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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
4 * Copyright (c) 2013,2014 Uplogix, Inc.
5 * David Barksdale <dbarksdale@uplogix.com>
6 */
7
8/*
9 * The Silicon Labs CP2112 chip is a USB HID device which provides an
10 * SMBus controller for talking to slave devices and 8 GPIO pins. The
11 * host communicates with the CP2112 via raw HID reports.
12 *
13 * Data Sheet:
14 * https://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
15 * Programming Interface Specification:
16 * https://www.silabs.com/documents/public/application-notes/an495-cp2112-interface-specification.pdf
17 */
18
19#include <linux/bitops.h>
20#include <linux/gpio/driver.h>
21#include <linux/hid.h>
22#include <linux/hidraw.h>
23#include <linux/i2c.h>
24#include <linux/module.h>
25#include <linux/nls.h>
26#include <linux/string_choices.h>
27#include <linux/usb/ch9.h>
28#include "hid-ids.h"
29
30#define CP2112_REPORT_MAX_LENGTH 64
31#define CP2112_GPIO_CONFIG_LENGTH 5
32#define CP2112_GPIO_GET_LENGTH 2
33#define CP2112_GPIO_SET_LENGTH 3
34#define CP2112_GPIO_MAX_GPIO 8
35#define CP2112_GPIO_ALL_GPIO_MASK GENMASK(7, 0)
36
37enum {
38 CP2112_GPIO_CONFIG = 0x02,
39 CP2112_GPIO_GET = 0x03,
40 CP2112_GPIO_SET = 0x04,
41 CP2112_GET_VERSION_INFO = 0x05,
42 CP2112_SMBUS_CONFIG = 0x06,
43 CP2112_DATA_READ_REQUEST = 0x10,
44 CP2112_DATA_WRITE_READ_REQUEST = 0x11,
45 CP2112_DATA_READ_FORCE_SEND = 0x12,
46 CP2112_DATA_READ_RESPONSE = 0x13,
47 CP2112_DATA_WRITE_REQUEST = 0x14,
48 CP2112_TRANSFER_STATUS_REQUEST = 0x15,
49 CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
50 CP2112_CANCEL_TRANSFER = 0x17,
51 CP2112_LOCK_BYTE = 0x20,
52 CP2112_USB_CONFIG = 0x21,
53 CP2112_MANUFACTURER_STRING = 0x22,
54 CP2112_PRODUCT_STRING = 0x23,
55 CP2112_SERIAL_STRING = 0x24,
56};
57
58enum {
59 STATUS0_IDLE = 0x00,
60 STATUS0_BUSY = 0x01,
61 STATUS0_COMPLETE = 0x02,
62 STATUS0_ERROR = 0x03,
63};
64
65enum {
66 STATUS1_TIMEOUT_NACK = 0x00,
67 STATUS1_TIMEOUT_BUS = 0x01,
68 STATUS1_ARBITRATION_LOST = 0x02,
69 STATUS1_READ_INCOMPLETE = 0x03,
70 STATUS1_WRITE_INCOMPLETE = 0x04,
71 STATUS1_SUCCESS = 0x05,
72};
73
74struct cp2112_smbus_config_report {
75 u8 report; /* CP2112_SMBUS_CONFIG */
76 __be32 clock_speed; /* Hz */
77 u8 device_address; /* Stored in the upper 7 bits */
78 u8 auto_send_read; /* 1 = enabled, 0 = disabled */
79 __be16 write_timeout; /* ms, 0 = no timeout */
80 __be16 read_timeout; /* ms, 0 = no timeout */
81 u8 scl_low_timeout; /* 1 = enabled, 0 = disabled */
82 __be16 retry_time; /* # of retries, 0 = no limit */
83} __packed;
84
85struct cp2112_usb_config_report {
86 u8 report; /* CP2112_USB_CONFIG */
87 __le16 vid; /* Vendor ID */
88 __le16 pid; /* Product ID */
89 u8 max_power; /* Power requested in 2mA units */
90 u8 power_mode; /* 0x00 = bus powered
91 0x01 = self powered & regulator off
92 0x02 = self powered & regulator on */
93 u8 release_major;
94 u8 release_minor;
95 u8 mask; /* What fields to program */
96} __packed;
97
98struct cp2112_read_req_report {
99 u8 report; /* CP2112_DATA_READ_REQUEST */
100 u8 slave_address;
101 __be16 length;
102} __packed;
103
104struct cp2112_write_read_req_report {
105 u8 report; /* CP2112_DATA_WRITE_READ_REQUEST */
106 u8 slave_address;
107 __be16 length;
108 u8 target_address_length;
109 u8 target_address[16];
110} __packed;
111
112struct cp2112_write_req_report {
113 u8 report; /* CP2112_DATA_WRITE_REQUEST */
114 u8 slave_address;
115 u8 length;
116 u8 data[61];
117} __packed;
118
119struct cp2112_force_read_report {
120 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
121 __be16 length;
122} __packed;
123
124struct cp2112_xfer_status_report {
125 u8 report; /* CP2112_TRANSFER_STATUS_RESPONSE */
126 u8 status0; /* STATUS0_* */
127 u8 status1; /* STATUS1_* */
128 __be16 retries;
129 __be16 length;
130} __packed;
131
132struct cp2112_string_report {
133 u8 dummy; /* force .string to be aligned */
134 struct_group_attr(contents, __packed,
135 u8 report; /* CP2112_*_STRING */
136 u8 length; /* length in bytes of everything after .report */
137 u8 type; /* USB_DT_STRING */
138 wchar_t string[30]; /* UTF16_LITTLE_ENDIAN string */
139 );
140} __packed;
141
142/* Number of times to request transfer status before giving up waiting for a
143 transfer to complete. This may need to be changed if SMBUS clock, retries,
144 or read/write/scl_low timeout settings are changed. */
145static const int XFER_STATUS_RETRIES = 10;
146
147/* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
148 CP2112_TRANSFER_STATUS_RESPONSE. */
149static const int RESPONSE_TIMEOUT = 50;
150
151static const struct hid_device_id cp2112_devices[] = {
152 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
153 { }
154};
155MODULE_DEVICE_TABLE(hid, cp2112_devices);
156
157struct cp2112_device {
158 struct i2c_adapter adap;
159 struct hid_device *hdev;
160 wait_queue_head_t wait;
161 u8 read_data[61];
162 u8 read_length;
163 u8 hwversion;
164 int xfer_status;
165 atomic_t read_avail;
166 atomic_t xfer_avail;
167 struct gpio_chip gc;
168 u8 *in_out_buffer;
169 struct mutex lock;
170
171 bool gpio_poll;
172 struct delayed_work gpio_poll_worker;
173 unsigned long irq_mask;
174 u8 gpio_prev_state;
175};
176
177static int gpio_push_pull = CP2112_GPIO_ALL_GPIO_MASK;
178module_param(gpio_push_pull, int, 0644);
179MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
180
181static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
182{
183 struct cp2112_device *dev = gpiochip_get_data(chip);
184 struct hid_device *hdev = dev->hdev;
185 u8 *buf = dev->in_out_buffer;
186 int ret;
187
188 mutex_lock(&dev->lock);
189
190 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
191 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
192 HID_REQ_GET_REPORT);
193 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
194 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
195 if (ret >= 0)
196 ret = -EIO;
197 goto exit;
198 }
199
200 buf[1] &= ~BIT(offset);
201 buf[2] = gpio_push_pull;
202
203 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
204 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
205 HID_REQ_SET_REPORT);
206 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
207 hid_err(hdev, "error setting GPIO config: %d\n", ret);
208 if (ret >= 0)
209 ret = -EIO;
210 goto exit;
211 }
212
213 ret = 0;
214
215exit:
216 mutex_unlock(&dev->lock);
217 return ret;
218}
219
220static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
221{
222 struct cp2112_device *dev = gpiochip_get_data(chip);
223 struct hid_device *hdev = dev->hdev;
224 u8 *buf = dev->in_out_buffer;
225 int ret;
226
227 mutex_lock(&dev->lock);
228
229 buf[0] = CP2112_GPIO_SET;
230 buf[1] = value ? CP2112_GPIO_ALL_GPIO_MASK : 0;
231 buf[2] = BIT(offset);
232
233 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
234 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
235 HID_REQ_SET_REPORT);
236 if (ret < 0)
237 hid_err(hdev, "error setting GPIO values: %d\n", ret);
238
239 mutex_unlock(&dev->lock);
240}
241
242static int cp2112_gpio_get_all(struct gpio_chip *chip)
243{
244 struct cp2112_device *dev = gpiochip_get_data(chip);
245 struct hid_device *hdev = dev->hdev;
246 u8 *buf = dev->in_out_buffer;
247 int ret;
248
249 mutex_lock(&dev->lock);
250
251 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
252 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
253 HID_REQ_GET_REPORT);
254 if (ret != CP2112_GPIO_GET_LENGTH) {
255 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
256 ret = ret < 0 ? ret : -EIO;
257 goto exit;
258 }
259
260 ret = buf[1];
261
262exit:
263 mutex_unlock(&dev->lock);
264
265 return ret;
266}
267
268static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
269{
270 int ret;
271
272 ret = cp2112_gpio_get_all(chip);
273 if (ret < 0)
274 return ret;
275
276 return (ret >> offset) & 1;
277}
278
279static int cp2112_gpio_direction_output(struct gpio_chip *chip,
280 unsigned offset, int value)
281{
282 struct cp2112_device *dev = gpiochip_get_data(chip);
283 struct hid_device *hdev = dev->hdev;
284 u8 *buf = dev->in_out_buffer;
285 int ret;
286
287 mutex_lock(&dev->lock);
288
289 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
290 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
291 HID_REQ_GET_REPORT);
292 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
293 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
294 goto fail;
295 }
296
297 buf[1] |= 1 << offset;
298 buf[2] = gpio_push_pull;
299
300 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
301 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
302 HID_REQ_SET_REPORT);
303 if (ret < 0) {
304 hid_err(hdev, "error setting GPIO config: %d\n", ret);
305 goto fail;
306 }
307
308 mutex_unlock(&dev->lock);
309
310 /*
311 * Set gpio value when output direction is already set,
312 * as specified in AN495, Rev. 0.2, cpt. 4.4
313 */
314 cp2112_gpio_set(chip, offset, value);
315
316 return 0;
317
318fail:
319 mutex_unlock(&dev->lock);
320 return ret < 0 ? ret : -EIO;
321}
322
323static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
324 u8 *data, size_t count, unsigned char report_type)
325{
326 u8 *buf;
327 int ret;
328
329 buf = kmalloc(count, GFP_KERNEL);
330 if (!buf)
331 return -ENOMEM;
332
333 ret = hid_hw_raw_request(hdev, report_number, buf, count,
334 report_type, HID_REQ_GET_REPORT);
335 memcpy(data, buf, count);
336 kfree(buf);
337 return ret;
338}
339
340static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
341 unsigned char report_type)
342{
343 u8 *buf;
344 int ret;
345
346 buf = kmemdup(data, count, GFP_KERNEL);
347 if (!buf)
348 return -ENOMEM;
349
350 if (report_type == HID_OUTPUT_REPORT)
351 ret = hid_hw_output_report(hdev, buf, count);
352 else
353 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
354 HID_REQ_SET_REPORT);
355
356 kfree(buf);
357 return ret;
358}
359
360static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
361{
362 int ret = 0;
363
364 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
365 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
366 * come in cp2112_raw_event or timeout. There will only be one of these
367 * in flight at any one time. The timeout is extremely large and is a
368 * last resort if the CP2112 has died. If we do timeout we don't expect
369 * to receive the response which would cause data races, it's not like
370 * we can do anything about it anyway.
371 */
372 ret = wait_event_interruptible_timeout(dev->wait,
373 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
374 if (-ERESTARTSYS == ret)
375 return ret;
376 if (!ret)
377 return -ETIMEDOUT;
378
379 atomic_set(avail, 0);
380 return 0;
381}
382
383static int cp2112_xfer_status(struct cp2112_device *dev)
384{
385 struct hid_device *hdev = dev->hdev;
386 u8 buf[2];
387 int ret;
388
389 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
390 buf[1] = 0x01;
391 atomic_set(&dev->xfer_avail, 0);
392
393 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
394 if (ret < 0) {
395 hid_warn(hdev, "Error requesting status: %d\n", ret);
396 return ret;
397 }
398
399 ret = cp2112_wait(dev, &dev->xfer_avail);
400 if (ret)
401 return ret;
402
403 return dev->xfer_status;
404}
405
406static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
407{
408 struct hid_device *hdev = dev->hdev;
409 struct cp2112_force_read_report report;
410 int ret;
411
412 if (size > sizeof(dev->read_data))
413 size = sizeof(dev->read_data);
414 report.report = CP2112_DATA_READ_FORCE_SEND;
415 report.length = cpu_to_be16(size);
416
417 atomic_set(&dev->read_avail, 0);
418
419 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
420 HID_OUTPUT_REPORT);
421 if (ret < 0) {
422 hid_warn(hdev, "Error requesting data: %d\n", ret);
423 return ret;
424 }
425
426 ret = cp2112_wait(dev, &dev->read_avail);
427 if (ret)
428 return ret;
429
430 hid_dbg(hdev, "read %d of %zd bytes requested\n",
431 dev->read_length, size);
432
433 if (size > dev->read_length)
434 size = dev->read_length;
435
436 memcpy(data, dev->read_data, size);
437 return dev->read_length;
438}
439
440static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
441{
442 struct cp2112_read_req_report *report = buf;
443
444 if (length < 1 || length > 512)
445 return -EINVAL;
446
447 report->report = CP2112_DATA_READ_REQUEST;
448 report->slave_address = slave_address << 1;
449 report->length = cpu_to_be16(length);
450 return sizeof(*report);
451}
452
453static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
454 u8 command, u8 *data, u8 data_length)
455{
456 struct cp2112_write_read_req_report *report = buf;
457
458 if (length < 1 || length > 512
459 || data_length > sizeof(report->target_address) - 1)
460 return -EINVAL;
461
462 report->report = CP2112_DATA_WRITE_READ_REQUEST;
463 report->slave_address = slave_address << 1;
464 report->length = cpu_to_be16(length);
465 report->target_address_length = data_length + 1;
466 report->target_address[0] = command;
467 memcpy(&report->target_address[1], data, data_length);
468 return data_length + 6;
469}
470
471static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
472 u8 data_length)
473{
474 struct cp2112_write_req_report *report = buf;
475
476 if (data_length > sizeof(report->data) - 1)
477 return -EINVAL;
478
479 report->report = CP2112_DATA_WRITE_REQUEST;
480 report->slave_address = slave_address << 1;
481 report->length = data_length + 1;
482 report->data[0] = command;
483 memcpy(&report->data[1], data, data_length);
484 return data_length + 4;
485}
486
487static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
488 u8 data_length)
489{
490 struct cp2112_write_req_report *report = buf;
491
492 if (data_length > sizeof(report->data))
493 return -EINVAL;
494
495 report->report = CP2112_DATA_WRITE_REQUEST;
496 report->slave_address = slave_address << 1;
497 report->length = data_length;
498 memcpy(report->data, data, data_length);
499 return data_length + 3;
500}
501
502static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
503 u8 *addr, int addr_length,
504 int read_length)
505{
506 struct cp2112_write_read_req_report *report = buf;
507
508 if (read_length < 1 || read_length > 512 ||
509 addr_length > sizeof(report->target_address))
510 return -EINVAL;
511
512 report->report = CP2112_DATA_WRITE_READ_REQUEST;
513 report->slave_address = slave_address << 1;
514 report->length = cpu_to_be16(read_length);
515 report->target_address_length = addr_length;
516 memcpy(report->target_address, addr, addr_length);
517 return addr_length + 5;
518}
519
520static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
521 int num)
522{
523 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
524 struct hid_device *hdev = dev->hdev;
525 u8 buf[64];
526 ssize_t count;
527 ssize_t read_length = 0;
528 u8 *read_buf = NULL;
529 unsigned int retries;
530 int ret;
531
532 hid_dbg(hdev, "I2C %d messages\n", num);
533
534 if (num == 1) {
535 hid_dbg(hdev, "I2C %s %#04x len %d\n",
536 str_read_write(msgs->flags & I2C_M_RD), msgs->addr, msgs->len);
537 if (msgs->flags & I2C_M_RD) {
538 read_length = msgs->len;
539 read_buf = msgs->buf;
540 count = cp2112_read_req(buf, msgs->addr, msgs->len);
541 } else {
542 count = cp2112_i2c_write_req(buf, msgs->addr,
543 msgs->buf, msgs->len);
544 }
545 if (count < 0)
546 return count;
547 } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */
548 num == 2 &&
549 msgs[0].addr == msgs[1].addr &&
550 !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
551 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
552 msgs[0].addr, msgs[0].len, msgs[1].len);
553 read_length = msgs[1].len;
554 read_buf = msgs[1].buf;
555 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
556 msgs[0].buf, msgs[0].len, msgs[1].len);
557 if (count < 0)
558 return count;
559 } else {
560 hid_err(hdev,
561 "Multi-message I2C transactions not supported\n");
562 return -EOPNOTSUPP;
563 }
564
565 ret = hid_hw_power(hdev, PM_HINT_FULLON);
566 if (ret < 0) {
567 hid_err(hdev, "power management error: %d\n", ret);
568 return ret;
569 }
570
571 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
572 if (ret < 0) {
573 hid_warn(hdev, "Error starting transaction: %d\n", ret);
574 goto power_normal;
575 }
576
577 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
578 ret = cp2112_xfer_status(dev);
579 if (-EBUSY == ret)
580 continue;
581 if (ret < 0)
582 goto power_normal;
583 break;
584 }
585
586 if (XFER_STATUS_RETRIES <= retries) {
587 hid_warn(hdev, "Transfer timed out, cancelling.\n");
588 buf[0] = CP2112_CANCEL_TRANSFER;
589 buf[1] = 0x01;
590
591 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
592 if (ret < 0)
593 hid_warn(hdev, "Error cancelling transaction: %d\n",
594 ret);
595
596 ret = -ETIMEDOUT;
597 goto power_normal;
598 }
599
600 for (count = 0; count < read_length;) {
601 ret = cp2112_read(dev, read_buf + count, read_length - count);
602 if (ret < 0)
603 goto power_normal;
604 if (ret == 0) {
605 hid_err(hdev, "read returned 0\n");
606 ret = -EIO;
607 goto power_normal;
608 }
609 count += ret;
610 if (count > read_length) {
611 /*
612 * The hardware returned too much data.
613 * This is mostly harmless because cp2112_read()
614 * has a limit check so didn't overrun our
615 * buffer. Nevertheless, we return an error
616 * because something is seriously wrong and
617 * it shouldn't go unnoticed.
618 */
619 hid_err(hdev, "long read: %d > %zd\n",
620 ret, read_length - count + ret);
621 ret = -EIO;
622 goto power_normal;
623 }
624 }
625
626 /* return the number of transferred messages */
627 ret = num;
628
629power_normal:
630 hid_hw_power(hdev, PM_HINT_NORMAL);
631 hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
632 return ret;
633}
634
635static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
636 unsigned short flags, char read_write, u8 command,
637 int size, union i2c_smbus_data *data)
638{
639 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
640 struct hid_device *hdev = dev->hdev;
641 u8 buf[64];
642 __le16 word;
643 ssize_t count;
644 size_t read_length = 0;
645 unsigned int retries;
646 int ret;
647
648 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
649 str_write_read(read_write == I2C_SMBUS_WRITE),
650 addr, flags, command, size);
651
652 switch (size) {
653 case I2C_SMBUS_BYTE:
654 read_length = 1;
655
656 if (I2C_SMBUS_READ == read_write)
657 count = cp2112_read_req(buf, addr, read_length);
658 else
659 count = cp2112_write_req(buf, addr, command, NULL,
660 0);
661 break;
662 case I2C_SMBUS_BYTE_DATA:
663 read_length = 1;
664
665 if (I2C_SMBUS_READ == read_write)
666 count = cp2112_write_read_req(buf, addr, read_length,
667 command, NULL, 0);
668 else
669 count = cp2112_write_req(buf, addr, command,
670 &data->byte, 1);
671 break;
672 case I2C_SMBUS_WORD_DATA:
673 read_length = 2;
674 word = cpu_to_le16(data->word);
675
676 if (I2C_SMBUS_READ == read_write)
677 count = cp2112_write_read_req(buf, addr, read_length,
678 command, NULL, 0);
679 else
680 count = cp2112_write_req(buf, addr, command,
681 (u8 *)&word, 2);
682 break;
683 case I2C_SMBUS_PROC_CALL:
684 size = I2C_SMBUS_WORD_DATA;
685 read_write = I2C_SMBUS_READ;
686 read_length = 2;
687 word = cpu_to_le16(data->word);
688
689 count = cp2112_write_read_req(buf, addr, read_length, command,
690 (u8 *)&word, 2);
691 break;
692 case I2C_SMBUS_I2C_BLOCK_DATA:
693 if (read_write == I2C_SMBUS_READ) {
694 read_length = data->block[0];
695 count = cp2112_write_read_req(buf, addr, read_length,
696 command, NULL, 0);
697 } else {
698 count = cp2112_write_req(buf, addr, command,
699 data->block + 1,
700 data->block[0]);
701 }
702 break;
703 case I2C_SMBUS_BLOCK_DATA:
704 if (I2C_SMBUS_READ == read_write) {
705 count = cp2112_write_read_req(buf, addr,
706 I2C_SMBUS_BLOCK_MAX,
707 command, NULL, 0);
708 } else {
709 count = cp2112_write_req(buf, addr, command,
710 data->block,
711 data->block[0] + 1);
712 }
713 break;
714 case I2C_SMBUS_BLOCK_PROC_CALL:
715 size = I2C_SMBUS_BLOCK_DATA;
716 read_write = I2C_SMBUS_READ;
717
718 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
719 command, data->block,
720 data->block[0] + 1);
721 break;
722 default:
723 hid_warn(hdev, "Unsupported transaction %d\n", size);
724 return -EOPNOTSUPP;
725 }
726
727 if (count < 0)
728 return count;
729
730 ret = hid_hw_power(hdev, PM_HINT_FULLON);
731 if (ret < 0) {
732 hid_err(hdev, "power management error: %d\n", ret);
733 return ret;
734 }
735
736 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
737 if (ret < 0) {
738 hid_warn(hdev, "Error starting transaction: %d\n", ret);
739 goto power_normal;
740 }
741
742 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
743 ret = cp2112_xfer_status(dev);
744 if (-EBUSY == ret)
745 continue;
746 if (ret < 0)
747 goto power_normal;
748 break;
749 }
750
751 if (XFER_STATUS_RETRIES <= retries) {
752 hid_warn(hdev, "Transfer timed out, cancelling.\n");
753 buf[0] = CP2112_CANCEL_TRANSFER;
754 buf[1] = 0x01;
755
756 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
757 if (ret < 0)
758 hid_warn(hdev, "Error cancelling transaction: %d\n",
759 ret);
760
761 ret = -ETIMEDOUT;
762 goto power_normal;
763 }
764
765 if (I2C_SMBUS_WRITE == read_write) {
766 ret = 0;
767 goto power_normal;
768 }
769
770 if (I2C_SMBUS_BLOCK_DATA == size)
771 read_length = ret;
772
773 ret = cp2112_read(dev, buf, read_length);
774 if (ret < 0)
775 goto power_normal;
776 if (ret != read_length) {
777 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
778 ret = -EIO;
779 goto power_normal;
780 }
781
782 switch (size) {
783 case I2C_SMBUS_BYTE:
784 case I2C_SMBUS_BYTE_DATA:
785 data->byte = buf[0];
786 break;
787 case I2C_SMBUS_WORD_DATA:
788 data->word = le16_to_cpup((__le16 *)buf);
789 break;
790 case I2C_SMBUS_I2C_BLOCK_DATA:
791 if (read_length > I2C_SMBUS_BLOCK_MAX) {
792 ret = -EINVAL;
793 goto power_normal;
794 }
795
796 memcpy(data->block + 1, buf, read_length);
797 break;
798 case I2C_SMBUS_BLOCK_DATA:
799 if (read_length > I2C_SMBUS_BLOCK_MAX) {
800 ret = -EPROTO;
801 goto power_normal;
802 }
803
804 memcpy(data->block, buf, read_length);
805 break;
806 }
807
808 ret = 0;
809power_normal:
810 hid_hw_power(hdev, PM_HINT_NORMAL);
811 hid_dbg(hdev, "transfer finished: %d\n", ret);
812 return ret;
813}
814
815static u32 cp2112_functionality(struct i2c_adapter *adap)
816{
817 return I2C_FUNC_I2C |
818 I2C_FUNC_SMBUS_BYTE |
819 I2C_FUNC_SMBUS_BYTE_DATA |
820 I2C_FUNC_SMBUS_WORD_DATA |
821 I2C_FUNC_SMBUS_BLOCK_DATA |
822 I2C_FUNC_SMBUS_I2C_BLOCK |
823 I2C_FUNC_SMBUS_PROC_CALL |
824 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
825}
826
827static const struct i2c_algorithm smbus_algorithm = {
828 .master_xfer = cp2112_i2c_xfer,
829 .smbus_xfer = cp2112_xfer,
830 .functionality = cp2112_functionality,
831};
832
833static int cp2112_get_usb_config(struct hid_device *hdev,
834 struct cp2112_usb_config_report *cfg)
835{
836 int ret;
837
838 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
839 HID_FEATURE_REPORT);
840 if (ret != sizeof(*cfg)) {
841 hid_err(hdev, "error reading usb config: %d\n", ret);
842 if (ret < 0)
843 return ret;
844 return -EIO;
845 }
846
847 return 0;
848}
849
850static int cp2112_set_usb_config(struct hid_device *hdev,
851 struct cp2112_usb_config_report *cfg)
852{
853 int ret;
854
855 BUG_ON(cfg->report != CP2112_USB_CONFIG);
856
857 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
858 HID_FEATURE_REPORT);
859 if (ret != sizeof(*cfg)) {
860 hid_err(hdev, "error writing usb config: %d\n", ret);
861 if (ret < 0)
862 return ret;
863 return -EIO;
864 }
865
866 return 0;
867}
868
869static void chmod_sysfs_attrs(struct hid_device *hdev);
870
871#define CP2112_CONFIG_ATTR(name, store, format, ...) \
872static ssize_t name##_store(struct device *kdev, \
873 struct device_attribute *attr, const char *buf, \
874 size_t count) \
875{ \
876 struct hid_device *hdev = to_hid_device(kdev); \
877 struct cp2112_usb_config_report cfg; \
878 int ret = cp2112_get_usb_config(hdev, &cfg); \
879 if (ret) \
880 return ret; \
881 store; \
882 ret = cp2112_set_usb_config(hdev, &cfg); \
883 if (ret) \
884 return ret; \
885 chmod_sysfs_attrs(hdev); \
886 return count; \
887} \
888static ssize_t name##_show(struct device *kdev, \
889 struct device_attribute *attr, char *buf) \
890{ \
891 struct hid_device *hdev = to_hid_device(kdev); \
892 struct cp2112_usb_config_report cfg; \
893 int ret = cp2112_get_usb_config(hdev, &cfg); \
894 if (ret) \
895 return ret; \
896 return sysfs_emit(buf, format, ##__VA_ARGS__); \
897} \
898static DEVICE_ATTR_RW(name);
899
900CP2112_CONFIG_ATTR(vendor_id, ({
901 u16 vid;
902
903 if (sscanf(buf, "%hi", &vid) != 1)
904 return -EINVAL;
905
906 cfg.vid = cpu_to_le16(vid);
907 cfg.mask = 0x01;
908}), "0x%04x\n", le16_to_cpu(cfg.vid));
909
910CP2112_CONFIG_ATTR(product_id, ({
911 u16 pid;
912
913 if (sscanf(buf, "%hi", &pid) != 1)
914 return -EINVAL;
915
916 cfg.pid = cpu_to_le16(pid);
917 cfg.mask = 0x02;
918}), "0x%04x\n", le16_to_cpu(cfg.pid));
919
920CP2112_CONFIG_ATTR(max_power, ({
921 int mA;
922
923 if (sscanf(buf, "%i", &mA) != 1)
924 return -EINVAL;
925
926 cfg.max_power = (mA + 1) / 2;
927 cfg.mask = 0x04;
928}), "%u mA\n", cfg.max_power * 2);
929
930CP2112_CONFIG_ATTR(power_mode, ({
931 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
932 return -EINVAL;
933
934 cfg.mask = 0x08;
935}), "%u\n", cfg.power_mode);
936
937CP2112_CONFIG_ATTR(release_version, ({
938 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
939 != 2)
940 return -EINVAL;
941
942 cfg.mask = 0x10;
943}), "%u.%u\n", cfg.release_major, cfg.release_minor);
944
945#undef CP2112_CONFIG_ATTR
946
947static ssize_t pstr_store(struct device *kdev, struct device_attribute *kattr,
948 const char *buf, size_t count, int number)
949{
950 struct hid_device *hdev = to_hid_device(kdev);
951 struct cp2112_string_report report;
952 int ret;
953
954 memset(&report, 0, sizeof(report));
955
956 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
957 report.string, ARRAY_SIZE(report.string));
958 report.report = number;
959 report.length = ret * sizeof(report.string[0]) + 2;
960 report.type = USB_DT_STRING;
961
962 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
963 HID_FEATURE_REPORT);
964 if (ret != report.length + 1) {
965 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
966 ret);
967 if (ret < 0)
968 return ret;
969 return -EIO;
970 }
971
972 chmod_sysfs_attrs(hdev);
973 return count;
974}
975
976static ssize_t pstr_show(struct device *kdev, struct device_attribute *kattr,
977 char *buf, int number)
978{
979 struct hid_device *hdev = to_hid_device(kdev);
980 struct cp2112_string_report report;
981 u8 length;
982 int ret;
983
984 ret = cp2112_hid_get(hdev, number, (u8 *)&report.contents,
985 sizeof(report.contents), HID_FEATURE_REPORT);
986 if (ret < 3) {
987 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
988 ret);
989 if (ret < 0)
990 return ret;
991 return -EIO;
992 }
993
994 if (report.length < 2) {
995 hid_err(hdev, "invalid %s string length: %d\n",
996 kattr->attr.name, report.length);
997 return -EIO;
998 }
999
1000 length = report.length > ret - 1 ? ret - 1 : report.length;
1001 length = (length - 2) / sizeof(report.string[0]);
1002 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1003 PAGE_SIZE - 1);
1004 buf[ret++] = '\n';
1005 return ret;
1006}
1007
1008#define CP2112_PSTR_ATTR(name, _report) \
1009static ssize_t name##_store(struct device *kdev, struct device_attribute *kattr, \
1010 const char *buf, size_t count) \
1011{ \
1012 return pstr_store(kdev, kattr, buf, count, _report); \
1013} \
1014static ssize_t name##_show(struct device *kdev, struct device_attribute *kattr, char *buf) \
1015{ \
1016 return pstr_show(kdev, kattr, buf, _report); \
1017} \
1018static DEVICE_ATTR_RW(name);
1019
1020CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
1021CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
1022CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
1023
1024#undef CP2112_PSTR_ATTR
1025
1026static const struct attribute_group cp2112_attr_group = {
1027 .attrs = (struct attribute *[]){
1028 &dev_attr_vendor_id.attr,
1029 &dev_attr_product_id.attr,
1030 &dev_attr_max_power.attr,
1031 &dev_attr_power_mode.attr,
1032 &dev_attr_release_version.attr,
1033 &dev_attr_manufacturer.attr,
1034 &dev_attr_product.attr,
1035 &dev_attr_serial.attr,
1036 NULL
1037 }
1038};
1039
1040/* Chmoding our sysfs attributes is simply a way to expose which fields in the
1041 * PROM have already been programmed. We do not depend on this preventing
1042 * writing to these attributes since the CP2112 will simply ignore writes to
1043 * already-programmed fields. This is why there is no sense in fixing this
1044 * racy behaviour.
1045 */
1046static void chmod_sysfs_attrs(struct hid_device *hdev)
1047{
1048 struct attribute **attr;
1049 u8 buf[2];
1050 int ret;
1051
1052 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1053 HID_FEATURE_REPORT);
1054 if (ret != sizeof(buf)) {
1055 hid_err(hdev, "error reading lock byte: %d\n", ret);
1056 return;
1057 }
1058
1059 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1060 umode_t mode = (buf[1] & 1) ? 0644 : 0444;
1061 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1062 if (ret < 0)
1063 hid_err(hdev, "error chmoding sysfs file %s\n",
1064 (*attr)->name);
1065 buf[1] >>= 1;
1066 }
1067}
1068
1069static void cp2112_gpio_irq_ack(struct irq_data *d)
1070{
1071}
1072
1073static void cp2112_gpio_irq_mask(struct irq_data *d)
1074{
1075 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1076 struct cp2112_device *dev = gpiochip_get_data(gc);
1077 irq_hw_number_t hwirq = irqd_to_hwirq(d);
1078
1079 __clear_bit(hwirq, &dev->irq_mask);
1080 gpiochip_disable_irq(gc, hwirq);
1081}
1082
1083static void cp2112_gpio_irq_unmask(struct irq_data *d)
1084{
1085 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1086 struct cp2112_device *dev = gpiochip_get_data(gc);
1087 irq_hw_number_t hwirq = irqd_to_hwirq(d);
1088
1089 gpiochip_enable_irq(gc, hwirq);
1090 __set_bit(hwirq, &dev->irq_mask);
1091}
1092
1093static void cp2112_gpio_poll_callback(struct work_struct *work)
1094{
1095 struct cp2112_device *dev = container_of(work, struct cp2112_device,
1096 gpio_poll_worker.work);
1097 struct irq_data *d;
1098 u8 gpio_mask;
1099 u32 irq_type;
1100 int irq, virq, ret;
1101
1102 ret = cp2112_gpio_get_all(&dev->gc);
1103 if (ret == -ENODEV) /* the hardware has been disconnected */
1104 return;
1105 if (ret < 0)
1106 goto exit;
1107
1108 gpio_mask = ret;
1109 for_each_set_bit(virq, &dev->irq_mask, CP2112_GPIO_MAX_GPIO) {
1110 irq = irq_find_mapping(dev->gc.irq.domain, virq);
1111 if (!irq)
1112 continue;
1113
1114 d = irq_get_irq_data(irq);
1115 if (!d)
1116 continue;
1117
1118 irq_type = irqd_get_trigger_type(d);
1119
1120 if (gpio_mask & BIT(virq)) {
1121 /* Level High */
1122
1123 if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1124 handle_nested_irq(irq);
1125
1126 if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1127 !(dev->gpio_prev_state & BIT(virq)))
1128 handle_nested_irq(irq);
1129 } else {
1130 /* Level Low */
1131
1132 if (irq_type & IRQ_TYPE_LEVEL_LOW)
1133 handle_nested_irq(irq);
1134
1135 if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1136 (dev->gpio_prev_state & BIT(virq)))
1137 handle_nested_irq(irq);
1138 }
1139 }
1140
1141 dev->gpio_prev_state = gpio_mask;
1142
1143exit:
1144 if (dev->gpio_poll)
1145 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1146}
1147
1148
1149static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1150{
1151 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1152 struct cp2112_device *dev = gpiochip_get_data(gc);
1153
1154 if (!dev->gpio_poll) {
1155 dev->gpio_poll = true;
1156 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1157 }
1158
1159 cp2112_gpio_irq_unmask(d);
1160 return 0;
1161}
1162
1163static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1164{
1165 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1166 struct cp2112_device *dev = gpiochip_get_data(gc);
1167
1168 cp2112_gpio_irq_mask(d);
1169
1170 if (!dev->irq_mask) {
1171 dev->gpio_poll = false;
1172 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1173 }
1174}
1175
1176static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1177{
1178 return 0;
1179}
1180
1181static const struct irq_chip cp2112_gpio_irqchip = {
1182 .name = "cp2112-gpio",
1183 .irq_startup = cp2112_gpio_irq_startup,
1184 .irq_shutdown = cp2112_gpio_irq_shutdown,
1185 .irq_ack = cp2112_gpio_irq_ack,
1186 .irq_mask = cp2112_gpio_irq_mask,
1187 .irq_unmask = cp2112_gpio_irq_unmask,
1188 .irq_set_type = cp2112_gpio_irq_type,
1189 .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
1190 GPIOCHIP_IRQ_RESOURCE_HELPERS,
1191};
1192
1193static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1194{
1195 struct cp2112_device *dev;
1196 u8 buf[3];
1197 struct cp2112_smbus_config_report config;
1198 struct gpio_irq_chip *girq;
1199 int ret;
1200
1201 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1202 if (!dev)
1203 return -ENOMEM;
1204
1205 dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1206 GFP_KERNEL);
1207 if (!dev->in_out_buffer)
1208 return -ENOMEM;
1209
1210 mutex_init(&dev->lock);
1211
1212 ret = hid_parse(hdev);
1213 if (ret) {
1214 hid_err(hdev, "parse failed\n");
1215 return ret;
1216 }
1217
1218 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1219 if (ret) {
1220 hid_err(hdev, "hw start failed\n");
1221 return ret;
1222 }
1223
1224 ret = hid_hw_open(hdev);
1225 if (ret) {
1226 hid_err(hdev, "hw open failed\n");
1227 goto err_hid_stop;
1228 }
1229
1230 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1231 if (ret < 0) {
1232 hid_err(hdev, "power management error: %d\n", ret);
1233 goto err_hid_close;
1234 }
1235
1236 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1237 HID_FEATURE_REPORT);
1238 if (ret != sizeof(buf)) {
1239 hid_err(hdev, "error requesting version\n");
1240 if (ret >= 0)
1241 ret = -EIO;
1242 goto err_power_normal;
1243 }
1244
1245 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1246 buf[1], buf[2]);
1247
1248 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1249 sizeof(config), HID_FEATURE_REPORT);
1250 if (ret != sizeof(config)) {
1251 hid_err(hdev, "error requesting SMBus config\n");
1252 if (ret >= 0)
1253 ret = -EIO;
1254 goto err_power_normal;
1255 }
1256
1257 config.retry_time = cpu_to_be16(1);
1258
1259 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1260 HID_FEATURE_REPORT);
1261 if (ret != sizeof(config)) {
1262 hid_err(hdev, "error setting SMBus config\n");
1263 if (ret >= 0)
1264 ret = -EIO;
1265 goto err_power_normal;
1266 }
1267
1268 hid_set_drvdata(hdev, (void *)dev);
1269 dev->hdev = hdev;
1270 dev->adap.owner = THIS_MODULE;
1271 dev->adap.class = I2C_CLASS_HWMON;
1272 dev->adap.algo = &smbus_algorithm;
1273 dev->adap.algo_data = dev;
1274 dev->adap.dev.parent = &hdev->dev;
1275 snprintf(dev->adap.name, sizeof(dev->adap.name),
1276 "CP2112 SMBus Bridge on hidraw%d",
1277 ((struct hidraw *)hdev->hidraw)->minor);
1278 dev->hwversion = buf[2];
1279 init_waitqueue_head(&dev->wait);
1280
1281 hid_device_io_start(hdev);
1282 ret = i2c_add_adapter(&dev->adap);
1283 hid_device_io_stop(hdev);
1284
1285 if (ret) {
1286 hid_err(hdev, "error registering i2c adapter\n");
1287 goto err_power_normal;
1288 }
1289
1290 hid_dbg(hdev, "adapter registered\n");
1291
1292 dev->gc.label = "cp2112_gpio";
1293 dev->gc.direction_input = cp2112_gpio_direction_input;
1294 dev->gc.direction_output = cp2112_gpio_direction_output;
1295 dev->gc.set = cp2112_gpio_set;
1296 dev->gc.get = cp2112_gpio_get;
1297 dev->gc.base = -1;
1298 dev->gc.ngpio = CP2112_GPIO_MAX_GPIO;
1299 dev->gc.can_sleep = 1;
1300 dev->gc.parent = &hdev->dev;
1301
1302 girq = &dev->gc.irq;
1303 gpio_irq_chip_set_chip(girq, &cp2112_gpio_irqchip);
1304 /* The event comes from the outside so no parent handler */
1305 girq->parent_handler = NULL;
1306 girq->num_parents = 0;
1307 girq->parents = NULL;
1308 girq->default_type = IRQ_TYPE_NONE;
1309 girq->handler = handle_simple_irq;
1310 girq->threaded = true;
1311
1312 INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1313
1314 ret = gpiochip_add_data(&dev->gc, dev);
1315 if (ret < 0) {
1316 hid_err(hdev, "error registering gpio chip\n");
1317 goto err_free_i2c;
1318 }
1319
1320 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1321 if (ret < 0) {
1322 hid_err(hdev, "error creating sysfs attrs\n");
1323 goto err_gpiochip_remove;
1324 }
1325
1326 chmod_sysfs_attrs(hdev);
1327 hid_hw_power(hdev, PM_HINT_NORMAL);
1328
1329 return ret;
1330
1331err_gpiochip_remove:
1332 gpiochip_remove(&dev->gc);
1333err_free_i2c:
1334 i2c_del_adapter(&dev->adap);
1335err_power_normal:
1336 hid_hw_power(hdev, PM_HINT_NORMAL);
1337err_hid_close:
1338 hid_hw_close(hdev);
1339err_hid_stop:
1340 hid_hw_stop(hdev);
1341 return ret;
1342}
1343
1344static void cp2112_remove(struct hid_device *hdev)
1345{
1346 struct cp2112_device *dev = hid_get_drvdata(hdev);
1347
1348 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1349 i2c_del_adapter(&dev->adap);
1350
1351 if (dev->gpio_poll) {
1352 dev->gpio_poll = false;
1353 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1354 }
1355
1356 gpiochip_remove(&dev->gc);
1357 /* i2c_del_adapter has finished removing all i2c devices from our
1358 * adapter. Well behaved devices should no longer call our cp2112_xfer
1359 * and should have waited for any pending calls to finish. It has also
1360 * waited for device_unregister(&adap->dev) to complete. Therefore we
1361 * can safely free our struct cp2112_device.
1362 */
1363 hid_hw_close(hdev);
1364 hid_hw_stop(hdev);
1365}
1366
1367static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1368 u8 *data, int size)
1369{
1370 struct cp2112_device *dev = hid_get_drvdata(hdev);
1371 struct cp2112_xfer_status_report *xfer = (void *)data;
1372
1373 switch (data[0]) {
1374 case CP2112_TRANSFER_STATUS_RESPONSE:
1375 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1376 xfer->status0, xfer->status1,
1377 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1378
1379 switch (xfer->status0) {
1380 case STATUS0_IDLE:
1381 dev->xfer_status = -EAGAIN;
1382 break;
1383 case STATUS0_BUSY:
1384 dev->xfer_status = -EBUSY;
1385 break;
1386 case STATUS0_COMPLETE:
1387 dev->xfer_status = be16_to_cpu(xfer->length);
1388 break;
1389 case STATUS0_ERROR:
1390 switch (xfer->status1) {
1391 case STATUS1_TIMEOUT_NACK:
1392 case STATUS1_TIMEOUT_BUS:
1393 dev->xfer_status = -ETIMEDOUT;
1394 break;
1395 default:
1396 dev->xfer_status = -EIO;
1397 break;
1398 }
1399 break;
1400 default:
1401 dev->xfer_status = -EINVAL;
1402 break;
1403 }
1404
1405 atomic_set(&dev->xfer_avail, 1);
1406 break;
1407 case CP2112_DATA_READ_RESPONSE:
1408 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1409
1410 dev->read_length = data[2];
1411 if (dev->read_length > sizeof(dev->read_data))
1412 dev->read_length = sizeof(dev->read_data);
1413
1414 memcpy(dev->read_data, &data[3], dev->read_length);
1415 atomic_set(&dev->read_avail, 1);
1416 break;
1417 default:
1418 hid_err(hdev, "unknown report\n");
1419
1420 return 0;
1421 }
1422
1423 wake_up_interruptible(&dev->wait);
1424 return 1;
1425}
1426
1427static struct hid_driver cp2112_driver = {
1428 .name = "cp2112",
1429 .id_table = cp2112_devices,
1430 .probe = cp2112_probe,
1431 .remove = cp2112_remove,
1432 .raw_event = cp2112_raw_event,
1433};
1434
1435module_hid_driver(cp2112_driver);
1436MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1437MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1438MODULE_LICENSE("GPL");
1439
1/*
2 * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
3 * Copyright (c) 2013,2014 Uplogix, Inc.
4 * David Barksdale <dbarksdale@uplogix.com>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 */
15
16/*
17 * The Silicon Labs CP2112 chip is a USB HID device which provides an
18 * SMBus controller for talking to slave devices and 8 GPIO pins. The
19 * host communicates with the CP2112 via raw HID reports.
20 *
21 * Data Sheet:
22 * http://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
23 * Programming Interface Specification:
24 * http://www.silabs.com/Support%20Documents/TechnicalDocs/AN495.pdf
25 */
26
27#include <linux/gpio.h>
28#include <linux/hid.h>
29#include <linux/i2c.h>
30#include <linux/module.h>
31#include <linux/nls.h>
32#include <linux/usb/ch9.h>
33#include "hid-ids.h"
34
35enum {
36 CP2112_GPIO_CONFIG = 0x02,
37 CP2112_GPIO_GET = 0x03,
38 CP2112_GPIO_SET = 0x04,
39 CP2112_GET_VERSION_INFO = 0x05,
40 CP2112_SMBUS_CONFIG = 0x06,
41 CP2112_DATA_READ_REQUEST = 0x10,
42 CP2112_DATA_WRITE_READ_REQUEST = 0x11,
43 CP2112_DATA_READ_FORCE_SEND = 0x12,
44 CP2112_DATA_READ_RESPONSE = 0x13,
45 CP2112_DATA_WRITE_REQUEST = 0x14,
46 CP2112_TRANSFER_STATUS_REQUEST = 0x15,
47 CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
48 CP2112_CANCEL_TRANSFER = 0x17,
49 CP2112_LOCK_BYTE = 0x20,
50 CP2112_USB_CONFIG = 0x21,
51 CP2112_MANUFACTURER_STRING = 0x22,
52 CP2112_PRODUCT_STRING = 0x23,
53 CP2112_SERIAL_STRING = 0x24,
54};
55
56enum {
57 STATUS0_IDLE = 0x00,
58 STATUS0_BUSY = 0x01,
59 STATUS0_COMPLETE = 0x02,
60 STATUS0_ERROR = 0x03,
61};
62
63enum {
64 STATUS1_TIMEOUT_NACK = 0x00,
65 STATUS1_TIMEOUT_BUS = 0x01,
66 STATUS1_ARBITRATION_LOST = 0x02,
67 STATUS1_READ_INCOMPLETE = 0x03,
68 STATUS1_WRITE_INCOMPLETE = 0x04,
69 STATUS1_SUCCESS = 0x05,
70};
71
72struct cp2112_smbus_config_report {
73 u8 report; /* CP2112_SMBUS_CONFIG */
74 __be32 clock_speed; /* Hz */
75 u8 device_address; /* Stored in the upper 7 bits */
76 u8 auto_send_read; /* 1 = enabled, 0 = disabled */
77 __be16 write_timeout; /* ms, 0 = no timeout */
78 __be16 read_timeout; /* ms, 0 = no timeout */
79 u8 scl_low_timeout; /* 1 = enabled, 0 = disabled */
80 __be16 retry_time; /* # of retries, 0 = no limit */
81} __packed;
82
83struct cp2112_usb_config_report {
84 u8 report; /* CP2112_USB_CONFIG */
85 __le16 vid; /* Vendor ID */
86 __le16 pid; /* Product ID */
87 u8 max_power; /* Power requested in 2mA units */
88 u8 power_mode; /* 0x00 = bus powered
89 0x01 = self powered & regulator off
90 0x02 = self powered & regulator on */
91 u8 release_major;
92 u8 release_minor;
93 u8 mask; /* What fields to program */
94} __packed;
95
96struct cp2112_read_req_report {
97 u8 report; /* CP2112_DATA_READ_REQUEST */
98 u8 slave_address;
99 __be16 length;
100} __packed;
101
102struct cp2112_write_read_req_report {
103 u8 report; /* CP2112_DATA_WRITE_READ_REQUEST */
104 u8 slave_address;
105 __be16 length;
106 u8 target_address_length;
107 u8 target_address[16];
108} __packed;
109
110struct cp2112_write_req_report {
111 u8 report; /* CP2112_DATA_WRITE_REQUEST */
112 u8 slave_address;
113 u8 length;
114 u8 data[61];
115} __packed;
116
117struct cp2112_force_read_report {
118 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
119 __be16 length;
120} __packed;
121
122struct cp2112_xfer_status_report {
123 u8 report; /* CP2112_TRANSFER_STATUS_RESPONSE */
124 u8 status0; /* STATUS0_* */
125 u8 status1; /* STATUS1_* */
126 __be16 retries;
127 __be16 length;
128} __packed;
129
130struct cp2112_string_report {
131 u8 dummy; /* force .string to be aligned */
132 u8 report; /* CP2112_*_STRING */
133 u8 length; /* length in bytes of everyting after .report */
134 u8 type; /* USB_DT_STRING */
135 wchar_t string[30]; /* UTF16_LITTLE_ENDIAN string */
136} __packed;
137
138/* Number of times to request transfer status before giving up waiting for a
139 transfer to complete. This may need to be changed if SMBUS clock, retries,
140 or read/write/scl_low timeout settings are changed. */
141static const int XFER_STATUS_RETRIES = 10;
142
143/* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
144 CP2112_TRANSFER_STATUS_RESPONSE. */
145static const int RESPONSE_TIMEOUT = 50;
146
147static const struct hid_device_id cp2112_devices[] = {
148 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
149 { }
150};
151MODULE_DEVICE_TABLE(hid, cp2112_devices);
152
153struct cp2112_device {
154 struct i2c_adapter adap;
155 struct hid_device *hdev;
156 wait_queue_head_t wait;
157 u8 read_data[61];
158 u8 read_length;
159 int xfer_status;
160 atomic_t read_avail;
161 atomic_t xfer_avail;
162 struct gpio_chip gc;
163};
164
165static int gpio_push_pull = 0xFF;
166module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
167MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
168
169static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
170{
171 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
172 gc);
173 struct hid_device *hdev = dev->hdev;
174 u8 buf[5];
175 int ret;
176
177 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
178 sizeof(buf), HID_FEATURE_REPORT,
179 HID_REQ_GET_REPORT);
180 if (ret != sizeof(buf)) {
181 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
182 return ret;
183 }
184
185 buf[1] &= ~(1 << offset);
186 buf[2] = gpio_push_pull;
187
188 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf),
189 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
190 if (ret < 0) {
191 hid_err(hdev, "error setting GPIO config: %d\n", ret);
192 return ret;
193 }
194
195 return 0;
196}
197
198static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
199{
200 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
201 gc);
202 struct hid_device *hdev = dev->hdev;
203 u8 buf[3];
204 int ret;
205
206 buf[0] = CP2112_GPIO_SET;
207 buf[1] = value ? 0xff : 0;
208 buf[2] = 1 << offset;
209
210 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf, sizeof(buf),
211 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
212 if (ret < 0)
213 hid_err(hdev, "error setting GPIO values: %d\n", ret);
214}
215
216static int cp2112_gpio_get(struct gpio_chip *chip, unsigned offset)
217{
218 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
219 gc);
220 struct hid_device *hdev = dev->hdev;
221 u8 buf[2];
222 int ret;
223
224 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf, sizeof(buf),
225 HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
226 if (ret != sizeof(buf)) {
227 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
228 return ret;
229 }
230
231 return (buf[1] >> offset) & 1;
232}
233
234static int cp2112_gpio_direction_output(struct gpio_chip *chip,
235 unsigned offset, int value)
236{
237 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
238 gc);
239 struct hid_device *hdev = dev->hdev;
240 u8 buf[5];
241 int ret;
242
243 cp2112_gpio_set(chip, offset, value);
244
245 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
246 sizeof(buf), HID_FEATURE_REPORT,
247 HID_REQ_GET_REPORT);
248 if (ret != sizeof(buf)) {
249 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
250 return ret;
251 }
252
253 buf[1] |= 1 << offset;
254 buf[2] = gpio_push_pull;
255
256 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf),
257 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
258 if (ret < 0) {
259 hid_err(hdev, "error setting GPIO config: %d\n", ret);
260 return ret;
261 }
262
263 return 0;
264}
265
266static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
267 u8 *data, size_t count, unsigned char report_type)
268{
269 u8 *buf;
270 int ret;
271
272 buf = kmalloc(count, GFP_KERNEL);
273 if (!buf)
274 return -ENOMEM;
275
276 ret = hid_hw_raw_request(hdev, report_number, buf, count,
277 report_type, HID_REQ_GET_REPORT);
278 memcpy(data, buf, count);
279 kfree(buf);
280 return ret;
281}
282
283static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
284 unsigned char report_type)
285{
286 u8 *buf;
287 int ret;
288
289 buf = kmemdup(data, count, GFP_KERNEL);
290 if (!buf)
291 return -ENOMEM;
292
293 if (report_type == HID_OUTPUT_REPORT)
294 ret = hid_hw_output_report(hdev, buf, count);
295 else
296 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
297 HID_REQ_SET_REPORT);
298
299 kfree(buf);
300 return ret;
301}
302
303static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
304{
305 int ret = 0;
306
307 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
308 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
309 * come in cp2112_raw_event or timeout. There will only be one of these
310 * in flight at any one time. The timeout is extremely large and is a
311 * last resort if the CP2112 has died. If we do timeout we don't expect
312 * to receive the response which would cause data races, it's not like
313 * we can do anything about it anyway.
314 */
315 ret = wait_event_interruptible_timeout(dev->wait,
316 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
317 if (-ERESTARTSYS == ret)
318 return ret;
319 if (!ret)
320 return -ETIMEDOUT;
321
322 atomic_set(avail, 0);
323 return 0;
324}
325
326static int cp2112_xfer_status(struct cp2112_device *dev)
327{
328 struct hid_device *hdev = dev->hdev;
329 u8 buf[2];
330 int ret;
331
332 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
333 buf[1] = 0x01;
334 atomic_set(&dev->xfer_avail, 0);
335
336 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
337 if (ret < 0) {
338 hid_warn(hdev, "Error requesting status: %d\n", ret);
339 return ret;
340 }
341
342 ret = cp2112_wait(dev, &dev->xfer_avail);
343 if (ret)
344 return ret;
345
346 return dev->xfer_status;
347}
348
349static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
350{
351 struct hid_device *hdev = dev->hdev;
352 struct cp2112_force_read_report report;
353 int ret;
354
355 report.report = CP2112_DATA_READ_FORCE_SEND;
356 report.length = cpu_to_be16(size);
357
358 atomic_set(&dev->read_avail, 0);
359
360 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
361 HID_OUTPUT_REPORT);
362 if (ret < 0) {
363 hid_warn(hdev, "Error requesting data: %d\n", ret);
364 return ret;
365 }
366
367 ret = cp2112_wait(dev, &dev->read_avail);
368 if (ret)
369 return ret;
370
371 hid_dbg(hdev, "read %d of %zd bytes requested\n",
372 dev->read_length, size);
373
374 if (size > dev->read_length)
375 size = dev->read_length;
376
377 memcpy(data, dev->read_data, size);
378 return dev->read_length;
379}
380
381static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
382{
383 struct cp2112_read_req_report *report = buf;
384
385 if (length < 1 || length > 512)
386 return -EINVAL;
387
388 report->report = CP2112_DATA_READ_REQUEST;
389 report->slave_address = slave_address << 1;
390 report->length = cpu_to_be16(length);
391 return sizeof(*report);
392}
393
394static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
395 u8 command, u8 *data, u8 data_length)
396{
397 struct cp2112_write_read_req_report *report = buf;
398
399 if (length < 1 || length > 512
400 || data_length > sizeof(report->target_address) - 1)
401 return -EINVAL;
402
403 report->report = CP2112_DATA_WRITE_READ_REQUEST;
404 report->slave_address = slave_address << 1;
405 report->length = cpu_to_be16(length);
406 report->target_address_length = data_length + 1;
407 report->target_address[0] = command;
408 memcpy(&report->target_address[1], data, data_length);
409 return data_length + 6;
410}
411
412static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
413 u8 data_length)
414{
415 struct cp2112_write_req_report *report = buf;
416
417 if (data_length > sizeof(report->data) - 1)
418 return -EINVAL;
419
420 report->report = CP2112_DATA_WRITE_REQUEST;
421 report->slave_address = slave_address << 1;
422 report->length = data_length + 1;
423 report->data[0] = command;
424 memcpy(&report->data[1], data, data_length);
425 return data_length + 4;
426}
427
428static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
429 unsigned short flags, char read_write, u8 command,
430 int size, union i2c_smbus_data *data)
431{
432 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
433 struct hid_device *hdev = dev->hdev;
434 u8 buf[64];
435 __be16 word;
436 ssize_t count;
437 size_t read_length = 0;
438 unsigned int retries;
439 int ret;
440
441 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
442 read_write == I2C_SMBUS_WRITE ? "write" : "read",
443 addr, flags, command, size);
444
445 switch (size) {
446 case I2C_SMBUS_BYTE:
447 read_length = 1;
448
449 if (I2C_SMBUS_READ == read_write)
450 count = cp2112_read_req(buf, addr, read_length);
451 else
452 count = cp2112_write_req(buf, addr, data->byte, NULL,
453 0);
454 break;
455 case I2C_SMBUS_BYTE_DATA:
456 read_length = 1;
457
458 if (I2C_SMBUS_READ == read_write)
459 count = cp2112_write_read_req(buf, addr, read_length,
460 command, NULL, 0);
461 else
462 count = cp2112_write_req(buf, addr, command,
463 &data->byte, 1);
464 break;
465 case I2C_SMBUS_WORD_DATA:
466 read_length = 2;
467 word = cpu_to_be16(data->word);
468
469 if (I2C_SMBUS_READ == read_write)
470 count = cp2112_write_read_req(buf, addr, read_length,
471 command, NULL, 0);
472 else
473 count = cp2112_write_req(buf, addr, command,
474 (u8 *)&word, 2);
475 break;
476 case I2C_SMBUS_PROC_CALL:
477 size = I2C_SMBUS_WORD_DATA;
478 read_write = I2C_SMBUS_READ;
479 read_length = 2;
480 word = cpu_to_be16(data->word);
481
482 count = cp2112_write_read_req(buf, addr, read_length, command,
483 (u8 *)&word, 2);
484 break;
485 case I2C_SMBUS_I2C_BLOCK_DATA:
486 size = I2C_SMBUS_BLOCK_DATA;
487 /* fallthrough */
488 case I2C_SMBUS_BLOCK_DATA:
489 if (I2C_SMBUS_READ == read_write) {
490 count = cp2112_write_read_req(buf, addr,
491 I2C_SMBUS_BLOCK_MAX,
492 command, NULL, 0);
493 } else {
494 count = cp2112_write_req(buf, addr, command,
495 data->block,
496 data->block[0] + 1);
497 }
498 break;
499 case I2C_SMBUS_BLOCK_PROC_CALL:
500 size = I2C_SMBUS_BLOCK_DATA;
501 read_write = I2C_SMBUS_READ;
502
503 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
504 command, data->block,
505 data->block[0] + 1);
506 break;
507 default:
508 hid_warn(hdev, "Unsupported transaction %d\n", size);
509 return -EOPNOTSUPP;
510 }
511
512 if (count < 0)
513 return count;
514
515 ret = hid_hw_power(hdev, PM_HINT_FULLON);
516 if (ret < 0) {
517 hid_err(hdev, "power management error: %d\n", ret);
518 return ret;
519 }
520
521 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
522 if (ret < 0) {
523 hid_warn(hdev, "Error starting transaction: %d\n", ret);
524 goto power_normal;
525 }
526
527 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
528 ret = cp2112_xfer_status(dev);
529 if (-EBUSY == ret)
530 continue;
531 if (ret < 0)
532 goto power_normal;
533 break;
534 }
535
536 if (XFER_STATUS_RETRIES <= retries) {
537 hid_warn(hdev, "Transfer timed out, cancelling.\n");
538 buf[0] = CP2112_CANCEL_TRANSFER;
539 buf[1] = 0x01;
540
541 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
542 if (ret < 0)
543 hid_warn(hdev, "Error cancelling transaction: %d\n",
544 ret);
545
546 ret = -ETIMEDOUT;
547 goto power_normal;
548 }
549
550 if (I2C_SMBUS_WRITE == read_write) {
551 ret = 0;
552 goto power_normal;
553 }
554
555 if (I2C_SMBUS_BLOCK_DATA == size)
556 read_length = ret;
557
558 ret = cp2112_read(dev, buf, read_length);
559 if (ret < 0)
560 goto power_normal;
561 if (ret != read_length) {
562 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
563 ret = -EIO;
564 goto power_normal;
565 }
566
567 switch (size) {
568 case I2C_SMBUS_BYTE:
569 case I2C_SMBUS_BYTE_DATA:
570 data->byte = buf[0];
571 break;
572 case I2C_SMBUS_WORD_DATA:
573 data->word = be16_to_cpup((__be16 *)buf);
574 break;
575 case I2C_SMBUS_BLOCK_DATA:
576 if (read_length > I2C_SMBUS_BLOCK_MAX) {
577 ret = -EPROTO;
578 goto power_normal;
579 }
580
581 memcpy(data->block, buf, read_length);
582 break;
583 }
584
585 ret = 0;
586power_normal:
587 hid_hw_power(hdev, PM_HINT_NORMAL);
588 hid_dbg(hdev, "transfer finished: %d\n", ret);
589 return ret;
590}
591
592static u32 cp2112_functionality(struct i2c_adapter *adap)
593{
594 return I2C_FUNC_SMBUS_BYTE |
595 I2C_FUNC_SMBUS_BYTE_DATA |
596 I2C_FUNC_SMBUS_WORD_DATA |
597 I2C_FUNC_SMBUS_BLOCK_DATA |
598 I2C_FUNC_SMBUS_I2C_BLOCK |
599 I2C_FUNC_SMBUS_PROC_CALL |
600 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
601}
602
603static const struct i2c_algorithm smbus_algorithm = {
604 .smbus_xfer = cp2112_xfer,
605 .functionality = cp2112_functionality,
606};
607
608static int cp2112_get_usb_config(struct hid_device *hdev,
609 struct cp2112_usb_config_report *cfg)
610{
611 int ret;
612
613 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
614 HID_FEATURE_REPORT);
615 if (ret != sizeof(*cfg)) {
616 hid_err(hdev, "error reading usb config: %d\n", ret);
617 if (ret < 0)
618 return ret;
619 return -EIO;
620 }
621
622 return 0;
623}
624
625static int cp2112_set_usb_config(struct hid_device *hdev,
626 struct cp2112_usb_config_report *cfg)
627{
628 int ret;
629
630 BUG_ON(cfg->report != CP2112_USB_CONFIG);
631
632 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
633 HID_FEATURE_REPORT);
634 if (ret != sizeof(*cfg)) {
635 hid_err(hdev, "error writing usb config: %d\n", ret);
636 if (ret < 0)
637 return ret;
638 return -EIO;
639 }
640
641 return 0;
642}
643
644static void chmod_sysfs_attrs(struct hid_device *hdev);
645
646#define CP2112_CONFIG_ATTR(name, store, format, ...) \
647static ssize_t name##_store(struct device *kdev, \
648 struct device_attribute *attr, const char *buf, \
649 size_t count) \
650{ \
651 struct hid_device *hdev = container_of(kdev, struct hid_device, dev); \
652 struct cp2112_usb_config_report cfg; \
653 int ret = cp2112_get_usb_config(hdev, &cfg); \
654 if (ret) \
655 return ret; \
656 store; \
657 ret = cp2112_set_usb_config(hdev, &cfg); \
658 if (ret) \
659 return ret; \
660 chmod_sysfs_attrs(hdev); \
661 return count; \
662} \
663static ssize_t name##_show(struct device *kdev, \
664 struct device_attribute *attr, char *buf) \
665{ \
666 struct hid_device *hdev = container_of(kdev, struct hid_device, dev); \
667 struct cp2112_usb_config_report cfg; \
668 int ret = cp2112_get_usb_config(hdev, &cfg); \
669 if (ret) \
670 return ret; \
671 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
672} \
673static DEVICE_ATTR_RW(name);
674
675CP2112_CONFIG_ATTR(vendor_id, ({
676 u16 vid;
677
678 if (sscanf(buf, "%hi", &vid) != 1)
679 return -EINVAL;
680
681 cfg.vid = cpu_to_le16(vid);
682 cfg.mask = 0x01;
683}), "0x%04x\n", le16_to_cpu(cfg.vid));
684
685CP2112_CONFIG_ATTR(product_id, ({
686 u16 pid;
687
688 if (sscanf(buf, "%hi", &pid) != 1)
689 return -EINVAL;
690
691 cfg.pid = cpu_to_le16(pid);
692 cfg.mask = 0x02;
693}), "0x%04x\n", le16_to_cpu(cfg.pid));
694
695CP2112_CONFIG_ATTR(max_power, ({
696 int mA;
697
698 if (sscanf(buf, "%i", &mA) != 1)
699 return -EINVAL;
700
701 cfg.max_power = (mA + 1) / 2;
702 cfg.mask = 0x04;
703}), "%u mA\n", cfg.max_power * 2);
704
705CP2112_CONFIG_ATTR(power_mode, ({
706 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
707 return -EINVAL;
708
709 cfg.mask = 0x08;
710}), "%u\n", cfg.power_mode);
711
712CP2112_CONFIG_ATTR(release_version, ({
713 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
714 != 2)
715 return -EINVAL;
716
717 cfg.mask = 0x10;
718}), "%u.%u\n", cfg.release_major, cfg.release_minor);
719
720#undef CP2112_CONFIG_ATTR
721
722struct cp2112_pstring_attribute {
723 struct device_attribute attr;
724 unsigned char report;
725};
726
727static ssize_t pstr_store(struct device *kdev,
728 struct device_attribute *kattr, const char *buf,
729 size_t count)
730{
731 struct hid_device *hdev = container_of(kdev, struct hid_device, dev);
732 struct cp2112_pstring_attribute *attr =
733 container_of(kattr, struct cp2112_pstring_attribute, attr);
734 struct cp2112_string_report report;
735 int ret;
736
737 memset(&report, 0, sizeof(report));
738
739 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
740 report.string, ARRAY_SIZE(report.string));
741 report.report = attr->report;
742 report.length = ret * sizeof(report.string[0]) + 2;
743 report.type = USB_DT_STRING;
744
745 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
746 HID_FEATURE_REPORT);
747 if (ret != report.length + 1) {
748 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
749 ret);
750 if (ret < 0)
751 return ret;
752 return -EIO;
753 }
754
755 chmod_sysfs_attrs(hdev);
756 return count;
757}
758
759static ssize_t pstr_show(struct device *kdev,
760 struct device_attribute *kattr, char *buf)
761{
762 struct hid_device *hdev = container_of(kdev, struct hid_device, dev);
763 struct cp2112_pstring_attribute *attr =
764 container_of(kattr, struct cp2112_pstring_attribute, attr);
765 struct cp2112_string_report report;
766 u8 length;
767 int ret;
768
769 ret = cp2112_hid_get(hdev, attr->report, &report.report,
770 sizeof(report) - 1, HID_FEATURE_REPORT);
771 if (ret < 3) {
772 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
773 ret);
774 if (ret < 0)
775 return ret;
776 return -EIO;
777 }
778
779 if (report.length < 2) {
780 hid_err(hdev, "invalid %s string length: %d\n",
781 kattr->attr.name, report.length);
782 return -EIO;
783 }
784
785 length = report.length > ret - 1 ? ret - 1 : report.length;
786 length = (length - 2) / sizeof(report.string[0]);
787 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
788 PAGE_SIZE - 1);
789 buf[ret++] = '\n';
790 return ret;
791}
792
793#define CP2112_PSTR_ATTR(name, _report) \
794static struct cp2112_pstring_attribute dev_attr_##name = { \
795 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
796 .report = _report, \
797};
798
799CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
800CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
801CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
802
803#undef CP2112_PSTR_ATTR
804
805static const struct attribute_group cp2112_attr_group = {
806 .attrs = (struct attribute *[]){
807 &dev_attr_vendor_id.attr,
808 &dev_attr_product_id.attr,
809 &dev_attr_max_power.attr,
810 &dev_attr_power_mode.attr,
811 &dev_attr_release_version.attr,
812 &dev_attr_manufacturer.attr.attr,
813 &dev_attr_product.attr.attr,
814 &dev_attr_serial.attr.attr,
815 NULL
816 }
817};
818
819/* Chmoding our sysfs attributes is simply a way to expose which fields in the
820 * PROM have already been programmed. We do not depend on this preventing
821 * writing to these attributes since the CP2112 will simply ignore writes to
822 * already-programmed fields. This is why there is no sense in fixing this
823 * racy behaviour.
824 */
825static void chmod_sysfs_attrs(struct hid_device *hdev)
826{
827 struct attribute **attr;
828 u8 buf[2];
829 int ret;
830
831 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
832 HID_FEATURE_REPORT);
833 if (ret != sizeof(buf)) {
834 hid_err(hdev, "error reading lock byte: %d\n", ret);
835 return;
836 }
837
838 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
839 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
840 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
841 if (ret < 0)
842 hid_err(hdev, "error chmoding sysfs file %s\n",
843 (*attr)->name);
844 buf[1] >>= 1;
845 }
846}
847
848static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
849{
850 struct cp2112_device *dev;
851 u8 buf[3];
852 struct cp2112_smbus_config_report config;
853 int ret;
854
855 ret = hid_parse(hdev);
856 if (ret) {
857 hid_err(hdev, "parse failed\n");
858 return ret;
859 }
860
861 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
862 if (ret) {
863 hid_err(hdev, "hw start failed\n");
864 return ret;
865 }
866
867 ret = hid_hw_open(hdev);
868 if (ret) {
869 hid_err(hdev, "hw open failed\n");
870 goto err_hid_stop;
871 }
872
873 ret = hid_hw_power(hdev, PM_HINT_FULLON);
874 if (ret < 0) {
875 hid_err(hdev, "power management error: %d\n", ret);
876 goto err_hid_close;
877 }
878
879 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
880 HID_FEATURE_REPORT);
881 if (ret != sizeof(buf)) {
882 hid_err(hdev, "error requesting version\n");
883 if (ret >= 0)
884 ret = -EIO;
885 goto err_power_normal;
886 }
887
888 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
889 buf[1], buf[2]);
890
891 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
892 sizeof(config), HID_FEATURE_REPORT);
893 if (ret != sizeof(config)) {
894 hid_err(hdev, "error requesting SMBus config\n");
895 if (ret >= 0)
896 ret = -EIO;
897 goto err_power_normal;
898 }
899
900 config.retry_time = cpu_to_be16(1);
901
902 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
903 HID_FEATURE_REPORT);
904 if (ret != sizeof(config)) {
905 hid_err(hdev, "error setting SMBus config\n");
906 if (ret >= 0)
907 ret = -EIO;
908 goto err_power_normal;
909 }
910
911 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
912 if (!dev) {
913 ret = -ENOMEM;
914 goto err_power_normal;
915 }
916
917 hid_set_drvdata(hdev, (void *)dev);
918 dev->hdev = hdev;
919 dev->adap.owner = THIS_MODULE;
920 dev->adap.class = I2C_CLASS_HWMON;
921 dev->adap.algo = &smbus_algorithm;
922 dev->adap.algo_data = dev;
923 dev->adap.dev.parent = &hdev->dev;
924 snprintf(dev->adap.name, sizeof(dev->adap.name),
925 "CP2112 SMBus Bridge on hiddev%d", hdev->minor);
926 init_waitqueue_head(&dev->wait);
927
928 hid_device_io_start(hdev);
929 ret = i2c_add_adapter(&dev->adap);
930 hid_device_io_stop(hdev);
931
932 if (ret) {
933 hid_err(hdev, "error registering i2c adapter\n");
934 goto err_free_dev;
935 }
936
937 hid_dbg(hdev, "adapter registered\n");
938
939 dev->gc.label = "cp2112_gpio";
940 dev->gc.direction_input = cp2112_gpio_direction_input;
941 dev->gc.direction_output = cp2112_gpio_direction_output;
942 dev->gc.set = cp2112_gpio_set;
943 dev->gc.get = cp2112_gpio_get;
944 dev->gc.base = -1;
945 dev->gc.ngpio = 8;
946 dev->gc.can_sleep = 1;
947 dev->gc.dev = &hdev->dev;
948
949 ret = gpiochip_add(&dev->gc);
950 if (ret < 0) {
951 hid_err(hdev, "error registering gpio chip\n");
952 goto err_free_i2c;
953 }
954
955 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
956 if (ret < 0) {
957 hid_err(hdev, "error creating sysfs attrs\n");
958 goto err_gpiochip_remove;
959 }
960
961 chmod_sysfs_attrs(hdev);
962 hid_hw_power(hdev, PM_HINT_NORMAL);
963
964 return ret;
965
966err_gpiochip_remove:
967 if (gpiochip_remove(&dev->gc) < 0)
968 hid_err(hdev, "error removing gpio chip\n");
969err_free_i2c:
970 i2c_del_adapter(&dev->adap);
971err_free_dev:
972 kfree(dev);
973err_power_normal:
974 hid_hw_power(hdev, PM_HINT_NORMAL);
975err_hid_close:
976 hid_hw_close(hdev);
977err_hid_stop:
978 hid_hw_stop(hdev);
979 return ret;
980}
981
982static void cp2112_remove(struct hid_device *hdev)
983{
984 struct cp2112_device *dev = hid_get_drvdata(hdev);
985
986 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
987 if (gpiochip_remove(&dev->gc))
988 hid_err(hdev, "unable to remove gpio chip\n");
989 i2c_del_adapter(&dev->adap);
990 /* i2c_del_adapter has finished removing all i2c devices from our
991 * adapter. Well behaved devices should no longer call our cp2112_xfer
992 * and should have waited for any pending calls to finish. It has also
993 * waited for device_unregister(&adap->dev) to complete. Therefore we
994 * can safely free our struct cp2112_device.
995 */
996 hid_hw_close(hdev);
997 hid_hw_stop(hdev);
998 kfree(dev);
999}
1000
1001static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1002 u8 *data, int size)
1003{
1004 struct cp2112_device *dev = hid_get_drvdata(hdev);
1005 struct cp2112_xfer_status_report *xfer = (void *)data;
1006
1007 switch (data[0]) {
1008 case CP2112_TRANSFER_STATUS_RESPONSE:
1009 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1010 xfer->status0, xfer->status1,
1011 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1012
1013 switch (xfer->status0) {
1014 case STATUS0_IDLE:
1015 dev->xfer_status = -EAGAIN;
1016 break;
1017 case STATUS0_BUSY:
1018 dev->xfer_status = -EBUSY;
1019 break;
1020 case STATUS0_COMPLETE:
1021 dev->xfer_status = be16_to_cpu(xfer->length);
1022 break;
1023 case STATUS0_ERROR:
1024 switch (xfer->status1) {
1025 case STATUS1_TIMEOUT_NACK:
1026 case STATUS1_TIMEOUT_BUS:
1027 dev->xfer_status = -ETIMEDOUT;
1028 break;
1029 default:
1030 dev->xfer_status = -EIO;
1031 break;
1032 }
1033 break;
1034 default:
1035 dev->xfer_status = -EINVAL;
1036 break;
1037 }
1038
1039 atomic_set(&dev->xfer_avail, 1);
1040 break;
1041 case CP2112_DATA_READ_RESPONSE:
1042 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1043
1044 dev->read_length = data[2];
1045 if (dev->read_length > sizeof(dev->read_data))
1046 dev->read_length = sizeof(dev->read_data);
1047
1048 memcpy(dev->read_data, &data[3], dev->read_length);
1049 atomic_set(&dev->read_avail, 1);
1050 break;
1051 default:
1052 hid_err(hdev, "unknown report\n");
1053
1054 return 0;
1055 }
1056
1057 wake_up_interruptible(&dev->wait);
1058 return 1;
1059}
1060
1061static struct hid_driver cp2112_driver = {
1062 .name = "cp2112",
1063 .id_table = cp2112_devices,
1064 .probe = cp2112_probe,
1065 .remove = cp2112_remove,
1066 .raw_event = cp2112_raw_event,
1067};
1068
1069module_hid_driver(cp2112_driver);
1070MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1071MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1072MODULE_LICENSE("GPL");
1073