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/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 size = I2C_SMBUS_BLOCK_DATA;
700 /* fallthrough */
701 case I2C_SMBUS_BLOCK_DATA:
702 if (I2C_SMBUS_READ == read_write) {
703 count = cp2112_write_read_req(buf, addr,
704 I2C_SMBUS_BLOCK_MAX,
705 command, NULL, 0);
706 } else {
707 count = cp2112_write_req(buf, addr, command,
708 data->block,
709 data->block[0] + 1);
710 }
711 break;
712 case I2C_SMBUS_BLOCK_PROC_CALL:
713 size = I2C_SMBUS_BLOCK_DATA;
714 read_write = I2C_SMBUS_READ;
715
716 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
717 command, data->block,
718 data->block[0] + 1);
719 break;
720 default:
721 hid_warn(hdev, "Unsupported transaction %d\n", size);
722 return -EOPNOTSUPP;
723 }
724
725 if (count < 0)
726 return count;
727
728 ret = hid_hw_power(hdev, PM_HINT_FULLON);
729 if (ret < 0) {
730 hid_err(hdev, "power management error: %d\n", ret);
731 return ret;
732 }
733
734 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
735 if (ret < 0) {
736 hid_warn(hdev, "Error starting transaction: %d\n", ret);
737 goto power_normal;
738 }
739
740 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
741 ret = cp2112_xfer_status(dev);
742 if (-EBUSY == ret)
743 continue;
744 if (ret < 0)
745 goto power_normal;
746 break;
747 }
748
749 if (XFER_STATUS_RETRIES <= retries) {
750 hid_warn(hdev, "Transfer timed out, cancelling.\n");
751 buf[0] = CP2112_CANCEL_TRANSFER;
752 buf[1] = 0x01;
753
754 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
755 if (ret < 0)
756 hid_warn(hdev, "Error cancelling transaction: %d\n",
757 ret);
758
759 ret = -ETIMEDOUT;
760 goto power_normal;
761 }
762
763 if (I2C_SMBUS_WRITE == read_write) {
764 ret = 0;
765 goto power_normal;
766 }
767
768 if (I2C_SMBUS_BLOCK_DATA == size)
769 read_length = ret;
770
771 ret = cp2112_read(dev, buf, read_length);
772 if (ret < 0)
773 goto power_normal;
774 if (ret != read_length) {
775 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
776 ret = -EIO;
777 goto power_normal;
778 }
779
780 switch (size) {
781 case I2C_SMBUS_BYTE:
782 case I2C_SMBUS_BYTE_DATA:
783 data->byte = buf[0];
784 break;
785 case I2C_SMBUS_WORD_DATA:
786 data->word = le16_to_cpup((__le16 *)buf);
787 break;
788 case I2C_SMBUS_BLOCK_DATA:
789 if (read_length > I2C_SMBUS_BLOCK_MAX) {
790 ret = -EPROTO;
791 goto power_normal;
792 }
793
794 memcpy(data->block, buf, read_length);
795 break;
796 }
797
798 ret = 0;
799 power_normal:
800 hid_hw_power(hdev, PM_HINT_NORMAL);
801 hid_dbg(hdev, "transfer finished: %d\n", ret);
802 return ret;
803 }
804
cp2112_functionality(struct i2c_adapter * adap)805 static u32 cp2112_functionality(struct i2c_adapter *adap)
806 {
807 return I2C_FUNC_I2C |
808 I2C_FUNC_SMBUS_BYTE |
809 I2C_FUNC_SMBUS_BYTE_DATA |
810 I2C_FUNC_SMBUS_WORD_DATA |
811 I2C_FUNC_SMBUS_BLOCK_DATA |
812 I2C_FUNC_SMBUS_I2C_BLOCK |
813 I2C_FUNC_SMBUS_PROC_CALL |
814 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
815 }
816
817 static const struct i2c_algorithm smbus_algorithm = {
818 .master_xfer = cp2112_i2c_xfer,
819 .smbus_xfer = cp2112_xfer,
820 .functionality = cp2112_functionality,
821 };
822
cp2112_get_usb_config(struct hid_device * hdev,struct cp2112_usb_config_report * cfg)823 static int cp2112_get_usb_config(struct hid_device *hdev,
824 struct cp2112_usb_config_report *cfg)
825 {
826 int ret;
827
828 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
829 HID_FEATURE_REPORT);
830 if (ret != sizeof(*cfg)) {
831 hid_err(hdev, "error reading usb config: %d\n", ret);
832 if (ret < 0)
833 return ret;
834 return -EIO;
835 }
836
837 return 0;
838 }
839
cp2112_set_usb_config(struct hid_device * hdev,struct cp2112_usb_config_report * cfg)840 static int cp2112_set_usb_config(struct hid_device *hdev,
841 struct cp2112_usb_config_report *cfg)
842 {
843 int ret;
844
845 BUG_ON(cfg->report != CP2112_USB_CONFIG);
846
847 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
848 HID_FEATURE_REPORT);
849 if (ret != sizeof(*cfg)) {
850 hid_err(hdev, "error writing usb config: %d\n", ret);
851 if (ret < 0)
852 return ret;
853 return -EIO;
854 }
855
856 return 0;
857 }
858
859 static void chmod_sysfs_attrs(struct hid_device *hdev);
860
861 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
862 static ssize_t name##_store(struct device *kdev, \
863 struct device_attribute *attr, const char *buf, \
864 size_t count) \
865 { \
866 struct hid_device *hdev = to_hid_device(kdev); \
867 struct cp2112_usb_config_report cfg; \
868 int ret = cp2112_get_usb_config(hdev, &cfg); \
869 if (ret) \
870 return ret; \
871 store; \
872 ret = cp2112_set_usb_config(hdev, &cfg); \
873 if (ret) \
874 return ret; \
875 chmod_sysfs_attrs(hdev); \
876 return count; \
877 } \
878 static ssize_t name##_show(struct device *kdev, \
879 struct device_attribute *attr, char *buf) \
880 { \
881 struct hid_device *hdev = to_hid_device(kdev); \
882 struct cp2112_usb_config_report cfg; \
883 int ret = cp2112_get_usb_config(hdev, &cfg); \
884 if (ret) \
885 return ret; \
886 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
887 } \
888 static DEVICE_ATTR_RW(name);
889
890 CP2112_CONFIG_ATTR(vendor_id, ({
891 u16 vid;
892
893 if (sscanf(buf, "%hi", &vid) != 1)
894 return -EINVAL;
895
896 cfg.vid = cpu_to_le16(vid);
897 cfg.mask = 0x01;
898 }), "0x%04x\n", le16_to_cpu(cfg.vid));
899
900 CP2112_CONFIG_ATTR(product_id, ({
901 u16 pid;
902
903 if (sscanf(buf, "%hi", &pid) != 1)
904 return -EINVAL;
905
906 cfg.pid = cpu_to_le16(pid);
907 cfg.mask = 0x02;
908 }), "0x%04x\n", le16_to_cpu(cfg.pid));
909
910 CP2112_CONFIG_ATTR(max_power, ({
911 int mA;
912
913 if (sscanf(buf, "%i", &mA) != 1)
914 return -EINVAL;
915
916 cfg.max_power = (mA + 1) / 2;
917 cfg.mask = 0x04;
918 }), "%u mA\n", cfg.max_power * 2);
919
920 CP2112_CONFIG_ATTR(power_mode, ({
921 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
922 return -EINVAL;
923
924 cfg.mask = 0x08;
925 }), "%u\n", cfg.power_mode);
926
927 CP2112_CONFIG_ATTR(release_version, ({
928 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
929 != 2)
930 return -EINVAL;
931
932 cfg.mask = 0x10;
933 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
934
935 #undef CP2112_CONFIG_ATTR
936
937 struct cp2112_pstring_attribute {
938 struct device_attribute attr;
939 unsigned char report;
940 };
941
pstr_store(struct device * kdev,struct device_attribute * kattr,const char * buf,size_t count)942 static ssize_t pstr_store(struct device *kdev,
943 struct device_attribute *kattr, const char *buf,
944 size_t count)
945 {
946 struct hid_device *hdev = to_hid_device(kdev);
947 struct cp2112_pstring_attribute *attr =
948 container_of(kattr, struct cp2112_pstring_attribute, attr);
949 struct cp2112_string_report report;
950 int ret;
951
952 memset(&report, 0, sizeof(report));
953
954 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
955 report.string, ARRAY_SIZE(report.string));
956 report.report = attr->report;
957 report.length = ret * sizeof(report.string[0]) + 2;
958 report.type = USB_DT_STRING;
959
960 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
961 HID_FEATURE_REPORT);
962 if (ret != report.length + 1) {
963 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
964 ret);
965 if (ret < 0)
966 return ret;
967 return -EIO;
968 }
969
970 chmod_sysfs_attrs(hdev);
971 return count;
972 }
973
pstr_show(struct device * kdev,struct device_attribute * kattr,char * buf)974 static ssize_t pstr_show(struct device *kdev,
975 struct device_attribute *kattr, char *buf)
976 {
977 struct hid_device *hdev = to_hid_device(kdev);
978 struct cp2112_pstring_attribute *attr =
979 container_of(kattr, struct cp2112_pstring_attribute, attr);
980 struct cp2112_string_report report;
981 u8 length;
982 int ret;
983
984 ret = cp2112_hid_get(hdev, attr->report, &report.report,
985 sizeof(report) - 1, 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) \
1009 static struct cp2112_pstring_attribute dev_attr_##name = { \
1010 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1011 .report = _report, \
1012 };
1013
1014 CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
1015 CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
1016 CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
1017
1018 #undef CP2112_PSTR_ATTR
1019
1020 static const struct attribute_group cp2112_attr_group = {
1021 .attrs = (struct attribute *[]){
1022 &dev_attr_vendor_id.attr,
1023 &dev_attr_product_id.attr,
1024 &dev_attr_max_power.attr,
1025 &dev_attr_power_mode.attr,
1026 &dev_attr_release_version.attr,
1027 &dev_attr_manufacturer.attr.attr,
1028 &dev_attr_product.attr.attr,
1029 &dev_attr_serial.attr.attr,
1030 NULL
1031 }
1032 };
1033
1034 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1035 * PROM have already been programmed. We do not depend on this preventing
1036 * writing to these attributes since the CP2112 will simply ignore writes to
1037 * already-programmed fields. This is why there is no sense in fixing this
1038 * racy behaviour.
1039 */
chmod_sysfs_attrs(struct hid_device * hdev)1040 static void chmod_sysfs_attrs(struct hid_device *hdev)
1041 {
1042 struct attribute **attr;
1043 u8 buf[2];
1044 int ret;
1045
1046 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1047 HID_FEATURE_REPORT);
1048 if (ret != sizeof(buf)) {
1049 hid_err(hdev, "error reading lock byte: %d\n", ret);
1050 return;
1051 }
1052
1053 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1054 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1055 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1056 if (ret < 0)
1057 hid_err(hdev, "error chmoding sysfs file %s\n",
1058 (*attr)->name);
1059 buf[1] >>= 1;
1060 }
1061 }
1062
cp2112_gpio_irq_ack(struct irq_data * d)1063 static void cp2112_gpio_irq_ack(struct irq_data *d)
1064 {
1065 }
1066
cp2112_gpio_irq_mask(struct irq_data * d)1067 static void cp2112_gpio_irq_mask(struct irq_data *d)
1068 {
1069 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1070 struct cp2112_device *dev = gpiochip_get_data(gc);
1071
1072 __clear_bit(d->hwirq, &dev->irq_mask);
1073 }
1074
cp2112_gpio_irq_unmask(struct irq_data * d)1075 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1076 {
1077 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1078 struct cp2112_device *dev = gpiochip_get_data(gc);
1079
1080 __set_bit(d->hwirq, &dev->irq_mask);
1081 }
1082
cp2112_gpio_poll_callback(struct work_struct * work)1083 static void cp2112_gpio_poll_callback(struct work_struct *work)
1084 {
1085 struct cp2112_device *dev = container_of(work, struct cp2112_device,
1086 gpio_poll_worker.work);
1087 struct irq_data *d;
1088 u8 gpio_mask;
1089 u8 virqs = (u8)dev->irq_mask;
1090 u32 irq_type;
1091 int irq, virq, ret;
1092
1093 ret = cp2112_gpio_get_all(&dev->gc);
1094 if (ret == -ENODEV) /* the hardware has been disconnected */
1095 return;
1096 if (ret < 0)
1097 goto exit;
1098
1099 gpio_mask = ret;
1100
1101 while (virqs) {
1102 virq = ffs(virqs) - 1;
1103 virqs &= ~BIT(virq);
1104
1105 if (!dev->gc.to_irq)
1106 break;
1107
1108 irq = dev->gc.to_irq(&dev->gc, virq);
1109
1110 d = irq_get_irq_data(irq);
1111 if (!d)
1112 continue;
1113
1114 irq_type = irqd_get_trigger_type(d);
1115
1116 if (gpio_mask & BIT(virq)) {
1117 /* Level High */
1118
1119 if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1120 handle_nested_irq(irq);
1121
1122 if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1123 !(dev->gpio_prev_state & BIT(virq)))
1124 handle_nested_irq(irq);
1125 } else {
1126 /* Level Low */
1127
1128 if (irq_type & IRQ_TYPE_LEVEL_LOW)
1129 handle_nested_irq(irq);
1130
1131 if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1132 (dev->gpio_prev_state & BIT(virq)))
1133 handle_nested_irq(irq);
1134 }
1135 }
1136
1137 dev->gpio_prev_state = gpio_mask;
1138
1139 exit:
1140 if (dev->gpio_poll)
1141 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1142 }
1143
1144
cp2112_gpio_irq_startup(struct irq_data * d)1145 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1146 {
1147 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1148 struct cp2112_device *dev = gpiochip_get_data(gc);
1149
1150 INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1151
1152 if (!dev->gpio_poll) {
1153 dev->gpio_poll = true;
1154 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1155 }
1156
1157 cp2112_gpio_irq_unmask(d);
1158 return 0;
1159 }
1160
cp2112_gpio_irq_shutdown(struct irq_data * d)1161 static void cp2112_gpio_irq_shutdown(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 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1167 }
1168
cp2112_gpio_irq_type(struct irq_data * d,unsigned int type)1169 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1170 {
1171 return 0;
1172 }
1173
1174 static struct irq_chip cp2112_gpio_irqchip = {
1175 .name = "cp2112-gpio",
1176 .irq_startup = cp2112_gpio_irq_startup,
1177 .irq_shutdown = cp2112_gpio_irq_shutdown,
1178 .irq_ack = cp2112_gpio_irq_ack,
1179 .irq_mask = cp2112_gpio_irq_mask,
1180 .irq_unmask = cp2112_gpio_irq_unmask,
1181 .irq_set_type = cp2112_gpio_irq_type,
1182 };
1183
cp2112_allocate_irq(struct cp2112_device * dev,int pin)1184 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1185 int pin)
1186 {
1187 int ret;
1188
1189 if (dev->desc[pin])
1190 return -EINVAL;
1191
1192 dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1193 "HID/I2C:Event");
1194 if (IS_ERR(dev->desc[pin])) {
1195 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1196 return PTR_ERR(dev->desc[pin]);
1197 }
1198
1199 ret = cp2112_gpio_direction_input(&dev->gc, pin);
1200 if (ret < 0) {
1201 dev_err(dev->gc.parent, "Failed to set GPIO to input dir\n");
1202 goto err_desc;
1203 }
1204
1205 ret = gpiochip_lock_as_irq(&dev->gc, pin);
1206 if (ret) {
1207 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1208 goto err_desc;
1209 }
1210
1211 ret = gpiod_to_irq(dev->desc[pin]);
1212 if (ret < 0) {
1213 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1214 goto err_lock;
1215 }
1216
1217 return ret;
1218
1219 err_lock:
1220 gpiochip_unlock_as_irq(&dev->gc, pin);
1221 err_desc:
1222 gpiochip_free_own_desc(dev->desc[pin]);
1223 dev->desc[pin] = NULL;
1224 return ret;
1225 }
1226
cp2112_probe(struct hid_device * hdev,const struct hid_device_id * id)1227 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1228 {
1229 struct cp2112_device *dev;
1230 u8 buf[3];
1231 struct cp2112_smbus_config_report config;
1232 int ret;
1233
1234 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1235 if (!dev)
1236 return -ENOMEM;
1237
1238 dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1239 GFP_KERNEL);
1240 if (!dev->in_out_buffer)
1241 return -ENOMEM;
1242
1243 mutex_init(&dev->lock);
1244
1245 ret = hid_parse(hdev);
1246 if (ret) {
1247 hid_err(hdev, "parse failed\n");
1248 return ret;
1249 }
1250
1251 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1252 if (ret) {
1253 hid_err(hdev, "hw start failed\n");
1254 return ret;
1255 }
1256
1257 ret = hid_hw_open(hdev);
1258 if (ret) {
1259 hid_err(hdev, "hw open failed\n");
1260 goto err_hid_stop;
1261 }
1262
1263 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1264 if (ret < 0) {
1265 hid_err(hdev, "power management error: %d\n", ret);
1266 goto err_hid_close;
1267 }
1268
1269 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1270 HID_FEATURE_REPORT);
1271 if (ret != sizeof(buf)) {
1272 hid_err(hdev, "error requesting version\n");
1273 if (ret >= 0)
1274 ret = -EIO;
1275 goto err_power_normal;
1276 }
1277
1278 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1279 buf[1], buf[2]);
1280
1281 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1282 sizeof(config), HID_FEATURE_REPORT);
1283 if (ret != sizeof(config)) {
1284 hid_err(hdev, "error requesting SMBus config\n");
1285 if (ret >= 0)
1286 ret = -EIO;
1287 goto err_power_normal;
1288 }
1289
1290 config.retry_time = cpu_to_be16(1);
1291
1292 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1293 HID_FEATURE_REPORT);
1294 if (ret != sizeof(config)) {
1295 hid_err(hdev, "error setting SMBus config\n");
1296 if (ret >= 0)
1297 ret = -EIO;
1298 goto err_power_normal;
1299 }
1300
1301 hid_set_drvdata(hdev, (void *)dev);
1302 dev->hdev = hdev;
1303 dev->adap.owner = THIS_MODULE;
1304 dev->adap.class = I2C_CLASS_HWMON;
1305 dev->adap.algo = &smbus_algorithm;
1306 dev->adap.algo_data = dev;
1307 dev->adap.dev.parent = &hdev->dev;
1308 snprintf(dev->adap.name, sizeof(dev->adap.name),
1309 "CP2112 SMBus Bridge on hidraw%d",
1310 ((struct hidraw *)hdev->hidraw)->minor);
1311 dev->hwversion = buf[2];
1312 init_waitqueue_head(&dev->wait);
1313
1314 hid_device_io_start(hdev);
1315 ret = i2c_add_adapter(&dev->adap);
1316 hid_device_io_stop(hdev);
1317
1318 if (ret) {
1319 hid_err(hdev, "error registering i2c adapter\n");
1320 goto err_power_normal;
1321 }
1322
1323 hid_dbg(hdev, "adapter registered\n");
1324
1325 dev->gc.label = "cp2112_gpio";
1326 dev->gc.direction_input = cp2112_gpio_direction_input;
1327 dev->gc.direction_output = cp2112_gpio_direction_output;
1328 dev->gc.set = cp2112_gpio_set;
1329 dev->gc.get = cp2112_gpio_get;
1330 dev->gc.base = -1;
1331 dev->gc.ngpio = 8;
1332 dev->gc.can_sleep = 1;
1333 dev->gc.parent = &hdev->dev;
1334
1335 ret = gpiochip_add_data(&dev->gc, dev);
1336 if (ret < 0) {
1337 hid_err(hdev, "error registering gpio chip\n");
1338 goto err_free_i2c;
1339 }
1340
1341 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1342 if (ret < 0) {
1343 hid_err(hdev, "error creating sysfs attrs\n");
1344 goto err_gpiochip_remove;
1345 }
1346
1347 chmod_sysfs_attrs(hdev);
1348 hid_hw_power(hdev, PM_HINT_NORMAL);
1349
1350 ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1351 handle_simple_irq, IRQ_TYPE_NONE);
1352 if (ret) {
1353 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1354 goto err_sysfs_remove;
1355 }
1356
1357 return ret;
1358
1359 err_sysfs_remove:
1360 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1361 err_gpiochip_remove:
1362 gpiochip_remove(&dev->gc);
1363 err_free_i2c:
1364 i2c_del_adapter(&dev->adap);
1365 err_power_normal:
1366 hid_hw_power(hdev, PM_HINT_NORMAL);
1367 err_hid_close:
1368 hid_hw_close(hdev);
1369 err_hid_stop:
1370 hid_hw_stop(hdev);
1371 return ret;
1372 }
1373
cp2112_remove(struct hid_device * hdev)1374 static void cp2112_remove(struct hid_device *hdev)
1375 {
1376 struct cp2112_device *dev = hid_get_drvdata(hdev);
1377 int i;
1378
1379 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1380 i2c_del_adapter(&dev->adap);
1381
1382 if (dev->gpio_poll) {
1383 dev->gpio_poll = false;
1384 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1385 }
1386
1387 for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1388 gpiochip_unlock_as_irq(&dev->gc, i);
1389 gpiochip_free_own_desc(dev->desc[i]);
1390 }
1391
1392 gpiochip_remove(&dev->gc);
1393 /* i2c_del_adapter has finished removing all i2c devices from our
1394 * adapter. Well behaved devices should no longer call our cp2112_xfer
1395 * and should have waited for any pending calls to finish. It has also
1396 * waited for device_unregister(&adap->dev) to complete. Therefore we
1397 * can safely free our struct cp2112_device.
1398 */
1399 hid_hw_close(hdev);
1400 hid_hw_stop(hdev);
1401 }
1402
cp2112_raw_event(struct hid_device * hdev,struct hid_report * report,u8 * data,int size)1403 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1404 u8 *data, int size)
1405 {
1406 struct cp2112_device *dev = hid_get_drvdata(hdev);
1407 struct cp2112_xfer_status_report *xfer = (void *)data;
1408
1409 switch (data[0]) {
1410 case CP2112_TRANSFER_STATUS_RESPONSE:
1411 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1412 xfer->status0, xfer->status1,
1413 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1414
1415 switch (xfer->status0) {
1416 case STATUS0_IDLE:
1417 dev->xfer_status = -EAGAIN;
1418 break;
1419 case STATUS0_BUSY:
1420 dev->xfer_status = -EBUSY;
1421 break;
1422 case STATUS0_COMPLETE:
1423 dev->xfer_status = be16_to_cpu(xfer->length);
1424 break;
1425 case STATUS0_ERROR:
1426 switch (xfer->status1) {
1427 case STATUS1_TIMEOUT_NACK:
1428 case STATUS1_TIMEOUT_BUS:
1429 dev->xfer_status = -ETIMEDOUT;
1430 break;
1431 default:
1432 dev->xfer_status = -EIO;
1433 break;
1434 }
1435 break;
1436 default:
1437 dev->xfer_status = -EINVAL;
1438 break;
1439 }
1440
1441 atomic_set(&dev->xfer_avail, 1);
1442 break;
1443 case CP2112_DATA_READ_RESPONSE:
1444 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1445
1446 dev->read_length = data[2];
1447 if (dev->read_length > sizeof(dev->read_data))
1448 dev->read_length = sizeof(dev->read_data);
1449
1450 memcpy(dev->read_data, &data[3], dev->read_length);
1451 atomic_set(&dev->read_avail, 1);
1452 break;
1453 default:
1454 hid_err(hdev, "unknown report\n");
1455
1456 return 0;
1457 }
1458
1459 wake_up_interruptible(&dev->wait);
1460 return 1;
1461 }
1462
1463 static struct hid_driver cp2112_driver = {
1464 .name = "cp2112",
1465 .id_table = cp2112_devices,
1466 .probe = cp2112_probe,
1467 .remove = cp2112_remove,
1468 .raw_event = cp2112_raw_event,
1469 };
1470
1471 module_hid_driver(cp2112_driver);
1472 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1473 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1474 MODULE_LICENSE("GPL");
1475
1476