xref: /linux/drivers/hwmon/fschmd.c (revision 97733180fafbeb7cc3fd1c8be60d05980615f5d6)
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 static int fschmd_detect(struct i2c_client *client,
219 			 struct i2c_board_info *info);
220 static int fschmd_remove(struct i2c_client *client);
221 static struct fschmd_data *fschmd_update_device(struct device *dev);
222 
223 /*
224  * Driver data (common to all clients)
225  */
226 
227 static const struct i2c_device_id fschmd_id[] = {
228 	{ "fscpos", fscpos },
229 	{ "fscher", fscher },
230 	{ "fscscy", fscscy },
231 	{ "fschrc", fschrc },
232 	{ "fschmd", fschmd },
233 	{ "fschds", fschds },
234 	{ "fscsyl", fscsyl },
235 	{ }
236 };
237 MODULE_DEVICE_TABLE(i2c, fschmd_id);
238 
239 static struct i2c_driver fschmd_driver = {
240 	.class		= I2C_CLASS_HWMON,
241 	.driver = {
242 		.name	= "fschmd",
243 	},
244 	.probe_new	= fschmd_probe,
245 	.remove		= fschmd_remove,
246 	.id_table	= fschmd_id,
247 	.detect		= fschmd_detect,
248 	.address_list	= normal_i2c,
249 };
250 
251 /*
252  * Client data (each client gets its own)
253  */
254 
255 struct fschmd_data {
256 	struct i2c_client *client;
257 	struct device *hwmon_dev;
258 	struct mutex update_lock;
259 	struct mutex watchdog_lock;
260 	struct list_head list; /* member of the watchdog_data_list */
261 	struct kref kref;
262 	struct miscdevice watchdog_miscdev;
263 	enum chips kind;
264 	unsigned long watchdog_is_open;
265 	char watchdog_expect_close;
266 	char watchdog_name[10]; /* must be unique to avoid sysfs conflict */
267 	bool valid; /* false until following fields are valid */
268 	unsigned long last_updated; /* in jiffies */
269 
270 	/* register values */
271 	u8 revision;            /* chip revision */
272 	u8 global_control;	/* global control register */
273 	u8 watchdog_control;    /* watchdog control register */
274 	u8 watchdog_state;      /* watchdog status register */
275 	u8 watchdog_preset;     /* watchdog counter preset on trigger val */
276 	u8 volt[6];		/* voltage */
277 	u8 temp_act[11];	/* temperature */
278 	u8 temp_status[11];	/* status of sensor */
279 	u8 temp_max[11];	/* high temp limit, notice: undocumented! */
280 	u8 fan_act[7];		/* fans revolutions per second */
281 	u8 fan_status[7];	/* fan status */
282 	u8 fan_min[7];		/* fan min value for rps */
283 	u8 fan_ripple[7];	/* divider for rps */
284 };
285 
286 /*
287  * Global variables to hold information read from special DMI tables, which are
288  * available on FSC machines with an fscher or later chip. There is no need to
289  * protect these with a lock as they are only modified from our attach function
290  * which always gets called with the i2c-core lock held and never accessed
291  * before the attach function is done with them.
292  */
293 static int dmi_mult[6] = { 490, 200, 100, 100, 200, 100 };
294 static int dmi_offset[6] = { 0, 0, 0, 0, 0, 0 };
295 static int dmi_vref = -1;
296 
297 /*
298  * Somewhat ugly :( global data pointer list with all fschmd devices, so that
299  * we can find our device data as when using misc_register there is no other
300  * method to get to ones device data from the open fop.
301  */
302 static LIST_HEAD(watchdog_data_list);
303 /* Note this lock not only protect list access, but also data.kref access */
304 static DEFINE_MUTEX(watchdog_data_mutex);
305 
306 /*
307  * Release our data struct when we're detached from the i2c client *and* all
308  * references to our watchdog device are released
309  */
310 static void fschmd_release_resources(struct kref *ref)
311 {
312 	struct fschmd_data *data = container_of(ref, struct fschmd_data, kref);
313 	kfree(data);
314 }
315 
316 /*
317  * Sysfs attr show / store functions
318  */
319 
320 static ssize_t in_value_show(struct device *dev,
321 			     struct device_attribute *devattr, char *buf)
322 {
323 	const int max_reading[3] = { 14200, 6600, 3300 };
324 	int index = to_sensor_dev_attr(devattr)->index;
325 	struct fschmd_data *data = fschmd_update_device(dev);
326 
327 	if (data->kind == fscher || data->kind >= fschrc)
328 		return sprintf(buf, "%d\n", (data->volt[index] * dmi_vref *
329 			dmi_mult[index]) / 255 + dmi_offset[index]);
330 	else
331 		return sprintf(buf, "%d\n", (data->volt[index] *
332 			max_reading[index] + 128) / 255);
333 }
334 
335 
336 #define TEMP_FROM_REG(val)	(((val) - 128) * 1000)
337 
338 static ssize_t temp_value_show(struct device *dev,
339 			       struct device_attribute *devattr, char *buf)
340 {
341 	int index = to_sensor_dev_attr(devattr)->index;
342 	struct fschmd_data *data = fschmd_update_device(dev);
343 
344 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_act[index]));
345 }
346 
347 static ssize_t temp_max_show(struct device *dev,
348 			     struct device_attribute *devattr, char *buf)
349 {
350 	int index = to_sensor_dev_attr(devattr)->index;
351 	struct fschmd_data *data = fschmd_update_device(dev);
352 
353 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[index]));
354 }
355 
356 static ssize_t temp_max_store(struct device *dev,
357 			      struct device_attribute *devattr,
358 			      const char *buf, size_t count)
359 {
360 	int index = to_sensor_dev_attr(devattr)->index;
361 	struct fschmd_data *data = dev_get_drvdata(dev);
362 	long v;
363 	int err;
364 
365 	err = kstrtol(buf, 10, &v);
366 	if (err)
367 		return err;
368 
369 	v = clamp_val(v / 1000, -128, 127) + 128;
370 
371 	mutex_lock(&data->update_lock);
372 	i2c_smbus_write_byte_data(to_i2c_client(dev),
373 		FSCHMD_REG_TEMP_LIMIT[data->kind][index], v);
374 	data->temp_max[index] = v;
375 	mutex_unlock(&data->update_lock);
376 
377 	return count;
378 }
379 
380 static ssize_t temp_fault_show(struct device *dev,
381 			       struct device_attribute *devattr, char *buf)
382 {
383 	int index = to_sensor_dev_attr(devattr)->index;
384 	struct fschmd_data *data = fschmd_update_device(dev);
385 
386 	/* bit 0 set means sensor working ok, so no fault! */
387 	if (data->temp_status[index] & FSCHMD_TEMP_WORKING)
388 		return sprintf(buf, "0\n");
389 	else
390 		return sprintf(buf, "1\n");
391 }
392 
393 static ssize_t temp_alarm_show(struct device *dev,
394 			       struct device_attribute *devattr, char *buf)
395 {
396 	int index = to_sensor_dev_attr(devattr)->index;
397 	struct fschmd_data *data = fschmd_update_device(dev);
398 
399 	if ((data->temp_status[index] & FSCHMD_TEMP_ALARM_MASK) ==
400 			FSCHMD_TEMP_ALARM_MASK)
401 		return sprintf(buf, "1\n");
402 	else
403 		return sprintf(buf, "0\n");
404 }
405 
406 
407 #define RPM_FROM_REG(val)	((val) * 60)
408 
409 static ssize_t fan_value_show(struct device *dev,
410 			      struct device_attribute *devattr, char *buf)
411 {
412 	int index = to_sensor_dev_attr(devattr)->index;
413 	struct fschmd_data *data = fschmd_update_device(dev);
414 
415 	return sprintf(buf, "%u\n", RPM_FROM_REG(data->fan_act[index]));
416 }
417 
418 static ssize_t fan_div_show(struct device *dev,
419 			    struct device_attribute *devattr, char *buf)
420 {
421 	int index = to_sensor_dev_attr(devattr)->index;
422 	struct fschmd_data *data = fschmd_update_device(dev);
423 
424 	/* bits 2..7 reserved => mask with 3 */
425 	return sprintf(buf, "%d\n", 1 << (data->fan_ripple[index] & 3));
426 }
427 
428 static ssize_t fan_div_store(struct device *dev,
429 			     struct device_attribute *devattr,
430 			     const char *buf, size_t count)
431 {
432 	u8 reg;
433 	int index = to_sensor_dev_attr(devattr)->index;
434 	struct fschmd_data *data = dev_get_drvdata(dev);
435 	/* supported values: 2, 4, 8 */
436 	unsigned long v;
437 	int err;
438 
439 	err = kstrtoul(buf, 10, &v);
440 	if (err)
441 		return err;
442 
443 	switch (v) {
444 	case 2:
445 		v = 1;
446 		break;
447 	case 4:
448 		v = 2;
449 		break;
450 	case 8:
451 		v = 3;
452 		break;
453 	default:
454 		dev_err(dev,
455 			"fan_div value %lu not supported. Choose one of 2, 4 or 8!\n",
456 			v);
457 		return -EINVAL;
458 	}
459 
460 	mutex_lock(&data->update_lock);
461 
462 	reg = i2c_smbus_read_byte_data(to_i2c_client(dev),
463 		FSCHMD_REG_FAN_RIPPLE[data->kind][index]);
464 
465 	/* bits 2..7 reserved => mask with 0x03 */
466 	reg &= ~0x03;
467 	reg |= v;
468 
469 	i2c_smbus_write_byte_data(to_i2c_client(dev),
470 		FSCHMD_REG_FAN_RIPPLE[data->kind][index], reg);
471 
472 	data->fan_ripple[index] = reg;
473 
474 	mutex_unlock(&data->update_lock);
475 
476 	return count;
477 }
478 
479 static ssize_t fan_alarm_show(struct device *dev,
480 			      struct device_attribute *devattr, char *buf)
481 {
482 	int index = to_sensor_dev_attr(devattr)->index;
483 	struct fschmd_data *data = fschmd_update_device(dev);
484 
485 	if (data->fan_status[index] & FSCHMD_FAN_ALARM)
486 		return sprintf(buf, "1\n");
487 	else
488 		return sprintf(buf, "0\n");
489 }
490 
491 static ssize_t fan_fault_show(struct device *dev,
492 			      struct device_attribute *devattr, char *buf)
493 {
494 	int index = to_sensor_dev_attr(devattr)->index;
495 	struct fschmd_data *data = fschmd_update_device(dev);
496 
497 	if (data->fan_status[index] & FSCHMD_FAN_NOT_PRESENT)
498 		return sprintf(buf, "1\n");
499 	else
500 		return sprintf(buf, "0\n");
501 }
502 
503 
504 static ssize_t pwm_auto_point1_pwm_show(struct device *dev,
505 					struct device_attribute *devattr,
506 					char *buf)
507 {
508 	int index = to_sensor_dev_attr(devattr)->index;
509 	struct fschmd_data *data = fschmd_update_device(dev);
510 	int val = data->fan_min[index];
511 
512 	/* 0 = allow turning off (except on the syl), 1-255 = 50-100% */
513 	if (val || data->kind == fscsyl)
514 		val = val / 2 + 128;
515 
516 	return sprintf(buf, "%d\n", val);
517 }
518 
519 static ssize_t pwm_auto_point1_pwm_store(struct device *dev,
520 					 struct device_attribute *devattr,
521 					 const char *buf, size_t count)
522 {
523 	int index = to_sensor_dev_attr(devattr)->index;
524 	struct fschmd_data *data = dev_get_drvdata(dev);
525 	unsigned long v;
526 	int err;
527 
528 	err = kstrtoul(buf, 10, &v);
529 	if (err)
530 		return err;
531 
532 	/* reg: 0 = allow turning off (except on the syl), 1-255 = 50-100% */
533 	if (v || data->kind == fscsyl) {
534 		v = clamp_val(v, 128, 255);
535 		v = (v - 128) * 2 + 1;
536 	}
537 
538 	mutex_lock(&data->update_lock);
539 
540 	i2c_smbus_write_byte_data(to_i2c_client(dev),
541 		FSCHMD_REG_FAN_MIN[data->kind][index], v);
542 	data->fan_min[index] = v;
543 
544 	mutex_unlock(&data->update_lock);
545 
546 	return count;
547 }
548 
549 
550 /*
551  * The FSC hwmon family has the ability to force an attached alert led to flash
552  * from software, we export this as an alert_led sysfs attr
553  */
554 static ssize_t alert_led_show(struct device *dev,
555 	struct device_attribute *devattr, char *buf)
556 {
557 	struct fschmd_data *data = fschmd_update_device(dev);
558 
559 	if (data->global_control & FSCHMD_CONTROL_ALERT_LED)
560 		return sprintf(buf, "1\n");
561 	else
562 		return sprintf(buf, "0\n");
563 }
564 
565 static ssize_t alert_led_store(struct device *dev,
566 	struct device_attribute *devattr, const char *buf, size_t count)
567 {
568 	u8 reg;
569 	struct fschmd_data *data = dev_get_drvdata(dev);
570 	unsigned long v;
571 	int err;
572 
573 	err = kstrtoul(buf, 10, &v);
574 	if (err)
575 		return err;
576 
577 	mutex_lock(&data->update_lock);
578 
579 	reg = i2c_smbus_read_byte_data(to_i2c_client(dev), FSCHMD_REG_CONTROL);
580 
581 	if (v)
582 		reg |= FSCHMD_CONTROL_ALERT_LED;
583 	else
584 		reg &= ~FSCHMD_CONTROL_ALERT_LED;
585 
586 	i2c_smbus_write_byte_data(to_i2c_client(dev), FSCHMD_REG_CONTROL, reg);
587 
588 	data->global_control = reg;
589 
590 	mutex_unlock(&data->update_lock);
591 
592 	return count;
593 }
594 
595 static DEVICE_ATTR_RW(alert_led);
596 
597 static struct sensor_device_attribute fschmd_attr[] = {
598 	SENSOR_ATTR_RO(in0_input, in_value, 0),
599 	SENSOR_ATTR_RO(in1_input, in_value, 1),
600 	SENSOR_ATTR_RO(in2_input, in_value, 2),
601 	SENSOR_ATTR_RO(in3_input, in_value, 3),
602 	SENSOR_ATTR_RO(in4_input, in_value, 4),
603 	SENSOR_ATTR_RO(in5_input, in_value, 5),
604 };
605 
606 static struct sensor_device_attribute fschmd_temp_attr[] = {
607 	SENSOR_ATTR_RO(temp1_input, temp_value, 0),
608 	SENSOR_ATTR_RW(temp1_max, temp_max, 0),
609 	SENSOR_ATTR_RO(temp1_fault, temp_fault, 0),
610 	SENSOR_ATTR_RO(temp1_alarm, temp_alarm, 0),
611 	SENSOR_ATTR_RO(temp2_input, temp_value, 1),
612 	SENSOR_ATTR_RW(temp2_max, temp_max, 1),
613 	SENSOR_ATTR_RO(temp2_fault, temp_fault, 1),
614 	SENSOR_ATTR_RO(temp2_alarm, temp_alarm, 1),
615 	SENSOR_ATTR_RO(temp3_input, temp_value, 2),
616 	SENSOR_ATTR_RW(temp3_max, temp_max, 2),
617 	SENSOR_ATTR_RO(temp3_fault, temp_fault, 2),
618 	SENSOR_ATTR_RO(temp3_alarm, temp_alarm, 2),
619 	SENSOR_ATTR_RO(temp4_input, temp_value, 3),
620 	SENSOR_ATTR_RW(temp4_max, temp_max, 3),
621 	SENSOR_ATTR_RO(temp4_fault, temp_fault, 3),
622 	SENSOR_ATTR_RO(temp4_alarm, temp_alarm, 3),
623 	SENSOR_ATTR_RO(temp5_input, temp_value, 4),
624 	SENSOR_ATTR_RW(temp5_max, temp_max, 4),
625 	SENSOR_ATTR_RO(temp5_fault, temp_fault, 4),
626 	SENSOR_ATTR_RO(temp5_alarm, temp_alarm, 4),
627 	SENSOR_ATTR_RO(temp6_input, temp_value, 5),
628 	SENSOR_ATTR_RW(temp6_max, temp_max, 5),
629 	SENSOR_ATTR_RO(temp6_fault, temp_fault, 5),
630 	SENSOR_ATTR_RO(temp6_alarm, temp_alarm, 5),
631 	SENSOR_ATTR_RO(temp7_input, temp_value, 6),
632 	SENSOR_ATTR_RW(temp7_max, temp_max, 6),
633 	SENSOR_ATTR_RO(temp7_fault, temp_fault, 6),
634 	SENSOR_ATTR_RO(temp7_alarm, temp_alarm, 6),
635 	SENSOR_ATTR_RO(temp8_input, temp_value, 7),
636 	SENSOR_ATTR_RW(temp8_max, temp_max, 7),
637 	SENSOR_ATTR_RO(temp8_fault, temp_fault, 7),
638 	SENSOR_ATTR_RO(temp8_alarm, temp_alarm, 7),
639 	SENSOR_ATTR_RO(temp9_input, temp_value, 8),
640 	SENSOR_ATTR_RW(temp9_max, temp_max, 8),
641 	SENSOR_ATTR_RO(temp9_fault, temp_fault, 8),
642 	SENSOR_ATTR_RO(temp9_alarm, temp_alarm, 8),
643 	SENSOR_ATTR_RO(temp10_input, temp_value, 9),
644 	SENSOR_ATTR_RW(temp10_max, temp_max, 9),
645 	SENSOR_ATTR_RO(temp10_fault, temp_fault, 9),
646 	SENSOR_ATTR_RO(temp10_alarm, temp_alarm, 9),
647 	SENSOR_ATTR_RO(temp11_input, temp_value, 10),
648 	SENSOR_ATTR_RW(temp11_max, temp_max, 10),
649 	SENSOR_ATTR_RO(temp11_fault, temp_fault, 10),
650 	SENSOR_ATTR_RO(temp11_alarm, temp_alarm, 10),
651 };
652 
653 static struct sensor_device_attribute fschmd_fan_attr[] = {
654 	SENSOR_ATTR_RO(fan1_input, fan_value, 0),
655 	SENSOR_ATTR_RW(fan1_div, fan_div, 0),
656 	SENSOR_ATTR_RO(fan1_alarm, fan_alarm, 0),
657 	SENSOR_ATTR_RO(fan1_fault, fan_fault, 0),
658 	SENSOR_ATTR_RW(pwm1_auto_point1_pwm, pwm_auto_point1_pwm, 0),
659 	SENSOR_ATTR_RO(fan2_input, fan_value, 1),
660 	SENSOR_ATTR_RW(fan2_div, fan_div, 1),
661 	SENSOR_ATTR_RO(fan2_alarm, fan_alarm, 1),
662 	SENSOR_ATTR_RO(fan2_fault, fan_fault, 1),
663 	SENSOR_ATTR_RW(pwm2_auto_point1_pwm, pwm_auto_point1_pwm, 1),
664 	SENSOR_ATTR_RO(fan3_input, fan_value, 2),
665 	SENSOR_ATTR_RW(fan3_div, fan_div, 2),
666 	SENSOR_ATTR_RO(fan3_alarm, fan_alarm, 2),
667 	SENSOR_ATTR_RO(fan3_fault, fan_fault, 2),
668 	SENSOR_ATTR_RW(pwm3_auto_point1_pwm, pwm_auto_point1_pwm, 2),
669 	SENSOR_ATTR_RO(fan4_input, fan_value, 3),
670 	SENSOR_ATTR_RW(fan4_div, fan_div, 3),
671 	SENSOR_ATTR_RO(fan4_alarm, fan_alarm, 3),
672 	SENSOR_ATTR_RO(fan4_fault, fan_fault, 3),
673 	SENSOR_ATTR_RW(pwm4_auto_point1_pwm, pwm_auto_point1_pwm, 3),
674 	SENSOR_ATTR_RO(fan5_input, fan_value, 4),
675 	SENSOR_ATTR_RW(fan5_div, fan_div, 4),
676 	SENSOR_ATTR_RO(fan5_alarm, fan_alarm, 4),
677 	SENSOR_ATTR_RO(fan5_fault, fan_fault, 4),
678 	SENSOR_ATTR_RW(pwm5_auto_point1_pwm, pwm_auto_point1_pwm, 4),
679 	SENSOR_ATTR_RO(fan6_input, fan_value, 5),
680 	SENSOR_ATTR_RW(fan6_div, fan_div, 5),
681 	SENSOR_ATTR_RO(fan6_alarm, fan_alarm, 5),
682 	SENSOR_ATTR_RO(fan6_fault, fan_fault, 5),
683 	SENSOR_ATTR_RW(pwm6_auto_point1_pwm, pwm_auto_point1_pwm, 5),
684 	SENSOR_ATTR_RO(fan7_input, fan_value, 6),
685 	SENSOR_ATTR_RW(fan7_div, fan_div, 6),
686 	SENSOR_ATTR_RO(fan7_alarm, fan_alarm, 6),
687 	SENSOR_ATTR_RO(fan7_fault, fan_fault, 6),
688 	SENSOR_ATTR_RW(pwm7_auto_point1_pwm, pwm_auto_point1_pwm, 6),
689 };
690 
691 
692 /*
693  * Watchdog routines
694  */
695 
696 static int watchdog_set_timeout(struct fschmd_data *data, int timeout)
697 {
698 	int ret, resolution;
699 	int kind = data->kind + 1; /* 0-x array index -> 1-x module param */
700 
701 	/* 2 second or 60 second resolution? */
702 	if (timeout <= 510 || kind == fscpos || kind == fscscy)
703 		resolution = 2;
704 	else
705 		resolution = 60;
706 
707 	if (timeout < resolution || timeout > (resolution * 255))
708 		return -EINVAL;
709 
710 	mutex_lock(&data->watchdog_lock);
711 	if (!data->client) {
712 		ret = -ENODEV;
713 		goto leave;
714 	}
715 
716 	if (resolution == 2)
717 		data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_RESOLUTION;
718 	else
719 		data->watchdog_control |= FSCHMD_WDOG_CONTROL_RESOLUTION;
720 
721 	data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
722 
723 	/* Write new timeout value */
724 	i2c_smbus_write_byte_data(data->client,
725 		FSCHMD_REG_WDOG_PRESET[data->kind], data->watchdog_preset);
726 	/* Write new control register, do not trigger! */
727 	i2c_smbus_write_byte_data(data->client,
728 		FSCHMD_REG_WDOG_CONTROL[data->kind],
729 		data->watchdog_control & ~FSCHMD_WDOG_CONTROL_TRIGGER);
730 
731 	ret = data->watchdog_preset * resolution;
732 
733 leave:
734 	mutex_unlock(&data->watchdog_lock);
735 	return ret;
736 }
737 
738 static int watchdog_get_timeout(struct fschmd_data *data)
739 {
740 	int timeout;
741 
742 	mutex_lock(&data->watchdog_lock);
743 	if (data->watchdog_control & FSCHMD_WDOG_CONTROL_RESOLUTION)
744 		timeout = data->watchdog_preset * 60;
745 	else
746 		timeout = data->watchdog_preset * 2;
747 	mutex_unlock(&data->watchdog_lock);
748 
749 	return timeout;
750 }
751 
752 static int watchdog_trigger(struct fschmd_data *data)
753 {
754 	int ret = 0;
755 
756 	mutex_lock(&data->watchdog_lock);
757 	if (!data->client) {
758 		ret = -ENODEV;
759 		goto leave;
760 	}
761 
762 	data->watchdog_control |= FSCHMD_WDOG_CONTROL_TRIGGER;
763 	i2c_smbus_write_byte_data(data->client,
764 				  FSCHMD_REG_WDOG_CONTROL[data->kind],
765 				  data->watchdog_control);
766 leave:
767 	mutex_unlock(&data->watchdog_lock);
768 	return ret;
769 }
770 
771 static int watchdog_stop(struct fschmd_data *data)
772 {
773 	int ret = 0;
774 
775 	mutex_lock(&data->watchdog_lock);
776 	if (!data->client) {
777 		ret = -ENODEV;
778 		goto leave;
779 	}
780 
781 	data->watchdog_control &= ~FSCHMD_WDOG_CONTROL_STARTED;
782 	/*
783 	 * Don't store the stop flag in our watchdog control register copy, as
784 	 * its a write only bit (read always returns 0)
785 	 */
786 	i2c_smbus_write_byte_data(data->client,
787 		FSCHMD_REG_WDOG_CONTROL[data->kind],
788 		data->watchdog_control | FSCHMD_WDOG_CONTROL_STOP);
789 leave:
790 	mutex_unlock(&data->watchdog_lock);
791 	return ret;
792 }
793 
794 static int watchdog_open(struct inode *inode, struct file *filp)
795 {
796 	struct fschmd_data *pos, *data = NULL;
797 	int watchdog_is_open;
798 
799 	/*
800 	 * We get called from drivers/char/misc.c with misc_mtx hold, and we
801 	 * call misc_register() from fschmd_probe() with watchdog_data_mutex
802 	 * hold, as misc_register() takes the misc_mtx lock, this is a possible
803 	 * deadlock, so we use mutex_trylock here.
804 	 */
805 	if (!mutex_trylock(&watchdog_data_mutex))
806 		return -ERESTARTSYS;
807 	list_for_each_entry(pos, &watchdog_data_list, list) {
808 		if (pos->watchdog_miscdev.minor == iminor(inode)) {
809 			data = pos;
810 			break;
811 		}
812 	}
813 	/* Note we can never not have found data, so we don't check for this */
814 	watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open);
815 	if (!watchdog_is_open)
816 		kref_get(&data->kref);
817 	mutex_unlock(&watchdog_data_mutex);
818 
819 	if (watchdog_is_open)
820 		return -EBUSY;
821 
822 	/* Start the watchdog */
823 	watchdog_trigger(data);
824 	filp->private_data = data;
825 
826 	return stream_open(inode, filp);
827 }
828 
829 static int watchdog_release(struct inode *inode, struct file *filp)
830 {
831 	struct fschmd_data *data = filp->private_data;
832 
833 	if (data->watchdog_expect_close) {
834 		watchdog_stop(data);
835 		data->watchdog_expect_close = 0;
836 	} else {
837 		watchdog_trigger(data);
838 		dev_crit(&data->client->dev,
839 			"unexpected close, not stopping watchdog!\n");
840 	}
841 
842 	clear_bit(0, &data->watchdog_is_open);
843 
844 	mutex_lock(&watchdog_data_mutex);
845 	kref_put(&data->kref, fschmd_release_resources);
846 	mutex_unlock(&watchdog_data_mutex);
847 
848 	return 0;
849 }
850 
851 static ssize_t watchdog_write(struct file *filp, const char __user *buf,
852 	size_t count, loff_t *offset)
853 {
854 	int ret;
855 	struct fschmd_data *data = filp->private_data;
856 
857 	if (count) {
858 		if (!nowayout) {
859 			size_t i;
860 
861 			/* Clear it in case it was set with a previous write */
862 			data->watchdog_expect_close = 0;
863 
864 			for (i = 0; i != count; i++) {
865 				char c;
866 				if (get_user(c, buf + i))
867 					return -EFAULT;
868 				if (c == 'V')
869 					data->watchdog_expect_close = 1;
870 			}
871 		}
872 		ret = watchdog_trigger(data);
873 		if (ret < 0)
874 			return ret;
875 	}
876 	return count;
877 }
878 
879 static long watchdog_ioctl(struct file *filp, unsigned int cmd,
880 			   unsigned long arg)
881 {
882 	struct watchdog_info ident = {
883 		.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
884 				WDIOF_CARDRESET,
885 		.identity = "FSC watchdog"
886 	};
887 	int i, ret = 0;
888 	struct fschmd_data *data = filp->private_data;
889 
890 	switch (cmd) {
891 	case WDIOC_GETSUPPORT:
892 		ident.firmware_version = data->revision;
893 		if (!nowayout)
894 			ident.options |= WDIOF_MAGICCLOSE;
895 		if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
896 			ret = -EFAULT;
897 		break;
898 
899 	case WDIOC_GETSTATUS:
900 		ret = put_user(0, (int __user *)arg);
901 		break;
902 
903 	case WDIOC_GETBOOTSTATUS:
904 		if (data->watchdog_state & FSCHMD_WDOG_STATE_CARDRESET)
905 			ret = put_user(WDIOF_CARDRESET, (int __user *)arg);
906 		else
907 			ret = put_user(0, (int __user *)arg);
908 		break;
909 
910 	case WDIOC_KEEPALIVE:
911 		ret = watchdog_trigger(data);
912 		break;
913 
914 	case WDIOC_GETTIMEOUT:
915 		i = watchdog_get_timeout(data);
916 		ret = put_user(i, (int __user *)arg);
917 		break;
918 
919 	case WDIOC_SETTIMEOUT:
920 		if (get_user(i, (int __user *)arg)) {
921 			ret = -EFAULT;
922 			break;
923 		}
924 		ret = watchdog_set_timeout(data, i);
925 		if (ret > 0)
926 			ret = put_user(ret, (int __user *)arg);
927 		break;
928 
929 	case WDIOC_SETOPTIONS:
930 		if (get_user(i, (int __user *)arg)) {
931 			ret = -EFAULT;
932 			break;
933 		}
934 
935 		if (i & WDIOS_DISABLECARD)
936 			ret = watchdog_stop(data);
937 		else if (i & WDIOS_ENABLECARD)
938 			ret = watchdog_trigger(data);
939 		else
940 			ret = -EINVAL;
941 
942 		break;
943 	default:
944 		ret = -ENOTTY;
945 	}
946 	return ret;
947 }
948 
949 static const struct file_operations watchdog_fops = {
950 	.owner = THIS_MODULE,
951 	.llseek = no_llseek,
952 	.open = watchdog_open,
953 	.release = watchdog_release,
954 	.write = watchdog_write,
955 	.unlocked_ioctl = watchdog_ioctl,
956 	.compat_ioctl = compat_ptr_ioctl,
957 };
958 
959 
960 /*
961  * Detect, register, unregister and update device functions
962  */
963 
964 /*
965  * DMI decode routine to read voltage scaling factors from special DMI tables,
966  * which are available on FSC machines with an fscher or later chip.
967  */
968 static void fschmd_dmi_decode(const struct dmi_header *header, void *dummy)
969 {
970 	int i, mult[3] = { 0 }, offset[3] = { 0 }, vref = 0, found = 0;
971 
972 	/*
973 	 * dmi code ugliness, we get passed the address of the contents of
974 	 * a complete DMI record, but in the form of a dmi_header pointer, in
975 	 * reality this address holds header->length bytes of which the header
976 	 * are the first 4 bytes
977 	 */
978 	u8 *dmi_data = (u8 *)header;
979 
980 	/* We are looking for OEM-specific type 185 */
981 	if (header->type != 185)
982 		return;
983 
984 	/*
985 	 * we are looking for what Siemens calls "subtype" 19, the subtype
986 	 * is stored in byte 5 of the dmi block
987 	 */
988 	if (header->length < 5 || dmi_data[4] != 19)
989 		return;
990 
991 	/*
992 	 * After the subtype comes 1 unknown byte and then blocks of 5 bytes,
993 	 * consisting of what Siemens calls an "Entity" number, followed by
994 	 * 2 16-bit words in LSB first order
995 	 */
996 	for (i = 6; (i + 4) < header->length; i += 5) {
997 		/* entity 1 - 3: voltage multiplier and offset */
998 		if (dmi_data[i] >= 1 && dmi_data[i] <= 3) {
999 			/* Our in sensors order and the DMI order differ */
1000 			const int shuffle[3] = { 1, 0, 2 };
1001 			int in = shuffle[dmi_data[i] - 1];
1002 
1003 			/* Check for twice the same entity */
1004 			if (found & (1 << in))
1005 				return;
1006 
1007 			mult[in] = dmi_data[i + 1] | (dmi_data[i + 2] << 8);
1008 			offset[in] = dmi_data[i + 3] | (dmi_data[i + 4] << 8);
1009 
1010 			found |= 1 << in;
1011 		}
1012 
1013 		/* entity 7: reference voltage */
1014 		if (dmi_data[i] == 7) {
1015 			/* Check for twice the same entity */
1016 			if (found & 0x08)
1017 				return;
1018 
1019 			vref = dmi_data[i + 1] | (dmi_data[i + 2] << 8);
1020 
1021 			found |= 0x08;
1022 		}
1023 	}
1024 
1025 	if (found == 0x0F) {
1026 		for (i = 0; i < 3; i++) {
1027 			dmi_mult[i] = mult[i] * 10;
1028 			dmi_offset[i] = offset[i] * 10;
1029 		}
1030 		/*
1031 		 * According to the docs there should be separate dmi entries
1032 		 * for the mult's and offsets of in3-5 of the syl, but on
1033 		 * my test machine these are not present
1034 		 */
1035 		dmi_mult[3] = dmi_mult[2];
1036 		dmi_mult[4] = dmi_mult[1];
1037 		dmi_mult[5] = dmi_mult[2];
1038 		dmi_offset[3] = dmi_offset[2];
1039 		dmi_offset[4] = dmi_offset[1];
1040 		dmi_offset[5] = dmi_offset[2];
1041 		dmi_vref = vref;
1042 	}
1043 }
1044 
1045 static int fschmd_detect(struct i2c_client *client,
1046 			 struct i2c_board_info *info)
1047 {
1048 	enum chips kind;
1049 	struct i2c_adapter *adapter = client->adapter;
1050 	char id[4];
1051 
1052 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
1053 		return -ENODEV;
1054 
1055 	/* Detect & Identify the chip */
1056 	id[0] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_0);
1057 	id[1] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_1);
1058 	id[2] = i2c_smbus_read_byte_data(client, FSCHMD_REG_IDENT_2);
1059 	id[3] = '\0';
1060 
1061 	if (!strcmp(id, "PEG"))
1062 		kind = fscpos;
1063 	else if (!strcmp(id, "HER"))
1064 		kind = fscher;
1065 	else if (!strcmp(id, "SCY"))
1066 		kind = fscscy;
1067 	else if (!strcmp(id, "HRC"))
1068 		kind = fschrc;
1069 	else if (!strcmp(id, "HMD"))
1070 		kind = fschmd;
1071 	else if (!strcmp(id, "HDS"))
1072 		kind = fschds;
1073 	else if (!strcmp(id, "SYL"))
1074 		kind = fscsyl;
1075 	else
1076 		return -ENODEV;
1077 
1078 	strlcpy(info->type, fschmd_id[kind].name, I2C_NAME_SIZE);
1079 
1080 	return 0;
1081 }
1082 
1083 static int fschmd_probe(struct i2c_client *client)
1084 {
1085 	struct fschmd_data *data;
1086 	const char * const names[7] = { "Poseidon", "Hermes", "Scylla",
1087 				"Heracles", "Heimdall", "Hades", "Syleus" };
1088 	const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 };
1089 	int i, err;
1090 	enum chips kind = i2c_match_id(fschmd_id, client)->driver_data;
1091 
1092 	data = kzalloc(sizeof(struct fschmd_data), GFP_KERNEL);
1093 	if (!data)
1094 		return -ENOMEM;
1095 
1096 	i2c_set_clientdata(client, data);
1097 	mutex_init(&data->update_lock);
1098 	mutex_init(&data->watchdog_lock);
1099 	INIT_LIST_HEAD(&data->list);
1100 	kref_init(&data->kref);
1101 	/*
1102 	 * Store client pointer in our data struct for watchdog usage
1103 	 * (where the client is found through a data ptr instead of the
1104 	 * otherway around)
1105 	 */
1106 	data->client = client;
1107 	data->kind = kind;
1108 
1109 	if (kind == fscpos) {
1110 		/*
1111 		 * The Poseidon has hardwired temp limits, fill these
1112 		 * in for the alarm resetting code
1113 		 */
1114 		data->temp_max[0] = 70 + 128;
1115 		data->temp_max[1] = 50 + 128;
1116 		data->temp_max[2] = 50 + 128;
1117 	}
1118 
1119 	/* Read the special DMI table for fscher and newer chips */
1120 	if ((kind == fscher || kind >= fschrc) && dmi_vref == -1) {
1121 		dmi_walk(fschmd_dmi_decode, NULL);
1122 		if (dmi_vref == -1) {
1123 			dev_warn(&client->dev,
1124 				"Couldn't get voltage scaling factors from "
1125 				"BIOS DMI table, using builtin defaults\n");
1126 			dmi_vref = 33;
1127 		}
1128 	}
1129 
1130 	/* Read in some never changing registers */
1131 	data->revision = i2c_smbus_read_byte_data(client, FSCHMD_REG_REVISION);
1132 	data->global_control = i2c_smbus_read_byte_data(client,
1133 					FSCHMD_REG_CONTROL);
1134 	data->watchdog_control = i2c_smbus_read_byte_data(client,
1135 					FSCHMD_REG_WDOG_CONTROL[data->kind]);
1136 	data->watchdog_state = i2c_smbus_read_byte_data(client,
1137 					FSCHMD_REG_WDOG_STATE[data->kind]);
1138 	data->watchdog_preset = i2c_smbus_read_byte_data(client,
1139 					FSCHMD_REG_WDOG_PRESET[data->kind]);
1140 
1141 	err = device_create_file(&client->dev, &dev_attr_alert_led);
1142 	if (err)
1143 		goto exit_detach;
1144 
1145 	for (i = 0; i < FSCHMD_NO_VOLT_SENSORS[data->kind]; i++) {
1146 		err = device_create_file(&client->dev,
1147 					&fschmd_attr[i].dev_attr);
1148 		if (err)
1149 			goto exit_detach;
1150 	}
1151 
1152 	for (i = 0; i < (FSCHMD_NO_TEMP_SENSORS[data->kind] * 4); i++) {
1153 		/* Poseidon doesn't have TEMP_LIMIT registers */
1154 		if (kind == fscpos && fschmd_temp_attr[i].dev_attr.show ==
1155 				temp_max_show)
1156 			continue;
1157 
1158 		if (kind == fscsyl) {
1159 			if (i % 4 == 0)
1160 				data->temp_status[i / 4] =
1161 					i2c_smbus_read_byte_data(client,
1162 						FSCHMD_REG_TEMP_STATE
1163 						[data->kind][i / 4]);
1164 			if (data->temp_status[i / 4] & FSCHMD_TEMP_DISABLED)
1165 				continue;
1166 		}
1167 
1168 		err = device_create_file(&client->dev,
1169 					&fschmd_temp_attr[i].dev_attr);
1170 		if (err)
1171 			goto exit_detach;
1172 	}
1173 
1174 	for (i = 0; i < (FSCHMD_NO_FAN_SENSORS[data->kind] * 5); i++) {
1175 		/* Poseidon doesn't have a FAN_MIN register for its 3rd fan */
1176 		if (kind == fscpos &&
1177 				!strcmp(fschmd_fan_attr[i].dev_attr.attr.name,
1178 					"pwm3_auto_point1_pwm"))
1179 			continue;
1180 
1181 		if (kind == fscsyl) {
1182 			if (i % 5 == 0)
1183 				data->fan_status[i / 5] =
1184 					i2c_smbus_read_byte_data(client,
1185 						FSCHMD_REG_FAN_STATE
1186 						[data->kind][i / 5]);
1187 			if (data->fan_status[i / 5] & FSCHMD_FAN_DISABLED)
1188 				continue;
1189 		}
1190 
1191 		err = device_create_file(&client->dev,
1192 					&fschmd_fan_attr[i].dev_attr);
1193 		if (err)
1194 			goto exit_detach;
1195 	}
1196 
1197 	data->hwmon_dev = hwmon_device_register(&client->dev);
1198 	if (IS_ERR(data->hwmon_dev)) {
1199 		err = PTR_ERR(data->hwmon_dev);
1200 		data->hwmon_dev = NULL;
1201 		goto exit_detach;
1202 	}
1203 
1204 	/*
1205 	 * We take the data_mutex lock early so that watchdog_open() cannot
1206 	 * run when misc_register() has completed, but we've not yet added
1207 	 * our data to the watchdog_data_list (and set the default timeout)
1208 	 */
1209 	mutex_lock(&watchdog_data_mutex);
1210 	for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) {
1211 		/* Register our watchdog part */
1212 		snprintf(data->watchdog_name, sizeof(data->watchdog_name),
1213 			"watchdog%c", (i == 0) ? '\0' : ('0' + i));
1214 		data->watchdog_miscdev.name = data->watchdog_name;
1215 		data->watchdog_miscdev.fops = &watchdog_fops;
1216 		data->watchdog_miscdev.minor = watchdog_minors[i];
1217 		err = misc_register(&data->watchdog_miscdev);
1218 		if (err == -EBUSY)
1219 			continue;
1220 		if (err) {
1221 			data->watchdog_miscdev.minor = 0;
1222 			dev_err(&client->dev,
1223 				"Registering watchdog chardev: %d\n", err);
1224 			break;
1225 		}
1226 
1227 		list_add(&data->list, &watchdog_data_list);
1228 		watchdog_set_timeout(data, 60);
1229 		dev_info(&client->dev,
1230 			"Registered watchdog chardev major 10, minor: %d\n",
1231 			watchdog_minors[i]);
1232 		break;
1233 	}
1234 	if (i == ARRAY_SIZE(watchdog_minors)) {
1235 		data->watchdog_miscdev.minor = 0;
1236 		dev_warn(&client->dev,
1237 			 "Couldn't register watchdog chardev (due to no free minor)\n");
1238 	}
1239 	mutex_unlock(&watchdog_data_mutex);
1240 
1241 	dev_info(&client->dev, "Detected FSC %s chip, revision: %d\n",
1242 		names[data->kind], (int) data->revision);
1243 
1244 	return 0;
1245 
1246 exit_detach:
1247 	fschmd_remove(client); /* will also free data for us */
1248 	return err;
1249 }
1250 
1251 static int fschmd_remove(struct i2c_client *client)
1252 {
1253 	struct fschmd_data *data = i2c_get_clientdata(client);
1254 	int i;
1255 
1256 	/* Unregister the watchdog (if registered) */
1257 	if (data->watchdog_miscdev.minor) {
1258 		misc_deregister(&data->watchdog_miscdev);
1259 		if (data->watchdog_is_open) {
1260 			dev_warn(&client->dev,
1261 				"i2c client detached with watchdog open! "
1262 				"Stopping watchdog.\n");
1263 			watchdog_stop(data);
1264 		}
1265 		mutex_lock(&watchdog_data_mutex);
1266 		list_del(&data->list);
1267 		mutex_unlock(&watchdog_data_mutex);
1268 		/* Tell the watchdog code the client is gone */
1269 		mutex_lock(&data->watchdog_lock);
1270 		data->client = NULL;
1271 		mutex_unlock(&data->watchdog_lock);
1272 	}
1273 
1274 	/*
1275 	 * Check if registered in case we're called from fschmd_detect
1276 	 * to cleanup after an error
1277 	 */
1278 	if (data->hwmon_dev)
1279 		hwmon_device_unregister(data->hwmon_dev);
1280 
1281 	device_remove_file(&client->dev, &dev_attr_alert_led);
1282 	for (i = 0; i < (FSCHMD_NO_VOLT_SENSORS[data->kind]); i++)
1283 		device_remove_file(&client->dev, &fschmd_attr[i].dev_attr);
1284 	for (i = 0; i < (FSCHMD_NO_TEMP_SENSORS[data->kind] * 4); i++)
1285 		device_remove_file(&client->dev,
1286 					&fschmd_temp_attr[i].dev_attr);
1287 	for (i = 0; i < (FSCHMD_NO_FAN_SENSORS[data->kind] * 5); i++)
1288 		device_remove_file(&client->dev,
1289 					&fschmd_fan_attr[i].dev_attr);
1290 
1291 	mutex_lock(&watchdog_data_mutex);
1292 	kref_put(&data->kref, fschmd_release_resources);
1293 	mutex_unlock(&watchdog_data_mutex);
1294 
1295 	return 0;
1296 }
1297 
1298 static struct fschmd_data *fschmd_update_device(struct device *dev)
1299 {
1300 	struct i2c_client *client = to_i2c_client(dev);
1301 	struct fschmd_data *data = i2c_get_clientdata(client);
1302 	int i;
1303 
1304 	mutex_lock(&data->update_lock);
1305 
1306 	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
1307 
1308 		for (i = 0; i < FSCHMD_NO_TEMP_SENSORS[data->kind]; i++) {
1309 			data->temp_act[i] = i2c_smbus_read_byte_data(client,
1310 					FSCHMD_REG_TEMP_ACT[data->kind][i]);
1311 			data->temp_status[i] = i2c_smbus_read_byte_data(client,
1312 					FSCHMD_REG_TEMP_STATE[data->kind][i]);
1313 
1314 			/* The fscpos doesn't have TEMP_LIMIT registers */
1315 			if (FSCHMD_REG_TEMP_LIMIT[data->kind][i])
1316 				data->temp_max[i] = i2c_smbus_read_byte_data(
1317 					client,
1318 					FSCHMD_REG_TEMP_LIMIT[data->kind][i]);
1319 
1320 			/*
1321 			 * reset alarm if the alarm condition is gone,
1322 			 * the chip doesn't do this itself
1323 			 */
1324 			if ((data->temp_status[i] & FSCHMD_TEMP_ALARM_MASK) ==
1325 					FSCHMD_TEMP_ALARM_MASK &&
1326 					data->temp_act[i] < data->temp_max[i])
1327 				i2c_smbus_write_byte_data(client,
1328 					FSCHMD_REG_TEMP_STATE[data->kind][i],
1329 					data->temp_status[i]);
1330 		}
1331 
1332 		for (i = 0; i < FSCHMD_NO_FAN_SENSORS[data->kind]; i++) {
1333 			data->fan_act[i] = i2c_smbus_read_byte_data(client,
1334 					FSCHMD_REG_FAN_ACT[data->kind][i]);
1335 			data->fan_status[i] = i2c_smbus_read_byte_data(client,
1336 					FSCHMD_REG_FAN_STATE[data->kind][i]);
1337 			data->fan_ripple[i] = i2c_smbus_read_byte_data(client,
1338 					FSCHMD_REG_FAN_RIPPLE[data->kind][i]);
1339 
1340 			/* The fscpos third fan doesn't have a fan_min */
1341 			if (FSCHMD_REG_FAN_MIN[data->kind][i])
1342 				data->fan_min[i] = i2c_smbus_read_byte_data(
1343 					client,
1344 					FSCHMD_REG_FAN_MIN[data->kind][i]);
1345 
1346 			/* reset fan status if speed is back to > 0 */
1347 			if ((data->fan_status[i] & FSCHMD_FAN_ALARM) &&
1348 					data->fan_act[i])
1349 				i2c_smbus_write_byte_data(client,
1350 					FSCHMD_REG_FAN_STATE[data->kind][i],
1351 					data->fan_status[i]);
1352 		}
1353 
1354 		for (i = 0; i < FSCHMD_NO_VOLT_SENSORS[data->kind]; i++)
1355 			data->volt[i] = i2c_smbus_read_byte_data(client,
1356 					       FSCHMD_REG_VOLT[data->kind][i]);
1357 
1358 		data->last_updated = jiffies;
1359 		data->valid = true;
1360 	}
1361 
1362 	mutex_unlock(&data->update_lock);
1363 
1364 	return data;
1365 }
1366 
1367 module_i2c_driver(fschmd_driver);
1368 
1369 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
1370 MODULE_DESCRIPTION("FSC Poseidon, Hermes, Scylla, Heracles, Heimdall, Hades "
1371 			"and Syleus driver");
1372 MODULE_LICENSE("GPL");
1373