WDIOS_DISABLECARD)
937 			ret = watchdog_stop(data);
938 		else if (i & WDIOS_ENABLECARD)
939 			ret = watchdog_trigger(data);
940 		else
941 			ret = -EINVAL;
942 
943 		break;
944 	default:
945 		ret = -ENOTTY;
946 	}
947 	return ret;
948 }
949 
950 static const struct file_operations watchdog_fops = {
951 	.owner = THIS_MODULE,
952 	.llseek = no_llseek,
953 	.open = watchdog_open,
954 	.release = watchdog_release,
955 	.write = watchdog_write,
956 	.unlocked_ioctl = watchdog_ioctl,
957 	.compat_ioctl = compat_ptr_ioctl,
958 };
959 
960 
961 /*
962  * Detect, register, unregister and update device functions
963  */
964 
965 /*
966  * DMI decode routine to read voltage scaling factors from special DMI tables,
967  * which are available on FSC machines with an fscher or later chip.
968  */
969 static void fschmd_dmi_decode(const struct dmi_header *header, void *dummy)
970 {
971 	int i, mult[3] = { 0 }, offset[3] = { 0 }, vref = 0, found = 0;
972 
973 	/*
974 	 * dmi code ugliness, we get passed the address of the contents of
975 	 * a complete DMI record, but in the form of a dmi_header pointer, in
976 	 * reality this address holds header->length bytes of which the header
977 	 * are the first 4 bytes
978 	 */
979 	u8 *dmi_data = (u8 *)header;
980 
981 	/* We are looking for OEM-specific type 185 */
982 	if (header->type != 185)
983 		return;
984 
985 	/*
986 	 * we are looking for what Siemens calls "subtype" 19, the subtype
987 	 * is stored in byte 5 of the dmi block
988 	 */
989 	if (header->length < 5 || dmi_data[4] != 19)
990 		return;
991 
992 	/*
993 	 * After the subtype comes 1 unknown byte and then blocks of 5 bytes,
994 	 * consisting of what Siemens calls an "Entity" number, followed by
995 	 * 2 16-bit words in LSB first order
996 	 */
997 	for (i = 6; (i + 4) < header->length; i += 5) {
998 		/* entity 1 - 3: voltage multiplier and offset */
999 		if (dmi_data[i] >= 1 && dmi_data[i] <= 3) {
1000 			/* Our in sensors order and the DMI order differ */
1001 			const int shuffle[3] = { 1, 0, 2 };
1002 			int in = shuffle[dmi_data[i] - 1];
1003 
1004 			/* Check for twice the same entity */
1005 			if (found & (1 << in))
1006 				return;
1007 
1008 			mult[in] = dmi_data[i + 1] | (dmi_data[i + 2] << 8);
1009 			offset[in] = dmi_data[i + 3] | (dmi_data[i + 4] << 8);
1010 
1011 			found |= 1 << in;
1012 		}
1013 
1014 		/* entity 7: reference voltage */
1015 		if (dmi_data[i] == 7) {
1016 			/* Check for twice the same entity */
1017 			if (found & 0x08)
1018 				return;
1019 
1020 			vref = dmi_data[i + 1] | (dmi_data[i + 2] << 8);
1021 
1022 			found |= 0x08;
1023 		}
1024 	}
1025 
1026 	if (found == 0x0F) {
1027 		for (i = 0; i < 3; i++) {
1028 			dmi_mult[i] = mult[i] * 10;
1029 			dmi_offset[i] = offset[i] * 10;
1030 		}
1031 		/*
1032 		 * According to the docs there should be separate dmi entries
1033 		 * for the mult's and offsets of in3-5 of the syl, but on
1034 		 * my test machine these are not present
1035 		 */
1036 		dmi_mult[3] = dmi_mult[2];
1037 		dmi_mult[4] = dmi_mult[1];
1038 		dmi_mult[5] = dmi_mult[2];
1039 		dmi_offset[3] = dmi_offset[2];
1040 		dmi_offset[4] = dmi_offset[1];
1041 		dmi_offset[5] = dmi_offset[2];
1042 		dmi_vref = vref;
1043 	}
1044 }
1045 
1046 static int fschmd_detect(struct i2c_client *client,
1047 			 struct i2c_board_info *info)
1048 {
1049 	enum chips kind;
1050 	struct i2c_adapter *adapter = client->adapter;
1051 	char id[4];
1052 
1053 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
1054 		return -ENODEV;
1055 
1056 	/* Detect & Identify the chip */
1057 	id[0] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_0);
1058 	id[1] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_1);
1059 	id[2] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_2);
1060 	id[3] = '\0';
1061 
1062 	if (!strcmp(id, "PEG"))
1063 		kind = fscpos;
1064 	else if (!strcmp(id, "HER"))
1065 		kind = fscher;
1066 	else if (!strcmp(id, "SCY"))
1067 		kind = fscscy;
1068 	else if (!strcmp(id, "HRC"))
1069 		kind = fschrc;
1070 	else if (!strcmp(id, "HMD"))
1071 		kind = fschmd;
1072 	else if (!strcmp(id, "HDS"))
1073 		kind = fschds;
1074 	else if (!strcmp(id, "SYL"))
1075 		kind = fscsyl;
1076 	else
1077 		return -ENODEV;
1078 
1079 	strlcpy(info->type, fschmd_id[kind].name, I2C_NAME_SIZE);
1080 
1081 	return 0;
1082 }
1083 
1084 static int fschmd_probe(struct i2c_client *client,
1085 			const struct i2c_device_id *id)
1086 {
1087 	struct fschmd_data *data;
1088 	const char * const names[7] = { "Poseidon", "Hermes", "Scylla",
1089 				"Heracles", "Heimdall", "Hades", "Syleus" };
1090 	const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 };
1091 	int i, err;
1092 	enum chips kind = id->driver_data;
1093 
1094 	data = kzalloc(sizeof(struct fschmd_data), GFP_KERNEL);
1095 	if (!data)
1096 		return -ENOMEM;
1097 
1098 	i2c_set_clientdata(client, data);
1099 	mutex_init(&data->update_lock);
1100 	mutex_init(&data->watchdog_lock);
1101 	INIT_LIST_HEAD(&data->list);
1102 	kref_init(&data->kref);
1103 	/*
1104 	 * Store client pointer in our data struct for watchdog usage
1105 	 * (where the client is found through a data ptr instead of the
1106 	 * otherway around)
1107 	 */
1108 	data->client = client;
1109 	data->kind = kind;
1110 
1111 	if (kind == fscpos) {
1112 		/*
1113 		 * The Poseidon has hardwired temp limits, fill these
1114 		 * in for the alarm resetting code
1115 		 */
1116 		data->temp_max[0] = 70 + 128;
1117 		data->temp_max[1] = 50 + 128;
1118 		data->temp_max[2] = 50 + 128;
1119 	}
1120 
1121 	/* Read the special DMI table for fscher and newer chips */
1122 	if ((kind == fscher || kind >= fschrc) && dmi_vref == -1) {
1123 		dmi_walk(fschmd_dmi_decode, NULL);
1124 		if (dmi_vref == -1) {
1125 			dev_warn(&client->dev,
1126 				"Couldn't get voltage scaling factors from "
1127 				"BIOS DMI table, using builtin defaults\n");
1128 			dmi_vref = 33;
1129 		}
1130 	}
1131 
1132 	/* Read in some never changing registers */
1133 	data->revision = i2c_smbus_read_byte_data(client, FSCHMD_REG_REVISION);
1134 	data->global_control = i2c_smbus_read_byte_data(client,
1135 					FSCHMD_REG_CONTROL);
1136 	data->watchdog_control = i2c_smbus_read_byte_data(client,
1137 					FSCHMD_REG_WDOG_CONTROL[data->kind]);
1138 	data->watchdog_state = i2c_smbus_read_byte_data(client,
1139 					FSCHMD_REG_WDOG_STATE[data->kind]);
1140 	data->watchdog_preset = i2c_smbus_read_byte_data(client,
1141 					FSCHMD_REG_WDOG_PRESET[data->kind]);
1142 
1143 	err = device_create_file(&client->dev, &dev_attr_alert_led);
1144 	if (err)
1145 		goto exit_detach;
1146 
1147 	for (i = 0; i < FSCHMD_NO_VOLT_SENSORS[data->kind]; i++) {
1148 		err = device_create_file(&client->dev,
1149 					&fschmd_attr[i].dev_attr);
1150 		if (err)
1151 			goto exit_detach;
1152 	}
1153 
1154 	for (i = 0; i < (FSCHMD_NO_TEMP_SENSORS[data->kind] * 4); i++) {
1155 		/* Poseidon doesn't have TEMP_LIMIT registers */
1156 		if (kind == fscpos && fschmd_temp_attr[i].dev_attr.show ==
1157 				temp_max_show)
1158 			continue;
1159 
1160 		if (kind == fscsyl) {
1161 			if (i % 4 == 0)
1162 				data->temp_status[i / 4] =
1163 					i2c_smbus_read_byte_data(client,
1164 						FSCHMD_REG_TEMP_STATE
1165 						[data->kind][i / 4]);
1166 			if (data->temp_status[i / 4] & FSCHMD_TEMP_DISABLED)
1167 				continue;
1168 		}
1169 
1170 		err = device_create_file(&client->dev,
1171 					&fschmd_temp_attr[i].dev_attr);
1172 		if (err)
1173 			goto exit_detach;
1174 	}
1175 
1176 	for (i = 0; i < (FSCHMD_NO_FAN_SENSORS[data->kind] * 5); i++) {
1177 		/* Poseidon doesn't have a FAN_MIN register for its 3rd fan */
1178 		if (kind == fscpos &&
1179 				!strcmp(fschmd_fan_attr[i].dev_attr.attr.name,
1180 					"pwm3_auto_point1_pwm"))
1181 			continue;
1182 
1183 		if (kind == fscsyl) {
1184 			if (i % 5 == 0)
1185 				data->fan_status[i / 5] =
1186 					i2c_smbus_read_byte_data(client,
1187 						FSCHMD_REG_FAN_STATE
1188 						[data->kind][i / 5]);
1189 			if (data->fan_status[i / 5] & FSCHMD_FAN_DISABLED)
1190 				continue;
1191 		}
1192 
1193 		err = device_create_file(&client->dev,
1194 					&fschmd_fan_attr[i].dev_attr);
1195 		if (err)
1196 			goto exit_detach;
1197 	}
1198 
1199 	data->hwmon_dev = hwmon_device_register(&client->dev);
1200 	if (IS_ERR(data->hwmon_dev)) {
1201 		err = PTR_ERR(data->hwmon_dev);
1202 		data->hwmon_dev = NULL;
1203 		goto exit_detach;
1204 	}
1205 
1206 	/*
1207 	 * We take the data_mutex lock early so that watchdog_open() cannot
1208 	 * run when misc_register() has completed, but we've not yet added
1209 	 * our data to the watchdog_data_list (and set the default timeout)
1210 	 */
1211 	mutex_lock(&watchdog_data_mutex);
1212 	for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) {
1213 		/* Register our watchdog part */
1214 		snprintf(data->watchdog_name, sizeof(data->watchdog_name),
1215 			"watchdog%c", (i == 0) ? '\0' : ('0' + i));
1216 		data->watchdog_miscdev.name = data->watchdog_name;
1217 		data->watchdog_miscdev.fops = &watchdog_fops;
1218 		data->watchdog_miscdev.minor = watchdog_minors[i];
1219 		err = misc_register(&data->watchdog_miscdev);
1220 		if (err == -EBUSY)
1221 			continue;
1222 		if (err) {
1223 			data->watchdog_miscdev.minor = 0;
1224 			dev_err(&client->dev,
1225 				"Registering watchdog chardev: %d\n", err);
1226 			break;
1227 		}
1228 
1229 		list_add(&data->list, &watchdog_data_list);
1230 		watchdog_set_timeout(data, 60);
1231 		dev_info(&client->dev,
1232 			"Registered watchdog chardev major 10, minor: %d\n",
1233 			watchdog_minors[i]);
1234 		break;
1235 	}
1236 	if (i == ARRAY_SIZE(watchdog_minors)) {
1237 		data->watchdog_miscdev.minor = 0;
1238 		dev_warn(&client->dev,
1239 			 "Couldn't register watchdog chardev (due to no free minor)\n");
1240 	}
1241 	mutex_unlock(&watchdog_data_mutex);
1242 
1243 	dev_info(&client->dev, "Detected FSC %s chip, revision: %d\n",
1244 		names[data->kind], (int) data->revision);
1245 
1246 	return 0;
1247 
1248 exit_detach:
1249 	fschmd_remove(client); /* will also free data for us */
1250 	return err;
1251 }
1252 
1253 static int fschmd_remove(struct i2c_client *client)
1254 {
1255 	struct fschmd_data *data = i2c_get_clientdata(client);
1256 	int i;
1257 
1258 	/* Unregister the watchdog (if registered) */
1259 	if (data->watchdog_miscdev.minor) {
1260 		misc_deregister(&data->watchdog_miscdev);
1261 		if (data->watchdog_is_open) {
1262 			dev_warn(&client->dev,
1263 				"i2c client detached with watchdog open! "
1264 				"Stopping watchdog.\n");
1265 			watchdog_stop(data);
1266 		}
1267 		mutex_lock(&watchdog_data_mutex);
1268 		list_del(&data->list);
1269 		mutex_unlock(&watchdog_data_mutex);
1270 		/* Tell the watchdog code the client is gone */
1271 		mutex_lock(&data->watchdog_lock);
1272 		data->client = NULL;
1273 		mutex_unlock(&data->watchdog_lock);
1274 	}
1275 
1276 	/*
1277 	 * Check if registered in case we're called from fschmd_detect
1278 	 * to cleanup after an error
1279 	 */
1280 	if (data->hwmon_dev)
1281 		hwmon_device_unregister(data->hwmon_dev);
1282 
1283 	device_remove_file(&client->dev, &dev_attr_alert_led);
1284 	for (i = 0; i < (FSCHMD_NO_VOLT_SENSORS[data->kind]); i++)
1285 		device_remove_file(&client->dev, &fschmd_attr[i].dev_attr);
1286 	for (i = 0; i < (FSCHMD_NO_TEMP_SENSORS[data->kind] * 4); i++)
1287 		device_remove_file(&client->dev,
1288 					&fschmd_temp_attr[i].dev_attr);
1289 	for (i = 0; i < (FSCHMD_NO_FAN_SENSORS[data->kind] * 5); i++)
1290 		device_remove_file(&client->dev,
1291 					&fschmd_fan_attr[i].dev_attr);
1292 
1293 	mutex_lock(&watchdog_data_mutex);
1294 	kref_put(&data->kref, fschmd_release_resources);
1295 	mutex_unlock(&watchdog_data_mutex);
1296 
1297 	return 0;
1298 }
1299 
1300 static struct fschmd_data *fschmd_update_device(struct device *dev)
1301 {
1302 	struct i2c_client *client = to_i2c_client(dev);
1303 	struct fschmd_data *data = i2c_get_clientdata(client);
1304 	int i;
1305 
1306 	mutex_lock(&data->update_lock);
1307 
1308 	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
1309 
1310 		for (i = 0; i < FSCHMD_NO_TEMP_SENSORS[data->kind]; i++) {
1311 			data->temp_act[i] = i2c_smbus_read_byte_data(client,
1312 					FSCHMD_REG_TEMP_ACT[data->kind][i]);
1313 			data->temp_status[i] = i2c_smbus_read_byte_data(client,
1314 					FSCHMD_REG_TEMP_STATE[data->kind][i]);
1315 
1316 			/* The fscpos doesn't have TEMP_LIMIT registers */
1317 			if (FSCHMD_REG_TEMP_LIMIT[data->kind][i])
1318 				data->temp_max[i] = i2c_smbus_read_byte_data(
1319 					client,
1320 					FSCHMD_REG_TEMP_LIMIT[data->kind][i]);
1321 
1322 			/*
1323 			 * reset alarm if the alarm condition is gone,
1324 			 * the chip doesn't do this itself
1325 			 */
1326 			if ((data->temp_status[i] & FSCHMD_TEMP_ALARM_MASK) ==
1327 					FSCHMD_TEMP_ALARM_MASK &&
1328 					data->temp_act[i] < data->temp_max[i])
1329 				i2c_smbus_write_byte_data(client,
1330 					FSCHMD_REG_TEMP_STATE[data->kind][i],
1331 					data->temp_status[i]);
1332 		}
1333 
1334 		for (i = 0; i < FSCHMD_NO_FAN_SENSORS[data->kind]; i++) {
1335 			data->fan_act[i] = i2c_smbus_read_byte_data(client,
1336 					FSCHMD_REG_FAN_ACT[data->kind][i]);
1337 			data->fan_status[i] = i2c_smbus_read_byte_data(client,
1338 					FSCHMD_REG_FAN_STATE[data->kind][i]);
1339 			data->fan_ripple[i] = i2c_smbus_read_byte_data(client,
1340 					FSCHMD_REG_FAN_RIPPLE[data->kind][i]);
1341 
1342 			/* The fscpos third fan doesn't have a fan_min */
1343 			if (FSCHMD_REG_FAN_MIN[data->kind][i])
1344 				data->fan_min[i] = i2c_smbus_read_byte_data(
1345 					client,
1346 					FSCHMD_REG_FAN_MIN[data->kind][i]);
1347 
1348 			/* reset fan status if speed is back to > 0 */
1349 			if ((data->fan_status[i] & FSCHMD_FAN_ALARM) &&
1350 					data->fan_act[i])
1351 				i2c_smbus_write_byte_data(client,
1352 					FSCHMD_REG_FAN_STATE[data->kind][i],
1353 					data->fan_status[i]);
1354 		}
1355 
1356 		for (i = 0; i < FSCHMD_NO_VOLT_SENSORS[data->kind]; i++)
1357 			data->volt[i] = i2c_smbus_read_byte_data(client,
1358 					       FSCHMD_REG_VOLT[data->kind][i]);
1359 
1360 		data->last_updated = jiffies;
1361 		data->valid = 1;
1362 	}
1363 
1364 	mutex_unlock(&data->update_lock);
1365 
1366 	return data;
1367 }
1368 
1369 module_i2c_driver(fschmd_driver);
1370 
1371 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
1372 MODULE_DESCRIPTION("FSC Poseidon, Hermes, Scylla, Heracles, Heimdall, Hades "
1373 			"and Syleus driver");
1374 MODULE_LICENSE("GPL");
1375