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Merge tag 'xfs-6.1-for-linus' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
[linux-block.git] / drivers / hid / hid-mcp2221.c
CommitLineData
67a95c21
RG		 1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * MCP2221A - Microchip USB to I2C Host Protocol Bridge
4 *
5 * Copyright (c) 2020, Rishi Gupta <gupt21@gmail.com>
6 *
b266eacf 7 * Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/20005565B.pdf
67a95c21
RG		 8 */
9
10#include <linux/module.h>
11#include <linux/err.h>
12#include <linux/mutex.h>
13#include <linux/completion.h>
14#include <linux/delay.h>
15#include <linux/hid.h>
16#include <linux/hidraw.h>
17#include <linux/i2c.h>
328de1c5 18#include <linux/gpio/driver.h>
67a95c21
RG		 19#include "hid-ids.h"
20
21/* Commands codes in a raw output report */
22enum {
23 MCP2221_I2C_WR_DATA = 0x90,
24 MCP2221_I2C_WR_NO_STOP = 0x94,
25 MCP2221_I2C_RD_DATA = 0x91,
26 MCP2221_I2C_RD_RPT_START = 0x93,
27 MCP2221_I2C_GET_DATA = 0x40,
28 MCP2221_I2C_PARAM_OR_STATUS = 0x10,
29 MCP2221_I2C_SET_SPEED = 0x20,
30 MCP2221_I2C_CANCEL = 0x10,
328de1c5
RG		 31 MCP2221_GPIO_SET = 0x50,
32 MCP2221_GPIO_GET = 0x51,
67a95c21
RG		 33};
34
35/* Response codes in a raw input report */
36enum {
37 MCP2221_SUCCESS = 0x00,
38 MCP2221_I2C_ENG_BUSY = 0x01,
39 MCP2221_I2C_START_TOUT = 0x12,
40 MCP2221_I2C_STOP_TOUT = 0x62,
41 MCP2221_I2C_WRADDRL_TOUT = 0x23,
42 MCP2221_I2C_WRDATA_TOUT = 0x44,
43 MCP2221_I2C_WRADDRL_NACK = 0x25,
44 MCP2221_I2C_MASK_ADDR_NACK = 0x40,
45 MCP2221_I2C_WRADDRL_SEND = 0x21,
46 MCP2221_I2C_ADDR_NACK = 0x25,
47 MCP2221_I2C_READ_COMPL = 0x55,
328de1c5
RG		 48 MCP2221_ALT_F_NOT_GPIOV = 0xEE,
49 MCP2221_ALT_F_NOT_GPIOD = 0xEF,
67a95c21
RG		 50};
51
567b8e9f
LP		 52/* MCP GPIO direction encoding */
53enum {
54 MCP2221_DIR_OUT = 0x00,
55 MCP2221_DIR_IN = 0x01,
56};
57
58#define MCP_NGPIO 4
59
60/* MCP GPIO set command layout */
61struct mcp_set_gpio {
62 u8 cmd;
63 u8 dummy;
64 struct {
65 u8 change_value;
66 u8 value;
67 u8 change_direction;
68 u8 direction;
69 } gpio[MCP_NGPIO];
70} __packed;
71
72/* MCP GPIO get command layout */
73struct mcp_get_gpio {
74 u8 cmd;
75 u8 dummy;
76 struct {
77 u8 direction;
78 u8 value;
79 } gpio[MCP_NGPIO];
80} __packed;
81
67a95c21
RG		 82/*
83 * There is no way to distinguish responses. Therefore next command
84 * is sent only after response to previous has been received. Mutex
85 * lock is used for this purpose mainly.
86 */
87struct mcp2221 {
88 struct hid_device *hdev;
89 struct i2c_adapter adapter;
90 struct mutex lock;
91 struct completion wait_in_report;
92 u8 *rxbuf;
93 u8 txbuf[64];
94 int rxbuf_idx;
95 int status;
96 u8 cur_i2c_clk_div;
328de1c5
RG		 97 struct gpio_chip *gc;
98 u8 gp_idx;
99 u8 gpio_dir;
67a95c21
RG		 100};
101
102/*
103 * Default i2c bus clock frequency 400 kHz. Modify this if you
104 * want to set some other frequency (min 50 kHz - max 400 kHz).
105 */
106static uint i2c_clk_freq = 400;
107
108/* Synchronously send output report to the device */
109static int mcp_send_report(struct mcp2221 *mcp,
110 u8 *out_report, size_t len)
111{
112 u8 *buf;
113 int ret;
114
115 buf = kmemdup(out_report, len, GFP_KERNEL);
116 if (!buf)
117 return -ENOMEM;
118
119 /* mcp2221 uses interrupt endpoint for out reports */
120 ret = hid_hw_output_report(mcp->hdev, buf, len);
121 kfree(buf);
122
123 if (ret < 0)
124 return ret;
125 return 0;
126}
127
128/*
129 * Send o/p report to the device and wait for i/p report to be
130 * received from the device. If the device does not respond,
131 * we timeout.
132 */
133static int mcp_send_data_req_status(struct mcp2221 *mcp,
134 u8 *out_report, int len)
135{
136 int ret;
137 unsigned long t;
138
139 reinit_completion(&mcp->wait_in_report);
140
141 ret = mcp_send_report(mcp, out_report, len);
142 if (ret)
143 return ret;
144
145 t = wait_for_completion_timeout(&mcp->wait_in_report,
146 msecs_to_jiffies(4000));
147 if (!t)
148 return -ETIMEDOUT;
149
150 return mcp->status;
151}
152
153/* Check pass/fail for actual communication with i2c slave */
154static int mcp_chk_last_cmd_status(struct mcp2221 *mcp)
155{
156 memset(mcp->txbuf, 0, 8);
157 mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
158
159 return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
160}
161
162/* Cancels last command releasing i2c bus just in case occupied */
163static int mcp_cancel_last_cmd(struct mcp2221 *mcp)
164{
165 memset(mcp->txbuf, 0, 8);
166 mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
167 mcp->txbuf[2] = MCP2221_I2C_CANCEL;
168
169 return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
170}
171
172static int mcp_set_i2c_speed(struct mcp2221 *mcp)
173{
174 int ret;
175
176 memset(mcp->txbuf, 0, 8);
177 mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
178 mcp->txbuf[3] = MCP2221_I2C_SET_SPEED;
179 mcp->txbuf[4] = mcp->cur_i2c_clk_div;
180
181 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 8);
182 if (ret) {
183 /* Small delay is needed here */
184 usleep_range(980, 1000);
185 mcp_cancel_last_cmd(mcp);
186 }
187
188 return 0;
189}
190
191/*
192 * An output report can contain minimum 1 and maximum 60 user data
193 * bytes. If the number of data bytes is more then 60, we send it
194 * in chunks of 60 bytes. Last chunk may contain exactly 60 or less
195 * bytes. Total number of bytes is informed in very first report to
196 * mcp2221, from that point onwards it first collect all the data
197 * from host and then send to i2c slave device.
198 */
199static int mcp_i2c_write(struct mcp2221 *mcp,
200 struct i2c_msg *msg, int type, u8 last_status)
201{
202 int ret, len, idx, sent;
203
204 idx = 0;
205 sent = 0;
206 if (msg->len < 60)
207 len = msg->len;
208 else
209 len = 60;
210
211 do {
212 mcp->txbuf[0] = type;
213 mcp->txbuf[1] = msg->len & 0xff;
214 mcp->txbuf[2] = msg->len >> 8;
215 mcp->txbuf[3] = (u8)(msg->addr << 1);
216
217 memcpy(&mcp->txbuf[4], &msg->buf[idx], len);
218
219 ret = mcp_send_data_req_status(mcp, mcp->txbuf, len + 4);
220 if (ret)
221 return ret;
222
223 usleep_range(980, 1000);
224
225 if (last_status) {
226 ret = mcp_chk_last_cmd_status(mcp);
227 if (ret)
228 return ret;
229 }
230
231 sent = sent + len;
232 if (sent >= msg->len)
233 break;
234
235 idx = idx + len;
236 if ((msg->len - sent) < 60)
237 len = msg->len - sent;
238 else
239 len = 60;
240
241 /*
242 * Testing shows delay is needed between successive writes
243 * otherwise next write fails on first-try from i2c core.
244 * This value is obtained through automated stress testing.
245 */
246 usleep_range(980, 1000);
247 } while (len > 0);
248
249 return ret;
250}
251
252/*
253 * Device reads all data (0 - 65535 bytes) from i2c slave device and
254 * stores it in device itself. This data is read back from device to
255 * host in multiples of 60 bytes using input reports.
256 */
257static int mcp_i2c_smbus_read(struct mcp2221 *mcp,
258 struct i2c_msg *msg, int type, u16 smbus_addr,
259 u8 smbus_len, u8 *smbus_buf)
260{
261 int ret;
262 u16 total_len;
263
264 mcp->txbuf[0] = type;
265 if (msg) {
266 mcp->txbuf[1] = msg->len & 0xff;
267 mcp->txbuf[2] = msg->len >> 8;
268 mcp->txbuf[3] = (u8)(msg->addr << 1);
269 total_len = msg->len;
270 mcp->rxbuf = msg->buf;
271 } else {
272 mcp->txbuf[1] = smbus_len;
273 mcp->txbuf[2] = 0;
274 mcp->txbuf[3] = (u8)(smbus_addr << 1);
275 total_len = smbus_len;
276 mcp->rxbuf = smbus_buf;
277 }
278
279 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 4);
280 if (ret)
281 return ret;
282
283 mcp->rxbuf_idx = 0;
284
285 do {
286 memset(mcp->txbuf, 0, 4);
287 mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
288
289 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
290 if (ret)
291 return ret;
292
293 ret = mcp_chk_last_cmd_status(mcp);
294 if (ret)
295 return ret;
296
297 usleep_range(980, 1000);
298 } while (mcp->rxbuf_idx < total_len);
299
300 return ret;
301}
302
303static int mcp_i2c_xfer(struct i2c_adapter *adapter,
304 struct i2c_msg msgs[], int num)
305{
306 int ret;
307 struct mcp2221 *mcp = i2c_get_adapdata(adapter);
308
309 hid_hw_power(mcp->hdev, PM_HINT_FULLON);
310
311 mutex_lock(&mcp->lock);
312
313 /* Setting speed before every transaction is required for mcp2221 */
314 ret = mcp_set_i2c_speed(mcp);
315 if (ret)
316 goto exit;
317
318 if (num == 1) {
319 if (msgs->flags & I2C_M_RD) {
320 ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA,
321 0, 0, NULL);
322 } else {
323 ret = mcp_i2c_write(mcp, msgs, MCP2221_I2C_WR_DATA, 1);
324 }
325 if (ret)
326 goto exit;
327 ret = num;
328 } else if (num == 2) {
329 /* Ex transaction; send reg address and read its contents */
330 if (msgs[0].addr == msgs[1].addr &&
331 !(msgs[0].flags & I2C_M_RD) &&
332 (msgs[1].flags & I2C_M_RD)) {
333
334 ret = mcp_i2c_write(mcp, &msgs[0],
335 MCP2221_I2C_WR_NO_STOP, 0);
336 if (ret)
337 goto exit;
338
339 ret = mcp_i2c_smbus_read(mcp, &msgs[1],
340 MCP2221_I2C_RD_RPT_START,
341 0, 0, NULL);
342 if (ret)
343 goto exit;
344 ret = num;
345 } else {
346 dev_err(&adapter->dev,
347 "unsupported multi-msg i2c transaction\n");
348 ret = -EOPNOTSUPP;
349 }
350 } else {
351 dev_err(&adapter->dev,
352 "unsupported multi-msg i2c transaction\n");
353 ret = -EOPNOTSUPP;
354 }
355
356exit:
357 hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
358 mutex_unlock(&mcp->lock);
359 return ret;
360}
361
362static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr,
363 u8 command, u8 *buf, u8 len, int type,
364 u8 last_status)
365{
366 int data_len, ret;
367
368 mcp->txbuf[0] = type;
369 mcp->txbuf[1] = len + 1; /* 1 is due to command byte itself */
370 mcp->txbuf[2] = 0;
371 mcp->txbuf[3] = (u8)(addr << 1);
372 mcp->txbuf[4] = command;
373
374 switch (len) {
375 case 0:
376 data_len = 5;
377 break;
378 case 1:
379 mcp->txbuf[5] = buf[0];
380 data_len = 6;
381 break;
382 case 2:
383 mcp->txbuf[5] = buf[0];
384 mcp->txbuf[6] = buf[1];
385 data_len = 7;
386 break;
387 default:
62ac2473
HM		 388 if (len > I2C_SMBUS_BLOCK_MAX)
389 return -EINVAL;
390
67a95c21
RG		 391 memcpy(&mcp->txbuf[5], buf, len);
392 data_len = len + 5;
393 }
394
395 ret = mcp_send_data_req_status(mcp, mcp->txbuf, data_len);
396 if (ret)
397 return ret;
398
399 if (last_status) {
400 usleep_range(980, 1000);
401
402 ret = mcp_chk_last_cmd_status(mcp);
403 if (ret)
404 return ret;
405 }
406
407 return ret;
408}
409
410static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
411 unsigned short flags, char read_write,
412 u8 command, int size,
413 union i2c_smbus_data *data)
414{
415 int ret;
416 struct mcp2221 *mcp = i2c_get_adapdata(adapter);
417
418 hid_hw_power(mcp->hdev, PM_HINT_FULLON);
419
420 mutex_lock(&mcp->lock);
421
422 ret = mcp_set_i2c_speed(mcp);
423 if (ret)
424 goto exit;
425
426 switch (size) {
427
428 case I2C_SMBUS_QUICK:
429 if (read_write == I2C_SMBUS_READ)
430 ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
431 addr, 0, &data->byte);
432 else
433 ret = mcp_smbus_write(mcp, addr, command, NULL,
434 0, MCP2221_I2C_WR_DATA, 1);
435 break;
436 case I2C_SMBUS_BYTE:
437 if (read_write == I2C_SMBUS_READ)
438 ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
439 addr, 1, &data->byte);
440 else
441 ret = mcp_smbus_write(mcp, addr, command, NULL,
442 0, MCP2221_I2C_WR_DATA, 1);
443 break;
444 case I2C_SMBUS_BYTE_DATA:
445 if (read_write == I2C_SMBUS_READ) {
446 ret = mcp_smbus_write(mcp, addr, command, NULL,
447 0, MCP2221_I2C_WR_NO_STOP, 0);
448 if (ret)
449 goto exit;
450
451 ret = mcp_i2c_smbus_read(mcp, NULL,
452 MCP2221_I2C_RD_RPT_START,
453 addr, 1, &data->byte);
454 } else {
455 ret = mcp_smbus_write(mcp, addr, command, &data->byte,
456 1, MCP2221_I2C_WR_DATA, 1);
457 }
458 break;
459 case I2C_SMBUS_WORD_DATA:
460 if (read_write == I2C_SMBUS_READ) {
461 ret = mcp_smbus_write(mcp, addr, command, NULL,
462 0, MCP2221_I2C_WR_NO_STOP, 0);
463 if (ret)
464 goto exit;
465
466 ret = mcp_i2c_smbus_read(mcp, NULL,
467 MCP2221_I2C_RD_RPT_START,
468 addr, 2, (u8 *)&data->word);
469 } else {
470 ret = mcp_smbus_write(mcp, addr, command,
471 (u8 *)&data->word, 2,
472 MCP2221_I2C_WR_DATA, 1);
473 }
474 break;
475 case I2C_SMBUS_BLOCK_DATA:
476 if (read_write == I2C_SMBUS_READ) {
477 ret = mcp_smbus_write(mcp, addr, command, NULL,
478 0, MCP2221_I2C_WR_NO_STOP, 1);
479 if (ret)
480 goto exit;
481
482 mcp->rxbuf_idx = 0;
483 mcp->rxbuf = data->block;
484 mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
485 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
486 if (ret)
487 goto exit;
488 } else {
489 if (!data->block[0]) {
490 ret = -EINVAL;
491 goto exit;
492 }
493 ret = mcp_smbus_write(mcp, addr, command, data->block,
494 data->block[0] + 1,
495 MCP2221_I2C_WR_DATA, 1);
496 }
497 break;
498 case I2C_SMBUS_I2C_BLOCK_DATA:
499 if (read_write == I2C_SMBUS_READ) {
500 ret = mcp_smbus_write(mcp, addr, command, NULL,
501 0, MCP2221_I2C_WR_NO_STOP, 1);
502 if (ret)
503 goto exit;
504
505 mcp->rxbuf_idx = 0;
506 mcp->rxbuf = data->block;
507 mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
508 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
509 if (ret)
510 goto exit;
511 } else {
512 if (!data->block[0]) {
513 ret = -EINVAL;
514 goto exit;
515 }
516 ret = mcp_smbus_write(mcp, addr, command,
517 &data->block[1], data->block[0],
518 MCP2221_I2C_WR_DATA, 1);
519 }
520 break;
521 case I2C_SMBUS_PROC_CALL:
522 ret = mcp_smbus_write(mcp, addr, command,
523 (u8 *)&data->word,
524 2, MCP2221_I2C_WR_NO_STOP, 0);
525 if (ret)
526 goto exit;
527
528 ret = mcp_i2c_smbus_read(mcp, NULL,
529 MCP2221_I2C_RD_RPT_START,
530 addr, 2, (u8 *)&data->word);
531 break;
532 case I2C_SMBUS_BLOCK_PROC_CALL:
533 ret = mcp_smbus_write(mcp, addr, command, data->block,
534 data->block[0] + 1,
535 MCP2221_I2C_WR_NO_STOP, 0);
536 if (ret)
537 goto exit;
538
539 ret = mcp_i2c_smbus_read(mcp, NULL,
540 MCP2221_I2C_RD_RPT_START,
541 addr, I2C_SMBUS_BLOCK_MAX,
542 data->block);
543 break;
544 default:
545 dev_err(&mcp->adapter.dev,
546 "unsupported smbus transaction size:%d\n", size);
547 ret = -EOPNOTSUPP;
548 }
549
550exit:
551 hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
552 mutex_unlock(&mcp->lock);
553 return ret;
554}
555
556static u32 mcp_i2c_func(struct i2c_adapter *adapter)
557{
558 return I2C_FUNC_I2C |
559 I2C_FUNC_SMBUS_READ_BLOCK_DATA |
560 I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
561 (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_PEC);
562}
563
564static const struct i2c_algorithm mcp_i2c_algo = {
565 .master_xfer = mcp_i2c_xfer,
566 .smbus_xfer = mcp_smbus_xfer,
567 .functionality = mcp_i2c_func,
568};
569
328de1c5
RG		 570static int mcp_gpio_get(struct gpio_chip *gc,
571 unsigned int offset)
572{
573 int ret;
574 struct mcp2221 *mcp = gpiochip_get_data(gc);
575
576 mcp->txbuf[0] = MCP2221_GPIO_GET;
577
567b8e9f 578 mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset].value);
328de1c5
RG		 579
580 mutex_lock(&mcp->lock);
581 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
582 mutex_unlock(&mcp->lock);
583
584 return ret;
585}
586
587static void mcp_gpio_set(struct gpio_chip *gc,
588 unsigned int offset, int value)
589{
590 struct mcp2221 *mcp = gpiochip_get_data(gc);
591
592 memset(mcp->txbuf, 0, 18);
593 mcp->txbuf[0] = MCP2221_GPIO_SET;
594
567b8e9f 595 mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].value);
328de1c5
RG		 596
597 mcp->txbuf[mcp->gp_idx - 1] = 1;
598 mcp->txbuf[mcp->gp_idx] = !!value;
599
600 mutex_lock(&mcp->lock);
601 mcp_send_data_req_status(mcp, mcp->txbuf, 18);
602 mutex_unlock(&mcp->lock);
603}
604
605static int mcp_gpio_dir_set(struct mcp2221 *mcp,
606 unsigned int offset, u8 val)
607{
608 memset(mcp->txbuf, 0, 18);
609 mcp->txbuf[0] = MCP2221_GPIO_SET;
610
567b8e9f 611 mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].direction);
328de1c5
RG		 612
613 mcp->txbuf[mcp->gp_idx - 1] = 1;
614 mcp->txbuf[mcp->gp_idx] = val;
615
616 return mcp_send_data_req_status(mcp, mcp->txbuf, 18);
617}
618
619static int mcp_gpio_direction_input(struct gpio_chip *gc,
620 unsigned int offset)
621{
622 int ret;
623 struct mcp2221 *mcp = gpiochip_get_data(gc);
624
625 mutex_lock(&mcp->lock);
567b8e9f 626 ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_IN);
328de1c5
RG		 627 mutex_unlock(&mcp->lock);
628
629 return ret;
630}
631
632static int mcp_gpio_direction_output(struct gpio_chip *gc,
633 unsigned int offset, int value)
634{
635 int ret;
636 struct mcp2221 *mcp = gpiochip_get_data(gc);
637
638 mutex_lock(&mcp->lock);
567b8e9f 639 ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_OUT);
328de1c5
RG		 640 mutex_unlock(&mcp->lock);
641
642 /* Can't configure as output, bailout early */
643 if (ret)
644 return ret;
645
646 mcp_gpio_set(gc, offset, value);
647
648 return 0;
649}
650
651static int mcp_gpio_get_direction(struct gpio_chip *gc,
652 unsigned int offset)
653{
654 int ret;
655 struct mcp2221 *mcp = gpiochip_get_data(gc);
656
657 mcp->txbuf[0] = MCP2221_GPIO_GET;
658
567b8e9f 659 mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset].direction);
328de1c5
RG		 660
661 mutex_lock(&mcp->lock);
662 ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
663 mutex_unlock(&mcp->lock);
664
665 if (ret)
666 return ret;
667
567b8e9f 668 if (mcp->gpio_dir == MCP2221_DIR_IN)
328de1c5
RG		 669 return GPIO_LINE_DIRECTION_IN;
670
671 return GPIO_LINE_DIRECTION_OUT;
672}
673
67a95c21
RG		 674/* Gives current state of i2c engine inside mcp2221 */
675static int mcp_get_i2c_eng_state(struct mcp2221 *mcp,
676 u8 *data, u8 idx)
677{
678 int ret;
679
680 switch (data[idx]) {
681 case MCP2221_I2C_WRADDRL_NACK:
682 case MCP2221_I2C_WRADDRL_SEND:
683 ret = -ENXIO;
684 break;
685 case MCP2221_I2C_START_TOUT:
686 case MCP2221_I2C_STOP_TOUT:
687 case MCP2221_I2C_WRADDRL_TOUT:
688 case MCP2221_I2C_WRDATA_TOUT:
689 ret = -ETIMEDOUT;
690 break;
691 case MCP2221_I2C_ENG_BUSY:
692 ret = -EAGAIN;
693 break;
694 case MCP2221_SUCCESS:
695 ret = 0x00;
696 break;
697 default:
698 ret = -EIO;
699 }
700
701 return ret;
702}
703
704/*
705 * MCP2221 uses interrupt endpoint for input reports. This function
706 * is called by HID layer when it receives i/p report from mcp2221,
707 * which is actually a response to the previously sent command.
708 *
709 * MCP2221A firmware specific return codes are parsed and 0 or
710 * appropriate negative error code is returned. Delayed response
711 * results in timeout error and stray reponses results in -EIO.
712 */
713static int mcp2221_raw_event(struct hid_device *hdev,
714 struct hid_report *report, u8 *data, int size)
715{
716 u8 *buf;
717 struct mcp2221 *mcp = hid_get_drvdata(hdev);
718
719 switch (data[0]) {
720
721 case MCP2221_I2C_WR_DATA:
722 case MCP2221_I2C_WR_NO_STOP:
723 case MCP2221_I2C_RD_DATA:
724 case MCP2221_I2C_RD_RPT_START:
725 switch (data[1]) {
726 case MCP2221_SUCCESS:
727 mcp->status = 0;
728 break;
729 default:
730 mcp->status = mcp_get_i2c_eng_state(mcp, data, 2);
731 }
732 complete(&mcp->wait_in_report);
733 break;
734
735 case MCP2221_I2C_PARAM_OR_STATUS:
736 switch (data[1]) {
737 case MCP2221_SUCCESS:
738 if ((mcp->txbuf[3] == MCP2221_I2C_SET_SPEED) &&
739 (data[3] != MCP2221_I2C_SET_SPEED)) {
740 mcp->status = -EAGAIN;
741 break;
742 }
743 if (data[20] & MCP2221_I2C_MASK_ADDR_NACK) {
744 mcp->status = -ENXIO;
745 break;
746 }
747 mcp->status = mcp_get_i2c_eng_state(mcp, data, 8);
748 break;
749 default:
750 mcp->status = -EIO;
751 }
752 complete(&mcp->wait_in_report);
753 break;
754
755 case MCP2221_I2C_GET_DATA:
756 switch (data[1]) {
757 case MCP2221_SUCCESS:
758 if (data[2] == MCP2221_I2C_ADDR_NACK) {
759 mcp->status = -ENXIO;
760 break;
761 }
762 if (!mcp_get_i2c_eng_state(mcp, data, 2)
763 && (data[3] == 0)) {
764 mcp->status = 0;
765 break;
766 }
767 if (data[3] == 127) {
768 mcp->status = -EIO;
769 break;
770 }
771 if (data[2] == MCP2221_I2C_READ_COMPL) {
772 buf = mcp->rxbuf;
773 memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]);
774 mcp->rxbuf_idx = mcp->rxbuf_idx + data[3];
775 mcp->status = 0;
776 break;
777 }
778 mcp->status = -EIO;
779 break;
780 default:
781 mcp->status = -EIO;
782 }
783 complete(&mcp->wait_in_report);
784 break;
785
328de1c5
RG		 786 case MCP2221_GPIO_GET:
787 switch (data[1]) {
788 case MCP2221_SUCCESS:
789 if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
790 (data[mcp->gp_idx + 1] == MCP2221_ALT_F_NOT_GPIOD)) {
791 mcp->status = -ENOENT;
792 } else {
793 mcp->status = !!data[mcp->gp_idx];
567b8e9f 794 mcp->gpio_dir = data[mcp->gp_idx + 1];
328de1c5
RG		 795 }
796 break;
797 default:
798 mcp->status = -EAGAIN;
799 }
800 complete(&mcp->wait_in_report);
801 break;
802
803 case MCP2221_GPIO_SET:
804 switch (data[1]) {
805 case MCP2221_SUCCESS:
806 if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
807 (data[mcp->gp_idx - 1] == MCP2221_ALT_F_NOT_GPIOV)) {
808 mcp->status = -ENOENT;
809 } else {
810 mcp->status = 0;
811 }
812 break;
813 default:
814 mcp->status = -EAGAIN;
815 }
816 complete(&mcp->wait_in_report);
817 break;
818
67a95c21
RG		 819 default:
820 mcp->status = -EIO;
821 complete(&mcp->wait_in_report);
822 }
823
824 return 1;
825}
826
827static int mcp2221_probe(struct hid_device *hdev,
828 const struct hid_device_id *id)
829{
830 int ret;
831 struct mcp2221 *mcp;
832
833 mcp = devm_kzalloc(&hdev->dev, sizeof(*mcp), GFP_KERNEL);
834 if (!mcp)
835 return -ENOMEM;
836
837 ret = hid_parse(hdev);
838 if (ret) {
839 hid_err(hdev, "can't parse reports\n");
840 return ret;
841 }
842
843 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
844 if (ret) {
845 hid_err(hdev, "can't start hardware\n");
846 return ret;
847 }
848
849 ret = hid_hw_open(hdev);
850 if (ret) {
851 hid_err(hdev, "can't open device\n");
852 goto err_hstop;
853 }
854
855 mutex_init(&mcp->lock);
856 init_completion(&mcp->wait_in_report);
857 hid_set_drvdata(hdev, mcp);
858 mcp->hdev = hdev;
859
860 /* Set I2C bus clock diviser */
861 if (i2c_clk_freq > 400)
862 i2c_clk_freq = 400;
863 if (i2c_clk_freq < 50)
864 i2c_clk_freq = 50;
865 mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3;
866
867 mcp->adapter.owner = THIS_MODULE;
868 mcp->adapter.class = I2C_CLASS_HWMON;
869 mcp->adapter.algo = &mcp_i2c_algo;
870 mcp->adapter.retries = 1;
871 mcp->adapter.dev.parent = &hdev->dev;
872 snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
873 "MCP2221 usb-i2c bridge on hidraw%d",
874 ((struct hidraw *)hdev->hidraw)->minor);
875
876 ret = i2c_add_adapter(&mcp->adapter);
877 if (ret) {
878 hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret);
879 goto err_i2c;
880 }
881 i2c_set_adapdata(&mcp->adapter, mcp);
882
328de1c5
RG		 883 /* Setup GPIO chip */
884 mcp->gc = devm_kzalloc(&hdev->dev, sizeof(*mcp->gc), GFP_KERNEL);
885 if (!mcp->gc) {
886 ret = -ENOMEM;
887 goto err_gc;
888 }
889
890 mcp->gc->label = "mcp2221_gpio";
891 mcp->gc->direction_input = mcp_gpio_direction_input;
892 mcp->gc->direction_output = mcp_gpio_direction_output;
893 mcp->gc->get_direction = mcp_gpio_get_direction;
894 mcp->gc->set = mcp_gpio_set;
895 mcp->gc->get = mcp_gpio_get;
567b8e9f 896 mcp->gc->ngpio = MCP_NGPIO;
328de1c5
RG		 897 mcp->gc->base = -1;
898 mcp->gc->can_sleep = 1;
899 mcp->gc->parent = &hdev->dev;
900
901 ret = devm_gpiochip_add_data(&hdev->dev, mcp->gc, mcp);
902 if (ret)
903 goto err_gc;
904
67a95c21
RG		 905 return 0;
906
328de1c5
RG		 907err_gc:
908 i2c_del_adapter(&mcp->adapter);
67a95c21
RG		 909err_i2c:
910 hid_hw_close(mcp->hdev);
911err_hstop:
912 hid_hw_stop(mcp->hdev);
913 return ret;
914}
915
916static void mcp2221_remove(struct hid_device *hdev)
917{
918 struct mcp2221 *mcp = hid_get_drvdata(hdev);
919
920 i2c_del_adapter(&mcp->adapter);
921 hid_hw_close(mcp->hdev);
922 hid_hw_stop(mcp->hdev);
923}
924
925static const struct hid_device_id mcp2221_devices[] = {
926 { HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_MCP2221) },
927 { }
928};
929MODULE_DEVICE_TABLE(hid, mcp2221_devices);
930
931static struct hid_driver mcp2221_driver = {
932 .name = "mcp2221",
933 .id_table = mcp2221_devices,
934 .probe = mcp2221_probe,
935 .remove = mcp2221_remove,
936 .raw_event = mcp2221_raw_event,
937};
938
939/* Register with HID core */
940module_hid_driver(mcp2221_driver);
941
942MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
943MODULE_DESCRIPTION("MCP2221 Microchip HID USB to I2C master bridge");
944MODULE_LICENSE("GPL v2");
Linux 6.x block layer and io_uring tree(s)