1 // SPDX-License-Identifier: GPL-2.0-only
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>
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.
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
19 #include <linux/gpio/consumer.h>
20 #include <linux/gpio/machine.h>
21 #include <linux/gpio/driver.h>
22 #include <linux/hid.h>
23 #include <linux/hidraw.h>
24 #include <linux/i2c.h>
25 #include <linux/module.h>
26 #include <linux/nls.h>
27 #include <linux/usb/ch9.h>
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
36 CP2112_GPIO_CONFIG = 0x02,
37 CP2112_GPIO_GET = 0x03,
38 CP2112_GPIO_SET = 0x04,
39 CP2112_GET_VERSION_INFO = 0x05,
40 CP2112_SMBUS_CONFIG = 0x06,
41 CP2112_DATA_READ_REQUEST = 0x10,
42 CP2112_DATA_WRITE_READ_REQUEST = 0x11,
43 CP2112_DATA_READ_FORCE_SEND = 0x12,
44 CP2112_DATA_READ_RESPONSE = 0x13,
45 CP2112_DATA_WRITE_REQUEST = 0x14,
46 CP2112_TRANSFER_STATUS_REQUEST = 0x15,
47 CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
48 CP2112_CANCEL_TRANSFER = 0x17,
49 CP2112_LOCK_BYTE = 0x20,
50 CP2112_USB_CONFIG = 0x21,
51 CP2112_MANUFACTURER_STRING = 0x22,
52 CP2112_PRODUCT_STRING = 0x23,
53 CP2112_SERIAL_STRING = 0x24,
59 STATUS0_COMPLETE = 0x02,
64 STATUS1_TIMEOUT_NACK = 0x00,
65 STATUS1_TIMEOUT_BUS = 0x01,
66 STATUS1_ARBITRATION_LOST = 0x02,
67 STATUS1_READ_INCOMPLETE = 0x03,
68 STATUS1_WRITE_INCOMPLETE = 0x04,
69 STATUS1_SUCCESS = 0x05,
72 struct cp2112_smbus_config_report {
73 u8 report; /* CP2112_SMBUS_CONFIG */
74 __be32 clock_speed; /* Hz */
75 u8 device_address; /* Stored in the upper 7 bits */
76 u8 auto_send_read; /* 1 = enabled, 0 = disabled */
77 __be16 write_timeout; /* ms, 0 = no timeout */
78 __be16 read_timeout; /* ms, 0 = no timeout */
79 u8 scl_low_timeout; /* 1 = enabled, 0 = disabled */
80 __be16 retry_time; /* # of retries, 0 = no limit */
83 struct cp2112_usb_config_report {
84 u8 report; /* CP2112_USB_CONFIG */
85 __le16 vid; /* Vendor ID */
86 __le16 pid; /* Product ID */
87 u8 max_power; /* Power requested in 2mA units */
88 u8 power_mode; /* 0x00 = bus powered
89 0x01 = self powered & regulator off
90 0x02 = self powered & regulator on */
93 u8 mask; /* What fields to program */
96 struct cp2112_read_req_report {
97 u8 report; /* CP2112_DATA_READ_REQUEST */
102 struct cp2112_write_read_req_report {
103 u8 report; /* CP2112_DATA_WRITE_READ_REQUEST */
106 u8 target_address_length;
107 u8 target_address[16];
110 struct cp2112_write_req_report {
111 u8 report; /* CP2112_DATA_WRITE_REQUEST */
117 struct cp2112_force_read_report {
118 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
122 struct cp2112_xfer_status_report {
123 u8 report; /* CP2112_TRANSFER_STATUS_RESPONSE */
124 u8 status0; /* STATUS0_* */
125 u8 status1; /* STATUS1_* */
130 struct cp2112_string_report {
131 u8 dummy; /* force .string to be aligned */
132 u8 report; /* CP2112_*_STRING */
133 u8 length; /* length in bytes of everyting after .report */
134 u8 type; /* USB_DT_STRING */
135 wchar_t string[30]; /* UTF16_LITTLE_ENDIAN string */
138 /* Number of times to request transfer status before giving up waiting for a
139 transfer to complete. This may need to be changed if SMBUS clock, retries,
140 or read/write/scl_low timeout settings are changed. */
141 static const int XFER_STATUS_RETRIES = 10;
143 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
144 CP2112_TRANSFER_STATUS_RESPONSE. */
145 static const int RESPONSE_TIMEOUT = 50;
147 static const struct hid_device_id cp2112_devices[] = {
148 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
151 MODULE_DEVICE_TABLE(hid, cp2112_devices);
153 struct cp2112_device {
154 struct i2c_adapter adap;
155 struct hid_device *hdev;
156 wait_queue_head_t wait;
168 struct gpio_desc *desc[8];
170 struct delayed_work gpio_poll_worker;
171 unsigned long irq_mask;
175 static int gpio_push_pull = 0xFF;
176 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
177 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
179 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
181 struct cp2112_device *dev = gpiochip_get_data(chip);
182 struct hid_device *hdev = dev->hdev;
183 u8 *buf = dev->in_out_buffer;
186 mutex_lock(&dev->lock);
188 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
189 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
191 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
192 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
198 buf[1] &= ~(1 << offset);
199 buf[2] = gpio_push_pull;
201 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
202 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
204 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
205 hid_err(hdev, "error setting GPIO config: %d\n", ret);
214 mutex_unlock(&dev->lock);
218 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
220 struct cp2112_device *dev = gpiochip_get_data(chip);
221 struct hid_device *hdev = dev->hdev;
222 u8 *buf = dev->in_out_buffer;
225 mutex_lock(&dev->lock);
227 buf[0] = CP2112_GPIO_SET;
228 buf[1] = value ? 0xff : 0;
229 buf[2] = 1 << offset;
231 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
232 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
235 hid_err(hdev, "error setting GPIO values: %d\n", ret);
237 mutex_unlock(&dev->lock);
240 static int cp2112_gpio_get_all(struct gpio_chip *chip)
242 struct cp2112_device *dev = gpiochip_get_data(chip);
243 struct hid_device *hdev = dev->hdev;
244 u8 *buf = dev->in_out_buffer;
247 mutex_lock(&dev->lock);
249 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
250 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
252 if (ret != CP2112_GPIO_GET_LENGTH) {
253 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
254 ret = ret < 0 ? ret : -EIO;
261 mutex_unlock(&dev->lock);
266 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
270 ret = cp2112_gpio_get_all(chip);
274 return (ret >> offset) & 1;
277 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
278 unsigned offset, int value)
280 struct cp2112_device *dev = gpiochip_get_data(chip);
281 struct hid_device *hdev = dev->hdev;
282 u8 *buf = dev->in_out_buffer;
285 mutex_lock(&dev->lock);
287 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
288 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
290 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
291 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
295 buf[1] |= 1 << offset;
296 buf[2] = gpio_push_pull;
298 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
299 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
302 hid_err(hdev, "error setting GPIO config: %d\n", ret);
306 mutex_unlock(&dev->lock);
309 * Set gpio value when output direction is already set,
310 * as specified in AN495, Rev. 0.2, cpt. 4.4
312 cp2112_gpio_set(chip, offset, value);
317 mutex_unlock(&dev->lock);
318 return ret < 0 ? ret : -EIO;
321 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
322 u8 *data, size_t count, unsigned char report_type)
327 buf = kmalloc(count, GFP_KERNEL);
331 ret = hid_hw_raw_request(hdev, report_number, buf, count,
332 report_type, HID_REQ_GET_REPORT);
333 memcpy(data, buf, count);
338 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
339 unsigned char report_type)
344 buf = kmemdup(data, count, GFP_KERNEL);
348 if (report_type == HID_OUTPUT_REPORT)
349 ret = hid_hw_output_report(hdev, buf, count);
351 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
358 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
362 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
363 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
364 * come in cp2112_raw_event or timeout. There will only be one of these
365 * in flight at any one time. The timeout is extremely large and is a
366 * last resort if the CP2112 has died. If we do timeout we don't expect
367 * to receive the response which would cause data races, it's not like
368 * we can do anything about it anyway.
370 ret = wait_event_interruptible_timeout(dev->wait,
371 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
372 if (-ERESTARTSYS == ret)
377 atomic_set(avail, 0);
381 static int cp2112_xfer_status(struct cp2112_device *dev)
383 struct hid_device *hdev = dev->hdev;
387 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
389 atomic_set(&dev->xfer_avail, 0);
391 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
393 hid_warn(hdev, "Error requesting status: %d\n", ret);
397 ret = cp2112_wait(dev, &dev->xfer_avail);
401 return dev->xfer_status;
404 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
406 struct hid_device *hdev = dev->hdev;
407 struct cp2112_force_read_report report;
410 if (size > sizeof(dev->read_data))
411 size = sizeof(dev->read_data);
412 report.report = CP2112_DATA_READ_FORCE_SEND;
413 report.length = cpu_to_be16(size);
415 atomic_set(&dev->read_avail, 0);
417 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
420 hid_warn(hdev, "Error requesting data: %d\n", ret);
424 ret = cp2112_wait(dev, &dev->read_avail);
428 hid_dbg(hdev, "read %d of %zd bytes requested\n",
429 dev->read_length, size);
431 if (size > dev->read_length)
432 size = dev->read_length;
434 memcpy(data, dev->read_data, size);
435 return dev->read_length;
438 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
440 struct cp2112_read_req_report *report = buf;
442 if (length < 1 || length > 512)
445 report->report = CP2112_DATA_READ_REQUEST;
446 report->slave_address = slave_address << 1;
447 report->length = cpu_to_be16(length);
448 return sizeof(*report);
451 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
452 u8 command, u8 *data, u8 data_length)
454 struct cp2112_write_read_req_report *report = buf;
456 if (length < 1 || length > 512
457 || data_length > sizeof(report->target_address) - 1)
460 report->report = CP2112_DATA_WRITE_READ_REQUEST;
461 report->slave_address = slave_address << 1;
462 report->length = cpu_to_be16(length);
463 report->target_address_length = data_length + 1;
464 report->target_address[0] = command;
465 memcpy(&report->target_address[1], data, data_length);
466 return data_length + 6;
469 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
472 struct cp2112_write_req_report *report = buf;
474 if (data_length > sizeof(report->data) - 1)
477 report->report = CP2112_DATA_WRITE_REQUEST;
478 report->slave_address = slave_address << 1;
479 report->length = data_length + 1;
480 report->data[0] = command;
481 memcpy(&report->data[1], data, data_length);
482 return data_length + 4;
485 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
488 struct cp2112_write_req_report *report = buf;
490 if (data_length > sizeof(report->data))
493 report->report = CP2112_DATA_WRITE_REQUEST;
494 report->slave_address = slave_address << 1;
495 report->length = data_length;
496 memcpy(report->data, data, data_length);
497 return data_length + 3;
500 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
501 u8 *addr, int addr_length,
504 struct cp2112_write_read_req_report *report = buf;
506 if (read_length < 1 || read_length > 512 ||
507 addr_length > sizeof(report->target_address))
510 report->report = CP2112_DATA_WRITE_READ_REQUEST;
511 report->slave_address = slave_address << 1;
512 report->length = cpu_to_be16(read_length);
513 report->target_address_length = addr_length;
514 memcpy(report->target_address, addr, addr_length);
515 return addr_length + 5;
518 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
521 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
522 struct hid_device *hdev = dev->hdev;
525 ssize_t read_length = 0;
527 unsigned int retries;
530 hid_dbg(hdev, "I2C %d messages\n", num);
533 if (msgs->flags & I2C_M_RD) {
534 hid_dbg(hdev, "I2C read %#04x len %d\n",
535 msgs->addr, msgs->len);
536 read_length = msgs->len;
537 read_buf = msgs->buf;
538 count = cp2112_read_req(buf, msgs->addr, msgs->len);
540 hid_dbg(hdev, "I2C write %#04x len %d\n",
541 msgs->addr, msgs->len);
542 count = cp2112_i2c_write_req(buf, msgs->addr,
543 msgs->buf, msgs->len);
547 } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */
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);
561 "Multi-message I2C transactions not supported\n");
565 ret = hid_hw_power(hdev, PM_HINT_FULLON);
567 hid_err(hdev, "power management error: %d\n", ret);
571 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
573 hid_warn(hdev, "Error starting transaction: %d\n", ret);
577 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
578 ret = cp2112_xfer_status(dev);
586 if (XFER_STATUS_RETRIES <= retries) {
587 hid_warn(hdev, "Transfer timed out, cancelling.\n");
588 buf[0] = CP2112_CANCEL_TRANSFER;
591 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
593 hid_warn(hdev, "Error cancelling transaction: %d\n",
600 for (count = 0; count < read_length;) {
601 ret = cp2112_read(dev, read_buf + count, read_length - count);
605 hid_err(hdev, "read returned 0\n");
610 if (count > read_length) {
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.
619 hid_err(hdev, "long read: %d > %zd\n",
620 ret, read_length - count + ret);
626 /* return the number of transferred messages */
630 hid_hw_power(hdev, PM_HINT_NORMAL);
631 hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
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)
639 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
640 struct hid_device *hdev = dev->hdev;
644 size_t read_length = 0;
645 unsigned int retries;
648 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
649 read_write == I2C_SMBUS_WRITE ? "write" : "read",
650 addr, flags, command, size);
656 if (I2C_SMBUS_READ == read_write)
657 count = cp2112_read_req(buf, addr, read_length);
659 count = cp2112_write_req(buf, addr, command, NULL,
662 case I2C_SMBUS_BYTE_DATA:
665 if (I2C_SMBUS_READ == read_write)
666 count = cp2112_write_read_req(buf, addr, read_length,
669 count = cp2112_write_req(buf, addr, command,
672 case I2C_SMBUS_WORD_DATA:
674 word = cpu_to_le16(data->word);
676 if (I2C_SMBUS_READ == read_write)
677 count = cp2112_write_read_req(buf, addr, read_length,
680 count = cp2112_write_req(buf, addr, command,
683 case I2C_SMBUS_PROC_CALL:
684 size = I2C_SMBUS_WORD_DATA;
685 read_write = I2C_SMBUS_READ;
687 word = cpu_to_le16(data->word);
689 count = cp2112_write_read_req(buf, addr, read_length, command,
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,
698 count = cp2112_write_req(buf, addr, command,
703 case I2C_SMBUS_BLOCK_DATA:
704 if (I2C_SMBUS_READ == read_write) {
705 count = cp2112_write_read_req(buf, addr,
709 count = cp2112_write_req(buf, addr, command,
714 case I2C_SMBUS_BLOCK_PROC_CALL:
715 size = I2C_SMBUS_BLOCK_DATA;
716 read_write = I2C_SMBUS_READ;
718 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
719 command, data->block,
723 hid_warn(hdev, "Unsupported transaction %d\n", size);
730 ret = hid_hw_power(hdev, PM_HINT_FULLON);
732 hid_err(hdev, "power management error: %d\n", ret);
736 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
738 hid_warn(hdev, "Error starting transaction: %d\n", ret);
742 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
743 ret = cp2112_xfer_status(dev);
751 if (XFER_STATUS_RETRIES <= retries) {
752 hid_warn(hdev, "Transfer timed out, cancelling.\n");
753 buf[0] = CP2112_CANCEL_TRANSFER;
756 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
758 hid_warn(hdev, "Error cancelling transaction: %d\n",
765 if (I2C_SMBUS_WRITE == read_write) {
770 if (I2C_SMBUS_BLOCK_DATA == size)
773 ret = cp2112_read(dev, buf, read_length);
776 if (ret != read_length) {
777 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
784 case I2C_SMBUS_BYTE_DATA:
787 case I2C_SMBUS_WORD_DATA:
788 data->word = le16_to_cpup((__le16 *)buf);
790 case I2C_SMBUS_I2C_BLOCK_DATA:
791 if (read_length > I2C_SMBUS_BLOCK_MAX) {
796 memcpy(data->block + 1, buf, read_length);
798 case I2C_SMBUS_BLOCK_DATA:
799 if (read_length > I2C_SMBUS_BLOCK_MAX) {
804 memcpy(data->block, buf, read_length);
810 hid_hw_power(hdev, PM_HINT_NORMAL);
811 hid_dbg(hdev, "transfer finished: %d\n", ret);
815 static u32 cp2112_functionality(struct i2c_adapter *adap)
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;
827 static const struct i2c_algorithm smbus_algorithm = {
828 .master_xfer = cp2112_i2c_xfer,
829 .smbus_xfer = cp2112_xfer,
830 .functionality = cp2112_functionality,
833 static int cp2112_get_usb_config(struct hid_device *hdev,
834 struct cp2112_usb_config_report *cfg)
838 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
840 if (ret != sizeof(*cfg)) {
841 hid_err(hdev, "error reading usb config: %d\n", ret);
850 static int cp2112_set_usb_config(struct hid_device *hdev,
851 struct cp2112_usb_config_report *cfg)
855 BUG_ON(cfg->report != CP2112_USB_CONFIG);
857 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
859 if (ret != sizeof(*cfg)) {
860 hid_err(hdev, "error writing usb config: %d\n", ret);
869 static void chmod_sysfs_attrs(struct hid_device *hdev);
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, \
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); \
882 ret = cp2112_set_usb_config(hdev, &cfg); \
885 chmod_sysfs_attrs(hdev); \
888 static ssize_t name##_show(struct device *kdev, \
889 struct device_attribute *attr, char *buf) \
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); \
896 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
898 static DEVICE_ATTR_RW(name);
900 CP2112_CONFIG_ATTR(vendor_id, ({
903 if (sscanf(buf, "%hi", &vid) != 1)
906 cfg.vid = cpu_to_le16(vid);
908 }), "0x%04x\n", le16_to_cpu(cfg.vid));
910 CP2112_CONFIG_ATTR(product_id, ({
913 if (sscanf(buf, "%hi", &pid) != 1)
916 cfg.pid = cpu_to_le16(pid);
918 }), "0x%04x\n", le16_to_cpu(cfg.pid));
920 CP2112_CONFIG_ATTR(max_power, ({
923 if (sscanf(buf, "%i", &mA) != 1)
926 cfg.max_power = (mA + 1) / 2;
928 }), "%u mA\n", cfg.max_power * 2);
930 CP2112_CONFIG_ATTR(power_mode, ({
931 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
935 }), "%u\n", cfg.power_mode);
937 CP2112_CONFIG_ATTR(release_version, ({
938 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
943 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
945 #undef CP2112_CONFIG_ATTR
947 struct cp2112_pstring_attribute {
948 struct device_attribute attr;
949 unsigned char report;
952 static ssize_t pstr_store(struct device *kdev,
953 struct device_attribute *kattr, const char *buf,
956 struct hid_device *hdev = to_hid_device(kdev);
957 struct cp2112_pstring_attribute *attr =
958 container_of(kattr, struct cp2112_pstring_attribute, attr);
959 struct cp2112_string_report report;
962 memset(&report, 0, sizeof(report));
964 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
965 report.string, ARRAY_SIZE(report.string));
966 report.report = attr->report;
967 report.length = ret * sizeof(report.string[0]) + 2;
968 report.type = USB_DT_STRING;
970 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
972 if (ret != report.length + 1) {
973 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
980 chmod_sysfs_attrs(hdev);
984 static ssize_t pstr_show(struct device *kdev,
985 struct device_attribute *kattr, char *buf)
987 struct hid_device *hdev = to_hid_device(kdev);
988 struct cp2112_pstring_attribute *attr =
989 container_of(kattr, struct cp2112_pstring_attribute, attr);
990 struct cp2112_string_report report;
994 ret = cp2112_hid_get(hdev, attr->report, &report.report,
995 sizeof(report) - 1, HID_FEATURE_REPORT);
997 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
1004 if (report.length < 2) {
1005 hid_err(hdev, "invalid %s string length: %d\n",
1006 kattr->attr.name, report.length);
1010 length = report.length > ret - 1 ? ret - 1 : report.length;
1011 length = (length - 2) / sizeof(report.string[0]);
1012 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1018 #define CP2112_PSTR_ATTR(name, _report) \
1019 static struct cp2112_pstring_attribute dev_attr_##name = { \
1020 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1021 .report = _report, \
1024 CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
1025 CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
1026 CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
1028 #undef CP2112_PSTR_ATTR
1030 static const struct attribute_group cp2112_attr_group = {
1031 .attrs = (struct attribute *[]){
1032 &dev_attr_vendor_id.attr,
1033 &dev_attr_product_id.attr,
1034 &dev_attr_max_power.attr,
1035 &dev_attr_power_mode.attr,
1036 &dev_attr_release_version.attr,
1037 &dev_attr_manufacturer.attr.attr,
1038 &dev_attr_product.attr.attr,
1039 &dev_attr_serial.attr.attr,
1044 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1045 * PROM have already been programmed. We do not depend on this preventing
1046 * writing to these attributes since the CP2112 will simply ignore writes to
1047 * already-programmed fields. This is why there is no sense in fixing this
1050 static void chmod_sysfs_attrs(struct hid_device *hdev)
1052 struct attribute **attr;
1056 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1057 HID_FEATURE_REPORT);
1058 if (ret != sizeof(buf)) {
1059 hid_err(hdev, "error reading lock byte: %d\n", ret);
1063 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1064 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1065 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1067 hid_err(hdev, "error chmoding sysfs file %s\n",
1073 static void cp2112_gpio_irq_ack(struct irq_data *d)
1077 static void cp2112_gpio_irq_mask(struct irq_data *d)
1079 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1080 struct cp2112_device *dev = gpiochip_get_data(gc);
1082 __clear_bit(d->hwirq, &dev->irq_mask);
1085 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1087 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1088 struct cp2112_device *dev = gpiochip_get_data(gc);
1090 __set_bit(d->hwirq, &dev->irq_mask);
1093 static void cp2112_gpio_poll_callback(struct work_struct *work)
1095 struct cp2112_device *dev = container_of(work, struct cp2112_device,
1096 gpio_poll_worker.work);
1099 u8 virqs = (u8)dev->irq_mask;
1103 ret = cp2112_gpio_get_all(&dev->gc);
1104 if (ret == -ENODEV) /* the hardware has been disconnected */
1112 virq = ffs(virqs) - 1;
1113 virqs &= ~BIT(virq);
1115 if (!dev->gc.to_irq)
1118 irq = dev->gc.to_irq(&dev->gc, virq);
1120 d = irq_get_irq_data(irq);
1124 irq_type = irqd_get_trigger_type(d);
1126 if (gpio_mask & BIT(virq)) {
1129 if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1130 handle_nested_irq(irq);
1132 if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1133 !(dev->gpio_prev_state & BIT(virq)))
1134 handle_nested_irq(irq);
1138 if (irq_type & IRQ_TYPE_LEVEL_LOW)
1139 handle_nested_irq(irq);
1141 if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1142 (dev->gpio_prev_state & BIT(virq)))
1143 handle_nested_irq(irq);
1147 dev->gpio_prev_state = gpio_mask;
1151 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1155 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1157 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1158 struct cp2112_device *dev = gpiochip_get_data(gc);
1160 INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1162 if (!dev->gpio_poll) {
1163 dev->gpio_poll = true;
1164 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1167 cp2112_gpio_irq_unmask(d);
1171 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1173 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1174 struct cp2112_device *dev = gpiochip_get_data(gc);
1176 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1179 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1184 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1192 dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1196 if (IS_ERR(dev->desc[pin])) {
1197 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1198 return PTR_ERR(dev->desc[pin]);
1201 ret = cp2112_gpio_direction_input(&dev->gc, pin);
1203 dev_err(dev->gc.parent, "Failed to set GPIO to input dir\n");
1207 ret = gpiochip_lock_as_irq(&dev->gc, pin);
1209 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1213 ret = gpiod_to_irq(dev->desc[pin]);
1215 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1222 gpiochip_unlock_as_irq(&dev->gc, pin);
1224 gpiochip_free_own_desc(dev->desc[pin]);
1225 dev->desc[pin] = NULL;
1229 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1231 struct cp2112_device *dev;
1233 struct cp2112_smbus_config_report config;
1234 struct gpio_irq_chip *girq;
1237 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1241 dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1243 if (!dev->in_out_buffer)
1246 mutex_init(&dev->lock);
1248 ret = hid_parse(hdev);
1250 hid_err(hdev, "parse failed\n");
1254 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1256 hid_err(hdev, "hw start failed\n");
1260 ret = hid_hw_open(hdev);
1262 hid_err(hdev, "hw open failed\n");
1266 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1268 hid_err(hdev, "power management error: %d\n", ret);
1272 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1273 HID_FEATURE_REPORT);
1274 if (ret != sizeof(buf)) {
1275 hid_err(hdev, "error requesting version\n");
1278 goto err_power_normal;
1281 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1284 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1285 sizeof(config), HID_FEATURE_REPORT);
1286 if (ret != sizeof(config)) {
1287 hid_err(hdev, "error requesting SMBus config\n");
1290 goto err_power_normal;
1293 config.retry_time = cpu_to_be16(1);
1295 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1296 HID_FEATURE_REPORT);
1297 if (ret != sizeof(config)) {
1298 hid_err(hdev, "error setting SMBus config\n");
1301 goto err_power_normal;
1304 hid_set_drvdata(hdev, (void *)dev);
1306 dev->adap.owner = THIS_MODULE;
1307 dev->adap.class = I2C_CLASS_HWMON;
1308 dev->adap.algo = &smbus_algorithm;
1309 dev->adap.algo_data = dev;
1310 dev->adap.dev.parent = &hdev->dev;
1311 snprintf(dev->adap.name, sizeof(dev->adap.name),
1312 "CP2112 SMBus Bridge on hidraw%d",
1313 ((struct hidraw *)hdev->hidraw)->minor);
1314 dev->hwversion = buf[2];
1315 init_waitqueue_head(&dev->wait);
1317 hid_device_io_start(hdev);
1318 ret = i2c_add_adapter(&dev->adap);
1319 hid_device_io_stop(hdev);
1322 hid_err(hdev, "error registering i2c adapter\n");
1323 goto err_power_normal;
1326 hid_dbg(hdev, "adapter registered\n");
1328 dev->gc.label = "cp2112_gpio";
1329 dev->gc.direction_input = cp2112_gpio_direction_input;
1330 dev->gc.direction_output = cp2112_gpio_direction_output;
1331 dev->gc.set = cp2112_gpio_set;
1332 dev->gc.get = cp2112_gpio_get;
1335 dev->gc.can_sleep = 1;
1336 dev->gc.parent = &hdev->dev;
1338 dev->irq.name = "cp2112-gpio";
1339 dev->irq.irq_startup = cp2112_gpio_irq_startup;
1340 dev->irq.irq_shutdown = cp2112_gpio_irq_shutdown;
1341 dev->irq.irq_ack = cp2112_gpio_irq_ack;
1342 dev->irq.irq_mask = cp2112_gpio_irq_mask;
1343 dev->irq.irq_unmask = cp2112_gpio_irq_unmask;
1344 dev->irq.irq_set_type = cp2112_gpio_irq_type;
1345 dev->irq.flags = IRQCHIP_MASK_ON_SUSPEND;
1347 girq = &dev->gc.irq;
1348 girq->chip = &dev->irq;
1349 /* The event comes from the outside so no parent handler */
1350 girq->parent_handler = NULL;
1351 girq->num_parents = 0;
1352 girq->parents = NULL;
1353 girq->default_type = IRQ_TYPE_NONE;
1354 girq->handler = handle_simple_irq;
1356 ret = gpiochip_add_data(&dev->gc, dev);
1358 hid_err(hdev, "error registering gpio chip\n");
1362 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1364 hid_err(hdev, "error creating sysfs attrs\n");
1365 goto err_gpiochip_remove;
1368 chmod_sysfs_attrs(hdev);
1369 hid_hw_power(hdev, PM_HINT_NORMAL);
1373 err_gpiochip_remove:
1374 gpiochip_remove(&dev->gc);
1376 i2c_del_adapter(&dev->adap);
1378 hid_hw_power(hdev, PM_HINT_NORMAL);
1386 static void cp2112_remove(struct hid_device *hdev)
1388 struct cp2112_device *dev = hid_get_drvdata(hdev);
1391 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1392 i2c_del_adapter(&dev->adap);
1394 if (dev->gpio_poll) {
1395 dev->gpio_poll = false;
1396 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1399 for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1400 gpiochip_unlock_as_irq(&dev->gc, i);
1401 gpiochip_free_own_desc(dev->desc[i]);
1404 gpiochip_remove(&dev->gc);
1405 /* i2c_del_adapter has finished removing all i2c devices from our
1406 * adapter. Well behaved devices should no longer call our cp2112_xfer
1407 * and should have waited for any pending calls to finish. It has also
1408 * waited for device_unregister(&adap->dev) to complete. Therefore we
1409 * can safely free our struct cp2112_device.
1415 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1418 struct cp2112_device *dev = hid_get_drvdata(hdev);
1419 struct cp2112_xfer_status_report *xfer = (void *)data;
1422 case CP2112_TRANSFER_STATUS_RESPONSE:
1423 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1424 xfer->status0, xfer->status1,
1425 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1427 switch (xfer->status0) {
1429 dev->xfer_status = -EAGAIN;
1432 dev->xfer_status = -EBUSY;
1434 case STATUS0_COMPLETE:
1435 dev->xfer_status = be16_to_cpu(xfer->length);
1438 switch (xfer->status1) {
1439 case STATUS1_TIMEOUT_NACK:
1440 case STATUS1_TIMEOUT_BUS:
1441 dev->xfer_status = -ETIMEDOUT;
1444 dev->xfer_status = -EIO;
1449 dev->xfer_status = -EINVAL;
1453 atomic_set(&dev->xfer_avail, 1);
1455 case CP2112_DATA_READ_RESPONSE:
1456 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1458 dev->read_length = data[2];
1459 if (dev->read_length > sizeof(dev->read_data))
1460 dev->read_length = sizeof(dev->read_data);
1462 memcpy(dev->read_data, &data[3], dev->read_length);
1463 atomic_set(&dev->read_avail, 1);
1466 hid_err(hdev, "unknown report\n");
1471 wake_up_interruptible(&dev->wait);
1475 static struct hid_driver cp2112_driver = {
1477 .id_table = cp2112_devices,
1478 .probe = cp2112_probe,
1479 .remove = cp2112_remove,
1480 .raw_event = cp2112_raw_event,
1483 module_hid_driver(cp2112_driver);
1484 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1485 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1486 MODULE_LICENSE("GPL");