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of: MSI: Simplify irqdomain lookup
[linux/fpc-iii.git] / drivers / hid / hid-cp2112.c
blob7afc3fcc122c476a42e20f1e85e1ed409c93a734
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
35 enum {
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
56 enum {
57 STATUS0_IDLE = 0x00,
58 STATUS0_BUSY = 0x01,
59 STATUS0_COMPLETE = 0x02,
60 STATUS0_ERROR = 0x03,
61 };
62
63 enum {
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
72 struct 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
83 struct 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
96 struct cp2112_read_req_report {
97 u8 report; /* CP2112_DATA_READ_REQUEST */
98 u8 slave_address;
99 __be16 length;
100 } __packed;
101
102 struct 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
110 struct 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
117 struct cp2112_force_read_report {
118 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
119 __be16 length;
120 } __packed;
121
122 struct 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
130 struct 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. */
141 static 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. */
145 static const int RESPONSE_TIMEOUT = 50;
146
147 static const struct hid_device_id cp2112_devices[] = {
148 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
149 { }
150 };
151 MODULE_DEVICE_TABLE(hid, cp2112_devices);
152
153 struct 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 u8 hwversion;
160 int xfer_status;
161 atomic_t read_avail;
162 atomic_t xfer_avail;
163 struct gpio_chip gc;
164 };
165
166 static int gpio_push_pull = 0xFF;
167 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
168 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
169
170 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
171 {
172 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
173 gc);
174 struct hid_device *hdev = dev->hdev;
175 u8 buf[5];
176 int ret;
177
178 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
179 sizeof(buf), HID_FEATURE_REPORT,
180 HID_REQ_GET_REPORT);
181 if (ret != sizeof(buf)) {
182 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
183 return ret;
184 }
185
186 buf[1] &= ~(1 << offset);
187 buf[2] = gpio_push_pull;
188
189 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf),
190 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
191 if (ret < 0) {
192 hid_err(hdev, "error setting GPIO config: %d\n", ret);
193 return ret;
194 }
195
196 return 0;
197 }
198
199 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
200 {
201 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
202 gc);
203 struct hid_device *hdev = dev->hdev;
204 u8 buf[3];
205 int ret;
206
207 buf[0] = CP2112_GPIO_SET;
208 buf[1] = value ? 0xff : 0;
209 buf[2] = 1 << offset;
210
211 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf, sizeof(buf),
212 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
213 if (ret < 0)
214 hid_err(hdev, "error setting GPIO values: %d\n", ret);
215 }
216
217 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned offset)
218 {
219 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
220 gc);
221 struct hid_device *hdev = dev->hdev;
222 u8 buf[2];
223 int ret;
224
225 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf, sizeof(buf),
226 HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
227 if (ret != sizeof(buf)) {
228 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
229 return ret;
230 }
231
232 return (buf[1] >> offset) & 1;
233 }
234
235 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
236 unsigned offset, int value)
237 {
238 struct cp2112_device *dev = container_of(chip, struct cp2112_device,
239 gc);
240 struct hid_device *hdev = dev->hdev;
241 u8 buf[5];
242 int ret;
243
244 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
245 sizeof(buf), HID_FEATURE_REPORT,
246 HID_REQ_GET_REPORT);
247 if (ret != sizeof(buf)) {
248 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
249 return ret;
250 }
251
252 buf[1] |= 1 << offset;
253 buf[2] = gpio_push_pull;
254
255 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf),
256 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
257 if (ret < 0) {
258 hid_err(hdev, "error setting GPIO config: %d\n", ret);
259 return ret;
260 }
261
262 /*
263 * Set gpio value when output direction is already set,
264 * as specified in AN495, Rev. 0.2, cpt. 4.4
265 */
266 cp2112_gpio_set(chip, offset, value);
267
268 return 0;
269 }
270
271 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
272 u8 *data, size_t count, unsigned char report_type)
273 {
274 u8 *buf;
275 int ret;
276
277 buf = kmalloc(count, GFP_KERNEL);
278 if (!buf)
279 return -ENOMEM;
280
281 ret = hid_hw_raw_request(hdev, report_number, buf, count,
282 report_type, HID_REQ_GET_REPORT);
283 memcpy(data, buf, count);
284 kfree(buf);
285 return ret;
286 }
287
288 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
289 unsigned char report_type)
290 {
291 u8 *buf;
292 int ret;
293
294 buf = kmemdup(data, count, GFP_KERNEL);
295 if (!buf)
296 return -ENOMEM;
297
298 if (report_type == HID_OUTPUT_REPORT)
299 ret = hid_hw_output_report(hdev, buf, count);
300 else
301 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
302 HID_REQ_SET_REPORT);
303
304 kfree(buf);
305 return ret;
306 }
307
308 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
309 {
310 int ret = 0;
311
312 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
313 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
314 * come in cp2112_raw_event or timeout. There will only be one of these
315 * in flight at any one time. The timeout is extremely large and is a
316 * last resort if the CP2112 has died. If we do timeout we don't expect
317 * to receive the response which would cause data races, it's not like
318 * we can do anything about it anyway.
319 */
320 ret = wait_event_interruptible_timeout(dev->wait,
321 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
322 if (-ERESTARTSYS == ret)
323 return ret;
324 if (!ret)
325 return -ETIMEDOUT;
326
327 atomic_set(avail, 0);
328 return 0;
329 }
330
331 static int cp2112_xfer_status(struct cp2112_device *dev)
332 {
333 struct hid_device *hdev = dev->hdev;
334 u8 buf[2];
335 int ret;
336
337 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
338 buf[1] = 0x01;
339 atomic_set(&dev->xfer_avail, 0);
340
341 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
342 if (ret < 0) {
343 hid_warn(hdev, "Error requesting status: %d\n", ret);
344 return ret;
345 }
346
347 ret = cp2112_wait(dev, &dev->xfer_avail);
348 if (ret)
349 return ret;
350
351 return dev->xfer_status;
352 }
353
354 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
355 {
356 struct hid_device *hdev = dev->hdev;
357 struct cp2112_force_read_report report;
358 int ret;
359
360 if (size > sizeof(dev->read_data))
361 size = sizeof(dev->read_data);
362 report.report = CP2112_DATA_READ_FORCE_SEND;
363 report.length = cpu_to_be16(size);
364
365 atomic_set(&dev->read_avail, 0);
366
367 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
368 HID_OUTPUT_REPORT);
369 if (ret < 0) {
370 hid_warn(hdev, "Error requesting data: %d\n", ret);
371 return ret;
372 }
373
374 ret = cp2112_wait(dev, &dev->read_avail);
375 if (ret)
376 return ret;
377
378 hid_dbg(hdev, "read %d of %zd bytes requested\n",
379 dev->read_length, size);
380
381 if (size > dev->read_length)
382 size = dev->read_length;
383
384 memcpy(data, dev->read_data, size);
385 return dev->read_length;
386 }
387
388 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
389 {
390 struct cp2112_read_req_report *report = buf;
391
392 if (length < 1 || length > 512)
393 return -EINVAL;
394
395 report->report = CP2112_DATA_READ_REQUEST;
396 report->slave_address = slave_address << 1;
397 report->length = cpu_to_be16(length);
398 return sizeof(*report);
399 }
400
401 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
402 u8 command, u8 *data, u8 data_length)
403 {
404 struct cp2112_write_read_req_report *report = buf;
405
406 if (length < 1 || length > 512
407 || data_length > sizeof(report->target_address) - 1)
408 return -EINVAL;
409
410 report->report = CP2112_DATA_WRITE_READ_REQUEST;
411 report->slave_address = slave_address << 1;
412 report->length = cpu_to_be16(length);
413 report->target_address_length = data_length + 1;
414 report->target_address[0] = command;
415 memcpy(&report->target_address[1], data, data_length);
416 return data_length + 6;
417 }
418
419 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
420 u8 data_length)
421 {
422 struct cp2112_write_req_report *report = buf;
423
424 if (data_length > sizeof(report->data) - 1)
425 return -EINVAL;
426
427 report->report = CP2112_DATA_WRITE_REQUEST;
428 report->slave_address = slave_address << 1;
429 report->length = data_length + 1;
430 report->data[0] = command;
431 memcpy(&report->data[1], data, data_length);
432 return data_length + 4;
433 }
434
435 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
436 u8 data_length)
437 {
438 struct cp2112_write_req_report *report = buf;
439
440 if (data_length > sizeof(report->data))
441 return -EINVAL;
442
443 report->report = CP2112_DATA_WRITE_REQUEST;
444 report->slave_address = slave_address << 1;
445 report->length = data_length;
446 memcpy(report->data, data, data_length);
447 return data_length + 3;
448 }
449
450 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
451 u8 *addr, int addr_length,
452 int read_length)
453 {
454 struct cp2112_write_read_req_report *report = buf;
455
456 if (read_length < 1 || read_length > 512 ||
457 addr_length > sizeof(report->target_address))
458 return -EINVAL;
459
460 report->report = CP2112_DATA_WRITE_READ_REQUEST;
461 report->slave_address = slave_address << 1;
462 report->length = cpu_to_be16(read_length);
463 report->target_address_length = addr_length;
464 memcpy(report->target_address, addr, addr_length);
465 return addr_length + 5;
466 }
467
468 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
469 int num)
470 {
471 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
472 struct hid_device *hdev = dev->hdev;
473 u8 buf[64];
474 ssize_t count;
475 ssize_t read_length = 0;
476 u8 *read_buf = NULL;
477 unsigned int retries;
478 int ret;
479
480 hid_dbg(hdev, "I2C %d messages\n", num);
481
482 if (num == 1) {
483 if (msgs->flags & I2C_M_RD) {
484 hid_dbg(hdev, "I2C read %#04x len %d\n",
485 msgs->addr, msgs->len);
486 read_length = msgs->len;
487 read_buf = msgs->buf;
488 count = cp2112_read_req(buf, msgs->addr, msgs->len);
489 } else {
490 hid_dbg(hdev, "I2C write %#04x len %d\n",
491 msgs->addr, msgs->len);
492 count = cp2112_i2c_write_req(buf, msgs->addr,
493 msgs->buf, msgs->len);
494 }
495 if (count < 0)
496 return count;
497 } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */
498 num == 2 &&
499 msgs[0].addr == msgs[1].addr &&
500 !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
501 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
502 msgs[0].addr, msgs[0].len, msgs[1].len);
503 read_length = msgs[1].len;
504 read_buf = msgs[1].buf;
505 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
506 msgs[0].buf, msgs[0].len, msgs[1].len);
507 if (count < 0)
508 return count;
509 } else {
510 hid_err(hdev,
511 "Multi-message I2C transactions not supported\n");
512 return -EOPNOTSUPP;
513 }
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 for (count = 0; count < read_length;) {
551 ret = cp2112_read(dev, read_buf + count, read_length - count);
552 if (ret < 0)
553 goto power_normal;
554 if (ret == 0) {
555 hid_err(hdev, "read returned 0\n");
556 ret = -EIO;
557 goto power_normal;
558 }
559 count += ret;
560 if (count > read_length) {
561 /*
562 * The hardware returned too much data.
563 * This is mostly harmless because cp2112_read()
564 * has a limit check so didn't overrun our
565 * buffer. Nevertheless, we return an error
566 * because something is seriously wrong and
567 * it shouldn't go unnoticed.
568 */
569 hid_err(hdev, "long read: %d > %zd\n",
570 ret, read_length - count + ret);
571 ret = -EIO;
572 goto power_normal;
573 }
574 }
575
576 /* return the number of transferred messages */
577 ret = num;
578
579 power_normal:
580 hid_hw_power(hdev, PM_HINT_NORMAL);
581 hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
582 return ret;
583 }
584
585 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
586 unsigned short flags, char read_write, u8 command,
587 int size, union i2c_smbus_data *data)
588 {
589 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
590 struct hid_device *hdev = dev->hdev;
591 u8 buf[64];
592 __le16 word;
593 ssize_t count;
594 size_t read_length = 0;
595 unsigned int retries;
596 int ret;
597
598 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
599 read_write == I2C_SMBUS_WRITE ? "write" : "read",
600 addr, flags, command, size);
601
602 switch (size) {
603 case I2C_SMBUS_BYTE:
604 read_length = 1;
605
606 if (I2C_SMBUS_READ == read_write)
607 count = cp2112_read_req(buf, addr, read_length);
608 else
609 count = cp2112_write_req(buf, addr, command, NULL,
610 0);
611 break;
612 case I2C_SMBUS_BYTE_DATA:
613 read_length = 1;
614
615 if (I2C_SMBUS_READ == read_write)
616 count = cp2112_write_read_req(buf, addr, read_length,
617 command, NULL, 0);
618 else
619 count = cp2112_write_req(buf, addr, command,
620 &data->byte, 1);
621 break;
622 case I2C_SMBUS_WORD_DATA:
623 read_length = 2;
624 word = cpu_to_le16(data->word);
625
626 if (I2C_SMBUS_READ == read_write)
627 count = cp2112_write_read_req(buf, addr, read_length,
628 command, NULL, 0);
629 else
630 count = cp2112_write_req(buf, addr, command,
631 (u8 *)&word, 2);
632 break;
633 case I2C_SMBUS_PROC_CALL:
634 size = I2C_SMBUS_WORD_DATA;
635 read_write = I2C_SMBUS_READ;
636 read_length = 2;
637 word = cpu_to_le16(data->word);
638
639 count = cp2112_write_read_req(buf, addr, read_length, command,
640 (u8 *)&word, 2);
641 break;
642 case I2C_SMBUS_I2C_BLOCK_DATA:
643 size = I2C_SMBUS_BLOCK_DATA;
644 /* fallthrough */
645 case I2C_SMBUS_BLOCK_DATA:
646 if (I2C_SMBUS_READ == read_write) {
647 count = cp2112_write_read_req(buf, addr,
648 I2C_SMBUS_BLOCK_MAX,
649 command, NULL, 0);
650 } else {
651 count = cp2112_write_req(buf, addr, command,
652 data->block,
653 data->block[0] + 1);
654 }
655 break;
656 case I2C_SMBUS_BLOCK_PROC_CALL:
657 size = I2C_SMBUS_BLOCK_DATA;
658 read_write = I2C_SMBUS_READ;
659
660 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
661 command, data->block,
662 data->block[0] + 1);
663 break;
664 default:
665 hid_warn(hdev, "Unsupported transaction %d\n", size);
666 return -EOPNOTSUPP;
667 }
668
669 if (count < 0)
670 return count;
671
672 ret = hid_hw_power(hdev, PM_HINT_FULLON);
673 if (ret < 0) {
674 hid_err(hdev, "power management error: %d\n", ret);
675 return ret;
676 }
677
678 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
679 if (ret < 0) {
680 hid_warn(hdev, "Error starting transaction: %d\n", ret);
681 goto power_normal;
682 }
683
684 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
685 ret = cp2112_xfer_status(dev);
686 if (-EBUSY == ret)
687 continue;
688 if (ret < 0)
689 goto power_normal;
690 break;
691 }
692
693 if (XFER_STATUS_RETRIES <= retries) {
694 hid_warn(hdev, "Transfer timed out, cancelling.\n");
695 buf[0] = CP2112_CANCEL_TRANSFER;
696 buf[1] = 0x01;
697
698 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
699 if (ret < 0)
700 hid_warn(hdev, "Error cancelling transaction: %d\n",
701 ret);
702
703 ret = -ETIMEDOUT;
704 goto power_normal;
705 }
706
707 if (I2C_SMBUS_WRITE == read_write) {
708 ret = 0;
709 goto power_normal;
710 }
711
712 if (I2C_SMBUS_BLOCK_DATA == size)
713 read_length = ret;
714
715 ret = cp2112_read(dev, buf, read_length);
716 if (ret < 0)
717 goto power_normal;
718 if (ret != read_length) {
719 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
720 ret = -EIO;
721 goto power_normal;
722 }
723
724 switch (size) {
725 case I2C_SMBUS_BYTE:
726 case I2C_SMBUS_BYTE_DATA:
727 data->byte = buf[0];
728 break;
729 case I2C_SMBUS_WORD_DATA:
730 data->word = le16_to_cpup((__le16 *)buf);
731 break;
732 case I2C_SMBUS_BLOCK_DATA:
733 if (read_length > I2C_SMBUS_BLOCK_MAX) {
734 ret = -EPROTO;
735 goto power_normal;
736 }
737
738 memcpy(data->block, buf, read_length);
739 break;
740 }
741
742 ret = 0;
743 power_normal:
744 hid_hw_power(hdev, PM_HINT_NORMAL);
745 hid_dbg(hdev, "transfer finished: %d\n", ret);
746 return ret;
747 }
748
749 static u32 cp2112_functionality(struct i2c_adapter *adap)
750 {
751 return I2C_FUNC_I2C |
752 I2C_FUNC_SMBUS_BYTE |
753 I2C_FUNC_SMBUS_BYTE_DATA |
754 I2C_FUNC_SMBUS_WORD_DATA |
755 I2C_FUNC_SMBUS_BLOCK_DATA |
756 I2C_FUNC_SMBUS_I2C_BLOCK |
757 I2C_FUNC_SMBUS_PROC_CALL |
758 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
759 }
760
761 static const struct i2c_algorithm smbus_algorithm = {
762 .master_xfer = cp2112_i2c_xfer,
763 .smbus_xfer = cp2112_xfer,
764 .functionality = cp2112_functionality,
765 };
766
767 static int cp2112_get_usb_config(struct hid_device *hdev,
768 struct cp2112_usb_config_report *cfg)
769 {
770 int ret;
771
772 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
773 HID_FEATURE_REPORT);
774 if (ret != sizeof(*cfg)) {
775 hid_err(hdev, "error reading usb config: %d\n", ret);
776 if (ret < 0)
777 return ret;
778 return -EIO;
779 }
780
781 return 0;
782 }
783
784 static int cp2112_set_usb_config(struct hid_device *hdev,
785 struct cp2112_usb_config_report *cfg)
786 {
787 int ret;
788
789 BUG_ON(cfg->report != CP2112_USB_CONFIG);
790
791 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
792 HID_FEATURE_REPORT);
793 if (ret != sizeof(*cfg)) {
794 hid_err(hdev, "error writing usb config: %d\n", ret);
795 if (ret < 0)
796 return ret;
797 return -EIO;
798 }
799
800 return 0;
801 }
802
803 static void chmod_sysfs_attrs(struct hid_device *hdev);
804
805 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
806 static ssize_t name##_store(struct device *kdev, \
807 struct device_attribute *attr, const char *buf, \
808 size_t count) \
809 { \
810 struct hid_device *hdev = container_of(kdev, struct hid_device, dev); \
811 struct cp2112_usb_config_report cfg; \
812 int ret = cp2112_get_usb_config(hdev, &cfg); \
813 if (ret) \
814 return ret; \
815 store; \
816 ret = cp2112_set_usb_config(hdev, &cfg); \
817 if (ret) \
818 return ret; \
819 chmod_sysfs_attrs(hdev); \
820 return count; \
821 } \
822 static ssize_t name##_show(struct device *kdev, \
823 struct device_attribute *attr, char *buf) \
824 { \
825 struct hid_device *hdev = container_of(kdev, struct hid_device, dev); \
826 struct cp2112_usb_config_report cfg; \
827 int ret = cp2112_get_usb_config(hdev, &cfg); \
828 if (ret) \
829 return ret; \
830 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
831 } \
832 static DEVICE_ATTR_RW(name);
833
834 CP2112_CONFIG_ATTR(vendor_id, ({
835 u16 vid;
836
837 if (sscanf(buf, "%hi", &vid) != 1)
838 return -EINVAL;
839
840 cfg.vid = cpu_to_le16(vid);
841 cfg.mask = 0x01;
842 }), "0x%04x\n", le16_to_cpu(cfg.vid));
843
844 CP2112_CONFIG_ATTR(product_id, ({
845 u16 pid;
846
847 if (sscanf(buf, "%hi", &pid) != 1)
848 return -EINVAL;
849
850 cfg.pid = cpu_to_le16(pid);
851 cfg.mask = 0x02;
852 }), "0x%04x\n", le16_to_cpu(cfg.pid));
853
854 CP2112_CONFIG_ATTR(max_power, ({
855 int mA;
856
857 if (sscanf(buf, "%i", &mA) != 1)
858 return -EINVAL;
859
860 cfg.max_power = (mA + 1) / 2;
861 cfg.mask = 0x04;
862 }), "%u mA\n", cfg.max_power * 2);
863
864 CP2112_CONFIG_ATTR(power_mode, ({
865 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
866 return -EINVAL;
867
868 cfg.mask = 0x08;
869 }), "%u\n", cfg.power_mode);
870
871 CP2112_CONFIG_ATTR(release_version, ({
872 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
873 != 2)
874 return -EINVAL;
875
876 cfg.mask = 0x10;
877 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
878
879 #undef CP2112_CONFIG_ATTR
880
881 struct cp2112_pstring_attribute {
882 struct device_attribute attr;
883 unsigned char report;
884 };
885
886 static ssize_t pstr_store(struct device *kdev,
887 struct device_attribute *kattr, const char *buf,
888 size_t count)
889 {
890 struct hid_device *hdev = container_of(kdev, struct hid_device, dev);
891 struct cp2112_pstring_attribute *attr =
892 container_of(kattr, struct cp2112_pstring_attribute, attr);
893 struct cp2112_string_report report;
894 int ret;
895
896 memset(&report, 0, sizeof(report));
897
898 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
899 report.string, ARRAY_SIZE(report.string));
900 report.report = attr->report;
901 report.length = ret * sizeof(report.string[0]) + 2;
902 report.type = USB_DT_STRING;
903
904 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
905 HID_FEATURE_REPORT);
906 if (ret != report.length + 1) {
907 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
908 ret);
909 if (ret < 0)
910 return ret;
911 return -EIO;
912 }
913
914 chmod_sysfs_attrs(hdev);
915 return count;
916 }
917
918 static ssize_t pstr_show(struct device *kdev,
919 struct device_attribute *kattr, char *buf)
920 {
921 struct hid_device *hdev = container_of(kdev, struct hid_device, dev);
922 struct cp2112_pstring_attribute *attr =
923 container_of(kattr, struct cp2112_pstring_attribute, attr);
924 struct cp2112_string_report report;
925 u8 length;
926 int ret;
927
928 ret = cp2112_hid_get(hdev, attr->report, &report.report,
929 sizeof(report) - 1, HID_FEATURE_REPORT);
930 if (ret < 3) {
931 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
932 ret);
933 if (ret < 0)
934 return ret;
935 return -EIO;
936 }
937
938 if (report.length < 2) {
939 hid_err(hdev, "invalid %s string length: %d\n",
940 kattr->attr.name, report.length);
941 return -EIO;
942 }
943
944 length = report.length > ret - 1 ? ret - 1 : report.length;
945 length = (length - 2) / sizeof(report.string[0]);
946 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
947 PAGE_SIZE - 1);
948 buf[ret++] = '\n';
949 return ret;
950 }
951
952 #define CP2112_PSTR_ATTR(name, _report) \
953 static struct cp2112_pstring_attribute dev_attr_##name = { \
954 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
955 .report = _report, \
956 };
957
958 CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
959 CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
960 CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
961
962 #undef CP2112_PSTR_ATTR
963
964 static const struct attribute_group cp2112_attr_group = {
965 .attrs = (struct attribute *[]){
966 &dev_attr_vendor_id.attr,
967 &dev_attr_product_id.attr,
968 &dev_attr_max_power.attr,
969 &dev_attr_power_mode.attr,
970 &dev_attr_release_version.attr,
971 &dev_attr_manufacturer.attr.attr,
972 &dev_attr_product.attr.attr,
973 &dev_attr_serial.attr.attr,
974 NULL
975 }
976 };
977
978 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
979 * PROM have already been programmed. We do not depend on this preventing
980 * writing to these attributes since the CP2112 will simply ignore writes to
981 * already-programmed fields. This is why there is no sense in fixing this
982 * racy behaviour.
983 */
984 static void chmod_sysfs_attrs(struct hid_device *hdev)
985 {
986 struct attribute **attr;
987 u8 buf[2];
988 int ret;
989
990 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
991 HID_FEATURE_REPORT);
992 if (ret != sizeof(buf)) {
993 hid_err(hdev, "error reading lock byte: %d\n", ret);
994 return;
995 }
996
997 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
998 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
999 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1000 if (ret < 0)
1001 hid_err(hdev, "error chmoding sysfs file %s\n",
1002 (*attr)->name);
1003 buf[1] >>= 1;
1004 }
1005 }
1006
1007 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1008 {
1009 struct cp2112_device *dev;
1010 u8 buf[3];
1011 struct cp2112_smbus_config_report config;
1012 int ret;
1013
1014 ret = hid_parse(hdev);
1015 if (ret) {
1016 hid_err(hdev, "parse failed\n");
1017 return ret;
1018 }
1019
1020 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1021 if (ret) {
1022 hid_err(hdev, "hw start failed\n");
1023 return ret;
1024 }
1025
1026 ret = hid_hw_open(hdev);
1027 if (ret) {
1028 hid_err(hdev, "hw open failed\n");
1029 goto err_hid_stop;
1030 }
1031
1032 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1033 if (ret < 0) {
1034 hid_err(hdev, "power management error: %d\n", ret);
1035 goto err_hid_close;
1036 }
1037
1038 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1039 HID_FEATURE_REPORT);
1040 if (ret != sizeof(buf)) {
1041 hid_err(hdev, "error requesting version\n");
1042 if (ret >= 0)
1043 ret = -EIO;
1044 goto err_power_normal;
1045 }
1046
1047 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1048 buf[1], buf[2]);
1049
1050 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1051 sizeof(config), HID_FEATURE_REPORT);
1052 if (ret != sizeof(config)) {
1053 hid_err(hdev, "error requesting SMBus config\n");
1054 if (ret >= 0)
1055 ret = -EIO;
1056 goto err_power_normal;
1057 }
1058
1059 config.retry_time = cpu_to_be16(1);
1060
1061 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1062 HID_FEATURE_REPORT);
1063 if (ret != sizeof(config)) {
1064 hid_err(hdev, "error setting SMBus config\n");
1065 if (ret >= 0)
1066 ret = -EIO;
1067 goto err_power_normal;
1068 }
1069
1070 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1071 if (!dev) {
1072 ret = -ENOMEM;
1073 goto err_power_normal;
1074 }
1075
1076 hid_set_drvdata(hdev, (void *)dev);
1077 dev->hdev = hdev;
1078 dev->adap.owner = THIS_MODULE;
1079 dev->adap.class = I2C_CLASS_HWMON;
1080 dev->adap.algo = &smbus_algorithm;
1081 dev->adap.algo_data = dev;
1082 dev->adap.dev.parent = &hdev->dev;
1083 snprintf(dev->adap.name, sizeof(dev->adap.name),
1084 "CP2112 SMBus Bridge on hiddev%d", hdev->minor);
1085 dev->hwversion = buf[2];
1086 init_waitqueue_head(&dev->wait);
1087
1088 hid_device_io_start(hdev);
1089 ret = i2c_add_adapter(&dev->adap);
1090 hid_device_io_stop(hdev);
1091
1092 if (ret) {
1093 hid_err(hdev, "error registering i2c adapter\n");
1094 goto err_free_dev;
1095 }
1096
1097 hid_dbg(hdev, "adapter registered\n");
1098
1099 dev->gc.label = "cp2112_gpio";
1100 dev->gc.direction_input = cp2112_gpio_direction_input;
1101 dev->gc.direction_output = cp2112_gpio_direction_output;
1102 dev->gc.set = cp2112_gpio_set;
1103 dev->gc.get = cp2112_gpio_get;
1104 dev->gc.base = -1;
1105 dev->gc.ngpio = 8;
1106 dev->gc.can_sleep = 1;
1107 dev->gc.dev = &hdev->dev;
1108
1109 ret = gpiochip_add(&dev->gc);
1110 if (ret < 0) {
1111 hid_err(hdev, "error registering gpio chip\n");
1112 goto err_free_i2c;
1113 }
1114
1115 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1116 if (ret < 0) {
1117 hid_err(hdev, "error creating sysfs attrs\n");
1118 goto err_gpiochip_remove;
1119 }
1120
1121 chmod_sysfs_attrs(hdev);
1122 hid_hw_power(hdev, PM_HINT_NORMAL);
1123
1124 return ret;
1125
1126 err_gpiochip_remove:
1127 gpiochip_remove(&dev->gc);
1128 err_free_i2c:
1129 i2c_del_adapter(&dev->adap);
1130 err_free_dev:
1131 kfree(dev);
1132 err_power_normal:
1133 hid_hw_power(hdev, PM_HINT_NORMAL);
1134 err_hid_close:
1135 hid_hw_close(hdev);
1136 err_hid_stop:
1137 hid_hw_stop(hdev);
1138 return ret;
1139 }
1140
1141 static void cp2112_remove(struct hid_device *hdev)
1142 {
1143 struct cp2112_device *dev = hid_get_drvdata(hdev);
1144
1145 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1146 gpiochip_remove(&dev->gc);
1147 i2c_del_adapter(&dev->adap);
1148 /* i2c_del_adapter has finished removing all i2c devices from our
1149 * adapter. Well behaved devices should no longer call our cp2112_xfer
1150 * and should have waited for any pending calls to finish. It has also
1151 * waited for device_unregister(&adap->dev) to complete. Therefore we
1152 * can safely free our struct cp2112_device.
1153 */
1154 hid_hw_close(hdev);
1155 hid_hw_stop(hdev);
1156 kfree(dev);
1157 }
1158
1159 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1160 u8 *data, int size)
1161 {
1162 struct cp2112_device *dev = hid_get_drvdata(hdev);
1163 struct cp2112_xfer_status_report *xfer = (void *)data;
1164
1165 switch (data[0]) {
1166 case CP2112_TRANSFER_STATUS_RESPONSE:
1167 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1168 xfer->status0, xfer->status1,
1169 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1170
1171 switch (xfer->status0) {
1172 case STATUS0_IDLE:
1173 dev->xfer_status = -EAGAIN;
1174 break;
1175 case STATUS0_BUSY:
1176 dev->xfer_status = -EBUSY;
1177 break;
1178 case STATUS0_COMPLETE:
1179 dev->xfer_status = be16_to_cpu(xfer->length);
1180 break;
1181 case STATUS0_ERROR:
1182 switch (xfer->status1) {
1183 case STATUS1_TIMEOUT_NACK:
1184 case STATUS1_TIMEOUT_BUS:
1185 dev->xfer_status = -ETIMEDOUT;
1186 break;
1187 default:
1188 dev->xfer_status = -EIO;
1189 break;
1190 }
1191 break;
1192 default:
1193 dev->xfer_status = -EINVAL;
1194 break;
1195 }
1196
1197 atomic_set(&dev->xfer_avail, 1);
1198 break;
1199 case CP2112_DATA_READ_RESPONSE:
1200 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1201
1202 dev->read_length = data[2];
1203 if (dev->read_length > sizeof(dev->read_data))
1204 dev->read_length = sizeof(dev->read_data);
1205
1206 memcpy(dev->read_data, &data[3], dev->read_length);
1207 atomic_set(&dev->read_avail, 1);
1208 break;
1209 default:
1210 hid_err(hdev, "unknown report\n");
1211
1212 return 0;
1213 }
1214
1215 wake_up_interruptible(&dev->wait);
1216 return 1;
1217 }
1218
1219 static struct hid_driver cp2112_driver = {
1220 .name = "cp2112",
1221 .id_table = cp2112_devices,
1222 .probe = cp2112_probe,
1223 .remove = cp2112_remove,
1224 .raw_event = cp2112_raw_event,
1225 };
1226
1227 module_hid_driver(cp2112_driver);
1228 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1229 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1230 MODULE_LICENSE("GPL");
1231
Linux with added FPC-III support