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/cleanup.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/mutex.h>
  27#include <linux/nls.h>
  28#include <linux/string_choices.h>
  29#include <linux/usb/ch9.h>
  30#include "hid-ids.h"
  31
  32#define CP2112_REPORT_MAX_LENGTH		64
  33#define CP2112_GPIO_CONFIG_LENGTH		5
  34#define CP2112_GPIO_GET_LENGTH			2
  35#define CP2112_GPIO_SET_LENGTH			3
  36#define CP2112_GPIO_MAX_GPIO			8
  37#define CP2112_GPIO_ALL_GPIO_MASK		GENMASK(7, 0)
  38
  39enum {
  40	CP2112_GPIO_CONFIG		= 0x02,
  41	CP2112_GPIO_GET			= 0x03,
  42	CP2112_GPIO_SET			= 0x04,
  43	CP2112_GET_VERSION_INFO		= 0x05,
  44	CP2112_SMBUS_CONFIG		= 0x06,
  45	CP2112_DATA_READ_REQUEST	= 0x10,
  46	CP2112_DATA_WRITE_READ_REQUEST	= 0x11,
  47	CP2112_DATA_READ_FORCE_SEND	= 0x12,
  48	CP2112_DATA_READ_RESPONSE	= 0x13,
  49	CP2112_DATA_WRITE_REQUEST	= 0x14,
  50	CP2112_TRANSFER_STATUS_REQUEST	= 0x15,
  51	CP2112_TRANSFER_STATUS_RESPONSE	= 0x16,
  52	CP2112_CANCEL_TRANSFER		= 0x17,
  53	CP2112_LOCK_BYTE		= 0x20,
  54	CP2112_USB_CONFIG		= 0x21,
  55	CP2112_MANUFACTURER_STRING	= 0x22,
  56	CP2112_PRODUCT_STRING		= 0x23,
  57	CP2112_SERIAL_STRING		= 0x24,
  58};
  59
  60enum {
  61	STATUS0_IDLE		= 0x00,
  62	STATUS0_BUSY		= 0x01,
  63	STATUS0_COMPLETE	= 0x02,
  64	STATUS0_ERROR		= 0x03,
  65};
  66
  67enum {
  68	STATUS1_TIMEOUT_NACK		= 0x00,
  69	STATUS1_TIMEOUT_BUS		= 0x01,
  70	STATUS1_ARBITRATION_LOST	= 0x02,
  71	STATUS1_READ_INCOMPLETE		= 0x03,
  72	STATUS1_WRITE_INCOMPLETE	= 0x04,
  73	STATUS1_SUCCESS			= 0x05,
  74};
  75
  76struct cp2112_smbus_config_report {
  77	u8 report;		/* CP2112_SMBUS_CONFIG */
  78	__be32 clock_speed;	/* Hz */
  79	u8 device_address;	/* Stored in the upper 7 bits */
  80	u8 auto_send_read;	/* 1 = enabled, 0 = disabled */
  81	__be16 write_timeout;	/* ms, 0 = no timeout */
  82	__be16 read_timeout;	/* ms, 0 = no timeout */
  83	u8 scl_low_timeout;	/* 1 = enabled, 0 = disabled */
  84	__be16 retry_time;	/* # of retries, 0 = no limit */
  85} __packed;
  86
  87struct cp2112_usb_config_report {
  88	u8 report;	/* CP2112_USB_CONFIG */
  89	__le16 vid;	/* Vendor ID */
  90	__le16 pid;	/* Product ID */
  91	u8 max_power;	/* Power requested in 2mA units */
  92	u8 power_mode;	/* 0x00 = bus powered
  93			   0x01 = self powered & regulator off
  94			   0x02 = self powered & regulator on */
  95	u8 release_major;
  96	u8 release_minor;
  97	u8 mask;	/* What fields to program */
  98} __packed;
  99
 100struct cp2112_read_req_report {
 101	u8 report;	/* CP2112_DATA_READ_REQUEST */
 102	u8 slave_address;
 103	__be16 length;
 104} __packed;
 105
 106struct cp2112_write_read_req_report {
 107	u8 report;	/* CP2112_DATA_WRITE_READ_REQUEST */
 108	u8 slave_address;
 109	__be16 length;
 110	u8 target_address_length;
 111	u8 target_address[16];
 112} __packed;
 113
 114struct cp2112_write_req_report {
 115	u8 report;	/* CP2112_DATA_WRITE_REQUEST */
 116	u8 slave_address;
 117	u8 length;
 118	u8 data[61];
 119} __packed;
 120
 121struct cp2112_force_read_report {
 122	u8 report;	/* CP2112_DATA_READ_FORCE_SEND */
 123	__be16 length;
 124} __packed;
 125
 126struct cp2112_xfer_status_report {
 127	u8 report;	/* CP2112_TRANSFER_STATUS_RESPONSE */
 128	u8 status0;	/* STATUS0_* */
 129	u8 status1;	/* STATUS1_* */
 130	__be16 retries;
 131	__be16 length;
 132} __packed;
 133
 134struct cp2112_string_report {
 135	u8 dummy;		/* force .string to be aligned */
 136	struct_group_attr(contents, __packed,
 137		u8 report;		/* CP2112_*_STRING */
 138		u8 length;		/* length in bytes of everything after .report */
 139		u8 type;		/* USB_DT_STRING */
 140		wchar_t string[30];	/* UTF16_LITTLE_ENDIAN string */
 141	);
 142} __packed;
 143
 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. */
 147static const int XFER_STATUS_RETRIES = 10;
 148
 149/* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
 150   CP2112_TRANSFER_STATUS_RESPONSE. */
 151static const int RESPONSE_TIMEOUT = 50;
 152
 153static const struct hid_device_id cp2112_devices[] = {
 154	{ HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 155	{ }
 156};
 157MODULE_DEVICE_TABLE(hid, cp2112_devices);
 158
 159struct cp2112_device {
 160	struct i2c_adapter adap;
 161	struct hid_device *hdev;
 162	wait_queue_head_t wait;
 163	u8 read_data[61];
 164	u8 read_length;
 165	u8 hwversion;
 166	int xfer_status;
 167	atomic_t read_avail;
 168	atomic_t xfer_avail;
 169	struct gpio_chip gc;
 170	u8 *in_out_buffer;
 171	struct mutex lock;
 172
 173	bool gpio_poll;
 174	struct delayed_work gpio_poll_worker;
 175	unsigned long irq_mask;
 176	u8 gpio_prev_state;
 177};
 178
 179static int gpio_push_pull = CP2112_GPIO_ALL_GPIO_MASK;
 180module_param(gpio_push_pull, int, 0644);
 181MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 182
 183static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 184{
 185	struct cp2112_device *dev = gpiochip_get_data(chip);
 186	struct hid_device *hdev = dev->hdev;
 187	u8 *buf = dev->in_out_buffer;
 188	int ret;
 189
 190	guard(mutex)(&dev->lock);
 191
 192	ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 193				 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 194				 HID_REQ_GET_REPORT);
 195	if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 196		hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 197		if (ret >= 0)
 198			ret = -EIO;
 199		return ret;
 200	}
 201
 202	buf[1] &= ~BIT(offset);
 203	buf[2] = gpio_push_pull;
 204
 205	ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 206				 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 207				 HID_REQ_SET_REPORT);
 208	if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 209		hid_err(hdev, "error setting GPIO config: %d\n", ret);
 210		if (ret >= 0)
 211			ret = -EIO;
 212		return ret;
 213	}
 214
 215	return 0;
 216}
 217
 218static int cp2112_gpio_set_unlocked(struct cp2112_device *dev,
 219				    unsigned int offset, int value)
 220{
 221	struct hid_device *hdev = dev->hdev;
 222	u8 *buf = dev->in_out_buffer;
 223	int ret;
 224
 225	buf[0] = CP2112_GPIO_SET;
 226	buf[1] = value ? CP2112_GPIO_ALL_GPIO_MASK : 0;
 227	buf[2] = BIT(offset);
 228
 229	ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
 230				 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
 231				 HID_REQ_SET_REPORT);
 232	if (ret != CP2112_GPIO_SET_LENGTH) {
 233		hid_err(hdev, "error setting GPIO values: %d\n", ret);
 234		return ret < 0 ? ret : -EIO;
 235	}
 236
 237	return 0;
 238}
 239
 240static int cp2112_gpio_set(struct gpio_chip *chip, unsigned int offset,
 241			   int value)
 242{
 243	struct cp2112_device *dev = gpiochip_get_data(chip);
 244
 245	guard(mutex)(&dev->lock);
 246
 247	return cp2112_gpio_set_unlocked(dev, offset, value);
 248}
 249
 250static int cp2112_gpio_get_all(struct gpio_chip *chip)
 251{
 252	struct cp2112_device *dev = gpiochip_get_data(chip);
 253	struct hid_device *hdev = dev->hdev;
 254	u8 *buf = dev->in_out_buffer;
 255	int ret;
 256
 257	guard(mutex)(&dev->lock);
 258
 259	ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
 260				 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
 261				 HID_REQ_GET_REPORT);
 262	if (ret != CP2112_GPIO_GET_LENGTH) {
 263		hid_err(hdev, "error requesting GPIO values: %d\n", ret);
 264		return ret < 0 ? ret : -EIO;
 265	}
 266
 267	return buf[1];
 268}
 269
 270static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
 271{
 272	int ret;
 273
 274	ret = cp2112_gpio_get_all(chip);
 275	if (ret < 0)
 276		return ret;
 277
 278	return (ret >> offset) & 1;
 279}
 280
 281static int cp2112_gpio_direction_output(struct gpio_chip *chip,
 282					unsigned offset, int value)
 283{
 284	struct cp2112_device *dev = gpiochip_get_data(chip);
 285	struct hid_device *hdev = dev->hdev;
 286	u8 *buf = dev->in_out_buffer;
 287	int ret;
 288
 289	guard(mutex)(&dev->lock);
 290
 291	ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 292				 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 293				 HID_REQ_GET_REPORT);
 294	if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 295		hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 296		return ret < 0 ? ret : -EIO;
 297	}
 298
 299	buf[1] |= 1 << offset;
 300	buf[2] = gpio_push_pull;
 301
 302	ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 303				 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 304				 HID_REQ_SET_REPORT);
 305	if (ret < 0) {
 306		hid_err(hdev, "error setting GPIO config: %d\n", ret);
 307		return ret;
 308	}
 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	return cp2112_gpio_set_unlocked(dev, offset, value);
 315}
 316
 317static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
 318			  u8 *data, size_t count, unsigned char report_type)
 319{
 320	u8 *buf;
 321	int ret;
 322
 323	buf = kmalloc(count, GFP_KERNEL);
 324	if (!buf)
 325		return -ENOMEM;
 326
 327	ret = hid_hw_raw_request(hdev, report_number, buf, count,
 328				       report_type, HID_REQ_GET_REPORT);
 329	memcpy(data, buf, count);
 330	kfree(buf);
 331	return ret;
 332}
 333
 334static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
 335			     unsigned char report_type)
 336{
 337	u8 *buf;
 338	int ret;
 339
 340	buf = kmemdup(data, count, GFP_KERNEL);
 341	if (!buf)
 342		return -ENOMEM;
 343
 344	if (report_type == HID_OUTPUT_REPORT)
 345		ret = hid_hw_output_report(hdev, buf, count);
 346	else
 347		ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
 348				HID_REQ_SET_REPORT);
 349
 350	kfree(buf);
 351	return ret;
 352}
 353
 354static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
 355{
 356	int ret = 0;
 357
 358	/* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
 359	 * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
 360	 * come in cp2112_raw_event or timeout. There will only be one of these
 361	 * in flight at any one time. The timeout is extremely large and is a
 362	 * last resort if the CP2112 has died. If we do timeout we don't expect
 363	 * to receive the response which would cause data races, it's not like
 364	 * we can do anything about it anyway.
 365	 */
 366	ret = wait_event_interruptible_timeout(dev->wait,
 367		atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
 368	if (-ERESTARTSYS == ret)
 369		return ret;
 370	if (!ret)
 371		return -ETIMEDOUT;
 372
 373	atomic_set(avail, 0);
 374	return 0;
 375}
 376
 377static int cp2112_xfer_status(struct cp2112_device *dev)
 378{
 379	struct hid_device *hdev = dev->hdev;
 380	u8 buf[2];
 381	int ret;
 382
 383	buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
 384	buf[1] = 0x01;
 385	atomic_set(&dev->xfer_avail, 0);
 386
 387	ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 388	if (ret < 0) {
 389		hid_warn(hdev, "Error requesting status: %d\n", ret);
 390		return ret;
 391	}
 392
 393	ret = cp2112_wait(dev, &dev->xfer_avail);
 394	if (ret)
 395		return ret;
 396
 397	return dev->xfer_status;
 398}
 399
 400static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
 401{
 402	struct hid_device *hdev = dev->hdev;
 403	struct cp2112_force_read_report report;
 404	int ret;
 405
 406	if (size > sizeof(dev->read_data))
 407		size = sizeof(dev->read_data);
 408	report.report = CP2112_DATA_READ_FORCE_SEND;
 409	report.length = cpu_to_be16(size);
 410
 411	atomic_set(&dev->read_avail, 0);
 412
 413	ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
 414				HID_OUTPUT_REPORT);
 415	if (ret < 0) {
 416		hid_warn(hdev, "Error requesting data: %d\n", ret);
 417		return ret;
 418	}
 419
 420	ret = cp2112_wait(dev, &dev->read_avail);
 421	if (ret)
 422		return ret;
 423
 424	hid_dbg(hdev, "read %d of %zd bytes requested\n",
 425		dev->read_length, size);
 426
 427	if (size > dev->read_length)
 428		size = dev->read_length;
 429
 430	memcpy(data, dev->read_data, size);
 431	return dev->read_length;
 432}
 433
 434static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
 435{
 436	struct cp2112_read_req_report *report = buf;
 437
 438	if (length < 1 || length > 512)
 439		return -EINVAL;
 440
 441	report->report = CP2112_DATA_READ_REQUEST;
 442	report->slave_address = slave_address << 1;
 443	report->length = cpu_to_be16(length);
 444	return sizeof(*report);
 445}
 446
 447static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
 448				 u8 command, u8 *data, u8 data_length)
 449{
 450	struct cp2112_write_read_req_report *report = buf;
 451
 452	if (length < 1 || length > 512
 453	    || data_length > sizeof(report->target_address) - 1)
 454		return -EINVAL;
 455
 456	report->report = CP2112_DATA_WRITE_READ_REQUEST;
 457	report->slave_address = slave_address << 1;
 458	report->length = cpu_to_be16(length);
 459	report->target_address_length = data_length + 1;
 460	report->target_address[0] = command;
 461	memcpy(&report->target_address[1], data, data_length);
 462	return data_length + 6;
 463}
 464
 465static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
 466			    u8 data_length)
 467{
 468	struct cp2112_write_req_report *report = buf;
 469
 470	if (data_length > sizeof(report->data) - 1)
 471		return -EINVAL;
 472
 473	report->report = CP2112_DATA_WRITE_REQUEST;
 474	report->slave_address = slave_address << 1;
 475	report->length = data_length + 1;
 476	report->data[0] = command;
 477	memcpy(&report->data[1], data, data_length);
 478	return data_length + 4;
 479}
 480
 481static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
 482				u8 data_length)
 483{
 484	struct cp2112_write_req_report *report = buf;
 485
 486	if (data_length > sizeof(report->data))
 487		return -EINVAL;
 488
 489	report->report = CP2112_DATA_WRITE_REQUEST;
 490	report->slave_address = slave_address << 1;
 491	report->length = data_length;
 492	memcpy(report->data, data, data_length);
 493	return data_length + 3;
 494}
 495
 496static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
 497				     u8 *addr, int addr_length,
 498				     int read_length)
 499{
 500	struct cp2112_write_read_req_report *report = buf;
 501
 502	if (read_length < 1 || read_length > 512 ||
 503	    addr_length > sizeof(report->target_address))
 504		return -EINVAL;
 505
 506	report->report = CP2112_DATA_WRITE_READ_REQUEST;
 507	report->slave_address = slave_address << 1;
 508	report->length = cpu_to_be16(read_length);
 509	report->target_address_length = addr_length;
 510	memcpy(report->target_address, addr, addr_length);
 511	return addr_length + 5;
 512}
 513
 514static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 515			   int num)
 516{
 517	struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 518	struct hid_device *hdev = dev->hdev;
 519	u8 buf[64];
 520	ssize_t count;
 521	ssize_t read_length = 0;
 522	u8 *read_buf = NULL;
 523	unsigned int retries;
 524	int ret;
 525
 526	hid_dbg(hdev, "I2C %d messages\n", num);
 527
 528	if (num == 1) {
 529		hid_dbg(hdev, "I2C %s %#04x len %d\n",
 530			str_read_write(msgs->flags & I2C_M_RD), msgs->addr, msgs->len);
 531		if (msgs->flags & I2C_M_RD) {
 532			read_length = msgs->len;
 533			read_buf = msgs->buf;
 534			count = cp2112_read_req(buf, msgs->addr, msgs->len);
 535		} else {
 536			count = cp2112_i2c_write_req(buf, msgs->addr,
 537						     msgs->buf, msgs->len);
 538		}
 539		if (count < 0)
 540			return count;
 541	} else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
 542		   num == 2 &&
 543		   msgs[0].addr == msgs[1].addr &&
 544		   !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
 545		hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
 546			msgs[0].addr, msgs[0].len, msgs[1].len);
 547		read_length = msgs[1].len;
 548		read_buf = msgs[1].buf;
 549		count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
 550				msgs[0].buf, msgs[0].len, msgs[1].len);
 551		if (count < 0)
 552			return count;
 553	} else {
 554		hid_err(hdev,
 555			"Multi-message I2C transactions not supported\n");
 556		return -EOPNOTSUPP;
 557	}
 558
 559	ret = hid_hw_power(hdev, PM_HINT_FULLON);
 560	if (ret < 0) {
 561		hid_err(hdev, "power management error: %d\n", ret);
 562		return ret;
 563	}
 564
 565	ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 566	if (ret < 0) {
 567		hid_warn(hdev, "Error starting transaction: %d\n", ret);
 568		goto power_normal;
 569	}
 570
 571	for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 572		ret = cp2112_xfer_status(dev);
 573		if (-EBUSY == ret)
 574			continue;
 575		if (ret < 0)
 576			goto power_normal;
 577		break;
 578	}
 579
 580	if (XFER_STATUS_RETRIES <= retries) {
 581		hid_warn(hdev, "Transfer timed out, cancelling.\n");
 582		buf[0] = CP2112_CANCEL_TRANSFER;
 583		buf[1] = 0x01;
 584
 585		ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 586		if (ret < 0)
 587			hid_warn(hdev, "Error cancelling transaction: %d\n",
 588				 ret);
 589
 590		ret = -ETIMEDOUT;
 591		goto power_normal;
 592	}
 593
 594	for (count = 0; count < read_length;) {
 595		ret = cp2112_read(dev, read_buf + count, read_length - count);
 596		if (ret < 0)
 597			goto power_normal;
 598		if (ret == 0) {
 599			hid_err(hdev, "read returned 0\n");
 600			ret = -EIO;
 601			goto power_normal;
 602		}
 603		count += ret;
 604		if (count > read_length) {
 605			/*
 606			 * The hardware returned too much data.
 607			 * This is mostly harmless because cp2112_read()
 608			 * has a limit check so didn't overrun our
 609			 * buffer.  Nevertheless, we return an error
 610			 * because something is seriously wrong and
 611			 * it shouldn't go unnoticed.
 612			 */
 613			hid_err(hdev, "long read: %d > %zd\n",
 614				ret, read_length - count + ret);
 615			ret = -EIO;
 616			goto power_normal;
 617		}
 618	}
 619
 620	/* return the number of transferred messages */
 621	ret = num;
 622
 623power_normal:
 624	hid_hw_power(hdev, PM_HINT_NORMAL);
 625	hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
 626	return ret;
 627}
 628
 629static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
 630		       unsigned short flags, char read_write, u8 command,
 631		       int size, union i2c_smbus_data *data)
 632{
 633	struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 634	struct hid_device *hdev = dev->hdev;
 635	u8 buf[64];
 636	__le16 word;
 637	ssize_t count;
 638	size_t read_length = 0;
 639	unsigned int retries;
 640	int ret;
 641
 642	hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
 643		str_write_read(read_write == I2C_SMBUS_WRITE),
 644		addr, flags, command, size);
 645
 646	switch (size) {
 647	case I2C_SMBUS_BYTE:
 648		read_length = 1;
 649
 650		if (I2C_SMBUS_READ == read_write)
 651			count = cp2112_read_req(buf, addr, read_length);
 652		else
 653			count = cp2112_write_req(buf, addr, command, NULL,
 654						 0);
 655		break;
 656	case I2C_SMBUS_BYTE_DATA:
 657		read_length = 1;
 658
 659		if (I2C_SMBUS_READ == read_write)
 660			count = cp2112_write_read_req(buf, addr, read_length,
 661						      command, NULL, 0);
 662		else
 663			count = cp2112_write_req(buf, addr, command,
 664						 &data->byte, 1);
 665		break;
 666	case I2C_SMBUS_WORD_DATA:
 667		read_length = 2;
 668		word = cpu_to_le16(data->word);
 669
 670		if (I2C_SMBUS_READ == read_write)
 671			count = cp2112_write_read_req(buf, addr, read_length,
 672						      command, NULL, 0);
 673		else
 674			count = cp2112_write_req(buf, addr, command,
 675						 (u8 *)&word, 2);
 676		break;
 677	case I2C_SMBUS_PROC_CALL:
 678		size = I2C_SMBUS_WORD_DATA;
 679		read_write = I2C_SMBUS_READ;
 680		read_length = 2;
 681		word = cpu_to_le16(data->word);
 682
 683		count = cp2112_write_read_req(buf, addr, read_length, command,
 684					      (u8 *)&word, 2);
 685		break;
 686	case I2C_SMBUS_I2C_BLOCK_DATA:
 687		if (read_write == I2C_SMBUS_READ) {
 688			read_length = data->block[0];
 689			count = cp2112_write_read_req(buf, addr, read_length,
 690						      command, NULL, 0);
 691		} else {
 692			/* Copy starts from data->block[1] so the length can
 693			 * be at max I2C_SMBUS_CLOCK_MAX + 1
 694			 */
 695
 696			if (data->block[0] > I2C_SMBUS_BLOCK_MAX + 1)
 697				count = -EINVAL;
 698			else
 699				count = cp2112_write_req(buf, addr, command,
 700						 data->block + 1,
 701						 data->block[0]);
 702		}
 703		break;
 704	case I2C_SMBUS_BLOCK_DATA:
 705		if (I2C_SMBUS_READ == read_write) {
 706			count = cp2112_write_read_req(buf, addr,
 707						      I2C_SMBUS_BLOCK_MAX,
 708						      command, NULL, 0);
 709		} else {
 710			/* data_length here is data->block[0] + 1
 711			 * so make sure that the data->block[0] is
 712			 * less than or equals I2C_SMBUS_BLOCK_MAX + 1
 713			*/
 714			if (data->block[0] > I2C_SMBUS_BLOCK_MAX + 1)
 715				count = -EINVAL;
 716			else
 717				count = cp2112_write_req(buf, addr, command,
 718						 data->block,
 719						 data->block[0] + 1);
 720		}
 721		break;
 722	case I2C_SMBUS_BLOCK_PROC_CALL:
 723		size = I2C_SMBUS_BLOCK_DATA;
 724		read_write = I2C_SMBUS_READ;
 725
 726		/* data_length is data->block[0] + 1, so
 727		 * so data->block[0] should be less than or
 728		 * equal to the I2C_SMBUS_BLOCK_MAX + 1
 729		*/
 730		if (data->block[0] > I2C_SMBUS_BLOCK_MAX + 1)
 731			count = -EINVAL;
 732		else
 733			count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 734					      command, data->block,
 735					      data->block[0] + 1);
 736		break;
 737	default:
 738		hid_warn(hdev, "Unsupported transaction %d\n", size);
 739		return -EOPNOTSUPP;
 740	}
 741
 742	if (count < 0)
 743		return count;
 744
 745	ret = hid_hw_power(hdev, PM_HINT_FULLON);
 746	if (ret < 0) {
 747		hid_err(hdev, "power management error: %d\n", ret);
 748		return ret;
 749	}
 750
 751	ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 752	if (ret < 0) {
 753		hid_warn(hdev, "Error starting transaction: %d\n", ret);
 754		goto power_normal;
 755	}
 756
 757	for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 758		ret = cp2112_xfer_status(dev);
 759		if (-EBUSY == ret)
 760			continue;
 761		if (ret < 0)
 762			goto power_normal;
 763		break;
 764	}
 765
 766	if (XFER_STATUS_RETRIES <= retries) {
 767		hid_warn(hdev, "Transfer timed out, cancelling.\n");
 768		buf[0] = CP2112_CANCEL_TRANSFER;
 769		buf[1] = 0x01;
 770
 771		ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 772		if (ret < 0)
 773			hid_warn(hdev, "Error cancelling transaction: %d\n",
 774				 ret);
 775
 776		ret = -ETIMEDOUT;
 777		goto power_normal;
 778	}
 779
 780	if (I2C_SMBUS_WRITE == read_write) {
 781		ret = 0;
 782		goto power_normal;
 783	}
 784
 785	if (I2C_SMBUS_BLOCK_DATA == size)
 786		read_length = ret;
 787
 788	ret = cp2112_read(dev, buf, read_length);
 789	if (ret < 0)
 790		goto power_normal;
 791	if (ret != read_length) {
 792		hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 793		ret = -EIO;
 794		goto power_normal;
 795	}
 796
 797	switch (size) {
 798	case I2C_SMBUS_BYTE:
 799	case I2C_SMBUS_BYTE_DATA:
 800		data->byte = buf[0];
 801		break;
 802	case I2C_SMBUS_WORD_DATA:
 803		data->word = le16_to_cpup((__le16 *)buf);
 804		break;
 805	case I2C_SMBUS_I2C_BLOCK_DATA:
 806		if (read_length > I2C_SMBUS_BLOCK_MAX) {
 807			ret = -EINVAL;
 808			goto power_normal;
 809		}
 810
 811		memcpy(data->block + 1, buf, read_length);
 812		break;
 813	case I2C_SMBUS_BLOCK_DATA:
 814		if (read_length > I2C_SMBUS_BLOCK_MAX) {
 815			ret = -EPROTO;
 816			goto power_normal;
 817		}
 818
 819		memcpy(data->block, buf, read_length);
 820		break;
 821	}
 822
 823	ret = 0;
 824power_normal:
 825	hid_hw_power(hdev, PM_HINT_NORMAL);
 826	hid_dbg(hdev, "transfer finished: %d\n", ret);
 827	return ret;
 828}
 829
 830static u32 cp2112_functionality(struct i2c_adapter *adap)
 831{
 832	return I2C_FUNC_I2C |
 833		I2C_FUNC_SMBUS_BYTE |
 834		I2C_FUNC_SMBUS_BYTE_DATA |
 835		I2C_FUNC_SMBUS_WORD_DATA |
 836		I2C_FUNC_SMBUS_BLOCK_DATA |
 837		I2C_FUNC_SMBUS_I2C_BLOCK |
 838		I2C_FUNC_SMBUS_PROC_CALL |
 839		I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 840}
 841
 842static const struct i2c_algorithm smbus_algorithm = {
 843	.master_xfer	= cp2112_i2c_xfer,
 844	.smbus_xfer	= cp2112_xfer,
 845	.functionality	= cp2112_functionality,
 846};
 847
 848static int cp2112_get_usb_config(struct hid_device *hdev,
 849				 struct cp2112_usb_config_report *cfg)
 850{
 851	int ret;
 852
 853	ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 854			     HID_FEATURE_REPORT);
 855	if (ret != sizeof(*cfg)) {
 856		hid_err(hdev, "error reading usb config: %d\n", ret);
 857		if (ret < 0)
 858			return ret;
 859		return -EIO;
 860	}
 861
 862	return 0;
 863}
 864
 865static int cp2112_set_usb_config(struct hid_device *hdev,
 866				 struct cp2112_usb_config_report *cfg)
 867{
 868	int ret;
 869
 870	if (WARN_ON(cfg->report != CP2112_USB_CONFIG))
 871		return -EINVAL;
 872
 873	ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 874				HID_FEATURE_REPORT);
 875	if (ret != sizeof(*cfg)) {
 876		hid_err(hdev, "error writing usb config: %d\n", ret);
 877		if (ret < 0)
 878			return ret;
 879		return -EIO;
 880	}
 881
 882	return 0;
 883}
 884
 885static void chmod_sysfs_attrs(struct hid_device *hdev);
 886
 887#define CP2112_CONFIG_ATTR(name, store, format, ...) \
 888static ssize_t name##_store(struct device *kdev, \
 889			    struct device_attribute *attr, const char *buf, \
 890			    size_t count) \
 891{ \
 892	struct hid_device *hdev = to_hid_device(kdev); \
 893	struct cp2112_usb_config_report cfg; \
 894	int ret = cp2112_get_usb_config(hdev, &cfg); \
 895	if (ret) \
 896		return ret; \
 897	store; \
 898	ret = cp2112_set_usb_config(hdev, &cfg); \
 899	if (ret) \
 900		return ret; \
 901	chmod_sysfs_attrs(hdev); \
 902	return count; \
 903} \
 904static ssize_t name##_show(struct device *kdev, \
 905			   struct device_attribute *attr, char *buf) \
 906{ \
 907	struct hid_device *hdev = to_hid_device(kdev); \
 908	struct cp2112_usb_config_report cfg; \
 909	int ret = cp2112_get_usb_config(hdev, &cfg); \
 910	if (ret) \
 911		return ret; \
 912	return sysfs_emit(buf, format, ##__VA_ARGS__); \
 913} \
 914static DEVICE_ATTR_RW(name);
 915
 916CP2112_CONFIG_ATTR(vendor_id, ({
 917	u16 vid;
 918
 919	if (sscanf(buf, "%hi", &vid) != 1)
 920		return -EINVAL;
 921
 922	cfg.vid = cpu_to_le16(vid);
 923	cfg.mask = 0x01;
 924}), "0x%04x\n", le16_to_cpu(cfg.vid));
 925
 926CP2112_CONFIG_ATTR(product_id, ({
 927	u16 pid;
 928
 929	if (sscanf(buf, "%hi", &pid) != 1)
 930		return -EINVAL;
 931
 932	cfg.pid = cpu_to_le16(pid);
 933	cfg.mask = 0x02;
 934}), "0x%04x\n", le16_to_cpu(cfg.pid));
 935
 936CP2112_CONFIG_ATTR(max_power, ({
 937	int mA;
 938
 939	if (sscanf(buf, "%i", &mA) != 1)
 940		return -EINVAL;
 941
 942	cfg.max_power = (mA + 1) / 2;
 943	cfg.mask = 0x04;
 944}), "%u mA\n", cfg.max_power * 2);
 945
 946CP2112_CONFIG_ATTR(power_mode, ({
 947	if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 948		return -EINVAL;
 949
 950	cfg.mask = 0x08;
 951}), "%u\n", cfg.power_mode);
 952
 953CP2112_CONFIG_ATTR(release_version, ({
 954	if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 955	    != 2)
 956		return -EINVAL;
 957
 958	cfg.mask = 0x10;
 959}), "%u.%u\n", cfg.release_major, cfg.release_minor);
 960
 961#undef CP2112_CONFIG_ATTR
 962
 963static ssize_t pstr_store(struct device *kdev, struct device_attribute *kattr,
 964			  const char *buf, size_t count, int number)
 965{
 966	struct hid_device *hdev = to_hid_device(kdev);
 967	struct cp2112_string_report report;
 968	int ret;
 969
 970	memset(&report, 0, sizeof(report));
 971
 972	ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 973			      report.string, ARRAY_SIZE(report.string));
 974	report.report = number;
 975	report.length = ret * sizeof(report.string[0]) + 2;
 976	report.type = USB_DT_STRING;
 977
 978	ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 979				HID_FEATURE_REPORT);
 980	if (ret != report.length + 1) {
 981		hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 982			ret);
 983		if (ret < 0)
 984			return ret;
 985		return -EIO;
 986	}
 987
 988	chmod_sysfs_attrs(hdev);
 989	return count;
 990}
 991
 992static ssize_t pstr_show(struct device *kdev, struct device_attribute *kattr,
 993			 char *buf, int number)
 994{
 995	struct hid_device *hdev = to_hid_device(kdev);
 996	struct cp2112_string_report report;
 997	u8 length;
 998	int ret;
 999
1000	ret = cp2112_hid_get(hdev, number, (u8 *)&report.contents,
1001			     sizeof(report.contents), HID_FEATURE_REPORT);
1002	if (ret < 3) {
1003		hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
1004			ret);
1005		if (ret < 0)
1006			return ret;
1007		return -EIO;
1008	}
1009
1010	if (report.length < 2) {
1011		hid_err(hdev, "invalid %s string length: %d\n",
1012			kattr->attr.name, report.length);
1013		return -EIO;
1014	}
1015
1016	length = report.length > ret - 1 ? ret - 1 : report.length;
1017	length = (length - 2) / sizeof(report.string[0]);
1018	ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1019			      PAGE_SIZE - 1);
1020	buf[ret++] = '\n';
1021	return ret;
1022}
1023
1024#define CP2112_PSTR_ATTR(name, _report) \
1025static ssize_t name##_store(struct device *kdev, struct device_attribute *kattr, \
1026			    const char *buf, size_t count) \
1027{ \
1028	return pstr_store(kdev, kattr, buf, count, _report); \
1029} \
1030static ssize_t name##_show(struct device *kdev, struct device_attribute *kattr, char *buf) \
1031{ \
1032	return pstr_show(kdev, kattr, buf, _report); \
1033} \
1034static DEVICE_ATTR_RW(name);
1035
1036CP2112_PSTR_ATTR(manufacturer,	CP2112_MANUFACTURER_STRING);
1037CP2112_PSTR_ATTR(product,	CP2112_PRODUCT_STRING);
1038CP2112_PSTR_ATTR(serial,	CP2112_SERIAL_STRING);
1039
1040#undef CP2112_PSTR_ATTR
1041
1042static const struct attribute_group cp2112_attr_group = {
1043	.attrs = (struct attribute *[]){
1044		&dev_attr_vendor_id.attr,
1045		&dev_attr_product_id.attr,
1046		&dev_attr_max_power.attr,
1047		&dev_attr_power_mode.attr,
1048		&dev_attr_release_version.attr,
1049		&dev_attr_manufacturer.attr,
1050		&dev_attr_product.attr,
1051		&dev_attr_serial.attr,
1052		NULL
1053	}
1054};
1055
1056/* Chmoding our sysfs attributes is simply a way to expose which fields in the
1057 * PROM have already been programmed. We do not depend on this preventing
1058 * writing to these attributes since the CP2112 will simply ignore writes to
1059 * already-programmed fields. This is why there is no sense in fixing this
1060 * racy behaviour.
1061 */
1062static void chmod_sysfs_attrs(struct hid_device *hdev)
1063{
1064	struct attribute **attr;
1065	u8 buf[2];
1066	int ret;
1067
1068	ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1069			     HID_FEATURE_REPORT);
1070	if (ret != sizeof(buf)) {
1071		hid_err(hdev, "error reading lock byte: %d\n", ret);
1072		return;
1073	}
1074
1075	for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1076		umode_t mode = (buf[1] & 1) ? 0644 : 0444;
1077		ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1078		if (ret < 0)
1079			hid_err(hdev, "error chmoding sysfs file %s\n",
1080				(*attr)->name);
1081		buf[1] >>= 1;
1082	}
1083}
1084
1085static void cp2112_gpio_irq_ack(struct irq_data *d)
1086{
1087}
1088
1089static void cp2112_gpio_irq_mask(struct irq_data *d)
1090{
1091	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1092	struct cp2112_device *dev = gpiochip_get_data(gc);
1093	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1094
1095	__clear_bit(hwirq, &dev->irq_mask);
1096	gpiochip_disable_irq(gc, hwirq);
1097}
1098
1099static void cp2112_gpio_irq_unmask(struct irq_data *d)
1100{
1101	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1102	struct cp2112_device *dev = gpiochip_get_data(gc);
1103	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1104
1105	gpiochip_enable_irq(gc, hwirq);
1106	__set_bit(hwirq, &dev->irq_mask);
1107}
1108
1109static void cp2112_gpio_poll_callback(struct work_struct *work)
1110{
1111	struct cp2112_device *dev = container_of(work, struct cp2112_device,
1112						 gpio_poll_worker.work);
1113	u8 gpio_mask;
1114	u32 irq_type;
1115	int irq, virq, ret;
1116
1117	ret = cp2112_gpio_get_all(&dev->gc);
1118	if (ret == -ENODEV) /* the hardware has been disconnected */
1119		return;
1120	if (ret < 0)
1121		goto exit;
1122
1123	gpio_mask = ret;
1124	for_each_set_bit(virq, &dev->irq_mask, CP2112_GPIO_MAX_GPIO) {
1125		irq = irq_find_mapping(dev->gc.irq.domain, virq);
1126		if (!irq)
1127			continue;
1128
1129		irq_type = irq_get_trigger_type(irq);
1130		if (!irq_type)
1131			continue;
1132
1133		if (gpio_mask & BIT(virq)) {
1134			/* Level High */
1135
1136			if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1137				handle_nested_irq(irq);
1138
1139			if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1140			    !(dev->gpio_prev_state & BIT(virq)))
1141				handle_nested_irq(irq);
1142		} else {
1143			/* Level Low */
1144
1145			if (irq_type & IRQ_TYPE_LEVEL_LOW)
1146				handle_nested_irq(irq);
1147
1148			if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1149			    (dev->gpio_prev_state & BIT(virq)))
1150				handle_nested_irq(irq);
1151		}
1152	}
1153
1154	dev->gpio_prev_state = gpio_mask;
1155
1156exit:
1157	if (dev->gpio_poll)
1158		schedule_delayed_work(&dev->gpio_poll_worker, 10);
1159}
1160
1161
1162static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1163{
1164	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1165	struct cp2112_device *dev = gpiochip_get_data(gc);
1166
1167	if (!dev->gpio_poll) {
1168		dev->gpio_poll = true;
1169		schedule_delayed_work(&dev->gpio_poll_worker, 0);
1170	}
1171
1172	cp2112_gpio_irq_unmask(d);
1173	return 0;
1174}
1175
1176static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1177{
1178	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1179	struct cp2112_device *dev = gpiochip_get_data(gc);
1180
1181	cp2112_gpio_irq_mask(d);
1182
1183	if (!dev->irq_mask) {
1184		dev->gpio_poll = false;
1185		cancel_delayed_work_sync(&dev->gpio_poll_worker);
1186	}
1187}
1188
1189static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1190{
1191	return 0;
1192}
1193
1194static const struct irq_chip cp2112_gpio_irqchip = {
1195	.name = "cp2112-gpio",
1196	.irq_startup = cp2112_gpio_irq_startup,
1197	.irq_shutdown = cp2112_gpio_irq_shutdown,
1198	.irq_ack = cp2112_gpio_irq_ack,
1199	.irq_mask = cp2112_gpio_irq_mask,
1200	.irq_unmask = cp2112_gpio_irq_unmask,
1201	.irq_set_type = cp2112_gpio_irq_type,
1202	.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
1203	GPIOCHIP_IRQ_RESOURCE_HELPERS,
1204};
1205
1206static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1207{
1208	struct cp2112_device *dev;
1209	u8 buf[3];
1210	struct cp2112_smbus_config_report config;
1211	struct gpio_irq_chip *girq;
1212	int ret;
1213
1214	dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1215	if (!dev)
1216		return -ENOMEM;
1217
1218	dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1219					  GFP_KERNEL);
1220	if (!dev->in_out_buffer)
1221		return -ENOMEM;
1222
1223	ret = devm_mutex_init(&hdev->dev, &dev->lock);
1224	if (ret) {
1225		hid_err(hdev, "mutex init failed\n");
1226		return ret;
1227	}
1228
1229	ret = hid_parse(hdev);
1230	if (ret) {
1231		hid_err(hdev, "parse failed\n");
1232		return ret;
1233	}
1234
1235	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1236	if (ret) {
1237		hid_err(hdev, "hw start failed\n");
1238		return ret;
1239	}
1240
1241	ret = hid_hw_open(hdev);
1242	if (ret) {
1243		hid_err(hdev, "hw open failed\n");
1244		goto err_hid_stop;
1245	}
1246
1247	ret = hid_hw_power(hdev, PM_HINT_FULLON);
1248	if (ret < 0) {
1249		hid_err(hdev, "power management error: %d\n", ret);
1250		goto err_hid_close;
1251	}
1252
1253	ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1254			     HID_FEATURE_REPORT);
1255	if (ret != sizeof(buf)) {
1256		hid_err(hdev, "error requesting version\n");
1257		if (ret >= 0)
1258			ret = -EIO;
1259		goto err_power_normal;
1260	}
1261
1262	hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1263		 buf[1], buf[2]);
1264
1265	ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1266			     sizeof(config), HID_FEATURE_REPORT);
1267	if (ret != sizeof(config)) {
1268		hid_err(hdev, "error requesting SMBus config\n");
1269		if (ret >= 0)
1270			ret = -EIO;
1271		goto err_power_normal;
1272	}
1273
1274	config.retry_time = cpu_to_be16(1);
1275
1276	ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1277				HID_FEATURE_REPORT);
1278	if (ret != sizeof(config)) {
1279		hid_err(hdev, "error setting SMBus config\n");
1280		if (ret >= 0)
1281			ret = -EIO;
1282		goto err_power_normal;
1283	}
1284
1285	hid_set_drvdata(hdev, (void *)dev);
1286	dev->hdev		= hdev;
1287	dev->adap.owner		= THIS_MODULE;
1288	dev->adap.class		= I2C_CLASS_HWMON;
1289	dev->adap.algo		= &smbus_algorithm;
1290	dev->adap.algo_data	= dev;
1291	dev->adap.dev.parent	= &hdev->dev;
1292	snprintf(dev->adap.name, sizeof(dev->adap.name),
1293		 "CP2112 SMBus Bridge on hidraw%d",
1294		 ((struct hidraw *)hdev->hidraw)->minor);
1295	dev->hwversion = buf[2];
1296	init_waitqueue_head(&dev->wait);
1297
1298	hid_device_io_start(hdev);
1299	ret = i2c_add_adapter(&dev->adap);
1300	hid_device_io_stop(hdev);
1301
1302	if (ret) {
1303		hid_err(hdev, "error registering i2c adapter\n");
1304		goto err_power_normal;
1305	}
1306
1307	hid_dbg(hdev, "adapter registered\n");
1308
1309	dev->gc.label			= "cp2112_gpio";
1310	dev->gc.direction_input		= cp2112_gpio_direction_input;
1311	dev->gc.direction_output	= cp2112_gpio_direction_output;
1312	dev->gc.set			= cp2112_gpio_set;
1313	dev->gc.get			= cp2112_gpio_get;
1314	dev->gc.base			= -1;
1315	dev->gc.ngpio			= CP2112_GPIO_MAX_GPIO;
1316	dev->gc.can_sleep		= 1;
1317	dev->gc.parent			= &hdev->dev;
1318
1319	girq = &dev->gc.irq;
1320	gpio_irq_chip_set_chip(girq, &cp2112_gpio_irqchip);
1321	/* The event comes from the outside so no parent handler */
1322	girq->parent_handler = NULL;
1323	girq->num_parents = 0;
1324	girq->parents = NULL;
1325	girq->default_type = IRQ_TYPE_NONE;
1326	girq->handler = handle_simple_irq;
1327	girq->threaded = true;
1328
1329	INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1330
1331	ret = gpiochip_add_data(&dev->gc, dev);
1332	if (ret < 0) {
1333		hid_err(hdev, "error registering gpio chip\n");
1334		goto err_free_i2c;
1335	}
1336
1337	ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1338	if (ret < 0) {
1339		hid_err(hdev, "error creating sysfs attrs\n");
1340		goto err_gpiochip_remove;
1341	}
1342
1343	chmod_sysfs_attrs(hdev);
1344	hid_hw_power(hdev, PM_HINT_NORMAL);
1345
1346	return ret;
1347
1348err_gpiochip_remove:
1349	gpiochip_remove(&dev->gc);
1350err_free_i2c:
1351	i2c_del_adapter(&dev->adap);
1352err_power_normal:
1353	hid_hw_power(hdev, PM_HINT_NORMAL);
1354err_hid_close:
1355	hid_hw_close(hdev);
1356err_hid_stop:
1357	hid_hw_stop(hdev);
1358	return ret;
1359}
1360
1361static void cp2112_remove(struct hid_device *hdev)
1362{
1363	struct cp2112_device *dev = hid_get_drvdata(hdev);
1364
1365	sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1366	i2c_del_adapter(&dev->adap);
1367
1368	if (dev->gpio_poll) {
1369		dev->gpio_poll = false;
1370		cancel_delayed_work_sync(&dev->gpio_poll_worker);
1371	}
1372
1373	gpiochip_remove(&dev->gc);
1374	/* i2c_del_adapter has finished removing all i2c devices from our
1375	 * adapter. Well behaved devices should no longer call our cp2112_xfer
1376	 * and should have waited for any pending calls to finish. It has also
1377	 * waited for device_unregister(&adap->dev) to complete. Therefore we
1378	 * can safely free our struct cp2112_device.
1379	 */
1380	hid_hw_close(hdev);
1381	hid_hw_stop(hdev);
1382}
1383
1384static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1385			    u8 *data, int size)
1386{
1387	struct cp2112_device *dev = hid_get_drvdata(hdev);
1388	struct cp2112_xfer_status_report *xfer = (void *)data;
1389
1390	switch (data[0]) {
1391	case CP2112_TRANSFER_STATUS_RESPONSE:
1392		hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1393			xfer->status0, xfer->status1,
1394			be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1395
1396		switch (xfer->status0) {
1397		case STATUS0_IDLE:
1398			dev->xfer_status = -EAGAIN;
1399			break;
1400		case STATUS0_BUSY:
1401			dev->xfer_status = -EBUSY;
1402			break;
1403		case STATUS0_COMPLETE:
1404			dev->xfer_status = be16_to_cpu(xfer->length);
1405			break;
1406		case STATUS0_ERROR:
1407			switch (xfer->status1) {
1408			case STATUS1_TIMEOUT_NACK:
1409			case STATUS1_TIMEOUT_BUS:
1410				dev->xfer_status = -ETIMEDOUT;
1411				break;
1412			default:
1413				dev->xfer_status = -EIO;
1414				break;
1415			}
1416			break;
1417		default:
1418			dev->xfer_status = -EINVAL;
1419			break;
1420		}
1421
1422		atomic_set(&dev->xfer_avail, 1);
1423		break;
1424	case CP2112_DATA_READ_RESPONSE:
1425		hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1426
1427		dev->read_length = data[2];
1428		if (dev->read_length > sizeof(dev->read_data))
1429			dev->read_length = sizeof(dev->read_data);
1430
1431		memcpy(dev->read_data, &data[3], dev->read_length);
1432		atomic_set(&dev->read_avail, 1);
1433		break;
1434	default:
1435		hid_err(hdev, "unknown report\n");
1436
1437		return 0;
1438	}
1439
1440	wake_up_interruptible(&dev->wait);
1441	return 1;
1442}
1443
1444static struct hid_driver cp2112_driver = {
1445	.name		= "cp2112",
1446	.id_table	= cp2112_devices,
1447	.probe		= cp2112_probe,
1448	.remove		= cp2112_remove,
1449	.raw_event	= cp2112_raw_event,
1450};
1451
1452module_hid_driver(cp2112_driver);
1453MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1454MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1455MODULE_LICENSE("GPL");
1456