1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 Copyright (c) 1999 Frodo Looijaard <frodol@dds.nl> and
4 Philip Edelbrock <phil@netroedge.com> and
5 Mark D. Studebaker <mdsxyz123@yahoo.com>
6
7 */
8
9 /*
10 This is the driver for the SMB Host controller on
11 Acer Labs Inc. (ALI) M1541 and M1543C South Bridges.
12
13 The M1543C is a South bridge for desktop systems.
14 The M1533 is a South bridge for portable systems.
15 They are part of the following ALI chipsets:
16 "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge
17 with AGP and 100MHz CPU Front Side bus
18 "Aladdin V": Includes the M1541 Socket 7 North bridge
19 with AGP and 100MHz CPU Front Side bus
20 "Aladdin IV": Includes the M1541 Socket 7 North bridge
21 with host bus up to 83.3 MHz.
22 For an overview of these chips see http://www.acerlabs.com
23
24 The M1533/M1543C devices appear as FOUR separate devices
25 on the PCI bus. An output of lspci will show something similar
26 to the following:
27
28 00:02.0 USB Controller: Acer Laboratories Inc. M5237
29 00:03.0 Bridge: Acer Laboratories Inc. M7101
30 00:07.0 ISA bridge: Acer Laboratories Inc. M1533
31 00:0f.0 IDE interface: Acer Laboratories Inc. M5229
32
33 The SMB controller is part of the 7101 device, which is an
34 ACPI-compliant Power Management Unit (PMU).
35
36 The whole 7101 device has to be enabled for the SMB to work.
37 You can't just enable the SMB alone.
38 The SMB and the ACPI have separate I/O spaces.
39 We make sure that the SMB is enabled. We leave the ACPI alone.
40
41 This driver controls the SMB Host only.
42 The SMB Slave controller on the M15X3 is not enabled.
43
44 This driver does not use interrupts.
45 */
46
47 /* Note: we assume there can only be one ALI15X3, with one SMBus interface */
48
49 #include <linux/module.h>
50 #include <linux/pci.h>
51 #include <linux/kernel.h>
52 #include <linux/stddef.h>
53 #include <linux/ioport.h>
54 #include <linux/delay.h>
55 #include <linux/i2c.h>
56 #include <linux/acpi.h>
57 #include <linux/io.h>
58
59 /* ALI15X3 SMBus address offsets */
60 #define SMBHSTSTS (0 + ali15x3_smba)
61 #define SMBHSTCNT (1 + ali15x3_smba)
62 #define SMBHSTSTART (2 + ali15x3_smba)
63 #define SMBHSTCMD (7 + ali15x3_smba)
64 #define SMBHSTADD (3 + ali15x3_smba)
65 #define SMBHSTDAT0 (4 + ali15x3_smba)
66 #define SMBHSTDAT1 (5 + ali15x3_smba)
67 #define SMBBLKDAT (6 + ali15x3_smba)
68
69 /* PCI Address Constants */
70 #define SMBCOM 0x004
71 #define SMBBA 0x014
72 #define SMBATPC 0x05B /* used to unlock xxxBA registers */
73 #define SMBHSTCFG 0x0E0
74 #define SMBSLVC 0x0E1
75 #define SMBCLK 0x0E2
76 #define SMBREV 0x008
77
78 /* Other settings */
79 #define MAX_TIMEOUT 200 /* times 1/100 sec */
80 #define ALI15X3_SMB_IOSIZE 32
81
82 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
83 We don't use these here. If the bases aren't set to some value we
84 tell user to upgrade BIOS and we fail.
85 */
86 #define ALI15X3_SMB_DEFAULTBASE 0xE800
87
88 /* ALI15X3 address lock bits */
89 #define ALI15X3_LOCK 0x06
90
91 /* ALI15X3 command constants */
92 #define ALI15X3_ABORT 0x02
93 #define ALI15X3_T_OUT 0x04
94 #define ALI15X3_QUICK 0x00
95 #define ALI15X3_BYTE 0x10
96 #define ALI15X3_BYTE_DATA 0x20
97 #define ALI15X3_WORD_DATA 0x30
98 #define ALI15X3_BLOCK_DATA 0x40
99 #define ALI15X3_BLOCK_CLR 0x80
100
101 /* ALI15X3 status register bits */
102 #define ALI15X3_STS_IDLE 0x04
103 #define ALI15X3_STS_BUSY 0x08
104 #define ALI15X3_STS_DONE 0x10
105 #define ALI15X3_STS_DEV 0x20 /* device error */
106 #define ALI15X3_STS_COLL 0x40 /* collision or no response */
107 #define ALI15X3_STS_TERM 0x80 /* terminated by abort */
108 #define ALI15X3_STS_ERR 0xE0 /* all the bad error bits */
109
110
111 /* If force_addr is set to anything different from 0, we forcibly enable
112 the device at the given address. */
113 static u16 force_addr;
114 module_param_hw(force_addr, ushort, ioport, 0);
115 MODULE_PARM_DESC(force_addr,
116 "Initialize the base address of the i2c controller");
117
118 static struct pci_driver ali15x3_driver;
119 static unsigned short ali15x3_smba;
120
ali15x3_setup(struct pci_dev * ALI15X3_dev)121 static int ali15x3_setup(struct pci_dev *ALI15X3_dev)
122 {
123 u16 a;
124 unsigned char temp;
125
126 /* Check the following things:
127 - SMB I/O address is initialized
128 - Device is enabled
129 - We can use the addresses
130 */
131
132 /* Unlock the register.
133 The data sheet says that the address registers are read-only
134 if the lock bits are 1, but in fact the address registers
135 are zero unless you clear the lock bits.
136 */
137 pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
138 if (temp & ALI15X3_LOCK) {
139 temp &= ~ALI15X3_LOCK;
140 pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
141 }
142
143 /* Determine the address of the SMBus area */
144 pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
145 ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
146 if (ali15x3_smba == 0 && force_addr == 0) {
147 dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
148 "- upgrade BIOS or use force_addr=0xaddr\n");
149 return -ENODEV;
150 }
151
152 if(force_addr)
153 ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
154
155 if (acpi_check_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
156 ali15x3_driver.name))
157 return -EBUSY;
158
159 if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
160 ali15x3_driver.name)) {
161 dev_err(&ALI15X3_dev->dev,
162 "ALI15X3_smb region 0x%x already in use!\n",
163 ali15x3_smba);
164 return -ENODEV;
165 }
166
167 if(force_addr) {
168 dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
169 ali15x3_smba);
170 if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
171 SMBBA,
172 ali15x3_smba))
173 goto error;
174 if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
175 SMBBA, &a))
176 goto error;
177 if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
178 /* make sure it works */
179 dev_err(&ALI15X3_dev->dev,
180 "force address failed - not supported?\n");
181 goto error;
182 }
183 }
184 /* check if whole device is enabled */
185 pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
186 if ((temp & 1) == 0) {
187 dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
188 pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
189 }
190
191 /* Is SMB Host controller enabled? */
192 pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
193 if ((temp & 1) == 0) {
194 dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
195 pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
196 }
197
198 /* set SMB clock to 74KHz as recommended in data sheet */
199 pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
200
201 /*
202 The interrupt routing for SMB is set up in register 0x77 in the
203 1533 ISA Bridge device, NOT in the 7101 device.
204 Don't bother with finding the 1533 device and reading the register.
205 if ((....... & 0x0F) == 1)
206 dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
207 */
208 pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
209 dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
210 dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
211
212 return 0;
213 error:
214 release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
215 return -ENODEV;
216 }
217
218 /* Another internally used function */
ali15x3_transaction(struct i2c_adapter * adap)219 static int ali15x3_transaction(struct i2c_adapter *adap)
220 {
221 int temp;
222 int result = 0;
223 int timeout = 0;
224
225 dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
226 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
227 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
228 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
229
230 /* get status */
231 temp = inb_p(SMBHSTSTS);
232
233 /* Make sure the SMBus host is ready to start transmitting */
234 /* Check the busy bit first */
235 if (temp & ALI15X3_STS_BUSY) {
236 /*
237 If the host controller is still busy, it may have timed out in the
238 previous transaction, resulting in a "SMBus Timeout" Dev.
239 I've tried the following to reset a stuck busy bit.
240 1. Reset the controller with an ABORT command.
241 (this doesn't seem to clear the controller if an external
242 device is hung)
243 2. Reset the controller and the other SMBus devices with a
244 T_OUT command. (this clears the host busy bit if an
245 external device is hung, but it comes back upon a new access
246 to a device)
247 3. Disable and reenable the controller in SMBHSTCFG
248 Worst case, nothing seems to work except power reset.
249 */
250 /* Abort - reset the host controller */
251 /*
252 Try resetting entire SMB bus, including other devices -
253 This may not work either - it clears the BUSY bit but
254 then the BUSY bit may come back on when you try and use the chip again.
255 If that's the case you are stuck.
256 */
257 dev_info(&adap->dev, "Resetting entire SMB Bus to "
258 "clear busy condition (%02x)\n", temp);
259 outb_p(ALI15X3_T_OUT, SMBHSTCNT);
260 temp = inb_p(SMBHSTSTS);
261 }
262
263 /* now check the error bits and the busy bit */
264 if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
265 /* do a clear-on-write */
266 outb_p(0xFF, SMBHSTSTS);
267 if ((temp = inb_p(SMBHSTSTS)) &
268 (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
269 /* this is probably going to be correctable only by a power reset
270 as one of the bits now appears to be stuck */
271 /* This may be a bus or device with electrical problems. */
272 dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
273 "controller or device on bus is probably hung\n",
274 temp);
275 return -EBUSY;
276 }
277 } else {
278 /* check and clear done bit */
279 if (temp & ALI15X3_STS_DONE) {
280 outb_p(temp, SMBHSTSTS);
281 }
282 }
283
284 /* start the transaction by writing anything to the start register */
285 outb_p(0xFF, SMBHSTSTART);
286
287 /* We will always wait for a fraction of a second! */
288 timeout = 0;
289 do {
290 msleep(1);
291 temp = inb_p(SMBHSTSTS);
292 } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
293 && (timeout++ < MAX_TIMEOUT));
294
295 /* If the SMBus is still busy, we give up */
296 if (timeout > MAX_TIMEOUT) {
297 result = -ETIMEDOUT;
298 dev_err(&adap->dev, "SMBus Timeout!\n");
299 }
300
301 if (temp & ALI15X3_STS_TERM) {
302 result = -EIO;
303 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
304 }
305
306 /*
307 Unfortunately the ALI SMB controller maps "no response" and "bus
308 collision" into a single bit. No response is the usual case so don't
309 do a printk.
310 This means that bus collisions go unreported.
311 */
312 if (temp & ALI15X3_STS_COLL) {
313 result = -ENXIO;
314 dev_dbg(&adap->dev,
315 "Error: no response or bus collision ADD=%02x\n",
316 inb_p(SMBHSTADD));
317 }
318
319 /* haven't ever seen this */
320 if (temp & ALI15X3_STS_DEV) {
321 result = -EIO;
322 dev_err(&adap->dev, "Error: device error\n");
323 }
324 dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
325 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
326 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
327 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
328 return result;
329 }
330
331 /* Return negative errno on error. */
ali15x3_access(struct i2c_adapter * adap,u16 addr,unsigned short flags,char read_write,u8 command,int size,union i2c_smbus_data * data)332 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
333 unsigned short flags, char read_write, u8 command,
334 int size, union i2c_smbus_data * data)
335 {
336 int i, len;
337 int temp;
338 int timeout;
339
340 /* clear all the bits (clear-on-write) */
341 outb_p(0xFF, SMBHSTSTS);
342 /* make sure SMBus is idle */
343 temp = inb_p(SMBHSTSTS);
344 for (timeout = 0;
345 (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
346 timeout++) {
347 msleep(1);
348 temp = inb_p(SMBHSTSTS);
349 }
350 if (timeout >= MAX_TIMEOUT) {
351 dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
352 }
353
354 switch (size) {
355 case I2C_SMBUS_QUICK:
356 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
357 SMBHSTADD);
358 size = ALI15X3_QUICK;
359 break;
360 case I2C_SMBUS_BYTE:
361 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
362 SMBHSTADD);
363 if (read_write == I2C_SMBUS_WRITE)
364 outb_p(command, SMBHSTCMD);
365 size = ALI15X3_BYTE;
366 break;
367 case I2C_SMBUS_BYTE_DATA:
368 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
369 SMBHSTADD);
370 outb_p(command, SMBHSTCMD);
371 if (read_write == I2C_SMBUS_WRITE)
372 outb_p(data->byte, SMBHSTDAT0);
373 size = ALI15X3_BYTE_DATA;
374 break;
375 case I2C_SMBUS_WORD_DATA:
376 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
377 SMBHSTADD);
378 outb_p(command, SMBHSTCMD);
379 if (read_write == I2C_SMBUS_WRITE) {
380 outb_p(data->word & 0xff, SMBHSTDAT0);
381 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
382 }
383 size = ALI15X3_WORD_DATA;
384 break;
385 case I2C_SMBUS_BLOCK_DATA:
386 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
387 SMBHSTADD);
388 outb_p(command, SMBHSTCMD);
389 if (read_write == I2C_SMBUS_WRITE) {
390 len = data->block[0];
391 if (len < 0) {
392 len = 0;
393 data->block[0] = len;
394 }
395 if (len > 32) {
396 len = 32;
397 data->block[0] = len;
398 }
399 outb_p(len, SMBHSTDAT0);
400 /* Reset SMBBLKDAT */
401 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
402 for (i = 1; i <= len; i++)
403 outb_p(data->block[i], SMBBLKDAT);
404 }
405 size = ALI15X3_BLOCK_DATA;
406 break;
407 default:
408 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
409 return -EOPNOTSUPP;
410 }
411
412 outb_p(size, SMBHSTCNT); /* output command */
413
414 temp = ali15x3_transaction(adap);
415 if (temp)
416 return temp;
417
418 if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
419 return 0;
420
421
422 switch (size) {
423 case ALI15X3_BYTE: /* Result put in SMBHSTDAT0 */
424 data->byte = inb_p(SMBHSTDAT0);
425 break;
426 case ALI15X3_BYTE_DATA:
427 data->byte = inb_p(SMBHSTDAT0);
428 break;
429 case ALI15X3_WORD_DATA:
430 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
431 break;
432 case ALI15X3_BLOCK_DATA:
433 len = inb_p(SMBHSTDAT0);
434 if (len > 32)
435 len = 32;
436 data->block[0] = len;
437 /* Reset SMBBLKDAT */
438 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
439 for (i = 1; i <= data->block[0]; i++) {
440 data->block[i] = inb_p(SMBBLKDAT);
441 dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
442 len, i, data->block[i]);
443 }
444 break;
445 }
446 return 0;
447 }
448
ali15x3_func(struct i2c_adapter * adapter)449 static u32 ali15x3_func(struct i2c_adapter *adapter)
450 {
451 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
452 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
453 I2C_FUNC_SMBUS_BLOCK_DATA;
454 }
455
456 static const struct i2c_algorithm smbus_algorithm = {
457 .smbus_xfer = ali15x3_access,
458 .functionality = ali15x3_func,
459 };
460
461 static struct i2c_adapter ali15x3_adapter = {
462 .owner = THIS_MODULE,
463 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
464 .algo = &smbus_algorithm,
465 };
466
467 static const struct pci_device_id ali15x3_ids[] = {
468 { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
469 { 0, }
470 };
471
472 MODULE_DEVICE_TABLE (pci, ali15x3_ids);
473
ali15x3_probe(struct pci_dev * dev,const struct pci_device_id * id)474 static int ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
475 {
476 if (ali15x3_setup(dev)) {
477 dev_err(&dev->dev,
478 "ALI15X3 not detected, module not inserted.\n");
479 return -ENODEV;
480 }
481
482 /* set up the sysfs linkage to our parent device */
483 ali15x3_adapter.dev.parent = &dev->dev;
484
485 snprintf(ali15x3_adapter.name, sizeof(ali15x3_adapter.name),
486 "SMBus ALI15X3 adapter at %04x", ali15x3_smba);
487 return i2c_add_adapter(&ali15x3_adapter);
488 }
489
ali15x3_remove(struct pci_dev * dev)490 static void ali15x3_remove(struct pci_dev *dev)
491 {
492 i2c_del_adapter(&ali15x3_adapter);
493 release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
494 }
495
496 static struct pci_driver ali15x3_driver = {
497 .name = "ali15x3_smbus",
498 .id_table = ali15x3_ids,
499 .probe = ali15x3_probe,
500 .remove = ali15x3_remove,
501 };
502
503 module_pci_driver(ali15x3_driver);
504
505 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
506 MODULE_AUTHOR("Philip Edelbrock <phil@netroedge.com>");
507 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
508 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
509 MODULE_LICENSE("GPL");
510