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 #define FT260_WAKEUP_NEEDED_AFTER_MS (4800) /* 5s minus 200ms margin */ 35 36 /* 37 * The ft260 input report format defines 62 bytes for the data payload, but 38 * when requested 62 bytes, the controller returns 60 and 2 in separate input 39 * reports. To achieve better performance with the multi-report read data 40 * transfers, we set the maximum read payload length to a multiple of 60. 41 * With a 100 kHz I2C clock, one 240 bytes read takes about 1/27 second, 42 * which is excessive; On the other hand, some higher layer drivers like at24 43 * or optoe limit the i2c reads to 128 bytes. To not block other drivers out 44 * of I2C for potentially troublesome amounts of time, we select the maximum 45 * read payload length to be 180 bytes. 46 */ 47 #define FT260_RD_DATA_MAX (180) 48 #define FT260_WR_DATA_MAX (60) 49 50 /* 51 * Device interface configuration. 52 * The FT260 has 2 interfaces that are controlled by DCNF0 and DCNF1 pins. 53 * First implementes USB HID to I2C bridge function and 54 * second - USB HID to UART bridge function. 55 */ 56 enum { 57 FT260_MODE_ALL = 0x00, 58 FT260_MODE_I2C = 0x01, 59 FT260_MODE_UART = 0x02, 60 FT260_MODE_BOTH = 0x03, 61 }; 62 63 /* Control pipe */ 64 enum { 65 FT260_GET_RQST_TYPE = 0xA1, 66 FT260_GET_REPORT = 0x01, 67 FT260_SET_RQST_TYPE = 0x21, 68 FT260_SET_REPORT = 0x09, 69 FT260_FEATURE = 0x03, 70 }; 71 72 /* Report IDs / Feature In */ 73 enum { 74 FT260_CHIP_VERSION = 0xA0, 75 FT260_SYSTEM_SETTINGS = 0xA1, 76 FT260_I2C_STATUS = 0xC0, 77 FT260_I2C_READ_REQ = 0xC2, 78 FT260_I2C_REPORT_MIN = 0xD0, 79 FT260_I2C_REPORT_MAX = 0xDE, 80 FT260_GPIO = 0xB0, 81 FT260_UART_INTERRUPT_STATUS = 0xB1, 82 FT260_UART_STATUS = 0xE0, 83 FT260_UART_RI_DCD_STATUS = 0xE1, 84 FT260_UART_REPORT = 0xF0, 85 }; 86 87 /* Feature Out */ 88 enum { 89 FT260_SET_CLOCK = 0x01, 90 FT260_SET_I2C_MODE = 0x02, 91 FT260_SET_UART_MODE = 0x03, 92 FT260_ENABLE_INTERRUPT = 0x05, 93 FT260_SELECT_GPIO2_FUNC = 0x06, 94 FT260_ENABLE_UART_DCD_RI = 0x07, 95 FT260_SELECT_GPIOA_FUNC = 0x08, 96 FT260_SELECT_GPIOG_FUNC = 0x09, 97 FT260_SET_INTERRUPT_TRIGGER = 0x0A, 98 FT260_SET_SUSPEND_OUT_POLAR = 0x0B, 99 FT260_ENABLE_UART_RI_WAKEUP = 0x0C, 100 FT260_SET_UART_RI_WAKEUP_CFG = 0x0D, 101 FT260_SET_I2C_RESET = 0x20, 102 FT260_SET_I2C_CLOCK_SPEED = 0x22, 103 FT260_SET_UART_RESET = 0x40, 104 FT260_SET_UART_CONFIG = 0x41, 105 FT260_SET_UART_BAUD_RATE = 0x42, 106 FT260_SET_UART_DATA_BIT = 0x43, 107 FT260_SET_UART_PARITY = 0x44, 108 FT260_SET_UART_STOP_BIT = 0x45, 109 FT260_SET_UART_BREAKING = 0x46, 110 FT260_SET_UART_XON_XOFF = 0x49, 111 }; 112 113 /* Response codes in I2C status report */ 114 enum { 115 FT260_I2C_STATUS_SUCCESS = 0x00, 116 FT260_I2C_STATUS_CTRL_BUSY = 0x01, 117 FT260_I2C_STATUS_ERROR = 0x02, 118 FT260_I2C_STATUS_ADDR_NO_ACK = 0x04, 119 FT260_I2C_STATUS_DATA_NO_ACK = 0x08, 120 FT260_I2C_STATUS_ARBITR_LOST = 0x10, 121 FT260_I2C_STATUS_CTRL_IDLE = 0x20, 122 FT260_I2C_STATUS_BUS_BUSY = 0x40, 123 }; 124 125 /* I2C Conditions flags */ 126 enum { 127 FT260_FLAG_NONE = 0x00, 128 FT260_FLAG_START = 0x02, 129 FT260_FLAG_START_REPEATED = 0x03, 130 FT260_FLAG_STOP = 0x04, 131 FT260_FLAG_START_STOP = 0x06, 132 FT260_FLAG_START_STOP_REPEATED = 0x07, 133 }; 134 135 #define FT260_SET_REQUEST_VALUE(report_id) ((FT260_FEATURE << 8) | report_id) 136 137 /* Feature In reports */ 138 139 struct ft260_get_chip_version_report { 140 u8 report; /* FT260_CHIP_VERSION */ 141 u8 chip_code[4]; /* FTDI chip identification code */ 142 u8 reserved[8]; 143 } __packed; 144 145 struct ft260_get_system_status_report { 146 u8 report; /* FT260_SYSTEM_SETTINGS */ 147 u8 chip_mode; /* DCNF0 and DCNF1 status, bits 0-1 */ 148 u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */ 149 u8 suspend_status; /* 0 - not suspended, 1 - suspended */ 150 u8 pwren_status; /* 0 - FT260 is not ready, 1 - ready */ 151 u8 i2c_enable; /* 0 - disabled, 1 - enabled */ 152 u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */ 153 /* 3 - XON_XOFF, 4 - No flow control */ 154 u8 hid_over_i2c_en; /* 0 - disabled, 1 - enabled */ 155 u8 gpio2_function; /* 0 - GPIO, 1 - SUSPOUT, */ 156 /* 2 - PWREN, 4 - TX_LED */ 157 u8 gpioA_function; /* 0 - GPIO, 3 - TX_ACTIVE, 4 - TX_LED */ 158 u8 gpioG_function; /* 0 - GPIO, 2 - PWREN, */ 159 /* 5 - RX_LED, 6 - BCD_DET */ 160 u8 suspend_out_pol; /* 0 - active-high, 1 - active-low */ 161 u8 enable_wakeup_int; /* 0 - disabled, 1 - enabled */ 162 u8 intr_cond; /* Interrupt trigger conditions */ 163 u8 power_saving_en; /* 0 - disabled, 1 - enabled */ 164 u8 reserved[10]; 165 } __packed; 166 167 struct ft260_get_i2c_status_report { 168 u8 report; /* FT260_I2C_STATUS */ 169 u8 bus_status; /* I2C bus status */ 170 __le16 clock; /* I2C bus clock in range 60-3400 KHz */ 171 u8 reserved; 172 } __packed; 173 174 /* Feature Out reports */ 175 176 struct ft260_set_system_clock_report { 177 u8 report; /* FT260_SYSTEM_SETTINGS */ 178 u8 request; /* FT260_SET_CLOCK */ 179 u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */ 180 } __packed; 181 182 struct ft260_set_i2c_mode_report { 183 u8 report; /* FT260_SYSTEM_SETTINGS */ 184 u8 request; /* FT260_SET_I2C_MODE */ 185 u8 i2c_enable; /* 0 - disabled, 1 - enabled */ 186 } __packed; 187 188 struct ft260_set_uart_mode_report { 189 u8 report; /* FT260_SYSTEM_SETTINGS */ 190 u8 request; /* FT260_SET_UART_MODE */ 191 u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */ 192 /* 3 - XON_XOFF, 4 - No flow control */ 193 } __packed; 194 195 struct ft260_set_i2c_reset_report { 196 u8 report; /* FT260_SYSTEM_SETTINGS */ 197 u8 request; /* FT260_SET_I2C_RESET */ 198 } __packed; 199 200 struct ft260_set_i2c_speed_report { 201 u8 report; /* FT260_SYSTEM_SETTINGS */ 202 u8 request; /* FT260_SET_I2C_CLOCK_SPEED */ 203 __le16 clock; /* I2C bus clock in range 60-3400 KHz */ 204 } __packed; 205 206 /* Data transfer reports */ 207 208 struct ft260_i2c_write_request_report { 209 u8 report; /* FT260_I2C_REPORT */ 210 u8 address; /* 7-bit I2C address */ 211 u8 flag; /* I2C transaction condition */ 212 u8 length; /* data payload length */ 213 u8 data[FT260_WR_DATA_MAX]; /* data payload */ 214 } __packed; 215 216 struct ft260_i2c_read_request_report { 217 u8 report; /* FT260_I2C_READ_REQ */ 218 u8 address; /* 7-bit I2C address */ 219 u8 flag; /* I2C transaction condition */ 220 __le16 length; /* data payload length */ 221 } __packed; 222 223 struct ft260_i2c_input_report { 224 u8 report; /* FT260_I2C_REPORT */ 225 u8 length; /* data payload length */ 226 u8 data[2]; /* data payload */ 227 } __packed; 228 229 static const struct hid_device_id ft260_devices[] = { 230 { HID_USB_DEVICE(USB_VENDOR_ID_FUTURE_TECHNOLOGY, 231 USB_DEVICE_ID_FT260) }, 232 { /* END OF LIST */ } 233 }; 234 MODULE_DEVICE_TABLE(hid, ft260_devices); 235 236 struct ft260_device { 237 struct i2c_adapter adap; 238 struct hid_device *hdev; 239 struct completion wait; 240 struct mutex lock; 241 u8 write_buf[FT260_REPORT_MAX_LENGTH]; 242 unsigned long need_wakeup_at; 243 u8 *read_buf; 244 u16 read_idx; 245 u16 read_len; 246 u16 clock; 247 }; 248 249 static int ft260_hid_feature_report_get(struct hid_device *hdev, 250 unsigned char report_id, u8 *data, 251 size_t len) 252 { 253 u8 *buf; 254 int ret; 255 256 buf = kmalloc(len, GFP_KERNEL); 257 if (!buf) 258 return -ENOMEM; 259 260 ret = hid_hw_raw_request(hdev, report_id, buf, len, HID_FEATURE_REPORT, 261 HID_REQ_GET_REPORT); 262 if (likely(ret == len)) 263 memcpy(data, buf, len); 264 else if (ret >= 0) 265 ret = -EIO; 266 kfree(buf); 267 return ret; 268 } 269 270 static int ft260_hid_feature_report_set(struct hid_device *hdev, u8 *data, 271 size_t len) 272 { 273 u8 *buf; 274 int ret; 275 276 buf = kmemdup(data, len, GFP_KERNEL); 277 if (!buf) 278 return -ENOMEM; 279 280 buf[0] = FT260_SYSTEM_SETTINGS; 281 282 ret = hid_hw_raw_request(hdev, buf[0], buf, len, HID_FEATURE_REPORT, 283 HID_REQ_SET_REPORT); 284 285 kfree(buf); 286 return ret; 287 } 288 289 static int ft260_i2c_reset(struct hid_device *hdev) 290 { 291 struct ft260_set_i2c_reset_report report; 292 int ret; 293 294 report.request = FT260_SET_I2C_RESET; 295 296 ret = ft260_hid_feature_report_set(hdev, (u8 *)&report, sizeof(report)); 297 if (ret < 0) { 298 hid_err(hdev, "failed to reset I2C controller: %d\n", ret); 299 return ret; 300 } 301 302 ft260_dbg("done\n"); 303 return ret; 304 } 305 306 static int ft260_xfer_status(struct ft260_device *dev) 307 { 308 struct hid_device *hdev = dev->hdev; 309 struct ft260_get_i2c_status_report report; 310 int ret; 311 312 if (time_is_before_jiffies(dev->need_wakeup_at)) { 313 ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, 314 (u8 *)&report, sizeof(report)); 315 if (unlikely(ret < 0)) { 316 hid_err(hdev, "failed to retrieve status: %d, no wakeup\n", 317 ret); 318 } else { 319 dev->need_wakeup_at = jiffies + 320 msecs_to_jiffies(FT260_WAKEUP_NEEDED_AFTER_MS); 321 ft260_dbg("bus_status %#02x, wakeup\n", 322 report.bus_status); 323 } 324 } 325 326 ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, 327 (u8 *)&report, sizeof(report)); 328 if (unlikely(ret < 0)) { 329 hid_err(hdev, "failed to retrieve status: %d\n", ret); 330 return ret; 331 } 332 333 dev->clock = le16_to_cpu(report.clock); 334 ft260_dbg("bus_status %#02x, clock %u\n", report.bus_status, 335 dev->clock); 336 337 if (report.bus_status & FT260_I2C_STATUS_CTRL_BUSY) 338 return -EAGAIN; 339 340 /* 341 * The error condition (bit 1) is a status bit reflecting any 342 * error conditions. When any of the bits 2, 3, or 4 are raised 343 * to 1, bit 1 is also set to 1. 344 */ 345 if (report.bus_status & FT260_I2C_STATUS_ERROR) { 346 hid_err(hdev, "i2c bus error: %#02x\n", report.bus_status); 347 return -EIO; 348 } 349 350 return 0; 351 } 352 353 static int ft260_hid_output_report(struct hid_device *hdev, u8 *data, 354 size_t len) 355 { 356 u8 *buf; 357 int ret; 358 359 buf = kmemdup(data, len, GFP_KERNEL); 360 if (!buf) 361 return -ENOMEM; 362 363 ret = hid_hw_output_report(hdev, buf, len); 364 365 kfree(buf); 366 return ret; 367 } 368 369 static int ft260_hid_output_report_check_status(struct ft260_device *dev, 370 u8 *data, int len) 371 { 372 int ret, usec, try = 100; 373 struct hid_device *hdev = dev->hdev; 374 375 ret = ft260_hid_output_report(hdev, data, len); 376 if (ret < 0) { 377 hid_err(hdev, "%s: failed to start transfer, ret %d\n", 378 __func__, ret); 379 ft260_i2c_reset(hdev); 380 return ret; 381 } 382 383 /* transfer time = 1 / clock(KHz) * 9 bits * bytes */ 384 usec = len * 9000 / dev->clock; 385 if (usec > 2000) { 386 usec -= 1500; 387 usleep_range(usec, usec + 100); 388 ft260_dbg("wait %d usec, len %d\n", usec, len); 389 } 390 391 do { 392 ret = ft260_xfer_status(dev); 393 if (ret != -EAGAIN) 394 break; 395 } while (--try); 396 397 if (ret == 0) 398 return 0; 399 400 ft260_i2c_reset(hdev); 401 return -EIO; 402 } 403 404 static int ft260_i2c_write(struct ft260_device *dev, u8 addr, u8 *data, 405 int len, u8 flag) 406 { 407 int ret, wr_len, idx = 0; 408 struct hid_device *hdev = dev->hdev; 409 struct ft260_i2c_write_request_report *rep = 410 (struct ft260_i2c_write_request_report *)dev->write_buf; 411 412 if (len < 1) 413 return -EINVAL; 414 415 rep->flag = FT260_FLAG_START; 416 417 do { 418 if (len <= FT260_WR_DATA_MAX) { 419 wr_len = len; 420 if (flag == FT260_FLAG_START_STOP) 421 rep->flag |= FT260_FLAG_STOP; 422 } else { 423 wr_len = FT260_WR_DATA_MAX; 424 } 425 426 rep->report = FT260_I2C_DATA_REPORT_ID(wr_len); 427 rep->address = addr; 428 rep->length = wr_len; 429 430 memcpy(rep->data, &data[idx], wr_len); 431 432 ft260_dbg("rep %#02x addr %#02x off %d len %d wlen %d flag %#x d[0] %#02x\n", 433 rep->report, addr, idx, len, wr_len, 434 rep->flag, data[0]); 435 436 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, 437 wr_len + 4); 438 if (ret < 0) { 439 hid_err(hdev, "%s: failed with %d\n", __func__, ret); 440 return ret; 441 } 442 443 len -= wr_len; 444 idx += wr_len; 445 rep->flag = 0; 446 447 } while (len > 0); 448 449 return 0; 450 } 451 452 static int ft260_smbus_write(struct ft260_device *dev, u8 addr, u8 cmd, 453 u8 *data, u8 data_len, u8 flag) 454 { 455 int ret = 0; 456 int len = 4; 457 458 struct ft260_i2c_write_request_report *rep = 459 (struct ft260_i2c_write_request_report *)dev->write_buf; 460 461 if (data_len >= sizeof(rep->data)) 462 return -EINVAL; 463 464 rep->address = addr; 465 rep->data[0] = cmd; 466 rep->length = data_len + 1; 467 rep->flag = flag; 468 len += rep->length; 469 470 rep->report = FT260_I2C_DATA_REPORT_ID(len); 471 472 if (data_len > 0) 473 memcpy(&rep->data[1], data, data_len); 474 475 ft260_dbg("rep %#02x addr %#02x cmd %#02x datlen %d replen %d\n", 476 rep->report, addr, cmd, rep->length, len); 477 478 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, len); 479 480 return ret; 481 } 482 483 static int ft260_i2c_read(struct ft260_device *dev, u8 addr, u8 *data, 484 u16 len, u8 flag) 485 { 486 u16 rd_len; 487 u16 rd_data_max = 60; 488 int timeout, ret = 0; 489 struct ft260_i2c_read_request_report rep; 490 struct hid_device *hdev = dev->hdev; 491 492 if ((flag & FT260_FLAG_START_REPEATED) == FT260_FLAG_START_REPEATED) 493 flag = FT260_FLAG_START_REPEATED; 494 else 495 flag = FT260_FLAG_START; 496 do { 497 if (len <= rd_data_max) { 498 rd_len = len; 499 flag |= FT260_FLAG_STOP; 500 } else { 501 rd_len = rd_data_max; 502 } 503 rd_data_max = FT260_RD_DATA_MAX; 504 505 rep.report = FT260_I2C_READ_REQ; 506 rep.length = cpu_to_le16(rd_len); 507 rep.address = addr; 508 rep.flag = flag; 509 510 ft260_dbg("rep %#02x addr %#02x len %d rlen %d flag %#x\n", 511 rep.report, rep.address, len, rd_len, flag); 512 513 reinit_completion(&dev->wait); 514 515 dev->read_idx = 0; 516 dev->read_buf = data; 517 dev->read_len = rd_len; 518 519 ret = ft260_hid_output_report(hdev, (u8 *)&rep, sizeof(rep)); 520 if (ret < 0) { 521 hid_err(hdev, "%s: failed with %d\n", __func__, ret); 522 goto ft260_i2c_read_exit; 523 } 524 525 timeout = msecs_to_jiffies(5000); 526 if (!wait_for_completion_timeout(&dev->wait, timeout)) { 527 ret = -ETIMEDOUT; 528 ft260_i2c_reset(hdev); 529 goto ft260_i2c_read_exit; 530 } 531 532 dev->read_buf = NULL; 533 534 ret = ft260_xfer_status(dev); 535 if (ret < 0) { 536 ret = -EIO; 537 ft260_i2c_reset(hdev); 538 goto ft260_i2c_read_exit; 539 } 540 541 len -= rd_len; 542 data += rd_len; 543 flag = 0; 544 545 } while (len > 0); 546 547 ft260_i2c_read_exit: 548 dev->read_buf = NULL; 549 return ret; 550 } 551 552 /* 553 * A random read operation is implemented as a dummy write operation, followed 554 * by a current address read operation. The dummy write operation is used to 555 * load the target byte address into the current byte address counter, from 556 * which the subsequent current address read operation then reads. 557 */ 558 static int ft260_i2c_write_read(struct ft260_device *dev, struct i2c_msg *msgs) 559 { 560 int ret; 561 int wr_len = msgs[0].len; 562 int rd_len = msgs[1].len; 563 struct hid_device *hdev = dev->hdev; 564 u8 addr = msgs[0].addr; 565 u16 read_off = 0; 566 567 if (wr_len > 2) { 568 hid_err(hdev, "%s: invalid wr_len: %d\n", __func__, wr_len); 569 return -EOPNOTSUPP; 570 } 571 572 if (ft260_debug) { 573 if (wr_len == 2) 574 read_off = be16_to_cpu(*(u16 *)msgs[0].buf); 575 else 576 read_off = *msgs[0].buf; 577 578 pr_info("%s: off %#x rlen %d wlen %d\n", __func__, 579 read_off, rd_len, wr_len); 580 } 581 582 ret = ft260_i2c_write(dev, addr, msgs[0].buf, wr_len, 583 FT260_FLAG_START); 584 if (ret < 0) 585 return ret; 586 587 ret = ft260_i2c_read(dev, addr, msgs[1].buf, rd_len, 588 FT260_FLAG_START_STOP_REPEATED); 589 if (ret < 0) 590 return ret; 591 592 return 0; 593 } 594 595 static int ft260_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 596 int num) 597 { 598 int ret; 599 struct ft260_device *dev = i2c_get_adapdata(adapter); 600 struct hid_device *hdev = dev->hdev; 601 602 mutex_lock(&dev->lock); 603 604 ret = hid_hw_power(hdev, PM_HINT_FULLON); 605 if (ret < 0) { 606 hid_err(hdev, "failed to enter FULLON power mode: %d\n", ret); 607 mutex_unlock(&dev->lock); 608 return ret; 609 } 610 611 if (num == 1) { 612 if (msgs->flags & I2C_M_RD) 613 ret = ft260_i2c_read(dev, msgs->addr, msgs->buf, 614 msgs->len, FT260_FLAG_START_STOP); 615 else 616 ret = ft260_i2c_write(dev, msgs->addr, msgs->buf, 617 msgs->len, FT260_FLAG_START_STOP); 618 if (ret < 0) 619 goto i2c_exit; 620 621 } else { 622 /* Combined write then read message */ 623 ret = ft260_i2c_write_read(dev, msgs); 624 if (ret < 0) 625 goto i2c_exit; 626 } 627 628 ret = num; 629 i2c_exit: 630 hid_hw_power(hdev, PM_HINT_NORMAL); 631 mutex_unlock(&dev->lock); 632 return ret; 633 } 634 635 static int ft260_smbus_xfer(struct i2c_adapter *adapter, u16 addr, u16 flags, 636 char read_write, u8 cmd, int size, 637 union i2c_smbus_data *data) 638 { 639 int ret; 640 struct ft260_device *dev = i2c_get_adapdata(adapter); 641 struct hid_device *hdev = dev->hdev; 642 643 ft260_dbg("smbus size %d\n", size); 644 645 mutex_lock(&dev->lock); 646 647 ret = hid_hw_power(hdev, PM_HINT_FULLON); 648 if (ret < 0) { 649 hid_err(hdev, "power management error: %d\n", ret); 650 mutex_unlock(&dev->lock); 651 return ret; 652 } 653 654 switch (size) { 655 case I2C_SMBUS_BYTE: 656 if (read_write == I2C_SMBUS_READ) 657 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 658 FT260_FLAG_START_STOP); 659 else 660 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 661 FT260_FLAG_START_STOP); 662 break; 663 case I2C_SMBUS_BYTE_DATA: 664 if (read_write == I2C_SMBUS_READ) { 665 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 666 FT260_FLAG_START); 667 if (ret) 668 goto smbus_exit; 669 670 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 671 FT260_FLAG_START_STOP_REPEATED); 672 } else { 673 ret = ft260_smbus_write(dev, addr, cmd, &data->byte, 1, 674 FT260_FLAG_START_STOP); 675 } 676 break; 677 case I2C_SMBUS_WORD_DATA: 678 if (read_write == I2C_SMBUS_READ) { 679 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 680 FT260_FLAG_START); 681 if (ret) 682 goto smbus_exit; 683 684 ret = ft260_i2c_read(dev, addr, (u8 *)&data->word, 2, 685 FT260_FLAG_START_STOP_REPEATED); 686 } else { 687 ret = ft260_smbus_write(dev, addr, cmd, 688 (u8 *)&data->word, 2, 689 FT260_FLAG_START_STOP); 690 } 691 break; 692 case I2C_SMBUS_BLOCK_DATA: 693 if (read_write == I2C_SMBUS_READ) { 694 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 695 FT260_FLAG_START); 696 if (ret) 697 goto smbus_exit; 698 699 ret = ft260_i2c_read(dev, addr, data->block, 700 data->block[0] + 1, 701 FT260_FLAG_START_STOP_REPEATED); 702 } else { 703 ret = ft260_smbus_write(dev, addr, cmd, data->block, 704 data->block[0] + 1, 705 FT260_FLAG_START_STOP); 706 } 707 break; 708 case I2C_SMBUS_I2C_BLOCK_DATA: 709 if (read_write == I2C_SMBUS_READ) { 710 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 711 FT260_FLAG_START); 712 if (ret) 713 goto smbus_exit; 714 715 ret = ft260_i2c_read(dev, addr, data->block + 1, 716 data->block[0], 717 FT260_FLAG_START_STOP_REPEATED); 718 } else { 719 ret = ft260_smbus_write(dev, addr, cmd, data->block + 1, 720 data->block[0], 721 FT260_FLAG_START_STOP); 722 } 723 break; 724 default: 725 hid_err(hdev, "unsupported smbus transaction size %d\n", size); 726 ret = -EOPNOTSUPP; 727 } 728 729 smbus_exit: 730 hid_hw_power(hdev, PM_HINT_NORMAL); 731 mutex_unlock(&dev->lock); 732 return ret; 733 } 734 735 static u32 ft260_functionality(struct i2c_adapter *adap) 736 { 737 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | 738 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 739 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; 740 } 741 742 static const struct i2c_adapter_quirks ft260_i2c_quirks = { 743 .flags = I2C_AQ_COMB_WRITE_THEN_READ, 744 .max_comb_1st_msg_len = 2, 745 }; 746 747 static const struct i2c_algorithm ft260_i2c_algo = { 748 .master_xfer = ft260_i2c_xfer, 749 .smbus_xfer = ft260_smbus_xfer, 750 .functionality = ft260_functionality, 751 }; 752 753 static int ft260_get_system_config(struct hid_device *hdev, 754 struct ft260_get_system_status_report *cfg) 755 { 756 int ret; 757 int len = sizeof(struct ft260_get_system_status_report); 758 759 ret = ft260_hid_feature_report_get(hdev, FT260_SYSTEM_SETTINGS, 760 (u8 *)cfg, len); 761 if (ret < 0) { 762 hid_err(hdev, "failed to retrieve system status\n"); 763 return ret; 764 } 765 return 0; 766 } 767 768 static int ft260_is_interface_enabled(struct hid_device *hdev) 769 { 770 struct ft260_get_system_status_report cfg; 771 struct usb_interface *usbif = to_usb_interface(hdev->dev.parent); 772 int interface = usbif->cur_altsetting->desc.bInterfaceNumber; 773 int ret; 774 775 ret = ft260_get_system_config(hdev, &cfg); 776 if (ret < 0) 777 return ret; 778 779 ft260_dbg("interface: 0x%02x\n", interface); 780 ft260_dbg("chip mode: 0x%02x\n", cfg.chip_mode); 781 ft260_dbg("clock_ctl: 0x%02x\n", cfg.clock_ctl); 782 ft260_dbg("i2c_enable: 0x%02x\n", cfg.i2c_enable); 783 ft260_dbg("uart_mode: 0x%02x\n", cfg.uart_mode); 784 785 switch (cfg.chip_mode) { 786 case FT260_MODE_ALL: 787 case FT260_MODE_BOTH: 788 if (interface == 1) 789 hid_info(hdev, "uart interface is not supported\n"); 790 else 791 ret = 1; 792 break; 793 case FT260_MODE_UART: 794 hid_info(hdev, "uart interface is not supported\n"); 795 break; 796 case FT260_MODE_I2C: 797 ret = 1; 798 break; 799 } 800 return ret; 801 } 802 803 static int ft260_byte_show(struct hid_device *hdev, int id, u8 *cfg, int len, 804 u8 *field, u8 *buf) 805 { 806 int ret; 807 808 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 809 if (ret < 0) 810 return ret; 811 812 return scnprintf(buf, PAGE_SIZE, "%d\n", *field); 813 } 814 815 static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len, 816 u16 *field, u8 *buf) 817 { 818 int ret; 819 820 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 821 if (ret < 0) 822 return ret; 823 824 return scnprintf(buf, PAGE_SIZE, "%d\n", le16_to_cpu(*field)); 825 } 826 827 #define FT260_ATTR_SHOW(name, reptype, id, type, func) \ 828 static ssize_t name##_show(struct device *kdev, \ 829 struct device_attribute *attr, char *buf) \ 830 { \ 831 struct reptype rep; \ 832 struct hid_device *hdev = to_hid_device(kdev); \ 833 type *field = &rep.name; \ 834 int len = sizeof(rep); \ 835 \ 836 return func(hdev, id, (u8 *)&rep, len, field, buf); \ 837 } 838 839 #define FT260_SSTAT_ATTR_SHOW(name) \ 840 FT260_ATTR_SHOW(name, ft260_get_system_status_report, \ 841 FT260_SYSTEM_SETTINGS, u8, ft260_byte_show) 842 843 #define FT260_I2CST_ATTR_SHOW(name) \ 844 FT260_ATTR_SHOW(name, ft260_get_i2c_status_report, \ 845 FT260_I2C_STATUS, u16, ft260_word_show) 846 847 #define FT260_ATTR_STORE(name, reptype, id, req, type, func) \ 848 static ssize_t name##_store(struct device *kdev, \ 849 struct device_attribute *attr, \ 850 const char *buf, size_t count) \ 851 { \ 852 struct reptype rep; \ 853 struct hid_device *hdev = to_hid_device(kdev); \ 854 type name; \ 855 int ret; \ 856 \ 857 if (!func(buf, 10, &name)) { \ 858 rep.name = name; \ 859 rep.report = id; \ 860 rep.request = req; \ 861 ret = ft260_hid_feature_report_set(hdev, (u8 *)&rep, \ 862 sizeof(rep)); \ 863 if (!ret) \ 864 ret = count; \ 865 } else { \ 866 ret = -EINVAL; \ 867 } \ 868 return ret; \ 869 } 870 871 #define FT260_BYTE_ATTR_STORE(name, reptype, req) \ 872 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 873 u8, kstrtou8) 874 875 #define FT260_WORD_ATTR_STORE(name, reptype, req) \ 876 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 877 u16, kstrtou16) 878 879 FT260_SSTAT_ATTR_SHOW(chip_mode); 880 static DEVICE_ATTR_RO(chip_mode); 881 882 FT260_SSTAT_ATTR_SHOW(pwren_status); 883 static DEVICE_ATTR_RO(pwren_status); 884 885 FT260_SSTAT_ATTR_SHOW(suspend_status); 886 static DEVICE_ATTR_RO(suspend_status); 887 888 FT260_SSTAT_ATTR_SHOW(hid_over_i2c_en); 889 static DEVICE_ATTR_RO(hid_over_i2c_en); 890 891 FT260_SSTAT_ATTR_SHOW(power_saving_en); 892 static DEVICE_ATTR_RO(power_saving_en); 893 894 FT260_SSTAT_ATTR_SHOW(i2c_enable); 895 FT260_BYTE_ATTR_STORE(i2c_enable, ft260_set_i2c_mode_report, 896 FT260_SET_I2C_MODE); 897 static DEVICE_ATTR_RW(i2c_enable); 898 899 FT260_SSTAT_ATTR_SHOW(uart_mode); 900 FT260_BYTE_ATTR_STORE(uart_mode, ft260_set_uart_mode_report, 901 FT260_SET_UART_MODE); 902 static DEVICE_ATTR_RW(uart_mode); 903 904 FT260_SSTAT_ATTR_SHOW(clock_ctl); 905 FT260_BYTE_ATTR_STORE(clock_ctl, ft260_set_system_clock_report, 906 FT260_SET_CLOCK); 907 static DEVICE_ATTR_RW(clock_ctl); 908 909 FT260_I2CST_ATTR_SHOW(clock); 910 FT260_WORD_ATTR_STORE(clock, ft260_set_i2c_speed_report, 911 FT260_SET_I2C_CLOCK_SPEED); 912 static DEVICE_ATTR_RW(clock); 913 914 static ssize_t i2c_reset_store(struct device *kdev, 915 struct device_attribute *attr, const char *buf, 916 size_t count) 917 { 918 struct hid_device *hdev = to_hid_device(kdev); 919 int ret = ft260_i2c_reset(hdev); 920 921 if (ret) 922 return ret; 923 return count; 924 } 925 static DEVICE_ATTR_WO(i2c_reset); 926 927 static const struct attribute_group ft260_attr_group = { 928 .attrs = (struct attribute *[]) { 929 &dev_attr_chip_mode.attr, 930 &dev_attr_pwren_status.attr, 931 &dev_attr_suspend_status.attr, 932 &dev_attr_hid_over_i2c_en.attr, 933 &dev_attr_power_saving_en.attr, 934 &dev_attr_i2c_enable.attr, 935 &dev_attr_uart_mode.attr, 936 &dev_attr_clock_ctl.attr, 937 &dev_attr_i2c_reset.attr, 938 &dev_attr_clock.attr, 939 NULL 940 } 941 }; 942 943 static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) 944 { 945 struct ft260_device *dev; 946 struct ft260_get_chip_version_report version; 947 int ret; 948 949 if (!hid_is_usb(hdev)) 950 return -EINVAL; 951 952 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL); 953 if (!dev) 954 return -ENOMEM; 955 956 ret = hid_parse(hdev); 957 if (ret) { 958 hid_err(hdev, "failed to parse HID\n"); 959 return ret; 960 } 961 962 ret = hid_hw_start(hdev, 0); 963 if (ret) { 964 hid_err(hdev, "failed to start HID HW\n"); 965 return ret; 966 } 967 968 ret = hid_hw_open(hdev); 969 if (ret) { 970 hid_err(hdev, "failed to open HID HW\n"); 971 goto err_hid_stop; 972 } 973 974 ret = ft260_hid_feature_report_get(hdev, FT260_CHIP_VERSION, 975 (u8 *)&version, sizeof(version)); 976 if (ret < 0) { 977 hid_err(hdev, "failed to retrieve chip version\n"); 978 goto err_hid_close; 979 } 980 981 hid_info(hdev, "chip code: %02x%02x %02x%02x\n", 982 version.chip_code[0], version.chip_code[1], 983 version.chip_code[2], version.chip_code[3]); 984 985 ret = ft260_is_interface_enabled(hdev); 986 if (ret <= 0) 987 goto err_hid_close; 988 989 hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", 990 hdev->version >> 8, hdev->version & 0xff, hdev->name, 991 hdev->phys); 992 993 hid_set_drvdata(hdev, dev); 994 dev->hdev = hdev; 995 dev->adap.owner = THIS_MODULE; 996 dev->adap.class = I2C_CLASS_HWMON; 997 dev->adap.algo = &ft260_i2c_algo; 998 dev->adap.quirks = &ft260_i2c_quirks; 999 dev->adap.dev.parent = &hdev->dev; 1000 snprintf(dev->adap.name, sizeof(dev->adap.name), 1001 "FT260 usb-i2c bridge"); 1002 1003 mutex_init(&dev->lock); 1004 init_completion(&dev->wait); 1005 1006 ret = ft260_xfer_status(dev); 1007 if (ret) 1008 ft260_i2c_reset(hdev); 1009 1010 i2c_set_adapdata(&dev->adap, dev); 1011 ret = i2c_add_adapter(&dev->adap); 1012 if (ret) { 1013 hid_err(hdev, "failed to add i2c adapter\n"); 1014 goto err_hid_close; 1015 } 1016 1017 ret = sysfs_create_group(&hdev->dev.kobj, &ft260_attr_group); 1018 if (ret < 0) { 1019 hid_err(hdev, "failed to create sysfs attrs\n"); 1020 goto err_i2c_free; 1021 } 1022 1023 return 0; 1024 1025 err_i2c_free: 1026 i2c_del_adapter(&dev->adap); 1027 err_hid_close: 1028 hid_hw_close(hdev); 1029 err_hid_stop: 1030 hid_hw_stop(hdev); 1031 return ret; 1032 } 1033 1034 static void ft260_remove(struct hid_device *hdev) 1035 { 1036 struct ft260_device *dev = hid_get_drvdata(hdev); 1037 1038 if (!dev) 1039 return; 1040 1041 sysfs_remove_group(&hdev->dev.kobj, &ft260_attr_group); 1042 i2c_del_adapter(&dev->adap); 1043 1044 hid_hw_close(hdev); 1045 hid_hw_stop(hdev); 1046 } 1047 1048 static int ft260_raw_event(struct hid_device *hdev, struct hid_report *report, 1049 u8 *data, int size) 1050 { 1051 struct ft260_device *dev = hid_get_drvdata(hdev); 1052 struct ft260_i2c_input_report *xfer = (void *)data; 1053 1054 if (xfer->report >= FT260_I2C_REPORT_MIN && 1055 xfer->report <= FT260_I2C_REPORT_MAX) { 1056 ft260_dbg("i2c resp: rep %#02x len %d\n", xfer->report, 1057 xfer->length); 1058 1059 if ((dev->read_buf == NULL) || 1060 (xfer->length > dev->read_len - dev->read_idx)) { 1061 hid_err(hdev, "unexpected report %#02x, length %d\n", 1062 xfer->report, xfer->length); 1063 return -1; 1064 } 1065 1066 memcpy(&dev->read_buf[dev->read_idx], &xfer->data, 1067 xfer->length); 1068 dev->read_idx += xfer->length; 1069 1070 if (dev->read_idx == dev->read_len) 1071 complete(&dev->wait); 1072 1073 } else { 1074 hid_err(hdev, "unhandled report %#02x\n", xfer->report); 1075 } 1076 return 0; 1077 } 1078 1079 static struct hid_driver ft260_driver = { 1080 .name = "ft260", 1081 .id_table = ft260_devices, 1082 .probe = ft260_probe, 1083 .remove = ft260_remove, 1084 .raw_event = ft260_raw_event, 1085 }; 1086 1087 module_hid_driver(ft260_driver); 1088 MODULE_DESCRIPTION("FTDI FT260 USB HID to I2C host bridge"); 1089 MODULE_AUTHOR("Michael Zaidman <michael.zaidman@gmail.com>"); 1090 MODULE_LICENSE("GPL v2"); 1091