1 // SPDX-License-Identifier: GPL-2.0+
2
3 /*
4 * Multifunction core driver for Zodiac Inflight Innovations RAVE
5 * Supervisory Processor(SP) MCU that is connected via dedicated UART
6 * port
7 *
8 * Copyright (C) 2017 Zodiac Inflight Innovations
9 */
10
11 #include <linux/atomic.h>
12 #include <linux/crc-ccitt.h>
13 #include <linux/delay.h>
14 #include <linux/export.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/kernel.h>
18 #include <linux/mfd/rave-sp.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/of_device.h>
22 #include <linux/sched.h>
23 #include <linux/serdev.h>
24 #include <asm/unaligned.h>
25
26 /*
27 * UART protocol using following entities:
28 * - message to MCU => ACK response
29 * - event from MCU => event ACK
30 *
31 * Frame structure:
32 * <STX> <DATA> <CHECKSUM> <ETX>
33 * Where:
34 * - STX - is start of transmission character
35 * - ETX - end of transmission
36 * - DATA - payload
37 * - CHECKSUM - checksum calculated on <DATA>
38 *
39 * If <DATA> or <CHECKSUM> contain one of control characters, then it is
40 * escaped using <DLE> control code. Added <DLE> does not participate in
41 * checksum calculation.
42 */
43 #define RAVE_SP_STX 0x02
44 #define RAVE_SP_ETX 0x03
45 #define RAVE_SP_DLE 0x10
46
47 #define RAVE_SP_MAX_DATA_SIZE 64
48 #define RAVE_SP_CHECKSUM_8B2C 1
49 #define RAVE_SP_CHECKSUM_CCITT 2
50 #define RAVE_SP_CHECKSUM_SIZE RAVE_SP_CHECKSUM_CCITT
51 /*
52 * We don't store STX, ETX and unescaped bytes, so Rx is only
53 * DATA + CSUM
54 */
55 #define RAVE_SP_RX_BUFFER_SIZE \
56 (RAVE_SP_MAX_DATA_SIZE + RAVE_SP_CHECKSUM_SIZE)
57
58 #define RAVE_SP_STX_ETX_SIZE 2
59 /*
60 * For Tx we have to have space for everything, STX, EXT and
61 * potentially stuffed DATA + CSUM data + csum
62 */
63 #define RAVE_SP_TX_BUFFER_SIZE \
64 (RAVE_SP_STX_ETX_SIZE + 2 * RAVE_SP_RX_BUFFER_SIZE)
65
66 /**
67 * enum rave_sp_deframer_state - Possible state for de-framer
68 *
69 * @RAVE_SP_EXPECT_SOF: Scanning input for start-of-frame marker
70 * @RAVE_SP_EXPECT_DATA: Got start of frame marker, collecting frame
71 * @RAVE_SP_EXPECT_ESCAPED_DATA: Got escape character, collecting escaped byte
72 */
73 enum rave_sp_deframer_state {
74 RAVE_SP_EXPECT_SOF,
75 RAVE_SP_EXPECT_DATA,
76 RAVE_SP_EXPECT_ESCAPED_DATA,
77 };
78
79 /**
80 * struct rave_sp_deframer - Device protocol deframer
81 *
82 * @state: Current state of the deframer
83 * @data: Buffer used to collect deframed data
84 * @length: Number of bytes de-framed so far
85 */
86 struct rave_sp_deframer {
87 enum rave_sp_deframer_state state;
88 unsigned char data[RAVE_SP_RX_BUFFER_SIZE];
89 size_t length;
90 };
91
92 /**
93 * struct rave_sp_reply - Reply as per RAVE device protocol
94 *
95 * @length: Expected reply length
96 * @data: Buffer to store reply payload in
97 * @code: Expected reply code
98 * @ackid: Expected reply ACK ID
99 * @completion: Successful reply reception completion
100 */
101 struct rave_sp_reply {
102 size_t length;
103 void *data;
104 u8 code;
105 u8 ackid;
106 struct completion received;
107 };
108
109 /**
110 * struct rave_sp_checksum - Variant specific checksum implementation details
111 *
112 * @length: Calculated checksum length
113 * @subroutine: Utilized checksum algorithm implementation
114 */
115 struct rave_sp_checksum {
116 size_t length;
117 void (*subroutine)(const u8 *, size_t, u8 *);
118 };
119
120 struct rave_sp_version {
121 u8 hardware;
122 __le16 major;
123 u8 minor;
124 u8 letter[2];
125 } __packed;
126
127 struct rave_sp_status {
128 struct rave_sp_version bootloader_version;
129 struct rave_sp_version firmware_version;
130 u16 rdu_eeprom_flag;
131 u16 dds_eeprom_flag;
132 u8 pic_flag;
133 u8 orientation;
134 u32 etc;
135 s16 temp[2];
136 u8 backlight_current[3];
137 u8 dip_switch;
138 u8 host_interrupt;
139 u16 voltage_28;
140 u8 i2c_device_status;
141 u8 power_status;
142 u8 general_status;
143 u8 deprecated1;
144 u8 power_led_status;
145 u8 deprecated2;
146 u8 periph_power_shutoff;
147 } __packed;
148
149 /**
150 * struct rave_sp_variant_cmds - Variant specific command routines
151 *
152 * @translate: Generic to variant specific command mapping routine
153 * @get_status: Variant specific implementation of CMD_GET_STATUS
154 */
155 struct rave_sp_variant_cmds {
156 int (*translate)(enum rave_sp_command);
157 int (*get_status)(struct rave_sp *sp, struct rave_sp_status *);
158 };
159
160 /**
161 * struct rave_sp_variant - RAVE supervisory processor core variant
162 *
163 * @checksum: Variant specific checksum implementation
164 * @cmd: Variant specific command pointer table
165 *
166 */
167 struct rave_sp_variant {
168 const struct rave_sp_checksum *checksum;
169 struct rave_sp_variant_cmds cmd;
170 };
171
172 /**
173 * struct rave_sp - RAVE supervisory processor core
174 *
175 * @serdev: Pointer to underlying serdev
176 * @deframer: Stored state of the protocol deframer
177 * @ackid: ACK ID used in last reply sent to the device
178 * @bus_lock: Lock to serialize access to the device
179 * @reply_lock: Lock protecting @reply
180 * @reply: Pointer to memory to store reply payload
181 *
182 * @variant: Device variant specific information
183 * @event_notifier_list: Input event notification chain
184 *
185 * @part_number_firmware: Firmware version
186 * @part_number_bootloader: Bootloader version
187 */
188 struct rave_sp {
189 struct serdev_device *serdev;
190 struct rave_sp_deframer deframer;
191 atomic_t ackid;
192 struct mutex bus_lock;
193 struct mutex reply_lock;
194 struct rave_sp_reply *reply;
195
196 const struct rave_sp_variant *variant;
197 struct blocking_notifier_head event_notifier_list;
198
199 const char *part_number_firmware;
200 const char *part_number_bootloader;
201 };
202
rave_sp_id_is_event(u8 code)203 static bool rave_sp_id_is_event(u8 code)
204 {
205 return (code & 0xF0) == RAVE_SP_EVNT_BASE;
206 }
207
rave_sp_unregister_event_notifier(struct device * dev,void * res)208 static void rave_sp_unregister_event_notifier(struct device *dev, void *res)
209 {
210 struct rave_sp *sp = dev_get_drvdata(dev->parent);
211 struct notifier_block *nb = *(struct notifier_block **)res;
212 struct blocking_notifier_head *bnh = &sp->event_notifier_list;
213
214 WARN_ON(blocking_notifier_chain_unregister(bnh, nb));
215 }
216
devm_rave_sp_register_event_notifier(struct device * dev,struct notifier_block * nb)217 int devm_rave_sp_register_event_notifier(struct device *dev,
218 struct notifier_block *nb)
219 {
220 struct rave_sp *sp = dev_get_drvdata(dev->parent);
221 struct notifier_block **rcnb;
222 int ret;
223
224 rcnb = devres_alloc(rave_sp_unregister_event_notifier,
225 sizeof(*rcnb), GFP_KERNEL);
226 if (!rcnb)
227 return -ENOMEM;
228
229 ret = blocking_notifier_chain_register(&sp->event_notifier_list, nb);
230 if (!ret) {
231 *rcnb = nb;
232 devres_add(dev, rcnb);
233 } else {
234 devres_free(rcnb);
235 }
236
237 return ret;
238 }
239 EXPORT_SYMBOL_GPL(devm_rave_sp_register_event_notifier);
240
csum_8b2c(const u8 * buf,size_t size,u8 * crc)241 static void csum_8b2c(const u8 *buf, size_t size, u8 *crc)
242 {
243 *crc = *buf++;
244 size--;
245
246 while (size--)
247 *crc += *buf++;
248
249 *crc = 1 + ~(*crc);
250 }
251
csum_ccitt(const u8 * buf,size_t size,u8 * crc)252 static void csum_ccitt(const u8 *buf, size_t size, u8 *crc)
253 {
254 const u16 calculated = crc_ccitt_false(0xffff, buf, size);
255
256 /*
257 * While the rest of the wire protocol is little-endian,
258 * CCITT-16 CRC in RDU2 device is sent out in big-endian order.
259 */
260 put_unaligned_be16(calculated, crc);
261 }
262
stuff(unsigned char * dest,const unsigned char * src,size_t n)263 static void *stuff(unsigned char *dest, const unsigned char *src, size_t n)
264 {
265 while (n--) {
266 const unsigned char byte = *src++;
267
268 switch (byte) {
269 case RAVE_SP_STX:
270 case RAVE_SP_ETX:
271 case RAVE_SP_DLE:
272 *dest++ = RAVE_SP_DLE;
273 /* FALLTHROUGH */
274 default:
275 *dest++ = byte;
276 }
277 }
278
279 return dest;
280 }
281
rave_sp_write(struct rave_sp * sp,const u8 * data,u8 data_size)282 static int rave_sp_write(struct rave_sp *sp, const u8 *data, u8 data_size)
283 {
284 const size_t checksum_length = sp->variant->checksum->length;
285 unsigned char frame[RAVE_SP_TX_BUFFER_SIZE];
286 unsigned char crc[RAVE_SP_CHECKSUM_SIZE];
287 unsigned char *dest = frame;
288 size_t length;
289
290 if (WARN_ON(checksum_length > sizeof(crc)))
291 return -ENOMEM;
292
293 if (WARN_ON(data_size > sizeof(frame)))
294 return -ENOMEM;
295
296 sp->variant->checksum->subroutine(data, data_size, crc);
297
298 *dest++ = RAVE_SP_STX;
299 dest = stuff(dest, data, data_size);
300 dest = stuff(dest, crc, checksum_length);
301 *dest++ = RAVE_SP_ETX;
302
303 length = dest - frame;
304
305 print_hex_dump_debug("rave-sp tx: ", DUMP_PREFIX_NONE,
306 16, 1, frame, length, false);
307
308 return serdev_device_write(sp->serdev, frame, length, HZ);
309 }
310
rave_sp_reply_code(u8 command)311 static u8 rave_sp_reply_code(u8 command)
312 {
313 /*
314 * There isn't a single rule that describes command code ->
315 * ACK code transformation, but, going through various
316 * versions of ICDs, there appear to be three distinct groups
317 * that can be described by simple transformation.
318 */
319 switch (command) {
320 case 0xA0 ... 0xBE:
321 /*
322 * Commands implemented by firmware found in RDU1 and
323 * older devices all seem to obey the following rule
324 */
325 return command + 0x20;
326 case 0xE0 ... 0xEF:
327 /*
328 * Events emitted by all versions of the firmare use
329 * least significant bit to get an ACK code
330 */
331 return command | 0x01;
332 default:
333 /*
334 * Commands implemented by firmware found in RDU2 are
335 * similar to "old" commands, but they use slightly
336 * different offset
337 */
338 return command + 0x40;
339 }
340 }
341
rave_sp_exec(struct rave_sp * sp,void * __data,size_t data_size,void * reply_data,size_t reply_data_size)342 int rave_sp_exec(struct rave_sp *sp,
343 void *__data, size_t data_size,
344 void *reply_data, size_t reply_data_size)
345 {
346 struct rave_sp_reply reply = {
347 .data = reply_data,
348 .length = reply_data_size,
349 .received = COMPLETION_INITIALIZER_ONSTACK(reply.received),
350 };
351 unsigned char *data = __data;
352 int command, ret = 0;
353 u8 ackid;
354
355 command = sp->variant->cmd.translate(data[0]);
356 if (command < 0)
357 return command;
358
359 ackid = atomic_inc_return(&sp->ackid);
360 reply.ackid = ackid;
361 reply.code = rave_sp_reply_code((u8)command),
362
363 mutex_lock(&sp->bus_lock);
364
365 mutex_lock(&sp->reply_lock);
366 sp->reply = &reply;
367 mutex_unlock(&sp->reply_lock);
368
369 data[0] = command;
370 data[1] = ackid;
371
372 rave_sp_write(sp, data, data_size);
373
374 if (!wait_for_completion_timeout(&reply.received, HZ)) {
375 dev_err(&sp->serdev->dev, "Command timeout\n");
376 ret = -ETIMEDOUT;
377
378 mutex_lock(&sp->reply_lock);
379 sp->reply = NULL;
380 mutex_unlock(&sp->reply_lock);
381 }
382
383 mutex_unlock(&sp->bus_lock);
384 return ret;
385 }
386 EXPORT_SYMBOL_GPL(rave_sp_exec);
387
rave_sp_receive_event(struct rave_sp * sp,const unsigned char * data,size_t length)388 static void rave_sp_receive_event(struct rave_sp *sp,
389 const unsigned char *data, size_t length)
390 {
391 u8 cmd[] = {
392 [0] = rave_sp_reply_code(data[0]),
393 [1] = data[1],
394 };
395
396 rave_sp_write(sp, cmd, sizeof(cmd));
397
398 blocking_notifier_call_chain(&sp->event_notifier_list,
399 rave_sp_action_pack(data[0], data[2]),
400 NULL);
401 }
402
rave_sp_receive_reply(struct rave_sp * sp,const unsigned char * data,size_t length)403 static void rave_sp_receive_reply(struct rave_sp *sp,
404 const unsigned char *data, size_t length)
405 {
406 struct device *dev = &sp->serdev->dev;
407 struct rave_sp_reply *reply;
408 const size_t payload_length = length - 2;
409
410 mutex_lock(&sp->reply_lock);
411 reply = sp->reply;
412
413 if (reply) {
414 if (reply->code == data[0] && reply->ackid == data[1] &&
415 payload_length >= reply->length) {
416 /*
417 * We are relying on memcpy(dst, src, 0) to be a no-op
418 * when handling commands that have a no-payload reply
419 */
420 memcpy(reply->data, &data[2], reply->length);
421 complete(&reply->received);
422 sp->reply = NULL;
423 } else {
424 dev_err(dev, "Ignoring incorrect reply\n");
425 dev_dbg(dev, "Code: expected = 0x%08x received = 0x%08x\n",
426 reply->code, data[0]);
427 dev_dbg(dev, "ACK ID: expected = 0x%08x received = 0x%08x\n",
428 reply->ackid, data[1]);
429 dev_dbg(dev, "Length: expected = %zu received = %zu\n",
430 reply->length, payload_length);
431 }
432 }
433
434 mutex_unlock(&sp->reply_lock);
435 }
436
rave_sp_receive_frame(struct rave_sp * sp,const unsigned char * data,size_t length)437 static void rave_sp_receive_frame(struct rave_sp *sp,
438 const unsigned char *data,
439 size_t length)
440 {
441 const size_t checksum_length = sp->variant->checksum->length;
442 const size_t payload_length = length - checksum_length;
443 const u8 *crc_reported = &data[payload_length];
444 struct device *dev = &sp->serdev->dev;
445 u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
446
447 if (unlikely(checksum_length > sizeof(crc_calculated))) {
448 dev_warn(dev, "Checksum too long, dropping\n");
449 return;
450 }
451
452 print_hex_dump_debug("rave-sp rx: ", DUMP_PREFIX_NONE,
453 16, 1, data, length, false);
454
455 if (unlikely(length <= checksum_length)) {
456 dev_warn(dev, "Dropping short frame\n");
457 return;
458 }
459
460 sp->variant->checksum->subroutine(data, payload_length,
461 crc_calculated);
462
463 if (memcmp(crc_calculated, crc_reported, checksum_length)) {
464 dev_warn(dev, "Dropping bad frame\n");
465 return;
466 }
467
468 if (rave_sp_id_is_event(data[0]))
469 rave_sp_receive_event(sp, data, length);
470 else
471 rave_sp_receive_reply(sp, data, length);
472 }
473
rave_sp_receive_buf(struct serdev_device * serdev,const unsigned char * buf,size_t size)474 static int rave_sp_receive_buf(struct serdev_device *serdev,
475 const unsigned char *buf, size_t size)
476 {
477 struct device *dev = &serdev->dev;
478 struct rave_sp *sp = dev_get_drvdata(dev);
479 struct rave_sp_deframer *deframer = &sp->deframer;
480 const unsigned char *src = buf;
481 const unsigned char *end = buf + size;
482
483 while (src < end) {
484 const unsigned char byte = *src++;
485
486 switch (deframer->state) {
487 case RAVE_SP_EXPECT_SOF:
488 if (byte == RAVE_SP_STX)
489 deframer->state = RAVE_SP_EXPECT_DATA;
490 break;
491
492 case RAVE_SP_EXPECT_DATA:
493 /*
494 * Treat special byte values first
495 */
496 switch (byte) {
497 case RAVE_SP_ETX:
498 rave_sp_receive_frame(sp,
499 deframer->data,
500 deframer->length);
501 /*
502 * Once we extracted a complete frame
503 * out of a stream, we call it done
504 * and proceed to bailing out while
505 * resetting the framer to initial
506 * state, regardless if we've consumed
507 * all of the stream or not.
508 */
509 goto reset_framer;
510 case RAVE_SP_STX:
511 dev_warn(dev, "Bad frame: STX before ETX\n");
512 /*
513 * If we encounter second "start of
514 * the frame" marker before seeing
515 * corresponding "end of frame", we
516 * reset the framer and ignore both:
517 * frame started by first SOF and
518 * frame started by current SOF.
519 *
520 * NOTE: The above means that only the
521 * frame started by third SOF, sent
522 * after this one will have a chance
523 * to get throught.
524 */
525 goto reset_framer;
526 case RAVE_SP_DLE:
527 deframer->state = RAVE_SP_EXPECT_ESCAPED_DATA;
528 /*
529 * If we encounter escape sequence we
530 * need to skip it and collect the
531 * byte that follows. We do it by
532 * forcing the next iteration of the
533 * encompassing while loop.
534 */
535 continue;
536 }
537 /*
538 * For the rest of the bytes, that are not
539 * speical snoflakes, we do the same thing
540 * that we do to escaped data - collect it in
541 * deframer buffer
542 */
543
544 /* FALLTHROUGH */
545
546 case RAVE_SP_EXPECT_ESCAPED_DATA:
547 if (deframer->length == sizeof(deframer->data)) {
548 dev_warn(dev, "Bad frame: Too long\n");
549 /*
550 * If the amount of data we've
551 * accumulated for current frame so
552 * far starts to exceed the capacity
553 * of deframer's buffer, there's
554 * nothing else we can do but to
555 * discard that data and start
556 * assemblying a new frame again
557 */
558 goto reset_framer;
559 }
560
561 deframer->data[deframer->length++] = byte;
562
563 /*
564 * We've extracted out special byte, now we
565 * can go back to regular data collecting
566 */
567 deframer->state = RAVE_SP_EXPECT_DATA;
568 break;
569 }
570 }
571
572 /*
573 * The only way to get out of the above loop and end up here
574 * is throught consuming all of the supplied data, so here we
575 * report that we processed it all.
576 */
577 return size;
578
579 reset_framer:
580 /*
581 * NOTE: A number of codepaths that will drop us here will do
582 * so before consuming all 'size' bytes of the data passed by
583 * serdev layer. We rely on the fact that serdev layer will
584 * re-execute this handler with the remainder of the Rx bytes
585 * once we report actual number of bytes that we processed.
586 */
587 deframer->state = RAVE_SP_EXPECT_SOF;
588 deframer->length = 0;
589
590 return src - buf;
591 }
592
rave_sp_rdu1_cmd_translate(enum rave_sp_command command)593 static int rave_sp_rdu1_cmd_translate(enum rave_sp_command command)
594 {
595 if (command >= RAVE_SP_CMD_STATUS &&
596 command <= RAVE_SP_CMD_CONTROL_EVENTS)
597 return command;
598
599 return -EINVAL;
600 }
601
rave_sp_rdu2_cmd_translate(enum rave_sp_command command)602 static int rave_sp_rdu2_cmd_translate(enum rave_sp_command command)
603 {
604 if (command >= RAVE_SP_CMD_GET_FIRMWARE_VERSION &&
605 command <= RAVE_SP_CMD_GET_GPIO_STATE)
606 return command;
607
608 if (command == RAVE_SP_CMD_REQ_COPPER_REV) {
609 /*
610 * As per RDU2 ICD 3.4.47 CMD_GET_COPPER_REV code is
611 * different from that for RDU1 and it is set to 0x28.
612 */
613 return 0x28;
614 }
615
616 return rave_sp_rdu1_cmd_translate(command);
617 }
618
rave_sp_default_cmd_translate(enum rave_sp_command command)619 static int rave_sp_default_cmd_translate(enum rave_sp_command command)
620 {
621 /*
622 * All of the following command codes were taken from "Table :
623 * Communications Protocol Message Types" in section 3.3
624 * "MESSAGE TYPES" of Rave PIC24 ICD.
625 */
626 switch (command) {
627 case RAVE_SP_CMD_GET_FIRMWARE_VERSION:
628 return 0x11;
629 case RAVE_SP_CMD_GET_BOOTLOADER_VERSION:
630 return 0x12;
631 case RAVE_SP_CMD_BOOT_SOURCE:
632 return 0x14;
633 case RAVE_SP_CMD_SW_WDT:
634 return 0x1C;
635 case RAVE_SP_CMD_PET_WDT:
636 return 0x1D;
637 case RAVE_SP_CMD_RESET:
638 return 0x1E;
639 case RAVE_SP_CMD_RESET_REASON:
640 return 0x1F;
641 case RAVE_SP_CMD_RMB_EEPROM:
642 return 0x20;
643 default:
644 return -EINVAL;
645 }
646 }
647
devm_rave_sp_version(struct device * dev,struct rave_sp_version * version)648 static const char *devm_rave_sp_version(struct device *dev,
649 struct rave_sp_version *version)
650 {
651 /*
652 * NOTE: The format string below uses %02d to display u16
653 * intentionally for the sake of backwards compatibility with
654 * legacy software.
655 */
656 return devm_kasprintf(dev, GFP_KERNEL, "%02d%02d%02d.%c%c\n",
657 version->hardware,
658 le16_to_cpu(version->major),
659 version->minor,
660 version->letter[0],
661 version->letter[1]);
662 }
663
rave_sp_rdu1_get_status(struct rave_sp * sp,struct rave_sp_status * status)664 static int rave_sp_rdu1_get_status(struct rave_sp *sp,
665 struct rave_sp_status *status)
666 {
667 u8 cmd[] = {
668 [0] = RAVE_SP_CMD_STATUS,
669 [1] = 0
670 };
671
672 return rave_sp_exec(sp, cmd, sizeof(cmd), status, sizeof(*status));
673 }
674
rave_sp_emulated_get_status(struct rave_sp * sp,struct rave_sp_status * status)675 static int rave_sp_emulated_get_status(struct rave_sp *sp,
676 struct rave_sp_status *status)
677 {
678 u8 cmd[] = {
679 [0] = RAVE_SP_CMD_GET_FIRMWARE_VERSION,
680 [1] = 0,
681 };
682 int ret;
683
684 ret = rave_sp_exec(sp, cmd, sizeof(cmd), &status->firmware_version,
685 sizeof(status->firmware_version));
686 if (ret)
687 return ret;
688
689 cmd[0] = RAVE_SP_CMD_GET_BOOTLOADER_VERSION;
690 return rave_sp_exec(sp, cmd, sizeof(cmd), &status->bootloader_version,
691 sizeof(status->bootloader_version));
692 }
693
rave_sp_get_status(struct rave_sp * sp)694 static int rave_sp_get_status(struct rave_sp *sp)
695 {
696 struct device *dev = &sp->serdev->dev;
697 struct rave_sp_status status;
698 const char *version;
699 int ret;
700
701 ret = sp->variant->cmd.get_status(sp, &status);
702 if (ret)
703 return ret;
704
705 version = devm_rave_sp_version(dev, &status.firmware_version);
706 if (!version)
707 return -ENOMEM;
708
709 sp->part_number_firmware = version;
710
711 version = devm_rave_sp_version(dev, &status.bootloader_version);
712 if (!version)
713 return -ENOMEM;
714
715 sp->part_number_bootloader = version;
716
717 return 0;
718 }
719
720 static const struct rave_sp_checksum rave_sp_checksum_8b2c = {
721 .length = 1,
722 .subroutine = csum_8b2c,
723 };
724
725 static const struct rave_sp_checksum rave_sp_checksum_ccitt = {
726 .length = 2,
727 .subroutine = csum_ccitt,
728 };
729
730 static const struct rave_sp_variant rave_sp_legacy = {
731 .checksum = &rave_sp_checksum_ccitt,
732 .cmd = {
733 .translate = rave_sp_default_cmd_translate,
734 .get_status = rave_sp_emulated_get_status,
735 },
736 };
737
738 static const struct rave_sp_variant rave_sp_rdu1 = {
739 .checksum = &rave_sp_checksum_8b2c,
740 .cmd = {
741 .translate = rave_sp_rdu1_cmd_translate,
742 .get_status = rave_sp_rdu1_get_status,
743 },
744 };
745
746 static const struct rave_sp_variant rave_sp_rdu2 = {
747 .checksum = &rave_sp_checksum_ccitt,
748 .cmd = {
749 .translate = rave_sp_rdu2_cmd_translate,
750 .get_status = rave_sp_emulated_get_status,
751 },
752 };
753
754 static const struct of_device_id rave_sp_dt_ids[] = {
755 { .compatible = "zii,rave-sp-niu", .data = &rave_sp_legacy },
756 { .compatible = "zii,rave-sp-mezz", .data = &rave_sp_legacy },
757 { .compatible = "zii,rave-sp-esb", .data = &rave_sp_legacy },
758 { .compatible = "zii,rave-sp-rdu1", .data = &rave_sp_rdu1 },
759 { .compatible = "zii,rave-sp-rdu2", .data = &rave_sp_rdu2 },
760 { /* sentinel */ }
761 };
762
763 static const struct serdev_device_ops rave_sp_serdev_device_ops = {
764 .receive_buf = rave_sp_receive_buf,
765 .write_wakeup = serdev_device_write_wakeup,
766 };
767
rave_sp_probe(struct serdev_device * serdev)768 static int rave_sp_probe(struct serdev_device *serdev)
769 {
770 struct device *dev = &serdev->dev;
771 const char *unknown = "unknown\n";
772 struct rave_sp *sp;
773 u32 baud;
774 int ret;
775
776 if (of_property_read_u32(dev->of_node, "current-speed", &baud)) {
777 dev_err(dev,
778 "'current-speed' is not specified in device node\n");
779 return -EINVAL;
780 }
781
782 sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL);
783 if (!sp)
784 return -ENOMEM;
785
786 sp->serdev = serdev;
787 dev_set_drvdata(dev, sp);
788
789 sp->variant = of_device_get_match_data(dev);
790 if (!sp->variant)
791 return -ENODEV;
792
793 mutex_init(&sp->bus_lock);
794 mutex_init(&sp->reply_lock);
795 BLOCKING_INIT_NOTIFIER_HEAD(&sp->event_notifier_list);
796
797 serdev_device_set_client_ops(serdev, &rave_sp_serdev_device_ops);
798 ret = devm_serdev_device_open(dev, serdev);
799 if (ret)
800 return ret;
801
802 serdev_device_set_baudrate(serdev, baud);
803 serdev_device_set_flow_control(serdev, false);
804
805 ret = serdev_device_set_parity(serdev, SERDEV_PARITY_NONE);
806 if (ret) {
807 dev_err(dev, "Failed to set parity\n");
808 return ret;
809 }
810
811 ret = rave_sp_get_status(sp);
812 if (ret) {
813 dev_warn(dev, "Failed to get firmware status: %d\n", ret);
814 sp->part_number_firmware = unknown;
815 sp->part_number_bootloader = unknown;
816 }
817
818 /*
819 * Those strings already have a \n embedded, so there's no
820 * need to have one in format string.
821 */
822 dev_info(dev, "Firmware version: %s", sp->part_number_firmware);
823 dev_info(dev, "Bootloader version: %s", sp->part_number_bootloader);
824
825 return devm_of_platform_populate(dev);
826 }
827
828 MODULE_DEVICE_TABLE(of, rave_sp_dt_ids);
829
830 static struct serdev_device_driver rave_sp_drv = {
831 .probe = rave_sp_probe,
832 .driver = {
833 .name = "rave-sp",
834 .of_match_table = rave_sp_dt_ids,
835 },
836 };
837 module_serdev_device_driver(rave_sp_drv);
838
839 MODULE_LICENSE("GPL");
840 MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");
841 MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");
842 MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
843 MODULE_DESCRIPTION("RAVE SP core driver");
844
