1// SPDX-License-Identifier: GPL-2.0-only
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 * DB - Audit every copy_to_user in envctrl_read.
19 *              Daniele Bellucci <bellucda@tiscali.it>
20 */
21
22#include <linux/module.h>
23#include <linux/kthread.h>
24#include <linux/delay.h>
25#include <linux/ioport.h>
26#include <linux/miscdevice.h>
27#include <linux/kmod.h>
28#include <linux/reboot.h>
29#include <linux/slab.h>
30#include <linux/of.h>
31#include <linux/platform_device.h>
32
33#include <linux/uaccess.h>
34#include <asm/envctrl.h>
35#include <asm/io.h>
36
37#define DRIVER_NAME	"envctrl"
38#define PFX		DRIVER_NAME ": "
39
40#define PCF8584_ADDRESS	0x55
41
42#define CONTROL_PIN	0x80
43#define CONTROL_ES0	0x40
44#define CONTROL_ES1	0x20
45#define CONTROL_ES2	0x10
46#define CONTROL_ENI	0x08
47#define CONTROL_STA	0x04
48#define CONTROL_STO	0x02
49#define CONTROL_ACK	0x01
50
51#define STATUS_PIN	0x80
52#define STATUS_STS	0x20
53#define STATUS_BER	0x10
54#define STATUS_LRB	0x08
55#define STATUS_AD0	0x08
56#define STATUS_AAB	0x04
57#define STATUS_LAB	0x02
58#define STATUS_BB	0x01
59
60/*
61 * CLK Mode Register.
62 */
63#define BUS_CLK_90	0x00
64#define BUS_CLK_45	0x01
65#define BUS_CLK_11	0x02
66#define BUS_CLK_1_5	0x03
67
68#define CLK_3		0x00
69#define CLK_4_43	0x10
70#define CLK_6		0x14
71#define CLK_8		0x18
72#define CLK_12		0x1c
73
74#define OBD_SEND_START	0xc5    /* value to generate I2c_bus START condition */
75#define OBD_SEND_STOP 	0xc3    /* value to generate I2c_bus STOP condition */
76
77/* Monitor type of i2c child device.
78 * Firmware definitions.
79 */
80#define PCF8584_MAX_CHANNELS            8
81#define PCF8584_GLOBALADDR_TYPE			6  /* global address monitor */
82#define PCF8584_FANSTAT_TYPE            3  /* fan status monitor */
83#define PCF8584_VOLTAGE_TYPE            2  /* voltage monitor    */
84#define PCF8584_TEMP_TYPE	        	1  /* temperature monitor*/
85
86/* Monitor type of i2c child device.
87 * Driver definitions.
88 */
89#define ENVCTRL_NOMON				0
90#define ENVCTRL_CPUTEMP_MON			1    /* cpu temperature monitor */
91#define ENVCTRL_CPUVOLTAGE_MON	  	2    /* voltage monitor         */
92#define ENVCTRL_FANSTAT_MON  		3    /* fan status monitor      */
93#define ENVCTRL_ETHERTEMP_MON		4    /* ethernet temperature */
94					     /* monitor                     */
95#define ENVCTRL_VOLTAGESTAT_MON	  	5    /* voltage status monitor  */
96#define ENVCTRL_MTHRBDTEMP_MON		6    /* motherboard temperature */
97#define ENVCTRL_SCSITEMP_MON		7    /* scsi temperature */
98#define ENVCTRL_GLOBALADDR_MON		8    /* global address */
99
100/* Child device type.
101 * Driver definitions.
102 */
103#define I2C_ADC				0    /* pcf8591 */
104#define I2C_GPIO			1    /* pcf8571 */
105
106/* Data read from child device may need to decode
107 * through a data table and a scale.
108 * Translation type as defined by firmware.
109 */
110#define ENVCTRL_TRANSLATE_NO		0
111#define ENVCTRL_TRANSLATE_PARTIAL	1
112#define ENVCTRL_TRANSLATE_COMBINED	2
113#define ENVCTRL_TRANSLATE_FULL		3     /* table[data] */
114#define ENVCTRL_TRANSLATE_SCALE		4     /* table[data]/scale */
115
116/* Driver miscellaneous definitions. */
117#define ENVCTRL_MAX_CPU			4
118#define CHANNEL_DESC_SZ			256
119
120/* Mask values for combined GlobalAddress/PowerStatus node */
121#define ENVCTRL_GLOBALADDR_ADDR_MASK 	0x1F
122#define ENVCTRL_GLOBALADDR_PSTAT_MASK	0x60
123
124/* Node 0x70 ignored on CompactPCI CP1400/1500 platforms
125 * (see envctrl_init_i2c_child)
126 */
127#define ENVCTRL_CPCI_IGNORED_NODE		0x70
128
129#define PCF8584_DATA	0x00
130#define PCF8584_CSR	0x01
131
132/* Each child device can be monitored by up to PCF8584_MAX_CHANNELS.
133 * Property of a port or channel as defined by the firmware.
134 */
135struct pcf8584_channel {
136        unsigned char chnl_no;
137        unsigned char io_direction;
138        unsigned char type;
139        unsigned char last;
140};
141
142/* Each child device may have one or more tables of bytes to help decode
143 * data. Table property as defined by the firmware.
144 */
145struct pcf8584_tblprop {
146        unsigned int type;
147        unsigned int scale;
148        unsigned int offset; /* offset from the beginning of the table */
149        unsigned int size;
150};
151
152/* i2c child */
153struct i2c_child_t {
154	/* Either ADC or GPIO. */
155	unsigned char i2ctype;
156        unsigned long addr;
157        struct pcf8584_channel chnl_array[PCF8584_MAX_CHANNELS];
158
159	/* Channel info. */
160	unsigned int total_chnls;	/* Number of monitor channels. */
161	unsigned char fan_mask;		/* Byte mask for fan status channels. */
162	unsigned char voltage_mask;	/* Byte mask for voltage status channels. */
163        struct pcf8584_tblprop tblprop_array[PCF8584_MAX_CHANNELS];
164
165	/* Properties of all monitor channels. */
166	unsigned int total_tbls;	/* Number of monitor tables. */
167        char *tables;			/* Pointer to table(s). */
168	char chnls_desc[CHANNEL_DESC_SZ]; /* Channel description. */
169	char mon_type[PCF8584_MAX_CHANNELS];
170};
171
172static void __iomem *i2c;
173static struct i2c_child_t i2c_childlist[ENVCTRL_MAX_CPU*2];
174static unsigned char chnls_mask[] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
175static unsigned int warning_temperature = 0;
176static unsigned int shutdown_temperature = 0;
177static char read_cpu;
178
179/* Forward declarations. */
180static struct i2c_child_t *envctrl_get_i2c_child(unsigned char);
181
182/* Function Description: Test the PIN bit (Pending Interrupt Not)
183 * 			 to test when serial transmission is completed .
184 * Return : None.
185 */
186static void envtrl_i2c_test_pin(void)
187{
188	int limit = 1000000;
189
190	while (--limit > 0) {
191		if (!(readb(i2c + PCF8584_CSR) & STATUS_PIN))
192			break;
193		udelay(1);
194	}
195
196	if (limit <= 0)
197		printk(KERN_INFO PFX "Pin status will not clear.\n");
198}
199
200/* Function Description: Test busy bit.
201 * Return : None.
202 */
203static void envctrl_i2c_test_bb(void)
204{
205	int limit = 1000000;
206
207	while (--limit > 0) {
208		/* Busy bit 0 means busy. */
209		if (readb(i2c + PCF8584_CSR) & STATUS_BB)
210			break;
211		udelay(1);
212	}
213
214	if (limit <= 0)
215		printk(KERN_INFO PFX "Busy bit will not clear.\n");
216}
217
218/* Function Description: Send the address for a read access.
219 * Return : 0 if not acknowledged, otherwise acknowledged.
220 */
221static int envctrl_i2c_read_addr(unsigned char addr)
222{
223	envctrl_i2c_test_bb();
224
225	/* Load address. */
226	writeb(addr + 1, i2c + PCF8584_DATA);
227
228	envctrl_i2c_test_bb();
229
230	writeb(OBD_SEND_START, i2c + PCF8584_CSR);
231
232	/* Wait for PIN. */
233	envtrl_i2c_test_pin();
234
235	/* CSR 0 means acknowledged. */
236	if (!(readb(i2c + PCF8584_CSR) & STATUS_LRB)) {
237		return readb(i2c + PCF8584_DATA);
238	} else {
239		writeb(OBD_SEND_STOP, i2c + PCF8584_CSR);
240		return 0;
241	}
242}
243
244/* Function Description: Send the address for write mode.
245 * Return : None.
246 */
247static void envctrl_i2c_write_addr(unsigned char addr)
248{
249	envctrl_i2c_test_bb();
250	writeb(addr, i2c + PCF8584_DATA);
251
252	/* Generate Start condition. */
253	writeb(OBD_SEND_START, i2c + PCF8584_CSR);
254}
255
256/* Function Description: Read 1 byte of data from addr
257 *			 set by envctrl_i2c_read_addr()
258 * Return : Data from address set by envctrl_i2c_read_addr().
259 */
260static unsigned char envctrl_i2c_read_data(void)
261{
262	envtrl_i2c_test_pin();
263	writeb(CONTROL_ES0, i2c + PCF8584_CSR);  /* Send neg ack. */
264	return readb(i2c + PCF8584_DATA);
265}
266
267/* Function Description: Instruct the device which port to read data from.
268 * Return : None.
269 */
270static void envctrl_i2c_write_data(unsigned char port)
271{
272	envtrl_i2c_test_pin();
273	writeb(port, i2c + PCF8584_DATA);
274}
275
276/* Function Description: Generate Stop condition after last byte is sent.
277 * Return : None.
278 */
279static void envctrl_i2c_stop(void)
280{
281	envtrl_i2c_test_pin();
282	writeb(OBD_SEND_STOP, i2c + PCF8584_CSR);
283}
284
285/* Function Description: Read adc device.
286 * Return : Data at address and port.
287 */
288static unsigned char envctrl_i2c_read_8591(unsigned char addr, unsigned char port)
289{
290	/* Send address. */
291	envctrl_i2c_write_addr(addr);
292
293	/* Setup port to read. */
294	envctrl_i2c_write_data(port);
295	envctrl_i2c_stop();
296
297	/* Read port. */
298	envctrl_i2c_read_addr(addr);
299
300	/* Do a single byte read and send stop. */
301	envctrl_i2c_read_data();
302	envctrl_i2c_stop();
303
304	return readb(i2c + PCF8584_DATA);
305}
306
307/* Function Description: Read gpio device.
308 * Return : Data at address.
309 */
310static unsigned char envctrl_i2c_read_8574(unsigned char addr)
311{
312	unsigned char rd;
313
314	envctrl_i2c_read_addr(addr);
315
316	/* Do a single byte read and send stop. */
317	rd = envctrl_i2c_read_data();
318	envctrl_i2c_stop();
319	return rd;
320}
321
322/* Function Description: Decode data read from an adc device using firmware
323 *                       table.
324 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
325 */
326static int envctrl_i2c_data_translate(unsigned char data, int translate_type,
327				      int scale, char *tbl, char *bufdata)
328{
329	int len = 0;
330
331	switch (translate_type) {
332	case ENVCTRL_TRANSLATE_NO:
333		/* No decode necessary. */
334		len = 1;
335		bufdata[0] = data;
336		break;
337
338	case ENVCTRL_TRANSLATE_FULL:
339		/* Decode this way: data = table[data]. */
340		len = 1;
341		bufdata[0] = tbl[data];
342		break;
343
344	case ENVCTRL_TRANSLATE_SCALE:
345		/* Decode this way: data = table[data]/scale */
346		sprintf(bufdata,"%d ", (tbl[data] * 10) / (scale));
347		len = strlen(bufdata);
348		bufdata[len - 1] = bufdata[len - 2];
349		bufdata[len - 2] = '.';
350		break;
351
352	default:
353		break;
354	}
355
356	return len;
357}
358
359/* Function Description: Read cpu-related data such as cpu temperature, voltage.
360 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
361 */
362static int envctrl_read_cpu_info(int cpu, struct i2c_child_t *pchild,
363				 char mon_type, unsigned char *bufdata)
364{
365	unsigned char data;
366	int i, j = -1;
367	char *tbl;
368
369	/* Find the right monitor type and channel. */
370	for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
371		if (pchild->mon_type[i] == mon_type) {
372			if (++j == cpu) {
373				break;
374			}
375		}
376	}
377
378	if (j != cpu)
379		return 0;
380
381        /* Read data from address and port. */
382	data = envctrl_i2c_read_8591((unsigned char)pchild->addr,
383				     (unsigned char)pchild->chnl_array[i].chnl_no);
384
385	/* Find decoding table. */
386	tbl = pchild->tables + pchild->tblprop_array[i].offset;
387
388	return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type,
389					  pchild->tblprop_array[i].scale,
390					  tbl, bufdata);
391}
392
393/* Function Description: Read noncpu-related data such as motherboard
394 *                       temperature.
395 * Return: Number of read bytes. Data is stored in bufdata in ascii format.
396 */
397static int envctrl_read_noncpu_info(struct i2c_child_t *pchild,
398				    char mon_type, unsigned char *bufdata)
399{
400	unsigned char data;
401	int i;
402	char *tbl = NULL;
403
404	for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
405		if (pchild->mon_type[i] == mon_type)
406			break;
407	}
408
409	if (i >= PCF8584_MAX_CHANNELS)
410		return 0;
411
412        /* Read data from address and port. */
413	data = envctrl_i2c_read_8591((unsigned char)pchild->addr,
414				     (unsigned char)pchild->chnl_array[i].chnl_no);
415
416	/* Find decoding table. */
417	tbl = pchild->tables + pchild->tblprop_array[i].offset;
418
419	return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type,
420					  pchild->tblprop_array[i].scale,
421					  tbl, bufdata);
422}
423
424/* Function Description: Read fan status.
425 * Return : Always 1 byte. Status stored in bufdata.
426 */
427static int envctrl_i2c_fan_status(struct i2c_child_t *pchild,
428				  unsigned char data,
429				  char *bufdata)
430{
431	unsigned char tmp, ret = 0;
432	int i, j = 0;
433
434	tmp = data & pchild->fan_mask;
435
436	if (tmp == pchild->fan_mask) {
437		/* All bits are on. All fans are functioning. */
438		ret = ENVCTRL_ALL_FANS_GOOD;
439	} else if (tmp == 0) {
440		/* No bits are on. No fans are functioning. */
441		ret = ENVCTRL_ALL_FANS_BAD;
442	} else {
443		/* Go through all channels, mark 'on' the matched bits.
444		 * Notice that fan_mask may have discontiguous bits but
445		 * return mask are always contiguous. For example if we
446		 * monitor 4 fans at channels 0,1,2,4, the return mask
447		 * should be 00010000 if only fan at channel 4 is working.
448		 */
449		for (i = 0; i < PCF8584_MAX_CHANNELS;i++) {
450			if (pchild->fan_mask & chnls_mask[i]) {
451				if (!(chnls_mask[i] & tmp))
452					ret |= chnls_mask[j];
453
454				j++;
455			}
456		}
457	}
458
459	bufdata[0] = ret;
460	return 1;
461}
462
463/* Function Description: Read global addressing line.
464 * Return : Always 1 byte. Status stored in bufdata.
465 */
466static int envctrl_i2c_globaladdr(struct i2c_child_t *pchild,
467				  unsigned char data,
468				  char *bufdata)
469{
470	/* Translatation table is not necessary, as global
471	 * addr is the integer value of the GA# bits.
472	 *
473	 * NOTE: MSB is documented as zero, but I see it as '1' always....
474	 *
475	 * -----------------------------------------------
476	 * | 0 | FAL | DEG | GA4 | GA3 | GA2 | GA1 | GA0 |
477	 * -----------------------------------------------
478	 * GA0 - GA4	integer value of Global Address (backplane slot#)
479	 * DEG			0 = cPCI Power supply output is starting to degrade
480	 * 				1 = cPCI Power supply output is OK
481	 * FAL			0 = cPCI Power supply has failed
482	 * 				1 = cPCI Power supply output is OK
483	 */
484	bufdata[0] = (data & ENVCTRL_GLOBALADDR_ADDR_MASK);
485	return 1;
486}
487
488/* Function Description: Read standard voltage and power supply status.
489 * Return : Always 1 byte. Status stored in bufdata.
490 */
491static unsigned char envctrl_i2c_voltage_status(struct i2c_child_t *pchild,
492						unsigned char data,
493						char *bufdata)
494{
495	unsigned char tmp, ret = 0;
496	int i, j = 0;
497
498	tmp = data & pchild->voltage_mask;
499
500	/* Two channels are used to monitor voltage and power supply. */
501	if (tmp == pchild->voltage_mask) {
502		/* All bits are on. Voltage and power supply are okay. */
503		ret = ENVCTRL_VOLTAGE_POWERSUPPLY_GOOD;
504	} else if (tmp == 0) {
505		/* All bits are off. Voltage and power supply are bad */
506		ret = ENVCTRL_VOLTAGE_POWERSUPPLY_BAD;
507	} else {
508		/* Either voltage or power supply has problem. */
509		for (i = 0; i < PCF8584_MAX_CHANNELS; i++) {
510			if (pchild->voltage_mask & chnls_mask[i]) {
511				j++;
512
513				/* Break out when there is a mismatch. */
514				if (!(chnls_mask[i] & tmp))
515					break;
516			}
517		}
518
519		/* Make a wish that hardware will always use the
520		 * first channel for voltage and the second for
521		 * power supply.
522		 */
523		if (j == 1)
524			ret = ENVCTRL_VOLTAGE_BAD;
525		else
526			ret = ENVCTRL_POWERSUPPLY_BAD;
527	}
528
529	bufdata[0] = ret;
530	return 1;
531}
532
533/* Function Description: Read a byte from /dev/envctrl. Mapped to user read().
534 * Return: Number of read bytes. 0 for error.
535 */
536static ssize_t
537envctrl_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
538{
539	struct i2c_child_t *pchild;
540	unsigned char data[10];
541	int ret = 0;
542
543	/* Get the type of read as decided in ioctl() call.
544	 * Find the appropriate i2c child.
545	 * Get the data and put back to the user buffer.
546	 */
547
548	switch ((int)(long)file->private_data) {
549	case ENVCTRL_RD_WARNING_TEMPERATURE:
550		if (warning_temperature == 0)
551			return 0;
552
553		data[0] = (unsigned char)(warning_temperature);
554		ret = 1;
555		if (copy_to_user(buf, data, ret))
556			ret = -EFAULT;
557		break;
558
559	case ENVCTRL_RD_SHUTDOWN_TEMPERATURE:
560		if (shutdown_temperature == 0)
561			return 0;
562
563		data[0] = (unsigned char)(shutdown_temperature);
564		ret = 1;
565		if (copy_to_user(buf, data, ret))
566			ret = -EFAULT;
567		break;
568
569	case ENVCTRL_RD_MTHRBD_TEMPERATURE:
570		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_MTHRBDTEMP_MON)))
571			return 0;
572		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_MTHRBDTEMP_MON, data);
573		if (copy_to_user(buf, data, ret))
574			ret = -EFAULT;
575		break;
576
577	case ENVCTRL_RD_CPU_TEMPERATURE:
578		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON)))
579			return 0;
580		ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUTEMP_MON, data);
581
582		/* Reset cpu to the default cpu0. */
583		if (copy_to_user(buf, data, ret))
584			ret = -EFAULT;
585		break;
586
587	case ENVCTRL_RD_CPU_VOLTAGE:
588		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUVOLTAGE_MON)))
589			return 0;
590		ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUVOLTAGE_MON, data);
591
592		/* Reset cpu to the default cpu0. */
593		if (copy_to_user(buf, data, ret))
594			ret = -EFAULT;
595		break;
596
597	case ENVCTRL_RD_SCSI_TEMPERATURE:
598		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_SCSITEMP_MON)))
599			return 0;
600		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_SCSITEMP_MON, data);
601		if (copy_to_user(buf, data, ret))
602			ret = -EFAULT;
603		break;
604
605	case ENVCTRL_RD_ETHERNET_TEMPERATURE:
606		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_ETHERTEMP_MON)))
607			return 0;
608		ret = envctrl_read_noncpu_info(pchild, ENVCTRL_ETHERTEMP_MON, data);
609		if (copy_to_user(buf, data, ret))
610			ret = -EFAULT;
611		break;
612
613	case ENVCTRL_RD_FAN_STATUS:
614		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_FANSTAT_MON)))
615			return 0;
616		data[0] = envctrl_i2c_read_8574(pchild->addr);
617		ret = envctrl_i2c_fan_status(pchild,data[0], data);
618		if (copy_to_user(buf, data, ret))
619			ret = -EFAULT;
620		break;
621
622	case ENVCTRL_RD_GLOBALADDRESS:
623		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_GLOBALADDR_MON)))
624			return 0;
625		data[0] = envctrl_i2c_read_8574(pchild->addr);
626		ret = envctrl_i2c_globaladdr(pchild, data[0], data);
627		if (copy_to_user(buf, data, ret))
628			ret = -EFAULT;
629		break;
630
631	case ENVCTRL_RD_VOLTAGE_STATUS:
632		if (!(pchild = envctrl_get_i2c_child(ENVCTRL_VOLTAGESTAT_MON)))
633			/* If voltage monitor not present, check for CPCI equivalent */
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_voltage_status(pchild, data[0], data);
638		if (copy_to_user(buf, data, ret))
639			ret = -EFAULT;
640		break;
641
642	default:
643		break;
644
645	}
646
647	return ret;
648}
649
650/* Function Description: Command what to read.  Mapped to user ioctl().
651 * Return: Gives 0 for implemented commands, -EINVAL otherwise.
652 */
653static long
654envctrl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
655{
656	char __user *infobuf;
657
658	switch (cmd) {
659	case ENVCTRL_RD_WARNING_TEMPERATURE:
660	case ENVCTRL_RD_SHUTDOWN_TEMPERATURE:
661	case ENVCTRL_RD_MTHRBD_TEMPERATURE:
662	case ENVCTRL_RD_FAN_STATUS:
663	case ENVCTRL_RD_VOLTAGE_STATUS:
664	case ENVCTRL_RD_ETHERNET_TEMPERATURE:
665	case ENVCTRL_RD_SCSI_TEMPERATURE:
666	case ENVCTRL_RD_GLOBALADDRESS:
667		file->private_data = (void *)(long)cmd;
668		break;
669
670	case ENVCTRL_RD_CPU_TEMPERATURE:
671	case ENVCTRL_RD_CPU_VOLTAGE:
672		/* Check to see if application passes in any cpu number,
673		 * the default is cpu0.
674		 */
675		infobuf = (char __user *) arg;
676		if (infobuf == NULL) {
677			read_cpu = 0;
678		}else {
679			get_user(read_cpu, infobuf);
680		}
681
682		/* Save the command for use when reading. */
683		file->private_data = (void *)(long)cmd;
684		break;
685
686	default:
687		return -EINVAL;
688	}
689
690	return 0;
691}
692
693/* Function Description: open device. Mapped to user open().
694 * Return: Always 0.
695 */
696static int
697envctrl_open(struct inode *inode, struct file *file)
698{
699	file->private_data = NULL;
700	return 0;
701}
702
703/* Function Description: Open device. Mapped to user close().
704 * Return: Always 0.
705 */
706static int
707envctrl_release(struct inode *inode, struct file *file)
708{
709	return 0;
710}
711
712static const struct file_operations envctrl_fops = {
713	.owner =		THIS_MODULE,
714	.read =			envctrl_read,
715	.unlocked_ioctl =	envctrl_ioctl,
716	.compat_ioctl =		compat_ptr_ioctl,
717	.open =			envctrl_open,
718	.release =		envctrl_release,
719	.llseek =		noop_llseek,
720};
721
722static struct miscdevice envctrl_dev = {
723	ENVCTRL_MINOR,
724	"envctrl",
725	&envctrl_fops
726};
727
728/* Function Description: Set monitor type based on firmware description.
729 * Return: None.
730 */
731static void envctrl_set_mon(struct i2c_child_t *pchild,
732			    const char *chnl_desc,
733			    int chnl_no)
734{
735	/* Firmware only has temperature type.  It does not distinguish
736	 * different kinds of temperatures.  We use channel description
737	 * to disinguish them.
738	 */
739	if (!(strcmp(chnl_desc,"temp,cpu")) ||
740	    !(strcmp(chnl_desc,"temp,cpu0")) ||
741	    !(strcmp(chnl_desc,"temp,cpu1")) ||
742	    !(strcmp(chnl_desc,"temp,cpu2")) ||
743	    !(strcmp(chnl_desc,"temp,cpu3")))
744		pchild->mon_type[chnl_no] = ENVCTRL_CPUTEMP_MON;
745
746	if (!(strcmp(chnl_desc,"vddcore,cpu0")) ||
747	    !(strcmp(chnl_desc,"vddcore,cpu1")) ||
748	    !(strcmp(chnl_desc,"vddcore,cpu2")) ||
749	    !(strcmp(chnl_desc,"vddcore,cpu3")))
750		pchild->mon_type[chnl_no] = ENVCTRL_CPUVOLTAGE_MON;
751
752	if (!(strcmp(chnl_desc,"temp,motherboard")))
753		pchild->mon_type[chnl_no] = ENVCTRL_MTHRBDTEMP_MON;
754
755	if (!(strcmp(chnl_desc,"temp,scsi")))
756		pchild->mon_type[chnl_no] = ENVCTRL_SCSITEMP_MON;
757
758	if (!(strcmp(chnl_desc,"temp,ethernet")))
759		pchild->mon_type[chnl_no] = ENVCTRL_ETHERTEMP_MON;
760}
761
762/* Function Description: Initialize monitor channel with channel desc,
763 *                       decoding tables, monitor type, optional properties.
764 * Return: None.
765 */
766static void envctrl_init_adc(struct i2c_child_t *pchild, struct device_node *dp)
767{
768	int i = 0, len;
769	const char *pos;
770	const unsigned int *pval;
771
772	/* Firmware describe channels into a stream separated by a '\0'. */
773	pos = of_get_property(dp, "channels-description", &len);
774
775	while (len > 0) {
776		int l = strlen(pos) + 1;
777		envctrl_set_mon(pchild, pos, i++);
778		len -= l;
779		pos += l;
780	}
781
782	/* Get optional properties. */
783	pval = of_get_property(dp, "warning-temp", NULL);
784	if (pval)
785		warning_temperature = *pval;
786
787	pval = of_get_property(dp, "shutdown-temp", NULL);
788	if (pval)
789		shutdown_temperature = *pval;
790}
791
792/* Function Description: Initialize child device monitoring fan status.
793 * Return: None.
794 */
795static void envctrl_init_fanstat(struct i2c_child_t *pchild)
796{
797	int i;
798
799	/* Go through all channels and set up the mask. */
800	for (i = 0; i < pchild->total_chnls; i++)
801		pchild->fan_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];
802
803	/* We only need to know if this child has fan status monitored.
804	 * We don't care which channels since we have the mask already.
805	 */
806	pchild->mon_type[0] = ENVCTRL_FANSTAT_MON;
807}
808
809/* Function Description: Initialize child device for global addressing line.
810 * Return: None.
811 */
812static void envctrl_init_globaladdr(struct i2c_child_t *pchild)
813{
814	int i;
815
816	/* Voltage/PowerSupply monitoring is piggybacked
817	 * with Global Address on CompactPCI.  See comments
818	 * within envctrl_i2c_globaladdr for bit assignments.
819	 *
820	 * The mask is created here by assigning mask bits to each
821	 * bit position that represents PCF8584_VOLTAGE_TYPE data.
822	 * Channel numbers are not consecutive within the globaladdr
823	 * node (why?), so we use the actual counter value as chnls_mask
824	 * index instead of the chnl_array[x].chnl_no value.
825	 *
826	 * NOTE: This loop could be replaced with a constant representing
827	 * a mask of bits 5&6 (ENVCTRL_GLOBALADDR_PSTAT_MASK).
828	 */
829	for (i = 0; i < pchild->total_chnls; i++) {
830		if (PCF8584_VOLTAGE_TYPE == pchild->chnl_array[i].type) {
831			pchild->voltage_mask |= chnls_mask[i];
832		}
833	}
834
835	/* We only need to know if this child has global addressing
836	 * line monitored.  We don't care which channels since we know
837	 * the mask already (ENVCTRL_GLOBALADDR_ADDR_MASK).
838	 */
839	pchild->mon_type[0] = ENVCTRL_GLOBALADDR_MON;
840}
841
842/* Initialize child device monitoring voltage status. */
843static void envctrl_init_voltage_status(struct i2c_child_t *pchild)
844{
845	int i;
846
847	/* Go through all channels and set up the mask. */
848	for (i = 0; i < pchild->total_chnls; i++)
849		pchild->voltage_mask |= chnls_mask[(pchild->chnl_array[i]).chnl_no];
850
851	/* We only need to know if this child has voltage status monitored.
852	 * We don't care which channels since we have the mask already.
853	 */
854	pchild->mon_type[0] = ENVCTRL_VOLTAGESTAT_MON;
855}
856
857/* Function Description: Initialize i2c child device.
858 * Return: None.
859 */
860static void envctrl_init_i2c_child(struct device_node *dp,
861				   struct i2c_child_t *pchild)
862{
863	int len, i, tbls_size = 0;
864	const void *pval;
865
866	/* Get device address. */
867	pval = of_get_property(dp, "reg", &len);
868	memcpy(&pchild->addr, pval, len);
869
870	/* Get tables property.  Read firmware temperature tables. */
871	pval = of_get_property(dp, "translation", &len);
872	if (pval && len > 0) {
873		memcpy(pchild->tblprop_array, pval, len);
874                pchild->total_tbls = len / sizeof(struct pcf8584_tblprop);
875		for (i = 0; i < pchild->total_tbls; i++) {
876			if ((pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset) > tbls_size) {
877				tbls_size = pchild->tblprop_array[i].size + pchild->tblprop_array[i].offset;
878			}
879		}
880
881                pchild->tables = kmalloc(tbls_size, GFP_KERNEL);
882		if (pchild->tables == NULL){
883			printk(KERN_ERR PFX "Failed to allocate table.\n");
884			return;
885		}
886		pval = of_get_property(dp, "tables", &len);
887                if (!pval || len <= 0) {
888			printk(KERN_ERR PFX "Failed to get table.\n");
889			return;
890		}
891		memcpy(pchild->tables, pval, len);
892	}
893
894	/* SPARCengine ASM Reference Manual (ref. SMI doc 805-7581-04)
895	 * sections 2.5, 3.5, 4.5 state node 0x70 for CP1400/1500 is
896	 * "For Factory Use Only."
897	 *
898	 * We ignore the node on these platforms by assigning the
899	 * 'NULL' monitor type.
900	 */
901	if (ENVCTRL_CPCI_IGNORED_NODE == pchild->addr) {
902		struct device_node *root_node;
903		int len;
904
905		root_node = of_find_node_by_path("/");
906		if (of_node_name_eq(root_node, "SUNW,UltraSPARC-IIi-cEngine")) {
907			for (len = 0; len < PCF8584_MAX_CHANNELS; ++len) {
908				pchild->mon_type[len] = ENVCTRL_NOMON;
909			}
910			of_node_put(root_node);
911			return;
912		}
913		of_node_put(root_node);
914	}
915
916	/* Get the monitor channels. */
917	pval = of_get_property(dp, "channels-in-use", &len);
918	memcpy(pchild->chnl_array, pval, len);
919	pchild->total_chnls = len / sizeof(struct pcf8584_channel);
920
921	for (i = 0; i < pchild->total_chnls; i++) {
922		switch (pchild->chnl_array[i].type) {
923		case PCF8584_TEMP_TYPE:
924			envctrl_init_adc(pchild, dp);
925			break;
926
927		case PCF8584_GLOBALADDR_TYPE:
928			envctrl_init_globaladdr(pchild);
929			i = pchild->total_chnls;
930			break;
931
932		case PCF8584_FANSTAT_TYPE:
933			envctrl_init_fanstat(pchild);
934			i = pchild->total_chnls;
935			break;
936
937		case PCF8584_VOLTAGE_TYPE:
938			if (pchild->i2ctype == I2C_ADC) {
939				envctrl_init_adc(pchild,dp);
940			} else {
941				envctrl_init_voltage_status(pchild);
942			}
943			i = pchild->total_chnls;
944			break;
945
946		default:
947			break;
948		}
949	}
950}
951
952/* Function Description: Search the child device list for a device.
953 * Return : The i2c child if found. NULL otherwise.
954 */
955static struct i2c_child_t *envctrl_get_i2c_child(unsigned char mon_type)
956{
957	int i, j;
958
959	for (i = 0; i < ENVCTRL_MAX_CPU*2; i++) {
960		for (j = 0; j < PCF8584_MAX_CHANNELS; j++) {
961			if (i2c_childlist[i].mon_type[j] == mon_type) {
962				return (struct i2c_child_t *)(&(i2c_childlist[i]));
963			}
964		}
965	}
966	return NULL;
967}
968
969static void envctrl_do_shutdown(void)
970{
971	static int inprog = 0;
972
973	if (inprog != 0)
974		return;
975
976	inprog = 1;
977	printk(KERN_CRIT "kenvctrld: WARNING: Shutting down the system now.\n");
978	orderly_poweroff(true);
979}
980
981static struct task_struct *kenvctrld_task;
982
983static int kenvctrld(void *__unused)
984{
985	int poll_interval;
986	int whichcpu;
987	char tempbuf[10];
988	struct i2c_child_t *cputemp;
989
990	if (NULL == (cputemp = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON))) {
991		printk(KERN_ERR  PFX
992		       "kenvctrld unable to monitor CPU temp-- exiting\n");
993		return -ENODEV;
994	}
995
996	poll_interval = 5000; /* TODO env_mon_interval */
997
998	printk(KERN_INFO PFX "%s starting...\n", current->comm);
999	for (;;) {
1000		msleep_interruptible(poll_interval);
1001
1002		if (kthread_should_stop())
1003			break;
1004
1005		for (whichcpu = 0; whichcpu < ENVCTRL_MAX_CPU; ++whichcpu) {
1006			if (0 < envctrl_read_cpu_info(whichcpu, cputemp,
1007						      ENVCTRL_CPUTEMP_MON,
1008						      tempbuf)) {
1009				if (tempbuf[0] >= shutdown_temperature) {
1010					printk(KERN_CRIT
1011						"%s: WARNING: CPU%i temperature %i C meets or exceeds "\
1012						"shutdown threshold %i C\n",
1013						current->comm, whichcpu,
1014						tempbuf[0], shutdown_temperature);
1015					envctrl_do_shutdown();
1016				}
1017			}
1018		}
1019	}
1020	printk(KERN_INFO PFX "%s exiting...\n", current->comm);
1021	return 0;
1022}
1023
1024static int envctrl_probe(struct platform_device *op)
1025{
1026	struct device_node *dp;
1027	int index, err;
1028
1029	if (i2c)
1030		return -EINVAL;
1031
1032	i2c = of_ioremap(&op->resource[0], 0, 0x2, DRIVER_NAME);
1033	if (!i2c)
1034		return -ENOMEM;
1035
1036	index = 0;
1037	dp = op->dev.of_node->child;
1038	while (dp) {
1039		if (of_node_name_eq(dp, "gpio")) {
1040			i2c_childlist[index].i2ctype = I2C_GPIO;
1041			envctrl_init_i2c_child(dp, &(i2c_childlist[index++]));
1042		} else if (of_node_name_eq(dp, "adc")) {
1043			i2c_childlist[index].i2ctype = I2C_ADC;
1044			envctrl_init_i2c_child(dp, &(i2c_childlist[index++]));
1045		}
1046
1047		dp = dp->sibling;
1048	}
1049
1050	/* Set device address. */
1051	writeb(CONTROL_PIN, i2c + PCF8584_CSR);
1052	writeb(PCF8584_ADDRESS, i2c + PCF8584_DATA);
1053
1054	/* Set system clock and SCL frequencies. */
1055	writeb(CONTROL_PIN | CONTROL_ES1, i2c + PCF8584_CSR);
1056	writeb(CLK_4_43 | BUS_CLK_90, i2c + PCF8584_DATA);
1057
1058	/* Enable serial interface. */
1059	writeb(CONTROL_PIN | CONTROL_ES0 | CONTROL_ACK, i2c + PCF8584_CSR);
1060	udelay(200);
1061
1062	/* Register the device as a minor miscellaneous device. */
1063	err = misc_register(&envctrl_dev);
1064	if (err) {
1065		printk(KERN_ERR PFX "Unable to get misc minor %d\n",
1066		       envctrl_dev.minor);
1067		goto out_iounmap;
1068	}
1069
1070	/* Note above traversal routine post-incremented 'i' to accommodate
1071	 * a next child device, so we decrement before reverse-traversal of
1072	 * child devices.
1073	 */
1074	printk(KERN_INFO PFX "Initialized ");
1075	for (--index; index >= 0; --index) {
1076		printk("[%s 0x%lx]%s",
1077			(I2C_ADC == i2c_childlist[index].i2ctype) ? "adc" :
1078			((I2C_GPIO == i2c_childlist[index].i2ctype) ? "gpio" : "unknown"),
1079			i2c_childlist[index].addr, (0 == index) ? "\n" : " ");
1080	}
1081
1082	kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
1083	if (IS_ERR(kenvctrld_task)) {
1084		err = PTR_ERR(kenvctrld_task);
1085		goto out_deregister;
1086	}
1087
1088	return 0;
1089
1090out_deregister:
1091	misc_deregister(&envctrl_dev);
1092out_iounmap:
1093	of_iounmap(&op->resource[0], i2c, 0x2);
1094	for (index = 0; index < ENVCTRL_MAX_CPU * 2; index++)
1095		kfree(i2c_childlist[index].tables);
1096
1097	return err;
1098}
1099
1100static void envctrl_remove(struct platform_device *op)
1101{
1102	int index;
1103
1104	kthread_stop(kenvctrld_task);
1105
1106	of_iounmap(&op->resource[0], i2c, 0x2);
1107	misc_deregister(&envctrl_dev);
1108
1109	for (index = 0; index < ENVCTRL_MAX_CPU * 2; index++)
1110		kfree(i2c_childlist[index].tables);
1111}
1112
1113static const struct of_device_id envctrl_match[] = {
1114	{
1115		.name = "i2c",
1116		.compatible = "i2cpcf,8584",
1117	},
1118	{},
1119};
1120MODULE_DEVICE_TABLE(of, envctrl_match);
1121
1122static struct platform_driver envctrl_driver = {
1123	.driver = {
1124		.name = DRIVER_NAME,
1125		.of_match_table = envctrl_match,
1126	},
1127	.probe		= envctrl_probe,
1128	.remove_new	= envctrl_remove,
1129};
1130
1131module_platform_driver(envctrl_driver);
1132
1133MODULE_LICENSE("GPL");
1134