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>
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.
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
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.
22 * http://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
23 * Programming Interface Specification:
24 * http://www.silabs.com/Support%20Documents/TechnicalDocs/AN495.pdf
27 #include <linux/gpio.h>
28 #include <linux/gpio/driver.h>
29 #include <linux/hid.h>
30 #include <linux/i2c.h>
31 #include <linux/module.h>
32 #include <linux/nls.h>
33 #include <linux/usb/ch9.h>
36 #define CP2112_REPORT_MAX_LENGTH 64
37 #define CP2112_GPIO_CONFIG_LENGTH 5
38 #define CP2112_GPIO_GET_LENGTH 2
39 #define CP2112_GPIO_SET_LENGTH 3
42 CP2112_GPIO_CONFIG = 0x02,
43 CP2112_GPIO_GET = 0x03,
44 CP2112_GPIO_SET = 0x04,
45 CP2112_GET_VERSION_INFO = 0x05,
46 CP2112_SMBUS_CONFIG = 0x06,
47 CP2112_DATA_READ_REQUEST = 0x10,
48 CP2112_DATA_WRITE_READ_REQUEST = 0x11,
49 CP2112_DATA_READ_FORCE_SEND = 0x12,
50 CP2112_DATA_READ_RESPONSE = 0x13,
51 CP2112_DATA_WRITE_REQUEST = 0x14,
52 CP2112_TRANSFER_STATUS_REQUEST = 0x15,
53 CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
54 CP2112_CANCEL_TRANSFER = 0x17,
55 CP2112_LOCK_BYTE = 0x20,
56 CP2112_USB_CONFIG = 0x21,
57 CP2112_MANUFACTURER_STRING = 0x22,
58 CP2112_PRODUCT_STRING = 0x23,
59 CP2112_SERIAL_STRING = 0x24,
65 STATUS0_COMPLETE = 0x02,
70 STATUS1_TIMEOUT_NACK = 0x00,
71 STATUS1_TIMEOUT_BUS = 0x01,
72 STATUS1_ARBITRATION_LOST = 0x02,
73 STATUS1_READ_INCOMPLETE = 0x03,
74 STATUS1_WRITE_INCOMPLETE = 0x04,
75 STATUS1_SUCCESS = 0x05,
78 struct cp2112_smbus_config_report {
79 u8 report; /* CP2112_SMBUS_CONFIG */
80 __be32 clock_speed; /* Hz */
81 u8 device_address; /* Stored in the upper 7 bits */
82 u8 auto_send_read; /* 1 = enabled, 0 = disabled */
83 __be16 write_timeout; /* ms, 0 = no timeout */
84 __be16 read_timeout; /* ms, 0 = no timeout */
85 u8 scl_low_timeout; /* 1 = enabled, 0 = disabled */
86 __be16 retry_time; /* # of retries, 0 = no limit */
89 struct cp2112_usb_config_report {
90 u8 report; /* CP2112_USB_CONFIG */
91 __le16 vid; /* Vendor ID */
92 __le16 pid; /* Product ID */
93 u8 max_power; /* Power requested in 2mA units */
94 u8 power_mode; /* 0x00 = bus powered
95 0x01 = self powered & regulator off
96 0x02 = self powered & regulator on */
99 u8 mask; /* What fields to program */
102 struct cp2112_read_req_report {
103 u8 report; /* CP2112_DATA_READ_REQUEST */
108 struct cp2112_write_read_req_report {
109 u8 report; /* CP2112_DATA_WRITE_READ_REQUEST */
112 u8 target_address_length;
113 u8 target_address[16];
116 struct cp2112_write_req_report {
117 u8 report; /* CP2112_DATA_WRITE_REQUEST */
123 struct cp2112_force_read_report {
124 u8 report; /* CP2112_DATA_READ_FORCE_SEND */
128 struct cp2112_xfer_status_report {
129 u8 report; /* CP2112_TRANSFER_STATUS_RESPONSE */
130 u8 status0; /* STATUS0_* */
131 u8 status1; /* STATUS1_* */
136 struct cp2112_string_report {
137 u8 dummy; /* force .string to be aligned */
138 u8 report; /* CP2112_*_STRING */
139 u8 length; /* length in bytes of everyting after .report */
140 u8 type; /* USB_DT_STRING */
141 wchar_t string[30]; /* UTF16_LITTLE_ENDIAN string */
144 /* Number of times to request transfer status before giving up waiting for a
145 transfer to complete. This may need to be changed if SMBUS clock, retries,
146 or read/write/scl_low timeout settings are changed. */
147 static const int XFER_STATUS_RETRIES = 10;
149 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
150 CP2112_TRANSFER_STATUS_RESPONSE. */
151 static const int RESPONSE_TIMEOUT = 50;
153 static const struct hid_device_id cp2112_devices[] = {
154 { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
157 MODULE_DEVICE_TABLE(hid, cp2112_devices);
159 struct cp2112_device {
160 struct i2c_adapter adap;
161 struct hid_device *hdev;
162 wait_queue_head_t wait;
173 struct gpio_desc *desc[8];
175 struct delayed_work gpio_poll_worker;
176 unsigned long irq_mask;
180 static int gpio_push_pull = 0xFF;
181 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
182 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
184 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
186 struct cp2112_device *dev = gpiochip_get_data(chip);
187 struct hid_device *hdev = dev->hdev;
188 u8 *buf = dev->in_out_buffer;
191 mutex_lock(&dev->lock);
193 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
194 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
196 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
197 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
201 buf[1] &= ~(1 << offset);
202 buf[2] = gpio_push_pull;
204 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
205 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
208 hid_err(hdev, "error setting GPIO config: %d\n", ret);
215 mutex_unlock(&dev->lock);
216 return ret < 0 ? ret : -EIO;
219 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
221 struct cp2112_device *dev = gpiochip_get_data(chip);
222 struct hid_device *hdev = dev->hdev;
223 u8 *buf = dev->in_out_buffer;
226 mutex_lock(&dev->lock);
228 buf[0] = CP2112_GPIO_SET;
229 buf[1] = value ? 0xff : 0;
230 buf[2] = 1 << offset;
232 ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
233 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
236 hid_err(hdev, "error setting GPIO values: %d\n", ret);
238 mutex_unlock(&dev->lock);
241 static int cp2112_gpio_get_all(struct gpio_chip *chip)
243 struct cp2112_device *dev = gpiochip_get_data(chip);
244 struct hid_device *hdev = dev->hdev;
245 u8 *buf = dev->in_out_buffer;
248 mutex_lock(&dev->lock);
250 ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
251 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
253 if (ret != CP2112_GPIO_GET_LENGTH) {
254 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
255 ret = ret < 0 ? ret : -EIO;
262 mutex_unlock(&dev->lock);
267 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
271 ret = cp2112_gpio_get_all(chip);
275 return (ret >> offset) & 1;
278 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
279 unsigned offset, int value)
281 struct cp2112_device *dev = gpiochip_get_data(chip);
282 struct hid_device *hdev = dev->hdev;
283 u8 *buf = dev->in_out_buffer;
286 mutex_lock(&dev->lock);
288 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
289 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
291 if (ret != CP2112_GPIO_CONFIG_LENGTH) {
292 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
296 buf[1] |= 1 << offset;
297 buf[2] = gpio_push_pull;
299 ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
300 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
303 hid_err(hdev, "error setting GPIO config: %d\n", ret);
307 mutex_unlock(&dev->lock);
310 * Set gpio value when output direction is already set,
311 * as specified in AN495, Rev. 0.2, cpt. 4.4
313 cp2112_gpio_set(chip, offset, value);
318 mutex_unlock(&dev->lock);
319 return ret < 0 ? ret : -EIO;
322 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
323 u8 *data, size_t count, unsigned char report_type)
328 buf = kmalloc(count, GFP_KERNEL);
332 ret = hid_hw_raw_request(hdev, report_number, buf, count,
333 report_type, HID_REQ_GET_REPORT);
334 memcpy(data, buf, count);
339 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
340 unsigned char report_type)
345 buf = kmemdup(data, count, GFP_KERNEL);
349 if (report_type == HID_OUTPUT_REPORT)
350 ret = hid_hw_output_report(hdev, buf, count);
352 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
359 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
363 /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
364 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
365 * come in cp2112_raw_event or timeout. There will only be one of these
366 * in flight at any one time. The timeout is extremely large and is a
367 * last resort if the CP2112 has died. If we do timeout we don't expect
368 * to receive the response which would cause data races, it's not like
369 * we can do anything about it anyway.
371 ret = wait_event_interruptible_timeout(dev->wait,
372 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
373 if (-ERESTARTSYS == ret)
378 atomic_set(avail, 0);
382 static int cp2112_xfer_status(struct cp2112_device *dev)
384 struct hid_device *hdev = dev->hdev;
388 buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
390 atomic_set(&dev->xfer_avail, 0);
392 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
394 hid_warn(hdev, "Error requesting status: %d\n", ret);
398 ret = cp2112_wait(dev, &dev->xfer_avail);
402 return dev->xfer_status;
405 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
407 struct hid_device *hdev = dev->hdev;
408 struct cp2112_force_read_report report;
411 if (size > sizeof(dev->read_data))
412 size = sizeof(dev->read_data);
413 report.report = CP2112_DATA_READ_FORCE_SEND;
414 report.length = cpu_to_be16(size);
416 atomic_set(&dev->read_avail, 0);
418 ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
421 hid_warn(hdev, "Error requesting data: %d\n", ret);
425 ret = cp2112_wait(dev, &dev->read_avail);
429 hid_dbg(hdev, "read %d of %zd bytes requested\n",
430 dev->read_length, size);
432 if (size > dev->read_length)
433 size = dev->read_length;
435 memcpy(data, dev->read_data, size);
436 return dev->read_length;
439 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
441 struct cp2112_read_req_report *report = buf;
443 if (length < 1 || length > 512)
446 report->report = CP2112_DATA_READ_REQUEST;
447 report->slave_address = slave_address << 1;
448 report->length = cpu_to_be16(length);
449 return sizeof(*report);
452 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
453 u8 command, u8 *data, u8 data_length)
455 struct cp2112_write_read_req_report *report = buf;
457 if (length < 1 || length > 512
458 || data_length > sizeof(report->target_address) - 1)
461 report->report = CP2112_DATA_WRITE_READ_REQUEST;
462 report->slave_address = slave_address << 1;
463 report->length = cpu_to_be16(length);
464 report->target_address_length = data_length + 1;
465 report->target_address[0] = command;
466 memcpy(&report->target_address[1], data, data_length);
467 return data_length + 6;
470 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
473 struct cp2112_write_req_report *report = buf;
475 if (data_length > sizeof(report->data) - 1)
478 report->report = CP2112_DATA_WRITE_REQUEST;
479 report->slave_address = slave_address << 1;
480 report->length = data_length + 1;
481 report->data[0] = command;
482 memcpy(&report->data[1], data, data_length);
483 return data_length + 4;
486 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
489 struct cp2112_write_req_report *report = buf;
491 if (data_length > sizeof(report->data))
494 report->report = CP2112_DATA_WRITE_REQUEST;
495 report->slave_address = slave_address << 1;
496 report->length = data_length;
497 memcpy(report->data, data, data_length);
498 return data_length + 3;
501 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
502 u8 *addr, int addr_length,
505 struct cp2112_write_read_req_report *report = buf;
507 if (read_length < 1 || read_length > 512 ||
508 addr_length > sizeof(report->target_address))
511 report->report = CP2112_DATA_WRITE_READ_REQUEST;
512 report->slave_address = slave_address << 1;
513 report->length = cpu_to_be16(read_length);
514 report->target_address_length = addr_length;
515 memcpy(report->target_address, addr, addr_length);
516 return addr_length + 5;
519 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
522 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
523 struct hid_device *hdev = dev->hdev;
526 ssize_t read_length = 0;
528 unsigned int retries;
531 hid_dbg(hdev, "I2C %d messages\n", num);
534 if (msgs->flags & I2C_M_RD) {
535 hid_dbg(hdev, "I2C read %#04x len %d\n",
536 msgs->addr, msgs->len);
537 read_length = msgs->len;
538 read_buf = msgs->buf;
539 count = cp2112_read_req(buf, msgs->addr, msgs->len);
541 hid_dbg(hdev, "I2C write %#04x len %d\n",
542 msgs->addr, msgs->len);
543 count = cp2112_i2c_write_req(buf, msgs->addr,
544 msgs->buf, msgs->len);
548 } else if (dev->hwversion > 1 && /* no repeated start in rev 1 */
550 msgs[0].addr == msgs[1].addr &&
551 !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
552 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
553 msgs[0].addr, msgs[0].len, msgs[1].len);
554 read_length = msgs[1].len;
555 read_buf = msgs[1].buf;
556 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
557 msgs[0].buf, msgs[0].len, msgs[1].len);
562 "Multi-message I2C transactions not supported\n");
566 ret = hid_hw_power(hdev, PM_HINT_FULLON);
568 hid_err(hdev, "power management error: %d\n", ret);
572 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
574 hid_warn(hdev, "Error starting transaction: %d\n", ret);
578 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
579 ret = cp2112_xfer_status(dev);
587 if (XFER_STATUS_RETRIES <= retries) {
588 hid_warn(hdev, "Transfer timed out, cancelling.\n");
589 buf[0] = CP2112_CANCEL_TRANSFER;
592 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
594 hid_warn(hdev, "Error cancelling transaction: %d\n",
601 for (count = 0; count < read_length;) {
602 ret = cp2112_read(dev, read_buf + count, read_length - count);
606 hid_err(hdev, "read returned 0\n");
611 if (count > read_length) {
613 * The hardware returned too much data.
614 * This is mostly harmless because cp2112_read()
615 * has a limit check so didn't overrun our
616 * buffer. Nevertheless, we return an error
617 * because something is seriously wrong and
618 * it shouldn't go unnoticed.
620 hid_err(hdev, "long read: %d > %zd\n",
621 ret, read_length - count + ret);
627 /* return the number of transferred messages */
631 hid_hw_power(hdev, PM_HINT_NORMAL);
632 hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
636 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
637 unsigned short flags, char read_write, u8 command,
638 int size, union i2c_smbus_data *data)
640 struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
641 struct hid_device *hdev = dev->hdev;
645 size_t read_length = 0;
646 unsigned int retries;
649 hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
650 read_write == I2C_SMBUS_WRITE ? "write" : "read",
651 addr, flags, command, size);
657 if (I2C_SMBUS_READ == read_write)
658 count = cp2112_read_req(buf, addr, read_length);
660 count = cp2112_write_req(buf, addr, command, NULL,
663 case I2C_SMBUS_BYTE_DATA:
666 if (I2C_SMBUS_READ == read_write)
667 count = cp2112_write_read_req(buf, addr, read_length,
670 count = cp2112_write_req(buf, addr, command,
673 case I2C_SMBUS_WORD_DATA:
675 word = cpu_to_le16(data->word);
677 if (I2C_SMBUS_READ == read_write)
678 count = cp2112_write_read_req(buf, addr, read_length,
681 count = cp2112_write_req(buf, addr, command,
684 case I2C_SMBUS_PROC_CALL:
685 size = I2C_SMBUS_WORD_DATA;
686 read_write = I2C_SMBUS_READ;
688 word = cpu_to_le16(data->word);
690 count = cp2112_write_read_req(buf, addr, read_length, command,
693 case I2C_SMBUS_I2C_BLOCK_DATA:
694 size = I2C_SMBUS_BLOCK_DATA;
696 case I2C_SMBUS_BLOCK_DATA:
697 if (I2C_SMBUS_READ == read_write) {
698 count = cp2112_write_read_req(buf, addr,
702 count = cp2112_write_req(buf, addr, command,
707 case I2C_SMBUS_BLOCK_PROC_CALL:
708 size = I2C_SMBUS_BLOCK_DATA;
709 read_write = I2C_SMBUS_READ;
711 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
712 command, data->block,
716 hid_warn(hdev, "Unsupported transaction %d\n", size);
723 ret = hid_hw_power(hdev, PM_HINT_FULLON);
725 hid_err(hdev, "power management error: %d\n", ret);
729 ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
731 hid_warn(hdev, "Error starting transaction: %d\n", ret);
735 for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
736 ret = cp2112_xfer_status(dev);
744 if (XFER_STATUS_RETRIES <= retries) {
745 hid_warn(hdev, "Transfer timed out, cancelling.\n");
746 buf[0] = CP2112_CANCEL_TRANSFER;
749 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
751 hid_warn(hdev, "Error cancelling transaction: %d\n",
758 if (I2C_SMBUS_WRITE == read_write) {
763 if (I2C_SMBUS_BLOCK_DATA == size)
766 ret = cp2112_read(dev, buf, read_length);
769 if (ret != read_length) {
770 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
777 case I2C_SMBUS_BYTE_DATA:
780 case I2C_SMBUS_WORD_DATA:
781 data->word = le16_to_cpup((__le16 *)buf);
783 case I2C_SMBUS_BLOCK_DATA:
784 if (read_length > I2C_SMBUS_BLOCK_MAX) {
789 memcpy(data->block, buf, read_length);
795 hid_hw_power(hdev, PM_HINT_NORMAL);
796 hid_dbg(hdev, "transfer finished: %d\n", ret);
800 static u32 cp2112_functionality(struct i2c_adapter *adap)
802 return I2C_FUNC_I2C |
803 I2C_FUNC_SMBUS_BYTE |
804 I2C_FUNC_SMBUS_BYTE_DATA |
805 I2C_FUNC_SMBUS_WORD_DATA |
806 I2C_FUNC_SMBUS_BLOCK_DATA |
807 I2C_FUNC_SMBUS_I2C_BLOCK |
808 I2C_FUNC_SMBUS_PROC_CALL |
809 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
812 static const struct i2c_algorithm smbus_algorithm = {
813 .master_xfer = cp2112_i2c_xfer,
814 .smbus_xfer = cp2112_xfer,
815 .functionality = cp2112_functionality,
818 static int cp2112_get_usb_config(struct hid_device *hdev,
819 struct cp2112_usb_config_report *cfg)
823 ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
825 if (ret != sizeof(*cfg)) {
826 hid_err(hdev, "error reading usb config: %d\n", ret);
835 static int cp2112_set_usb_config(struct hid_device *hdev,
836 struct cp2112_usb_config_report *cfg)
840 BUG_ON(cfg->report != CP2112_USB_CONFIG);
842 ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
844 if (ret != sizeof(*cfg)) {
845 hid_err(hdev, "error writing usb config: %d\n", ret);
854 static void chmod_sysfs_attrs(struct hid_device *hdev);
856 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
857 static ssize_t name##_store(struct device *kdev, \
858 struct device_attribute *attr, const char *buf, \
861 struct hid_device *hdev = to_hid_device(kdev); \
862 struct cp2112_usb_config_report cfg; \
863 int ret = cp2112_get_usb_config(hdev, &cfg); \
867 ret = cp2112_set_usb_config(hdev, &cfg); \
870 chmod_sysfs_attrs(hdev); \
873 static ssize_t name##_show(struct device *kdev, \
874 struct device_attribute *attr, 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); \
881 return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
883 static DEVICE_ATTR_RW(name);
885 CP2112_CONFIG_ATTR(vendor_id, ({
888 if (sscanf(buf, "%hi", &vid) != 1)
891 cfg.vid = cpu_to_le16(vid);
893 }), "0x%04x\n", le16_to_cpu(cfg.vid));
895 CP2112_CONFIG_ATTR(product_id, ({
898 if (sscanf(buf, "%hi", &pid) != 1)
901 cfg.pid = cpu_to_le16(pid);
903 }), "0x%04x\n", le16_to_cpu(cfg.pid));
905 CP2112_CONFIG_ATTR(max_power, ({
908 if (sscanf(buf, "%i", &mA) != 1)
911 cfg.max_power = (mA + 1) / 2;
913 }), "%u mA\n", cfg.max_power * 2);
915 CP2112_CONFIG_ATTR(power_mode, ({
916 if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
920 }), "%u\n", cfg.power_mode);
922 CP2112_CONFIG_ATTR(release_version, ({
923 if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
928 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
930 #undef CP2112_CONFIG_ATTR
932 struct cp2112_pstring_attribute {
933 struct device_attribute attr;
934 unsigned char report;
937 static ssize_t pstr_store(struct device *kdev,
938 struct device_attribute *kattr, const char *buf,
941 struct hid_device *hdev = to_hid_device(kdev);
942 struct cp2112_pstring_attribute *attr =
943 container_of(kattr, struct cp2112_pstring_attribute, attr);
944 struct cp2112_string_report report;
947 memset(&report, 0, sizeof(report));
949 ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
950 report.string, ARRAY_SIZE(report.string));
951 report.report = attr->report;
952 report.length = ret * sizeof(report.string[0]) + 2;
953 report.type = USB_DT_STRING;
955 ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
957 if (ret != report.length + 1) {
958 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
965 chmod_sysfs_attrs(hdev);
969 static ssize_t pstr_show(struct device *kdev,
970 struct device_attribute *kattr, char *buf)
972 struct hid_device *hdev = to_hid_device(kdev);
973 struct cp2112_pstring_attribute *attr =
974 container_of(kattr, struct cp2112_pstring_attribute, attr);
975 struct cp2112_string_report report;
979 ret = cp2112_hid_get(hdev, attr->report, &report.report,
980 sizeof(report) - 1, HID_FEATURE_REPORT);
982 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
989 if (report.length < 2) {
990 hid_err(hdev, "invalid %s string length: %d\n",
991 kattr->attr.name, report.length);
995 length = report.length > ret - 1 ? ret - 1 : report.length;
996 length = (length - 2) / sizeof(report.string[0]);
997 ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1003 #define CP2112_PSTR_ATTR(name, _report) \
1004 static struct cp2112_pstring_attribute dev_attr_##name = { \
1005 .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1006 .report = _report, \
1009 CP2112_PSTR_ATTR(manufacturer, CP2112_MANUFACTURER_STRING);
1010 CP2112_PSTR_ATTR(product, CP2112_PRODUCT_STRING);
1011 CP2112_PSTR_ATTR(serial, CP2112_SERIAL_STRING);
1013 #undef CP2112_PSTR_ATTR
1015 static const struct attribute_group cp2112_attr_group = {
1016 .attrs = (struct attribute *[]){
1017 &dev_attr_vendor_id.attr,
1018 &dev_attr_product_id.attr,
1019 &dev_attr_max_power.attr,
1020 &dev_attr_power_mode.attr,
1021 &dev_attr_release_version.attr,
1022 &dev_attr_manufacturer.attr.attr,
1023 &dev_attr_product.attr.attr,
1024 &dev_attr_serial.attr.attr,
1029 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1030 * PROM have already been programmed. We do not depend on this preventing
1031 * writing to these attributes since the CP2112 will simply ignore writes to
1032 * already-programmed fields. This is why there is no sense in fixing this
1035 static void chmod_sysfs_attrs(struct hid_device *hdev)
1037 struct attribute **attr;
1041 ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1042 HID_FEATURE_REPORT);
1043 if (ret != sizeof(buf)) {
1044 hid_err(hdev, "error reading lock byte: %d\n", ret);
1048 for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1049 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1050 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1052 hid_err(hdev, "error chmoding sysfs file %s\n",
1058 static void cp2112_gpio_irq_ack(struct irq_data *d)
1062 static void cp2112_gpio_irq_mask(struct irq_data *d)
1064 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1065 struct cp2112_device *dev = gpiochip_get_data(gc);
1067 __clear_bit(d->hwirq, &dev->irq_mask);
1070 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1072 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1073 struct cp2112_device *dev = gpiochip_get_data(gc);
1075 __set_bit(d->hwirq, &dev->irq_mask);
1078 static void cp2112_gpio_poll_callback(struct work_struct *work)
1080 struct cp2112_device *dev = container_of(work, struct cp2112_device,
1081 gpio_poll_worker.work);
1084 u8 virqs = (u8)dev->irq_mask;
1088 ret = cp2112_gpio_get_all(&dev->gc);
1089 if (ret == -ENODEV) /* the hardware has been disconnected */
1097 virq = ffs(virqs) - 1;
1098 virqs &= ~BIT(virq);
1100 if (!dev->gc.to_irq)
1103 irq = dev->gc.to_irq(&dev->gc, virq);
1105 d = irq_get_irq_data(irq);
1109 irq_type = irqd_get_trigger_type(d);
1111 if (gpio_mask & BIT(virq)) {
1114 if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1115 handle_nested_irq(irq);
1117 if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1118 !(dev->gpio_prev_state & BIT(virq)))
1119 handle_nested_irq(irq);
1123 if (irq_type & IRQ_TYPE_LEVEL_LOW)
1124 handle_nested_irq(irq);
1126 if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1127 (dev->gpio_prev_state & BIT(virq)))
1128 handle_nested_irq(irq);
1132 dev->gpio_prev_state = gpio_mask;
1136 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1140 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1142 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1143 struct cp2112_device *dev = gpiochip_get_data(gc);
1145 INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1147 cp2112_gpio_direction_input(gc, d->hwirq);
1149 if (!dev->gpio_poll) {
1150 dev->gpio_poll = true;
1151 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1154 cp2112_gpio_irq_unmask(d);
1158 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1160 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1161 struct cp2112_device *dev = gpiochip_get_data(gc);
1163 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1166 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1171 static struct irq_chip cp2112_gpio_irqchip = {
1172 .name = "cp2112-gpio",
1173 .irq_startup = cp2112_gpio_irq_startup,
1174 .irq_shutdown = cp2112_gpio_irq_shutdown,
1175 .irq_ack = cp2112_gpio_irq_ack,
1176 .irq_mask = cp2112_gpio_irq_mask,
1177 .irq_unmask = cp2112_gpio_irq_unmask,
1178 .irq_set_type = cp2112_gpio_irq_type,
1181 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1189 dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1191 if (IS_ERR(dev->desc[pin])) {
1192 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1193 return PTR_ERR(dev->desc[pin]);
1196 ret = gpiochip_lock_as_irq(&dev->gc, pin);
1198 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1202 ret = gpiod_to_irq(dev->desc[pin]);
1204 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1211 gpiochip_unlock_as_irq(&dev->gc, pin);
1213 gpiochip_free_own_desc(dev->desc[pin]);
1214 dev->desc[pin] = NULL;
1218 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1220 struct cp2112_device *dev;
1222 struct cp2112_smbus_config_report config;
1225 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1229 dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1231 if (!dev->in_out_buffer)
1234 mutex_init(&dev->lock);
1236 ret = hid_parse(hdev);
1238 hid_err(hdev, "parse failed\n");
1242 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1244 hid_err(hdev, "hw start failed\n");
1248 ret = hid_hw_open(hdev);
1250 hid_err(hdev, "hw open failed\n");
1254 ret = hid_hw_power(hdev, PM_HINT_FULLON);
1256 hid_err(hdev, "power management error: %d\n", ret);
1260 ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1261 HID_FEATURE_REPORT);
1262 if (ret != sizeof(buf)) {
1263 hid_err(hdev, "error requesting version\n");
1266 goto err_power_normal;
1269 hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1272 ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1273 sizeof(config), HID_FEATURE_REPORT);
1274 if (ret != sizeof(config)) {
1275 hid_err(hdev, "error requesting SMBus config\n");
1278 goto err_power_normal;
1281 config.retry_time = cpu_to_be16(1);
1283 ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1284 HID_FEATURE_REPORT);
1285 if (ret != sizeof(config)) {
1286 hid_err(hdev, "error setting SMBus config\n");
1289 goto err_power_normal;
1292 hid_set_drvdata(hdev, (void *)dev);
1294 dev->adap.owner = THIS_MODULE;
1295 dev->adap.class = I2C_CLASS_HWMON;
1296 dev->adap.algo = &smbus_algorithm;
1297 dev->adap.algo_data = dev;
1298 dev->adap.dev.parent = &hdev->dev;
1299 snprintf(dev->adap.name, sizeof(dev->adap.name),
1300 "CP2112 SMBus Bridge on hiddev%d", hdev->minor);
1301 dev->hwversion = buf[2];
1302 init_waitqueue_head(&dev->wait);
1304 hid_device_io_start(hdev);
1305 ret = i2c_add_adapter(&dev->adap);
1306 hid_device_io_stop(hdev);
1309 hid_err(hdev, "error registering i2c adapter\n");
1310 goto err_power_normal;
1313 hid_dbg(hdev, "adapter registered\n");
1315 dev->gc.label = "cp2112_gpio";
1316 dev->gc.direction_input = cp2112_gpio_direction_input;
1317 dev->gc.direction_output = cp2112_gpio_direction_output;
1318 dev->gc.set = cp2112_gpio_set;
1319 dev->gc.get = cp2112_gpio_get;
1322 dev->gc.can_sleep = 1;
1323 dev->gc.parent = &hdev->dev;
1325 ret = gpiochip_add_data(&dev->gc, dev);
1327 hid_err(hdev, "error registering gpio chip\n");
1331 ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1333 hid_err(hdev, "error creating sysfs attrs\n");
1334 goto err_gpiochip_remove;
1337 chmod_sysfs_attrs(hdev);
1338 hid_hw_power(hdev, PM_HINT_NORMAL);
1340 ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1341 handle_simple_irq, IRQ_TYPE_NONE);
1343 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1344 goto err_sysfs_remove;
1350 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1351 err_gpiochip_remove:
1352 gpiochip_remove(&dev->gc);
1354 i2c_del_adapter(&dev->adap);
1356 hid_hw_power(hdev, PM_HINT_NORMAL);
1364 static void cp2112_remove(struct hid_device *hdev)
1366 struct cp2112_device *dev = hid_get_drvdata(hdev);
1369 sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1370 i2c_del_adapter(&dev->adap);
1372 if (dev->gpio_poll) {
1373 dev->gpio_poll = false;
1374 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1377 for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1378 gpiochip_unlock_as_irq(&dev->gc, i);
1379 gpiochip_free_own_desc(dev->desc[i]);
1382 gpiochip_remove(&dev->gc);
1383 /* i2c_del_adapter has finished removing all i2c devices from our
1384 * adapter. Well behaved devices should no longer call our cp2112_xfer
1385 * and should have waited for any pending calls to finish. It has also
1386 * waited for device_unregister(&adap->dev) to complete. Therefore we
1387 * can safely free our struct cp2112_device.
1393 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1396 struct cp2112_device *dev = hid_get_drvdata(hdev);
1397 struct cp2112_xfer_status_report *xfer = (void *)data;
1400 case CP2112_TRANSFER_STATUS_RESPONSE:
1401 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1402 xfer->status0, xfer->status1,
1403 be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1405 switch (xfer->status0) {
1407 dev->xfer_status = -EAGAIN;
1410 dev->xfer_status = -EBUSY;
1412 case STATUS0_COMPLETE:
1413 dev->xfer_status = be16_to_cpu(xfer->length);
1416 switch (xfer->status1) {
1417 case STATUS1_TIMEOUT_NACK:
1418 case STATUS1_TIMEOUT_BUS:
1419 dev->xfer_status = -ETIMEDOUT;
1422 dev->xfer_status = -EIO;
1427 dev->xfer_status = -EINVAL;
1431 atomic_set(&dev->xfer_avail, 1);
1433 case CP2112_DATA_READ_RESPONSE:
1434 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1436 dev->read_length = data[2];
1437 if (dev->read_length > sizeof(dev->read_data))
1438 dev->read_length = sizeof(dev->read_data);
1440 memcpy(dev->read_data, &data[3], dev->read_length);
1441 atomic_set(&dev->read_avail, 1);
1444 hid_err(hdev, "unknown report\n");
1449 wake_up_interruptible(&dev->wait);
1453 static struct hid_driver cp2112_driver = {
1455 .id_table = cp2112_devices,
1456 .probe = cp2112_probe,
1457 .remove = cp2112_remove,
1458 .raw_event = cp2112_raw_event,
1461 module_hid_driver(cp2112_driver);
1462 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1463 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1464 MODULE_LICENSE("GPL");