1/* $Id: envctrl.c,v 1.1.1.1 2008/10/15 03:26:47 james26_jang Exp $
2 * envctrl.c: Temperature and Fan monitoring on Machines providing it.
3 *
4 * Copyright (C) 1998  Eddie C. Dost  (ecd@skynet.be)
5 * Copyright (C) 2000  Vinh Truong    (vinh.truong@eng.sun.com)
6 * VT - The implementation is to support Sun Microelectronics (SME) platform
7 *      environment monitoring.  SME platforms use pcf8584 as the i2c bus
8 *      controller to access pcf8591 (8-bit A/D and D/A converter) and
9 *      pcf8571 (256 x 8-bit static low-voltage RAM with I2C-bus interface).
10 *      At board level, it follows SME Firmware I2C Specification. Reference:
11 * 	http://www-eu2.semiconductors.com/pip/PCF8584P
12 * 	http://www-eu2.semiconductors.com/pip/PCF8574AP
13 * 	http://www-eu2.semiconductors.com/pip/PCF8591P
14 *
15 * EB - Added support for CP1500 Global Address and PS/Voltage monitoring.
16 * 		Eric Brower <ebrower@usa.net>
17 */
18
19#include <linux/config.h>
20#include <linux/module.h>
21#include <linux/sched.h>
22#include <linux/errno.h>
23#include <linux/delay.h>
24#include <linux/ioport.h>
25#include <linux/init.h>
26#include <linux/miscdevice.h>
27#include <linux/mm.h>
28#include <linux/slab.h>
29#include <linux/kernel.h>
30
31#include <asm/ebus.h>
32#include <asm/uaccess.h>
33#include <asm/envctrl.h>
34
35#define __KERNEL_SYSCALLS__
36static int errno;
37#include <asm/unistd.h>
38
39#define ENVCTRL_MINOR	162
40
41#define PCF8584_ADDRESS	0x55
42
43#define CONTROL_PIN	0x80
44#define CONTROL_ES0	0x40
45#define CONTROL_ES1	0x20
46#define CONTROL_ES2	0x10
47#define CONTROL_ENI	0x08
48#define CONTROL_STA	0x04
49#define CONTROL_STO	0x02
50#define CONTROL_ACK	0x01
51
52#define STATUS_PIN	0x80
53#define STATUS_STS	0x20
54#define STATUS_BER	0x10
55#define STATUS_LRB	0x08
56#define STATUS_AD0	0x08
57#define STATUS_AAB	0x04
58#define STATUS_LAB	0x02
59#define STATUS_BB	0x01
60
61/*
62 * CLK Mode Register.
63 */
64#define BUS_CLK_90	0x00
65#define BUS_CLK_45	0x01
66#define BUS_CLK_11	0x02
67#define BUS_CLK_1_5	0x03
68
69#define CLK_3		0x00
70#define CLK_4_43	0x10
71#define CLK_6		0x14
72#define CLK_8		0x18
73#define CLK_12		0x1c
74
75#define OBD_SEND_START	0xc5    /* value to generate I2c_bus START condition */
76#define OBD_SEND_STOP 	0xc3    /* value to generate I2c_bus STOP condition */
77
78/* Monitor type of i2c child device.
79 * Firmware definitions.
80 */
81#define PCF8584_MAX_CHANNELS            8
82#define PCF8584_GLOBALADDR_TYPE			6  /* global address monitor */
83#define PCF8584_FANSTAT_TYPE            3  /* fan status monitor */
84#define PCF8584_VOLTAGE_TYPE            2  /* voltage monitor    */
85#define PCF8584_TEMP_TYPE	        	1  /* temperature monitor*/
86
87/* Monitor type of i2c child device.
88 * Driver definitions.
89 */
90#define ENVCTRL_NOMON				0
91#define ENVCTRL_CPUTEMP_MON			1    /* cpu temperature monitor */
92#define ENVCTRL_CPUVOLTAGE_MON	  	2    /* voltage monitor         */
93#define ENVCTRL_FANSTAT_MON  		3    /* fan status monitor      */
94#define ENVCTRL_ETHERTEMP_MON		4    /* ethernet temperarture */
95					     /* monitor                     */
96#define ENVCTRL_VOLTAGESTAT_MON	  	5    /* voltage status monitor  */
97#define ENVCTRL_MTHRBDTEMP_MON		6    /* motherboard temperature */
98#define ENVCTRL_SCSITEMP_MON		7    /* scsi temperarture */
99#define ENVCTRL_GLOBALADDR_MON		8    /* global address */
100
101/* Child device type.
102 * Driver definitions.
103 */
104#define I2C_ADC				0    /* pcf8591 */
105#define I2C_GPIO			1    /* pcf8571 */
106
107/* Data read from child device may need to decode
108 * through a data table and a scale.
109 * Translation type as defined by firmware.
110 */
111#define ENVCTRL_TRANSLATE_NO		0
112#define ENVCTRL_TRANSLATE_PARTIAL	1
113#define ENVCTRL_TRANSLATE_COMBINED	2
114#define ENVCTRL_TRANSLATE_FULL		3     /* table[data] */
115#define ENVCTRL_TRANSLATE_SCALE		4     /* table[data]/scale */
116
117/* Driver miscellaneous definitions. */
118#define ENVCTRL_MAX_CPU			4
119#define CHANNEL_DESC_SZ			256
120
121/* Mask values for combined GlobalAddress/PowerStatus node */
122#define ENVCTRL_GLOBALADDR_ADDR_MASK 	0x1F
123#define ENVCTRL_GLOBALADDR_PSTAT_MASK	0x60
124
125/* Node 0x70 ignored on CompactPCI CP1400/1500 platforms
126 * (see envctrl_init_i2c_child)
127 */
128#define ENVCTRL_CPCI_IGNORED_NODE		0x70
129
130struct pcf8584_reg {
131	 unsigned char data;
132	 unsigned char csr;
133};
134
135/* Each child device can be monitored by up to PCF8584_MAX_CHANNELS.
136 * Property of a port or channel as defined by the firmware.
137 */
138struct pcf8584_channel {
139        unsigned char chnl_no;
140        unsigned char io_direction;
141        unsigned char type;
142        unsigned char last;
143};
144
145/* Each child device may have one or more tables of bytes to help decode
146 * data. Table property as defined by the firmware.
147 */
148struct pcf8584_tblprop {
149        unsigned int type;
150        unsigned int scale;
151        unsigned int offset; /* offset from the beginning of the table */
152        unsigned int size;
153};
154
155/* i2c child */
156struct i2c_child_t {
157	/* Either ADC or GPIO. */
158	unsigned char i2ctype;
159        unsigned long addr;
160        struct pcf8584_channel chnl_array[PCF8584_MAX_CHANNELS];
161
162	/* Channel info. */
163	unsigned int total_chnls;	/* Number of monitor channels. */
164	unsigned char fan_mask;		/* Byte mask for fan status channels. */
165	unsigned char voltage_mask;	/* Byte mask for voltage status channels. */
166        struct pcf8584_tblprop tblprop_array[PCF8584_MAX_CHANNELS];
167
168	/* Properties of all monitor channels. */
169	unsigned int total_tbls;	/* Number of monitor tables. */
170        char *tables;			/* Pointer to table(s). */
171	char chnls_desc[CHANNEL_DESC_SZ]; /* Channel description. */
172	char mon_type[PCF8584_MAX_CHANNELS];
173};
174
175volatile static struct pcf8584_reg *i2c = NULL;
176static struct i2c_child_t i2c_childlist[ENVCTRL_MAX_CPU*2];
177static unsigned char chnls_mask[] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
178static unsigned int warning_temperature = 0;
179static unsigned int shutdown_temperature = 0;
180static char read_cpu;
181
182/* Forward declarations. */
183static struct i2c_child_t *envctrl_get_i2c_child(unsigned char);
184
185/* Function description: Read a byte from an i2c controller register.
186 * Return: A byte from the passed in address.
187 */
188static inline unsigned char envctrl_readb(volatile unsigned char *p)
189{
190	return readb(p);
191}
192
193/* Function description: Write a byte to an i2c controller register.
194 * Return: Nothing.
195 */
196static inline void envctrl_writeb(unsigned char val, volatile unsigned char *p)
197{
198	writeb(val, p);
199}
200
201/* Function Description: Test the PIN bit (Pending Interrupt Not)
202 * 			 to test when serial transmission is completed .
203 * Return : None.
204 */
205static void envtrl_i2c_test_pin(void)
206{
207	int limit = 1000000;
208
209	while (--limit > 0) {
210		if (!(envctrl_readb(&i2c->csr) & STATUS_PIN))
211			break;
212		udelay(1);
213	}
214
215	if (limit <= 0)
216		printk(KERN_INFO "envctrl: Pin status will not clear.\n");
217}
218
219/* Function Description: Test busy bit.
220 * Return : None.
221 */
222static void envctrl_i2c_test_bb(void)
223{
224	int limit = 1000000;
225
226	while (--limit > 0) {
227		/* Busy bit 0 means busy. */
228		if (envctrl_readb(&i2c->csr) & STATUS_BB)
229			break;
230		udelay(1);
231	}
232
233	if (limit <= 0)
234		printk(KERN_INFO "envctrl: Busy bit will not clear.\n");
235}
236
237/* Function Description: Send the address for a read access.
238 * Return : 0 if not acknowledged, otherwise acknowledged.
239 */
240static int envctrl_i2c_read_addr(unsigned char addr)
241{
242	envctrl_i2c_test_bb();
243
244	/* Load address. */
245	envctrl_writeb(addr + 1, &i2c->data);
246
247	envctrl_i2c_test_bb();
248
249	envctrl_writeb(OBD_SEND_START, &i2c->csr);
250
251	/* Wait for PIN. */
252	envtrl_i2c_test_pin();
253
254	/* CSR 0 means acknowledged. */
255	if (!(envctrl_readb(&i2c->csr) & STATUS_LRB)) {
256		return envctrl_readb(&i2c->data);
257	} else {
258		envctrl_writeb(OBD_SEND_STOP, &i2c->csr);
259		return 0;
260	}
261}
262
263/* Function Description: Send the address for write mode.
264 * Return : None.
265 */
266static void envctrl_i2c_write_addr(unsigned char addr)
267{
268	envctrl_i2c_test_bb();
269	envctrl_writeb(addr, &i2c->data);
270
271	/* Generate Start condition. */
272	envctrl_writeb(OBD_SEND_START, &i2c->csr);
273}
274
275/* Function Description: Read 1 byte of data from addr
276 *			 set by envctrl_i2c_read_addr()
277 * Return : Data from address set by envctrl_i2c_read_addr().
278 */
279static unsigned char envctrl_i2c_read_data(void)
280{
281	envtrl_i2c_test_pin();
282	envctrl_writeb(CONTROL_ES0, &i2c->csr);  /* Send neg ack. */
283	return envctrl_readb(&i2c->data);
284}
285
286/* Function Description: Instruct the device which port to read data from.
287 * Return : None.
288 */
289static void envctrl_i2c_write_data(unsigned char port)
290{
291	envtrl_i2c_test_pin();
292	envctrl_writeb(port, &i2c->data);
293}
294
295/* Function Description: Generate Stop condition after last byte is sent.
296 * Return : None.
297 */
298static void envctrl_i2c_stop(void)
299{
300	envtrl_i2c_test_pin();
301	envctrl_writeb(OBD_SEND_STOP, &i2c->csr);
302}
303
304/* Function Description: Read adc device.
305 * Return : Data at address and port.
306 */
307static unsigned char envctrl_i2c_read_8591(unsigned char addr, unsigned char port)
308{
309	/* Send address. */
310	envctrl_i2c_write_addr(addr);
311
312	/* Setup port to read. */
313	envctrl_i2c_write_data(port);
314	envctrl_i2c_stop();
315
316	/* Read port. */
317	envctrl_i2c_read_addr(addr);
318
319	/* Do a single byte read and send stop. */
320	envctrl_i2c_read_data();
321	envctrl_i2c_stop();
322
323	return envctrl_readb(&i2c->data);
324}
325
326/* Function Description: Read gpio device.
327 * Return : Data at address.
328 */
329static unsigned char envctrl_i2c_read_8574(unsigned char addr)
330{
331	unsigned char rd;
332
333	envctrl_i2c_read_addr(addr);
334
335	/* Do a single byte read and send stop. */
336	rd = envctrl_i2c_read_data();
337	envctrl_i2c_stop();
338	return rd;
339}
340
341/* Function Description: Decode data read from an adc device using firmware
342 *                       table.
343 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
344 */
345static int envctrl_i2c_data_translate(unsigned char data, int translate_type,
346				      int scale, char *tbl, char *bufdata)
347{
348	int len = 0;
349
350	switch (translate_type) {
351	case ENVCTRL_TRANSLATE_NO:
352		/* No decode necessary. */
353		len = 1;
354		bufdata[0] = data;
355		break;
356
357	case ENVCTRL_TRANSLATE_FULL:
358		/* Decode this way: data = table[data]. */
359		len = 1;
360		bufdata[0] = tbl[data];
361		break;
362
363	case ENVCTRL_TRANSLATE_SCALE:
364		/* Decode this way: data = table[data]/scale */
365		sprintf(bufdata,"%d ", (tbl[data] * 10) / (scale));
366		len = strlen(bufdata);
367		bufdata[len - 1] = bufdata[len - 2];
368		bufdata[len - 2] = '.';
369		break;
370
371	default:
372		break;
373	};
374
375	return len;
376}
377
378/* Function Description: Read cpu-related data such as cpu temperature, voltage.
379 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
380 */
381static int envctrl_read_cpu_info(int cpu, struct i2c_child_t *pchild,
382				 char mon_type, unsigned char *bufdata)
383{
384	unsigned char data;
385	int i;
386	char *tbl, j = -1;
387
388	/* Find the right monitor type and channel. */
389	for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
390		if (pchild->mon_type[i] == mon_type) {
391			if (++j == cpu) {
392				break;
393			}
394		}
395	}
396
397	if (j != cpu)
398		return 0;
399
400        /* Read data from address and port. */
401	data = envctrl_i2c_read_8591((unsigned char)pchild->addr,
402				     (unsigned char)pchild->chnl_array[i].chnl_no);
403
404	/* Find decoding table. */
405	tbl = pchild->tables + pchild->tblprop_array[i].offset;
406
407	return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type,
408					  pchild->tblprop_array[i].scale,
409					  tbl, bufdata);
410}
411
412/* Function Description: Read noncpu-related data such as motherboard
413 *                       temperature.
414 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
415 */
416static int envctrl_read_noncpu_info(struct i2c_child_t *pchild,
417				    char mon_type, unsigned char *bufdata)
418{
419	unsigned char data;
420	int i;
421	char *tbl = NULL;
422
423	for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
424		if (pchild->mon_type[i] == mon_type)
425			break;
426	}
427
428	if (i >= PCF8584_MAX_CHANNELS)
429		return 0;
430
431        /* Read data from address and port. */
432	data = envctrl_i2c_read_8591((unsigned char)pchild->addr,
433				     (unsigned char)pchild->chnl_array[i].chnl_no);
434
435	/* Find decoding table. */
436	tbl = pchild->tables + pchild->tblprop_array[i].offset;
437
438	return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type,
439					  pchild->tblprop_array[i].scale,
440					  tbl, bufdata);
441}
442
443/* Function Description: Read fan status.
444 * Return : Always 1 byte. Status stored in bufdata.
445 */
446static int envctrl_i2c_fan_status(struct i2c_child_t *pchild,
447				  unsigned char data,
448				  char *bufdata)
449{
450	unsigned char tmp, ret = 0;
451	int i, j = 0;
452
453	tmp = data & pchild->fan_mask;
454
455	if (tmp == pchild->fan_mask) {
456		/* All bits are on. All fans are functioning. */
457		ret = ENVCTRL_ALL_FANS_GOOD;
458	} else if (tmp == 0) {
459		/* No bits are on. No fans are functioning. */
460		ret = ENVCTRL_ALL_FANS_BAD;
461	} else {
462		/* Go through all channels, mark 'on' the matched bits.
463		 * Notice that fan_mask may have discontiguous bits but
464		 * return mask are always contiguous. For example if we
465		 * monitor 4 fans at channels 0,1,2,4, the return mask
466		 * should be 00010000 if only fan at channel 4 is working.
467		 */
468		for (i = 0; i < PCF8584_MAX_CHANNELS;i++) {
469			if (pchild->fan_mask & chnls_mask[i]) {
470				if (!(chnls_mask[i] & tmp))
471					ret |= chnls_mask[j];
472
473				j++;
474			}
475		}
476	}
477
478	bufdata[0] = ret;
479	return 1;
480}
481
482/* Function Description: Read global addressing line.
483 * Return : Always 1 byte. Status stored in bufdata.
484 */
485static int envctrl_i2c_globaladdr(struct i2c_child_t *pchild,
486				  unsigned char data,
487				  char *bufdata)
488{
489	/* Translatation table is not necessary, as global
490	 * addr is the integer value of the GA# bits.
491	 *
492	 * NOTE: MSB is documented as zero, but I see it as '1' always....
493	 *
494	 * -----------------------------------------------
495	 * | 0 | FAL | DEG | GA4 | GA3 | GA2 | GA1 | GA0 |
496	 * -----------------------------------------------
497	 * GA0 - GA4	integer value of Global Address (backplane slot#)
498	 * DEG			0 = cPCI Power supply output is starting to degrade
499	 * 				1 = cPCI Power supply output is OK
500	 * FAL			0 = cPCI Power supply has failed
501	 * 				1 = cPCI Power supply output is OK
502	 */
503	bufdata[0] = (data & ENVCTRL_GLOBALADDR_ADDR_MASK);
504	return 1;
505}
506
507/* Function Description: Read standard voltage and power supply status.
508 * Return : Always 1 byte. Status stored in bufdata.
509 */
510static unsigned char envctrl_i2c_voltage_status(struct i2c_child_t *pchild,
511						unsigned char data,
512						char *bufdata)
513{
514	unsigned char tmp, ret = 0;
515	int i, j = 0;
516
517	tmp = data & pchild->voltage_mask;
518
519	/* Two channels are used to monitor voltage and power supply. */
520	if (tmp == pchild->voltage_mask) {
521		/* All bits are on. Voltage and power supply are okay. */
522		ret = ENVCTRL_VOLTAGE_POWERSUPPLY_GOOD;
523	} else if (tmp == 0) {
524		/* All bits are off. Voltage and power supply are bad */
525		ret = ENVCTRL_VOLTAGE_POWERSUPPLY_BAD;
526	} else {
527		/* Either voltage or power supply has problem. */
528		for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
529			if (pchild->voltage_mask & chnls_mask[i]) {
530				j++;
531
532				/* Break out when there is a mismatch. */
533				if (!(chnls_mask[i] & tmp))
534					break;
535			}
536		}
537
538		/* Make a wish that hardware will always use the
539		 * first channel for voltage and the second for
540		 * power supply.
541		 */
542		if (j == 1)
543			ret = ENVCTRL_VOLTAGE_BAD;
544		else
545			ret = ENVCTRL_POWERSUPPLY_BAD;
546	}
547
548	bufdata[0] = ret;
549	return 1;
550}
551
552/* Function Description: Read a byte from /dev/envctrl. Mapped to user read().
553 * Return: Number of read bytes. 0 for error.
554 */
555static ssize_t
556envctrl_read(struct file *file, char *buf, size_t count, loff_t *ppos)
557{
558	struct i2c_child_t *pchild;
559	unsigned char data[10];
560	int ret = 0;
561
562	/* Get the type of read as decided in ioctl() call.
563	 * Find the appropriate i2c child.
564	 * Get the data and put back to the user buffer.
565	 */
566
567	switch ((int)(long)file->private_data) {
568	case ENVCTRL_RD_WARNING_TEMPERATURE:
569		if (warning_temperature == 0)
570			return 0;
571
572		data[0] = (unsigned char)(warning_temperature);
573		ret = 1;
574		copy_to_user((unsigned char *)buf, data, ret);
575		break;
576
577	case ENVCTRL_RD_SHUTDOWN_TEMPERATURE:
578		if (shutdown_temperature == 0)
579			return 0;
580
581		data[0] = (unsigned char)(shutdown_temperature);
582		ret = 1;
583		copy_to_user((unsigned char *)buf, data, ret);
584		break;
585
586	case ENVCTRL_RD_MTHRBD_TEMPERATURE:
587		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_MTHRBDTEMP_MON)))
588			return 0;
589		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_MTHRBDTEMP_MON, data);
590		copy_to_user((unsigned char *)buf, data, ret);
591		break;
592
593	case ENVCTRL_RD_CPU_TEMPERATURE:
594		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON)))
595			return 0;
596		ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUTEMP_MON, data);
597
598		/* Reset cpu to the default cpu0. */
599		copy_to_user((unsigned char *)buf, data, ret);
600		break;
601
602	case ENVCTRL_RD_CPU_VOLTAGE:
603		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUVOLTAGE_MON)))
604			return 0;
605		ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUVOLTAGE_MON, data);
606
607		/* Reset cpu to the default cpu0. */
608		copy_to_user((unsigned char *)buf, data, ret);
609		break;
610
611	case ENVCTRL_RD_SCSI_TEMPERATURE:
612		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_SCSITEMP_MON)))
613			return 0;
614		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_SCSITEMP_MON, data);
615		copy_to_user((unsigned char *)buf, data, ret);
616		break;
617
618	case ENVCTRL_RD_ETHERNET_TEMPERATURE:
619		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_ETHERTEMP_MON)))
620			return 0;
621		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_ETHERTEMP_MON, data);
622		copy_to_user((unsigned char *)buf, data, ret);
623		break;
624
625	case ENVCTRL_RD_FAN_STATUS:
626		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_FANSTAT_MON)))
627			return 0;
628		data[0] = envctrl_i2c_read_8574(pchild->addr);
629		ret = envctrl_i2c_fan_status(pchild,data[0], data);
630		copy_to_user((unsigned char *)buf, data, ret);
631		break;
632
633	case ENVCTRL_RD_GLOBALADDRESS:
634		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_GLOBALADDR_MON)))
635			return 0;
636		data[0] = envctrl_i2c_read_8574(pchild->addr);
637		ret = envctrl_i2c_globaladdr(pchild, data[0], data);
638		copy_to_user((unsigned char *)buf, data, ret);
639		break;
640
641	case ENVCTRL_RD_VOLTAGE_STATUS:
642		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_VOLTAGESTAT_MON)))
643			/* If voltage monitor not present, check for CPCI equivalent */
644			if (!(pchild = envctrl_get_i2c_child(ENVCTRL_GLOBALADDR_MON)))
645				return 0;
646		data[0] = envctrl_i2c_read_8574(pchild->addr);
647		ret = envctrl_i2c_voltage_status(pchild, data[0], data);
648		copy_to_user((unsigned char *)buf, data, ret);
649		break;
650
651	default:
652		break;
653
654	};
655
656	return ret;
657}
658
659/* Function Description: Command what to read.  Mapped to user ioctl().
660 * Return: Gives 0 for implemented commands, -EINVAL otherwise.
661 */
662static int
663envctrl_ioctl(struct inode *inode, struct file *file,
664	      unsigned int cmd, unsigned long arg)
665{
666	char *infobuf;
667
668	switch (cmd) {
669	case ENVCTRL_RD_WARNING_TEMPERATURE:
670	case ENVCTRL_RD_SHUTDOWN_TEMPERATURE:
671	case ENVCTRL_RD_MTHRBD_TEMPERATURE:
672	case ENVCTRL_RD_FAN_STATUS:
673	case ENVCTRL_RD_VOLTAGE_STATUS:
674	case ENVCTRL_RD_ETHERNET_TEMPERATURE:
675	case ENVCTRL_RD_SCSI_TEMPERATURE:
676	case ENVCTRL_RD_GLOBALADDRESS:
677		file->private_data = (void *)(long)cmd;
678		break;
679
680	case ENVCTRL_RD_CPU_TEMPERATURE:
681	case ENVCTRL_RD_CPU_VOLTAGE:
682		/* Check to see if application passes in any cpu number,
683		 * the default is cpu0.
684		 */
685		infobuf = (char *) arg;
686		if (infobuf == NULL) {
687			read_cpu = 0;
688		}else {
689			get_user(read_cpu, infobuf);
690		}
691
692		/* Save the command for use when reading. */
693		file->private_data = (void *)(long)cmd;
694		break;
695
696	default:
697		return -EINVAL;
698	};
699
700	return 0;
701}
702
703/* Function Description: open device. Mapped to user open().
704 * Return: Always 0.
705 */
706static int
707envctrl_open(struct inode *inode, struct file *file)
708{
709	file->private_data = 0;
710	MOD_INC_USE_COUNT;
711	return 0;
712}
713
714/* Function Description: Open device. Mapped to user close().
715 * Return: Always 0.
716 */
717static int
718envctrl_release(struct inode *inode, struct file *file)
719{
720	MOD_DEC_USE_COUNT;
721	return 0;
722}
723
724static struct file_operations envctrl_fops = {
725	owner:		THIS_MODULE,
726	read:		envctrl_read,
727	ioctl:		envctrl_ioctl,
728	open:		envctrl_open,
729	release:	envctrl_release,
730};
731
732static struct miscdevice envctrl_dev = {
733	ENVCTRL_MINOR,
734	"envctrl",
735	&envctrl_fops
736};
737
738/* Function Description: Set monitor type based on firmware description.
739 * Return: None.
740 */
741static void envctrl_set_mon(struct i2c_child_t *pchild,
742			    char *chnl_desc,
743			    int chnl_no)
744{
745	/* Firmware only has temperature type.  It does not distinguish
746	 * different kinds of temperatures.  We use channel description
747	 * to disinguish them.
748	 */
749	if (!(strcmp(chnl_desc,"temp,cpu")) ||
750	    !(strcmp(chnl_desc,"temp,cpu0")) ||
751	    !(strcmp(chnl_desc,"temp,cpu1")) ||
752	    !(strcmp(chnl_desc,"temp,cpu2")) ||
753	    !(strcmp(chnl_desc,"temp,cpu3")))
754		pchild->mon_type[chnl_no] = ENVCTRL_CPUTEMP_MON;
755
756	if (!(strcmp(chnl_desc,"vddcore,cpu0")) ||
757	    !(strcmp(chnl_desc,"vddcore,cpu1")) ||
758	    !(strcmp(chnl_desc,"vddcore,cpu2")) ||
759	    !(strcmp(chnl_desc,"vddcore,cpu3")))
760		pchild->mon_type[chnl_no] = ENVCTRL_CPUVOLTAGE_MON;
761
762	if (!(strcmp(chnl_desc,"temp,motherboard")))
763		pchild->mon_type[chnl_no] = ENVCTRL_MTHRBDTEMP_MON;
764
765	if (!(strcmp(chnl_desc,"temp,scsi")))
766		pchild->mon_type[chnl_no] = ENVCTRL_SCSITEMP_MON;
767
768	if (!(strcmp(chnl_desc,"temp,ethernet")))
769		pchild->mon_type[chnl_no] = ENVCTRL_ETHERTEMP_MON;
770}
771
772/* Function Description: Initialize monitor channel with channel desc,
773 *                       decoding tables, monitor type, optional properties.
774 * Return: None.
775 */
776static void envctrl_init_adc(struct i2c_child_t *pchild, int node)
777{
778	char chnls_desc[CHANNEL_DESC_SZ];
779	int i = 0, len;
780	char *pos = chnls_desc;
781
782	/* Firmware describe channels into a stream separated by a '\0'. */
783	len = prom_getproperty(node, "channels-description", chnls_desc,
784			       CHANNEL_DESC_SZ);
785	chnls_desc[CHANNEL_DESC_SZ - 1] = '\0';
786
787	while (len > 0) {
788		int l = strlen(pos) + 1;
789		envctrl_set_mon(pchild, pos, i++);
790		len -= l;
791		pos += l;
792	}
793
794	/* Get optional properties. */
795        len = prom_getproperty(node, "warning-temp", (char *)&warning_temperature,
796			       sizeof(warning_temperature));
797        len = prom_getproperty(node, "shutdown-temp", (char *)&shutdown_temperature,
798			       sizeof(shutdown_temperature));
799}
800
801/* Function Description: Initialize child device monitoring fan status.
802 * Return: None.
803 */
804static void envctrl_init_fanstat(struct i2c_child_t *pchild)
805{
806	int i;
807
808	/* Go through all channels and set up the mask. */
809	for (i = 0; i < pchild->total_chnls; i++)
810		pchild->fan_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];
811
812	/* We only need to know if this child has fan status monitored.
813	 * We dont care which channels since we have the mask already.
814	 */
815	pchild->mon_type[0] = ENVCTRL_FANSTAT_MON;
816}
817
818/* Function Description: Initialize child device for global addressing line.
819 * Return: None.
820 */
821static void envctrl_init_globaladdr(struct i2c_child_t *pchild)
822{
823	int i;
824
825	/* Voltage/PowerSupply monitoring is piggybacked
826	 * with Global Address on CompactPCI.  See comments
827	 * within envctrl_i2c_globaladdr for bit assignments.
828	 *
829	 * The mask is created here by assigning mask bits to each
830	 * bit position that represents PCF8584_VOLTAGE_TYPE data.
831	 * Channel numbers are not consecutive within the globaladdr
832	 * node (why?), so we use the actual counter value as chnls_mask
833	 * index instead of the chnl_array[x].chnl_no value.
834	 *
835	 * NOTE: This loop could be replaced with a constant representing
836	 * a mask of bits 5&6 (ENVCTRL_GLOBALADDR_PSTAT_MASK).
837	 */
838	for (i = 0; i < pchild->total_chnls; i++) {
839		if (PCF8584_VOLTAGE_TYPE == pchild->chnl_array[i].type) {
840			pchild->voltage_mask |= chnls_mask[i];
841		}
842	}
843
844	/* We only need to know if this child has global addressing
845	 * line monitored.  We dont care which channels since we know
846	 * the mask already (ENVCTRL_GLOBALADDR_ADDR_MASK).
847	 */
848	pchild->mon_type[0] = ENVCTRL_GLOBALADDR_MON;
849}
850
851/* Initialize child device monitoring voltage status. */
852static void envctrl_init_voltage_status(struct i2c_child_t *pchild)
853{
854	int i;
855
856	/* Go through all channels and set up the mask. */
857	for (i = 0; i < pchild->total_chnls; i++)
858		pchild->voltage_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];
859
860	/* We only need to know if this child has voltage status monitored.
861	 * We dont care which channels since we have the mask already.
862	 */
863	pchild->mon_type[0] = ENVCTRL_VOLTAGESTAT_MON;
864}
865
866/* Function Description: Initialize i2c child device.
867 * Return: None.
868 */
869static void envctrl_init_i2c_child(struct linux_ebus_child *edev_child,
870				   struct i2c_child_t *pchild)
871{
872	int node, len, i, tbls_size = 0;
873
874	node = edev_child->prom_node;
875
876	/* Get device address. */
877	len = prom_getproperty(node, "reg",
878			       (char *) &(pchild->addr),
879			       sizeof(pchild->addr));
880
881	/* Get tables property.  Read firmware temperature tables. */
882	len = prom_getproperty(node, "translation",
883			       (char *) pchild->tblprop_array,
884			       (PCF8584_MAX_CHANNELS *
885				sizeof(struct pcf8584_tblprop)));
886	if (len > 0) {
887                pchild->total_tbls = len / sizeof(struct pcf8584_tblprop);
888		for (i = 0; i < pchild->total_tbls; i++) {
889			if ((pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset) > tbls_size) {
890				tbls_size = pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset;
891			}
892		}
893
894                pchild->tables = kmalloc(tbls_size, GFP_KERNEL);
895                len = prom_getproperty(node, "tables",
896				       (char *) pchild->tables, tbls_size);
897                if (len <= 0) {
898			printk("envctrl: Failed to get table.\n");
899			return;
900		}
901	}
902
903	/* SPARCengine ASM Reference Manual (ref. SMI doc 805-7581-04)
904	 * sections 2.5, 3.5, 4.5 state node 0x70 for CP1400/1500 is
905	 * "For Factory Use Only."
906	 *
907	 * We ignore the node on these platforms by assigning the
908	 * 'NULL' monitor type.
909	 */
910	if (ENVCTRL_CPCI_IGNORED_NODE == pchild->addr) {
911		int len;
912		char prop[56];
913
914		len = prom_getproperty(prom_root_node, "name", prop, sizeof(prop));
915		if (0 < len && (0 == strncmp(prop, "SUNW,UltraSPARC-IIi-cEngine", len)))
916		{
917			for (len = 0; len < PCF8584_MAX_CHANNELS; ++len) {
918				pchild->mon_type[len] = ENVCTRL_NOMON;
919			}
920			return;
921		}
922	}
923
924	/* Get the monitor channels. */
925	len = prom_getproperty(node, "channels-in-use",
926			       (char *) pchild->chnl_array,
927			       (PCF8584_MAX_CHANNELS *
928				sizeof(struct pcf8584_channel)));
929	pchild->total_chnls = len / sizeof(struct pcf8584_channel);
930
931	for (i = 0; i < pchild->total_chnls; i++) {
932		switch (pchild->chnl_array[i].type) {
933		case PCF8584_TEMP_TYPE:
934			envctrl_init_adc(pchild, node);
935			break;
936
937		case PCF8584_GLOBALADDR_TYPE:
938			envctrl_init_globaladdr(pchild);
939			i = pchild->total_chnls;
940			break;
941
942		case PCF8584_FANSTAT_TYPE:
943			envctrl_init_fanstat(pchild);
944			i = pchild->total_chnls;
945			break;
946
947		case PCF8584_VOLTAGE_TYPE:
948			if (pchild->i2ctype == I2C_ADC) {
949				envctrl_init_adc(pchild,node);
950			} else {
951				envctrl_init_voltage_status(pchild);
952			}
953			i = pchild->total_chnls;
954			break;
955
956		default:
957			break;
958		};
959	}
960}
961
962/* Function Description: Search the child device list for a device.
963 * Return : The i2c child if found. NULL otherwise.
964 */
965static struct i2c_child_t *envctrl_get_i2c_child(unsigned char mon_type)
966{
967	int i, j;
968
969	for (i = 0; i < ENVCTRL_MAX_CPU*2; i++) {
970		for (j = 0; j < PCF8584_MAX_CHANNELS; j++) {
971			if (i2c_childlist[i].mon_type[j] == mon_type) {
972				return (struct i2c_child_t *)(&(i2c_childlist[i]));
973			}
974		}
975	}
976	return NULL;
977}
978
979static void envctrl_do_shutdown(void)
980{
981	static int inprog = 0;
982	static char *envp[] = {
983		"HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
984	char *argv[] = {
985		"/sbin/shutdown", "-h", "now", NULL };
986
987	if (inprog != 0)
988		return;
989
990	inprog = 1;
991	printk(KERN_CRIT "kenvctrld: WARNING: Shutting down the system now.\n");
992	if (0 > execve("/sbin/shutdown", argv, envp)) {
993		printk(KERN_CRIT "kenvctrld: WARNING: system shutdown failed!\n");
994		inprog = 0;  /* unlikely to succeed, but we could try again */
995	}
996}
997
998static struct task_struct *kenvctrld_task;
999
1000static int kenvctrld(void *__unused)
1001{
1002	int poll_interval;
1003	int whichcpu;
1004	char tempbuf[10];
1005	struct i2c_child_t *cputemp;
1006
1007	if (NULL == (cputemp = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON))) {
1008		printk(KERN_ERR
1009		       "envctrl: kenvctrld unable to monitor CPU temp-- exiting\n");
1010		return -ENODEV;
1011	}
1012
1013	poll_interval = 5 * HZ; /* TODO env_mon_interval */
1014
1015	daemonize();
1016	strcpy(current->comm, "kenvctrld");
1017	kenvctrld_task = current;
1018
1019	printk(KERN_INFO "envctrl: %s starting...\n", current->comm);
1020	for (;;) {
1021		current->state = TASK_INTERRUPTIBLE;
1022		schedule_timeout(poll_interval);
1023		current->state = TASK_RUNNING;
1024
1025		if(signal_pending(current))
1026			break;
1027
1028		for (whichcpu = 0; whichcpu < ENVCTRL_MAX_CPU; ++whichcpu) {
1029			if (0 < envctrl_read_cpu_info(whichcpu, cputemp,
1030						      ENVCTRL_CPUTEMP_MON,
1031						      tempbuf)) {
1032				if (tempbuf[0] >= shutdown_temperature) {
1033					printk(KERN_CRIT
1034						"%s: WARNING: CPU%i temperature %i C meets or exceeds "\
1035						"shutdown threshold %i C\n",
1036						current->comm, whichcpu,
1037						tempbuf[0], shutdown_temperature);
1038					envctrl_do_shutdown();
1039				}
1040			}
1041		}
1042	}
1043	printk(KERN_INFO "envctrl: %s exiting...\n", current->comm);
1044	return 0;
1045}
1046
1047static int __init envctrl_init(void)
1048{
1049#ifdef CONFIG_PCI
1050	struct linux_ebus *ebus = NULL;
1051	struct linux_ebus_device *edev = NULL;
1052	struct linux_ebus_child *edev_child = NULL;
1053	int i = 0;
1054
1055	for_each_ebus(ebus) {
1056		for_each_ebusdev(edev, ebus) {
1057			if (!strcmp(edev->prom_name, "bbc")) {
1058				/* If we find a boot-bus controller node,
1059				 * then this envctrl driver is not for us.
1060				 */
1061				return -ENODEV;
1062			}
1063		}
1064	}
1065
1066	/* Traverse through ebus and ebus device list for i2c device and
1067	 * adc and gpio nodes.
1068	 */
1069	for_each_ebus(ebus) {
1070		for_each_ebusdev(edev, ebus) {
1071			if (!strcmp(edev->prom_name, "i2c")) {
1072				i2c = ioremap(	edev->resource[0].start,
1073								sizeof(struct pcf8584_reg));
1074				for_each_edevchild(edev, edev_child) {
1075					if (!strcmp("gpio", edev_child->prom_name)) {
1076						i2c_childlist[i].i2ctype = I2C_GPIO;
1077						envctrl_init_i2c_child(edev_child, &(i2c_childlist[i++]));
1078					}
1079					if (!strcmp("adc", edev_child->prom_name)) {
1080						i2c_childlist[i].i2ctype = I2C_ADC;
1081						envctrl_init_i2c_child(edev_child, &(i2c_childlist[i++]));
1082					}
1083				}
1084				goto done;
1085			}
1086		}
1087	}
1088
1089done:
1090	if (!edev) {
1091		printk("envctrl: I2C device not found.\n");
1092		return -ENODEV;
1093	}
1094
1095	/* Set device address. */
1096	envctrl_writeb(CONTROL_PIN, &i2c->csr);
1097	envctrl_writeb(PCF8584_ADDRESS, &i2c->data);
1098
1099	/* Set system clock and SCL frequencies. */
1100	envctrl_writeb(CONTROL_PIN | CONTROL_ES1, &i2c->csr);
1101	envctrl_writeb(CLK_4_43 | BUS_CLK_90, &i2c->data);
1102
1103	/* Enable serial interface. */
1104	envctrl_writeb(CONTROL_PIN | CONTROL_ES0 | CONTROL_ACK, &i2c->csr);
1105	udelay(200);
1106
1107	/* Register the device as a minor miscellaneous device. */
1108	if (misc_register(&envctrl_dev)) {
1109		printk("envctrl: Unable to get misc minor %d\n",
1110		       envctrl_dev.minor);
1111	}
1112
1113	/* Note above traversal routine post-incremented 'i' to accomodate
1114	 * a next child device, so we decrement before reverse-traversal of
1115	 * child devices.
1116	 */
1117	printk("envctrl: initialized ");
1118	for (--i; i >= 0; --i) {
1119		printk("[%s 0x%lx]%s",
1120			(I2C_ADC == i2c_childlist[i].i2ctype) ? ("adc") :
1121			((I2C_GPIO == i2c_childlist[i].i2ctype) ? ("gpio") : ("unknown")),
1122			i2c_childlist[i].addr, (0 == i) ? ("\n") : (" "));
1123	}
1124
1125	kernel_thread(kenvctrld, NULL, CLONE_FS | CLONE_FILES);
1126
1127	return 0;
1128#else
1129	return -ENODEV;
1130#endif
1131}
1132
1133static void __exit envctrl_cleanup(void)
1134{
1135	int i;
1136
1137	if (NULL != kenvctrld_task) {
1138		force_sig(SIGKILL, kenvctrld_task);
1139		for (;;) {
1140			struct task_struct *p;
1141			int found = 0;
1142
1143			read_lock(&tasklist_lock);
1144			for_each_task(p) {
1145				if (p == kenvctrld_task) {
1146					found = 1;
1147					break;
1148				}
1149			}
1150			read_unlock(&tasklist_lock);
1151
1152			if (!found)
1153				break;
1154
1155			current->state = TASK_INTERRUPTIBLE;
1156			schedule_timeout(HZ);
1157			current->state = TASK_RUNNING;
1158		}
1159		kenvctrld_task = NULL;
1160	}
1161
1162	iounmap(i2c);
1163	misc_deregister(&envctrl_dev);
1164
1165	for (i = 0; i < ENVCTRL_MAX_CPU * 2; i++) {
1166		if (i2c_childlist[i].tables)
1167			kfree(i2c_childlist[i].tables);
1168	}
1169}
1170
1171module_init(envctrl_init);
1172module_exit(envctrl_cleanup);
1173MODULE_LICENSE("GPL");
1174