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 * https://www.silabs.com/documents/public/application-notes/an495-cp2112-interface-specification.pdf
25 */
26
27 #include <linux/gpio.h>
28 #include <linux/gpio/driver.h>
29 #include <linux/hid.h>
30 #include <linux/hidraw.h>
31 #include <linux/i2c.h>
32 #include <linux/module.h>
33 #include <linux/nls.h>
34 #include <linux/usb/ch9.h>
35 #include "hid-ids.h"
36
37 #define CP2112_REPORT_MAX_LENGTH 64
38 #define CP2112_GPIO_CONFIG_LENGTH 5
39 #define CP2112_GPIO_GET_LENGTH 2
40 #define CP2112_GPIO_SET_LENGTH 3
41
42 enum {
43 CP2112_GPIO_CONFIG = 0x02,
44 CP2112_GPIO_GET = 0x03,
45 CP2112_GPIO_SET = 0x04,
46 CP2112_GET_VERSION_INFO = 0x05,
47 CP2112_SMBUS_CONFIG = 0x06,
48 CP2112_DATA_READ_REQUEST = 0x10,
49 CP2112_DATA_WRITE_READ_REQUEST = 0x11,
50 CP2112_DATA_READ_FORCE_SEND = 0x12,
51 CP2112_DATA_READ_RESPONSE = 0x13,
52 CP2112_DATA_WRITE_REQUEST = 0x14,
53 CP2112_TRANSFER_STATUS_REQUEST = 0x15,
54 CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
55 CP2112_CANCEL_TRANSFER = 0x17,
56 CP2112_LOCK_BYTE = 0x20,
57 CP2112_USB_CONFIG = 0x21,
58 CP2112_MANUFACTURER_STRING = 0x22,
59 CP2112_PRODUCT_STRING = 0x23,
60 CP2112_SERIAL_STRING = 0x24,
61 };
62
63 enum {
64 STATUS0_IDLE = 0x00,
65 STATUS0_BUSY = 0x01,
66 STATUS0_COMPLETE = 0x02,
67 STATUS0_ERROR = 0x03,
68 };
69
70 enum {
71 STATUS1_TIMEOUT_NACK = 0x00,
72 STATUS1_TIMEOUT_BUS = 0x01,
73 STATUS1_ARBITRATION_LOST = 0x02,
74 STATUS1_READ_INCOMPLETE = 0x03,
75 STATUS1_WRITE_INCOMPLETE = 0x04,
76 STATUS1_SUCCESS = 0x05,
77 };
78
79 struct cp2112_smbus_config_report {
80 u8 report; /* CP2112_SMBUS_CONFIG */
81 __be32 clock_speed; /* Hz */
82 u8 device_address; /* Stored in the upper 7 bits */
83 u8 auto_send_read; /* 1 = enabled, 0 = disabled */
84 __be16 write_timeout; /* ms, 0 = no timeout */
85 __be16 read_timeout; /* ms, 0 = no timeout */
86 u8 scl_low_timeout; /* 1 = enabled, 0 = disabled */
87 __be16 retry_time; /* # of retries, 0 = no limit */
88 } __packed;
89
90 struct cp2112_usb_config_report {
91 u8 report; /* CP2112_USB_CONFIG */
92 __le16 vid; /* Vendor ID */
93 __le16 pid; /* Product ID */
94 u8 max_power; /* Power requested in 2mA units */
95 u8 power_mode; /* 0x00 = bus powered
96 0x01 = self powered & regulator off
97 0x02 = self powered & regulator on */
98 u8 release_major;
99 u8 release_minor;
100 u8 mask; /* What fields to program */
101 } __packed;
102
103 struct cp2112_read_req_report {
104 u8 report; /* CP2112_DATA_READ_REQUEST */
105 u8 slave_address;
106 __be16 length;
107 } __packed;
108
109 struct cp2112_write_read_req_report {
110 u8 report; /* CP2112_DATA_WRITE_READ_REQUEST */
111 u8 slave_address;
112 __be16 length;
113 u8 target_address_length;
114 u8 target_address[16];
115 } __packed;
116
117 struct cp2112_write_req_report {
118 u8 report; /* CP2112_DATA_WRITE_REQUEST */
119 u8 slave_address;
120 u8 length;
121 u8 data[61];
122 } __packed;
123
124 struct cp2112_force_read_report {
125 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
126 __be16 length;
127 } __packed;
128
129 struct cp2112_xfer_status_report {
130 u8 report; /* CP2112_TRANSFER_STATUS_RESPONSE */
131 u8 status0; /* STATUS0_* */
132 u8 status1; /* STATUS1_* */
133 __be16 retries;
134 __be16 length;
135 } __packed;
136
137 struct cp2112_string_report {
138 u8 dummy; /* force .string to be aligned */
139 u8 report; /* CP2112_*_STRING */
140 u8 length; /* length in bytes of everyting after .report */
141 u8 type; /* USB_DT_STRING */
142 wchar_t string[30]; /* UTF16_LITTLE_ENDIAN string */
143 } __packed;
144
145 /* Number of times to request transfer status before giving up waiting for a
146 transfer to complete. This may need to be changed if SMBUS clock, retries,
147 or read/write/scl_low timeout settings are changed. */
148 static const int XFER_STATUS_RETRIES = 10;
149
150 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
151 CP2112_TRANSFER_STATUS_RESPONSE. */
152 static const int RESPONSE_TIMEOUT = 50;
153
154 static const struct hid_device_id cp2112_devices[] = {
155 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
156 { }
157 };
158 MODULE_DEVICE_TABLE(hid, cp2112_devices);
159
160 struct cp2112_device {
161 struct i2c_adapter adap;
162 struct hid_device *hdev;
163 wait_queue_head_t wait;
164 u8 read_data[61];
165 u8 read_length;
166 u8 hwversion;
167 int xfer_status;
168 atomic_t read_avail;
169 atomic_t xfer_avail;
170 struct gpio_chip gc;
171 u8 *in_out_buffer;
172 struct mutex lock;
173
174 struct gpio_desc *desc[8];
175 bool gpio_poll;
176 struct delayed_work gpio_poll_worker;
177 unsigned long irq_mask;
178 u8 gpio_prev_state;
179 };
180
181 static int gpio_push_pull = 0xFF;
182 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
183 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
184
cp2112_gpio_direction_input(struct gpio_chip * chip,unsigned offset)185 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
186 {
187 struct cp2112_device *dev = gpiochip_get_data(chip);
188 struct hid_device *hdev = dev->hdev;
189 u8 *buf = dev->in_out_buffer;
190 int ret;
191
192 mutex_lock(&dev->lock);
193
194 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
195 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
196 HID_REQ_GET_REPORT);
197 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
198 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
199 if (ret >= 0)
200 ret = -EIO;
201 goto exit;
202 }
203
204 buf[1] &= ~(1 << offset);
205 buf[2] = gpio_push_pull;
206
207 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
208 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
209 HID_REQ_SET_REPORT);
210 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
211 hid_err(hdev, "error setting GPIO config: %d\n", ret);
212 if (ret >= 0)
213 ret = -EIO;
214 goto exit;
215 }
216
217 ret = 0;
218
219 exit:
220 mutex_unlock(&dev->lock);
221 return ret;
222 }
223
cp2112_gpio_set(struct gpio_chip * chip,unsigned offset,int value)224 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
225 {
226 struct cp2112_device *dev = gpiochip_get_data(chip);
227 struct hid_device *hdev = dev->hdev;
228 u8 *buf = dev->in_out_buffer;
229 int ret;
230
231 mutex_lock(&dev->lock);
232
233 buf[0] = CP2112_GPIO_SET;
234 buf[1] = value ? 0xff : 0;
235 buf[2] = 1 << offset;
236
237 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
238 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
239 HID_REQ_SET_REPORT);
240 if (ret < 0)
241 hid_err(hdev, "error setting GPIO values: %d\n", ret);
242
243 mutex_unlock(&dev->lock);
244 }
245
cp2112_gpio_get_all(struct gpio_chip * chip)246 static int cp2112_gpio_get_all(struct gpio_chip *chip)
247 {
248 struct cp2112_device *dev = gpiochip_get_data(chip);
249 struct hid_device *hdev = dev->hdev;
250 u8 *buf = dev->in_out_buffer;
251 int ret;
252
253 mutex_lock(&dev->lock);
254
255 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
256 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
257 HID_REQ_GET_REPORT);
258 if (ret != CP2112_GPIO_GET_LENGTH) {
259 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
260 ret = ret < 0 ? ret : -EIO;
261 goto exit;
262 }
263
264 ret = buf[1];
265
266 exit:
267 mutex_unlock(&dev->lock);
268
269 return ret;
270 }
271
cp2112_gpio_get(struct gpio_chip * chip,unsigned int offset)272 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
273 {
274 int ret;
275
276 ret = cp2112_gpio_get_all(chip);
277 if (ret < 0)
278 return ret;
279
280 return (ret >> offset) & 1;
281 }
282
cp2112_gpio_direction_output(struct gpio_chip * chip,unsigned offset,int value)283 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
284 unsigned offset, int value)
285 {
286 struct cp2112_device *dev = gpiochip_get_data(chip);
287 struct hid_device *hdev = dev->hdev;
288 u8 *buf = dev->in_out_buffer;
289 int ret;
290
291 mutex_lock(&dev->lock);
292
293 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
294 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
295 HID_REQ_GET_REPORT);
296 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
297 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
298 goto fail;
299 }
300
301 buf[1] |= 1 << offset;
302 buf[2] = gpio_push_pull;
303
304 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
305 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
306 HID_REQ_SET_REPORT);
307 if (ret < 0) {
308 hid_err(hdev, "error setting GPIO config: %d\n", ret);
309 goto fail;
310 }
311
312 mutex_unlock(&dev->lock);
313
314 /*
315 * Set gpio value when output direction is already set,
316 * as specified in AN495, Rev. 0.2, cpt. 4.4
317 */
318 cp2112_gpio_set(chip, offset, value);
319
320 return 0;
321
322 fail:
323 mutex_unlock(&dev->lock);
324 return ret < 0 ? ret : -EIO;
325 }
326
cp2112_hid_get(struct hid_device * hdev,unsigned char report_number,u8 * data,size_t count,unsigned char report_type)327 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
328 u8 *data, size_t count, unsigned char report_type)
329 {
330 u8 *buf;
331 int ret;
332
333 buf = kmalloc(count, GFP_KERNEL);
334 if (!buf)
335 return -ENOMEM;
336
337 ret = hid_hw_raw_request(hdev, report_number, buf, count,
338 report_type, HID_REQ_GET_REPORT);
339 memcpy(data, buf, count);
340 kfree(buf);
341 return ret;
342 }
343
cp2112_hid_output(struct hid_device * hdev,u8 * data,size_t count,unsigned char report_type)344 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
345 unsigned char report_type)
346 {
347 u8 *buf;
348 int ret;
349
350 buf = kmemdup(data, count, GFP_KERNEL);
351 if (!buf)
352 return -ENOMEM;
353
354 if (report_type == HID_OUTPUT_REPORT)
355 ret = hid_hw_output_report(hdev, buf, count);
356 else
357 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
358 HID_REQ_SET_REPORT);
359
360 kfree(buf);
361 return ret;
362 }
363
cp2112_wait(struct cp2112_device * dev,atomic_t * avail)364 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
365 {
366 int ret = 0;
367
368 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
369 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
370 * come in cp2112_raw_event or timeout. There will only be one of these
371 * in flight at any one time. The timeout is extremely large and is a
372 * last resort if the CP2112 has died. If we do timeout we don't expect
373 * to receive the response which would cause data races, it's not like
374 * we can do anything about it anyway.
375 */
376 ret = wait_event_interruptible_timeout(dev->wait,
377 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
378 if (-ERESTARTSYS == ret)
379 return ret;
380 if (!ret)
381 return -ETIMEDOUT;
382
383 atomic_set(avail, 0);
384 return 0;
385 }
386
cp2112_xfer_status(struct cp2112_device * dev)387 static int cp2112_xfer_status(struct cp2112_device *dev)
388 {
389 struct hid_device *hdev = dev->hdev;
390 u8 buf[2];
391 int ret;
392
393 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
394 buf[1] = 0x01;
395 atomic_set(&dev->xfer_avail, 0);
396
397 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
398 if (ret < 0) {
399 hid_warn(hdev, "Error requesting status: %d\n", ret);
400 return ret;
401 }
402
403 ret = cp2112_wait(dev, &dev->xfer_avail);
404 if (ret)
405 return ret;
406
407 return dev->xfer_status;
408 }
409
cp2112_read(struct cp2112_device * dev,u8 * data,size_t size)410 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
411 {
412 struct hid_device *hdev = dev->hdev;
413 struct cp2112_force_read_report report;
414 int ret;
415
416 if (size > sizeof(dev->read_data))
417 size = sizeof(dev->read_data);
418 report.report = CP2112_DATA_READ_FORCE_SEND;
419 report.length = cpu_to_be16(size);
420
421 atomic_set(&dev->read_avail, 0);
422
423 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
424 HID_OUTPUT_REPORT);
425 if (ret < 0) {
426 hid_warn(hdev, "Error requesting data: %d\n", ret);
427 return ret;
428 }
429
430 ret = cp2112_wait(dev, &dev->read_avail);
431 if (ret)
432 return ret;
433
434 hid_dbg(hdev, "read %d of %zd bytes requested\n",
435 dev->read_length, size);
436
437 if (size > dev->read_length)
438 size = dev->read_length;
439
440 memcpy(data, dev->read_data, size);
441 return dev->read_length;
442 }
443
cp2112_read_req(void * buf,u8 slave_address,u16 length)444 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
445 {
446 struct cp2112_read_req_report *report = buf;
447
448 if (length < 1 || length > 512)
449 return -EINVAL;
450
451 report->report = CP2112_DATA_READ_REQUEST;
452 report->slave_address = slave_address << 1;
453 report->length = cpu_to_be16(length);
454 return sizeof(*report);
455 }
456
cp2112_write_read_req(void * buf,u8 slave_address,u16 length,u8 command,u8 * data,u8 data_length)457 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
458 u8 command, u8 *data, u8 data_length)
459 {
460 struct cp2112_write_read_req_report *report = buf;
461
462 if (length < 1 || length > 512
463 || data_length > sizeof(report->target_address) - 1)
464 return -EINVAL;
465
466 report->report = CP2112_DATA_WRITE_READ_REQUEST;
467 report->slave_address = slave_address << 1;
468 report->length = cpu_to_be16(length);
469 report->target_address_length = data_length + 1;
470 report->target_address[0] = command;
471 memcpy(&report->target_address[1], data, data_length);
472 return data_length + 6;
473 }
474
cp2112_write_req(void * buf,u8 slave_address,u8 command,u8 * data,u8 data_length)475 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
476 u8 data_length)
477 {
478 struct cp2112_write_req_report *report = buf;
479
480 if (data_length > sizeof(report->data) - 1)
481 return -EINVAL;
482
483 report->report = CP2112_DATA_WRITE_REQUEST;
484 report->slave_address = slave_address << 1;
485 report->length = data_length + 1;
486 report->data[0] = command;
487 memcpy(&report->data[1], data, data_length);
488 return data_length + 4;
489 }
490
cp2112_i2c_write_req(void * buf,u8 slave_address,u8 * data,u8 data_length)491 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
492 u8 data_length)
493 {
494 struct cp2112_write_req_report *report = buf;
495
496 if (data_length > sizeof(report->data))
497 return -EINVAL;
498
499 report->report = CP2112_DATA_WRITE_REQUEST;
500 report->slave_address = slave_address << 1;
501 report->length = data_length;
502 memcpy(report->data, data, data_length);
503 return data_length + 3;
504 }
505
cp2112_i2c_write_read_req(void * buf,u8 slave_address,u8 * addr,int addr_length,int read_length)506 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
507 u8 *addr, int addr_length,
508 int read_length)
509 {
510 struct cp2112_write_read_req_report *report = buf;
511
512 if (read_length < 1 || read_length > 512 ||
513 addr_length > sizeof(report->target_address))
514 return -EINVAL;
515
516 report->report = CP2112_DATA_WRITE_READ_REQUEST;
517 report->slave_address = slave_address << 1;
518 report->length = cpu_to_be16(read_length);
519 report->target_address_length = addr_length;
520 memcpy(report->target_address, addr, addr_length);
521 return addr_length + 5;
522 }
523
cp2112_i2c_xfer(struct i2c_adapter * adap,struct i2c_msg * msgs,int num)524 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
525 int num)
526 {
527 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
528 struct hid_device *hdev = dev->hdev;
529 u8 buf[64];
530 ssize_t count;
531 ssize_t read_length = 0;
532 u8 *read_buf = NULL;
533 unsigned int retries;
534 int ret;
535
536 hid_dbg(hdev, "I2C %d messages\n", num);
537
538 if (num == 1) {
539 if (msgs->flags & I2C_M_RD) {
540 hid_dbg(hdev, "I2C read %#04x len %d\n",
541 msgs->addr, msgs->len);
542 read_length = msgs->len;
543 read_buf = msgs->buf;
544 count = cp2112_read_req(buf, msgs->addr, msgs->len);
545 } else {
546 hid_dbg(hdev, "I2C write %#04x len %d\n",
547 msgs->addr, msgs->len);
548 count = cp2112_i2c_write_req(buf, msgs->addr,
549 msgs->buf, msgs->len);
550 }
551 if (count < 0)
552 return count;
553 } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */
554 num == 2 &&
555 msgs[0].addr == msgs[1].addr &&
556 !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
557 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
558 msgs[0].addr, msgs[0].len, msgs[1].len);
559 read_length = msgs[1].len;
560 read_buf = msgs[1].buf;
561 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
562 msgs[0].buf, msgs[0].len, msgs[1].len);
563 if (count < 0)
564 return count;
565 } else {
566 hid_err(hdev,
567 "Multi-message I2C transactions not supported\n");
568 return -EOPNOTSUPP;
569 }
570
571 ret = hid_hw_power(hdev, PM_HINT_FULLON);
572 if (ret < 0) {
573 hid_err(hdev, "power management error: %d\n", ret);
574 return ret;
575 }
576
577 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
578 if (ret < 0) {
579 hid_warn(hdev, "Error starting transaction: %d\n", ret);
580 goto power_normal;
581 }
582
583 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
584 ret = cp2112_xfer_status(dev);
585 if (-EBUSY == ret)
586 continue;
587 if (ret < 0)
588 goto power_normal;
589 break;
590 }
591
592 if (XFER_STATUS_RETRIES <= retries) {
593 hid_warn(hdev, "Transfer timed out, cancelling.\n");
594 buf[0] = CP2112_CANCEL_TRANSFER;
595 buf[1] = 0x01;
596
597 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
598 if (ret < 0)
599 hid_warn(hdev, "Error cancelling transaction: %d\n",
600 ret);
601
602 ret = -ETIMEDOUT;
603 goto power_normal;
604 }
605
606 for (count = 0; count < read_length;) {
607 ret = cp2112_read(dev, read_buf + count, read_length - count);
608 if (ret < 0)
609 goto power_normal;
610 if (ret == 0) {
611 hid_err(hdev, "read returned 0\n");
612 ret = -EIO;
613 goto power_normal;
614 }
615 count += ret;
616 if (count > read_length) {
617 /*
618 * The hardware returned too much data.
619 * This is mostly harmless because cp2112_read()
620 * has a limit check so didn't overrun our
621 * buffer. Nevertheless, we return an error
622 * because something is seriously wrong and
623 * it shouldn't go unnoticed.
624 */
625 hid_err(hdev, "long read: %d > %zd\n",
626 ret, read_length - count + ret);
627 ret = -EIO;
628 goto power_normal;
629 }
630 }
631
632 /* return the number of transferred messages */
633 ret = num;
634
635 power_normal:
636 hid_hw_power(hdev, PM_HINT_NORMAL);
637 hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
638 return ret;
639 }
640
cp2112_xfer(struct i2c_adapter * adap,u16 addr,unsigned short flags,char read_write,u8 command,int size,union i2c_smbus_data * data)641 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
642 unsigned short flags, char read_write, u8 command,
643 int size, union i2c_smbus_data *data)
644 {
645 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
646 struct hid_device *hdev = dev->hdev;
647 u8 buf[64];
648 __le16 word;
649 ssize_t count;
650 size_t read_length = 0;
651 unsigned int retries;
652 int ret;
653
654 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
655 read_write == I2C_SMBUS_WRITE ? "write" : "read",
656 addr, flags, command, size);
657
658 switch (size) {
659 case I2C_SMBUS_BYTE:
660 read_length = 1;
661
662 if (I2C_SMBUS_READ == read_write)
663 count = cp2112_read_req(buf, addr, read_length);
664 else
665 count = cp2112_write_req(buf, addr, command, NULL,
666 0);
667 break;
668 case I2C_SMBUS_BYTE_DATA:
669 read_length = 1;
670
671 if (I2C_SMBUS_READ == read_write)
672 count = cp2112_write_read_req(buf, addr, read_length,
673 command, NULL, 0);
674 else
675 count = cp2112_write_req(buf, addr, command,
676 &data->byte, 1);
677 break;
678 case I2C_SMBUS_WORD_DATA:
679 read_length = 2;
680 word = cpu_to_le16(data->word);
681
682 if (I2C_SMBUS_READ == read_write)
683 count = cp2112_write_read_req(buf, addr, read_length,
684 command, NULL, 0);
685 else
686 count = cp2112_write_req(buf, addr, command,
687 (u8 *)&word, 2);
688 break;
689 case I2C_SMBUS_PROC_CALL:
690 size = I2C_SMBUS_WORD_DATA;
691 read_write = I2C_SMBUS_READ;
692 read_length = 2;
693 word = cpu_to_le16(data->word);
694
695 count = cp2112_write_read_req(buf, addr, read_length, command,
696 (u8 *)&word, 2);
697 break;
698 case I2C_SMBUS_I2C_BLOCK_DATA:
699 if (read_write == I2C_SMBUS_READ) {
700 read_length = data->block[0];
701 count = cp2112_write_read_req(buf, addr, read_length,
702 command, NULL, 0);
703 } else {
704 count = cp2112_write_req(buf, addr, command,
705 data->block + 1,
706 data->block[0]);
707 }
708 break;
709 case I2C_SMBUS_BLOCK_DATA:
710 if (I2C_SMBUS_READ == read_write) {
711 count = cp2112_write_read_req(buf, addr,
712 I2C_SMBUS_BLOCK_MAX,
713 command, NULL, 0);
714 } else {
715 count = cp2112_write_req(buf, addr, command,
716 data->block,
717 data->block[0] + 1);
718 }
719 break;
720 case I2C_SMBUS_BLOCK_PROC_CALL:
721 size = I2C_SMBUS_BLOCK_DATA;
722 read_write = I2C_SMBUS_READ;
723
724 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
725 command, data->block,
726 data->block[0] + 1);
727 break;
728 default:
729 hid_warn(hdev, "Unsupported transaction %d\n", size);
730 return -EOPNOTSUPP;
731 }
732
733 if (count < 0)
734 return count;
735
736 ret = hid_hw_power(hdev, PM_HINT_FULLON);
737 if (ret < 0) {
738 hid_err(hdev, "power management error: %d\n", ret);
739 return ret;
740 }
741
742 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
743 if (ret < 0) {
744 hid_warn(hdev, "Error starting transaction: %d\n", ret);
745 goto power_normal;
746 }
747
748 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
749 ret = cp2112_xfer_status(dev);
750 if (-EBUSY == ret)
751 continue;
752 if (ret < 0)
753 goto power_normal;
754 break;
755 }
756
757 if (XFER_STATUS_RETRIES <= retries) {
758 hid_warn(hdev, "Transfer timed out, cancelling.\n");
759 buf[0] = CP2112_CANCEL_TRANSFER;
760 buf[1] = 0x01;
761
762 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
763 if (ret < 0)
764 hid_warn(hdev, "Error cancelling transaction: %d\n",
765 ret);
766
767 ret = -ETIMEDOUT;
768 goto power_normal;
769 }
770
771 if (I2C_SMBUS_WRITE == read_write) {
772 ret = 0;
773 goto power_normal;
774 }
775
776 if (I2C_SMBUS_BLOCK_DATA == size)
777 read_length = ret;
778
779 ret = cp2112_read(dev, buf, read_length);
780 if (ret < 0)
781 goto power_normal;
782 if (ret != read_length) {
783 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
784 ret = -EIO;
785 goto power_normal;
786 }
787
788 switch (size) {
789 case I2C_SMBUS_BYTE:
790 case I2C_SMBUS_BYTE_DATA:
791 data->byte = buf[0];
792 break;
793 case I2C_SMBUS_WORD_DATA:
794 data->word = le16_to_cpup((__le16 *)buf);
795 break;
796 case I2C_SMBUS_I2C_BLOCK_DATA:
797 if (read_length > I2C_SMBUS_BLOCK_MAX) {
798 ret = -EINVAL;
799 goto power_normal;
800 }
801
802 memcpy(data->block + 1, buf, read_length);
803 break;
804 case I2C_SMBUS_BLOCK_DATA:
805 if (read_length > I2C_SMBUS_BLOCK_MAX) {
806 ret = -EPROTO;
807 goto power_normal;
808 }
809
810 memcpy(data->block, buf, read_length);
811 break;
812 }
813
814 ret = 0;
815 power_normal:
816 hid_hw_power(hdev, PM_HINT_NORMAL);
817 hid_dbg(hdev, "transfer finished: %d\n", ret);
818 return ret;
819 }
820
cp2112_functionality(struct i2c_adapter * adap)821 static u32 cp2112_functionality(struct i2c_adapter *adap)
822 {
823 return I2C_FUNC_I2C |
824 I2C_FUNC_SMBUS_BYTE |
825 I2C_FUNC_SMBUS_BYTE_DATA |
826 I2C_FUNC_SMBUS_WORD_DATA |
827 I2C_FUNC_SMBUS_BLOCK_DATA |
828 I2C_FUNC_SMBUS_I2C_BLOCK |
829 I2C_FUNC_SMBUS_PROC_CALL |
830 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
831 }
832
833 static const struct i2c_algorithm smbus_algorithm = {
834 .master_xfer = cp2112_i2c_xfer,
835 .smbus_xfer = cp2112_xfer,
836 .functionality = cp2112_functionality,
837 };
838
cp2112_get_usb_config(struct hid_device * hdev,struct cp2112_usb_config_report * cfg)839 static int cp2112_get_usb_config(struct hid_device *hdev,
840 struct cp2112_usb_config_report *cfg)
841 {
842 int ret;
843
844 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
845 HID_FEATURE_REPORT);
846 if (ret != sizeof(*cfg)) {
847 hid_err(hdev, "error reading usb config: %d\n", ret);
848 if (ret < 0)
849 return ret;
850 return -EIO;
851 }
852
853 return 0;
854 }
855
cp2112_set_usb_config(struct hid_device * hdev,struct cp2112_usb_config_report * cfg)856 static int cp2112_set_usb_config(struct hid_device *hdev,
857 struct cp2112_usb_config_report *cfg)
858 {
859 int ret;
860
861 BUG_ON(cfg->report != CP2112_USB_CONFIG);
862
863 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
864 HID_FEATURE_REPORT);
865 if (ret != sizeof(*cfg)) {
866 hid_err(hdev, "error writing usb config: %d\n", ret);
867 if (ret < 0)
868 return ret;
869 return -EIO;
870 }
871
872 return 0;
873 }
874
875 static void chmod_sysfs_attrs(struct hid_device *hdev);
876
877 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
878 static ssize_t name##_store(struct device *kdev, \
879 struct device_attribute *attr, const char *buf, \
880 size_t count) \
881 { \
882 struct hid_device *hdev = to_hid_device(kdev); \
883 struct cp2112_usb_config_report cfg; \
884 int ret = cp2112_get_usb_config(hdev, &cfg); \
885 if (ret) \
886 return ret; \
887 store; \
888 ret = cp2112_set_usb_config(hdev, &cfg); \
889 if (ret) \
890 return ret; \
891 chmod_sysfs_attrs(hdev); \
892 return count; \
893 } \
894 static ssize_t name##_show(struct device *kdev, \
895 struct device_attribute *attr, char *buf) \
896 { \
897 struct hid_device *hdev = to_hid_device(kdev); \
898 struct cp2112_usb_config_report cfg; \
899 int ret = cp2112_get_usb_config(hdev, &cfg); \
900 if (ret) \
901 return ret; \
902 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
903 } \
904 static DEVICE_ATTR_RW(name);
905
906 CP2112_CONFIG_ATTR(vendor_id, ({
907 u16 vid;
908
909 if (sscanf(buf, "%hi", &vid) != 1)
910 return -EINVAL;
911
912 cfg.vid = cpu_to_le16(vid);
913 cfg.mask = 0x01;
914 }), "0x%04x\n", le16_to_cpu(cfg.vid));
915
916 CP2112_CONFIG_ATTR(product_id, ({
917 u16 pid;
918
919 if (sscanf(buf, "%hi", &pid) != 1)
920 return -EINVAL;
921
922 cfg.pid = cpu_to_le16(pid);
923 cfg.mask = 0x02;
924 }), "0x%04x\n", le16_to_cpu(cfg.pid));
925
926 CP2112_CONFIG_ATTR(max_power, ({
927 int mA;
928
929 if (sscanf(buf, "%i", &mA) != 1)
930 return -EINVAL;
931
932 cfg.max_power = (mA + 1) / 2;
933 cfg.mask = 0x04;
934 }), "%u mA\n", cfg.max_power * 2);
935
936 CP2112_CONFIG_ATTR(power_mode, ({
937 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
938 return -EINVAL;
939
940 cfg.mask = 0x08;
941 }), "%u\n", cfg.power_mode);
942
943 CP2112_CONFIG_ATTR(release_version, ({
944 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
945 != 2)
946 return -EINVAL;
947
948 cfg.mask = 0x10;
949 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
950
951 #undef CP2112_CONFIG_ATTR
952
953 struct cp2112_pstring_attribute {
954 struct device_attribute attr;
955 unsigned char report;
956 };
957
pstr_store(struct device * kdev,struct device_attribute * kattr,const char * buf,size_t count)958 static ssize_t pstr_store(struct device *kdev,
959 struct device_attribute *kattr, const char *buf,
960 size_t count)
961 {
962 struct hid_device *hdev = to_hid_device(kdev);
963 struct cp2112_pstring_attribute *attr =
964 container_of(kattr, struct cp2112_pstring_attribute, attr);
965 struct cp2112_string_report report;
966 int ret;
967
968 memset(&report, 0, sizeof(report));
969
970 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
971 report.string, ARRAY_SIZE(report.string));
972 report.report = attr->report;
973 report.length = ret * sizeof(report.string[0]) + 2;
974 report.type = USB_DT_STRING;
975
976 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
977 HID_FEATURE_REPORT);
978 if (ret != report.length + 1) {
979 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
980 ret);
981 if (ret < 0)
982 return ret;
983 return -EIO;
984 }
985
986 chmod_sysfs_attrs(hdev);
987 return count;
988 }
989
pstr_show(struct device * kdev,struct device_attribute * kattr,char * buf)990 static ssize_t pstr_show(struct device *kdev,
991 struct device_attribute *kattr, char *buf)
992 {
993 struct hid_device *hdev = to_hid_device(kdev);
994 struct cp2112_pstring_attribute *attr =
995 container_of(kattr, struct cp2112_pstring_attribute, attr);
996 struct cp2112_string_report report;
997 u8 length;
998 int ret;
999
1000 ret = cp2112_hid_get(hdev, attr->report, &report.report,
1001 sizeof(report) - 1, HID_FEATURE_REPORT);
1002 if (ret < 3) {
1003 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
1004 ret);
1005 if (ret < 0)
1006 return ret;
1007 return -EIO;
1008 }
1009
1010 if (report.length < 2) {
1011 hid_err(hdev, "invalid %s string length: %d\n",
1012 kattr->attr.name, report.length);
1013 return -EIO;
1014 }
1015
1016 length = report.length > ret - 1 ? ret - 1 : report.length;
1017 length = (length - 2) / sizeof(report.string[0]);
1018 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1019 PAGE_SIZE - 1);
1020 buf[ret++] = '\n';
1021 return ret;
1022 }
1023
1024 #define CP2112_PSTR_ATTR(name, _report) \
1025 static struct cp2112_pstring_attribute dev_attr_##name = { \
1026 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1027 .report = _report, \
1028 };
1029
1030 CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
1031 CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
1032 CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
1033
1034 #undef CP2112_PSTR_ATTR
1035
1036 static const struct attribute_group cp2112_attr_group = {
1037 .attrs = (struct attribute *[]){
1038 &dev_attr_vendor_id.attr,
1039 &dev_attr_product_id.attr,
1040 &dev_attr_max_power.attr,
1041 &dev_attr_power_mode.attr,
1042 &dev_attr_release_version.attr,
1043 &dev_attr_manufacturer.attr.attr,
1044 &dev_attr_product.attr.attr,
1045 &dev_attr_serial.attr.attr,
1046 NULL
1047 }
1048 };
1049
1050 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1051 * PROM have already been programmed. We do not depend on this preventing
1052 * writing to these attributes since the CP2112 will simply ignore writes to
1053 * already-programmed fields. This is why there is no sense in fixing this
1054 * racy behaviour.
1055 */
chmod_sysfs_attrs(struct hid_device * hdev)1056 static void chmod_sysfs_attrs(struct hid_device *hdev)
1057 {
1058 struct attribute **attr;
1059 u8 buf[2];
1060 int ret;
1061
1062 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1063 HID_FEATURE_REPORT);
1064 if (ret != sizeof(buf)) {
1065 hid_err(hdev, "error reading lock byte: %d\n", ret);
1066 return;
1067 }
1068
1069 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1070 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1071 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1072 if (ret < 0)
1073 hid_err(hdev, "error chmoding sysfs file %s\n",
1074 (*attr)->name);
1075 buf[1] >>= 1;
1076 }
1077 }
1078
cp2112_gpio_irq_ack(struct irq_data * d)1079 static void cp2112_gpio_irq_ack(struct irq_data *d)
1080 {
1081 }
1082
cp2112_gpio_irq_mask(struct irq_data * d)1083 static void cp2112_gpio_irq_mask(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
1088 __clear_bit(d->hwirq, &dev->irq_mask);
1089 }
1090
cp2112_gpio_irq_unmask(struct irq_data * d)1091 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1092 {
1093 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1094 struct cp2112_device *dev = gpiochip_get_data(gc);
1095
1096 __set_bit(d->hwirq, &dev->irq_mask);
1097 }
1098
cp2112_gpio_poll_callback(struct work_struct * work)1099 static void cp2112_gpio_poll_callback(struct work_struct *work)
1100 {
1101 struct cp2112_device *dev = container_of(work, struct cp2112_device,
1102 gpio_poll_worker.work);
1103 struct irq_data *d;
1104 u8 gpio_mask;
1105 u8 virqs = (u8)dev->irq_mask;
1106 u32 irq_type;
1107 int irq, virq, ret;
1108
1109 ret = cp2112_gpio_get_all(&dev->gc);
1110 if (ret == -ENODEV) /* the hardware has been disconnected */
1111 return;
1112 if (ret < 0)
1113 goto exit;
1114
1115 gpio_mask = ret;
1116
1117 while (virqs) {
1118 virq = ffs(virqs) - 1;
1119 virqs &= ~BIT(virq);
1120
1121 if (!dev->gc.to_irq)
1122 break;
1123
1124 irq = dev->gc.to_irq(&dev->gc, virq);
1125
1126 d = irq_get_irq_data(irq);
1127 if (!d)
1128 continue;
1129
1130 irq_type = irqd_get_trigger_type(d);
1131
1132 if (gpio_mask & BIT(virq)) {
1133 /* Level High */
1134
1135 if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1136 handle_nested_irq(irq);
1137
1138 if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1139 !(dev->gpio_prev_state & BIT(virq)))
1140 handle_nested_irq(irq);
1141 } else {
1142 /* Level Low */
1143
1144 if (irq_type & IRQ_TYPE_LEVEL_LOW)
1145 handle_nested_irq(irq);
1146
1147 if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1148 (dev->gpio_prev_state & BIT(virq)))
1149 handle_nested_irq(irq);
1150 }
1151 }
1152
1153 dev->gpio_prev_state = gpio_mask;
1154
1155 exit:
1156 if (dev->gpio_poll)
1157 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1158 }
1159
1160
cp2112_gpio_irq_startup(struct irq_data * d)1161 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1162 {
1163 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1164 struct cp2112_device *dev = gpiochip_get_data(gc);
1165
1166 INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1167
1168 if (!dev->gpio_poll) {
1169 dev->gpio_poll = true;
1170 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1171 }
1172
1173 cp2112_gpio_irq_unmask(d);
1174 return 0;
1175 }
1176
cp2112_gpio_irq_shutdown(struct irq_data * d)1177 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1178 {
1179 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1180 struct cp2112_device *dev = gpiochip_get_data(gc);
1181
1182 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1183 }
1184
cp2112_gpio_irq_type(struct irq_data * d,unsigned int type)1185 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1186 {
1187 return 0;
1188 }
1189
1190 static struct irq_chip cp2112_gpio_irqchip = {
1191 .name = "cp2112-gpio",
1192 .irq_startup = cp2112_gpio_irq_startup,
1193 .irq_shutdown = cp2112_gpio_irq_shutdown,
1194 .irq_ack = cp2112_gpio_irq_ack,
1195 .irq_mask = cp2112_gpio_irq_mask,
1196 .irq_unmask = cp2112_gpio_irq_unmask,
1197 .irq_set_type = cp2112_gpio_irq_type,
1198 };
1199
cp2112_allocate_irq(struct cp2112_device * dev,int pin)1200 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1201 int pin)
1202 {
1203 int ret;
1204
1205 if (dev->desc[pin])
1206 return -EINVAL;
1207
1208 dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1209 "HID/I2C:Event");
1210 if (IS_ERR(dev->desc[pin])) {
1211 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1212 return PTR_ERR(dev->desc[pin]);
1213 }
1214
1215 ret = cp2112_gpio_direction_input(&dev->gc, pin);
1216 if (ret < 0) {
1217 dev_err(dev->gc.parent, "Failed to set GPIO to input dir\n");
1218 goto err_desc;
1219 }
1220
1221 ret = gpiochip_lock_as_irq(&dev->gc, pin);
1222 if (ret) {
1223 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1224 goto err_desc;
1225 }
1226
1227 ret = gpiod_to_irq(dev->desc[pin]);
1228 if (ret < 0) {
1229 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1230 goto err_lock;
1231 }
1232
1233 return ret;
1234
1235 err_lock:
1236 gpiochip_unlock_as_irq(&dev->gc, pin);
1237 err_desc:
1238 gpiochip_free_own_desc(dev->desc[pin]);
1239 dev->desc[pin] = NULL;
1240 return ret;
1241 }
1242
cp2112_probe(struct hid_device * hdev,const struct hid_device_id * id)1243 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1244 {
1245 struct cp2112_device *dev;
1246 u8 buf[3];
1247 struct cp2112_smbus_config_report config;
1248 int ret;
1249
1250 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1251 if (!dev)
1252 return -ENOMEM;
1253
1254 dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1255 GFP_KERNEL);
1256 if (!dev->in_out_buffer)
1257 return -ENOMEM;
1258
1259 mutex_init(&dev->lock);
1260
1261 ret = hid_parse(hdev);
1262 if (ret) {
1263 hid_err(hdev, "parse failed\n");
1264 return ret;
1265 }
1266
1267 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1268 if (ret) {
1269 hid_err(hdev, "hw start failed\n");
1270 return ret;
1271 }
1272
1273 ret = hid_hw_open(hdev);
1274 if (ret) {
1275 hid_err(hdev, "hw open failed\n");
1276 goto err_hid_stop;
1277 }
1278
1279 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1280 if (ret < 0) {
1281 hid_err(hdev, "power management error: %d\n", ret);
1282 goto err_hid_close;
1283 }
1284
1285 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1286 HID_FEATURE_REPORT);
1287 if (ret != sizeof(buf)) {
1288 hid_err(hdev, "error requesting version\n");
1289 if (ret >= 0)
1290 ret = -EIO;
1291 goto err_power_normal;
1292 }
1293
1294 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1295 buf[1], buf[2]);
1296
1297 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1298 sizeof(config), HID_FEATURE_REPORT);
1299 if (ret != sizeof(config)) {
1300 hid_err(hdev, "error requesting SMBus config\n");
1301 if (ret >= 0)
1302 ret = -EIO;
1303 goto err_power_normal;
1304 }
1305
1306 config.retry_time = cpu_to_be16(1);
1307
1308 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1309 HID_FEATURE_REPORT);
1310 if (ret != sizeof(config)) {
1311 hid_err(hdev, "error setting SMBus config\n");
1312 if (ret >= 0)
1313 ret = -EIO;
1314 goto err_power_normal;
1315 }
1316
1317 hid_set_drvdata(hdev, (void *)dev);
1318 dev->hdev = hdev;
1319 dev->adap.owner = THIS_MODULE;
1320 dev->adap.class = I2C_CLASS_HWMON;
1321 dev->adap.algo = &smbus_algorithm;
1322 dev->adap.algo_data = dev;
1323 dev->adap.dev.parent = &hdev->dev;
1324 snprintf(dev->adap.name, sizeof(dev->adap.name),
1325 "CP2112 SMBus Bridge on hidraw%d",
1326 ((struct hidraw *)hdev->hidraw)->minor);
1327 dev->hwversion = buf[2];
1328 init_waitqueue_head(&dev->wait);
1329
1330 hid_device_io_start(hdev);
1331 ret = i2c_add_adapter(&dev->adap);
1332 hid_device_io_stop(hdev);
1333
1334 if (ret) {
1335 hid_err(hdev, "error registering i2c adapter\n");
1336 goto err_power_normal;
1337 }
1338
1339 hid_dbg(hdev, "adapter registered\n");
1340
1341 dev->gc.label = "cp2112_gpio";
1342 dev->gc.direction_input = cp2112_gpio_direction_input;
1343 dev->gc.direction_output = cp2112_gpio_direction_output;
1344 dev->gc.set = cp2112_gpio_set;
1345 dev->gc.get = cp2112_gpio_get;
1346 dev->gc.base = -1;
1347 dev->gc.ngpio = 8;
1348 dev->gc.can_sleep = 1;
1349 dev->gc.parent = &hdev->dev;
1350
1351 ret = gpiochip_add_data(&dev->gc, dev);
1352 if (ret < 0) {
1353 hid_err(hdev, "error registering gpio chip\n");
1354 goto err_free_i2c;
1355 }
1356
1357 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1358 if (ret < 0) {
1359 hid_err(hdev, "error creating sysfs attrs\n");
1360 goto err_gpiochip_remove;
1361 }
1362
1363 chmod_sysfs_attrs(hdev);
1364 hid_hw_power(hdev, PM_HINT_NORMAL);
1365
1366 ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1367 handle_simple_irq, IRQ_TYPE_NONE);
1368 if (ret) {
1369 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1370 goto err_sysfs_remove;
1371 }
1372
1373 return ret;
1374
1375 err_sysfs_remove:
1376 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1377 err_gpiochip_remove:
1378 gpiochip_remove(&dev->gc);
1379 err_free_i2c:
1380 i2c_del_adapter(&dev->adap);
1381 err_power_normal:
1382 hid_hw_power(hdev, PM_HINT_NORMAL);
1383 err_hid_close:
1384 hid_hw_close(hdev);
1385 err_hid_stop:
1386 hid_hw_stop(hdev);
1387 return ret;
1388 }
1389
cp2112_remove(struct hid_device * hdev)1390 static void cp2112_remove(struct hid_device *hdev)
1391 {
1392 struct cp2112_device *dev = hid_get_drvdata(hdev);
1393 int i;
1394
1395 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1396 i2c_del_adapter(&dev->adap);
1397
1398 if (dev->gpio_poll) {
1399 dev->gpio_poll = false;
1400 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1401 }
1402
1403 for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1404 gpiochip_unlock_as_irq(&dev->gc, i);
1405 gpiochip_free_own_desc(dev->desc[i]);
1406 }
1407
1408 gpiochip_remove(&dev->gc);
1409 /* i2c_del_adapter has finished removing all i2c devices from our
1410 * adapter. Well behaved devices should no longer call our cp2112_xfer
1411 * and should have waited for any pending calls to finish. It has also
1412 * waited for device_unregister(&adap->dev) to complete. Therefore we
1413 * can safely free our struct cp2112_device.
1414 */
1415 hid_hw_close(hdev);
1416 hid_hw_stop(hdev);
1417 }
1418
cp2112_raw_event(struct hid_device * hdev,struct hid_report * report,u8 * data,int size)1419 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1420 u8 *data, int size)
1421 {
1422 struct cp2112_device *dev = hid_get_drvdata(hdev);
1423 struct cp2112_xfer_status_report *xfer = (void *)data;
1424
1425 switch (data[0]) {
1426 case CP2112_TRANSFER_STATUS_RESPONSE:
1427 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1428 xfer->status0, xfer->status1,
1429 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1430
1431 switch (xfer->status0) {
1432 case STATUS0_IDLE:
1433 dev->xfer_status = -EAGAIN;
1434 break;
1435 case STATUS0_BUSY:
1436 dev->xfer_status = -EBUSY;
1437 break;
1438 case STATUS0_COMPLETE:
1439 dev->xfer_status = be16_to_cpu(xfer->length);
1440 break;
1441 case STATUS0_ERROR:
1442 switch (xfer->status1) {
1443 case STATUS1_TIMEOUT_NACK:
1444 case STATUS1_TIMEOUT_BUS:
1445 dev->xfer_status = -ETIMEDOUT;
1446 break;
1447 default:
1448 dev->xfer_status = -EIO;
1449 break;
1450 }
1451 break;
1452 default:
1453 dev->xfer_status = -EINVAL;
1454 break;
1455 }
1456
1457 atomic_set(&dev->xfer_avail, 1);
1458 break;
1459 case CP2112_DATA_READ_RESPONSE:
1460 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1461
1462 dev->read_length = data[2];
1463 if (dev->read_length > sizeof(dev->read_data))
1464 dev->read_length = sizeof(dev->read_data);
1465
1466 memcpy(dev->read_data, &data[3], dev->read_length);
1467 atomic_set(&dev->read_avail, 1);
1468 break;
1469 default:
1470 hid_err(hdev, "unknown report\n");
1471
1472 return 0;
1473 }
1474
1475 wake_up_interruptible(&dev->wait);
1476 return 1;
1477 }
1478
1479 static struct hid_driver cp2112_driver = {
1480 .name = "cp2112",
1481 .id_table = cp2112_devices,
1482 .probe = cp2112_probe,
1483 .remove = cp2112_remove,
1484 .raw_event = cp2112_raw_event,
1485 };
1486
1487 module_hid_driver(cp2112_driver);
1488 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1489 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1490 MODULE_LICENSE("GPL");
1491
1492