1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26#include <linux/module.h>
27#include <linux/errno.h>
28#include <linux/kernel.h>
29#include <linux/init.h>
30#include <linux/i2c.h>
31#include <linux/pci.h>
32#include <linux/delay.h>
33#include <linux/mutex.h>
34#include <asm/io.h>
35
36#include <linux/scx200.h>
37
38#define NAME "scx200_acb"
39
40MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
41MODULE_DESCRIPTION("NatSemi SCx200 ACCESS.bus Driver");
42MODULE_LICENSE("GPL");
43
44#define MAX_DEVICES 4
45static int base[MAX_DEVICES] = { 0x820, 0x840 };
46module_param_array(base, int, NULL, 0);
47MODULE_PARM_DESC(base, "Base addresses for the ACCESS.bus controllers");
48
49#define POLL_TIMEOUT (HZ/5)
50
51enum scx200_acb_state {
52 state_idle,
53 state_address,
54 state_command,
55 state_repeat_start,
56 state_quick,
57 state_read,
58 state_write,
59};
60
61static const char *scx200_acb_state_name[] = {
62 "idle",
63 "address",
64 "command",
65 "repeat_start",
66 "quick",
67 "read",
68 "write",
69};
70
71
72struct scx200_acb_iface {
73 struct scx200_acb_iface *next;
74 struct i2c_adapter adapter;
75 unsigned base;
76 struct mutex mutex;
77
78
79 enum scx200_acb_state state;
80 int result;
81 u8 address_byte;
82 u8 command;
83 u8 *ptr;
84 char needs_reset;
85 unsigned len;
86
87
88 struct pci_dev *pdev;
89 int bar;
90};
91
92
93#define ACBSDA (iface->base + 0)
94#define ACBST (iface->base + 1)
95#define ACBST_SDAST 0x40
96#define ACBST_BER 0x20
97#define ACBST_NEGACK 0x10
98#define ACBST_STASTR 0x08
99#define ACBST_MASTER 0x02
100#define ACBCST (iface->base + 2)
101#define ACBCST_BB 0x02
102#define ACBCTL1 (iface->base + 3)
103#define ACBCTL1_STASTRE 0x80
104#define ACBCTL1_NMINTE 0x40
105#define ACBCTL1_ACK 0x10
106#define ACBCTL1_STOP 0x02
107#define ACBCTL1_START 0x01
108#define ACBADDR (iface->base + 4)
109#define ACBCTL2 (iface->base + 5)
110#define ACBCTL2_ENABLE 0x01
111
112
113
114static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
115{
116 const char *errmsg;
117
118 dev_dbg(&iface->adapter.dev, "state %s, status = 0x%02x\n",
119 scx200_acb_state_name[iface->state], status);
120
121 if (status & ACBST_BER) {
122 errmsg = "bus error";
123 goto error;
124 }
125 if (!(status & ACBST_MASTER)) {
126 errmsg = "not master";
127 goto error;
128 }
129 if (status & ACBST_NEGACK) {
130 dev_dbg(&iface->adapter.dev, "negative ack in state %s\n",
131 scx200_acb_state_name[iface->state]);
132
133 iface->state = state_idle;
134 iface->result = -ENXIO;
135
136 outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
137 outb(ACBST_STASTR | ACBST_NEGACK, ACBST);
138
139
140 outb(0, ACBST);
141 return;
142 }
143
144 switch (iface->state) {
145 case state_idle:
146 dev_warn(&iface->adapter.dev, "interrupt in idle state\n");
147 break;
148
149 case state_address:
150
151 outb(iface->address_byte & ~1, ACBSDA);
152
153 iface->state = state_command;
154 break;
155
156 case state_command:
157 outb(iface->command, ACBSDA);
158
159 if (iface->address_byte & 1)
160 iface->state = state_repeat_start;
161 else
162 iface->state = state_write;
163 break;
164
165 case state_repeat_start:
166 outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
167
168
169 case state_quick:
170 if (iface->address_byte & 1) {
171 if (iface->len == 1)
172 outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
173 else
174 outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
175 outb(iface->address_byte, ACBSDA);
176
177 iface->state = state_read;
178 } else {
179 outb(iface->address_byte, ACBSDA);
180
181 iface->state = state_write;
182 }
183 break;
184
185 case state_read:
186
187 if (iface->len == 2)
188 outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
189 else
190 outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
191
192 if (iface->len == 1) {
193 iface->result = 0;
194 iface->state = state_idle;
195 outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
196 }
197
198 *iface->ptr++ = inb(ACBSDA);
199 --iface->len;
200
201 break;
202
203 case state_write:
204 if (iface->len == 0) {
205 iface->result = 0;
206 iface->state = state_idle;
207 outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
208 break;
209 }
210
211 outb(*iface->ptr++, ACBSDA);
212 --iface->len;
213
214 break;
215 }
216
217 return;
218
219 error:
220 dev_err(&iface->adapter.dev, "%s in state %s\n", errmsg,
221 scx200_acb_state_name[iface->state]);
222
223 iface->state = state_idle;
224 iface->result = -EIO;
225 iface->needs_reset = 1;
226}
227
228static void scx200_acb_poll(struct scx200_acb_iface *iface)
229{
230 u8 status;
231 unsigned long timeout;
232
233 timeout = jiffies + POLL_TIMEOUT;
234 while (1) {
235 status = inb(ACBST);
236
237
238 outb(0, ACBST);
239
240 if ((status & (ACBST_SDAST|ACBST_BER|ACBST_NEGACK)) != 0) {
241 scx200_acb_machine(iface, status);
242 return;
243 }
244 if (time_after(jiffies, timeout))
245 break;
246 cpu_relax();
247 cond_resched();
248 }
249
250 dev_err(&iface->adapter.dev, "timeout in state %s\n",
251 scx200_acb_state_name[iface->state]);
252
253 iface->state = state_idle;
254 iface->result = -EIO;
255 iface->needs_reset = 1;
256}
257
258static void scx200_acb_reset(struct scx200_acb_iface *iface)
259{
260
261
262 outb(0x70, ACBCTL2);
263
264 outb(0, ACBCTL1);
265
266 outb(0, ACBADDR);
267
268 outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
269
270 outb(inb(ACBCTL1) & ~(ACBCTL1_STASTRE | ACBCTL1_NMINTE), ACBCTL1);
271
272 outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
273
274 outb(ACBST_BER | ACBST_NEGACK | ACBST_STASTR, ACBST);
275
276 outb(inb(ACBCST) | ACBCST_BB, ACBCST);
277}
278
279static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
280 u16 address, unsigned short flags,
281 char rw, u8 command, int size,
282 union i2c_smbus_data *data)
283{
284 struct scx200_acb_iface *iface = i2c_get_adapdata(adapter);
285 int len;
286 u8 *buffer;
287 u16 cur_word;
288 int rc;
289
290 switch (size) {
291 case I2C_SMBUS_QUICK:
292 len = 0;
293 buffer = NULL;
294 break;
295
296 case I2C_SMBUS_BYTE:
297 len = 1;
298 buffer = rw ? &data->byte : &command;
299 break;
300
301 case I2C_SMBUS_BYTE_DATA:
302 len = 1;
303 buffer = &data->byte;
304 break;
305
306 case I2C_SMBUS_WORD_DATA:
307 len = 2;
308 cur_word = cpu_to_le16(data->word);
309 buffer = (u8 *)&cur_word;
310 break;
311
312 case I2C_SMBUS_I2C_BLOCK_DATA:
313 len = data->block[0];
314 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
315 return -EINVAL;
316 buffer = &data->block[1];
317 break;
318
319 default:
320 return -EINVAL;
321 }
322
323 dev_dbg(&adapter->dev,
324 "size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
325 size, address, command, len, rw);
326
327 if (!len && rw == I2C_SMBUS_READ) {
328 dev_dbg(&adapter->dev, "zero length read\n");
329 return -EINVAL;
330 }
331
332 mutex_lock(&iface->mutex);
333
334 iface->address_byte = (address << 1) | rw;
335 iface->command = command;
336 iface->ptr = buffer;
337 iface->len = len;
338 iface->result = -EINVAL;
339 iface->needs_reset = 0;
340
341 outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
342
343 if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE)
344 iface->state = state_quick;
345 else
346 iface->state = state_address;
347
348 while (iface->state != state_idle)
349 scx200_acb_poll(iface);
350
351 if (iface->needs_reset)
352 scx200_acb_reset(iface);
353
354 rc = iface->result;
355
356 mutex_unlock(&iface->mutex);
357
358 if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ)
359 data->word = le16_to_cpu(cur_word);
360
361#ifdef DEBUG
362 dev_dbg(&adapter->dev, "transfer done, result: %d", rc);
363 if (buffer) {
364 int i;
365 printk(" data:");
366 for (i = 0; i < len; ++i)
367 printk(" %02x", buffer[i]);
368 }
369 printk("\n");
370#endif
371
372 return rc;
373}
374
375static u32 scx200_acb_func(struct i2c_adapter *adapter)
376{
377 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
378 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
379 I2C_FUNC_SMBUS_I2C_BLOCK;
380}
381
382
383static const struct i2c_algorithm scx200_acb_algorithm = {
384 .smbus_xfer = scx200_acb_smbus_xfer,
385 .functionality = scx200_acb_func,
386};
387
388static struct scx200_acb_iface *scx200_acb_list;
389static DEFINE_MUTEX(scx200_acb_list_mutex);
390
391static __init int scx200_acb_probe(struct scx200_acb_iface *iface)
392{
393 u8 val;
394
395
396
397 outb(0x70, ACBCTL2);
398
399 if (inb(ACBCTL2) != 0x70) {
400 pr_debug(NAME ": ACBCTL2 readback failed\n");
401 return -ENXIO;
402 }
403
404 outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
405
406 val = inb(ACBCTL1);
407 if (val) {
408 pr_debug(NAME ": disabled, but ACBCTL1=0x%02x\n",
409 val);
410 return -ENXIO;
411 }
412
413 outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
414
415 outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
416
417 val = inb(ACBCTL1);
418 if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) {
419 pr_debug(NAME ": enabled, but NMINTE won't be set, "
420 "ACBCTL1=0x%02x\n", val);
421 return -ENXIO;
422 }
423
424 return 0;
425}
426
427static __init struct scx200_acb_iface *scx200_create_iface(const char *text,
428 struct device *dev, int index)
429{
430 struct scx200_acb_iface *iface;
431 struct i2c_adapter *adapter;
432
433 iface = kzalloc(sizeof(*iface), GFP_KERNEL);
434 if (!iface) {
435 printk(KERN_ERR NAME ": can't allocate memory\n");
436 return NULL;
437 }
438
439 adapter = &iface->adapter;
440 i2c_set_adapdata(adapter, iface);
441 snprintf(adapter->name, sizeof(adapter->name), "%s ACB%d", text, index);
442 adapter->owner = THIS_MODULE;
443 adapter->id = I2C_HW_SMBUS_SCX200;
444 adapter->algo = &scx200_acb_algorithm;
445 adapter->class = I2C_CLASS_HWMON;
446 adapter->dev.parent = dev;
447
448 mutex_init(&iface->mutex);
449
450 return iface;
451}
452
453static int __init scx200_acb_create(struct scx200_acb_iface *iface)
454{
455 struct i2c_adapter *adapter;
456 int rc;
457
458 adapter = &iface->adapter;
459
460 rc = scx200_acb_probe(iface);
461 if (rc) {
462 printk(KERN_WARNING NAME ": probe failed\n");
463 return rc;
464 }
465
466 scx200_acb_reset(iface);
467
468 if (i2c_add_adapter(adapter) < 0) {
469 printk(KERN_ERR NAME ": failed to register\n");
470 return -ENODEV;
471 }
472
473 mutex_lock(&scx200_acb_list_mutex);
474 iface->next = scx200_acb_list;
475 scx200_acb_list = iface;
476 mutex_unlock(&scx200_acb_list_mutex);
477
478 return 0;
479}
480
481static __init int scx200_create_pci(const char *text, struct pci_dev *pdev,
482 int bar)
483{
484 struct scx200_acb_iface *iface;
485 int rc;
486
487 iface = scx200_create_iface(text, &pdev->dev, 0);
488
489 if (iface == NULL)
490 return -ENOMEM;
491
492 iface->pdev = pdev;
493 iface->bar = bar;
494
495 rc = pci_enable_device_bars(iface->pdev, 1 << iface->bar);
496 if (rc)
497 goto errout_free;
498
499 rc = pci_request_region(iface->pdev, iface->bar, iface->adapter.name);
500 if (rc) {
501 printk(KERN_ERR NAME ": can't allocate PCI BAR %d\n",
502 iface->bar);
503 goto errout_free;
504 }
505
506 iface->base = pci_resource_start(iface->pdev, iface->bar);
507 rc = scx200_acb_create(iface);
508
509 if (rc == 0)
510 return 0;
511
512 pci_release_region(iface->pdev, iface->bar);
513 pci_dev_put(iface->pdev);
514 errout_free:
515 kfree(iface);
516 return rc;
517}
518
519static int __init scx200_create_isa(const char *text, unsigned long base,
520 int index)
521{
522 struct scx200_acb_iface *iface;
523 int rc;
524
525 iface = scx200_create_iface(text, NULL, index);
526
527 if (iface == NULL)
528 return -ENOMEM;
529
530 if (request_region(base, 8, iface->adapter.name) == 0) {
531 printk(KERN_ERR NAME ": can't allocate io 0x%lx-0x%lx\n",
532 base, base + 8 - 1);
533 rc = -EBUSY;
534 goto errout_free;
535 }
536
537 iface->base = base;
538 rc = scx200_acb_create(iface);
539
540 if (rc == 0)
541 return 0;
542
543 release_region(base, 8);
544 errout_free:
545 kfree(iface);
546 return rc;
547}
548
549
550
551
552
553static struct pci_device_id scx200_pci[] = {
554 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE),
555 .driver_data = 0 },
556 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE),
557 .driver_data = 0 },
558 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA),
559 .driver_data = 1 },
560 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA),
561 .driver_data = 2 }
562};
563
564static struct {
565 const char *name;
566 int bar;
567} scx200_data[] = {
568 { "SCx200", -1 },
569 { "CS5535", 0 },
570 { "CS5536", 0 }
571};
572
573static __init int scx200_scan_pci(void)
574{
575 int data, dev;
576 int rc = -ENODEV;
577 struct pci_dev *pdev;
578
579 for(dev = 0; dev < ARRAY_SIZE(scx200_pci); dev++) {
580 pdev = pci_get_device(scx200_pci[dev].vendor,
581 scx200_pci[dev].device, NULL);
582
583 if (pdev == NULL)
584 continue;
585
586 data = scx200_pci[dev].driver_data;
587
588
589
590
591
592
593 if (scx200_data[data].bar >= 0)
594 rc = scx200_create_pci(scx200_data[data].name, pdev,
595 scx200_data[data].bar);
596 else {
597 int i;
598
599 pci_dev_put(pdev);
600 for (i = 0; i < MAX_DEVICES; ++i) {
601 if (base[i] == 0)
602 continue;
603
604 rc = scx200_create_isa(scx200_data[data].name,
605 base[i],
606 i);
607 }
608 }
609
610 break;
611 }
612
613 return rc;
614}
615
616static int __init scx200_acb_init(void)
617{
618 int rc;
619
620 pr_debug(NAME ": NatSemi SCx200 ACCESS.bus Driver\n");
621
622 rc = scx200_scan_pci();
623
624
625 if (scx200_acb_list)
626 return 0;
627 return rc;
628}
629
630static void __exit scx200_acb_cleanup(void)
631{
632 struct scx200_acb_iface *iface;
633
634 mutex_lock(&scx200_acb_list_mutex);
635 while ((iface = scx200_acb_list) != NULL) {
636 scx200_acb_list = iface->next;
637 mutex_unlock(&scx200_acb_list_mutex);
638
639 i2c_del_adapter(&iface->adapter);
640
641 if (iface->pdev) {
642 pci_release_region(iface->pdev, iface->bar);
643 pci_dev_put(iface->pdev);
644 }
645 else
646 release_region(iface->base, 8);
647
648 kfree(iface);
649 mutex_lock(&scx200_acb_list_mutex);
650 }
651 mutex_unlock(&scx200_acb_list_mutex);
652}
653
654module_init(scx200_acb_init);
655module_exit(scx200_acb_cleanup);
656
