summaryrefslogtreecommitdiffstats
path: root/drivers/misc/ti-st/st_kim.c
blob: 9ff942a346edb59ff05d3a3fec52f052ab8849bb (plain)
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
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
/*
 *  Shared Transport Line discipline driver Core
 *	Init Manager module responsible for GPIO control
 *	and firmware download
 *  Copyright (C) 2009-2010 Texas Instruments
 *  Author: Pavan Savoy <pavan_savoy@ti.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#define pr_fmt(fmt) "(stk) :" fmt
#include <linux/platform_device.h>
#include <linux/jiffies.h>
#include <linux/firmware.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/gpio.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/sched.h>
#include <linux/sysfs.h>
#include <linux/tty.h>

#include <linux/skbuff.h>
#include <linux/ti_wilink_st.h>
#include <linux/module.h>


#define MAX_ST_DEVICES	3	/* Imagine 1 on each UART for now */
static struct platform_device *st_kim_devices[MAX_ST_DEVICES];

/**********************************************************************/
/* internal functions */

/**
 * st_get_plat_device -
 *	function which returns the reference to the platform device
 *	requested by id. As of now only 1 such device exists (id=0)
 *	the context requesting for reference can get the id to be
 *	requested by a. The protocol driver which is registering or
 *	b. the tty device which is opened.
 */
static struct platform_device *st_get_plat_device(int id)
{
	return st_kim_devices[id];
}

/**
 * validate_firmware_response -
 *	function to return whether the firmware response was proper
 *	in case of error don't complete so that waiting for proper
 *	response times out
 */
static void validate_firmware_response(struct kim_data_s *kim_gdata)
{
	struct sk_buff *skb = kim_gdata->rx_skb;
	if (!skb)
		return;

	/* these magic numbers are the position in the response buffer which
	 * allows us to distinguish whether the response is for the read
	 * version info. command
	 */
	if (skb->data[2] == 0x01 && skb->data[3] == 0x01 &&
			skb->data[4] == 0x10 && skb->data[5] == 0x00) {
		/* fw version response */
		memcpy(kim_gdata->resp_buffer,
				kim_gdata->rx_skb->data,
				kim_gdata->rx_skb->len);
		complete_all(&kim_gdata->kim_rcvd);
		kim_gdata->rx_state = ST_W4_PACKET_TYPE;
		kim_gdata->rx_skb = NULL;
		kim_gdata->rx_count = 0;
	} else if (unlikely(skb->data[5] != 0)) {
		pr_err("no proper response during fw download");
		pr_err("data6 %x", skb->data[5]);
		kfree_skb(skb);
		return;		/* keep waiting for the proper response */
	}
	/* becos of all the script being downloaded */
	complete_all(&kim_gdata->kim_rcvd);
	kfree_skb(skb);
}

/* check for data len received inside kim_int_recv
 * most often hit the last case to update state to waiting for data
 */
static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
{
	register int room = skb_tailroom(kim_gdata->rx_skb);

	pr_debug("len %d room %d", len, room);

	if (!len) {
		validate_firmware_response(kim_gdata);
	} else if (len > room) {
		/* Received packet's payload length is larger.
		 * We can't accommodate it in created skb.
		 */
		pr_err("Data length is too large len %d room %d", len,
			   room);
		kfree_skb(kim_gdata->rx_skb);
	} else {
		/* Packet header has non-zero payload length and
		 * we have enough space in created skb. Lets read
		 * payload data */
		kim_gdata->rx_state = ST_W4_DATA;
		kim_gdata->rx_count = len;
		return len;
	}

	/* Change ST LL state to continue to process next
	 * packet */
	kim_gdata->rx_state = ST_W4_PACKET_TYPE;
	kim_gdata->rx_skb = NULL;
	kim_gdata->rx_count = 0;

	return 0;
}

/**
 * kim_int_recv - receive function called during firmware download
 *	firmware download responses on different UART drivers
 *	have been observed to come in bursts of different
 *	tty_receive and hence the logic
 */
static void kim_int_recv(struct kim_data_s *kim_gdata,
	const unsigned char *data, long count)
{
	const unsigned char *ptr;
	int len = 0, type = 0;
	unsigned char *plen;

	pr_debug("%s", __func__);
	/* Decode received bytes here */
	ptr = data;
	if (unlikely(ptr == NULL)) {
		pr_err(" received null from TTY ");
		return;
	}

	while (count) {
		if (kim_gdata->rx_count) {
			len = min_t(unsigned int, kim_gdata->rx_count, count);
			memcpy(skb_put(kim_gdata->rx_skb, len), ptr, len);
			kim_gdata->rx_count -= len;
			count -= len;
			ptr += len;

			if (kim_gdata->rx_count)
				continue;

			/* Check ST RX state machine , where are we? */
			switch (kim_gdata->rx_state) {
				/* Waiting for complete packet ? */
			case ST_W4_DATA:
				pr_debug("Complete pkt received");
				validate_firmware_response(kim_gdata);
				kim_gdata->rx_state = ST_W4_PACKET_TYPE;
				kim_gdata->rx_skb = NULL;
				continue;
				/* Waiting for Bluetooth event header ? */
			case ST_W4_HEADER:
				plen =
				(unsigned char *)&kim_gdata->rx_skb->data[1];
				pr_debug("event hdr: plen 0x%02x\n", *plen);
				kim_check_data_len(kim_gdata, *plen);
				continue;
			}	/* end of switch */
		}		/* end of if rx_state */
		switch (*ptr) {
			/* Bluetooth event packet? */
		case 0x04:
			kim_gdata->rx_state = ST_W4_HEADER;
			kim_gdata->rx_count = 2;
			type = *ptr;
			break;
		default:
			pr_info("unknown packet");
			ptr++;
			count--;
			continue;
		}
		ptr++;
		count--;
		kim_gdata->rx_skb =
			alloc_skb(1024+8, GFP_ATOMIC);
		if (!kim_gdata->rx_skb) {
			pr_err("can't allocate mem for new packet");
			kim_gdata->rx_state = ST_W4_PACKET_TYPE;
			kim_gdata->rx_count = 0;
			return;
		}
		skb_reserve(kim_gdata->rx_skb, 8);
		kim_gdata->rx_skb->cb[0] = 4;
		kim_gdata->rx_skb->cb[1] = 0;

	}
	return;
}

static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
{
	unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
	const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };

	pr_debug("%s", __func__);

	INIT_COMPLETION(kim_gdata->kim_rcvd);
	if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
		pr_err("kim: couldn't write 4 bytes");
		return -EIO;
	}

	if (!wait_for_completion_interruptible_timeout(
		&kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME))) {
		pr_err(" waiting for ver info- timed out ");
		return -ETIMEDOUT;
	}
	INIT_COMPLETION(kim_gdata->kim_rcvd);
	/* the positions 12 & 13 in the response buffer provide with the
	 * chip, major & minor numbers
	 */

	version =
		MAKEWORD(kim_gdata->resp_buffer[12],
				kim_gdata->resp_buffer[13]);
	chip = (version & 0x7C00) >> 10;
	min_ver = (version & 0x007F);
	maj_ver = (version & 0x0380) >> 7;

	if (version & 0x8000)
		maj_ver |= 0x0008;

	sprintf(bts_scr_name, "TIInit_%d.%d.%d.bts", chip, maj_ver, min_ver);

	/* to be accessed later via sysfs entry */
	kim_gdata->version.full = version;
	kim_gdata->version.chip = chip;
	kim_gdata->version.maj_ver = maj_ver;
	kim_gdata->version.min_ver = min_ver;

	pr_info("%s", bts_scr_name);
	return 0;
}

static void skip_change_remote_baud(unsigned char **ptr, long *len)
{
	unsigned char *nxt_action, *cur_action;
	cur_action = *ptr;

	nxt_action = cur_action + sizeof(struct bts_action) +
		((struct bts_action *) cur_action)->size;

	if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
		pr_err("invalid action after change remote baud command");
	} else {
		*ptr = *ptr + sizeof(struct bts_action) +
			((struct bts_action *)cur_action)->size;
		*len = *len - (sizeof(struct bts_action) +
				((struct bts_action *)cur_action)->size);
		/* warn user on not commenting these in firmware */
		pr_warn("skipping the wait event of change remote baud");
	}
}

/**
 * download_firmware -
 *	internal function which parses through the .bts firmware
 *	script file intreprets SEND, DELAY actions only as of now
 */
static long download_firmware(struct kim_data_s *kim_gdata)
{
	long err = 0;
	long len = 0;
	unsigned char *ptr = NULL;
	unsigned char *action_ptr = NULL;
	unsigned char bts_scr_name[30] = { 0 };	/* 30 char long bts scr name? */
	int wr_room_space;
	int cmd_size;
	unsigned long timeout;

	err = read_local_version(kim_gdata, bts_scr_name);
	if (err != 0) {
		pr_err("kim: failed to read local ver");
		return err;
	}
	err =
	    request_firmware(&kim_gdata->fw_entry, bts_scr_name,
			     &kim_gdata->kim_pdev->dev);
	if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
		     (kim_gdata->fw_entry->size == 0))) {
		pr_err(" request_firmware failed(errno %ld) for %s", err,
			   bts_scr_name);
		return -EINVAL;
	}
	ptr = (void *)kim_gdata->fw_entry->data;
	len = kim_gdata->fw_entry->size;
	/* bts_header to remove out magic number and
	 * version
	 */
	ptr += sizeof(struct bts_header);
	len -= sizeof(struct bts_header);

	while (len > 0 && ptr) {
		pr_debug(" action size %d, type %d ",
			   ((struct bts_action *)ptr)->size,
			   ((struct bts_action *)ptr)->type);

		switch (((struct bts_action *)ptr)->type) {
		case ACTION_SEND_COMMAND:	/* action send */
			pr_debug("S");
			action_ptr = &(((struct bts_action *)ptr)->data[0]);
			if (unlikely
			    (((struct hci_command *)action_ptr)->opcode ==
			     0xFF36)) {
				/* ignore remote change
				 * baud rate HCI VS command */
				pr_warn("change remote baud"
				    " rate command in firmware");
				skip_change_remote_baud(&ptr, &len);
				break;
			}
			/*
			 * Make sure we have enough free space in uart
			 * tx buffer to write current firmware command
			 */
			cmd_size = ((struct bts_action *)ptr)->size;
			timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
			do {
				wr_room_space =
					st_get_uart_wr_room(kim_gdata->core_data);
				if (wr_room_space < 0) {
					pr_err("Unable to get free "
							"space info from uart tx buffer");
					release_firmware(kim_gdata->fw_entry);
					return wr_room_space;
				}
				mdelay(1); /* wait 1ms before checking room */
			} while ((wr_room_space < cmd_size) &&
					time_before(jiffies, timeout));

			/* Timeout happened ? */
			if (time_after_eq(jiffies, timeout)) {
				pr_err("Timeout while waiting for free "
						"free space in uart tx buffer");
				release_firmware(kim_gdata->fw_entry);
				return -ETIMEDOUT;
			}
			/* reinit completion before sending for the
			 * relevant wait
			 */
			INIT_COMPLETION(kim_gdata->kim_rcvd);

			/*
			 * Free space found in uart buffer, call st_int_write
			 * to send current firmware command to the uart tx
			 * buffer.
			 */
			err = st_int_write(kim_gdata->core_data,
			((struct bts_action_send *)action_ptr)->data,
					   ((struct bts_action *)ptr)->size);
			if (unlikely(err < 0)) {
				release_firmware(kim_gdata->fw_entry);
				return err;
			}
			/*
			 * Check number of bytes written to the uart tx buffer
			 * and requested command write size
			 */
			if (err != cmd_size) {
				pr_err("Number of bytes written to uart "
						"tx buffer are not matching with "
						"requested cmd write size");
				release_firmware(kim_gdata->fw_entry);
				return -EIO;
			}
			break;
		case ACTION_WAIT_EVENT:  /* wait */
			pr_debug("W");
			if (!wait_for_completion_interruptible_timeout(
					&kim_gdata->kim_rcvd,
					msecs_to_jiffies(CMD_RESP_TIME))) {
				pr_err("response timeout during fw download ");
				/* timed out */
				release_firmware(kim_gdata->fw_entry);
				return -ETIMEDOUT;
			}
			INIT_COMPLETION(kim_gdata->kim_rcvd);
			break;
		case ACTION_DELAY:	/* sleep */
			pr_info("sleep command in scr");
			action_ptr = &(((struct bts_action *)ptr)->data[0]);
			mdelay(((struct bts_action_delay *)action_ptr)->msec);
			break;
		}
		len =
		    len - (sizeof(struct bts_action) +
			   ((struct bts_action *)ptr)->size);
		ptr =
		    ptr + sizeof(struct bts_action) +
		    ((struct bts_action *)ptr)->size;
	}
	/* fw download complete */
	release_firmware(kim_gdata->fw_entry);
	return 0;
}

/**********************************************************************/
/* functions called from ST core */
/* called from ST Core, when REG_IN_PROGRESS (registration in progress)
 * can be because of
 * 1. response to read local version
 * 2. during send/recv's of firmware download
 */
void st_kim_recv(void *disc_data, const unsigned char *data, long count)
{
	struct st_data_s	*st_gdata = (struct st_data_s *)disc_data;
	struct kim_data_s	*kim_gdata = st_gdata->kim_data;

	/* proceed to gather all data and distinguish read fw version response
	 * from other fw responses when data gathering is complete
	 */
	kim_int_recv(kim_gdata, data, count);
	return;
}

/* to signal completion of line discipline installation
 * called from ST Core, upon tty_open
 */
void st_kim_complete(void *kim_data)
{
	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
	complete(&kim_gdata->ldisc_installed);
}

/**
 * st_kim_start - called from ST Core upon 1st registration
 *	This involves toggling the chip enable gpio, reading
 *	the firmware version from chip, forming the fw file name
 *	based on the chip version, requesting the fw, parsing it
 *	and perform download(send/recv).
 */
long st_kim_start(void *kim_data)
{
	long err = 0;
	long retry = POR_RETRY_COUNT;
	struct ti_st_plat_data	*pdata;
	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;

	pr_info(" %s", __func__);
	pdata = kim_gdata->kim_pdev->dev.platform_data;

	do {
		/* platform specific enabling code here */
		if (pdata->chip_enable)
			pdata->chip_enable(kim_gdata);

		/* re-initialize the completion */
		INIT_COMPLETION(kim_gdata->ldisc_installed);
		/* send notification to UIM */
		kim_gdata->ldisc_install = 1;
		pr_info("ldisc_install = 1");
		sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
				NULL, "install");
		/* wait for ldisc to be installed */
		err = wait_for_completion_interruptible_timeout(
			&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
		if (!err) {
			/* ldisc installation timeout,
			 * flush uart, power cycle BT_EN */
			pr_err("ldisc installation timeout");
			err = st_kim_stop(kim_gdata);
			continue;
		} else {
			/* ldisc installed now */
			pr_info("line discipline installed");
			err = download_firmware(kim_gdata);
			if (err != 0) {
				/* ldisc installed but fw download failed,
				 * flush uart & power cycle BT_EN */
				pr_err("download firmware failed");
				err = st_kim_stop(kim_gdata);
				continue;
			} else {	/* on success don't retry */
				break;
			}
		}
	} while (retry--);
	return err;
}

/**
 * st_kim_stop - stop communication with chip.
 *	This can be called from ST Core/KIM, on the-
 *	(a) last un-register when chip need not be powered there-after,
 *	(b) upon failure to either install ldisc or download firmware.
 *	The function is responsible to (a) notify UIM about un-installation,
 *	(b) flush UART if the ldisc was installed.
 *	(c) invoke platform's chip disabling routine.
 */
long st_kim_stop(void *kim_data)
{
	long err = 0;
	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
	struct ti_st_plat_data	*pdata =
		kim_gdata->kim_pdev->dev.platform_data;
	struct tty_struct	*tty = kim_gdata->core_data->tty;

	INIT_COMPLETION(kim_gdata->ldisc_installed);

	if (tty) {	/* can be called before ldisc is installed */
		/* Flush any pending characters in the driver and discipline. */
		tty_ldisc_flush(tty);
		tty_driver_flush_buffer(tty);
		tty->ops->flush_buffer(tty);
	}

	/* send uninstall notification to UIM */
	pr_info("ldisc_install = 0");
	kim_gdata->ldisc_install = 0;
	sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");

	/* wait for ldisc to be un-installed */
	err = wait_for_completion_interruptible_timeout(
		&kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
	if (!err) {		/* timeout */
		pr_err(" timed out waiting for ldisc to be un-installed");
		err = -ETIMEDOUT;
	}

	/* platform specific disable */
	if (pdata->chip_disable)
		pdata->chip_disable(kim_gdata);
	return err;
}

/**********************************************************************/
/* functions called from subsystems */
/* called when debugfs entry is read from */

static int show_version(struct seq_file *s, void *unused)
{
	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
	seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
			kim_gdata->version.chip, kim_gdata->version.maj_ver,
			kim_gdata->version.min_ver);
	return 0;
}

static int show_list(struct seq_file *s, void *unused)
{
	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
	kim_st_list_protocols(kim_gdata->core_data, s);
	return 0;
}

static ssize_t show_install(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	return sprintf(buf, "%d\n", kim_data->ldisc_install);
}

#ifdef DEBUG
static ssize_t store_dev_name(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t count)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	pr_debug("storing dev name >%s<", buf);
	strncpy(kim_data->dev_name, buf, count);
	pr_debug("stored dev name >%s<", kim_data->dev_name);
	return count;
}

static ssize_t store_baud_rate(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t count)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	pr_debug("storing baud rate >%s<", buf);
	sscanf(buf, "%ld", &kim_data->baud_rate);
	pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
	return count;
}
#endif	/* if DEBUG */

static ssize_t show_dev_name(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	return sprintf(buf, "%s\n", kim_data->dev_name);
}

static ssize_t show_baud_rate(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	return sprintf(buf, "%ld\n", kim_data->baud_rate);
}

static ssize_t show_flow_cntrl(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct kim_data_s *kim_data = dev_get_drvdata(dev);
	return sprintf(buf, "%d\n", kim_data->flow_cntrl);
}

/* structures specific for sysfs entries */
static struct kobj_attribute ldisc_install =
__ATTR(install, 0444, (void *)show_install, NULL);

static struct kobj_attribute uart_dev_name =
#ifdef DEBUG	/* TODO: move this to debug-fs if possible */
__ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
#else
__ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
#endif

static struct kobj_attribute uart_baud_rate =
#ifdef DEBUG	/* TODO: move to debugfs */
__ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
#else
__ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
#endif

static struct kobj_attribute uart_flow_cntrl =
__ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);

static struct attribute *uim_attrs[] = {
	&ldisc_install.attr,
	&uart_dev_name.attr,
	&uart_baud_rate.attr,
	&uart_flow_cntrl.attr,
	NULL,
};

static struct attribute_group uim_attr_grp = {
	.attrs = uim_attrs,
};

/**
 * st_kim_ref - reference the core's data
 *	This references the per-ST platform device in the arch/xx/
 *	board-xx.c file.
 *	This would enable multiple such platform devices to exist
 *	on a given platform
 */
void st_kim_ref(struct st_data_s **core_data, int id)
{
	struct platform_device	*pdev;
	struct kim_data_s	*kim_gdata;
	/* get kim_gdata reference from platform device */
	pdev = st_get_plat_device(id);
	if (!pdev) {
		*core_data = NULL;
		return;
	}
	kim_gdata = dev_get_drvdata(&pdev->dev);
	*core_data = kim_gdata->core_data;
}

static int kim_version_open(struct inode *i, struct file *f)
{
	return single_open(f, show_version, i->i_private);
}

static int kim_list_open(struct inode *i, struct file *f)
{
	return single_open(f, show_list, i->i_private);
}

static const struct file_operations version_debugfs_fops = {
	/* version info */
	.open = kim_version_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};
static const struct file_operations list_debugfs_fops = {
	/* protocols info */
	.open = kim_list_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

/**********************************************************************/
/* functions called from platform device driver subsystem
 * need to have a relevant platform device entry in the platform's
 * board-*.c file
 */

static struct dentry *kim_debugfs_dir;
static int kim_probe(struct platform_device *pdev)
{
	struct kim_data_s	*kim_gdata;
	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
	int err;

	if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
		/* multiple devices could exist */
		st_kim_devices[pdev->id] = pdev;
	} else {
		/* platform's sure about existence of 1 device */
		st_kim_devices[0] = pdev;
	}

	kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_ATOMIC);
	if (!kim_gdata) {
		pr_err("no mem to allocate");
		return -ENOMEM;
	}
	dev_set_drvdata(&pdev->dev, kim_gdata);

	err = st_core_init(&kim_gdata->core_data);
	if (err != 0) {
		pr_err(" ST core init failed");
		err = -EIO;
		goto err_core_init;
	}
	/* refer to itself */
	kim_gdata->core_data->kim_data = kim_gdata;

	/* get reference of pdev for request_firmware
	 */
	kim_gdata->kim_pdev = pdev;
	init_completion(&kim_gdata->kim_rcvd);
	init_completion(&kim_gdata->ldisc_installed);

	err = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
	if (err) {
		pr_err("failed to create sysfs entries");
		goto err_sysfs_group;
	}

	/* copying platform data */
	strncpy(kim_gdata->dev_name, pdata->dev_name, UART_DEV_NAME_LEN);
	kim_gdata->flow_cntrl = pdata->flow_cntrl;
	kim_gdata->baud_rate = pdata->baud_rate;
	pr_info("sysfs entries created\n");

	kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
	if (IS_ERR(kim_debugfs_dir)) {
		pr_err(" debugfs entries creation failed ");
		err = -EIO;
		goto err_debugfs_dir;
	}

	debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
				kim_gdata, &version_debugfs_fops);
	debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
				kim_gdata, &list_debugfs_fops);
	pr_info(" debugfs entries created ");
	return 0;

err_debugfs_dir:
	sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);

err_sysfs_group:
	st_core_exit(kim_gdata->core_data);

err_core_init:
	kfree(kim_gdata);

	return err;
}

static int kim_remove(struct platform_device *pdev)
{
	struct kim_data_s	*kim_gdata;

	kim_gdata = dev_get_drvdata(&pdev->dev);

	debugfs_remove_recursive(kim_debugfs_dir);
	sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
	pr_info("sysfs entries removed");

	kim_gdata->kim_pdev = NULL;
	st_core_exit(kim_gdata->core_data);

	kfree(kim_gdata);
	kim_gdata = NULL;
	return 0;
}

static int kim_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;

	if (pdata->suspend)
		return pdata->suspend(pdev, state);

	return -EOPNOTSUPP;
}

static int kim_resume(struct platform_device *pdev)
{
	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;

	if (pdata->resume)
		return pdata->resume(pdev);

	return -EOPNOTSUPP;
}

/**********************************************************************/
/* entry point for ST KIM module, called in from ST Core */
static struct platform_driver kim_platform_driver = {
	.probe = kim_probe,
	.remove = kim_remove,
	.suspend = kim_suspend,
	.resume = kim_resume,
	.driver = {
		.name = "kim",
		.owner = THIS_MODULE,
	},
};

module_platform_driver(kim_platform_driver);

MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud