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19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/delay.h>
22#include <linux/slab.h>
23#include <linux/interrupt.h>
24#include <linux/errno.h>
25#include <linux/stddef.h>
26#include <linux/i2c.h>
27#include <linux/io.h>
28#include <linux/dma-mapping.h>
29#include <linux/of_address.h>
30#include <linux/of_device.h>
31#include <linux/of_irq.h>
32#include <linux/of_platform.h>
33#include <sysdev/fsl_soc.h>
34#include <asm/cpm.h>
35
36
37
38#undef I2C_CHIP_ERRATA
39
40#define CPM_MAX_READ 513
41#define CPM_MAXBD 4
42
43#define I2C_EB (0x10)
44#define I2C_EB_CPM2 (0x30)
45
46#define DPRAM_BASE ((u8 __iomem __force *)cpm_muram_addr(0))
47
48
49struct i2c_ram {
50 ushort rbase;
51 ushort tbase;
52 u_char rfcr;
53 u_char tfcr;
54 ushort mrblr;
55 uint rstate;
56 uint rdp;
57 ushort rbptr;
58 ushort rbc;
59 uint rxtmp;
60 uint tstate;
61 uint tdp;
62 ushort tbptr;
63 ushort tbc;
64 uint txtmp;
65 char res1[4];
66 ushort rpbase;
67 char res2[2];
68};
69
70#define I2COM_START 0x80
71#define I2COM_MASTER 0x01
72#define I2CER_TXE 0x10
73#define I2CER_BUSY 0x04
74#define I2CER_TXB 0x02
75#define I2CER_RXB 0x01
76#define I2MOD_EN 0x01
77
78
79struct i2c_reg {
80 u8 i2mod;
81 u8 res1[3];
82 u8 i2add;
83 u8 res2[3];
84 u8 i2brg;
85 u8 res3[3];
86 u8 i2com;
87 u8 res4[3];
88 u8 i2cer;
89 u8 res5[3];
90 u8 i2cmr;
91};
92
93struct cpm_i2c {
94 char *base;
95 struct platform_device *ofdev;
96 struct i2c_adapter adap;
97 uint dp_addr;
98 int version;
99 int irq;
100 int cp_command;
101 int freq;
102 struct i2c_reg __iomem *i2c_reg;
103 struct i2c_ram __iomem *i2c_ram;
104 u16 i2c_addr;
105 wait_queue_head_t i2c_wait;
106 cbd_t __iomem *tbase;
107 cbd_t __iomem *rbase;
108 u_char *txbuf[CPM_MAXBD];
109 u_char *rxbuf[CPM_MAXBD];
110 dma_addr_t txdma[CPM_MAXBD];
111 dma_addr_t rxdma[CPM_MAXBD];
112};
113
114static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id)
115{
116 struct cpm_i2c *cpm;
117 struct i2c_reg __iomem *i2c_reg;
118 struct i2c_adapter *adap = dev_id;
119 int i;
120
121 cpm = i2c_get_adapdata(dev_id);
122 i2c_reg = cpm->i2c_reg;
123
124
125 i = in_8(&i2c_reg->i2cer);
126 out_8(&i2c_reg->i2cer, i);
127
128 dev_dbg(&adap->dev, "Interrupt: %x\n", i);
129
130 wake_up(&cpm->i2c_wait);
131
132 return i ? IRQ_HANDLED : IRQ_NONE;
133}
134
135static void cpm_reset_i2c_params(struct cpm_i2c *cpm)
136{
137 struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
138
139
140 out_be16(&i2c_ram->tbase, (u8 __iomem *)cpm->tbase - DPRAM_BASE);
141 out_be16(&i2c_ram->rbase, (u8 __iomem *)cpm->rbase - DPRAM_BASE);
142
143 if (cpm->version == 1) {
144 out_8(&i2c_ram->tfcr, I2C_EB);
145 out_8(&i2c_ram->rfcr, I2C_EB);
146 } else {
147 out_8(&i2c_ram->tfcr, I2C_EB_CPM2);
148 out_8(&i2c_ram->rfcr, I2C_EB_CPM2);
149 }
150
151 out_be16(&i2c_ram->mrblr, CPM_MAX_READ);
152
153 out_be32(&i2c_ram->rstate, 0);
154 out_be32(&i2c_ram->rdp, 0);
155 out_be16(&i2c_ram->rbptr, 0);
156 out_be16(&i2c_ram->rbc, 0);
157 out_be32(&i2c_ram->rxtmp, 0);
158 out_be32(&i2c_ram->tstate, 0);
159 out_be32(&i2c_ram->tdp, 0);
160 out_be16(&i2c_ram->tbptr, 0);
161 out_be16(&i2c_ram->tbc, 0);
162 out_be32(&i2c_ram->txtmp, 0);
163}
164
165static void cpm_i2c_force_close(struct i2c_adapter *adap)
166{
167 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
168 struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
169
170 dev_dbg(&adap->dev, "cpm_i2c_force_close()\n");
171
172 cpm_command(cpm->cp_command, CPM_CR_CLOSE_RX_BD);
173
174 out_8(&i2c_reg->i2cmr, 0x00);
175 out_8(&i2c_reg->i2cer, 0xff);
176}
177
178static void cpm_i2c_parse_message(struct i2c_adapter *adap,
179 struct i2c_msg *pmsg, int num, int tx, int rx)
180{
181 cbd_t __iomem *tbdf;
182 cbd_t __iomem *rbdf;
183 u_char addr;
184 u_char *tb;
185 u_char *rb;
186 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
187
188 tbdf = cpm->tbase + tx;
189 rbdf = cpm->rbase + rx;
190
191 addr = i2c_8bit_addr_from_msg(pmsg);
192
193 tb = cpm->txbuf[tx];
194 rb = cpm->rxbuf[rx];
195
196
197 rb = (u_char *) (((ulong) rb + 1) & ~1);
198
199 tb[0] = addr;
200
201 out_be16(&tbdf->cbd_datlen, pmsg->len + 1);
202 out_be16(&tbdf->cbd_sc, 0);
203
204 if (!(pmsg->flags & I2C_M_NOSTART))
205 setbits16(&tbdf->cbd_sc, BD_I2C_START);
206
207 if (tx + 1 == num)
208 setbits16(&tbdf->cbd_sc, BD_SC_LAST | BD_SC_WRAP);
209
210 if (pmsg->flags & I2C_M_RD) {
211
212
213
214
215
216
217 dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr);
218
219 out_be16(&rbdf->cbd_datlen, 0);
220 out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
221
222 if (rx + 1 == CPM_MAXBD)
223 setbits16(&rbdf->cbd_sc, BD_SC_WRAP);
224
225 eieio();
226 setbits16(&tbdf->cbd_sc, BD_SC_READY);
227 } else {
228 dev_dbg(&adap->dev, "cpm_i2c_write(abyte=0x%x)\n", addr);
229
230 memcpy(tb+1, pmsg->buf, pmsg->len);
231
232 eieio();
233 setbits16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_INTRPT);
234 }
235}
236
237static int cpm_i2c_check_message(struct i2c_adapter *adap,
238 struct i2c_msg *pmsg, int tx, int rx)
239{
240 cbd_t __iomem *tbdf;
241 cbd_t __iomem *rbdf;
242 u_char *tb;
243 u_char *rb;
244 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
245
246 tbdf = cpm->tbase + tx;
247 rbdf = cpm->rbase + rx;
248
249 tb = cpm->txbuf[tx];
250 rb = cpm->rxbuf[rx];
251
252
253 rb = (u_char *) (((uint) rb + 1) & ~1);
254
255 eieio();
256 if (pmsg->flags & I2C_M_RD) {
257 dev_dbg(&adap->dev, "tx sc 0x%04x, rx sc 0x%04x\n",
258 in_be16(&tbdf->cbd_sc), in_be16(&rbdf->cbd_sc));
259
260 if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
261 dev_dbg(&adap->dev, "I2C read; No ack\n");
262 return -ENXIO;
263 }
264 if (in_be16(&rbdf->cbd_sc) & BD_SC_EMPTY) {
265 dev_err(&adap->dev,
266 "I2C read; complete but rbuf empty\n");
267 return -EREMOTEIO;
268 }
269 if (in_be16(&rbdf->cbd_sc) & BD_SC_OV) {
270 dev_err(&adap->dev, "I2C read; Overrun\n");
271 return -EREMOTEIO;
272 }
273 memcpy(pmsg->buf, rb, pmsg->len);
274 } else {
275 dev_dbg(&adap->dev, "tx sc %d 0x%04x\n", tx,
276 in_be16(&tbdf->cbd_sc));
277
278 if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
279 dev_dbg(&adap->dev, "I2C write; No ack\n");
280 return -ENXIO;
281 }
282 if (in_be16(&tbdf->cbd_sc) & BD_SC_UN) {
283 dev_err(&adap->dev, "I2C write; Underrun\n");
284 return -EIO;
285 }
286 if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
287 dev_err(&adap->dev, "I2C write; Collision\n");
288 return -EIO;
289 }
290 }
291 return 0;
292}
293
294static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
295{
296 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
297 struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
298 struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
299 struct i2c_msg *pmsg;
300 int ret;
301 int tptr;
302 int rptr;
303 cbd_t __iomem *tbdf;
304 cbd_t __iomem *rbdf;
305
306
307 out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
308 out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
309
310 tbdf = cpm->tbase;
311 rbdf = cpm->rbase;
312
313 tptr = 0;
314 rptr = 0;
315
316
317
318
319
320 if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
321 out_8(&cpm->i2c_reg->i2com, I2COM_MASTER);
322 }
323
324 while (tptr < num) {
325 pmsg = &msgs[tptr];
326 dev_dbg(&adap->dev, "R: %d T: %d\n", rptr, tptr);
327
328 cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr);
329 if (pmsg->flags & I2C_M_RD)
330 rptr++;
331 tptr++;
332 }
333
334
335 out_8(&i2c_reg->i2cmr, I2CER_TXE | I2CER_TXB | I2CER_RXB);
336 out_8(&i2c_reg->i2cer, 0xff);
337
338 setbits8(&i2c_reg->i2mod, I2MOD_EN);
339
340 setbits8(&i2c_reg->i2com, I2COM_START);
341
342 tptr = 0;
343 rptr = 0;
344
345 while (tptr < num) {
346
347 dev_dbg(&adap->dev, "test ready.\n");
348 pmsg = &msgs[tptr];
349 if (pmsg->flags & I2C_M_RD)
350 ret = wait_event_timeout(cpm->i2c_wait,
351 (in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) ||
352 !(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY),
353 1 * HZ);
354 else
355 ret = wait_event_timeout(cpm->i2c_wait,
356 !(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_READY),
357 1 * HZ);
358 if (ret == 0) {
359 ret = -EREMOTEIO;
360 dev_err(&adap->dev, "I2C transfer: timeout\n");
361 goto out_err;
362 }
363 if (ret > 0) {
364 dev_dbg(&adap->dev, "ready.\n");
365 ret = cpm_i2c_check_message(adap, pmsg, tptr, rptr);
366 tptr++;
367 if (pmsg->flags & I2C_M_RD)
368 rptr++;
369 if (ret)
370 goto out_err;
371 }
372 }
373#ifdef I2C_CHIP_ERRATA
374
375
376
377
378 udelay(4);
379 clrbits8(&i2c_reg->i2mod, I2MOD_EN);
380#endif
381 return (num);
382
383out_err:
384 cpm_i2c_force_close(adap);
385#ifdef I2C_CHIP_ERRATA
386
387
388
389 clrbits8(&i2c_reg->i2mod, I2MOD_EN);
390#endif
391 return ret;
392}
393
394static u32 cpm_i2c_func(struct i2c_adapter *adap)
395{
396 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
397}
398
399
400
401static const struct i2c_algorithm cpm_i2c_algo = {
402 .master_xfer = cpm_i2c_xfer,
403 .functionality = cpm_i2c_func,
404};
405
406
407static const struct i2c_adapter_quirks cpm_i2c_quirks = {
408 .max_num_msgs = CPM_MAXBD,
409 .max_read_len = CPM_MAX_READ,
410 .max_write_len = CPM_MAX_READ,
411};
412
413static const struct i2c_adapter cpm_ops = {
414 .owner = THIS_MODULE,
415 .name = "i2c-cpm",
416 .algo = &cpm_i2c_algo,
417 .quirks = &cpm_i2c_quirks,
418};
419
420static int cpm_i2c_setup(struct cpm_i2c *cpm)
421{
422 struct platform_device *ofdev = cpm->ofdev;
423 const u32 *data;
424 int len, ret, i;
425 void __iomem *i2c_base;
426 cbd_t __iomem *tbdf;
427 cbd_t __iomem *rbdf;
428 unsigned char brg;
429
430 dev_dbg(&cpm->ofdev->dev, "cpm_i2c_setup()\n");
431
432 init_waitqueue_head(&cpm->i2c_wait);
433
434 cpm->irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
435 if (!cpm->irq)
436 return -EINVAL;
437
438
439 ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c",
440 &cpm->adap);
441 if (ret)
442 return ret;
443
444
445 i2c_base = of_iomap(ofdev->dev.of_node, 1);
446 if (i2c_base == NULL) {
447 ret = -EINVAL;
448 goto out_irq;
449 }
450
451 if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm1-i2c")) {
452
453
454 cpm->i2c_ram = i2c_base;
455 cpm->i2c_addr = in_be16(&cpm->i2c_ram->rpbase);
456
457
458
459
460
461 if (cpm->i2c_addr) {
462 cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
463 iounmap(i2c_base);
464 }
465
466 cpm->version = 1;
467
468 } else if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm2-i2c")) {
469 cpm->i2c_addr = cpm_muram_alloc(sizeof(struct i2c_ram), 64);
470 cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
471 out_be16(i2c_base, cpm->i2c_addr);
472 iounmap(i2c_base);
473
474 cpm->version = 2;
475
476 } else {
477 iounmap(i2c_base);
478 ret = -EINVAL;
479 goto out_irq;
480 }
481
482
483 cpm->i2c_reg = of_iomap(ofdev->dev.of_node, 0);
484 if (cpm->i2c_reg == NULL) {
485 ret = -EINVAL;
486 goto out_ram;
487 }
488
489 data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
490 if (!data || len != 4) {
491 ret = -EINVAL;
492 goto out_reg;
493 }
494 cpm->cp_command = *data;
495
496 data = of_get_property(ofdev->dev.of_node, "linux,i2c-class", &len);
497 if (data && len == 4)
498 cpm->adap.class = *data;
499
500 data = of_get_property(ofdev->dev.of_node, "clock-frequency", &len);
501 if (data && len == 4)
502 cpm->freq = *data;
503 else
504 cpm->freq = 60000;
505
506
507
508
509
510 cpm->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 2 * CPM_MAXBD, 8);
511 if (!cpm->dp_addr) {
512 ret = -ENOMEM;
513 goto out_reg;
514 }
515
516 cpm->tbase = cpm_muram_addr(cpm->dp_addr);
517 cpm->rbase = cpm_muram_addr(cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD);
518
519
520
521 tbdf = cpm->tbase;
522 rbdf = cpm->rbase;
523
524 for (i = 0; i < CPM_MAXBD; i++) {
525 cpm->rxbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
526 CPM_MAX_READ + 1,
527 &cpm->rxdma[i], GFP_KERNEL);
528 if (!cpm->rxbuf[i]) {
529 ret = -ENOMEM;
530 goto out_muram;
531 }
532 out_be32(&rbdf[i].cbd_bufaddr, ((cpm->rxdma[i] + 1) & ~1));
533
534 cpm->txbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
535 CPM_MAX_READ + 1,
536 &cpm->txdma[i], GFP_KERNEL);
537 if (!cpm->txbuf[i]) {
538 ret = -ENOMEM;
539 goto out_muram;
540 }
541 out_be32(&tbdf[i].cbd_bufaddr, cpm->txdma[i]);
542 }
543
544
545
546 cpm_reset_i2c_params(cpm);
547
548 dev_dbg(&cpm->ofdev->dev, "i2c_ram 0x%p, i2c_addr 0x%04x, freq %d\n",
549 cpm->i2c_ram, cpm->i2c_addr, cpm->freq);
550 dev_dbg(&cpm->ofdev->dev, "tbase 0x%04x, rbase 0x%04x\n",
551 (u8 __iomem *)cpm->tbase - DPRAM_BASE,
552 (u8 __iomem *)cpm->rbase - DPRAM_BASE);
553
554 cpm_command(cpm->cp_command, CPM_CR_INIT_TRX);
555
556
557
558
559 out_8(&cpm->i2c_reg->i2add, 0x7f << 1);
560
561
562
563
564
565
566 brg = get_brgfreq() / (32 * 2 * cpm->freq) - 3;
567 out_8(&cpm->i2c_reg->i2brg, brg);
568
569 out_8(&cpm->i2c_reg->i2mod, 0x00);
570 out_8(&cpm->i2c_reg->i2com, I2COM_MASTER);
571
572
573 out_8(&cpm->i2c_reg->i2cmr, 0);
574 out_8(&cpm->i2c_reg->i2cer, 0xff);
575
576 return 0;
577
578out_muram:
579 for (i = 0; i < CPM_MAXBD; i++) {
580 if (cpm->rxbuf[i])
581 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
582 cpm->rxbuf[i], cpm->rxdma[i]);
583 if (cpm->txbuf[i])
584 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
585 cpm->txbuf[i], cpm->txdma[i]);
586 }
587 cpm_muram_free(cpm->dp_addr);
588out_reg:
589 iounmap(cpm->i2c_reg);
590out_ram:
591 if ((cpm->version == 1) && (!cpm->i2c_addr))
592 iounmap(cpm->i2c_ram);
593 if (cpm->version == 2)
594 cpm_muram_free(cpm->i2c_addr);
595out_irq:
596 free_irq(cpm->irq, &cpm->adap);
597 return ret;
598}
599
600static void cpm_i2c_shutdown(struct cpm_i2c *cpm)
601{
602 int i;
603
604
605 clrbits8(&cpm->i2c_reg->i2mod, I2MOD_EN);
606
607
608 out_8(&cpm->i2c_reg->i2cmr, 0);
609 out_8(&cpm->i2c_reg->i2cer, 0xff);
610
611 free_irq(cpm->irq, &cpm->adap);
612
613
614 for (i = 0; i < CPM_MAXBD; i++) {
615 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
616 cpm->rxbuf[i], cpm->rxdma[i]);
617 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
618 cpm->txbuf[i], cpm->txdma[i]);
619 }
620
621 cpm_muram_free(cpm->dp_addr);
622 iounmap(cpm->i2c_reg);
623
624 if ((cpm->version == 1) && (!cpm->i2c_addr))
625 iounmap(cpm->i2c_ram);
626 if (cpm->version == 2)
627 cpm_muram_free(cpm->i2c_addr);
628}
629
630static int cpm_i2c_probe(struct platform_device *ofdev)
631{
632 int result, len;
633 struct cpm_i2c *cpm;
634 const u32 *data;
635
636 cpm = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL);
637 if (!cpm)
638 return -ENOMEM;
639
640 cpm->ofdev = ofdev;
641
642 platform_set_drvdata(ofdev, cpm);
643
644 cpm->adap = cpm_ops;
645 i2c_set_adapdata(&cpm->adap, cpm);
646 cpm->adap.dev.parent = &ofdev->dev;
647 cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node);
648
649 result = cpm_i2c_setup(cpm);
650 if (result) {
651 dev_err(&ofdev->dev, "Unable to init hardware\n");
652 goto out_free;
653 }
654
655
656
657 data = of_get_property(ofdev->dev.of_node, "linux,i2c-index", &len);
658 cpm->adap.nr = (data && len == 4) ? be32_to_cpup(data) : -1;
659 result = i2c_add_numbered_adapter(&cpm->adap);
660
661 if (result < 0)
662 goto out_shut;
663
664 dev_dbg(&ofdev->dev, "hw routines for %s registered.\n",
665 cpm->adap.name);
666
667 return 0;
668out_shut:
669 cpm_i2c_shutdown(cpm);
670out_free:
671 kfree(cpm);
672
673 return result;
674}
675
676static int cpm_i2c_remove(struct platform_device *ofdev)
677{
678 struct cpm_i2c *cpm = platform_get_drvdata(ofdev);
679
680 i2c_del_adapter(&cpm->adap);
681
682 cpm_i2c_shutdown(cpm);
683
684 kfree(cpm);
685
686 return 0;
687}
688
689static const struct of_device_id cpm_i2c_match[] = {
690 {
691 .compatible = "fsl,cpm1-i2c",
692 },
693 {
694 .compatible = "fsl,cpm2-i2c",
695 },
696 {},
697};
698
699MODULE_DEVICE_TABLE(of, cpm_i2c_match);
700
701static struct platform_driver cpm_i2c_driver = {
702 .probe = cpm_i2c_probe,
703 .remove = cpm_i2c_remove,
704 .driver = {
705 .name = "fsl-i2c-cpm",
706 .of_match_table = cpm_i2c_match,
707 },
708};
709
710module_platform_driver(cpm_i2c_driver);
711
712MODULE_AUTHOR("Jochen Friedrich <jochen@scram.de>");
713MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards");
714MODULE_LICENSE("GPL");
715