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-rw-r--r--drivers/misc/c2port/core.c1003
1 files changed, 1003 insertions, 0 deletions
diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
new file mode 100644
index 000000000000..0207dd59090d
--- /dev/null
+++ b/drivers/misc/c2port/core.c
@@ -0,0 +1,1003 @@
1/*
2 * Silicon Labs C2 port core Linux support
3 *
4 * Copyright (c) 2007 Rodolfo Giometti <giometti@linux.it>
5 * Copyright (c) 2007 Eurotech S.p.A. <info@eurotech.it>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation
10 */
11
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/device.h>
15#include <linux/errno.h>
16#include <linux/err.h>
17#include <linux/kernel.h>
18#include <linux/ctype.h>
19#include <linux/delay.h>
20#include <linux/idr.h>
21#include <linux/sched.h>
22
23#include <linux/c2port.h>
24
25#define DRIVER_NAME "c2port"
26#define DRIVER_VERSION "0.51.0"
27
28static DEFINE_SPINLOCK(c2port_idr_lock);
29static DEFINE_IDR(c2port_idr);
30
31/*
32 * Local variables
33 */
34
35static struct class *c2port_class;
36
37/*
38 * C2 registers & commands defines
39 */
40
41/* C2 registers */
42#define C2PORT_DEVICEID 0x00
43#define C2PORT_REVID 0x01
44#define C2PORT_FPCTL 0x02
45#define C2PORT_FPDAT 0xB4
46
47/* C2 interface commands */
48#define C2PORT_GET_VERSION 0x01
49#define C2PORT_DEVICE_ERASE 0x03
50#define C2PORT_BLOCK_READ 0x06
51#define C2PORT_BLOCK_WRITE 0x07
52#define C2PORT_PAGE_ERASE 0x08
53
54/* C2 status return codes */
55#define C2PORT_INVALID_COMMAND 0x00
56#define C2PORT_COMMAND_FAILED 0x02
57#define C2PORT_COMMAND_OK 0x0d
58
59/*
60 * C2 port low level signal managements
61 */
62
63static void c2port_reset(struct c2port_device *dev)
64{
65 struct c2port_ops *ops = dev->ops;
66
67 /* To reset the device we have to keep clock line low for at least
68 * 20us.
69 */
70 local_irq_disable();
71 ops->c2ck_set(dev, 0);
72 udelay(25);
73 ops->c2ck_set(dev, 1);
74 local_irq_enable();
75
76 udelay(1);
77}
78
79static void c2port_strobe_ck(struct c2port_device *dev)
80{
81 struct c2port_ops *ops = dev->ops;
82
83 /* During hi-low-hi transition we disable local IRQs to avoid
84 * interructions since C2 port specification says that it must be
85 * shorter than 5us, otherwise the microcontroller may consider
86 * it as a reset signal!
87 */
88 local_irq_disable();
89 ops->c2ck_set(dev, 0);
90 udelay(1);
91 ops->c2ck_set(dev, 1);
92 local_irq_enable();
93
94 udelay(1);
95}
96
97/*
98 * C2 port basic functions
99 */
100
101static void c2port_write_ar(struct c2port_device *dev, u8 addr)
102{
103 struct c2port_ops *ops = dev->ops;
104 int i;
105
106 /* START field */
107 c2port_strobe_ck(dev);
108
109 /* INS field (11b, LSB first) */
110 ops->c2d_dir(dev, 0);
111 ops->c2d_set(dev, 1);
112 c2port_strobe_ck(dev);
113 ops->c2d_set(dev, 1);
114 c2port_strobe_ck(dev);
115
116 /* ADDRESS field */
117 for (i = 0; i < 8; i++) {
118 ops->c2d_set(dev, addr & 0x01);
119 c2port_strobe_ck(dev);
120
121 addr >>= 1;
122 }
123
124 /* STOP field */
125 ops->c2d_dir(dev, 1);
126 c2port_strobe_ck(dev);
127}
128
129static int c2port_read_ar(struct c2port_device *dev, u8 *addr)
130{
131 struct c2port_ops *ops = dev->ops;
132 int i;
133
134 /* START field */
135 c2port_strobe_ck(dev);
136
137 /* INS field (10b, LSB first) */
138 ops->c2d_dir(dev, 0);
139 ops->c2d_set(dev, 0);
140 c2port_strobe_ck(dev);
141 ops->c2d_set(dev, 1);
142 c2port_strobe_ck(dev);
143
144 /* ADDRESS field */
145 ops->c2d_dir(dev, 1);
146 *addr = 0;
147 for (i = 0; i < 8; i++) {
148 *addr >>= 1; /* shift in 8-bit ADDRESS field LSB first */
149
150 c2port_strobe_ck(dev);
151 if (ops->c2d_get(dev))
152 *addr |= 0x80;
153 }
154
155 /* STOP field */
156 c2port_strobe_ck(dev);
157
158 return 0;
159}
160
161static int c2port_write_dr(struct c2port_device *dev, u8 data)
162{
163 struct c2port_ops *ops = dev->ops;
164 int timeout, i;
165
166 /* START field */
167 c2port_strobe_ck(dev);
168
169 /* INS field (01b, LSB first) */
170 ops->c2d_dir(dev, 0);
171 ops->c2d_set(dev, 1);
172 c2port_strobe_ck(dev);
173 ops->c2d_set(dev, 0);
174 c2port_strobe_ck(dev);
175
176 /* LENGTH field (00b, LSB first -> 1 byte) */
177 ops->c2d_set(dev, 0);
178 c2port_strobe_ck(dev);
179 ops->c2d_set(dev, 0);
180 c2port_strobe_ck(dev);
181
182 /* DATA field */
183 for (i = 0; i < 8; i++) {
184 ops->c2d_set(dev, data & 0x01);
185 c2port_strobe_ck(dev);
186
187 data >>= 1;
188 }
189
190 /* WAIT field */
191 ops->c2d_dir(dev, 1);
192 timeout = 20;
193 do {
194 c2port_strobe_ck(dev);
195 if (ops->c2d_get(dev))
196 break;
197
198 udelay(1);
199 } while (--timeout > 0);
200 if (timeout == 0)
201 return -EIO;
202
203 /* STOP field */
204 c2port_strobe_ck(dev);
205
206 return 0;
207}
208
209static int c2port_read_dr(struct c2port_device *dev, u8 *data)
210{
211 struct c2port_ops *ops = dev->ops;
212 int timeout, i;
213
214 /* START field */
215 c2port_strobe_ck(dev);
216
217 /* INS field (00b, LSB first) */
218 ops->c2d_dir(dev, 0);
219 ops->c2d_set(dev, 0);
220 c2port_strobe_ck(dev);
221 ops->c2d_set(dev, 0);
222 c2port_strobe_ck(dev);
223
224 /* LENGTH field (00b, LSB first -> 1 byte) */
225 ops->c2d_set(dev, 0);
226 c2port_strobe_ck(dev);
227 ops->c2d_set(dev, 0);
228 c2port_strobe_ck(dev);
229
230 /* WAIT field */
231 ops->c2d_dir(dev, 1);
232 timeout = 20;
233 do {
234 c2port_strobe_ck(dev);
235 if (ops->c2d_get(dev))
236 break;
237
238 udelay(1);
239 } while (--timeout > 0);
240 if (timeout == 0)
241 return -EIO;
242
243 /* DATA field */
244 *data = 0;
245 for (i = 0; i < 8; i++) {
246 *data >>= 1; /* shift in 8-bit DATA field LSB first */
247
248 c2port_strobe_ck(dev);
249 if (ops->c2d_get(dev))
250 *data |= 0x80;
251 }
252
253 /* STOP field */
254 c2port_strobe_ck(dev);
255
256 return 0;
257}
258
259static int c2port_poll_in_busy(struct c2port_device *dev)
260{
261 u8 addr;
262 int ret, timeout = 20;
263
264 do {
265 ret = (c2port_read_ar(dev, &addr));
266 if (ret < 0)
267 return -EIO;
268
269 if (!(addr & 0x02))
270 break;
271
272 udelay(1);
273 } while (--timeout > 0);
274 if (timeout == 0)
275 return -EIO;
276
277 return 0;
278}
279
280static int c2port_poll_out_ready(struct c2port_device *dev)
281{
282 u8 addr;
283 int ret, timeout = 10000; /* erase flash needs long time... */
284
285 do {
286 ret = (c2port_read_ar(dev, &addr));
287 if (ret < 0)
288 return -EIO;
289
290 if (addr & 0x01)
291 break;
292
293 udelay(1);
294 } while (--timeout > 0);
295 if (timeout == 0)
296 return -EIO;
297
298 return 0;
299}
300
301/*
302 * sysfs methods
303 */
304
305static ssize_t c2port_show_name(struct device *dev,
306 struct device_attribute *attr, char *buf)
307{
308 struct c2port_device *c2dev = dev_get_drvdata(dev);
309
310 return sprintf(buf, "%s\n", c2dev->name);
311}
312
313static ssize_t c2port_show_flash_blocks_num(struct device *dev,
314 struct device_attribute *attr, char *buf)
315{
316 struct c2port_device *c2dev = dev_get_drvdata(dev);
317 struct c2port_ops *ops = c2dev->ops;
318
319 return sprintf(buf, "%d\n", ops->blocks_num);
320}
321
322static ssize_t c2port_show_flash_block_size(struct device *dev,
323 struct device_attribute *attr, char *buf)
324{
325 struct c2port_device *c2dev = dev_get_drvdata(dev);
326 struct c2port_ops *ops = c2dev->ops;
327
328 return sprintf(buf, "%d\n", ops->block_size);
329}
330
331static ssize_t c2port_show_flash_size(struct device *dev,
332 struct device_attribute *attr, char *buf)
333{
334 struct c2port_device *c2dev = dev_get_drvdata(dev);
335 struct c2port_ops *ops = c2dev->ops;
336
337 return sprintf(buf, "%d\n", ops->blocks_num * ops->block_size);
338}
339
340static ssize_t c2port_show_access(struct device *dev,
341 struct device_attribute *attr, char *buf)
342{
343 struct c2port_device *c2dev = dev_get_drvdata(dev);
344
345 return sprintf(buf, "%d\n", c2dev->access);
346}
347
348static ssize_t c2port_store_access(struct device *dev,
349 struct device_attribute *attr,
350 const char *buf, size_t count)
351{
352 struct c2port_device *c2dev = dev_get_drvdata(dev);
353 struct c2port_ops *ops = c2dev->ops;
354 int status, ret;
355
356 ret = sscanf(buf, "%d", &status);
357 if (ret != 1)
358 return -EINVAL;
359
360 mutex_lock(&c2dev->mutex);
361
362 c2dev->access = !!status;
363
364 /* If access is "on" clock should be HIGH _before_ setting the line
365 * as output and data line should be set as INPUT anyway */
366 if (c2dev->access)
367 ops->c2ck_set(c2dev, 1);
368 ops->access(c2dev, c2dev->access);
369 if (c2dev->access)
370 ops->c2d_dir(c2dev, 1);
371
372 mutex_unlock(&c2dev->mutex);
373
374 return count;
375}
376
377static ssize_t c2port_store_reset(struct device *dev,
378 struct device_attribute *attr,
379 const char *buf, size_t count)
380{
381 struct c2port_device *c2dev = dev_get_drvdata(dev);
382
383 /* Check the device access status */
384 if (!c2dev->access)
385 return -EBUSY;
386
387 mutex_lock(&c2dev->mutex);
388
389 c2port_reset(c2dev);
390 c2dev->flash_access = 0;
391
392 mutex_unlock(&c2dev->mutex);
393
394 return count;
395}
396
397static ssize_t __c2port_show_dev_id(struct c2port_device *dev, char *buf)
398{
399 u8 data;
400 int ret;
401
402 /* Select DEVICEID register for C2 data register accesses */
403 c2port_write_ar(dev, C2PORT_DEVICEID);
404
405 /* Read and return the device ID register */
406 ret = c2port_read_dr(dev, &data);
407 if (ret < 0)
408 return ret;
409
410 return sprintf(buf, "%d\n", data);
411}
412
413static ssize_t c2port_show_dev_id(struct device *dev,
414 struct device_attribute *attr, char *buf)
415{
416 struct c2port_device *c2dev = dev_get_drvdata(dev);
417 ssize_t ret;
418
419 /* Check the device access status */
420 if (!c2dev->access)
421 return -EBUSY;
422
423 mutex_lock(&c2dev->mutex);
424 ret = __c2port_show_dev_id(c2dev, buf);
425 mutex_unlock(&c2dev->mutex);
426
427 if (ret < 0)
428 dev_err(dev, "cannot read from %s\n", c2dev->name);
429
430 return ret;
431}
432
433static ssize_t __c2port_show_rev_id(struct c2port_device *dev, char *buf)
434{
435 u8 data;
436 int ret;
437
438 /* Select REVID register for C2 data register accesses */
439 c2port_write_ar(dev, C2PORT_REVID);
440
441 /* Read and return the revision ID register */
442 ret = c2port_read_dr(dev, &data);
443 if (ret < 0)
444 return ret;
445
446 return sprintf(buf, "%d\n", data);
447}
448
449static ssize_t c2port_show_rev_id(struct device *dev,
450 struct device_attribute *attr, char *buf)
451{
452 struct c2port_device *c2dev = dev_get_drvdata(dev);
453 ssize_t ret;
454
455 /* Check the device access status */
456 if (!c2dev->access)
457 return -EBUSY;
458
459 mutex_lock(&c2dev->mutex);
460 ret = __c2port_show_rev_id(c2dev, buf);
461 mutex_unlock(&c2dev->mutex);
462
463 if (ret < 0)
464 dev_err(c2dev->dev, "cannot read from %s\n", c2dev->name);
465
466 return ret;
467}
468
469static ssize_t c2port_show_flash_access(struct device *dev,
470 struct device_attribute *attr, char *buf)
471{
472 struct c2port_device *c2dev = dev_get_drvdata(dev);
473
474 return sprintf(buf, "%d\n", c2dev->flash_access);
475}
476
477static ssize_t __c2port_store_flash_access(struct c2port_device *dev,
478 int status)
479{
480 int ret;
481
482 /* Check the device access status */
483 if (!dev->access)
484 return -EBUSY;
485
486 dev->flash_access = !!status;
487
488 /* If flash_access is off we have nothing to do... */
489 if (dev->flash_access == 0)
490 return 0;
491
492 /* Target the C2 flash programming control register for C2 data
493 * register access */
494 c2port_write_ar(dev, C2PORT_FPCTL);
495
496 /* Write the first keycode to enable C2 Flash programming */
497 ret = c2port_write_dr(dev, 0x02);
498 if (ret < 0)
499 return ret;
500
501 /* Write the second keycode to enable C2 Flash programming */
502 ret = c2port_write_dr(dev, 0x01);
503 if (ret < 0)
504 return ret;
505
506 /* Delay for at least 20ms to ensure the target is ready for
507 * C2 flash programming */
508 mdelay(25);
509
510 return 0;
511}
512
513static ssize_t c2port_store_flash_access(struct device *dev,
514 struct device_attribute *attr,
515 const char *buf, size_t count)
516{
517 struct c2port_device *c2dev = dev_get_drvdata(dev);
518 int status;
519 ssize_t ret;
520
521 ret = sscanf(buf, "%d", &status);
522 if (ret != 1)
523 return -EINVAL;
524
525 mutex_lock(&c2dev->mutex);
526 ret = __c2port_store_flash_access(c2dev, status);
527 mutex_unlock(&c2dev->mutex);
528
529 if (ret < 0) {
530 dev_err(c2dev->dev, "cannot enable %s flash programming\n",
531 c2dev->name);
532 return ret;
533 }
534
535 return count;
536}
537
538static ssize_t __c2port_write_flash_erase(struct c2port_device *dev)
539{
540 u8 status;
541 int ret;
542
543 /* Target the C2 flash programming data register for C2 data register
544 * access.
545 */
546 c2port_write_ar(dev, C2PORT_FPDAT);
547
548 /* Send device erase command */
549 c2port_write_dr(dev, C2PORT_DEVICE_ERASE);
550
551 /* Wait for input acknowledge */
552 ret = c2port_poll_in_busy(dev);
553 if (ret < 0)
554 return ret;
555
556 /* Should check status before starting FLASH access sequence */
557
558 /* Wait for status information */
559 ret = c2port_poll_out_ready(dev);
560 if (ret < 0)
561 return ret;
562
563 /* Read flash programming interface status */
564 ret = c2port_read_dr(dev, &status);
565 if (ret < 0)
566 return ret;
567 if (status != C2PORT_COMMAND_OK)
568 return -EBUSY;
569
570 /* Send a three-byte arming sequence to enable the device erase.
571 * If the sequence is not received correctly, the command will be
572 * ignored.
573 * Sequence is: 0xde, 0xad, 0xa5.
574 */
575 c2port_write_dr(dev, 0xde);
576 ret = c2port_poll_in_busy(dev);
577 if (ret < 0)
578 return ret;
579 c2port_write_dr(dev, 0xad);
580 ret = c2port_poll_in_busy(dev);
581 if (ret < 0)
582 return ret;
583 c2port_write_dr(dev, 0xa5);
584 ret = c2port_poll_in_busy(dev);
585 if (ret < 0)
586 return ret;
587
588 ret = c2port_poll_out_ready(dev);
589 if (ret < 0)
590 return ret;
591
592 return 0;
593}
594
595static ssize_t c2port_store_flash_erase(struct device *dev,
596 struct device_attribute *attr,
597 const char *buf, size_t count)
598{
599 struct c2port_device *c2dev = dev_get_drvdata(dev);
600 int ret;
601
602 /* Check the device and flash access status */
603 if (!c2dev->access || !c2dev->flash_access)
604 return -EBUSY;
605
606 mutex_lock(&c2dev->mutex);
607 ret = __c2port_write_flash_erase(c2dev);
608 mutex_unlock(&c2dev->mutex);
609
610 if (ret < 0) {
611 dev_err(c2dev->dev, "cannot erase %s flash\n", c2dev->name);
612 return ret;
613 }
614
615 return count;
616}
617
618static ssize_t __c2port_read_flash_data(struct c2port_device *dev,
619 char *buffer, loff_t offset, size_t count)
620{
621 struct c2port_ops *ops = dev->ops;
622 u8 status, nread = 128;
623 int i, ret;
624
625 /* Check for flash end */
626 if (offset >= ops->block_size * ops->blocks_num)
627 return 0;
628
629 if (ops->block_size * ops->blocks_num - offset < nread)
630 nread = ops->block_size * ops->blocks_num - offset;
631 if (count < nread)
632 nread = count;
633 if (nread == 0)
634 return nread;
635
636 /* Target the C2 flash programming data register for C2 data register
637 * access */
638 c2port_write_ar(dev, C2PORT_FPDAT);
639
640 /* Send flash block read command */
641 c2port_write_dr(dev, C2PORT_BLOCK_READ);
642
643 /* Wait for input acknowledge */
644 ret = c2port_poll_in_busy(dev);
645 if (ret < 0)
646 return ret;
647
648 /* Should check status before starting FLASH access sequence */
649
650 /* Wait for status information */
651 ret = c2port_poll_out_ready(dev);
652 if (ret < 0)
653 return ret;
654
655 /* Read flash programming interface status */
656 ret = c2port_read_dr(dev, &status);
657 if (ret < 0)
658 return ret;
659 if (status != C2PORT_COMMAND_OK)
660 return -EBUSY;
661
662 /* Send address high byte */
663 c2port_write_dr(dev, offset >> 8);
664 ret = c2port_poll_in_busy(dev);
665 if (ret < 0)
666 return ret;
667
668 /* Send address low byte */
669 c2port_write_dr(dev, offset & 0x00ff);
670 ret = c2port_poll_in_busy(dev);
671 if (ret < 0)
672 return ret;
673
674 /* Send address block size */
675 c2port_write_dr(dev, nread);
676 ret = c2port_poll_in_busy(dev);
677 if (ret < 0)
678 return ret;
679
680 /* Should check status before reading FLASH block */
681
682 /* Wait for status information */
683 ret = c2port_poll_out_ready(dev);
684 if (ret < 0)
685 return ret;
686
687 /* Read flash programming interface status */
688 ret = c2port_read_dr(dev, &status);
689 if (ret < 0)
690 return ret;
691 if (status != C2PORT_COMMAND_OK)
692 return -EBUSY;
693
694 /* Read flash block */
695 for (i = 0; i < nread; i++) {
696 ret = c2port_poll_out_ready(dev);
697 if (ret < 0)
698 return ret;
699
700 ret = c2port_read_dr(dev, buffer+i);
701 if (ret < 0)
702 return ret;
703 }
704
705 return nread;
706}
707
708static ssize_t c2port_read_flash_data(struct kobject *kobj,
709 struct bin_attribute *attr,
710 char *buffer, loff_t offset, size_t count)
711{
712 struct c2port_device *c2dev =
713 dev_get_drvdata(container_of(kobj,
714 struct device, kobj));
715 ssize_t ret;
716
717 /* Check the device and flash access status */
718 if (!c2dev->access || !c2dev->flash_access)
719 return -EBUSY;
720
721 mutex_lock(&c2dev->mutex);
722 ret = __c2port_read_flash_data(c2dev, buffer, offset, count);
723 mutex_unlock(&c2dev->mutex);
724
725 if (ret < 0)
726 dev_err(c2dev->dev, "cannot read %s flash\n", c2dev->name);
727
728 return ret;
729}
730
731static ssize_t __c2port_write_flash_data(struct c2port_device *dev,
732 char *buffer, loff_t offset, size_t count)
733{
734 struct c2port_ops *ops = dev->ops;
735 u8 status, nwrite = 128;
736 int i, ret;
737
738 if (nwrite > count)
739 nwrite = count;
740 if (ops->block_size * ops->blocks_num - offset < nwrite)
741 nwrite = ops->block_size * ops->blocks_num - offset;
742
743 /* Check for flash end */
744 if (offset >= ops->block_size * ops->blocks_num)
745 return -EINVAL;
746
747 /* Target the C2 flash programming data register for C2 data register
748 * access */
749 c2port_write_ar(dev, C2PORT_FPDAT);
750
751 /* Send flash block write command */
752 c2port_write_dr(dev, C2PORT_BLOCK_WRITE);
753
754 /* Wait for input acknowledge */
755 ret = c2port_poll_in_busy(dev);
756 if (ret < 0)
757 return ret;
758
759 /* Should check status before starting FLASH access sequence */
760
761 /* Wait for status information */
762 ret = c2port_poll_out_ready(dev);
763 if (ret < 0)
764 return ret;
765
766 /* Read flash programming interface status */
767 ret = c2port_read_dr(dev, &status);
768 if (ret < 0)
769 return ret;
770 if (status != C2PORT_COMMAND_OK)
771 return -EBUSY;
772
773 /* Send address high byte */
774 c2port_write_dr(dev, offset >> 8);
775 ret = c2port_poll_in_busy(dev);
776 if (ret < 0)
777 return ret;
778
779 /* Send address low byte */
780 c2port_write_dr(dev, offset & 0x00ff);
781 ret = c2port_poll_in_busy(dev);
782 if (ret < 0)
783 return ret;
784
785 /* Send address block size */
786 c2port_write_dr(dev, nwrite);
787 ret = c2port_poll_in_busy(dev);
788 if (ret < 0)
789 return ret;
790
791 /* Should check status before writing FLASH block */
792
793 /* Wait for status information */
794 ret = c2port_poll_out_ready(dev);
795 if (ret < 0)
796 return ret;
797
798 /* Read flash programming interface status */
799 ret = c2port_read_dr(dev, &status);
800 if (ret < 0)
801 return ret;
802 if (status != C2PORT_COMMAND_OK)
803 return -EBUSY;
804
805 /* Write flash block */
806 for (i = 0; i < nwrite; i++) {
807 ret = c2port_write_dr(dev, *(buffer+i));
808 if (ret < 0)
809 return ret;
810
811 ret = c2port_poll_in_busy(dev);
812 if (ret < 0)
813 return ret;
814
815 }
816
817 /* Wait for last flash write to complete */
818 ret = c2port_poll_out_ready(dev);
819 if (ret < 0)
820 return ret;
821
822 return nwrite;
823}
824
825static ssize_t c2port_write_flash_data(struct kobject *kobj,
826 struct bin_attribute *attr,
827 char *buffer, loff_t offset, size_t count)
828{
829 struct c2port_device *c2dev =
830 dev_get_drvdata(container_of(kobj,
831 struct device, kobj));
832 int ret;
833
834 /* Check the device access status */
835 if (!c2dev->access || !c2dev->flash_access)
836 return -EBUSY;
837
838 mutex_lock(&c2dev->mutex);
839 ret = __c2port_write_flash_data(c2dev, buffer, offset, count);
840 mutex_unlock(&c2dev->mutex);
841
842 if (ret < 0)
843 dev_err(c2dev->dev, "cannot write %s flash\n", c2dev->name);
844
845 return ret;
846}
847
848/*
849 * Class attributes
850 */
851
852static struct device_attribute c2port_attrs[] = {
853 __ATTR(name, 0444, c2port_show_name, NULL),
854 __ATTR(flash_blocks_num, 0444, c2port_show_flash_blocks_num, NULL),
855 __ATTR(flash_block_size, 0444, c2port_show_flash_block_size, NULL),
856 __ATTR(flash_size, 0444, c2port_show_flash_size, NULL),
857 __ATTR(access, 0644, c2port_show_access, c2port_store_access),
858 __ATTR(reset, 0200, NULL, c2port_store_reset),
859 __ATTR(dev_id, 0444, c2port_show_dev_id, NULL),
860 __ATTR(rev_id, 0444, c2port_show_rev_id, NULL),
861
862 __ATTR(flash_access, 0644, c2port_show_flash_access,
863 c2port_store_flash_access),
864 __ATTR(flash_erase, 0200, NULL, c2port_store_flash_erase),
865 __ATTR_NULL,
866};
867
868static struct bin_attribute c2port_bin_attrs = {
869 .attr = {
870 .name = "flash_data",
871 .mode = 0644
872 },
873 .read = c2port_read_flash_data,
874 .write = c2port_write_flash_data,
875 /* .size is computed at run-time */
876};
877
878/*
879 * Exported functions
880 */
881
882struct c2port_device *c2port_device_register(char *name,
883 struct c2port_ops *ops, void *devdata)
884{
885 struct c2port_device *c2dev;
886 int id, ret;
887
888 if (unlikely(!ops) || unlikely(!ops->access) || \
889 unlikely(!ops->c2d_dir) || unlikely(!ops->c2ck_set) || \
890 unlikely(!ops->c2d_get) || unlikely(!ops->c2d_set))
891 return ERR_PTR(-EINVAL);
892
893 c2dev = kmalloc(sizeof(struct c2port_device), GFP_KERNEL);
894 if (unlikely(!c2dev))
895 return ERR_PTR(-ENOMEM);
896
897 ret = idr_pre_get(&c2port_idr, GFP_KERNEL);
898 if (!ret) {
899 ret = -ENOMEM;
900 goto error_idr_get_new;
901 }
902
903 spin_lock_irq(&c2port_idr_lock);
904 ret = idr_get_new(&c2port_idr, c2dev, &id);
905 spin_unlock_irq(&c2port_idr_lock);
906
907 if (ret < 0)
908 goto error_idr_get_new;
909 c2dev->id = id;
910
911 c2dev->dev = device_create(c2port_class, NULL, 0, c2dev,
912 "c2port%d", id);
913 if (unlikely(!c2dev->dev)) {
914 ret = -ENOMEM;
915 goto error_device_create;
916 }
917 dev_set_drvdata(c2dev->dev, c2dev);
918
919 strncpy(c2dev->name, name, C2PORT_NAME_LEN);
920 c2dev->ops = ops;
921 mutex_init(&c2dev->mutex);
922
923 /* Create binary file */
924 c2port_bin_attrs.size = ops->blocks_num * ops->block_size;
925 ret = device_create_bin_file(c2dev->dev, &c2port_bin_attrs);
926 if (unlikely(ret))
927 goto error_device_create_bin_file;
928
929 /* By default C2 port access is off */
930 c2dev->access = c2dev->flash_access = 0;
931 ops->access(c2dev, 0);
932
933 dev_info(c2dev->dev, "C2 port %s added\n", name);
934 dev_info(c2dev->dev, "%s flash has %d blocks x %d bytes "
935 "(%d bytes total)\n",
936 name, ops->blocks_num, ops->block_size,
937 ops->blocks_num * ops->block_size);
938
939 return c2dev;
940
941error_device_create_bin_file:
942 device_destroy(c2port_class, 0);
943
944error_device_create:
945 spin_lock_irq(&c2port_idr_lock);
946 idr_remove(&c2port_idr, id);
947 spin_unlock_irq(&c2port_idr_lock);
948
949error_idr_get_new:
950 kfree(c2dev);
951
952 return ERR_PTR(ret);
953}
954EXPORT_SYMBOL(c2port_device_register);
955
956void c2port_device_unregister(struct c2port_device *c2dev)
957{
958 if (!c2dev)
959 return;
960
961 dev_info(c2dev->dev, "C2 port %s removed\n", c2dev->name);
962
963 device_remove_bin_file(c2dev->dev, &c2port_bin_attrs);
964 spin_lock_irq(&c2port_idr_lock);
965 idr_remove(&c2port_idr, c2dev->id);
966 spin_unlock_irq(&c2port_idr_lock);
967
968 device_destroy(c2port_class, c2dev->id);
969
970 kfree(c2dev);
971}
972EXPORT_SYMBOL(c2port_device_unregister);
973
974/*
975 * Module stuff
976 */
977
978static int __init c2port_init(void)
979{
980 printk(KERN_INFO "Silicon Labs C2 port support v. " DRIVER_VERSION
981 " - (C) 2007 Rodolfo Giometti\n");
982
983 c2port_class = class_create(THIS_MODULE, "c2port");
984 if (!c2port_class) {
985 printk(KERN_ERR "c2port: failed to allocate class\n");
986 return -ENOMEM;
987 }
988 c2port_class->dev_attrs = c2port_attrs;
989
990 return 0;
991}
992
993static void __exit c2port_exit(void)
994{
995 class_destroy(c2port_class);
996}
997
998module_init(c2port_init);
999module_exit(c2port_exit);
1000
1001MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1002MODULE_DESCRIPTION("Silicon Labs C2 port support v. " DRIVER_VERSION);
1003MODULE_LICENSE("GPL");