Merge tag 'drm-msm-fixes-2023-11-21' of https://gitlab.freedesktop.org/drm/msm into...
[linux-2.6-microblaze.git] / drivers / hid / hid-cp2112.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
4  * Copyright (c) 2013,2014 Uplogix, Inc.
5  * David Barksdale <dbarksdale@uplogix.com>
6  */
7
8 /*
9  * The Silicon Labs CP2112 chip is a USB HID device which provides an
10  * SMBus controller for talking to slave devices and 8 GPIO pins. The
11  * host communicates with the CP2112 via raw HID reports.
12  *
13  * Data Sheet:
14  *   https://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
15  * Programming Interface Specification:
16  *   https://www.silabs.com/documents/public/application-notes/an495-cp2112-interface-specification.pdf
17  */
18
19 #include <linux/bitops.h>
20 #include <linux/gpio/driver.h>
21 #include <linux/hid.h>
22 #include <linux/hidraw.h>
23 #include <linux/i2c.h>
24 #include <linux/module.h>
25 #include <linux/nls.h>
26 #include <linux/string_choices.h>
27 #include <linux/usb/ch9.h>
28 #include "hid-ids.h"
29
30 #define CP2112_REPORT_MAX_LENGTH                64
31 #define CP2112_GPIO_CONFIG_LENGTH               5
32 #define CP2112_GPIO_GET_LENGTH                  2
33 #define CP2112_GPIO_SET_LENGTH                  3
34 #define CP2112_GPIO_MAX_GPIO                    8
35 #define CP2112_GPIO_ALL_GPIO_MASK               GENMASK(7, 0)
36
37 enum {
38         CP2112_GPIO_CONFIG              = 0x02,
39         CP2112_GPIO_GET                 = 0x03,
40         CP2112_GPIO_SET                 = 0x04,
41         CP2112_GET_VERSION_INFO         = 0x05,
42         CP2112_SMBUS_CONFIG             = 0x06,
43         CP2112_DATA_READ_REQUEST        = 0x10,
44         CP2112_DATA_WRITE_READ_REQUEST  = 0x11,
45         CP2112_DATA_READ_FORCE_SEND     = 0x12,
46         CP2112_DATA_READ_RESPONSE       = 0x13,
47         CP2112_DATA_WRITE_REQUEST       = 0x14,
48         CP2112_TRANSFER_STATUS_REQUEST  = 0x15,
49         CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
50         CP2112_CANCEL_TRANSFER          = 0x17,
51         CP2112_LOCK_BYTE                = 0x20,
52         CP2112_USB_CONFIG               = 0x21,
53         CP2112_MANUFACTURER_STRING      = 0x22,
54         CP2112_PRODUCT_STRING           = 0x23,
55         CP2112_SERIAL_STRING            = 0x24,
56 };
57
58 enum {
59         STATUS0_IDLE            = 0x00,
60         STATUS0_BUSY            = 0x01,
61         STATUS0_COMPLETE        = 0x02,
62         STATUS0_ERROR           = 0x03,
63 };
64
65 enum {
66         STATUS1_TIMEOUT_NACK            = 0x00,
67         STATUS1_TIMEOUT_BUS             = 0x01,
68         STATUS1_ARBITRATION_LOST        = 0x02,
69         STATUS1_READ_INCOMPLETE         = 0x03,
70         STATUS1_WRITE_INCOMPLETE        = 0x04,
71         STATUS1_SUCCESS                 = 0x05,
72 };
73
74 struct cp2112_smbus_config_report {
75         u8 report;              /* CP2112_SMBUS_CONFIG */
76         __be32 clock_speed;     /* Hz */
77         u8 device_address;      /* Stored in the upper 7 bits */
78         u8 auto_send_read;      /* 1 = enabled, 0 = disabled */
79         __be16 write_timeout;   /* ms, 0 = no timeout */
80         __be16 read_timeout;    /* ms, 0 = no timeout */
81         u8 scl_low_timeout;     /* 1 = enabled, 0 = disabled */
82         __be16 retry_time;      /* # of retries, 0 = no limit */
83 } __packed;
84
85 struct cp2112_usb_config_report {
86         u8 report;      /* CP2112_USB_CONFIG */
87         __le16 vid;     /* Vendor ID */
88         __le16 pid;     /* Product ID */
89         u8 max_power;   /* Power requested in 2mA units */
90         u8 power_mode;  /* 0x00 = bus powered
91                            0x01 = self powered & regulator off
92                            0x02 = self powered & regulator on */
93         u8 release_major;
94         u8 release_minor;
95         u8 mask;        /* What fields to program */
96 } __packed;
97
98 struct cp2112_read_req_report {
99         u8 report;      /* CP2112_DATA_READ_REQUEST */
100         u8 slave_address;
101         __be16 length;
102 } __packed;
103
104 struct cp2112_write_read_req_report {
105         u8 report;      /* CP2112_DATA_WRITE_READ_REQUEST */
106         u8 slave_address;
107         __be16 length;
108         u8 target_address_length;
109         u8 target_address[16];
110 } __packed;
111
112 struct cp2112_write_req_report {
113         u8 report;      /* CP2112_DATA_WRITE_REQUEST */
114         u8 slave_address;
115         u8 length;
116         u8 data[61];
117 } __packed;
118
119 struct cp2112_force_read_report {
120         u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
121         __be16 length;
122 } __packed;
123
124 struct cp2112_xfer_status_report {
125         u8 report;      /* CP2112_TRANSFER_STATUS_RESPONSE */
126         u8 status0;     /* STATUS0_* */
127         u8 status1;     /* STATUS1_* */
128         __be16 retries;
129         __be16 length;
130 } __packed;
131
132 struct cp2112_string_report {
133         u8 dummy;               /* force .string to be aligned */
134         struct_group_attr(contents, __packed,
135                 u8 report;              /* CP2112_*_STRING */
136                 u8 length;              /* length in bytes of everything after .report */
137                 u8 type;                /* USB_DT_STRING */
138                 wchar_t string[30];     /* UTF16_LITTLE_ENDIAN string */
139         );
140 } __packed;
141
142 /* Number of times to request transfer status before giving up waiting for a
143    transfer to complete. This may need to be changed if SMBUS clock, retries,
144    or read/write/scl_low timeout settings are changed. */
145 static const int XFER_STATUS_RETRIES = 10;
146
147 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
148    CP2112_TRANSFER_STATUS_RESPONSE. */
149 static const int RESPONSE_TIMEOUT = 50;
150
151 static const struct hid_device_id cp2112_devices[] = {
152         { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
153         { }
154 };
155 MODULE_DEVICE_TABLE(hid, cp2112_devices);
156
157 struct cp2112_device {
158         struct i2c_adapter adap;
159         struct hid_device *hdev;
160         wait_queue_head_t wait;
161         u8 read_data[61];
162         u8 read_length;
163         u8 hwversion;
164         int xfer_status;
165         atomic_t read_avail;
166         atomic_t xfer_avail;
167         struct gpio_chip gc;
168         u8 *in_out_buffer;
169         struct mutex lock;
170
171         bool gpio_poll;
172         struct delayed_work gpio_poll_worker;
173         unsigned long irq_mask;
174         u8 gpio_prev_state;
175 };
176
177 static int gpio_push_pull = CP2112_GPIO_ALL_GPIO_MASK;
178 module_param(gpio_push_pull, int, 0644);
179 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
180
181 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
182 {
183         struct cp2112_device *dev = gpiochip_get_data(chip);
184         struct hid_device *hdev = dev->hdev;
185         u8 *buf = dev->in_out_buffer;
186         int ret;
187
188         mutex_lock(&dev->lock);
189
190         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
191                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
192                                  HID_REQ_GET_REPORT);
193         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
194                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
195                 if (ret >= 0)
196                         ret = -EIO;
197                 goto exit;
198         }
199
200         buf[1] &= ~BIT(offset);
201         buf[2] = gpio_push_pull;
202
203         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
204                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
205                                  HID_REQ_SET_REPORT);
206         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
207                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
208                 if (ret >= 0)
209                         ret = -EIO;
210                 goto exit;
211         }
212
213         ret = 0;
214
215 exit:
216         mutex_unlock(&dev->lock);
217         return ret;
218 }
219
220 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
221 {
222         struct cp2112_device *dev = gpiochip_get_data(chip);
223         struct hid_device *hdev = dev->hdev;
224         u8 *buf = dev->in_out_buffer;
225         int ret;
226
227         mutex_lock(&dev->lock);
228
229         buf[0] = CP2112_GPIO_SET;
230         buf[1] = value ? CP2112_GPIO_ALL_GPIO_MASK : 0;
231         buf[2] = BIT(offset);
232
233         ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
234                                  CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
235                                  HID_REQ_SET_REPORT);
236         if (ret < 0)
237                 hid_err(hdev, "error setting GPIO values: %d\n", ret);
238
239         mutex_unlock(&dev->lock);
240 }
241
242 static int cp2112_gpio_get_all(struct gpio_chip *chip)
243 {
244         struct cp2112_device *dev = gpiochip_get_data(chip);
245         struct hid_device *hdev = dev->hdev;
246         u8 *buf = dev->in_out_buffer;
247         int ret;
248
249         mutex_lock(&dev->lock);
250
251         ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
252                                  CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
253                                  HID_REQ_GET_REPORT);
254         if (ret != CP2112_GPIO_GET_LENGTH) {
255                 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
256                 ret = ret < 0 ? ret : -EIO;
257                 goto exit;
258         }
259
260         ret = buf[1];
261
262 exit:
263         mutex_unlock(&dev->lock);
264
265         return ret;
266 }
267
268 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
269 {
270         int ret;
271
272         ret = cp2112_gpio_get_all(chip);
273         if (ret < 0)
274                 return ret;
275
276         return (ret >> offset) & 1;
277 }
278
279 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
280                                         unsigned offset, int value)
281 {
282         struct cp2112_device *dev = gpiochip_get_data(chip);
283         struct hid_device *hdev = dev->hdev;
284         u8 *buf = dev->in_out_buffer;
285         int ret;
286
287         mutex_lock(&dev->lock);
288
289         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
290                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
291                                  HID_REQ_GET_REPORT);
292         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
293                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
294                 goto fail;
295         }
296
297         buf[1] |= 1 << offset;
298         buf[2] = gpio_push_pull;
299
300         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
301                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
302                                  HID_REQ_SET_REPORT);
303         if (ret < 0) {
304                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
305                 goto fail;
306         }
307
308         mutex_unlock(&dev->lock);
309
310         /*
311          * Set gpio value when output direction is already set,
312          * as specified in AN495, Rev. 0.2, cpt. 4.4
313          */
314         cp2112_gpio_set(chip, offset, value);
315
316         return 0;
317
318 fail:
319         mutex_unlock(&dev->lock);
320         return ret < 0 ? ret : -EIO;
321 }
322
323 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
324                           u8 *data, size_t count, unsigned char report_type)
325 {
326         u8 *buf;
327         int ret;
328
329         buf = kmalloc(count, GFP_KERNEL);
330         if (!buf)
331                 return -ENOMEM;
332
333         ret = hid_hw_raw_request(hdev, report_number, buf, count,
334                                        report_type, HID_REQ_GET_REPORT);
335         memcpy(data, buf, count);
336         kfree(buf);
337         return ret;
338 }
339
340 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
341                              unsigned char report_type)
342 {
343         u8 *buf;
344         int ret;
345
346         buf = kmemdup(data, count, GFP_KERNEL);
347         if (!buf)
348                 return -ENOMEM;
349
350         if (report_type == HID_OUTPUT_REPORT)
351                 ret = hid_hw_output_report(hdev, buf, count);
352         else
353                 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
354                                 HID_REQ_SET_REPORT);
355
356         kfree(buf);
357         return ret;
358 }
359
360 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
361 {
362         int ret = 0;
363
364         /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
365          * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
366          * come in cp2112_raw_event or timeout. There will only be one of these
367          * in flight at any one time. The timeout is extremely large and is a
368          * last resort if the CP2112 has died. If we do timeout we don't expect
369          * to receive the response which would cause data races, it's not like
370          * we can do anything about it anyway.
371          */
372         ret = wait_event_interruptible_timeout(dev->wait,
373                 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
374         if (-ERESTARTSYS == ret)
375                 return ret;
376         if (!ret)
377                 return -ETIMEDOUT;
378
379         atomic_set(avail, 0);
380         return 0;
381 }
382
383 static int cp2112_xfer_status(struct cp2112_device *dev)
384 {
385         struct hid_device *hdev = dev->hdev;
386         u8 buf[2];
387         int ret;
388
389         buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
390         buf[1] = 0x01;
391         atomic_set(&dev->xfer_avail, 0);
392
393         ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
394         if (ret < 0) {
395                 hid_warn(hdev, "Error requesting status: %d\n", ret);
396                 return ret;
397         }
398
399         ret = cp2112_wait(dev, &dev->xfer_avail);
400         if (ret)
401                 return ret;
402
403         return dev->xfer_status;
404 }
405
406 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
407 {
408         struct hid_device *hdev = dev->hdev;
409         struct cp2112_force_read_report report;
410         int ret;
411
412         if (size > sizeof(dev->read_data))
413                 size = sizeof(dev->read_data);
414         report.report = CP2112_DATA_READ_FORCE_SEND;
415         report.length = cpu_to_be16(size);
416
417         atomic_set(&dev->read_avail, 0);
418
419         ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
420                                 HID_OUTPUT_REPORT);
421         if (ret < 0) {
422                 hid_warn(hdev, "Error requesting data: %d\n", ret);
423                 return ret;
424         }
425
426         ret = cp2112_wait(dev, &dev->read_avail);
427         if (ret)
428                 return ret;
429
430         hid_dbg(hdev, "read %d of %zd bytes requested\n",
431                 dev->read_length, size);
432
433         if (size > dev->read_length)
434                 size = dev->read_length;
435
436         memcpy(data, dev->read_data, size);
437         return dev->read_length;
438 }
439
440 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
441 {
442         struct cp2112_read_req_report *report = buf;
443
444         if (length < 1 || length > 512)
445                 return -EINVAL;
446
447         report->report = CP2112_DATA_READ_REQUEST;
448         report->slave_address = slave_address << 1;
449         report->length = cpu_to_be16(length);
450         return sizeof(*report);
451 }
452
453 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
454                                  u8 command, u8 *data, u8 data_length)
455 {
456         struct cp2112_write_read_req_report *report = buf;
457
458         if (length < 1 || length > 512
459             || data_length > sizeof(report->target_address) - 1)
460                 return -EINVAL;
461
462         report->report = CP2112_DATA_WRITE_READ_REQUEST;
463         report->slave_address = slave_address << 1;
464         report->length = cpu_to_be16(length);
465         report->target_address_length = data_length + 1;
466         report->target_address[0] = command;
467         memcpy(&report->target_address[1], data, data_length);
468         return data_length + 6;
469 }
470
471 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
472                             u8 data_length)
473 {
474         struct cp2112_write_req_report *report = buf;
475
476         if (data_length > sizeof(report->data) - 1)
477                 return -EINVAL;
478
479         report->report = CP2112_DATA_WRITE_REQUEST;
480         report->slave_address = slave_address << 1;
481         report->length = data_length + 1;
482         report->data[0] = command;
483         memcpy(&report->data[1], data, data_length);
484         return data_length + 4;
485 }
486
487 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
488                                 u8 data_length)
489 {
490         struct cp2112_write_req_report *report = buf;
491
492         if (data_length > sizeof(report->data))
493                 return -EINVAL;
494
495         report->report = CP2112_DATA_WRITE_REQUEST;
496         report->slave_address = slave_address << 1;
497         report->length = data_length;
498         memcpy(report->data, data, data_length);
499         return data_length + 3;
500 }
501
502 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
503                                      u8 *addr, int addr_length,
504                                      int read_length)
505 {
506         struct cp2112_write_read_req_report *report = buf;
507
508         if (read_length < 1 || read_length > 512 ||
509             addr_length > sizeof(report->target_address))
510                 return -EINVAL;
511
512         report->report = CP2112_DATA_WRITE_READ_REQUEST;
513         report->slave_address = slave_address << 1;
514         report->length = cpu_to_be16(read_length);
515         report->target_address_length = addr_length;
516         memcpy(report->target_address, addr, addr_length);
517         return addr_length + 5;
518 }
519
520 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
521                            int num)
522 {
523         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
524         struct hid_device *hdev = dev->hdev;
525         u8 buf[64];
526         ssize_t count;
527         ssize_t read_length = 0;
528         u8 *read_buf = NULL;
529         unsigned int retries;
530         int ret;
531
532         hid_dbg(hdev, "I2C %d messages\n", num);
533
534         if (num == 1) {
535                 hid_dbg(hdev, "I2C %s %#04x len %d\n",
536                         str_read_write(msgs->flags & I2C_M_RD), msgs->addr, msgs->len);
537                 if (msgs->flags & I2C_M_RD) {
538                         read_length = msgs->len;
539                         read_buf = msgs->buf;
540                         count = cp2112_read_req(buf, msgs->addr, msgs->len);
541                 } else {
542                         count = cp2112_i2c_write_req(buf, msgs->addr,
543                                                      msgs->buf, msgs->len);
544                 }
545                 if (count < 0)
546                         return count;
547         } else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
548                    num == 2 &&
549                    msgs[0].addr == msgs[1].addr &&
550                    !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
551                 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
552                         msgs[0].addr, msgs[0].len, msgs[1].len);
553                 read_length = msgs[1].len;
554                 read_buf = msgs[1].buf;
555                 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
556                                 msgs[0].buf, msgs[0].len, msgs[1].len);
557                 if (count < 0)
558                         return count;
559         } else {
560                 hid_err(hdev,
561                         "Multi-message I2C transactions not supported\n");
562                 return -EOPNOTSUPP;
563         }
564
565         ret = hid_hw_power(hdev, PM_HINT_FULLON);
566         if (ret < 0) {
567                 hid_err(hdev, "power management error: %d\n", ret);
568                 return ret;
569         }
570
571         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
572         if (ret < 0) {
573                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
574                 goto power_normal;
575         }
576
577         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
578                 ret = cp2112_xfer_status(dev);
579                 if (-EBUSY == ret)
580                         continue;
581                 if (ret < 0)
582                         goto power_normal;
583                 break;
584         }
585
586         if (XFER_STATUS_RETRIES <= retries) {
587                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
588                 buf[0] = CP2112_CANCEL_TRANSFER;
589                 buf[1] = 0x01;
590
591                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
592                 if (ret < 0)
593                         hid_warn(hdev, "Error cancelling transaction: %d\n",
594                                  ret);
595
596                 ret = -ETIMEDOUT;
597                 goto power_normal;
598         }
599
600         for (count = 0; count < read_length;) {
601                 ret = cp2112_read(dev, read_buf + count, read_length - count);
602                 if (ret < 0)
603                         goto power_normal;
604                 if (ret == 0) {
605                         hid_err(hdev, "read returned 0\n");
606                         ret = -EIO;
607                         goto power_normal;
608                 }
609                 count += ret;
610                 if (count > read_length) {
611                         /*
612                          * The hardware returned too much data.
613                          * This is mostly harmless because cp2112_read()
614                          * has a limit check so didn't overrun our
615                          * buffer.  Nevertheless, we return an error
616                          * because something is seriously wrong and
617                          * it shouldn't go unnoticed.
618                          */
619                         hid_err(hdev, "long read: %d > %zd\n",
620                                 ret, read_length - count + ret);
621                         ret = -EIO;
622                         goto power_normal;
623                 }
624         }
625
626         /* return the number of transferred messages */
627         ret = num;
628
629 power_normal:
630         hid_hw_power(hdev, PM_HINT_NORMAL);
631         hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
632         return ret;
633 }
634
635 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
636                        unsigned short flags, char read_write, u8 command,
637                        int size, union i2c_smbus_data *data)
638 {
639         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
640         struct hid_device *hdev = dev->hdev;
641         u8 buf[64];
642         __le16 word;
643         ssize_t count;
644         size_t read_length = 0;
645         unsigned int retries;
646         int ret;
647
648         hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
649                 str_write_read(read_write == I2C_SMBUS_WRITE),
650                 addr, flags, command, size);
651
652         switch (size) {
653         case I2C_SMBUS_BYTE:
654                 read_length = 1;
655
656                 if (I2C_SMBUS_READ == read_write)
657                         count = cp2112_read_req(buf, addr, read_length);
658                 else
659                         count = cp2112_write_req(buf, addr, command, NULL,
660                                                  0);
661                 break;
662         case I2C_SMBUS_BYTE_DATA:
663                 read_length = 1;
664
665                 if (I2C_SMBUS_READ == read_write)
666                         count = cp2112_write_read_req(buf, addr, read_length,
667                                                       command, NULL, 0);
668                 else
669                         count = cp2112_write_req(buf, addr, command,
670                                                  &data->byte, 1);
671                 break;
672         case I2C_SMBUS_WORD_DATA:
673                 read_length = 2;
674                 word = cpu_to_le16(data->word);
675
676                 if (I2C_SMBUS_READ == read_write)
677                         count = cp2112_write_read_req(buf, addr, read_length,
678                                                       command, NULL, 0);
679                 else
680                         count = cp2112_write_req(buf, addr, command,
681                                                  (u8 *)&word, 2);
682                 break;
683         case I2C_SMBUS_PROC_CALL:
684                 size = I2C_SMBUS_WORD_DATA;
685                 read_write = I2C_SMBUS_READ;
686                 read_length = 2;
687                 word = cpu_to_le16(data->word);
688
689                 count = cp2112_write_read_req(buf, addr, read_length, command,
690                                               (u8 *)&word, 2);
691                 break;
692         case I2C_SMBUS_I2C_BLOCK_DATA:
693                 if (read_write == I2C_SMBUS_READ) {
694                         read_length = data->block[0];
695                         count = cp2112_write_read_req(buf, addr, read_length,
696                                                       command, NULL, 0);
697                 } else {
698                         count = cp2112_write_req(buf, addr, command,
699                                                  data->block + 1,
700                                                  data->block[0]);
701                 }
702                 break;
703         case I2C_SMBUS_BLOCK_DATA:
704                 if (I2C_SMBUS_READ == read_write) {
705                         count = cp2112_write_read_req(buf, addr,
706                                                       I2C_SMBUS_BLOCK_MAX,
707                                                       command, NULL, 0);
708                 } else {
709                         count = cp2112_write_req(buf, addr, command,
710                                                  data->block,
711                                                  data->block[0] + 1);
712                 }
713                 break;
714         case I2C_SMBUS_BLOCK_PROC_CALL:
715                 size = I2C_SMBUS_BLOCK_DATA;
716                 read_write = I2C_SMBUS_READ;
717
718                 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
719                                               command, data->block,
720                                               data->block[0] + 1);
721                 break;
722         default:
723                 hid_warn(hdev, "Unsupported transaction %d\n", size);
724                 return -EOPNOTSUPP;
725         }
726
727         if (count < 0)
728                 return count;
729
730         ret = hid_hw_power(hdev, PM_HINT_FULLON);
731         if (ret < 0) {
732                 hid_err(hdev, "power management error: %d\n", ret);
733                 return ret;
734         }
735
736         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
737         if (ret < 0) {
738                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
739                 goto power_normal;
740         }
741
742         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
743                 ret = cp2112_xfer_status(dev);
744                 if (-EBUSY == ret)
745                         continue;
746                 if (ret < 0)
747                         goto power_normal;
748                 break;
749         }
750
751         if (XFER_STATUS_RETRIES <= retries) {
752                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
753                 buf[0] = CP2112_CANCEL_TRANSFER;
754                 buf[1] = 0x01;
755
756                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
757                 if (ret < 0)
758                         hid_warn(hdev, "Error cancelling transaction: %d\n",
759                                  ret);
760
761                 ret = -ETIMEDOUT;
762                 goto power_normal;
763         }
764
765         if (I2C_SMBUS_WRITE == read_write) {
766                 ret = 0;
767                 goto power_normal;
768         }
769
770         if (I2C_SMBUS_BLOCK_DATA == size)
771                 read_length = ret;
772
773         ret = cp2112_read(dev, buf, read_length);
774         if (ret < 0)
775                 goto power_normal;
776         if (ret != read_length) {
777                 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
778                 ret = -EIO;
779                 goto power_normal;
780         }
781
782         switch (size) {
783         case I2C_SMBUS_BYTE:
784         case I2C_SMBUS_BYTE_DATA:
785                 data->byte = buf[0];
786                 break;
787         case I2C_SMBUS_WORD_DATA:
788                 data->word = le16_to_cpup((__le16 *)buf);
789                 break;
790         case I2C_SMBUS_I2C_BLOCK_DATA:
791                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
792                         ret = -EINVAL;
793                         goto power_normal;
794                 }
795
796                 memcpy(data->block + 1, buf, read_length);
797                 break;
798         case I2C_SMBUS_BLOCK_DATA:
799                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
800                         ret = -EPROTO;
801                         goto power_normal;
802                 }
803
804                 memcpy(data->block, buf, read_length);
805                 break;
806         }
807
808         ret = 0;
809 power_normal:
810         hid_hw_power(hdev, PM_HINT_NORMAL);
811         hid_dbg(hdev, "transfer finished: %d\n", ret);
812         return ret;
813 }
814
815 static u32 cp2112_functionality(struct i2c_adapter *adap)
816 {
817         return I2C_FUNC_I2C |
818                 I2C_FUNC_SMBUS_BYTE |
819                 I2C_FUNC_SMBUS_BYTE_DATA |
820                 I2C_FUNC_SMBUS_WORD_DATA |
821                 I2C_FUNC_SMBUS_BLOCK_DATA |
822                 I2C_FUNC_SMBUS_I2C_BLOCK |
823                 I2C_FUNC_SMBUS_PROC_CALL |
824                 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
825 }
826
827 static const struct i2c_algorithm smbus_algorithm = {
828         .master_xfer    = cp2112_i2c_xfer,
829         .smbus_xfer     = cp2112_xfer,
830         .functionality  = cp2112_functionality,
831 };
832
833 static int cp2112_get_usb_config(struct hid_device *hdev,
834                                  struct cp2112_usb_config_report *cfg)
835 {
836         int ret;
837
838         ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
839                              HID_FEATURE_REPORT);
840         if (ret != sizeof(*cfg)) {
841                 hid_err(hdev, "error reading usb config: %d\n", ret);
842                 if (ret < 0)
843                         return ret;
844                 return -EIO;
845         }
846
847         return 0;
848 }
849
850 static int cp2112_set_usb_config(struct hid_device *hdev,
851                                  struct cp2112_usb_config_report *cfg)
852 {
853         int ret;
854
855         BUG_ON(cfg->report != CP2112_USB_CONFIG);
856
857         ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
858                                 HID_FEATURE_REPORT);
859         if (ret != sizeof(*cfg)) {
860                 hid_err(hdev, "error writing usb config: %d\n", ret);
861                 if (ret < 0)
862                         return ret;
863                 return -EIO;
864         }
865
866         return 0;
867 }
868
869 static void chmod_sysfs_attrs(struct hid_device *hdev);
870
871 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
872 static ssize_t name##_store(struct device *kdev, \
873                             struct device_attribute *attr, const char *buf, \
874                             size_t count) \
875 { \
876         struct hid_device *hdev = to_hid_device(kdev); \
877         struct cp2112_usb_config_report cfg; \
878         int ret = cp2112_get_usb_config(hdev, &cfg); \
879         if (ret) \
880                 return ret; \
881         store; \
882         ret = cp2112_set_usb_config(hdev, &cfg); \
883         if (ret) \
884                 return ret; \
885         chmod_sysfs_attrs(hdev); \
886         return count; \
887 } \
888 static ssize_t name##_show(struct device *kdev, \
889                            struct device_attribute *attr, char *buf) \
890 { \
891         struct hid_device *hdev = to_hid_device(kdev); \
892         struct cp2112_usb_config_report cfg; \
893         int ret = cp2112_get_usb_config(hdev, &cfg); \
894         if (ret) \
895                 return ret; \
896         return sysfs_emit(buf, format, ##__VA_ARGS__); \
897 } \
898 static DEVICE_ATTR_RW(name);
899
900 CP2112_CONFIG_ATTR(vendor_id, ({
901         u16 vid;
902
903         if (sscanf(buf, "%hi", &vid) != 1)
904                 return -EINVAL;
905
906         cfg.vid = cpu_to_le16(vid);
907         cfg.mask = 0x01;
908 }), "0x%04x\n", le16_to_cpu(cfg.vid));
909
910 CP2112_CONFIG_ATTR(product_id, ({
911         u16 pid;
912
913         if (sscanf(buf, "%hi", &pid) != 1)
914                 return -EINVAL;
915
916         cfg.pid = cpu_to_le16(pid);
917         cfg.mask = 0x02;
918 }), "0x%04x\n", le16_to_cpu(cfg.pid));
919
920 CP2112_CONFIG_ATTR(max_power, ({
921         int mA;
922
923         if (sscanf(buf, "%i", &mA) != 1)
924                 return -EINVAL;
925
926         cfg.max_power = (mA + 1) / 2;
927         cfg.mask = 0x04;
928 }), "%u mA\n", cfg.max_power * 2);
929
930 CP2112_CONFIG_ATTR(power_mode, ({
931         if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
932                 return -EINVAL;
933
934         cfg.mask = 0x08;
935 }), "%u\n", cfg.power_mode);
936
937 CP2112_CONFIG_ATTR(release_version, ({
938         if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
939             != 2)
940                 return -EINVAL;
941
942         cfg.mask = 0x10;
943 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
944
945 #undef CP2112_CONFIG_ATTR
946
947 static ssize_t pstr_store(struct device *kdev, struct device_attribute *kattr,
948                           const char *buf, size_t count, int number)
949 {
950         struct hid_device *hdev = to_hid_device(kdev);
951         struct cp2112_string_report report;
952         int ret;
953
954         memset(&report, 0, sizeof(report));
955
956         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
957                               report.string, ARRAY_SIZE(report.string));
958         report.report = number;
959         report.length = ret * sizeof(report.string[0]) + 2;
960         report.type = USB_DT_STRING;
961
962         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
963                                 HID_FEATURE_REPORT);
964         if (ret != report.length + 1) {
965                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
966                         ret);
967                 if (ret < 0)
968                         return ret;
969                 return -EIO;
970         }
971
972         chmod_sysfs_attrs(hdev);
973         return count;
974 }
975
976 static ssize_t pstr_show(struct device *kdev, struct device_attribute *kattr,
977                          char *buf, int number)
978 {
979         struct hid_device *hdev = to_hid_device(kdev);
980         struct cp2112_string_report report;
981         u8 length;
982         int ret;
983
984         ret = cp2112_hid_get(hdev, number, (u8 *)&report.contents,
985                              sizeof(report.contents), HID_FEATURE_REPORT);
986         if (ret < 3) {
987                 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
988                         ret);
989                 if (ret < 0)
990                         return ret;
991                 return -EIO;
992         }
993
994         if (report.length < 2) {
995                 hid_err(hdev, "invalid %s string length: %d\n",
996                         kattr->attr.name, report.length);
997                 return -EIO;
998         }
999
1000         length = report.length > ret - 1 ? ret - 1 : report.length;
1001         length = (length - 2) / sizeof(report.string[0]);
1002         ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1003                               PAGE_SIZE - 1);
1004         buf[ret++] = '\n';
1005         return ret;
1006 }
1007
1008 #define CP2112_PSTR_ATTR(name, _report) \
1009 static ssize_t name##_store(struct device *kdev, struct device_attribute *kattr, \
1010                             const char *buf, size_t count) \
1011 { \
1012         return pstr_store(kdev, kattr, buf, count, _report); \
1013 } \
1014 static ssize_t name##_show(struct device *kdev, struct device_attribute *kattr, char *buf) \
1015 { \
1016         return pstr_show(kdev, kattr, buf, _report); \
1017 } \
1018 static DEVICE_ATTR_RW(name);
1019
1020 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1021 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1022 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1023
1024 #undef CP2112_PSTR_ATTR
1025
1026 static const struct attribute_group cp2112_attr_group = {
1027         .attrs = (struct attribute *[]){
1028                 &dev_attr_vendor_id.attr,
1029                 &dev_attr_product_id.attr,
1030                 &dev_attr_max_power.attr,
1031                 &dev_attr_power_mode.attr,
1032                 &dev_attr_release_version.attr,
1033                 &dev_attr_manufacturer.attr,
1034                 &dev_attr_product.attr,
1035                 &dev_attr_serial.attr,
1036                 NULL
1037         }
1038 };
1039
1040 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1041  * PROM have already been programmed. We do not depend on this preventing
1042  * writing to these attributes since the CP2112 will simply ignore writes to
1043  * already-programmed fields. This is why there is no sense in fixing this
1044  * racy behaviour.
1045  */
1046 static void chmod_sysfs_attrs(struct hid_device *hdev)
1047 {
1048         struct attribute **attr;
1049         u8 buf[2];
1050         int ret;
1051
1052         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1053                              HID_FEATURE_REPORT);
1054         if (ret != sizeof(buf)) {
1055                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1056                 return;
1057         }
1058
1059         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1060                 umode_t mode = (buf[1] & 1) ? 0644 : 0444;
1061                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1062                 if (ret < 0)
1063                         hid_err(hdev, "error chmoding sysfs file %s\n",
1064                                 (*attr)->name);
1065                 buf[1] >>= 1;
1066         }
1067 }
1068
1069 static void cp2112_gpio_irq_ack(struct irq_data *d)
1070 {
1071 }
1072
1073 static void cp2112_gpio_irq_mask(struct irq_data *d)
1074 {
1075         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1076         struct cp2112_device *dev = gpiochip_get_data(gc);
1077         irq_hw_number_t hwirq = irqd_to_hwirq(d);
1078
1079         __clear_bit(hwirq, &dev->irq_mask);
1080         gpiochip_disable_irq(gc, hwirq);
1081 }
1082
1083 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1084 {
1085         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1086         struct cp2112_device *dev = gpiochip_get_data(gc);
1087         irq_hw_number_t hwirq = irqd_to_hwirq(d);
1088
1089         gpiochip_enable_irq(gc, hwirq);
1090         __set_bit(hwirq, &dev->irq_mask);
1091 }
1092
1093 static void cp2112_gpio_poll_callback(struct work_struct *work)
1094 {
1095         struct cp2112_device *dev = container_of(work, struct cp2112_device,
1096                                                  gpio_poll_worker.work);
1097         struct irq_data *d;
1098         u8 gpio_mask;
1099         u32 irq_type;
1100         int irq, virq, ret;
1101
1102         ret = cp2112_gpio_get_all(&dev->gc);
1103         if (ret == -ENODEV) /* the hardware has been disconnected */
1104                 return;
1105         if (ret < 0)
1106                 goto exit;
1107
1108         gpio_mask = ret;
1109         for_each_set_bit(virq, &dev->irq_mask, CP2112_GPIO_MAX_GPIO) {
1110                 irq = irq_find_mapping(dev->gc.irq.domain, virq);
1111                 if (!irq)
1112                         continue;
1113
1114                 d = irq_get_irq_data(irq);
1115                 if (!d)
1116                         continue;
1117
1118                 irq_type = irqd_get_trigger_type(d);
1119
1120                 if (gpio_mask & BIT(virq)) {
1121                         /* Level High */
1122
1123                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1124                                 handle_nested_irq(irq);
1125
1126                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1127                             !(dev->gpio_prev_state & BIT(virq)))
1128                                 handle_nested_irq(irq);
1129                 } else {
1130                         /* Level Low */
1131
1132                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1133                                 handle_nested_irq(irq);
1134
1135                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1136                             (dev->gpio_prev_state & BIT(virq)))
1137                                 handle_nested_irq(irq);
1138                 }
1139         }
1140
1141         dev->gpio_prev_state = gpio_mask;
1142
1143 exit:
1144         if (dev->gpio_poll)
1145                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1146 }
1147
1148
1149 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1150 {
1151         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1152         struct cp2112_device *dev = gpiochip_get_data(gc);
1153
1154         if (!dev->gpio_poll) {
1155                 dev->gpio_poll = true;
1156                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1157         }
1158
1159         cp2112_gpio_irq_unmask(d);
1160         return 0;
1161 }
1162
1163 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1164 {
1165         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1166         struct cp2112_device *dev = gpiochip_get_data(gc);
1167
1168         cp2112_gpio_irq_mask(d);
1169
1170         if (!dev->irq_mask) {
1171                 dev->gpio_poll = false;
1172                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1173         }
1174 }
1175
1176 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1177 {
1178         return 0;
1179 }
1180
1181 static const struct irq_chip cp2112_gpio_irqchip = {
1182         .name = "cp2112-gpio",
1183         .irq_startup = cp2112_gpio_irq_startup,
1184         .irq_shutdown = cp2112_gpio_irq_shutdown,
1185         .irq_ack = cp2112_gpio_irq_ack,
1186         .irq_mask = cp2112_gpio_irq_mask,
1187         .irq_unmask = cp2112_gpio_irq_unmask,
1188         .irq_set_type = cp2112_gpio_irq_type,
1189         .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
1190         GPIOCHIP_IRQ_RESOURCE_HELPERS,
1191 };
1192
1193 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1194 {
1195         struct cp2112_device *dev;
1196         u8 buf[3];
1197         struct cp2112_smbus_config_report config;
1198         struct gpio_irq_chip *girq;
1199         int ret;
1200
1201         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1202         if (!dev)
1203                 return -ENOMEM;
1204
1205         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1206                                           GFP_KERNEL);
1207         if (!dev->in_out_buffer)
1208                 return -ENOMEM;
1209
1210         mutex_init(&dev->lock);
1211
1212         ret = hid_parse(hdev);
1213         if (ret) {
1214                 hid_err(hdev, "parse failed\n");
1215                 return ret;
1216         }
1217
1218         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1219         if (ret) {
1220                 hid_err(hdev, "hw start failed\n");
1221                 return ret;
1222         }
1223
1224         ret = hid_hw_open(hdev);
1225         if (ret) {
1226                 hid_err(hdev, "hw open failed\n");
1227                 goto err_hid_stop;
1228         }
1229
1230         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1231         if (ret < 0) {
1232                 hid_err(hdev, "power management error: %d\n", ret);
1233                 goto err_hid_close;
1234         }
1235
1236         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1237                              HID_FEATURE_REPORT);
1238         if (ret != sizeof(buf)) {
1239                 hid_err(hdev, "error requesting version\n");
1240                 if (ret >= 0)
1241                         ret = -EIO;
1242                 goto err_power_normal;
1243         }
1244
1245         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1246                  buf[1], buf[2]);
1247
1248         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1249                              sizeof(config), HID_FEATURE_REPORT);
1250         if (ret != sizeof(config)) {
1251                 hid_err(hdev, "error requesting SMBus config\n");
1252                 if (ret >= 0)
1253                         ret = -EIO;
1254                 goto err_power_normal;
1255         }
1256
1257         config.retry_time = cpu_to_be16(1);
1258
1259         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1260                                 HID_FEATURE_REPORT);
1261         if (ret != sizeof(config)) {
1262                 hid_err(hdev, "error setting SMBus config\n");
1263                 if (ret >= 0)
1264                         ret = -EIO;
1265                 goto err_power_normal;
1266         }
1267
1268         hid_set_drvdata(hdev, (void *)dev);
1269         dev->hdev               = hdev;
1270         dev->adap.owner         = THIS_MODULE;
1271         dev->adap.class         = I2C_CLASS_HWMON;
1272         dev->adap.algo          = &smbus_algorithm;
1273         dev->adap.algo_data     = dev;
1274         dev->adap.dev.parent    = &hdev->dev;
1275         snprintf(dev->adap.name, sizeof(dev->adap.name),
1276                  "CP2112 SMBus Bridge on hidraw%d",
1277                  ((struct hidraw *)hdev->hidraw)->minor);
1278         dev->hwversion = buf[2];
1279         init_waitqueue_head(&dev->wait);
1280
1281         hid_device_io_start(hdev);
1282         ret = i2c_add_adapter(&dev->adap);
1283         hid_device_io_stop(hdev);
1284
1285         if (ret) {
1286                 hid_err(hdev, "error registering i2c adapter\n");
1287                 goto err_power_normal;
1288         }
1289
1290         hid_dbg(hdev, "adapter registered\n");
1291
1292         dev->gc.label                   = "cp2112_gpio";
1293         dev->gc.direction_input         = cp2112_gpio_direction_input;
1294         dev->gc.direction_output        = cp2112_gpio_direction_output;
1295         dev->gc.set                     = cp2112_gpio_set;
1296         dev->gc.get                     = cp2112_gpio_get;
1297         dev->gc.base                    = -1;
1298         dev->gc.ngpio                   = CP2112_GPIO_MAX_GPIO;
1299         dev->gc.can_sleep               = 1;
1300         dev->gc.parent                  = &hdev->dev;
1301
1302         girq = &dev->gc.irq;
1303         gpio_irq_chip_set_chip(girq, &cp2112_gpio_irqchip);
1304         /* The event comes from the outside so no parent handler */
1305         girq->parent_handler = NULL;
1306         girq->num_parents = 0;
1307         girq->parents = NULL;
1308         girq->default_type = IRQ_TYPE_NONE;
1309         girq->handler = handle_simple_irq;
1310         girq->threaded = true;
1311
1312         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1313
1314         ret = gpiochip_add_data(&dev->gc, dev);
1315         if (ret < 0) {
1316                 hid_err(hdev, "error registering gpio chip\n");
1317                 goto err_free_i2c;
1318         }
1319
1320         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1321         if (ret < 0) {
1322                 hid_err(hdev, "error creating sysfs attrs\n");
1323                 goto err_gpiochip_remove;
1324         }
1325
1326         chmod_sysfs_attrs(hdev);
1327         hid_hw_power(hdev, PM_HINT_NORMAL);
1328
1329         return ret;
1330
1331 err_gpiochip_remove:
1332         gpiochip_remove(&dev->gc);
1333 err_free_i2c:
1334         i2c_del_adapter(&dev->adap);
1335 err_power_normal:
1336         hid_hw_power(hdev, PM_HINT_NORMAL);
1337 err_hid_close:
1338         hid_hw_close(hdev);
1339 err_hid_stop:
1340         hid_hw_stop(hdev);
1341         return ret;
1342 }
1343
1344 static void cp2112_remove(struct hid_device *hdev)
1345 {
1346         struct cp2112_device *dev = hid_get_drvdata(hdev);
1347
1348         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1349         i2c_del_adapter(&dev->adap);
1350
1351         if (dev->gpio_poll) {
1352                 dev->gpio_poll = false;
1353                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1354         }
1355
1356         gpiochip_remove(&dev->gc);
1357         /* i2c_del_adapter has finished removing all i2c devices from our
1358          * adapter. Well behaved devices should no longer call our cp2112_xfer
1359          * and should have waited for any pending calls to finish. It has also
1360          * waited for device_unregister(&adap->dev) to complete. Therefore we
1361          * can safely free our struct cp2112_device.
1362          */
1363         hid_hw_close(hdev);
1364         hid_hw_stop(hdev);
1365 }
1366
1367 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1368                             u8 *data, int size)
1369 {
1370         struct cp2112_device *dev = hid_get_drvdata(hdev);
1371         struct cp2112_xfer_status_report *xfer = (void *)data;
1372
1373         switch (data[0]) {
1374         case CP2112_TRANSFER_STATUS_RESPONSE:
1375                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1376                         xfer->status0, xfer->status1,
1377                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1378
1379                 switch (xfer->status0) {
1380                 case STATUS0_IDLE:
1381                         dev->xfer_status = -EAGAIN;
1382                         break;
1383                 case STATUS0_BUSY:
1384                         dev->xfer_status = -EBUSY;
1385                         break;
1386                 case STATUS0_COMPLETE:
1387                         dev->xfer_status = be16_to_cpu(xfer->length);
1388                         break;
1389                 case STATUS0_ERROR:
1390                         switch (xfer->status1) {
1391                         case STATUS1_TIMEOUT_NACK:
1392                         case STATUS1_TIMEOUT_BUS:
1393                                 dev->xfer_status = -ETIMEDOUT;
1394                                 break;
1395                         default:
1396                                 dev->xfer_status = -EIO;
1397                                 break;
1398                         }
1399                         break;
1400                 default:
1401                         dev->xfer_status = -EINVAL;
1402                         break;
1403                 }
1404
1405                 atomic_set(&dev->xfer_avail, 1);
1406                 break;
1407         case CP2112_DATA_READ_RESPONSE:
1408                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1409
1410                 dev->read_length = data[2];
1411                 if (dev->read_length > sizeof(dev->read_data))
1412                         dev->read_length = sizeof(dev->read_data);
1413
1414                 memcpy(dev->read_data, &data[3], dev->read_length);
1415                 atomic_set(&dev->read_avail, 1);
1416                 break;
1417         default:
1418                 hid_err(hdev, "unknown report\n");
1419
1420                 return 0;
1421         }
1422
1423         wake_up_interruptible(&dev->wait);
1424         return 1;
1425 }
1426
1427 static struct hid_driver cp2112_driver = {
1428         .name           = "cp2112",
1429         .id_table       = cp2112_devices,
1430         .probe          = cp2112_probe,
1431         .remove         = cp2112_remove,
1432         .raw_event      = cp2112_raw_event,
1433 };
1434
1435 module_hid_driver(cp2112_driver);
1436 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1437 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1438 MODULE_LICENSE("GPL");
1439