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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,
221 "%s in state %s (addr=0x%02x, len=%d, status=0x%02x)\n", errmsg,
222 scx200_acb_state_name[iface->state], iface->address_byte,
223 iface->len, status);
224
225 iface->state = state_idle;
226 iface->result = -EIO;
227 iface->needs_reset = 1;
228}
229
230static void scx200_acb_poll(struct scx200_acb_iface *iface)
231{
232 u8 status;
233 unsigned long timeout;
234
235 timeout = jiffies + POLL_TIMEOUT;
236 while (1) {
237 status = inb(ACBST);
238
239
240 outb(0, ACBST);
241
242 if ((status & (ACBST_SDAST|ACBST_BER|ACBST_NEGACK)) != 0) {
243 scx200_acb_machine(iface, status);
244 return;
245 }
246 if (time_after(jiffies, timeout))
247 break;
248 cpu_relax();
249 cond_resched();
250 }
251
252 dev_err(&iface->adapter.dev, "timeout in state %s\n",
253 scx200_acb_state_name[iface->state]);
254
255 iface->state = state_idle;
256 iface->result = -EIO;
257 iface->needs_reset = 1;
258}
259
260static void scx200_acb_reset(struct scx200_acb_iface *iface)
261{
262
263
264 outb(0x70, ACBCTL2);
265
266 outb(0, ACBCTL1);
267
268 outb(0, ACBADDR);
269
270 outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
271
272 outb(inb(ACBCTL1) & ~(ACBCTL1_STASTRE | ACBCTL1_NMINTE), ACBCTL1);
273
274 outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
275
276 outb(ACBST_BER | ACBST_NEGACK | ACBST_STASTR, ACBST);
277
278 outb(inb(ACBCST) | ACBCST_BB, ACBCST);
279}
280
281static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
282 u16 address, unsigned short flags,
283 char rw, u8 command, int size,
284 union i2c_smbus_data *data)
285{
286 struct scx200_acb_iface *iface = i2c_get_adapdata(adapter);
287 int len;
288 u8 *buffer;
289 u16 cur_word;
290 int rc;
291
292 switch (size) {
293 case I2C_SMBUS_QUICK:
294 len = 0;
295 buffer = NULL;
296 break;
297
298 case I2C_SMBUS_BYTE:
299 len = 1;
300 buffer = rw ? &data->byte : &command;
301 break;
302
303 case I2C_SMBUS_BYTE_DATA:
304 len = 1;
305 buffer = &data->byte;
306 break;
307
308 case I2C_SMBUS_WORD_DATA:
309 len = 2;
310 cur_word = cpu_to_le16(data->word);
311 buffer = (u8 *)&cur_word;
312 break;
313
314 case I2C_SMBUS_I2C_BLOCK_DATA:
315 len = data->block[0];
316 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
317 return -EINVAL;
318 buffer = &data->block[1];
319 break;
320
321 default:
322 return -EINVAL;
323 }
324
325 dev_dbg(&adapter->dev,
326 "size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
327 size, address, command, len, rw);
328
329 if (!len && rw == I2C_SMBUS_READ) {
330 dev_dbg(&adapter->dev, "zero length read\n");
331 return -EINVAL;
332 }
333
334 mutex_lock(&iface->mutex);
335
336 iface->address_byte = (address << 1) | rw;
337 iface->command = command;
338 iface->ptr = buffer;
339 iface->len = len;
340 iface->result = -EINVAL;
341 iface->needs_reset = 0;
342
343 outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
344
345 if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE)
346 iface->state = state_quick;
347 else
348 iface->state = state_address;
349
350 while (iface->state != state_idle)
351 scx200_acb_poll(iface);
352
353 if (iface->needs_reset)
354 scx200_acb_reset(iface);
355
356 rc = iface->result;
357
358 mutex_unlock(&iface->mutex);
359
360 if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ)
361 data->word = le16_to_cpu(cur_word);
362
363#ifdef DEBUG
364 dev_dbg(&adapter->dev, "transfer done, result: %d", rc);
365 if (buffer) {
366 int i;
367 printk(" data:");
368 for (i = 0; i < len; ++i)
369 printk(" %02x", buffer[i]);
370 }
371 printk("\n");
372#endif
373
374 return rc;
375}
376
377static u32 scx200_acb_func(struct i2c_adapter *adapter)
378{
379 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
380 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
381 I2C_FUNC_SMBUS_I2C_BLOCK;
382}
383
384
385static const struct i2c_algorithm scx200_acb_algorithm = {
386 .smbus_xfer = scx200_acb_smbus_xfer,
387 .functionality = scx200_acb_func,
388};
389
390static struct scx200_acb_iface *scx200_acb_list;
391static DEFINE_MUTEX(scx200_acb_list_mutex);
392
393static __init int scx200_acb_probe(struct scx200_acb_iface *iface)
394{
395 u8 val;
396
397
398
399 outb(0x70, ACBCTL2);
400
401 if (inb(ACBCTL2) != 0x70) {
402 pr_debug(NAME ": ACBCTL2 readback failed\n");
403 return -ENXIO;
404 }
405
406 outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
407
408 val = inb(ACBCTL1);
409 if (val) {
410 pr_debug(NAME ": disabled, but ACBCTL1=0x%02x\n",
411 val);
412 return -ENXIO;
413 }
414
415 outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
416
417 outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
418
419 val = inb(ACBCTL1);
420 if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) {
421 pr_debug(NAME ": enabled, but NMINTE won't be set, "
422 "ACBCTL1=0x%02x\n", val);
423 return -ENXIO;
424 }
425
426 return 0;
427}
428
429static __init struct scx200_acb_iface *scx200_create_iface(const char *text,
430 struct device *dev, int index)
431{
432 struct scx200_acb_iface *iface;
433 struct i2c_adapter *adapter;
434
435 iface = kzalloc(sizeof(*iface), GFP_KERNEL);
436 if (!iface) {
437 printk(KERN_ERR NAME ": can't allocate memory\n");
438 return NULL;
439 }
440
441 adapter = &iface->adapter;
442 i2c_set_adapdata(adapter, iface);
443 snprintf(adapter->name, sizeof(adapter->name), "%s ACB%d", text, index);
444 adapter->owner = THIS_MODULE;
445 adapter->algo = &scx200_acb_algorithm;
446 adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
447 adapter->dev.parent = dev;
448
449 mutex_init(&iface->mutex);
450
451 return iface;
452}
453
454static int __init scx200_acb_create(struct scx200_acb_iface *iface)
455{
456 struct i2c_adapter *adapter;
457 int rc;
458
459 adapter = &iface->adapter;
460
461 rc = scx200_acb_probe(iface);
462 if (rc) {
463 printk(KERN_WARNING NAME ": probe failed\n");
464 return rc;
465 }
466
467 scx200_acb_reset(iface);
468
469 if (i2c_add_adapter(adapter) < 0) {
470 printk(KERN_ERR NAME ": failed to register\n");
471 return -ENODEV;
472 }
473
474 mutex_lock(&scx200_acb_list_mutex);
475 iface->next = scx200_acb_list;
476 scx200_acb_list = iface;
477 mutex_unlock(&scx200_acb_list_mutex);
478
479 return 0;
480}
481
482static __init int scx200_create_pci(const char *text, struct pci_dev *pdev,
483 int bar)
484{
485 struct scx200_acb_iface *iface;
486 int rc;
487
488 iface = scx200_create_iface(text, &pdev->dev, 0);
489
490 if (iface == NULL)
491 return -ENOMEM;
492
493 iface->pdev = pdev;
494 iface->bar = bar;
495
496 rc = pci_enable_device_io(iface->pdev);
497 if (rc)
498 goto errout_free;
499
500 rc = pci_request_region(iface->pdev, iface->bar, iface->adapter.name);
501 if (rc) {
502 printk(KERN_ERR NAME ": can't allocate PCI BAR %d\n",
503 iface->bar);
504 goto errout_free;
505 }
506
507 iface->base = pci_resource_start(iface->pdev, iface->bar);
508 rc = scx200_acb_create(iface);
509
510 if (rc == 0)
511 return 0;
512
513 pci_release_region(iface->pdev, iface->bar);
514 pci_dev_put(iface->pdev);
515 errout_free:
516 kfree(iface);
517 return rc;
518}
519
520static int __init scx200_create_isa(const char *text, unsigned long base,
521 int index)
522{
523 struct scx200_acb_iface *iface;
524 int rc;
525
526 iface = scx200_create_iface(text, NULL, index);
527
528 if (iface == NULL)
529 return -ENOMEM;
530
531 if (!request_region(base, 8, iface->adapter.name)) {
532 printk(KERN_ERR NAME ": can't allocate io 0x%lx-0x%lx\n",
533 base, base + 8 - 1);
534 rc = -EBUSY;
535 goto errout_free;
536 }
537
538 iface->base = base;
539 rc = scx200_acb_create(iface);
540
541 if (rc == 0)
542 return 0;
543
544 release_region(base, 8);
545 errout_free:
546 kfree(iface);
547 return rc;
548}
549
550
551
552
553
554static struct pci_device_id scx200_pci[] = {
555 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE),
556 .driver_data = 0 },
557 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE),
558 .driver_data = 0 },
559 { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA),
560 .driver_data = 1 },
561 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA),
562 .driver_data = 2 }
563};
564
565static struct {
566 const char *name;
567 int bar;
568} scx200_data[] = {
569 { "SCx200", -1 },
570 { "CS5535", 0 },
571 { "CS5536", 0 }
572};
573
574static __init int scx200_scan_pci(void)
575{
576 int data, dev;
577 int rc = -ENODEV;
578 struct pci_dev *pdev;
579
580 for(dev = 0; dev < ARRAY_SIZE(scx200_pci); dev++) {
581 pdev = pci_get_device(scx200_pci[dev].vendor,
582 scx200_pci[dev].device, NULL);
583
584 if (pdev == NULL)
585 continue;
586
587 data = scx200_pci[dev].driver_data;
588
589
590
591
592
593
594 if (scx200_data[data].bar >= 0)
595 rc = scx200_create_pci(scx200_data[data].name, pdev,
596 scx200_data[data].bar);
597 else {
598 int i;
599
600 pci_dev_put(pdev);
601 for (i = 0; i < MAX_DEVICES; ++i) {
602 if (base[i] == 0)
603 continue;
604
605 rc = scx200_create_isa(scx200_data[data].name,
606 base[i],
607 i);
608 }
609 }
610
611 break;
612 }
613
614 return rc;
615}
616
617static int __init scx200_acb_init(void)
618{
619 int rc;
620
621 pr_debug(NAME ": NatSemi SCx200 ACCESS.bus Driver\n");
622
623 rc = scx200_scan_pci();
624
625
626 if (scx200_acb_list)
627 return 0;
628 return rc;
629}
630
631static void __exit scx200_acb_cleanup(void)
632{
633 struct scx200_acb_iface *iface;
634
635 mutex_lock(&scx200_acb_list_mutex);
636 while ((iface = scx200_acb_list) != NULL) {
637 scx200_acb_list = iface->next;
638 mutex_unlock(&scx200_acb_list_mutex);
639
640 i2c_del_adapter(&iface->adapter);
641
642 if (iface->pdev) {
643 pci_release_region(iface->pdev, iface->bar);
644 pci_dev_put(iface->pdev);
645 }
646 else
647 release_region(iface->base, 8);
648
649 kfree(iface);
650 mutex_lock(&scx200_acb_list_mutex);
651 }
652 mutex_unlock(&scx200_acb_list_mutex);
653}
654
655module_init(scx200_acb_init);
656module_exit(scx200_acb_cleanup);
657
