1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Apple Z2 touchscreen driver 4 * 5 * Copyright (C) The Asahi Linux Contributors 6 */ 7 8 #include <linux/delay.h> 9 #include <linux/firmware.h> 10 #include <linux/input.h> 11 #include <linux/input/mt.h> 12 #include <linux/input/touchscreen.h> 13 #include <linux/interrupt.h> 14 #include <linux/module.h> 15 #include <linux/of.h> 16 #include <linux/spi/spi.h> 17 #include <linux/unaligned.h> 18 19 #define APPLE_Z2_NUM_FINGERS_OFFSET 16 20 #define APPLE_Z2_FINGERS_OFFSET 24 21 #define APPLE_Z2_TOUCH_STARTED 3 22 #define APPLE_Z2_TOUCH_MOVED 4 23 #define APPLE_Z2_CMD_READ_INTERRUPT_DATA 0xEB 24 #define APPLE_Z2_HBPP_CMD_BLOB 0x3001 25 #define APPLE_Z2_FW_MAGIC 0x5746325A 26 #define LOAD_COMMAND_INIT_PAYLOAD 0 27 #define LOAD_COMMAND_SEND_BLOB 1 28 #define LOAD_COMMAND_SEND_CALIBRATION 2 29 #define CAL_PROP_NAME "apple,z2-cal-blob" 30 31 struct apple_z2 { 32 struct spi_device *spidev; 33 struct gpio_desc *reset_gpio; 34 struct input_dev *input_dev; 35 struct completion boot_irq; 36 bool booted; 37 int index_parity; 38 struct touchscreen_properties props; 39 const char *fw_name; 40 u8 *tx_buf; 41 u8 *rx_buf; 42 }; 43 44 struct apple_z2_finger { 45 u8 finger; 46 u8 state; 47 __le16 unknown2; 48 __le16 abs_x; 49 __le16 abs_y; 50 __le16 rel_x; 51 __le16 rel_y; 52 __le16 tool_major; 53 __le16 tool_minor; 54 __le16 orientation; 55 __le16 touch_major; 56 __le16 touch_minor; 57 __le16 unused[2]; 58 __le16 pressure; 59 __le16 multi; 60 } __packed; 61 62 struct apple_z2_hbpp_blob_hdr { 63 __le16 cmd; 64 __le16 len; 65 __le32 addr; 66 __le16 checksum; 67 }; 68 69 struct apple_z2_fw_hdr { 70 __le32 magic; 71 __le32 version; 72 }; 73 74 struct apple_z2_read_interrupt_cmd { 75 u8 cmd; 76 u8 counter; 77 u8 unused[12]; 78 __le16 checksum; 79 }; 80 81 static void apple_z2_parse_touches(struct apple_z2 *z2, 82 const u8 *msg, size_t msg_len) 83 { 84 int i; 85 int nfingers; 86 int slot; 87 int slot_valid; 88 struct apple_z2_finger *fingers; 89 90 if (msg_len <= APPLE_Z2_NUM_FINGERS_OFFSET) 91 return; 92 nfingers = msg[APPLE_Z2_NUM_FINGERS_OFFSET]; 93 fingers = (struct apple_z2_finger *)(msg + APPLE_Z2_FINGERS_OFFSET); 94 for (i = 0; i < nfingers; i++) { 95 slot = input_mt_get_slot_by_key(z2->input_dev, fingers[i].finger); 96 if (slot < 0) { 97 dev_warn(&z2->spidev->dev, "unable to get slot for finger\n"); 98 continue; 99 } 100 slot_valid = fingers[i].state == APPLE_Z2_TOUCH_STARTED || 101 fingers[i].state == APPLE_Z2_TOUCH_MOVED; 102 input_mt_slot(z2->input_dev, slot); 103 if (!input_mt_report_slot_state(z2->input_dev, MT_TOOL_FINGER, slot_valid)) 104 continue; 105 touchscreen_report_pos(z2->input_dev, &z2->props, 106 le16_to_cpu(fingers[i].abs_x), 107 le16_to_cpu(fingers[i].abs_y), 108 true); 109 input_report_abs(z2->input_dev, ABS_MT_WIDTH_MAJOR, 110 le16_to_cpu(fingers[i].tool_major)); 111 input_report_abs(z2->input_dev, ABS_MT_WIDTH_MINOR, 112 le16_to_cpu(fingers[i].tool_minor)); 113 input_report_abs(z2->input_dev, ABS_MT_ORIENTATION, 114 le16_to_cpu(fingers[i].orientation)); 115 input_report_abs(z2->input_dev, ABS_MT_TOUCH_MAJOR, 116 le16_to_cpu(fingers[i].touch_major)); 117 input_report_abs(z2->input_dev, ABS_MT_TOUCH_MINOR, 118 le16_to_cpu(fingers[i].touch_minor)); 119 } 120 input_mt_sync_frame(z2->input_dev); 121 input_sync(z2->input_dev); 122 } 123 124 static int apple_z2_read_packet(struct apple_z2 *z2) 125 { 126 struct apple_z2_read_interrupt_cmd *len_cmd = (void *)z2->tx_buf; 127 struct spi_transfer xfer; 128 int error; 129 size_t pkt_len; 130 131 memset(&xfer, 0, sizeof(xfer)); 132 len_cmd->cmd = APPLE_Z2_CMD_READ_INTERRUPT_DATA; 133 len_cmd->counter = z2->index_parity + 1; 134 len_cmd->checksum = 135 cpu_to_le16(APPLE_Z2_CMD_READ_INTERRUPT_DATA + len_cmd->counter); 136 z2->index_parity = !z2->index_parity; 137 xfer.tx_buf = z2->tx_buf; 138 xfer.rx_buf = z2->rx_buf; 139 xfer.len = sizeof(*len_cmd); 140 141 error = spi_sync_transfer(z2->spidev, &xfer, 1); 142 if (error) 143 return error; 144 145 pkt_len = (get_unaligned_le16(z2->rx_buf + 1) + 8) & 0xfffffffc; 146 147 error = spi_read(z2->spidev, z2->rx_buf, pkt_len); 148 if (error) 149 return error; 150 151 apple_z2_parse_touches(z2, z2->rx_buf + 5, pkt_len - 5); 152 153 return 0; 154 } 155 156 static irqreturn_t apple_z2_irq(int irq, void *data) 157 { 158 struct apple_z2 *z2 = data; 159 160 if (unlikely(!z2->booted)) 161 complete(&z2->boot_irq); 162 else 163 apple_z2_read_packet(z2); 164 165 return IRQ_HANDLED; 166 } 167 168 /* Build calibration blob, caller is responsible for freeing the blob data. */ 169 static const u8 *apple_z2_build_cal_blob(struct apple_z2 *z2, 170 u32 address, size_t *size) 171 { 172 u8 *cal_data; 173 int cal_size; 174 size_t blob_size; 175 u32 checksum; 176 u16 checksum_hdr; 177 int i; 178 struct apple_z2_hbpp_blob_hdr *hdr; 179 int error; 180 181 if (!device_property_present(&z2->spidev->dev, CAL_PROP_NAME)) 182 return NULL; 183 184 cal_size = device_property_count_u8(&z2->spidev->dev, CAL_PROP_NAME); 185 if (cal_size < 0) 186 return ERR_PTR(cal_size); 187 188 blob_size = sizeof(struct apple_z2_hbpp_blob_hdr) + cal_size + sizeof(__le32); 189 u8 *blob_data __free(kfree) = kzalloc(blob_size, GFP_KERNEL); 190 if (!blob_data) 191 return ERR_PTR(-ENOMEM); 192 193 hdr = (struct apple_z2_hbpp_blob_hdr *)blob_data; 194 hdr->cmd = cpu_to_le16(APPLE_Z2_HBPP_CMD_BLOB); 195 hdr->len = cpu_to_le16(round_up(cal_size, 4) / 4); 196 hdr->addr = cpu_to_le32(address); 197 198 checksum_hdr = 0; 199 for (i = 2; i < 8; i++) 200 checksum_hdr += blob_data[i]; 201 hdr->checksum = cpu_to_le16(checksum_hdr); 202 203 cal_data = blob_data + sizeof(struct apple_z2_hbpp_blob_hdr); 204 error = device_property_read_u8_array(&z2->spidev->dev, CAL_PROP_NAME, 205 cal_data, cal_size); 206 if (error) 207 return ERR_PTR(error); 208 209 checksum = 0; 210 for (i = 0; i < cal_size; i++) 211 checksum += cal_data[i]; 212 put_unaligned_le32(checksum, cal_data + cal_size); 213 214 *size = blob_size; 215 return no_free_ptr(blob_data); 216 } 217 218 static int apple_z2_send_firmware_blob(struct apple_z2 *z2, const u8 *data, 219 u32 size, bool init) 220 { 221 struct spi_message msg; 222 struct spi_transfer blob_xfer, ack_xfer; 223 int error; 224 225 z2->tx_buf[0] = 0x1a; 226 z2->tx_buf[1] = 0xa1; 227 228 spi_message_init(&msg); 229 memset(&blob_xfer, 0, sizeof(blob_xfer)); 230 memset(&ack_xfer, 0, sizeof(ack_xfer)); 231 232 blob_xfer.tx_buf = data; 233 blob_xfer.len = size; 234 blob_xfer.bits_per_word = init ? 8 : 16; 235 spi_message_add_tail(&blob_xfer, &msg); 236 237 ack_xfer.tx_buf = z2->tx_buf; 238 ack_xfer.len = 2; 239 spi_message_add_tail(&ack_xfer, &msg); 240 241 reinit_completion(&z2->boot_irq); 242 error = spi_sync(z2->spidev, &msg); 243 if (error) 244 return error; 245 246 /* Irq only happens sometimes, but the thing boots reliably nonetheless */ 247 wait_for_completion_timeout(&z2->boot_irq, msecs_to_jiffies(20)); 248 249 return 0; 250 } 251 252 static int apple_z2_upload_firmware(struct apple_z2 *z2) 253 { 254 const struct apple_z2_fw_hdr *fw_hdr; 255 size_t fw_idx = sizeof(struct apple_z2_fw_hdr); 256 int error; 257 u32 load_cmd; 258 u32 address; 259 bool init; 260 size_t size; 261 262 const struct firmware *fw __free(firmware) = NULL; 263 error = request_firmware(&fw, z2->fw_name, &z2->spidev->dev); 264 if (error) { 265 dev_err(&z2->spidev->dev, "unable to load firmware\n"); 266 return error; 267 } 268 269 fw_hdr = (const struct apple_z2_fw_hdr *)fw->data; 270 if (le32_to_cpu(fw_hdr->magic) != APPLE_Z2_FW_MAGIC || le32_to_cpu(fw_hdr->version) != 1) { 271 dev_err(&z2->spidev->dev, "invalid firmware header\n"); 272 return -EINVAL; 273 } 274 275 /* 276 * This will interrupt the upload half-way if the file is malformed 277 * As the device has no non-volatile storage to corrupt, and gets reset 278 * on boot anyway, this is fine. 279 */ 280 while (fw_idx < fw->size) { 281 if (fw->size - fw_idx < 8) { 282 dev_err(&z2->spidev->dev, "firmware malformed\n"); 283 return -EINVAL; 284 } 285 286 load_cmd = le32_to_cpup((__force __le32 *)(fw->data + fw_idx)); 287 fw_idx += sizeof(u32); 288 if (load_cmd == LOAD_COMMAND_INIT_PAYLOAD || load_cmd == LOAD_COMMAND_SEND_BLOB) { 289 size = le32_to_cpup((__force __le32 *)(fw->data + fw_idx)); 290 fw_idx += sizeof(u32); 291 if (fw->size - fw_idx < size) { 292 dev_err(&z2->spidev->dev, "firmware malformed\n"); 293 return -EINVAL; 294 } 295 init = load_cmd == LOAD_COMMAND_INIT_PAYLOAD; 296 error = apple_z2_send_firmware_blob(z2, fw->data + fw_idx, 297 size, init); 298 if (error) 299 return error; 300 fw_idx += size; 301 } else if (load_cmd == LOAD_COMMAND_SEND_CALIBRATION) { 302 address = le32_to_cpup((__force __le32 *)(fw->data + fw_idx)); 303 fw_idx += sizeof(u32); 304 305 const u8 *data __free(kfree) = 306 apple_z2_build_cal_blob(z2, address, &size); 307 if (IS_ERR(data)) 308 return PTR_ERR(data); 309 310 if (data) { 311 error = apple_z2_send_firmware_blob(z2, data, size, false); 312 if (error) 313 return error; 314 } 315 } else { 316 dev_err(&z2->spidev->dev, "firmware malformed\n"); 317 return -EINVAL; 318 } 319 fw_idx = round_up(fw_idx, 4); 320 } 321 322 323 z2->booted = true; 324 apple_z2_read_packet(z2); 325 return 0; 326 } 327 328 static int apple_z2_boot(struct apple_z2 *z2) 329 { 330 int error; 331 332 reinit_completion(&z2->boot_irq); 333 enable_irq(z2->spidev->irq); 334 gpiod_set_value(z2->reset_gpio, 0); 335 if (!wait_for_completion_timeout(&z2->boot_irq, msecs_to_jiffies(20))) 336 return -ETIMEDOUT; 337 338 error = apple_z2_upload_firmware(z2); 339 if (error) { 340 gpiod_set_value(z2->reset_gpio, 1); 341 disable_irq(z2->spidev->irq); 342 return error; 343 } 344 345 return 0; 346 } 347 348 static int apple_z2_probe(struct spi_device *spi) 349 { 350 struct device *dev = &spi->dev; 351 struct apple_z2 *z2; 352 int error; 353 354 z2 = devm_kzalloc(dev, sizeof(*z2), GFP_KERNEL); 355 if (!z2) 356 return -ENOMEM; 357 358 z2->tx_buf = devm_kzalloc(dev, sizeof(struct apple_z2_read_interrupt_cmd), GFP_KERNEL); 359 if (!z2->tx_buf) 360 return -ENOMEM; 361 /* 4096 will end up being rounded up to 8192 due to devres header */ 362 z2->rx_buf = devm_kzalloc(dev, 4000, GFP_KERNEL); 363 if (!z2->rx_buf) 364 return -ENOMEM; 365 366 z2->spidev = spi; 367 init_completion(&z2->boot_irq); 368 spi_set_drvdata(spi, z2); 369 370 /* Reset the device on boot */ 371 z2->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); 372 if (IS_ERR(z2->reset_gpio)) 373 return dev_err_probe(dev, PTR_ERR(z2->reset_gpio), "unable to get reset\n"); 374 375 error = devm_request_threaded_irq(dev, z2->spidev->irq, NULL, apple_z2_irq, 376 IRQF_ONESHOT | IRQF_NO_AUTOEN, 377 "apple-z2-irq", z2); 378 if (error) 379 return dev_err_probe(dev, error, "unable to request irq\n"); 380 381 error = device_property_read_string(dev, "firmware-name", &z2->fw_name); 382 if (error) 383 return dev_err_probe(dev, error, "unable to get firmware name\n"); 384 385 z2->input_dev = devm_input_allocate_device(dev); 386 if (!z2->input_dev) 387 return -ENOMEM; 388 389 z2->input_dev->name = (char *)spi_get_device_id(spi)->driver_data; 390 z2->input_dev->phys = "apple_z2"; 391 z2->input_dev->id.bustype = BUS_SPI; 392 393 /* Allocate the axes before setting from DT */ 394 input_set_abs_params(z2->input_dev, ABS_MT_POSITION_X, 0, 0, 0, 0); 395 input_set_abs_params(z2->input_dev, ABS_MT_POSITION_Y, 0, 0, 0, 0); 396 touchscreen_parse_properties(z2->input_dev, true, &z2->props); 397 input_abs_set_res(z2->input_dev, ABS_MT_POSITION_X, 100); 398 input_abs_set_res(z2->input_dev, ABS_MT_POSITION_Y, 100); 399 input_set_abs_params(z2->input_dev, ABS_MT_WIDTH_MAJOR, 0, 65535, 0, 0); 400 input_set_abs_params(z2->input_dev, ABS_MT_WIDTH_MINOR, 0, 65535, 0, 0); 401 input_set_abs_params(z2->input_dev, ABS_MT_TOUCH_MAJOR, 0, 65535, 0, 0); 402 input_set_abs_params(z2->input_dev, ABS_MT_TOUCH_MINOR, 0, 65535, 0, 0); 403 input_set_abs_params(z2->input_dev, ABS_MT_ORIENTATION, -32768, 32767, 0, 0); 404 405 error = input_mt_init_slots(z2->input_dev, 256, INPUT_MT_DIRECT); 406 if (error) 407 return dev_err_probe(dev, error, "unable to initialize multitouch slots\n"); 408 409 error = input_register_device(z2->input_dev); 410 if (error) 411 return dev_err_probe(dev, error, "unable to register input device\n"); 412 413 /* Wait for device reset to finish */ 414 usleep_range(5000, 10000); 415 error = apple_z2_boot(z2); 416 if (error) 417 return error; 418 419 return 0; 420 } 421 422 static void apple_z2_shutdown(struct spi_device *spi) 423 { 424 struct apple_z2 *z2 = spi_get_drvdata(spi); 425 426 disable_irq(z2->spidev->irq); 427 gpiod_direction_output(z2->reset_gpio, 1); 428 z2->booted = false; 429 } 430 431 static int apple_z2_suspend(struct device *dev) 432 { 433 apple_z2_shutdown(to_spi_device(dev)); 434 435 return 0; 436 } 437 438 static int apple_z2_resume(struct device *dev) 439 { 440 struct apple_z2 *z2 = spi_get_drvdata(to_spi_device(dev)); 441 442 return apple_z2_boot(z2); 443 } 444 445 static DEFINE_SIMPLE_DEV_PM_OPS(apple_z2_pm, apple_z2_suspend, apple_z2_resume); 446 447 static const struct of_device_id apple_z2_of_match[] = { 448 { .compatible = "apple,j293-touchbar" }, 449 { .compatible = "apple,j493-touchbar" }, 450 {} 451 }; 452 MODULE_DEVICE_TABLE(of, apple_z2_of_match); 453 454 static struct spi_device_id apple_z2_of_id[] = { 455 { .name = "j293-touchbar", .driver_data = (kernel_ulong_t)"MacBookPro17,1 Touch Bar" }, 456 { .name = "j493-touchbar", .driver_data = (kernel_ulong_t)"Mac14,7 Touch Bar" }, 457 {} 458 }; 459 MODULE_DEVICE_TABLE(spi, apple_z2_of_id); 460 461 static struct spi_driver apple_z2_driver = { 462 .driver = { 463 .name = "apple-z2", 464 .pm = pm_sleep_ptr(&apple_z2_pm), 465 .of_match_table = apple_z2_of_match, 466 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 467 }, 468 .id_table = apple_z2_of_id, 469 .probe = apple_z2_probe, 470 .remove = apple_z2_shutdown, 471 }; 472 473 module_spi_driver(apple_z2_driver); 474 475 MODULE_LICENSE("GPL"); 476 MODULE_FIRMWARE("apple/dfrmtfw-*.bin"); 477 MODULE_DESCRIPTION("Apple Z2 touchscreens driver"); 478