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, u8 bus_busy) 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 | bus_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 u8 bus_busy; 373 int ret, usec, try = 100; 374 struct hid_device *hdev = dev->hdev; 375 struct ft260_i2c_write_request_report *rep = 376 (struct ft260_i2c_write_request_report *)data; 377 378 ret = ft260_hid_output_report(hdev, data, len); 379 if (ret < 0) { 380 hid_err(hdev, "%s: failed to start transfer, ret %d\n", 381 __func__, ret); 382 ft260_i2c_reset(hdev); 383 return ret; 384 } 385 386 /* transfer time = 1 / clock(KHz) * 9 bits * bytes */ 387 usec = len * 9000 / dev->clock; 388 if (usec > 2000) { 389 usec -= 1500; 390 usleep_range(usec, usec + 100); 391 ft260_dbg("wait %d usec, len %d\n", usec, len); 392 } 393 394 /* 395 * Do not check the busy bit for combined transactions 396 * since the controller keeps the bus busy between writing 397 * and reading IOs to ensure an atomic operation. 398 */ 399 if (rep->flag == FT260_FLAG_START) 400 bus_busy = 0; 401 else 402 bus_busy = FT260_I2C_STATUS_BUS_BUSY; 403 404 do { 405 ret = ft260_xfer_status(dev, bus_busy); 406 if (ret != -EAGAIN) 407 break; 408 } while (--try); 409 410 if (ret == 0) 411 return 0; 412 413 ft260_i2c_reset(hdev); 414 return -EIO; 415 } 416 417 static int ft260_i2c_write(struct ft260_device *dev, u8 addr, u8 *data, 418 int len, u8 flag) 419 { 420 int ret, wr_len, idx = 0; 421 struct hid_device *hdev = dev->hdev; 422 struct ft260_i2c_write_request_report *rep = 423 (struct ft260_i2c_write_request_report *)dev->write_buf; 424 425 if (len < 1) 426 return -EINVAL; 427 428 rep->flag = FT260_FLAG_START; 429 430 do { 431 if (len <= FT260_WR_DATA_MAX) { 432 wr_len = len; 433 if (flag == FT260_FLAG_START_STOP) 434 rep->flag |= FT260_FLAG_STOP; 435 } else { 436 wr_len = FT260_WR_DATA_MAX; 437 } 438 439 rep->report = FT260_I2C_DATA_REPORT_ID(wr_len); 440 rep->address = addr; 441 rep->length = wr_len; 442 443 memcpy(rep->data, &data[idx], wr_len); 444 445 ft260_dbg("rep %#02x addr %#02x off %d len %d wlen %d flag %#x d[0] %#02x\n", 446 rep->report, addr, idx, len, wr_len, 447 rep->flag, data[0]); 448 449 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, 450 wr_len + 4); 451 if (ret < 0) { 452 hid_err(hdev, "%s: failed with %d\n", __func__, ret); 453 return ret; 454 } 455 456 len -= wr_len; 457 idx += wr_len; 458 rep->flag = 0; 459 460 } while (len > 0); 461 462 return 0; 463 } 464 465 static int ft260_smbus_write(struct ft260_device *dev, u8 addr, u8 cmd, 466 u8 *data, u8 data_len, u8 flag) 467 { 468 int ret = 0; 469 int len = 4; 470 471 struct ft260_i2c_write_request_report *rep = 472 (struct ft260_i2c_write_request_report *)dev->write_buf; 473 474 if (data_len >= sizeof(rep->data)) 475 return -EINVAL; 476 477 rep->address = addr; 478 rep->data[0] = cmd; 479 rep->length = data_len + 1; 480 rep->flag = flag; 481 len += rep->length; 482 483 rep->report = FT260_I2C_DATA_REPORT_ID(len); 484 485 if (data_len > 0) 486 memcpy(&rep->data[1], data, data_len); 487 488 ft260_dbg("rep %#02x addr %#02x cmd %#02x datlen %d replen %d\n", 489 rep->report, addr, cmd, rep->length, len); 490 491 ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, len); 492 493 return ret; 494 } 495 496 static int ft260_i2c_read(struct ft260_device *dev, u8 addr, u8 *data, 497 u16 len, u8 flag) 498 { 499 u16 rd_len; 500 u16 rd_data_max = 60; 501 int timeout, ret = 0; 502 struct ft260_i2c_read_request_report rep; 503 struct hid_device *hdev = dev->hdev; 504 u8 bus_busy = 0; 505 506 if ((flag & FT260_FLAG_START_REPEATED) == FT260_FLAG_START_REPEATED) 507 flag = FT260_FLAG_START_REPEATED; 508 else 509 flag = FT260_FLAG_START; 510 do { 511 if (len <= rd_data_max) { 512 rd_len = len; 513 flag |= FT260_FLAG_STOP; 514 } else { 515 rd_len = rd_data_max; 516 } 517 rd_data_max = FT260_RD_DATA_MAX; 518 519 rep.report = FT260_I2C_READ_REQ; 520 rep.length = cpu_to_le16(rd_len); 521 rep.address = addr; 522 rep.flag = flag; 523 524 ft260_dbg("rep %#02x addr %#02x len %d rlen %d flag %#x\n", 525 rep.report, rep.address, len, rd_len, flag); 526 527 reinit_completion(&dev->wait); 528 529 dev->read_idx = 0; 530 dev->read_buf = data; 531 dev->read_len = rd_len; 532 533 ret = ft260_hid_output_report(hdev, (u8 *)&rep, sizeof(rep)); 534 if (ret < 0) { 535 hid_err(hdev, "%s: failed with %d\n", __func__, ret); 536 goto ft260_i2c_read_exit; 537 } 538 539 timeout = msecs_to_jiffies(5000); 540 if (!wait_for_completion_timeout(&dev->wait, timeout)) { 541 ret = -ETIMEDOUT; 542 ft260_i2c_reset(hdev); 543 goto ft260_i2c_read_exit; 544 } 545 546 dev->read_buf = NULL; 547 548 if (flag & FT260_FLAG_STOP) 549 bus_busy = FT260_I2C_STATUS_BUS_BUSY; 550 551 ret = ft260_xfer_status(dev, bus_busy); 552 if (ret < 0) { 553 ret = -EIO; 554 ft260_i2c_reset(hdev); 555 goto ft260_i2c_read_exit; 556 } 557 558 len -= rd_len; 559 data += rd_len; 560 flag = 0; 561 562 } while (len > 0); 563 564 ft260_i2c_read_exit: 565 dev->read_buf = NULL; 566 return ret; 567 } 568 569 /* 570 * A random read operation is implemented as a dummy write operation, followed 571 * by a current address read operation. The dummy write operation is used to 572 * load the target byte address into the current byte address counter, from 573 * which the subsequent current address read operation then reads. 574 */ 575 static int ft260_i2c_write_read(struct ft260_device *dev, struct i2c_msg *msgs) 576 { 577 int ret; 578 int wr_len = msgs[0].len; 579 int rd_len = msgs[1].len; 580 struct hid_device *hdev = dev->hdev; 581 u8 addr = msgs[0].addr; 582 u16 read_off = 0; 583 584 if (wr_len > 2) { 585 hid_err(hdev, "%s: invalid wr_len: %d\n", __func__, wr_len); 586 return -EOPNOTSUPP; 587 } 588 589 if (ft260_debug) { 590 if (wr_len == 2) 591 read_off = be16_to_cpu(*(__be16 *)msgs[0].buf); 592 else 593 read_off = *msgs[0].buf; 594 595 pr_info("%s: off %#x rlen %d wlen %d\n", __func__, 596 read_off, rd_len, wr_len); 597 } 598 599 ret = ft260_i2c_write(dev, addr, msgs[0].buf, wr_len, 600 FT260_FLAG_START); 601 if (ret < 0) 602 return ret; 603 604 ret = ft260_i2c_read(dev, addr, msgs[1].buf, rd_len, 605 FT260_FLAG_START_STOP_REPEATED); 606 if (ret < 0) 607 return ret; 608 609 return 0; 610 } 611 612 static int ft260_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 613 int num) 614 { 615 int ret; 616 struct ft260_device *dev = i2c_get_adapdata(adapter); 617 struct hid_device *hdev = dev->hdev; 618 619 mutex_lock(&dev->lock); 620 621 ret = hid_hw_power(hdev, PM_HINT_FULLON); 622 if (ret < 0) { 623 hid_err(hdev, "failed to enter FULLON power mode: %d\n", ret); 624 mutex_unlock(&dev->lock); 625 return ret; 626 } 627 628 if (num == 1) { 629 if (msgs->flags & I2C_M_RD) 630 ret = ft260_i2c_read(dev, msgs->addr, msgs->buf, 631 msgs->len, FT260_FLAG_START_STOP); 632 else 633 ret = ft260_i2c_write(dev, msgs->addr, msgs->buf, 634 msgs->len, FT260_FLAG_START_STOP); 635 if (ret < 0) 636 goto i2c_exit; 637 638 } else { 639 /* Combined write then read message */ 640 ret = ft260_i2c_write_read(dev, msgs); 641 if (ret < 0) 642 goto i2c_exit; 643 } 644 645 ret = num; 646 i2c_exit: 647 hid_hw_power(hdev, PM_HINT_NORMAL); 648 mutex_unlock(&dev->lock); 649 return ret; 650 } 651 652 static int ft260_smbus_xfer(struct i2c_adapter *adapter, u16 addr, u16 flags, 653 char read_write, u8 cmd, int size, 654 union i2c_smbus_data *data) 655 { 656 int ret; 657 struct ft260_device *dev = i2c_get_adapdata(adapter); 658 struct hid_device *hdev = dev->hdev; 659 660 ft260_dbg("smbus size %d\n", size); 661 662 mutex_lock(&dev->lock); 663 664 ret = hid_hw_power(hdev, PM_HINT_FULLON); 665 if (ret < 0) { 666 hid_err(hdev, "power management error: %d\n", ret); 667 mutex_unlock(&dev->lock); 668 return ret; 669 } 670 671 switch (size) { 672 case I2C_SMBUS_BYTE: 673 if (read_write == I2C_SMBUS_READ) 674 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 675 FT260_FLAG_START_STOP); 676 else 677 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 678 FT260_FLAG_START_STOP); 679 break; 680 case I2C_SMBUS_BYTE_DATA: 681 if (read_write == I2C_SMBUS_READ) { 682 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 683 FT260_FLAG_START); 684 if (ret) 685 goto smbus_exit; 686 687 ret = ft260_i2c_read(dev, addr, &data->byte, 1, 688 FT260_FLAG_START_STOP_REPEATED); 689 } else { 690 ret = ft260_smbus_write(dev, addr, cmd, &data->byte, 1, 691 FT260_FLAG_START_STOP); 692 } 693 break; 694 case I2C_SMBUS_WORD_DATA: 695 if (read_write == I2C_SMBUS_READ) { 696 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 697 FT260_FLAG_START); 698 if (ret) 699 goto smbus_exit; 700 701 ret = ft260_i2c_read(dev, addr, (u8 *)&data->word, 2, 702 FT260_FLAG_START_STOP_REPEATED); 703 } else { 704 ret = ft260_smbus_write(dev, addr, cmd, 705 (u8 *)&data->word, 2, 706 FT260_FLAG_START_STOP); 707 } 708 break; 709 case I2C_SMBUS_BLOCK_DATA: 710 if (read_write == I2C_SMBUS_READ) { 711 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 712 FT260_FLAG_START); 713 if (ret) 714 goto smbus_exit; 715 716 ret = ft260_i2c_read(dev, addr, data->block, 717 data->block[0] + 1, 718 FT260_FLAG_START_STOP_REPEATED); 719 } else { 720 ret = ft260_smbus_write(dev, addr, cmd, data->block, 721 data->block[0] + 1, 722 FT260_FLAG_START_STOP); 723 } 724 break; 725 case I2C_SMBUS_I2C_BLOCK_DATA: 726 if (read_write == I2C_SMBUS_READ) { 727 ret = ft260_smbus_write(dev, addr, cmd, NULL, 0, 728 FT260_FLAG_START); 729 if (ret) 730 goto smbus_exit; 731 732 ret = ft260_i2c_read(dev, addr, data->block + 1, 733 data->block[0], 734 FT260_FLAG_START_STOP_REPEATED); 735 } else { 736 ret = ft260_smbus_write(dev, addr, cmd, data->block + 1, 737 data->block[0], 738 FT260_FLAG_START_STOP); 739 } 740 break; 741 default: 742 hid_err(hdev, "unsupported smbus transaction size %d\n", size); 743 ret = -EOPNOTSUPP; 744 } 745 746 smbus_exit: 747 hid_hw_power(hdev, PM_HINT_NORMAL); 748 mutex_unlock(&dev->lock); 749 return ret; 750 } 751 752 static u32 ft260_functionality(struct i2c_adapter *adap) 753 { 754 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | 755 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 756 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; 757 } 758 759 static const struct i2c_adapter_quirks ft260_i2c_quirks = { 760 .flags = I2C_AQ_COMB_WRITE_THEN_READ, 761 .max_comb_1st_msg_len = 2, 762 }; 763 764 static const struct i2c_algorithm ft260_i2c_algo = { 765 .master_xfer = ft260_i2c_xfer, 766 .smbus_xfer = ft260_smbus_xfer, 767 .functionality = ft260_functionality, 768 }; 769 770 static int ft260_get_system_config(struct hid_device *hdev, 771 struct ft260_get_system_status_report *cfg) 772 { 773 int ret; 774 int len = sizeof(struct ft260_get_system_status_report); 775 776 ret = ft260_hid_feature_report_get(hdev, FT260_SYSTEM_SETTINGS, 777 (u8 *)cfg, len); 778 if (ret < 0) { 779 hid_err(hdev, "failed to retrieve system status\n"); 780 return ret; 781 } 782 return 0; 783 } 784 785 static int ft260_is_interface_enabled(struct hid_device *hdev) 786 { 787 struct ft260_get_system_status_report cfg; 788 struct usb_interface *usbif = to_usb_interface(hdev->dev.parent); 789 int interface = usbif->cur_altsetting->desc.bInterfaceNumber; 790 int ret; 791 792 ret = ft260_get_system_config(hdev, &cfg); 793 if (ret < 0) 794 return ret; 795 796 ft260_dbg("interface: 0x%02x\n", interface); 797 ft260_dbg("chip mode: 0x%02x\n", cfg.chip_mode); 798 ft260_dbg("clock_ctl: 0x%02x\n", cfg.clock_ctl); 799 ft260_dbg("i2c_enable: 0x%02x\n", cfg.i2c_enable); 800 ft260_dbg("uart_mode: 0x%02x\n", cfg.uart_mode); 801 802 switch (cfg.chip_mode) { 803 case FT260_MODE_ALL: 804 case FT260_MODE_BOTH: 805 if (interface == 1) 806 hid_info(hdev, "uart interface is not supported\n"); 807 else 808 ret = 1; 809 break; 810 case FT260_MODE_UART: 811 hid_info(hdev, "uart interface is not supported\n"); 812 break; 813 case FT260_MODE_I2C: 814 ret = 1; 815 break; 816 } 817 return ret; 818 } 819 820 static int ft260_byte_show(struct hid_device *hdev, int id, u8 *cfg, int len, 821 u8 *field, u8 *buf) 822 { 823 int ret; 824 825 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 826 if (ret < 0) 827 return ret; 828 829 return scnprintf(buf, PAGE_SIZE, "%d\n", *field); 830 } 831 832 static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len, 833 __le16 *field, u8 *buf) 834 { 835 int ret; 836 837 ret = ft260_hid_feature_report_get(hdev, id, cfg, len); 838 if (ret < 0) 839 return ret; 840 841 return scnprintf(buf, PAGE_SIZE, "%d\n", le16_to_cpu(*field)); 842 } 843 844 #define FT260_ATTR_SHOW(name, reptype, id, type, func) \ 845 static ssize_t name##_show(struct device *kdev, \ 846 struct device_attribute *attr, char *buf) \ 847 { \ 848 struct reptype rep; \ 849 struct hid_device *hdev = to_hid_device(kdev); \ 850 type *field = &rep.name; \ 851 int len = sizeof(rep); \ 852 \ 853 return func(hdev, id, (u8 *)&rep, len, field, buf); \ 854 } 855 856 #define FT260_SSTAT_ATTR_SHOW(name) \ 857 FT260_ATTR_SHOW(name, ft260_get_system_status_report, \ 858 FT260_SYSTEM_SETTINGS, u8, ft260_byte_show) 859 860 #define FT260_I2CST_ATTR_SHOW(name) \ 861 FT260_ATTR_SHOW(name, ft260_get_i2c_status_report, \ 862 FT260_I2C_STATUS, __le16, ft260_word_show) 863 864 #define FT260_ATTR_STORE(name, reptype, id, req, type, ctype, func) \ 865 static ssize_t name##_store(struct device *kdev, \ 866 struct device_attribute *attr, \ 867 const char *buf, size_t count) \ 868 { \ 869 struct reptype rep; \ 870 struct hid_device *hdev = to_hid_device(kdev); \ 871 type name; \ 872 int ret; \ 873 \ 874 if (!func(buf, 10, (ctype *)&name)) { \ 875 rep.name = name; \ 876 rep.report = id; \ 877 rep.request = req; \ 878 ret = ft260_hid_feature_report_set(hdev, (u8 *)&rep, \ 879 sizeof(rep)); \ 880 if (!ret) \ 881 ret = count; \ 882 } else { \ 883 ret = -EINVAL; \ 884 } \ 885 return ret; \ 886 } 887 888 #define FT260_BYTE_ATTR_STORE(name, reptype, req) \ 889 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 890 u8, u8, kstrtou8) 891 892 #define FT260_WORD_ATTR_STORE(name, reptype, req) \ 893 FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \ 894 __le16, u16, kstrtou16) 895 896 FT260_SSTAT_ATTR_SHOW(chip_mode); 897 static DEVICE_ATTR_RO(chip_mode); 898 899 FT260_SSTAT_ATTR_SHOW(pwren_status); 900 static DEVICE_ATTR_RO(pwren_status); 901 902 FT260_SSTAT_ATTR_SHOW(suspend_status); 903 static DEVICE_ATTR_RO(suspend_status); 904 905 FT260_SSTAT_ATTR_SHOW(hid_over_i2c_en); 906 static DEVICE_ATTR_RO(hid_over_i2c_en); 907 908 FT260_SSTAT_ATTR_SHOW(power_saving_en); 909 static DEVICE_ATTR_RO(power_saving_en); 910 911 FT260_SSTAT_ATTR_SHOW(i2c_enable); 912 FT260_BYTE_ATTR_STORE(i2c_enable, ft260_set_i2c_mode_report, 913 FT260_SET_I2C_MODE); 914 static DEVICE_ATTR_RW(i2c_enable); 915 916 FT260_SSTAT_ATTR_SHOW(uart_mode); 917 FT260_BYTE_ATTR_STORE(uart_mode, ft260_set_uart_mode_report, 918 FT260_SET_UART_MODE); 919 static DEVICE_ATTR_RW(uart_mode); 920 921 FT260_SSTAT_ATTR_SHOW(clock_ctl); 922 FT260_BYTE_ATTR_STORE(clock_ctl, ft260_set_system_clock_report, 923 FT260_SET_CLOCK); 924 static DEVICE_ATTR_RW(clock_ctl); 925 926 FT260_I2CST_ATTR_SHOW(clock); 927 FT260_WORD_ATTR_STORE(clock, ft260_set_i2c_speed_report, 928 FT260_SET_I2C_CLOCK_SPEED); 929 static DEVICE_ATTR_RW(clock); 930 931 static ssize_t i2c_reset_store(struct device *kdev, 932 struct device_attribute *attr, const char *buf, 933 size_t count) 934 { 935 struct hid_device *hdev = to_hid_device(kdev); 936 int ret = ft260_i2c_reset(hdev); 937 938 if (ret) 939 return ret; 940 return count; 941 } 942 static DEVICE_ATTR_WO(i2c_reset); 943 944 static const struct attribute_group ft260_attr_group = { 945 .attrs = (struct attribute *[]) { 946 &dev_attr_chip_mode.attr, 947 &dev_attr_pwren_status.attr, 948 &dev_attr_suspend_status.attr, 949 &dev_attr_hid_over_i2c_en.attr, 950 &dev_attr_power_saving_en.attr, 951 &dev_attr_i2c_enable.attr, 952 &dev_attr_uart_mode.attr, 953 &dev_attr_clock_ctl.attr, 954 &dev_attr_i2c_reset.attr, 955 &dev_attr_clock.attr, 956 NULL 957 } 958 }; 959 960 static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) 961 { 962 struct ft260_device *dev; 963 struct ft260_get_chip_version_report version; 964 int ret; 965 966 if (!hid_is_usb(hdev)) 967 return -EINVAL; 968 969 dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL); 970 if (!dev) 971 return -ENOMEM; 972 973 ret = hid_parse(hdev); 974 if (ret) { 975 hid_err(hdev, "failed to parse HID\n"); 976 return ret; 977 } 978 979 ret = hid_hw_start(hdev, 0); 980 if (ret) { 981 hid_err(hdev, "failed to start HID HW\n"); 982 return ret; 983 } 984 985 ret = hid_hw_open(hdev); 986 if (ret) { 987 hid_err(hdev, "failed to open HID HW\n"); 988 goto err_hid_stop; 989 } 990 991 ret = ft260_hid_feature_report_get(hdev, FT260_CHIP_VERSION, 992 (u8 *)&version, sizeof(version)); 993 if (ret < 0) { 994 hid_err(hdev, "failed to retrieve chip version\n"); 995 goto err_hid_close; 996 } 997 998 hid_info(hdev, "chip code: %02x%02x %02x%02x\n", 999 version.chip_code[0], version.chip_code[1], 1000 version.chip_code[2], version.chip_code[3]); 1001 1002 ret = ft260_is_interface_enabled(hdev); 1003 if (ret <= 0) 1004 goto err_hid_close; 1005 1006 hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", 1007 hdev->version >> 8, hdev->version & 0xff, hdev->name, 1008 hdev->phys); 1009 1010 hid_set_drvdata(hdev, dev); 1011 dev->hdev = hdev; 1012 dev->adap.owner = THIS_MODULE; 1013 dev->adap.class = I2C_CLASS_HWMON; 1014 dev->adap.algo = &ft260_i2c_algo; 1015 dev->adap.quirks = &ft260_i2c_quirks; 1016 dev->adap.dev.parent = &hdev->dev; 1017 snprintf(dev->adap.name, sizeof(dev->adap.name), 1018 "FT260 usb-i2c bridge"); 1019 1020 mutex_init(&dev->lock); 1021 init_completion(&dev->wait); 1022 1023 ret = ft260_xfer_status(dev, FT260_I2C_STATUS_BUS_BUSY); 1024 if (ret) 1025 ft260_i2c_reset(hdev); 1026 1027 i2c_set_adapdata(&dev->adap, dev); 1028 ret = i2c_add_adapter(&dev->adap); 1029 if (ret) { 1030 hid_err(hdev, "failed to add i2c adapter\n"); 1031 goto err_hid_close; 1032 } 1033 1034 ret = sysfs_create_group(&hdev->dev.kobj, &ft260_attr_group); 1035 if (ret < 0) { 1036 hid_err(hdev, "failed to create sysfs attrs\n"); 1037 goto err_i2c_free; 1038 } 1039 1040 return 0; 1041 1042 err_i2c_free: 1043 i2c_del_adapter(&dev->adap); 1044 err_hid_close: 1045 hid_hw_close(hdev); 1046 err_hid_stop: 1047 hid_hw_stop(hdev); 1048 return ret; 1049 } 1050 1051 static void ft260_remove(struct hid_device *hdev) 1052 { 1053 struct ft260_device *dev = hid_get_drvdata(hdev); 1054 1055 if (!dev) 1056 return; 1057 1058 sysfs_remove_group(&hdev->dev.kobj, &ft260_attr_group); 1059 i2c_del_adapter(&dev->adap); 1060 1061 hid_hw_close(hdev); 1062 hid_hw_stop(hdev); 1063 } 1064 1065 static int ft260_raw_event(struct hid_device *hdev, struct hid_report *report, 1066 u8 *data, int size) 1067 { 1068 struct ft260_device *dev = hid_get_drvdata(hdev); 1069 struct ft260_i2c_input_report *xfer = (void *)data; 1070 1071 if (xfer->report >= FT260_I2C_REPORT_MIN && 1072 xfer->report <= FT260_I2C_REPORT_MAX) { 1073 ft260_dbg("i2c resp: rep %#02x len %d\n", xfer->report, 1074 xfer->length); 1075 1076 if ((dev->read_buf == NULL) || 1077 (xfer->length > dev->read_len - dev->read_idx)) { 1078 hid_err(hdev, "unexpected report %#02x, length %d\n", 1079 xfer->report, xfer->length); 1080 return -1; 1081 } 1082 1083 memcpy(&dev->read_buf[dev->read_idx], &xfer->data, 1084 xfer->length); 1085 dev->read_idx += xfer->length; 1086 1087 if (dev->read_idx == dev->read_len) 1088 complete(&dev->wait); 1089 1090 } else { 1091 hid_err(hdev, "unhandled report %#02x\n", xfer->report); 1092 } 1093 return 0; 1094 } 1095 1096 static struct hid_driver ft260_driver = { 1097 .name = "ft260", 1098 .id_table = ft260_devices, 1099 .probe = ft260_probe, 1100 .remove = ft260_remove, 1101 .raw_event = ft260_raw_event, 1102 }; 1103 1104 module_hid_driver(ft260_driver); 1105 MODULE_DESCRIPTION("FTDI FT260 USB HID to I2C host bridge"); 1106 MODULE_AUTHOR("Michael Zaidman <michael.zaidman@gmail.com>"); 1107 MODULE_LICENSE("GPL v2"); 1108