1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * hid-ft260.c - FTDI FT260 USB HID to I2C host bridge 4 * 5 * Copyright (c) 2021, Michael Zaidman <michaelz@xsightlabs.com> 6 * 7 * Data Sheet: 8 * https://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT260.pdf 9 */ 10 11 #include "hid-ids.h" 12 #include <linux/hidraw.h> 13 #include <linux/i2c.h> 14 #include <linux/module.h> 15 #include <linux/usb.h> 16 17 #ifdef DEBUG 18 static int ft260_debug = 1; 19 #else 20 static int ft260_debug; 21 #endif 22 module_param_named(debug, ft260_debug, int, 0600); 23 MODULE_PARM_DESC(debug, "Toggle FT260 debugging messages"); 24 25 #define ft260_dbg(format, arg...) \ 26 do { \ 27 if (ft260_debug) \ 28 pr_info("%s: " format, __func__, ##arg); \ 29 } while (0) 30 31 #define FT260_REPORT_MAX_LENGTH (64) 32 #define FT260_I2C_DATA_REPORT_ID(len) (FT260_I2C_REPORT_MIN + (len - 1) / 4) 33 /* 34 * The input report format assigns 62 bytes for the data payload, but ft260 35 * returns 60 and 2 in two separate transactions. To minimize transfer time 36 * in reading chunks mode, set the maximum read payload length to 60 bytes. 37 */ 38 #define FT260_RD_DATA_MAX (60) 39 #define FT260_WR_DATA_MAX (60) 40 41 /* 42 * Device interface configuration. 43 * The FT260 has 2 interfaces that are controlled by DCNF0 and DCNF1 pins. 44 * First implementes USB HID to I2C bridge function and 45 * second - USB HID to UART bridge function. 46 */ 47 enum { 48 FT260_MODE_ALL = 0x00, 49 FT260_MODE_I2C = 0x01, 50 FT260_MODE_UART = 0x02, 51 FT260_MODE_BOTH = 0x03, 52 }; 53 54 /* Control pipe */ 55 enum { 56 FT260_GET_RQST_TYPE = 0xA1, 57 FT260_GET_REPORT = 0x01, 58 FT260_SET_RQST_TYPE = 0x21, 59 FT260_SET_REPORT = 0x09, 60 FT260_FEATURE = 0x03, 61 }; 62 63 /* Report IDs / Feature In */ 64 enum { 65 FT260_CHIP_VERSION = 0xA0, 66 FT260_SYSTEM_SETTINGS = 0xA1, 67 FT260_I2C_STATUS = 0xC0, 68 FT260_I2C_READ_REQ = 0xC2, 69 FT260_I2C_REPORT_MIN = 0xD0, 70 FT260_I2C_REPORT_MAX = 0xDE, 71 FT260_GPIO = 0xB0, 72 FT260_UART_INTERRUPT_STATUS = 0xB1, 73 FT260_UART_STATUS = 0xE0, 74 FT260_UART_RI_DCD_STATUS = 0xE1, 75 FT260_UART_REPORT = 0xF0, 76 }; 77 78 /* Feature Out */ 79 enum { 80 FT260_SET_CLOCK = 0x01, 81 FT260_SET_I2C_MODE = 0x02, 82 FT260_SET_UART_MODE = 0x03, 83 FT260_ENABLE_INTERRUPT = 0x05, 84 FT260_SELECT_GPIO2_FUNC = 0x06, 85 FT260_ENABLE_UART_DCD_RI = 0x07, 86 FT260_SELECT_GPIOA_FUNC = 0x08, 87 FT260_SELECT_GPIOG_FUNC = 0x09, 88 FT260_SET_INTERRUPT_TRIGGER = 0x0A, 89 FT260_SET_SUSPEND_OUT_POLAR = 0x0B, 90 FT260_ENABLE_UART_RI_WAKEUP = 0x0C, 91 FT260_SET_UART_RI_WAKEUP_CFG = 0x0D, 92 FT260_SET_I2C_RESET = 0x20, 93 FT260_SET_I2C_CLOCK_SPEED = 0x22, 94 FT260_SET_UART_RESET = 0x40, 95 FT260_SET_UART_CONFIG = 0x41, 96 FT260_SET_UART_BAUD_RATE = 0x42, 97 FT260_SET_UART_DATA_BIT = 0x43, 98 FT260_SET_UART_PARITY = 0x44, 99 FT260_SET_UART_STOP_BIT = 0x45, 100 FT260_SET_UART_BREAKING = 0x46, 101 FT260_SET_UART_XON_XOFF = 0x49, 102 }; 103 104 /* Response codes in I2C status report */ 105 enum { 106 FT260_I2C_STATUS_SUCCESS = 0x00, 107 FT260_I2C_STATUS_CTRL_BUSY = 0x01, 108 FT260_I2C_STATUS_ERROR = 0x02, 109 FT260_I2C_STATUS_ADDR_NO_ACK = 0x04, 110 FT260_I2C_STATUS_DATA_NO_ACK = 0x08, 111 FT260_I2C_STATUS_ARBITR_LOST = 0x10, 112 FT260_I2C_STATUS_CTRL_IDLE = 0x20, 113 FT260_I2C_STATUS_BUS_BUSY = 0x40, 114 }; 115 116 /* I2C Conditions flags */ 117 enum { 118 FT260_FLAG_NONE = 0x00, 119 FT260_FLAG_START = 0x02, 120 FT260_FLAG_START_REPEATED = 0x03, 121 FT260_FLAG_STOP = 0x04, 122 FT260_FLAG_START_STOP = 0x06, 123 FT260_FLAG_START_STOP_REPEATED = 0x07, 124 }; 125 126 #define FT260_SET_REQUEST_VALUE(report_id) ((FT260_FEATURE << 8) | report_id) 127 128 /* Feature In reports */ 129 130 struct ft260_get_chip_version_report { 131 u8 report; /* FT260_CHIP_VERSION */ 132 u8 chip_code[4]; /* FTDI chip identification code */ 133 u8 reserved[8]; 134 } __packed; 135 136 struct ft260_get_system_status_report { 137 u8 report; /* FT260_SYSTEM_SETTINGS */ 138 u8 chip_mode; /* DCNF0 and DCNF1 status, bits 0-1 */ 139 u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */ 140 u8 suspend_status; /* 0 - not suspended, 1 - suspended */ 141 u8 pwren_status; /* 0 - FT260 is not ready, 1 - ready */ 142 u8 i2c_enable; /* 0 - disabled, 1 - enabled */ 143 u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */ 144 /* 3 - XON_XOFF, 4 - No flow control */ 145 u8 hid_over_i2c_en; /* 0 - disabled, 1 - enabled */ 146 u8 gpio2_function; /* 0 - GPIO, 1 - SUSPOUT, */ 147 /* 2 - PWREN, 4 - TX_LED */ 148 u8 gpioA_function; /* 0 - GPIO, 3 - TX_ACTIVE, 4 - TX_LED */ 149 u8 gpioG_function; /* 0 - GPIO, 2 - PWREN, */ 150 /* 5 - RX_LED, 6 - BCD_DET */ 151 u8 suspend_out_pol; /* 0 - active-high, 1 - active-low */ 152 u8 enable_wakeup_int; /* 0 - disabled, 1 - enabled */ 153 u8 intr_cond; /* Interrupt trigger conditions */ 154 u8 power_saving_en; /* 0 - disabled, 1 - enabled */ 155 u8 reserved[10]; 156 } __packed; 157 158 struct ft260_get_i2c_status_report { 159 u8 report; /* FT260_I2C_STATUS */ 160 u8 bus_status; /* I2C bus status */ 161 __le16 clock; /* I2C bus clock in range 60-3400 KHz */ 162 u8 reserved; 163 } __packed; 164 165 /* Feature Out reports */ 166 167 struct ft260_set_system_clock_report { 168 u8 report; /* FT260_SYSTEM_SETTINGS */ 169 u8 request; /* FT260_SET_CLOCK */ 170 u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */ 171 } __packed; 172 173 struct ft260_set_i2c_mode_report { 174 u8 report; /* FT260_SYSTEM_SETTINGS */ 175 u8 request; /* FT260_SET_I2C_MODE */ 176 u8 i2c_enable; /* 0 - disabled, 1 - enabled */ 177 } __packed; 178 179 struct ft260_set_uart_mode_report { 180 u8 report; /* FT260_SYSTEM_SETTINGS */ 181 u8 request; /* FT260_SET_UART_MODE */ 182 u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */ 183 /* 3 - XON_XOFF, 4 - No flow control */ 184 } __packed; 185 186 struct ft260_set_i2c_reset_report { 187 u8 report; /* FT260_SYSTEM_SETTINGS */ 188 u8 request; /* FT260_SET_I2C_RESET */ 189 } __packed; 190 191 struct ft260_set_i2c_speed_report { 192 u8 report; /* FT260_SYSTEM_SETTINGS */ 193 u8 request; /* FT260_SET_I2C_CLOCK_SPEED */ 194 __le16 clock; /* I2C bus clock in range 60-3400 KHz */ 195 } __packed; 196 197 /* Data transfer reports */ 198 199 struct ft260_i2c_write_request_report { 200 u8 report; /* FT260_I2C_REPORT */ 201 u8 address; /* 7-bit I2C address */ 202 u8 flag; /* I2C transaction condition */ 203 u8 length; /* data payload length */ 204 u8 data[60]; /* data payload */ 205 } __packed; 206 207 struct ft260_i2c_read_request_report { 208 u8 report; /* FT260_I2C_READ_REQ */ 209 u8 address; /* 7-bit I2C address */ 210 u8 flag; /* I2C transaction condition */ 211 __le16 length; /* data payload length */ 212 } __packed; 213 214 struct ft260_i2c_input_report { 215 u8 report; /* FT260_I2C_REPORT */ 216 u8 length; /* data payload length */ 217 u8 data[2]; /* data payload */ 218 } __packed; 219 220 static const struct hid_device_id ft260_devices[] = { 221 { HID_USB_DEVICE(USB_VENDOR_ID_FUTURE_TECHNOLOGY, 222 USB_DEVICE_ID_FT260) }, 223 { /* END OF LIST */ } 224 }; 225 MODULE_DEVICE_TABLE(hid, ft260_devices); 226 227 struct ft260_device { 228 struct i2c_adapter adap; 229 struct hid_device *hdev; 230 struct completion wait; 231 struct mutex lock; 232 u8 write_buf[FT260_REPORT_MAX_LENGTH]; 233 u8 *read_buf; 234 u16 read_idx; 235 u16 read_len; 236 u16 clock; 237 }; 238 239 static int ft260_hid_feature_report_get(struct hid_device *hdev, 240 unsigned char report_id, u8 *data, 241 size_t len) 242 { 243 u8 *buf; 244 int ret; 245 246 buf = kmalloc(len, GFP_KERNEL); 247 if (!buf) 248 return -ENOMEM; 249 250 ret = hid_hw_raw_request(hdev, report_id, buf, len, HID_FEATURE_REPORT, 251 HID_REQ_GET_REPORT); 252 memcpy(data, buf, len); 253 kfree(buf); 254 return ret; 255 } 256 257 static int ft260_hid_feature_report_set(struct hid_device *hdev, u8 *data, 258 size_t len) 259 { 260 u8 *buf; 261 int ret; 262 263 buf = kmemdup(data, len, GFP_KERNEL); 264 if (!buf) 265 return -ENOMEM; 266 267 buf[0] = FT260_SYSTEM_SETTINGS; 268 269 ret = hid_hw_raw_request(hdev, buf[0], buf, len, HID_FEATURE_REPORT, 270 HID_REQ_SET_REPORT); 271 272 kfree(buf); 273 return ret; 274 } 275 276 static int ft260_i2c_reset(struct hid_device *hdev) 277 { 278 struct ft260_set_i2c_reset_report report; 279 int ret; 280 281 report.request = FT260_SET_I2C_RESET; 282 283 ret = ft260_hid_feature_report_set(hdev, (u8 *)&report, sizeof(report)); 284 if (ret < 0) { 285 hid_err(hdev, "failed to reset I2C controller: %d\n", ret); 286 return ret; 287 } 288 289 ft260_dbg("done\n"); 290 return ret; 291 } 292 293 static int ft260_xfer_status(struct ft260_device *dev) 294 { 295 struct hid_device *hdev = dev->hdev; 296 struct ft260_get_i2c_status_report report; 297 int ret; 298 299 ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, 300 (u8 *)&report, sizeof(report)); 301 if (ret < 0) { 302 hid_err(hdev, "failed to retrieve status: %d\n", ret); 303 return ret; 304 } 305 306 dev->clock = le16_to_cpu(report.clock); 307 ft260_dbg("bus_status %#02x, clock %u\n", report.bus_status, 308 dev->clock); 309 310 if (report.bus_status & FT260_I2C_STATUS_CTRL_BUSY) 311 return -EAGAIN; 312 313 if (report.bus_status & FT260_I2C_STATUS_BUS_BUSY) 314 return -EBUSY; 315 316 if (report.bus_status & FT260_I2C_STATUS_ERROR) 317 return -EIO; 318 319 ret = -EIO; 320 321 if (report.bus_status & FT260_I2C_STATUS_ADDR_NO_ACK) 322 ft260_dbg("unacknowledged address\n"); 323 324 if (report.bus_status & FT260_I2C_STATUS_DATA_NO_ACK) 325 ft260_dbg("unacknowledged data\n"); 326 327 if (report.bus_status & FT260_I2C_STATUS_ARBITR_LOST) 328 ft260_dbg("arbitration loss\n"); 329 330 if (report.bus_status & FT260_I2C_STATUS_CTRL_IDLE) 331 ret = 0; 332 333 return ret; 334 } 335 336 static int ft260_hid_output_report(struct hid_device *hdev, u8 *data, 337 size_t len) 338 { 339 u8 *buf; 340 int ret; 341 342 buf = kmemdup(data, len, GFP_KERNEL); 343 if (!buf) 344 return -ENOMEM; 345 346 ret = hid_hw_output_report(hdev, buf, len); 347 348 kfree(buf); 349 return ret; 350 } 351 352 static int ft260_hid_output_report_check_status(struct ft260_device *dev, 353 u8 *data, int len) 354 { 355 int ret, usec, try = 3; 356 struct hid_device *hdev = dev->hdev; 357 358 ret = ft260_hid_output_report(hdev, data, len); 359 if (ret < 0) { 360 hid_err(hdev, "%s: failed to start transfer, ret %d\n", 361 __func__, ret); 362 ft260_i2c_reset(hdev); 363 return ret; 364 } 365 366 /* transfer time = 1 / clock(KHz) * 10 bits * bytes */ 367 usec = 10000 / dev->clock * len; 368 usleep_range(usec, usec + 100); 369 ft260_dbg("wait %d usec, len %d\n", usec, len); 370 do { 371 ret = ft260_xfer_status(dev); 372 if (ret != -EAGAIN) 373 break; 374 } while (--try); 375 376 if (ret == 0 || ret == -EBUSY) 377 return 0; 378 379 ft260_i2c_reset(hdev); 380 return -EIO; 381 } 382 383 static int ft260_i2c_write(struct ft260_device *dev, u8 addr, u8 *data, 384 int data_len, u8 flag) 385 { 386 int len, ret, idx = 0; 387 struct hid_device *hdev = dev->hdev; 388 struct ft260_i2c_write_request_report *rep = 389 (struct ft260_i2c_write_request_report *)dev->write_buf; 390 391 do { 392 if (data_len <= FT260_WR_DATA_MAX) 393 len = data_len; 394 else 395 len = FT260_WR_DATA_MAX; 396 397 rep->report = FT260_I2C_DATA_REPORT_ID(len); 398 rep->address = addr; 399 rep->length = len; 400 rep->flag = flag; 401 402 memcpy(rep->data, &data[idx], len); 403 404 ft260_dbg("rep %#02x addr %#02x off %d len %d d[0] %#02x\n", 405 rep->report, addr, idx, len, data[0]); 406 407 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, 408 len + 4); 409 if (ret < 0) { 410 hid_err(hdev, "%s: failed to start transfer, ret %d\n", 411 __func__, ret); 412 return ret; 413 } 414 415 data_len -= len; 416 idx += len; 417 418 } while (data_len > 0); 419 420 return 0; 421 } 422 423 static int ft260_smbus_write(struct ft260_device *dev, u8 addr, u8 cmd, 424 u8 *data, u8 data_len, u8 flag) 425 { 426 int ret = 0; 427 int len = 4; 428 429 struct ft260_i2c_write_request_report *rep = 430 (struct ft260_i2c_write_request_report *)dev->write_buf; 431 432 rep->address = addr; 433 rep->data[0] = cmd; 434 rep->length = data_len + 1; 435 rep->flag = flag; 436 len += rep->length; 437 438 rep->report = FT260_I2C_DATA_REPORT_ID(len); 439 440 if (data_len > 0) 441 memcpy(&rep->data[1], data, data_len); 442 443 ft260_dbg("rep %#02x addr %#02x cmd %#02x datlen %d replen %d\n", 444 rep->report, addr, cmd, rep->length, len); 445 446 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, len); 447 448 return ret; 449 } 450 451 static int ft260_i2c_read(struct ft260_device *dev, u8 addr, u8 *data, 452 u16 len, u8 flag) 453 { 454 struct ft260_i2c_read_request_report rep; 455 struct hid_device *hdev = dev->hdev; 456 int timeout; 457 int ret; 458 459 if (len > FT260_RD_DATA_MAX) { 460 hid_err(hdev, "%s: unsupported rd len: %d\n", __func__, len); 461 return -EINVAL; 462 } 463 464 dev->read_idx = 0; 465 dev->read_buf = data; 466 dev->read_len = len; 467 468 rep.report = FT260_I2C_READ_REQ; 469 rep.length = cpu_to_le16(len); 470 rep.address = addr; 471 rep.flag = flag; 472 473 ft260_dbg("rep %#02x addr %#02x len %d\n", rep.report, rep.address, 474 rep.length); 475 476 reinit_completion(&dev->wait); 477 478 ret = ft260_hid_output_report(hdev, (u8 *)&rep, sizeof(rep)); 479 if (ret < 0) { 480 hid_err(hdev, "%s: failed to start transaction, ret %d\n", 481 __func__, ret); 482 return ret; 483 } 484 485 timeout = msecs_to_jiffies(5000); 486 if (!wait_for_completion_timeout(&dev->wait, timeout)) { 487 ft260_i2c_reset(hdev); 488 return -ETIMEDOUT; 489 } 490 491 ret = ft260_xfer_status(dev); 492 if (ret == 0) 493 return 0; 494 495 ft260_i2c_reset(hdev); 496 return -EIO; 497 } 498 499 /* 500 * A random read operation is implemented as a dummy write operation, followed 501 * by a current address read operation. The dummy write operation is used to 502 * load the target byte address into the current byte address counter, from 503 * which the subsequent current address read operation then reads. 504 */ 505 static int ft260_i2c_write_read(struct ft260_device *dev, struct i2c_msg *msgs) 506 { 507 int len, ret; 508 u16 left_len = msgs[1].len; 509 u8 *read_buf = msgs[1].buf; 510 u8 addr = msgs[0].addr; 511 u16 read_off = 0; 512 struct hid_device *hdev = dev->hdev; 513 514 if (msgs[0].len > 2) { 515 hid_err(hdev, "%s: unsupported wr len: %d\n", __func__, 516 msgs[0].len); 517 return -EOPNOTSUPP; 518 } 519 520 memcpy(&read_off, msgs[0].buf, msgs[0].len); 521 522 do { 523 if (left_len <= FT260_RD_DATA_MAX) 524 len = left_len; 525 else 526 len = FT260_RD_DATA_MAX; 527 528 ft260_dbg("read_off %#x left_len %d len %d\n", read_off, 529 left_len, len); 530 531 ret = ft260_i2c_write(dev, addr, (u8 *)&read_off, msgs[0].len, 532 FT260_FLAG_START); 533 if (ret < 0) 534 return ret; 535 536 ret = ft260_i2c_read(dev, addr, read_buf, len, 537 FT260_FLAG_START_STOP); 538 if (ret < 0) 539 return ret; 540 541 left_len -= len; 542 read_buf += len; 543 read_off += len; 544 545 } while (left_len > 0); 546 547 return 0; 548 } 549 550 static int ft260_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 551 int num) 552 { 553 int ret; 554 struct ft260_device *dev = i2c_get_adapdata(adapter); 555 struct hid_device *hdev = dev->hdev; 556 557 mutex_lock(&dev->lock); 558 559 ret = hid_hw_power(hdev, PM_HINT_FULLON); 560 if (ret < 0) { 561 hid_err(hdev, "failed to enter FULLON power mode: %d\n", ret); 562 mutex_unlock(&dev->lock); 563 return ret; 564 } 565 566 if (num == 1) { 567 if (msgs->flags & I2C_M_RD) 568 ret = ft260_i2c_read(dev, msgs->addr, msgs->buf, 569 msgs->len, FT260_FLAG_START_STOP); 570 else 571 ret = ft260_i2c_write(dev, msgs->addr, msgs->buf, 572 msgs->len, FT260_FLAG_START_STOP); 573 if (ret < 0) 574 goto i2c_exit; 575 576 } else { 577 /* Combined write then read message */ 578 ret = ft260_i2c_write_read(dev, msgs); 579 if (ret < 0) 580 goto i2c_exit; 581 } 582 583 ret = num; 584 i2c_exit: 585 hid_hw_power(hdev, PM_HINT_NORMAL); 586 mutex_unlock(&dev->lock); 587 return ret; 588 } 589 590 static int ft260_smbus_xfer(struct i2c_adapter *adapter, u16 addr, u16 flags, 591 char read_write, u8 cmd, int size, 592 union i2c_smbus_data *data) 593 { 594 int ret; 595 struct ft260_device *dev = i2c_get_adapdata(adapter); 596 struct hid_device *hdev = dev->hdev; 597 598 ft260_dbg("smbus size %d\n", size); 599 600 mutex_lock(&dev->lock); 601 602 ret = hid_hw_power(hdev, PM_HINT_FULLON); 603 if (ret < 0) { 604 hid_err(hdev, "power management error: %d\n", ret); 605 mutex_unlock(&dev->lock); 606 return ret; 607 } 608 609 switch (size) { 610 case I2C_SMBUS_QUICK: 611 if (read_write == I2C_SMBUS_READ) 612 ret = ft260_i2c_read(dev, addr, &data->byte, 0, 613 FT260_FLAG_START_STOP); 614 else 615 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 616 FT260_FLAG_START_STOP); 617 break; 618 case I2C_SMBUS_BYTE: 619 if (read_write == I2C_SMBUS_READ) 620 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 621 FT260_FLAG_START_STOP); 622 else 623 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 624 FT260_FLAG_START_STOP); 625 break; 626 case I2C_SMBUS_BYTE_DATA: 627 if (read_write == I2C_SMBUS_READ) { 628 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 629 FT260_FLAG_START); 630 if (ret) 631 goto smbus_exit; 632 633 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 634 FT260_FLAG_START_STOP_REPEATED); 635 } else { 636 ret = ft260_smbus_write(dev, addr, cmd, &data->byte, 1, 637 FT260_FLAG_START_STOP); 638 } 639 break; 640 case I2C_SMBUS_WORD_DATA: 641 if (read_write == I2C_SMBUS_READ) { 642 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 643 FT260_FLAG_START); 644 if (ret) 645 goto smbus_exit; 646 647 ret = ft260_i2c_read(dev, addr, (u8 *)&data->word, 2, 648 FT260_FLAG_START_STOP_REPEATED); 649 } else { 650 ret = ft260_smbus_write(dev, addr, cmd, 651 (u8 *)&data->word, 2, 652 FT260_FLAG_START_STOP); 653 } 654 break; 655 case I2C_SMBUS_BLOCK_DATA: 656 if (read_write == I2C_SMBUS_READ) { 657 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 658 FT260_FLAG_START); 659 if (ret) 660 goto smbus_exit; 661 662 ret = ft260_i2c_read(dev, addr, data->block, 663 data->block[0] + 1, 664 FT260_FLAG_START_STOP_REPEATED); 665 } else { 666 ret = ft260_smbus_write(dev, addr, cmd, data->block, 667 data->block[0] + 1, 668 FT260_FLAG_START_STOP); 669 } 670 break; 671 case I2C_SMBUS_I2C_BLOCK_DATA: 672 if (read_write == I2C_SMBUS_READ) { 673 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 674 FT260_FLAG_START); 675 if (ret) 676 goto smbus_exit; 677 678 ret = ft260_i2c_read(dev, addr, data->block + 1, 679 data->block[0], 680 FT260_FLAG_START_STOP_REPEATED); 681 } else { 682 ret = ft260_smbus_write(dev, addr, cmd, data->block + 1, 683 data->block[0], 684 FT260_FLAG_START_STOP); 685 } 686 break; 687 default: 688 hid_err(hdev, "unsupported smbus transaction size %d\n", size); 689 ret = -EOPNOTSUPP; 690 } 691 692 smbus_exit: 693 hid_hw_power(hdev, PM_HINT_NORMAL); 694 mutex_unlock(&dev->lock); 695 return ret; 696 } 697 698 static u32 ft260_functionality(struct i2c_adapter *adap) 699 { 700 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_QUICK | 701 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 702 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; 703 } 704 705 static const struct i2c_adapter_quirks ft260_i2c_quirks = { 706 .flags = I2C_AQ_COMB_WRITE_THEN_READ, 707 .max_comb_1st_msg_len = 2, 708 }; 709 710 static const struct i2c_algorithm ft260_i2c_algo = { 711 .master_xfer = ft260_i2c_xfer, 712 .smbus_xfer = ft260_smbus_xfer, 713 .functionality = ft260_functionality, 714 }; 715 716 static int ft260_get_system_config(struct hid_device *hdev, 717 struct ft260_get_system_status_report *cfg) 718 { 719 int ret; 720 int len = sizeof(struct ft260_get_system_status_report); 721 722 ret = ft260_hid_feature_report_get(hdev, FT260_SYSTEM_SETTINGS, 723 (u8 *)cfg, len); 724 if (ret != len) { 725 hid_err(hdev, "failed to retrieve system status\n"); 726 if (ret >= 0) 727 return -EIO; 728 } 729 return 0; 730 } 731 732 static int ft260_is_interface_enabled(struct hid_device *hdev) 733 { 734 struct ft260_get_system_status_report cfg; 735 struct usb_interface *usbif = to_usb_interface(hdev->dev.parent); 736 int interface = usbif->cur_altsetting->desc.bInterfaceNumber; 737 int ret; 738 739 ret = ft260_get_system_config(hdev, &cfg); 740 if (ret) 741 return ret; 742 743 ft260_dbg("interface: 0x%02x\n", interface); 744 ft260_dbg("chip mode: 0x%02x\n", cfg.chip_mode); 745 ft260_dbg("clock_ctl: 0x%02x\n", cfg.clock_ctl); 746 ft260_dbg("i2c_enable: 0x%02x\n", cfg.i2c_enable); 747 ft260_dbg("uart_mode: 0x%02x\n", cfg.uart_mode); 748 749 switch (cfg.chip_mode) { 750 case FT260_MODE_ALL: 751 case FT260_MODE_BOTH: 752 if (interface == 1) { 753 hid_info(hdev, "uart interface is not supported\n"); 754 return 0; 755 } 756 ret = 1; 757 break; 758 case FT260_MODE_UART: 759 if (interface == 0) { 760 hid_info(hdev, "uart is unsupported on interface 0\n"); 761 ret = 0; 762 } 763 break; 764 case FT260_MODE_I2C: 765 if (interface == 1) { 766 hid_info(hdev, "i2c is unsupported on interface 1\n"); 767 ret = 0; 768 } 769 break; 770 } 771 return ret; 772 } 773 774 static int ft260_byte_show(struct hid_device *hdev, int id, u8 *cfg, int len, 775 u8 *field, u8 *buf) 776 { 777 int ret; 778 779 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 780 if (ret != len && ret >= 0) 781 return -EIO; 782 783 return scnprintf(buf, PAGE_SIZE, "%hi\n", *field); 784 } 785 786 static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len, 787 u16 *field, u8 *buf) 788 { 789 int ret; 790 791 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 792 if (ret != len && ret >= 0) 793 return -EIO; 794 795 return scnprintf(buf, PAGE_SIZE, "%hi\n", le16_to_cpu(*field)); 796 } 797 798 #define FT260_ATTR_SHOW(name, reptype, id, type, func) \ 799 static ssize_t name##_show(struct device *kdev, \ 800 struct device_attribute *attr, char *buf) \ 801 { \ 802 struct reptype rep; \ 803 struct hid_device *hdev = to_hid_device(kdev); \ 804 type *field = &rep.name; \ 805 int len = sizeof(rep); \ 806 \ 807 return func(hdev, id, (u8 *)&rep, len, field, buf); \ 808 } 809 810 #define FT260_SSTAT_ATTR_SHOW(name) \ 811 FT260_ATTR_SHOW(name, ft260_get_system_status_report, \ 812 FT260_SYSTEM_SETTINGS, u8, ft260_byte_show) 813 814 #define FT260_I2CST_ATTR_SHOW(name) \ 815 FT260_ATTR_SHOW(name, ft260_get_i2c_status_report, \ 816 FT260_I2C_STATUS, u16, ft260_word_show) 817 818 #define FT260_ATTR_STORE(name, reptype, id, req, type, func) \ 819 static ssize_t name##_store(struct device *kdev, \ 820 struct device_attribute *attr, \ 821 const char *buf, size_t count) \ 822 { \ 823 struct reptype rep; \ 824 struct hid_device *hdev = to_hid_device(kdev); \ 825 type name; \ 826 int ret; \ 827 \ 828 if (!func(buf, 10, &name)) { \ 829 rep.name = name; \ 830 rep.report = id; \ 831 rep.request = req; \ 832 ret = ft260_hid_feature_report_set(hdev, (u8 *)&rep, \ 833 sizeof(rep)); \ 834 if (!ret) \ 835 ret = count; \ 836 } else { \ 837 ret = -EINVAL; \ 838 } \ 839 return ret; \ 840 } 841 842 #define FT260_BYTE_ATTR_STORE(name, reptype, req) \ 843 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 844 u8, kstrtou8) 845 846 #define FT260_WORD_ATTR_STORE(name, reptype, req) \ 847 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 848 u16, kstrtou16) 849 850 FT260_SSTAT_ATTR_SHOW(chip_mode); 851 static DEVICE_ATTR_RO(chip_mode); 852 853 FT260_SSTAT_ATTR_SHOW(pwren_status); 854 static DEVICE_ATTR_RO(pwren_status); 855 856 FT260_SSTAT_ATTR_SHOW(suspend_status); 857 static DEVICE_ATTR_RO(suspend_status); 858 859 FT260_SSTAT_ATTR_SHOW(hid_over_i2c_en); 860 static DEVICE_ATTR_RO(hid_over_i2c_en); 861 862 FT260_SSTAT_ATTR_SHOW(power_saving_en); 863 static DEVICE_ATTR_RO(power_saving_en); 864 865 FT260_SSTAT_ATTR_SHOW(i2c_enable); 866 FT260_BYTE_ATTR_STORE(i2c_enable, ft260_set_i2c_mode_report, 867 FT260_SET_I2C_MODE); 868 static DEVICE_ATTR_RW(i2c_enable); 869 870 FT260_SSTAT_ATTR_SHOW(uart_mode); 871 FT260_BYTE_ATTR_STORE(uart_mode, ft260_set_uart_mode_report, 872 FT260_SET_UART_MODE); 873 static DEVICE_ATTR_RW(uart_mode); 874 875 FT260_SSTAT_ATTR_SHOW(clock_ctl); 876 FT260_BYTE_ATTR_STORE(clock_ctl, ft260_set_system_clock_report, 877 FT260_SET_CLOCK); 878 static DEVICE_ATTR_RW(clock_ctl); 879 880 FT260_I2CST_ATTR_SHOW(clock); 881 FT260_WORD_ATTR_STORE(clock, ft260_set_i2c_speed_report, 882 FT260_SET_I2C_CLOCK_SPEED); 883 static DEVICE_ATTR_RW(clock); 884 885 static ssize_t i2c_reset_store(struct device *kdev, 886 struct device_attribute *attr, const char *buf, 887 size_t count) 888 { 889 struct hid_device *hdev = to_hid_device(kdev); 890 int ret = ft260_i2c_reset(hdev); 891 892 if (ret) 893 return ret; 894 return count; 895 } 896 static DEVICE_ATTR_WO(i2c_reset); 897 898 static const struct attribute_group ft260_attr_group = { 899 .attrs = (struct attribute *[]) { 900 &dev_attr_chip_mode.attr, 901 &dev_attr_pwren_status.attr, 902 &dev_attr_suspend_status.attr, 903 &dev_attr_hid_over_i2c_en.attr, 904 &dev_attr_power_saving_en.attr, 905 &dev_attr_i2c_enable.attr, 906 &dev_attr_uart_mode.attr, 907 &dev_attr_clock_ctl.attr, 908 &dev_attr_i2c_reset.attr, 909 &dev_attr_clock.attr, 910 NULL 911 } 912 }; 913 914 static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) 915 { 916 struct ft260_device *dev; 917 struct ft260_get_chip_version_report version; 918 int ret; 919 920 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL); 921 if (!dev) 922 return -ENOMEM; 923 924 ret = hid_parse(hdev); 925 if (ret) { 926 hid_err(hdev, "failed to parse HID\n"); 927 return ret; 928 } 929 930 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW); 931 if (ret) { 932 hid_err(hdev, "failed to start HID HW\n"); 933 return ret; 934 } 935 936 ret = hid_hw_open(hdev); 937 if (ret) { 938 hid_err(hdev, "failed to open HID HW\n"); 939 goto err_hid_stop; 940 } 941 942 ret = ft260_hid_feature_report_get(hdev, FT260_CHIP_VERSION, 943 (u8 *)&version, sizeof(version)); 944 if (ret != sizeof(version)) { 945 hid_err(hdev, "failed to retrieve chip version\n"); 946 if (ret >= 0) 947 ret = -EIO; 948 goto err_hid_close; 949 } 950 951 hid_info(hdev, "chip code: %02x%02x %02x%02x\n", 952 version.chip_code[0], version.chip_code[1], 953 version.chip_code[2], version.chip_code[3]); 954 955 ret = ft260_is_interface_enabled(hdev); 956 if (ret <= 0) 957 goto err_hid_close; 958 959 hid_set_drvdata(hdev, dev); 960 dev->hdev = hdev; 961 dev->adap.owner = THIS_MODULE; 962 dev->adap.class = I2C_CLASS_HWMON; 963 dev->adap.algo = &ft260_i2c_algo; 964 dev->adap.quirks = &ft260_i2c_quirks; 965 dev->adap.dev.parent = &hdev->dev; 966 snprintf(dev->adap.name, sizeof(dev->adap.name), 967 "FT260 usb-i2c bridge on hidraw%d", 968 ((struct hidraw *)hdev->hidraw)->minor); 969 970 mutex_init(&dev->lock); 971 init_completion(&dev->wait); 972 973 ret = i2c_add_adapter(&dev->adap); 974 if (ret) { 975 hid_err(hdev, "failed to add i2c adapter\n"); 976 goto err_hid_close; 977 } 978 979 i2c_set_adapdata(&dev->adap, dev); 980 981 ret = sysfs_create_group(&hdev->dev.kobj, &ft260_attr_group); 982 if (ret < 0) { 983 hid_err(hdev, "failed to create sysfs attrs\n"); 984 goto err_i2c_free; 985 } 986 987 ret = ft260_xfer_status(dev); 988 if (ret) 989 ft260_i2c_reset(hdev); 990 991 return 0; 992 993 err_i2c_free: 994 i2c_del_adapter(&dev->adap); 995 err_hid_close: 996 hid_hw_close(hdev); 997 err_hid_stop: 998 hid_hw_stop(hdev); 999 return ret; 1000 } 1001 1002 static void ft260_remove(struct hid_device *hdev) 1003 { 1004 int ret; 1005 struct ft260_device *dev = hid_get_drvdata(hdev); 1006 1007 ret = ft260_is_interface_enabled(hdev); 1008 if (ret <= 0) 1009 return; 1010 1011 sysfs_remove_group(&hdev->dev.kobj, &ft260_attr_group); 1012 i2c_del_adapter(&dev->adap); 1013 1014 hid_hw_close(hdev); 1015 hid_hw_stop(hdev); 1016 } 1017 1018 static int ft260_raw_event(struct hid_device *hdev, struct hid_report *report, 1019 u8 *data, int size) 1020 { 1021 struct ft260_device *dev = hid_get_drvdata(hdev); 1022 struct ft260_i2c_input_report *xfer = (void *)data; 1023 1024 if (xfer->report >= FT260_I2C_REPORT_MIN && 1025 xfer->report <= FT260_I2C_REPORT_MAX) { 1026 ft260_dbg("i2c resp: rep %#02x len %d\n", xfer->report, 1027 xfer->length); 1028 1029 memcpy(&dev->read_buf[dev->read_idx], &xfer->data, 1030 xfer->length); 1031 dev->read_idx += xfer->length; 1032 1033 if (dev->read_idx == dev->read_len) 1034 complete(&dev->wait); 1035 1036 } else { 1037 hid_err(hdev, "unknown report: %#02x\n", xfer->report); 1038 return 0; 1039 } 1040 return 1; 1041 } 1042 1043 static struct hid_driver ft260_driver = { 1044 .name = "ft260", 1045 .id_table = ft260_devices, 1046 .probe = ft260_probe, 1047 .remove = ft260_remove, 1048 .raw_event = ft260_raw_event, 1049 }; 1050 1051 module_hid_driver(ft260_driver); 1052 MODULE_DESCRIPTION("FTDI FT260 USB HID to I2C host bridge"); 1053 MODULE_AUTHOR("Michael Zaidman <michael.zaidman@gmail.com>"); 1054 MODULE_LICENSE("GPL v2"); 1055