xref: /openbmc/linux/drivers/misc/ti-st/st_kim.c (revision 81d67439)
1 /*
2  *  Shared Transport Line discipline driver Core
3  *	Init Manager module responsible for GPIO control
4  *	and firmware download
5  *  Copyright (C) 2009-2010 Texas Instruments
6  *  Author: Pavan Savoy <pavan_savoy@ti.com>
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License version 2 as
10  *  published by the Free Software Foundation.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  *
21  */
22 
23 #define pr_fmt(fmt) "(stk) :" fmt
24 #include <linux/platform_device.h>
25 #include <linux/jiffies.h>
26 #include <linux/firmware.h>
27 #include <linux/delay.h>
28 #include <linux/wait.h>
29 #include <linux/gpio.h>
30 #include <linux/debugfs.h>
31 #include <linux/seq_file.h>
32 #include <linux/sched.h>
33 #include <linux/sysfs.h>
34 #include <linux/tty.h>
35 
36 #include <linux/skbuff.h>
37 #include <linux/ti_wilink_st.h>
38 
39 
40 #define MAX_ST_DEVICES	3	/* Imagine 1 on each UART for now */
41 static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
42 
43 /**********************************************************************/
44 /* internal functions */
45 
46 /**
47  * st_get_plat_device -
48  *	function which returns the reference to the platform device
49  *	requested by id. As of now only 1 such device exists (id=0)
50  *	the context requesting for reference can get the id to be
51  *	requested by a. The protocol driver which is registering or
52  *	b. the tty device which is opened.
53  */
54 static struct platform_device *st_get_plat_device(int id)
55 {
56 	return st_kim_devices[id];
57 }
58 
59 /**
60  * validate_firmware_response -
61  *	function to return whether the firmware response was proper
62  *	in case of error don't complete so that waiting for proper
63  *	response times out
64  */
65 void validate_firmware_response(struct kim_data_s *kim_gdata)
66 {
67 	struct sk_buff *skb = kim_gdata->rx_skb;
68 	if (unlikely(skb->data[5] != 0)) {
69 		pr_err("no proper response during fw download");
70 		pr_err("data6 %x", skb->data[5]);
71 		return;		/* keep waiting for the proper response */
72 	}
73 	/* becos of all the script being downloaded */
74 	complete_all(&kim_gdata->kim_rcvd);
75 	kfree_skb(skb);
76 }
77 
78 /* check for data len received inside kim_int_recv
79  * most often hit the last case to update state to waiting for data
80  */
81 static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
82 {
83 	register int room = skb_tailroom(kim_gdata->rx_skb);
84 
85 	pr_debug("len %d room %d", len, room);
86 
87 	if (!len) {
88 		validate_firmware_response(kim_gdata);
89 	} else if (len > room) {
90 		/* Received packet's payload length is larger.
91 		 * We can't accommodate it in created skb.
92 		 */
93 		pr_err("Data length is too large len %d room %d", len,
94 			   room);
95 		kfree_skb(kim_gdata->rx_skb);
96 	} else {
97 		/* Packet header has non-zero payload length and
98 		 * we have enough space in created skb. Lets read
99 		 * payload data */
100 		kim_gdata->rx_state = ST_W4_DATA;
101 		kim_gdata->rx_count = len;
102 		return len;
103 	}
104 
105 	/* Change ST LL state to continue to process next
106 	 * packet */
107 	kim_gdata->rx_state = ST_W4_PACKET_TYPE;
108 	kim_gdata->rx_skb = NULL;
109 	kim_gdata->rx_count = 0;
110 
111 	return 0;
112 }
113 
114 /**
115  * kim_int_recv - receive function called during firmware download
116  *	firmware download responses on different UART drivers
117  *	have been observed to come in bursts of different
118  *	tty_receive and hence the logic
119  */
120 void kim_int_recv(struct kim_data_s *kim_gdata,
121 	const unsigned char *data, long count)
122 {
123 	const unsigned char *ptr;
124 	int len = 0, type = 0;
125 	unsigned char *plen;
126 
127 	pr_debug("%s", __func__);
128 	/* Decode received bytes here */
129 	ptr = data;
130 	if (unlikely(ptr == NULL)) {
131 		pr_err(" received null from TTY ");
132 		return;
133 	}
134 
135 	while (count) {
136 		if (kim_gdata->rx_count) {
137 			len = min_t(unsigned int, kim_gdata->rx_count, count);
138 			memcpy(skb_put(kim_gdata->rx_skb, len), ptr, len);
139 			kim_gdata->rx_count -= len;
140 			count -= len;
141 			ptr += len;
142 
143 			if (kim_gdata->rx_count)
144 				continue;
145 
146 			/* Check ST RX state machine , where are we? */
147 			switch (kim_gdata->rx_state) {
148 				/* Waiting for complete packet ? */
149 			case ST_W4_DATA:
150 				pr_debug("Complete pkt received");
151 				validate_firmware_response(kim_gdata);
152 				kim_gdata->rx_state = ST_W4_PACKET_TYPE;
153 				kim_gdata->rx_skb = NULL;
154 				continue;
155 				/* Waiting for Bluetooth event header ? */
156 			case ST_W4_HEADER:
157 				plen =
158 				(unsigned char *)&kim_gdata->rx_skb->data[1];
159 				pr_debug("event hdr: plen 0x%02x\n", *plen);
160 				kim_check_data_len(kim_gdata, *plen);
161 				continue;
162 			}	/* end of switch */
163 		}		/* end of if rx_state */
164 		switch (*ptr) {
165 			/* Bluetooth event packet? */
166 		case 0x04:
167 			kim_gdata->rx_state = ST_W4_HEADER;
168 			kim_gdata->rx_count = 2;
169 			type = *ptr;
170 			break;
171 		default:
172 			pr_info("unknown packet");
173 			ptr++;
174 			count--;
175 			continue;
176 		}
177 		ptr++;
178 		count--;
179 		kim_gdata->rx_skb =
180 			alloc_skb(1024+8, GFP_ATOMIC);
181 		if (!kim_gdata->rx_skb) {
182 			pr_err("can't allocate mem for new packet");
183 			kim_gdata->rx_state = ST_W4_PACKET_TYPE;
184 			kim_gdata->rx_count = 0;
185 			return;
186 		}
187 		skb_reserve(kim_gdata->rx_skb, 8);
188 		kim_gdata->rx_skb->cb[0] = 4;
189 		kim_gdata->rx_skb->cb[1] = 0;
190 
191 	}
192 	return;
193 }
194 
195 static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
196 {
197 	unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
198 	const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
199 
200 	pr_debug("%s", __func__);
201 
202 	INIT_COMPLETION(kim_gdata->kim_rcvd);
203 	if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
204 		pr_err("kim: couldn't write 4 bytes");
205 		return -EIO;
206 	}
207 
208 	if (!wait_for_completion_timeout
209 	    (&kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME))) {
210 		pr_err(" waiting for ver info- timed out ");
211 		return -ETIMEDOUT;
212 	}
213 
214 	version =
215 		MAKEWORD(kim_gdata->resp_buffer[13],
216 				kim_gdata->resp_buffer[14]);
217 	chip = (version & 0x7C00) >> 10;
218 	min_ver = (version & 0x007F);
219 	maj_ver = (version & 0x0380) >> 7;
220 
221 	if (version & 0x8000)
222 		maj_ver |= 0x0008;
223 
224 	sprintf(bts_scr_name, "TIInit_%d.%d.%d.bts", chip, maj_ver, min_ver);
225 
226 	/* to be accessed later via sysfs entry */
227 	kim_gdata->version.full = version;
228 	kim_gdata->version.chip = chip;
229 	kim_gdata->version.maj_ver = maj_ver;
230 	kim_gdata->version.min_ver = min_ver;
231 
232 	pr_info("%s", bts_scr_name);
233 	return 0;
234 }
235 
236 void skip_change_remote_baud(unsigned char **ptr, long *len)
237 {
238 	unsigned char *nxt_action, *cur_action;
239 	cur_action = *ptr;
240 
241 	nxt_action = cur_action + sizeof(struct bts_action) +
242 		((struct bts_action *) cur_action)->size;
243 
244 	if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
245 		pr_err("invalid action after change remote baud command");
246 	} else {
247 		*ptr = *ptr + sizeof(struct bts_action) +
248 			((struct bts_action *)cur_action)->size;
249 		*len = *len - (sizeof(struct bts_action) +
250 				((struct bts_action *)cur_action)->size);
251 		/* warn user on not commenting these in firmware */
252 		pr_warn("skipping the wait event of change remote baud");
253 	}
254 }
255 
256 /**
257  * download_firmware -
258  *	internal function which parses through the .bts firmware
259  *	script file intreprets SEND, DELAY actions only as of now
260  */
261 static long download_firmware(struct kim_data_s *kim_gdata)
262 {
263 	long err = 0;
264 	long len = 0;
265 	unsigned char *ptr = NULL;
266 	unsigned char *action_ptr = NULL;
267 	unsigned char bts_scr_name[30] = { 0 };	/* 30 char long bts scr name? */
268 	int wr_room_space;
269 	int cmd_size;
270 	unsigned long timeout;
271 
272 	err = read_local_version(kim_gdata, bts_scr_name);
273 	if (err != 0) {
274 		pr_err("kim: failed to read local ver");
275 		return err;
276 	}
277 	err =
278 	    request_firmware(&kim_gdata->fw_entry, bts_scr_name,
279 			     &kim_gdata->kim_pdev->dev);
280 	if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
281 		     (kim_gdata->fw_entry->size == 0))) {
282 		pr_err(" request_firmware failed(errno %ld) for %s", err,
283 			   bts_scr_name);
284 		return -EINVAL;
285 	}
286 	ptr = (void *)kim_gdata->fw_entry->data;
287 	len = kim_gdata->fw_entry->size;
288 	/* bts_header to remove out magic number and
289 	 * version
290 	 */
291 	ptr += sizeof(struct bts_header);
292 	len -= sizeof(struct bts_header);
293 
294 	while (len > 0 && ptr) {
295 		pr_debug(" action size %d, type %d ",
296 			   ((struct bts_action *)ptr)->size,
297 			   ((struct bts_action *)ptr)->type);
298 
299 		switch (((struct bts_action *)ptr)->type) {
300 		case ACTION_SEND_COMMAND:	/* action send */
301 			action_ptr = &(((struct bts_action *)ptr)->data[0]);
302 			if (unlikely
303 			    (((struct hci_command *)action_ptr)->opcode ==
304 			     0xFF36)) {
305 				/* ignore remote change
306 				 * baud rate HCI VS command */
307 				pr_warn("change remote baud"
308 				    " rate command in firmware");
309 				skip_change_remote_baud(&ptr, &len);
310 				break;
311 			}
312 			/*
313 			 * Make sure we have enough free space in uart
314 			 * tx buffer to write current firmware command
315 			 */
316 			cmd_size = ((struct bts_action *)ptr)->size;
317 			timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
318 			do {
319 				wr_room_space =
320 					st_get_uart_wr_room(kim_gdata->core_data);
321 				if (wr_room_space < 0) {
322 					pr_err("Unable to get free "
323 							"space info from uart tx buffer");
324 					release_firmware(kim_gdata->fw_entry);
325 					return wr_room_space;
326 				}
327 				mdelay(1); /* wait 1ms before checking room */
328 			} while ((wr_room_space < cmd_size) &&
329 					time_before(jiffies, timeout));
330 
331 			/* Timeout happened ? */
332 			if (time_after_eq(jiffies, timeout)) {
333 				pr_err("Timeout while waiting for free "
334 						"free space in uart tx buffer");
335 				release_firmware(kim_gdata->fw_entry);
336 				return -ETIMEDOUT;
337 			}
338 
339 			/*
340 			 * Free space found in uart buffer, call st_int_write
341 			 * to send current firmware command to the uart tx
342 			 * buffer.
343 			 */
344 			err = st_int_write(kim_gdata->core_data,
345 			((struct bts_action_send *)action_ptr)->data,
346 					   ((struct bts_action *)ptr)->size);
347 			if (unlikely(err < 0)) {
348 				release_firmware(kim_gdata->fw_entry);
349 				return err;
350 			}
351 			/*
352 			 * Check number of bytes written to the uart tx buffer
353 			 * and requested command write size
354 			 */
355 			if (err != cmd_size) {
356 				pr_err("Number of bytes written to uart "
357 						"tx buffer are not matching with "
358 						"requested cmd write size");
359 				release_firmware(kim_gdata->fw_entry);
360 				return -EIO;
361 			}
362 			break;
363 		case ACTION_WAIT_EVENT:  /* wait */
364 			if (!wait_for_completion_timeout
365 					(&kim_gdata->kim_rcvd,
366 					 msecs_to_jiffies(CMD_RESP_TIME))) {
367 				pr_err("response timeout during fw download ");
368 				/* timed out */
369 				release_firmware(kim_gdata->fw_entry);
370 				return -ETIMEDOUT;
371 			}
372 			INIT_COMPLETION(kim_gdata->kim_rcvd);
373 			break;
374 		case ACTION_DELAY:	/* sleep */
375 			pr_info("sleep command in scr");
376 			action_ptr = &(((struct bts_action *)ptr)->data[0]);
377 			mdelay(((struct bts_action_delay *)action_ptr)->msec);
378 			break;
379 		}
380 		len =
381 		    len - (sizeof(struct bts_action) +
382 			   ((struct bts_action *)ptr)->size);
383 		ptr =
384 		    ptr + sizeof(struct bts_action) +
385 		    ((struct bts_action *)ptr)->size;
386 	}
387 	/* fw download complete */
388 	release_firmware(kim_gdata->fw_entry);
389 	return 0;
390 }
391 
392 /**********************************************************************/
393 /* functions called from ST core */
394 /* called from ST Core, when REG_IN_PROGRESS (registration in progress)
395  * can be because of
396  * 1. response to read local version
397  * 2. during send/recv's of firmware download
398  */
399 void st_kim_recv(void *disc_data, const unsigned char *data, long count)
400 {
401 	struct st_data_s	*st_gdata = (struct st_data_s *)disc_data;
402 	struct kim_data_s	*kim_gdata = st_gdata->kim_data;
403 
404 	/* copy to local buffer */
405 	if (unlikely(data[4] == 0x01 && data[5] == 0x10 && data[0] == 0x04)) {
406 		/* must be the read_ver_cmd */
407 		memcpy(kim_gdata->resp_buffer, data, count);
408 		complete_all(&kim_gdata->kim_rcvd);
409 		return;
410 	} else {
411 		kim_int_recv(kim_gdata, data, count);
412 		/* either completes or times out */
413 	}
414 	return;
415 }
416 
417 /* to signal completion of line discipline installation
418  * called from ST Core, upon tty_open
419  */
420 void st_kim_complete(void *kim_data)
421 {
422 	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
423 	complete(&kim_gdata->ldisc_installed);
424 }
425 
426 /**
427  * st_kim_start - called from ST Core upon 1st registration
428  *	This involves toggling the chip enable gpio, reading
429  *	the firmware version from chip, forming the fw file name
430  *	based on the chip version, requesting the fw, parsing it
431  *	and perform download(send/recv).
432  */
433 long st_kim_start(void *kim_data)
434 {
435 	long err = 0;
436 	long retry = POR_RETRY_COUNT;
437 	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
438 
439 	pr_info(" %s", __func__);
440 
441 	do {
442 		/* Configure BT nShutdown to HIGH state */
443 		gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
444 		mdelay(5);	/* FIXME: a proper toggle */
445 		gpio_set_value(kim_gdata->nshutdown, GPIO_HIGH);
446 		mdelay(100);
447 		/* re-initialize the completion */
448 		INIT_COMPLETION(kim_gdata->ldisc_installed);
449 		/* send notification to UIM */
450 		kim_gdata->ldisc_install = 1;
451 		pr_info("ldisc_install = 1");
452 		sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
453 				NULL, "install");
454 		/* wait for ldisc to be installed */
455 		err = wait_for_completion_timeout(&kim_gdata->ldisc_installed,
456 				msecs_to_jiffies(LDISC_TIME));
457 		if (!err) {	/* timeout */
458 			pr_err("line disc installation timed out ");
459 			kim_gdata->ldisc_install = 0;
460 			pr_info("ldisc_install = 0");
461 			sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
462 					NULL, "install");
463 			err = -ETIMEDOUT;
464 			continue;
465 		} else {
466 			/* ldisc installed now */
467 			pr_info(" line discipline installed ");
468 			err = download_firmware(kim_gdata);
469 			if (err != 0) {
470 				pr_err("download firmware failed");
471 				kim_gdata->ldisc_install = 0;
472 				pr_info("ldisc_install = 0");
473 				sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
474 						NULL, "install");
475 				continue;
476 			} else {	/* on success don't retry */
477 				break;
478 			}
479 		}
480 	} while (retry--);
481 	return err;
482 }
483 
484 /**
485  * st_kim_stop - called from ST Core, on the last un-registration
486  *	toggle low the chip enable gpio
487  */
488 long st_kim_stop(void *kim_data)
489 {
490 	long err = 0;
491 	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
492 
493 	INIT_COMPLETION(kim_gdata->ldisc_installed);
494 
495 	/* Flush any pending characters in the driver and discipline. */
496 	tty_ldisc_flush(kim_gdata->core_data->tty);
497 	tty_driver_flush_buffer(kim_gdata->core_data->tty);
498 
499 	/* send uninstall notification to UIM */
500 	pr_info("ldisc_install = 0");
501 	kim_gdata->ldisc_install = 0;
502 	sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");
503 
504 	/* wait for ldisc to be un-installed */
505 	err = wait_for_completion_timeout(&kim_gdata->ldisc_installed,
506 			msecs_to_jiffies(LDISC_TIME));
507 	if (!err) {		/* timeout */
508 		pr_err(" timed out waiting for ldisc to be un-installed");
509 		return -ETIMEDOUT;
510 	}
511 
512 	/* By default configure BT nShutdown to LOW state */
513 	gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
514 	mdelay(1);
515 	gpio_set_value(kim_gdata->nshutdown, GPIO_HIGH);
516 	mdelay(1);
517 	gpio_set_value(kim_gdata->nshutdown, GPIO_LOW);
518 	return err;
519 }
520 
521 /**********************************************************************/
522 /* functions called from subsystems */
523 /* called when debugfs entry is read from */
524 
525 static int show_version(struct seq_file *s, void *unused)
526 {
527 	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
528 	seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
529 			kim_gdata->version.chip, kim_gdata->version.maj_ver,
530 			kim_gdata->version.min_ver);
531 	return 0;
532 }
533 
534 static int show_list(struct seq_file *s, void *unused)
535 {
536 	struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
537 	kim_st_list_protocols(kim_gdata->core_data, s);
538 	return 0;
539 }
540 
541 static ssize_t show_install(struct device *dev,
542 		struct device_attribute *attr, char *buf)
543 {
544 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
545 	return sprintf(buf, "%d\n", kim_data->ldisc_install);
546 }
547 
548 static ssize_t show_dev_name(struct device *dev,
549 		struct device_attribute *attr, char *buf)
550 {
551 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
552 	return sprintf(buf, "%s\n", kim_data->dev_name);
553 }
554 
555 static ssize_t show_baud_rate(struct device *dev,
556 		struct device_attribute *attr, char *buf)
557 {
558 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
559 	return sprintf(buf, "%ld\n", kim_data->baud_rate);
560 }
561 
562 static ssize_t show_flow_cntrl(struct device *dev,
563 		struct device_attribute *attr, char *buf)
564 {
565 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
566 	return sprintf(buf, "%d\n", kim_data->flow_cntrl);
567 }
568 
569 /* structures specific for sysfs entries */
570 static struct kobj_attribute ldisc_install =
571 __ATTR(install, 0444, (void *)show_install, NULL);
572 
573 static struct kobj_attribute uart_dev_name =
574 __ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
575 
576 static struct kobj_attribute uart_baud_rate =
577 __ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
578 
579 static struct kobj_attribute uart_flow_cntrl =
580 __ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
581 
582 static struct attribute *uim_attrs[] = {
583 	&ldisc_install.attr,
584 	&uart_dev_name.attr,
585 	&uart_baud_rate.attr,
586 	&uart_flow_cntrl.attr,
587 	NULL,
588 };
589 
590 static struct attribute_group uim_attr_grp = {
591 	.attrs = uim_attrs,
592 };
593 
594 /**
595  * st_kim_ref - reference the core's data
596  *	This references the per-ST platform device in the arch/xx/
597  *	board-xx.c file.
598  *	This would enable multiple such platform devices to exist
599  *	on a given platform
600  */
601 void st_kim_ref(struct st_data_s **core_data, int id)
602 {
603 	struct platform_device	*pdev;
604 	struct kim_data_s	*kim_gdata;
605 	/* get kim_gdata reference from platform device */
606 	pdev = st_get_plat_device(id);
607 	if (!pdev) {
608 		*core_data = NULL;
609 		return;
610 	}
611 	kim_gdata = dev_get_drvdata(&pdev->dev);
612 	*core_data = kim_gdata->core_data;
613 }
614 
615 static int kim_version_open(struct inode *i, struct file *f)
616 {
617 	return single_open(f, show_version, i->i_private);
618 }
619 
620 static int kim_list_open(struct inode *i, struct file *f)
621 {
622 	return single_open(f, show_list, i->i_private);
623 }
624 
625 static const struct file_operations version_debugfs_fops = {
626 	/* version info */
627 	.open = kim_version_open,
628 	.read = seq_read,
629 	.llseek = seq_lseek,
630 	.release = single_release,
631 };
632 static const struct file_operations list_debugfs_fops = {
633 	/* protocols info */
634 	.open = kim_list_open,
635 	.read = seq_read,
636 	.llseek = seq_lseek,
637 	.release = single_release,
638 };
639 
640 /**********************************************************************/
641 /* functions called from platform device driver subsystem
642  * need to have a relevant platform device entry in the platform's
643  * board-*.c file
644  */
645 
646 struct dentry *kim_debugfs_dir;
647 static int kim_probe(struct platform_device *pdev)
648 {
649 	long status;
650 	struct kim_data_s	*kim_gdata;
651 	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
652 
653 	if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
654 		/* multiple devices could exist */
655 		st_kim_devices[pdev->id] = pdev;
656 	} else {
657 		/* platform's sure about existence of 1 device */
658 		st_kim_devices[0] = pdev;
659 	}
660 
661 	kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_ATOMIC);
662 	if (!kim_gdata) {
663 		pr_err("no mem to allocate");
664 		return -ENOMEM;
665 	}
666 	dev_set_drvdata(&pdev->dev, kim_gdata);
667 
668 	status = st_core_init(&kim_gdata->core_data);
669 	if (status != 0) {
670 		pr_err(" ST core init failed");
671 		return -EIO;
672 	}
673 	/* refer to itself */
674 	kim_gdata->core_data->kim_data = kim_gdata;
675 
676 	/* Claim the chip enable nShutdown gpio from the system */
677 	kim_gdata->nshutdown = pdata->nshutdown_gpio;
678 	status = gpio_request(kim_gdata->nshutdown, "kim");
679 	if (unlikely(status)) {
680 		pr_err(" gpio %ld request failed ", kim_gdata->nshutdown);
681 		return status;
682 	}
683 
684 	/* Configure nShutdown GPIO as output=0 */
685 	status = gpio_direction_output(kim_gdata->nshutdown, 0);
686 	if (unlikely(status)) {
687 		pr_err(" unable to configure gpio %ld", kim_gdata->nshutdown);
688 		return status;
689 	}
690 	/* get reference of pdev for request_firmware
691 	 */
692 	kim_gdata->kim_pdev = pdev;
693 	init_completion(&kim_gdata->kim_rcvd);
694 	init_completion(&kim_gdata->ldisc_installed);
695 
696 	status = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
697 	if (status) {
698 		pr_err("failed to create sysfs entries");
699 		return status;
700 	}
701 
702 	/* copying platform data */
703 	strncpy(kim_gdata->dev_name, pdata->dev_name, UART_DEV_NAME_LEN);
704 	kim_gdata->flow_cntrl = pdata->flow_cntrl;
705 	kim_gdata->baud_rate = pdata->baud_rate;
706 	pr_info("sysfs entries created\n");
707 
708 	kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
709 	if (IS_ERR(kim_debugfs_dir)) {
710 		pr_err(" debugfs entries creation failed ");
711 		kim_debugfs_dir = NULL;
712 		return -EIO;
713 	}
714 
715 	debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
716 				kim_gdata, &version_debugfs_fops);
717 	debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
718 				kim_gdata, &list_debugfs_fops);
719 	pr_info(" debugfs entries created ");
720 	return 0;
721 }
722 
723 static int kim_remove(struct platform_device *pdev)
724 {
725 	/* free the GPIOs requested */
726 	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
727 	struct kim_data_s	*kim_gdata;
728 
729 	kim_gdata = dev_get_drvdata(&pdev->dev);
730 
731 	/* Free the Bluetooth/FM/GPIO
732 	 * nShutdown gpio from the system
733 	 */
734 	gpio_free(pdata->nshutdown_gpio);
735 	pr_info("nshutdown GPIO Freed");
736 
737 	debugfs_remove_recursive(kim_debugfs_dir);
738 	sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
739 	pr_info("sysfs entries removed");
740 
741 	kim_gdata->kim_pdev = NULL;
742 	st_core_exit(kim_gdata->core_data);
743 
744 	kfree(kim_gdata);
745 	kim_gdata = NULL;
746 	return 0;
747 }
748 
749 int kim_suspend(struct platform_device *pdev, pm_message_t state)
750 {
751 	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
752 
753 	if (pdata->suspend)
754 		return pdata->suspend(pdev, state);
755 
756 	return -EOPNOTSUPP;
757 }
758 
759 int kim_resume(struct platform_device *pdev)
760 {
761 	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
762 
763 	if (pdata->resume)
764 		return pdata->resume(pdev);
765 
766 	return -EOPNOTSUPP;
767 }
768 
769 /**********************************************************************/
770 /* entry point for ST KIM module, called in from ST Core */
771 static struct platform_driver kim_platform_driver = {
772 	.probe = kim_probe,
773 	.remove = kim_remove,
774 	.suspend = kim_suspend,
775 	.resume = kim_resume,
776 	.driver = {
777 		.name = "kim",
778 		.owner = THIS_MODULE,
779 	},
780 };
781 
782 static int __init st_kim_init(void)
783 {
784 	return platform_driver_register(&kim_platform_driver);
785 }
786 
787 static void __exit st_kim_deinit(void)
788 {
789 	platform_driver_unregister(&kim_platform_driver);
790 }
791 
792 
793 module_init(st_kim_init);
794 module_exit(st_kim_deinit);
795 MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
796 MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
797 MODULE_LICENSE("GPL");
798