xref: /linux/drivers/i2c/busses/i2c-ali15x3.c (revision d67b569f5f620c0fb95d5212642746b7ba9d29e4)
1 /*
2     ali15x3.c - Part of lm_sensors, Linux kernel modules for hardware
3               monitoring
4     Copyright (c) 1999  Frodo Looijaard <frodol@dds.nl> and
5     Philip Edelbrock <phil@netroedge.com> and
6     Mark D. Studebaker <mdsxyz123@yahoo.com>
7 
8     This program is free software; you can redistribute it and/or modify
9     it under the terms of the GNU General Public License as published by
10     the Free Software Foundation; either version 2 of the License, or
11     (at your option) any later version.
12 
13     This program is distributed in the hope that it will be useful,
14     but WITHOUT ANY WARRANTY; without even the implied warranty of
15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16     GNU General Public License for more details.
17 
18     You should have received a copy of the GNU General Public License
19     along with this program; if not, write to the Free Software
20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22 
23 /*
24     This is the driver for the SMB Host controller on
25     Acer Labs Inc. (ALI) M1541 and M1543C South Bridges.
26 
27     The M1543C is a South bridge for desktop systems.
28     The M1533 is a South bridge for portable systems.
29     They are part of the following ALI chipsets:
30        "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge
31        with AGP and 100MHz CPU Front Side bus
32        "Aladdin V": Includes the M1541 Socket 7 North bridge
33        with AGP and 100MHz CPU Front Side bus
34        "Aladdin IV": Includes the M1541 Socket 7 North bridge
35        with host bus up to 83.3 MHz.
36     For an overview of these chips see http://www.acerlabs.com
37 
38     The M1533/M1543C devices appear as FOUR separate devices
39     on the PCI bus. An output of lspci will show something similar
40     to the following:
41 
42 	00:02.0 USB Controller: Acer Laboratories Inc. M5237
43 	00:03.0 Bridge: Acer Laboratories Inc. M7101
44 	00:07.0 ISA bridge: Acer Laboratories Inc. M1533
45 	00:0f.0 IDE interface: Acer Laboratories Inc. M5229
46 
47     The SMB controller is part of the 7101 device, which is an
48     ACPI-compliant Power Management Unit (PMU).
49 
50     The whole 7101 device has to be enabled for the SMB to work.
51     You can't just enable the SMB alone.
52     The SMB and the ACPI have separate I/O spaces.
53     We make sure that the SMB is enabled. We leave the ACPI alone.
54 
55     This driver controls the SMB Host only.
56     The SMB Slave controller on the M15X3 is not enabled.
57 
58     This driver does not use interrupts.
59 */
60 
61 /* Note: we assume there can only be one ALI15X3, with one SMBus interface */
62 
63 #include <linux/module.h>
64 #include <linux/pci.h>
65 #include <linux/kernel.h>
66 #include <linux/stddef.h>
67 #include <linux/sched.h>
68 #include <linux/ioport.h>
69 #include <linux/delay.h>
70 #include <linux/i2c.h>
71 #include <linux/init.h>
72 #include <asm/io.h>
73 
74 /* ALI15X3 SMBus address offsets */
75 #define SMBHSTSTS	(0 + ali15x3_smba)
76 #define SMBHSTCNT	(1 + ali15x3_smba)
77 #define SMBHSTSTART	(2 + ali15x3_smba)
78 #define SMBHSTCMD	(7 + ali15x3_smba)
79 #define SMBHSTADD	(3 + ali15x3_smba)
80 #define SMBHSTDAT0	(4 + ali15x3_smba)
81 #define SMBHSTDAT1	(5 + ali15x3_smba)
82 #define SMBBLKDAT	(6 + ali15x3_smba)
83 
84 /* PCI Address Constants */
85 #define SMBCOM		0x004
86 #define SMBBA		0x014
87 #define SMBATPC		0x05B	/* used to unlock xxxBA registers */
88 #define SMBHSTCFG	0x0E0
89 #define SMBSLVC		0x0E1
90 #define SMBCLK		0x0E2
91 #define SMBREV		0x008
92 
93 /* Other settings */
94 #define MAX_TIMEOUT		200	/* times 1/100 sec */
95 #define ALI15X3_SMB_IOSIZE	32
96 
97 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
98    We don't use these here. If the bases aren't set to some value we
99    tell user to upgrade BIOS and we fail.
100 */
101 #define ALI15X3_SMB_DEFAULTBASE	0xE800
102 
103 /* ALI15X3 address lock bits */
104 #define ALI15X3_LOCK		0x06
105 
106 /* ALI15X3 command constants */
107 #define ALI15X3_ABORT		0x02
108 #define ALI15X3_T_OUT		0x04
109 #define ALI15X3_QUICK		0x00
110 #define ALI15X3_BYTE		0x10
111 #define ALI15X3_BYTE_DATA	0x20
112 #define ALI15X3_WORD_DATA	0x30
113 #define ALI15X3_BLOCK_DATA	0x40
114 #define ALI15X3_BLOCK_CLR	0x80
115 
116 /* ALI15X3 status register bits */
117 #define ALI15X3_STS_IDLE	0x04
118 #define ALI15X3_STS_BUSY	0x08
119 #define ALI15X3_STS_DONE	0x10
120 #define ALI15X3_STS_DEV		0x20	/* device error */
121 #define ALI15X3_STS_COLL	0x40	/* collision or no response */
122 #define ALI15X3_STS_TERM	0x80	/* terminated by abort */
123 #define ALI15X3_STS_ERR		0xE0	/* all the bad error bits */
124 
125 
126 /* If force_addr is set to anything different from 0, we forcibly enable
127    the device at the given address. */
128 static u16 force_addr = 0;
129 module_param(force_addr, ushort, 0);
130 MODULE_PARM_DESC(force_addr,
131 		 "Initialize the base address of the i2c controller");
132 
133 static unsigned short ali15x3_smba = 0;
134 
135 static int ali15x3_setup(struct pci_dev *ALI15X3_dev)
136 {
137 	u16 a;
138 	unsigned char temp;
139 
140 	/* Check the following things:
141 		- SMB I/O address is initialized
142 		- Device is enabled
143 		- We can use the addresses
144 	*/
145 
146 	/* Unlock the register.
147 	   The data sheet says that the address registers are read-only
148 	   if the lock bits are 1, but in fact the address registers
149 	   are zero unless you clear the lock bits.
150 	*/
151 	pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
152 	if (temp & ALI15X3_LOCK) {
153 		temp &= ~ALI15X3_LOCK;
154 		pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
155 	}
156 
157 	/* Determine the address of the SMBus area */
158 	pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
159 	ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
160 	if (ali15x3_smba == 0 && force_addr == 0) {
161 		dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
162 			"- upgrade BIOS or use force_addr=0xaddr\n");
163 		return -ENODEV;
164 	}
165 
166 	if(force_addr)
167 		ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
168 
169 	if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE, "ali15x3-smb")) {
170 		dev_err(&ALI15X3_dev->dev,
171 			"ALI15X3_smb region 0x%x already in use!\n",
172 			ali15x3_smba);
173 		return -ENODEV;
174 	}
175 
176 	if(force_addr) {
177 		dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
178 			ali15x3_smba);
179 		if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
180 								SMBBA,
181 								ali15x3_smba))
182 			goto error;
183 		if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
184 								SMBBA, &a))
185 			goto error;
186 		if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
187 			/* make sure it works */
188 			dev_err(&ALI15X3_dev->dev,
189 				"force address failed - not supported?\n");
190 			goto error;
191 		}
192 	}
193 	/* check if whole device is enabled */
194 	pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
195 	if ((temp & 1) == 0) {
196 		dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
197 		pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
198 	}
199 
200 	/* Is SMB Host controller enabled? */
201 	pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
202 	if ((temp & 1) == 0) {
203 		dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
204 		pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
205 	}
206 
207 	/* set SMB clock to 74KHz as recommended in data sheet */
208 	pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
209 
210 	/*
211 	  The interrupt routing for SMB is set up in register 0x77 in the
212 	  1533 ISA Bridge device, NOT in the 7101 device.
213 	  Don't bother with finding the 1533 device and reading the register.
214 	if ((....... & 0x0F) == 1)
215 		dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
216 	*/
217 	pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
218 	dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
219 	dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
220 
221 	return 0;
222 error:
223 	release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
224 	return -ENODEV;
225 }
226 
227 /* Another internally used function */
228 static int ali15x3_transaction(struct i2c_adapter *adap)
229 {
230 	int temp;
231 	int result = 0;
232 	int timeout = 0;
233 
234 	dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
235 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
236 		inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
237 		inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
238 
239 	/* get status */
240 	temp = inb_p(SMBHSTSTS);
241 
242 	/* Make sure the SMBus host is ready to start transmitting */
243 	/* Check the busy bit first */
244 	if (temp & ALI15X3_STS_BUSY) {
245 	/*
246 	   If the host controller is still busy, it may have timed out in the
247 	   previous transaction, resulting in a "SMBus Timeout" Dev.
248 	   I've tried the following to reset a stuck busy bit.
249 		1. Reset the controller with an ABORT command.
250 		   (this doesn't seem to clear the controller if an external
251 		   device is hung)
252 		2. Reset the controller and the other SMBus devices with a
253 		   T_OUT command.  (this clears the host busy bit if an
254 		   external device is hung, but it comes back upon a new access
255 		   to a device)
256 		3. Disable and reenable the controller in SMBHSTCFG
257 	   Worst case, nothing seems to work except power reset.
258 	*/
259 	/* Abort - reset the host controller */
260 	/*
261 	   Try resetting entire SMB bus, including other devices -
262 	   This may not work either - it clears the BUSY bit but
263 	   then the BUSY bit may come back on when you try and use the chip again.
264 	   If that's the case you are stuck.
265 	*/
266 		dev_info(&adap->dev, "Resetting entire SMB Bus to "
267 			"clear busy condition (%02x)\n", temp);
268 		outb_p(ALI15X3_T_OUT, SMBHSTCNT);
269 		temp = inb_p(SMBHSTSTS);
270 	}
271 
272 	/* now check the error bits and the busy bit */
273 	if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
274 		/* do a clear-on-write */
275 		outb_p(0xFF, SMBHSTSTS);
276 		if ((temp = inb_p(SMBHSTSTS)) &
277 		    (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
278 			/* this is probably going to be correctable only by a power reset
279 			   as one of the bits now appears to be stuck */
280 			/* This may be a bus or device with electrical problems. */
281 			dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
282 				"controller or device on bus is probably hung\n",
283 				temp);
284 			return -1;
285 		}
286 	} else {
287 		/* check and clear done bit */
288 		if (temp & ALI15X3_STS_DONE) {
289 			outb_p(temp, SMBHSTSTS);
290 		}
291 	}
292 
293 	/* start the transaction by writing anything to the start register */
294 	outb_p(0xFF, SMBHSTSTART);
295 
296 	/* We will always wait for a fraction of a second! */
297 	timeout = 0;
298 	do {
299 		msleep(1);
300 		temp = inb_p(SMBHSTSTS);
301 	} while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
302 		 && (timeout++ < MAX_TIMEOUT));
303 
304 	/* If the SMBus is still busy, we give up */
305 	if (timeout >= MAX_TIMEOUT) {
306 		result = -1;
307 		dev_err(&adap->dev, "SMBus Timeout!\n");
308 	}
309 
310 	if (temp & ALI15X3_STS_TERM) {
311 		result = -1;
312 		dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
313 	}
314 
315 	/*
316 	  Unfortunately the ALI SMB controller maps "no response" and "bus
317 	  collision" into a single bit. No reponse is the usual case so don't
318 	  do a printk.
319 	  This means that bus collisions go unreported.
320 	*/
321 	if (temp & ALI15X3_STS_COLL) {
322 		result = -1;
323 		dev_dbg(&adap->dev,
324 			"Error: no response or bus collision ADD=%02x\n",
325 			inb_p(SMBHSTADD));
326 	}
327 
328 	/* haven't ever seen this */
329 	if (temp & ALI15X3_STS_DEV) {
330 		result = -1;
331 		dev_err(&adap->dev, "Error: device error\n");
332 	}
333 	dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
334 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
335 		inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
336 		inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
337 	return result;
338 }
339 
340 /* Return -1 on error. */
341 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
342 		   unsigned short flags, char read_write, u8 command,
343 		   int size, union i2c_smbus_data * data)
344 {
345 	int i, len;
346 	int temp;
347 	int timeout;
348 
349 	/* clear all the bits (clear-on-write) */
350 	outb_p(0xFF, SMBHSTSTS);
351 	/* make sure SMBus is idle */
352 	temp = inb_p(SMBHSTSTS);
353 	for (timeout = 0;
354 	     (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
355 	     timeout++) {
356 		msleep(1);
357 		temp = inb_p(SMBHSTSTS);
358 	}
359 	if (timeout >= MAX_TIMEOUT) {
360 		dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
361 	}
362 
363 	switch (size) {
364 	case I2C_SMBUS_PROC_CALL:
365 		dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
366 		return -1;
367 	case I2C_SMBUS_QUICK:
368 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
369 		       SMBHSTADD);
370 		size = ALI15X3_QUICK;
371 		break;
372 	case I2C_SMBUS_BYTE:
373 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
374 		       SMBHSTADD);
375 		if (read_write == I2C_SMBUS_WRITE)
376 			outb_p(command, SMBHSTCMD);
377 		size = ALI15X3_BYTE;
378 		break;
379 	case I2C_SMBUS_BYTE_DATA:
380 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
381 		       SMBHSTADD);
382 		outb_p(command, SMBHSTCMD);
383 		if (read_write == I2C_SMBUS_WRITE)
384 			outb_p(data->byte, SMBHSTDAT0);
385 		size = ALI15X3_BYTE_DATA;
386 		break;
387 	case I2C_SMBUS_WORD_DATA:
388 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
389 		       SMBHSTADD);
390 		outb_p(command, SMBHSTCMD);
391 		if (read_write == I2C_SMBUS_WRITE) {
392 			outb_p(data->word & 0xff, SMBHSTDAT0);
393 			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
394 		}
395 		size = ALI15X3_WORD_DATA;
396 		break;
397 	case I2C_SMBUS_BLOCK_DATA:
398 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
399 		       SMBHSTADD);
400 		outb_p(command, SMBHSTCMD);
401 		if (read_write == I2C_SMBUS_WRITE) {
402 			len = data->block[0];
403 			if (len < 0) {
404 				len = 0;
405 				data->block[0] = len;
406 			}
407 			if (len > 32) {
408 				len = 32;
409 				data->block[0] = len;
410 			}
411 			outb_p(len, SMBHSTDAT0);
412 			/* Reset SMBBLKDAT */
413 			outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
414 			for (i = 1; i <= len; i++)
415 				outb_p(data->block[i], SMBBLKDAT);
416 		}
417 		size = ALI15X3_BLOCK_DATA;
418 		break;
419 	}
420 
421 	outb_p(size, SMBHSTCNT);	/* output command */
422 
423 	if (ali15x3_transaction(adap))	/* Error in transaction */
424 		return -1;
425 
426 	if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
427 		return 0;
428 
429 
430 	switch (size) {
431 	case ALI15X3_BYTE:	/* Result put in SMBHSTDAT0 */
432 		data->byte = inb_p(SMBHSTDAT0);
433 		break;
434 	case ALI15X3_BYTE_DATA:
435 		data->byte = inb_p(SMBHSTDAT0);
436 		break;
437 	case ALI15X3_WORD_DATA:
438 		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
439 		break;
440 	case ALI15X3_BLOCK_DATA:
441 		len = inb_p(SMBHSTDAT0);
442 		if (len > 32)
443 			len = 32;
444 		data->block[0] = len;
445 		/* Reset SMBBLKDAT */
446 		outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
447 		for (i = 1; i <= data->block[0]; i++) {
448 			data->block[i] = inb_p(SMBBLKDAT);
449 			dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
450 				len, i, data->block[i]);
451 		}
452 		break;
453 	}
454 	return 0;
455 }
456 
457 static u32 ali15x3_func(struct i2c_adapter *adapter)
458 {
459 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
460 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
461 	    I2C_FUNC_SMBUS_BLOCK_DATA;
462 }
463 
464 static struct i2c_algorithm smbus_algorithm = {
465 	.name		= "Non-I2C SMBus adapter",
466 	.id		= I2C_ALGO_SMBUS,
467 	.smbus_xfer	= ali15x3_access,
468 	.functionality	= ali15x3_func,
469 };
470 
471 static struct i2c_adapter ali15x3_adapter = {
472 	.owner		= THIS_MODULE,
473 	.class          = I2C_CLASS_HWMON,
474 	.algo		= &smbus_algorithm,
475 	.name		= "unset",
476 };
477 
478 static struct pci_device_id ali15x3_ids[] = {
479 	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
480 	{ 0, }
481 };
482 
483 MODULE_DEVICE_TABLE (pci, ali15x3_ids);
484 
485 static int __devinit ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
486 {
487 	if (ali15x3_setup(dev)) {
488 		dev_err(&dev->dev,
489 			"ALI15X3 not detected, module not inserted.\n");
490 		return -ENODEV;
491 	}
492 
493 	/* set up the driverfs linkage to our parent device */
494 	ali15x3_adapter.dev.parent = &dev->dev;
495 
496 	snprintf(ali15x3_adapter.name, I2C_NAME_SIZE,
497 		"SMBus ALI15X3 adapter at %04x", ali15x3_smba);
498 	return i2c_add_adapter(&ali15x3_adapter);
499 }
500 
501 static void __devexit ali15x3_remove(struct pci_dev *dev)
502 {
503 	i2c_del_adapter(&ali15x3_adapter);
504 	release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
505 }
506 
507 static struct pci_driver ali15x3_driver = {
508 	.name		= "ali15x3_smbus",
509 	.id_table	= ali15x3_ids,
510 	.probe		= ali15x3_probe,
511 	.remove		= __devexit_p(ali15x3_remove),
512 };
513 
514 static int __init i2c_ali15x3_init(void)
515 {
516 	return pci_register_driver(&ali15x3_driver);
517 }
518 
519 static void __exit i2c_ali15x3_exit(void)
520 {
521 	pci_unregister_driver(&ali15x3_driver);
522 }
523 
524 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
525 		"Philip Edelbrock <phil@netroedge.com>, "
526 		"and Mark D. Studebaker <mdsxyz123@yahoo.com>");
527 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
528 MODULE_LICENSE("GPL");
529 
530 module_init(i2c_ali15x3_init);
531 module_exit(i2c_ali15x3_exit);
532