1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Shared Transport Line discipline driver Core
4 * Init Manager module responsible for GPIO control
5 * and firmware download
6 * Copyright (C) 2009-2010 Texas Instruments
7 * Author: Pavan Savoy <pavan_savoy@ti.com>
8 */
9
10#define pr_fmt(fmt) "(stk) :" fmt
11#include <linux/platform_device.h>
12#include <linux/jiffies.h>
13#include <linux/firmware.h>
14#include <linux/delay.h>
15#include <linux/wait.h>
16#include <linux/gpio.h>
17#include <linux/debugfs.h>
18#include <linux/seq_file.h>
19#include <linux/sched.h>
20#include <linux/sysfs.h>
21#include <linux/tty.h>
22
23#include <linux/skbuff.h>
24#include <linux/ti_wilink_st.h>
25#include <linux/module.h>
26
27#define MAX_ST_DEVICES 3 /* Imagine 1 on each UART for now */
28static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
29
30/**********************************************************************/
31/* internal functions */
32
33/*
34 * st_get_plat_device -
35 * function which returns the reference to the platform device
36 * requested by id. As of now only 1 such device exists (id=0)
37 * the context requesting for reference can get the id to be
38 * requested by a. The protocol driver which is registering or
39 * b. the tty device which is opened.
40 */
41static struct platform_device *st_get_plat_device(int id)
42{
43 return st_kim_devices[id];
44}
45
46/*
47 * validate_firmware_response -
48 * function to return whether the firmware response was proper
49 * in case of error don't complete so that waiting for proper
50 * response times out
51 */
52static void validate_firmware_response(struct kim_data_s *kim_gdata)
53{
54 struct sk_buff *skb = kim_gdata->rx_skb;
55 if (!skb)
56 return;
57
58 /*
59 * these magic numbers are the position in the response buffer which
60 * allows us to distinguish whether the response is for the read
61 * version info. command
62 */
63 if (skb->data[2] == 0x01 && skb->data[3] == 0x01 &&
64 skb->data[4] == 0x10 && skb->data[5] == 0x00) {
65 /* fw version response */
66 memcpy(kim_gdata->resp_buffer,
67 kim_gdata->rx_skb->data,
68 kim_gdata->rx_skb->len);
69 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
70 kim_gdata->rx_skb = NULL;
71 kim_gdata->rx_count = 0;
72 } else if (unlikely(skb->data[5] != 0)) {
73 pr_err("no proper response during fw download");
74 pr_err("data6 %x", skb->data[5]);
75 kfree_skb(skb);
76 return; /* keep waiting for the proper response */
77 }
78 /* becos of all the script being downloaded */
79 complete_all(&kim_gdata->kim_rcvd);
80 kfree_skb(skb);
81}
82
83/*
84 * check for data len received inside kim_int_recv
85 * most often hit the last case to update state to waiting for data
86 */
87static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
88{
89 register int room = skb_tailroom(skb: kim_gdata->rx_skb);
90
91 pr_debug("len %d room %d", len, room);
92
93 if (!len) {
94 validate_firmware_response(kim_gdata);
95 } else if (len > room) {
96 /*
97 * Received packet's payload length is larger.
98 * We can't accommodate it in created skb.
99 */
100 pr_err("Data length is too large len %d room %d", len,
101 room);
102 kfree_skb(skb: kim_gdata->rx_skb);
103 } else {
104 /*
105 * Packet header has non-zero payload length and
106 * we have enough space in created skb. Lets read
107 * payload data */
108 kim_gdata->rx_state = ST_W4_DATA;
109 kim_gdata->rx_count = len;
110 return len;
111 }
112
113 /*
114 * Change ST LL state to continue to process next
115 * packet
116 */
117 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
118 kim_gdata->rx_skb = NULL;
119 kim_gdata->rx_count = 0;
120
121 return 0;
122}
123
124/*
125 * kim_int_recv - receive function called during firmware download
126 * firmware download responses on different UART drivers
127 * have been observed to come in bursts of different
128 * tty_receive and hence the logic
129 */
130static void kim_int_recv(struct kim_data_s *kim_gdata, const u8 *ptr,
131 size_t count)
132{
133 int len = 0;
134 unsigned char *plen;
135
136 pr_debug("%s", __func__);
137 /* Decode received bytes here */
138 while (count) {
139 if (kim_gdata->rx_count) {
140 len = min_t(unsigned int, kim_gdata->rx_count, count);
141 skb_put_data(skb: kim_gdata->rx_skb, data: ptr, len);
142 kim_gdata->rx_count -= len;
143 count -= len;
144 ptr += len;
145
146 if (kim_gdata->rx_count)
147 continue;
148
149 /* Check ST RX state machine , where are we? */
150 switch (kim_gdata->rx_state) {
151 /* Waiting for complete packet ? */
152 case ST_W4_DATA:
153 pr_debug("Complete pkt received");
154 validate_firmware_response(kim_gdata);
155 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
156 kim_gdata->rx_skb = NULL;
157 continue;
158 /* Waiting for Bluetooth event header ? */
159 case ST_W4_HEADER:
160 plen =
161 (unsigned char *)&kim_gdata->rx_skb->data[1];
162 pr_debug("event hdr: plen 0x%02x\n", *plen);
163 kim_check_data_len(kim_gdata, len: *plen);
164 continue;
165 } /* end of switch */
166 } /* end of if rx_state */
167 switch (*ptr) {
168 /* Bluetooth event packet? */
169 case 0x04:
170 kim_gdata->rx_state = ST_W4_HEADER;
171 kim_gdata->rx_count = 2;
172 break;
173 default:
174 pr_info("unknown packet");
175 ptr++;
176 count--;
177 continue;
178 }
179 ptr++;
180 count--;
181 kim_gdata->rx_skb =
182 alloc_skb(size: 1024+8, GFP_ATOMIC);
183 if (!kim_gdata->rx_skb) {
184 pr_err("can't allocate mem for new packet");
185 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
186 kim_gdata->rx_count = 0;
187 return;
188 }
189 skb_reserve(skb: kim_gdata->rx_skb, len: 8);
190 kim_gdata->rx_skb->cb[0] = 4;
191 kim_gdata->rx_skb->cb[1] = 0;
192
193 }
194 return;
195}
196
197static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
198{
199 unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
200 static const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
201 long timeout;
202
203 pr_debug("%s", __func__);
204
205 reinit_completion(x: &kim_gdata->kim_rcvd);
206 if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
207 pr_err("kim: couldn't write 4 bytes");
208 return -EIO;
209 }
210
211 timeout = wait_for_completion_interruptible_timeout(
212 x: &kim_gdata->kim_rcvd, timeout: msecs_to_jiffies(CMD_RESP_TIME));
213 if (timeout <= 0) {
214 pr_err(" waiting for ver info- timed out or received signal");
215 return timeout ? -ERESTARTSYS : -ETIMEDOUT;
216 }
217 reinit_completion(x: &kim_gdata->kim_rcvd);
218 /*
219 * the positions 12 & 13 in the response buffer provide with the
220 * chip, major & minor numbers
221 */
222
223 version =
224 MAKEWORD(kim_gdata->resp_buffer[12],
225 kim_gdata->resp_buffer[13]);
226 chip = (version & 0x7C00) >> 10;
227 min_ver = (version & 0x007F);
228 maj_ver = (version & 0x0380) >> 7;
229
230 if (version & 0x8000)
231 maj_ver |= 0x0008;
232
233 sprintf(buf: bts_scr_name, fmt: "ti-connectivity/TIInit_%d.%d.%d.bts",
234 chip, maj_ver, min_ver);
235
236 /* to be accessed later via sysfs entry */
237 kim_gdata->version.full = version;
238 kim_gdata->version.chip = chip;
239 kim_gdata->version.maj_ver = maj_ver;
240 kim_gdata->version.min_ver = min_ver;
241
242 pr_info("%s", bts_scr_name);
243 return 0;
244}
245
246static void skip_change_remote_baud(unsigned char **ptr, long *len)
247{
248 unsigned char *nxt_action, *cur_action;
249 cur_action = *ptr;
250
251 nxt_action = cur_action + sizeof(struct bts_action) +
252 ((struct bts_action *) cur_action)->size;
253
254 if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
255 pr_err("invalid action after change remote baud command");
256 } else {
257 *ptr = *ptr + sizeof(struct bts_action) +
258 ((struct bts_action *)cur_action)->size;
259 *len = *len - (sizeof(struct bts_action) +
260 ((struct bts_action *)cur_action)->size);
261 /* warn user on not commenting these in firmware */
262 pr_warn("skipping the wait event of change remote baud");
263 }
264}
265
266/*
267 * download_firmware -
268 * internal function which parses through the .bts firmware
269 * script file intreprets SEND, DELAY actions only as of now
270 */
271static long download_firmware(struct kim_data_s *kim_gdata)
272{
273 long err = 0;
274 long len = 0;
275 unsigned char *ptr = NULL;
276 unsigned char *action_ptr = NULL;
277 unsigned char bts_scr_name[40] = { 0 }; /* 40 char long bts scr name? */
278 int wr_room_space;
279 int cmd_size;
280 unsigned long timeout;
281
282 err = read_local_version(kim_gdata, bts_scr_name);
283 if (err != 0) {
284 pr_err("kim: failed to read local ver");
285 return err;
286 }
287 err =
288 request_firmware(fw: &kim_gdata->fw_entry, name: bts_scr_name,
289 device: &kim_gdata->kim_pdev->dev);
290 if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
291 (kim_gdata->fw_entry->size == 0))) {
292 pr_err(" request_firmware failed(errno %ld) for %s", err,
293 bts_scr_name);
294 return -EINVAL;
295 }
296 ptr = (void *)kim_gdata->fw_entry->data;
297 len = kim_gdata->fw_entry->size;
298 /*
299 * bts_header to remove out magic number and
300 * version
301 */
302 ptr += sizeof(struct bts_header);
303 len -= sizeof(struct bts_header);
304
305 while (len > 0 && ptr) {
306 pr_debug(" action size %d, type %d ",
307 ((struct bts_action *)ptr)->size,
308 ((struct bts_action *)ptr)->type);
309
310 switch (((struct bts_action *)ptr)->type) {
311 case ACTION_SEND_COMMAND: /* action send */
312 pr_debug("S");
313 action_ptr = &(((struct bts_action *)ptr)->data[0]);
314 if (unlikely
315 (((struct hci_command *)action_ptr)->opcode ==
316 0xFF36)) {
317 /*
318 * ignore remote change
319 * baud rate HCI VS command
320 */
321 pr_warn("change remote baud"
322 " rate command in firmware");
323 skip_change_remote_baud(ptr: &ptr, len: &len);
324 break;
325 }
326 /*
327 * Make sure we have enough free space in uart
328 * tx buffer to write current firmware command
329 */
330 cmd_size = ((struct bts_action *)ptr)->size;
331 timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
332 do {
333 wr_room_space =
334 st_get_uart_wr_room(st_gdata: kim_gdata->core_data);
335 if (wr_room_space < 0) {
336 pr_err("Unable to get free "
337 "space info from uart tx buffer");
338 release_firmware(fw: kim_gdata->fw_entry);
339 return wr_room_space;
340 }
341 mdelay(1); /* wait 1ms before checking room */
342 } while ((wr_room_space < cmd_size) &&
343 time_before(jiffies, timeout));
344
345 /* Timeout happened ? */
346 if (time_after_eq(jiffies, timeout)) {
347 pr_err("Timeout while waiting for free "
348 "free space in uart tx buffer");
349 release_firmware(fw: kim_gdata->fw_entry);
350 return -ETIMEDOUT;
351 }
352 /*
353 * reinit completion before sending for the
354 * relevant wait
355 */
356 reinit_completion(x: &kim_gdata->kim_rcvd);
357
358 /*
359 * Free space found in uart buffer, call st_int_write
360 * to send current firmware command to the uart tx
361 * buffer.
362 */
363 err = st_int_write(kim_gdata->core_data,
364 ((struct bts_action_send *)action_ptr)->data,
365 ((struct bts_action *)ptr)->size);
366 if (unlikely(err < 0)) {
367 release_firmware(fw: kim_gdata->fw_entry);
368 return err;
369 }
370 /*
371 * Check number of bytes written to the uart tx buffer
372 * and requested command write size
373 */
374 if (err != cmd_size) {
375 pr_err("Number of bytes written to uart "
376 "tx buffer are not matching with "
377 "requested cmd write size");
378 release_firmware(fw: kim_gdata->fw_entry);
379 return -EIO;
380 }
381 break;
382 case ACTION_WAIT_EVENT: /* wait */
383 pr_debug("W");
384 err = wait_for_completion_interruptible_timeout(
385 x: &kim_gdata->kim_rcvd,
386 timeout: msecs_to_jiffies(CMD_RESP_TIME));
387 if (err <= 0) {
388 pr_err("response timeout/signaled during fw download ");
389 /* timed out */
390 release_firmware(fw: kim_gdata->fw_entry);
391 return err ? -ERESTARTSYS : -ETIMEDOUT;
392 }
393 reinit_completion(x: &kim_gdata->kim_rcvd);
394 break;
395 case ACTION_DELAY: /* sleep */
396 pr_info("sleep command in scr");
397 action_ptr = &(((struct bts_action *)ptr)->data[0]);
398 mdelay(((struct bts_action_delay *)action_ptr)->msec);
399 break;
400 }
401 len =
402 len - (sizeof(struct bts_action) +
403 ((struct bts_action *)ptr)->size);
404 ptr =
405 ptr + sizeof(struct bts_action) +
406 ((struct bts_action *)ptr)->size;
407 }
408 /* fw download complete */
409 release_firmware(fw: kim_gdata->fw_entry);
410 return 0;
411}
412
413/**********************************************************************/
414/* functions called from ST core */
415/* called from ST Core, when REG_IN_PROGRESS (registration in progress)
416 * can be because of
417 * 1. response to read local version
418 * 2. during send/recv's of firmware download
419 */
420void st_kim_recv(void *disc_data, const u8 *data, size_t count)
421{
422 struct st_data_s *st_gdata = (struct st_data_s *)disc_data;
423 struct kim_data_s *kim_gdata = st_gdata->kim_data;
424
425 /*
426 * proceed to gather all data and distinguish read fw version response
427 * from other fw responses when data gathering is complete
428 */
429 kim_int_recv(kim_gdata, ptr: data, count);
430 return;
431}
432
433/*
434 * to signal completion of line discipline installation
435 * called from ST Core, upon tty_open
436 */
437void st_kim_complete(void *kim_data)
438{
439 struct kim_data_s *kim_gdata = (struct kim_data_s *)kim_data;
440 complete(&kim_gdata->ldisc_installed);
441}
442
443/*
444 * st_kim_start - called from ST Core upon 1st registration
445 * This involves toggling the chip enable gpio, reading
446 * the firmware version from chip, forming the fw file name
447 * based on the chip version, requesting the fw, parsing it
448 * and perform download(send/recv).
449 */
450long st_kim_start(void *kim_data)
451{
452 long err = 0;
453 long retry = POR_RETRY_COUNT;
454 struct ti_st_plat_data *pdata;
455 struct kim_data_s *kim_gdata = (struct kim_data_s *)kim_data;
456
457 pr_info(" %s", __func__);
458 pdata = kim_gdata->kim_pdev->dev.platform_data;
459
460 do {
461 /* platform specific enabling code here */
462 if (pdata->chip_enable)
463 pdata->chip_enable(kim_gdata);
464
465 /* Configure BT nShutdown to HIGH state */
466 gpio_set_value_cansleep(gpio: kim_gdata->nshutdown, GPIO_LOW);
467 mdelay(5); /* FIXME: a proper toggle */
468 gpio_set_value_cansleep(gpio: kim_gdata->nshutdown, GPIO_HIGH);
469 mdelay(100);
470 /* re-initialize the completion */
471 reinit_completion(x: &kim_gdata->ldisc_installed);
472 /* send notification to UIM */
473 kim_gdata->ldisc_install = 1;
474 pr_info("ldisc_install = 1");
475 sysfs_notify(kobj: &kim_gdata->kim_pdev->dev.kobj,
476 NULL, attr: "install");
477 /* wait for ldisc to be installed */
478 err = wait_for_completion_interruptible_timeout(
479 x: &kim_gdata->ldisc_installed, timeout: msecs_to_jiffies(LDISC_TIME));
480 if (!err) {
481 /*
482 * ldisc installation timeout,
483 * flush uart, power cycle BT_EN
484 */
485 pr_err("ldisc installation timeout");
486 err = st_kim_stop(kim_gdata);
487 continue;
488 } else {
489 /* ldisc installed now */
490 pr_info("line discipline installed");
491 err = download_firmware(kim_gdata);
492 if (err != 0) {
493 /*
494 * ldisc installed but fw download failed,
495 * flush uart & power cycle BT_EN
496 */
497 pr_err("download firmware failed");
498 err = st_kim_stop(kim_gdata);
499 continue;
500 } else { /* on success don't retry */
501 break;
502 }
503 }
504 } while (retry--);
505 return err;
506}
507
508/*
509 * st_kim_stop - stop communication with chip.
510 * This can be called from ST Core/KIM, on the-
511 * (a) last un-register when chip need not be powered there-after,
512 * (b) upon failure to either install ldisc or download firmware.
513 * The function is responsible to (a) notify UIM about un-installation,
514 * (b) flush UART if the ldisc was installed.
515 * (c) reset BT_EN - pull down nshutdown at the end.
516 * (d) invoke platform's chip disabling routine.
517 */
518long st_kim_stop(void *kim_data)
519{
520 long err = 0;
521 struct kim_data_s *kim_gdata = (struct kim_data_s *)kim_data;
522 struct ti_st_plat_data *pdata =
523 kim_gdata->kim_pdev->dev.platform_data;
524 struct tty_struct *tty = kim_gdata->core_data->tty;
525
526 reinit_completion(x: &kim_gdata->ldisc_installed);
527
528 if (tty) { /* can be called before ldisc is installed */
529 /* Flush any pending characters in the driver and discipline. */
530 tty_ldisc_flush(tty);
531 tty_driver_flush_buffer(tty);
532 }
533
534 /* send uninstall notification to UIM */
535 pr_info("ldisc_install = 0");
536 kim_gdata->ldisc_install = 0;
537 sysfs_notify(kobj: &kim_gdata->kim_pdev->dev.kobj, NULL, attr: "install");
538
539 /* wait for ldisc to be un-installed */
540 err = wait_for_completion_interruptible_timeout(
541 x: &kim_gdata->ldisc_installed, timeout: msecs_to_jiffies(LDISC_TIME));
542 if (!err) { /* timeout */
543 pr_err(" timed out waiting for ldisc to be un-installed");
544 err = -ETIMEDOUT;
545 }
546
547 /* By default configure BT nShutdown to LOW state */
548 gpio_set_value_cansleep(gpio: kim_gdata->nshutdown, GPIO_LOW);
549 mdelay(1);
550 gpio_set_value_cansleep(gpio: kim_gdata->nshutdown, GPIO_HIGH);
551 mdelay(1);
552 gpio_set_value_cansleep(gpio: kim_gdata->nshutdown, GPIO_LOW);
553
554 /* platform specific disable */
555 if (pdata->chip_disable)
556 pdata->chip_disable(kim_gdata);
557 return err;
558}
559
560/**********************************************************************/
561/* functions called from subsystems */
562/* called when debugfs entry is read from */
563
564static int version_show(struct seq_file *s, void *unused)
565{
566 struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
567 seq_printf(m: s, fmt: "%04X %d.%d.%d\n", kim_gdata->version.full,
568 kim_gdata->version.chip, kim_gdata->version.maj_ver,
569 kim_gdata->version.min_ver);
570 return 0;
571}
572
573static int list_show(struct seq_file *s, void *unused)
574{
575 struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
576 kim_st_list_protocols(kim_gdata->core_data, s);
577 return 0;
578}
579
580static ssize_t show_install(struct device *dev,
581 struct device_attribute *attr, char *buf)
582{
583 struct kim_data_s *kim_data = dev_get_drvdata(dev);
584 return sprintf(buf, fmt: "%d\n", kim_data->ldisc_install);
585}
586
587#ifdef DEBUG
588static ssize_t store_dev_name(struct device *dev,
589 struct device_attribute *attr, const char *buf, size_t count)
590{
591 struct kim_data_s *kim_data = dev_get_drvdata(dev);
592 pr_debug("storing dev name >%s<", buf);
593 strscpy(kim_data->dev_name, buf, sizeof(kim_data->dev_name));
594 pr_debug("stored dev name >%s<", kim_data->dev_name);
595 return count;
596}
597
598static ssize_t store_baud_rate(struct device *dev,
599 struct device_attribute *attr, const char *buf, size_t count)
600{
601 struct kim_data_s *kim_data = dev_get_drvdata(dev);
602 pr_debug("storing baud rate >%s<", buf);
603 sscanf(buf, "%ld", &kim_data->baud_rate);
604 pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
605 return count;
606}
607#endif /* if DEBUG */
608
609static ssize_t show_dev_name(struct device *dev,
610 struct device_attribute *attr, char *buf)
611{
612 struct kim_data_s *kim_data = dev_get_drvdata(dev);
613 return sprintf(buf, fmt: "%s\n", kim_data->dev_name);
614}
615
616static ssize_t show_baud_rate(struct device *dev,
617 struct device_attribute *attr, char *buf)
618{
619 struct kim_data_s *kim_data = dev_get_drvdata(dev);
620 return sprintf(buf, fmt: "%d\n", kim_data->baud_rate);
621}
622
623static ssize_t show_flow_cntrl(struct device *dev,
624 struct device_attribute *attr, char *buf)
625{
626 struct kim_data_s *kim_data = dev_get_drvdata(dev);
627 return sprintf(buf, fmt: "%d\n", kim_data->flow_cntrl);
628}
629
630/* structures specific for sysfs entries */
631static struct kobj_attribute ldisc_install =
632__ATTR(install, 0444, (void *)show_install, NULL);
633
634static struct kobj_attribute uart_dev_name =
635#ifdef DEBUG /* TODO: move this to debug-fs if possible */
636__ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
637#else
638__ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
639#endif
640
641static struct kobj_attribute uart_baud_rate =
642#ifdef DEBUG /* TODO: move to debugfs */
643__ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
644#else
645__ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
646#endif
647
648static struct kobj_attribute uart_flow_cntrl =
649__ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
650
651static struct attribute *uim_attrs[] = {
652 &ldisc_install.attr,
653 &uart_dev_name.attr,
654 &uart_baud_rate.attr,
655 &uart_flow_cntrl.attr,
656 NULL,
657};
658
659static const struct attribute_group uim_attr_grp = {
660 .attrs = uim_attrs,
661};
662
663/*
664 * st_kim_ref - reference the core's data
665 * This references the per-ST platform device in the arch/xx/
666 * board-xx.c file.
667 * This would enable multiple such platform devices to exist
668 * on a given platform
669 */
670void st_kim_ref(struct st_data_s **core_data, int id)
671{
672 struct platform_device *pdev;
673 struct kim_data_s *kim_gdata;
674 /* get kim_gdata reference from platform device */
675 pdev = st_get_plat_device(id);
676 if (!pdev)
677 goto err;
678 kim_gdata = platform_get_drvdata(pdev);
679 if (!kim_gdata)
680 goto err;
681
682 *core_data = kim_gdata->core_data;
683 return;
684err:
685 *core_data = NULL;
686}
687
688DEFINE_SHOW_ATTRIBUTE(version);
689DEFINE_SHOW_ATTRIBUTE(list);
690
691/**********************************************************************/
692/* functions called from platform device driver subsystem
693 * need to have a relevant platform device entry in the platform's
694 * board-*.c file
695 */
696
697static struct dentry *kim_debugfs_dir;
698static int kim_probe(struct platform_device *pdev)
699{
700 struct kim_data_s *kim_gdata;
701 struct ti_st_plat_data *pdata = pdev->dev.platform_data;
702 int err;
703
704 if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
705 /* multiple devices could exist */
706 st_kim_devices[pdev->id] = pdev;
707 } else {
708 /* platform's sure about existence of 1 device */
709 st_kim_devices[0] = pdev;
710 }
711
712 kim_gdata = kzalloc(size: sizeof(struct kim_data_s), GFP_KERNEL);
713 if (!kim_gdata) {
714 pr_err("no mem to allocate");
715 return -ENOMEM;
716 }
717 platform_set_drvdata(pdev, data: kim_gdata);
718
719 err = st_core_init(&kim_gdata->core_data);
720 if (err != 0) {
721 pr_err(" ST core init failed");
722 err = -EIO;
723 goto err_core_init;
724 }
725 /* refer to itself */
726 kim_gdata->core_data->kim_data = kim_gdata;
727
728 /* Claim the chip enable nShutdown gpio from the system */
729 kim_gdata->nshutdown = pdata->nshutdown_gpio;
730 err = gpio_request(gpio: kim_gdata->nshutdown, label: "kim");
731 if (unlikely(err)) {
732 pr_err(" gpio %d request failed ", kim_gdata->nshutdown);
733 goto err_sysfs_group;
734 }
735
736 /* Configure nShutdown GPIO as output=0 */
737 err = gpio_direction_output(gpio: kim_gdata->nshutdown, value: 0);
738 if (unlikely(err)) {
739 pr_err(" unable to configure gpio %d", kim_gdata->nshutdown);
740 goto err_sysfs_group;
741 }
742 /* get reference of pdev for request_firmware */
743 kim_gdata->kim_pdev = pdev;
744 init_completion(x: &kim_gdata->kim_rcvd);
745 init_completion(x: &kim_gdata->ldisc_installed);
746
747 err = sysfs_create_group(kobj: &pdev->dev.kobj, grp: &uim_attr_grp);
748 if (err) {
749 pr_err("failed to create sysfs entries");
750 goto err_sysfs_group;
751 }
752
753 /* copying platform data */
754 strscpy(kim_gdata->dev_name, pdata->dev_name,
755 sizeof(kim_gdata->dev_name));
756 kim_gdata->flow_cntrl = pdata->flow_cntrl;
757 kim_gdata->baud_rate = pdata->baud_rate;
758 pr_info("sysfs entries created\n");
759
760 kim_debugfs_dir = debugfs_create_dir(name: "ti-st", NULL);
761
762 debugfs_create_file(name: "version", S_IRUGO, parent: kim_debugfs_dir,
763 data: kim_gdata, fops: &version_fops);
764 debugfs_create_file(name: "protocols", S_IRUGO, parent: kim_debugfs_dir,
765 data: kim_gdata, fops: &list_fops);
766 return 0;
767
768err_sysfs_group:
769 st_core_exit(kim_gdata->core_data);
770
771err_core_init:
772 kfree(objp: kim_gdata);
773
774 return err;
775}
776
777static void kim_remove(struct platform_device *pdev)
778{
779 /* free the GPIOs requested */
780 struct ti_st_plat_data *pdata = pdev->dev.platform_data;
781 struct kim_data_s *kim_gdata;
782
783 kim_gdata = platform_get_drvdata(pdev);
784
785 /*
786 * Free the Bluetooth/FM/GPIO
787 * nShutdown gpio from the system
788 */
789 gpio_free(gpio: pdata->nshutdown_gpio);
790 pr_info("nshutdown GPIO Freed");
791
792 debugfs_remove_recursive(dentry: kim_debugfs_dir);
793 sysfs_remove_group(kobj: &pdev->dev.kobj, grp: &uim_attr_grp);
794 pr_info("sysfs entries removed");
795
796 kim_gdata->kim_pdev = NULL;
797 st_core_exit(kim_gdata->core_data);
798
799 kfree(objp: kim_gdata);
800 kim_gdata = NULL;
801}
802
803static int kim_suspend(struct platform_device *pdev, pm_message_t state)
804{
805 struct ti_st_plat_data *pdata = pdev->dev.platform_data;
806
807 if (pdata->suspend)
808 return pdata->suspend(pdev, state);
809
810 return 0;
811}
812
813static int kim_resume(struct platform_device *pdev)
814{
815 struct ti_st_plat_data *pdata = pdev->dev.platform_data;
816
817 if (pdata->resume)
818 return pdata->resume(pdev);
819
820 return 0;
821}
822
823/**********************************************************************/
824/* entry point for ST KIM module, called in from ST Core */
825static struct platform_driver kim_platform_driver = {
826 .probe = kim_probe,
827 .remove_new = kim_remove,
828 .suspend = kim_suspend,
829 .resume = kim_resume,
830 .driver = {
831 .name = "kim",
832 },
833};
834
835module_platform_driver(kim_platform_driver);
836
837MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
838MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
839MODULE_LICENSE("GPL");
840

source code of linux/drivers/misc/ti-st/st_kim.c