1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Support for OLPC XO-1 System Control Interrupts (SCI) 4 * 5 * Copyright (C) 2010 One Laptop per Child 6 * Copyright (C) 2006 Red Hat, Inc. 7 * Copyright (C) 2006 Advanced Micro Devices, Inc. 8 */ 9 10 #include <linux/cs5535.h> 11 #include <linux/device.h> 12 #include <linux/gpio.h> 13 #include <linux/input.h> 14 #include <linux/interrupt.h> 15 #include <linux/platform_device.h> 16 #include <linux/pm.h> 17 #include <linux/pm_wakeup.h> 18 #include <linux/power_supply.h> 19 #include <linux/suspend.h> 20 #include <linux/workqueue.h> 21 #include <linux/olpc-ec.h> 22 23 #include <asm/io.h> 24 #include <asm/msr.h> 25 #include <asm/olpc.h> 26 27 #define DRV_NAME "olpc-xo1-sci" 28 #define PFX DRV_NAME ": " 29 30 static unsigned long acpi_base; 31 static struct input_dev *power_button_idev; 32 static struct input_dev *ebook_switch_idev; 33 static struct input_dev *lid_switch_idev; 34 35 static int sci_irq; 36 37 static bool lid_open; 38 static bool lid_inverted; 39 static int lid_wake_mode; 40 41 enum lid_wake_modes { 42 LID_WAKE_ALWAYS, 43 LID_WAKE_OPEN, 44 LID_WAKE_CLOSE, 45 }; 46 47 static const char * const lid_wake_mode_names[] = { 48 [LID_WAKE_ALWAYS] = "always", 49 [LID_WAKE_OPEN] = "open", 50 [LID_WAKE_CLOSE] = "close", 51 }; 52 53 static void battery_status_changed(void) 54 { 55 struct power_supply *psy = power_supply_get_by_name("olpc_battery"); 56 57 if (psy) { 58 power_supply_changed(psy); 59 power_supply_put(psy); 60 } 61 } 62 63 static void ac_status_changed(void) 64 { 65 struct power_supply *psy = power_supply_get_by_name("olpc_ac"); 66 67 if (psy) { 68 power_supply_changed(psy); 69 power_supply_put(psy); 70 } 71 } 72 73 /* Report current ebook switch state through input layer */ 74 static void send_ebook_state(void) 75 { 76 unsigned char state; 77 78 if (olpc_ec_cmd(EC_READ_EB_MODE, NULL, 0, &state, 1)) { 79 pr_err(PFX "failed to get ebook state\n"); 80 return; 81 } 82 83 if (test_bit(SW_TABLET_MODE, ebook_switch_idev->sw) == !!state) 84 return; /* Nothing new to report. */ 85 86 input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state); 87 input_sync(ebook_switch_idev); 88 pm_wakeup_event(&ebook_switch_idev->dev, 0); 89 } 90 91 static void flip_lid_inverter(void) 92 { 93 /* gpio is high; invert so we'll get l->h event interrupt */ 94 if (lid_inverted) 95 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 96 else 97 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 98 lid_inverted = !lid_inverted; 99 } 100 101 static void detect_lid_state(void) 102 { 103 /* 104 * the edge detector hookup on the gpio inputs on the geode is 105 * odd, to say the least. See http://dev.laptop.org/ticket/5703 106 * for details, but in a nutshell: we don't use the edge 107 * detectors. instead, we make use of an anomaly: with the both 108 * edge detectors turned off, we still get an edge event on a 109 * positive edge transition. to take advantage of this, we use the 110 * front-end inverter to ensure that that's the edge we're always 111 * going to see next. 112 */ 113 114 int state; 115 116 state = cs5535_gpio_isset(OLPC_GPIO_LID, GPIO_READ_BACK); 117 lid_open = !state ^ !lid_inverted; /* x ^^ y */ 118 if (!state) 119 return; 120 121 flip_lid_inverter(); 122 } 123 124 /* Report current lid switch state through input layer */ 125 static void send_lid_state(void) 126 { 127 if (!!test_bit(SW_LID, lid_switch_idev->sw) == !lid_open) 128 return; /* Nothing new to report. */ 129 130 input_report_switch(lid_switch_idev, SW_LID, !lid_open); 131 input_sync(lid_switch_idev); 132 pm_wakeup_event(&lid_switch_idev->dev, 0); 133 } 134 135 static ssize_t lid_wake_mode_show(struct device *dev, 136 struct device_attribute *attr, char *buf) 137 { 138 const char *mode = lid_wake_mode_names[lid_wake_mode]; 139 return sprintf(buf, "%s\n", mode); 140 } 141 static ssize_t lid_wake_mode_set(struct device *dev, 142 struct device_attribute *attr, 143 const char *buf, size_t count) 144 { 145 int i; 146 for (i = 0; i < ARRAY_SIZE(lid_wake_mode_names); i++) { 147 const char *mode = lid_wake_mode_names[i]; 148 if (strlen(mode) != count || strncasecmp(mode, buf, count)) 149 continue; 150 151 lid_wake_mode = i; 152 return count; 153 } 154 return -EINVAL; 155 } 156 static DEVICE_ATTR(lid_wake_mode, S_IWUSR | S_IRUGO, lid_wake_mode_show, 157 lid_wake_mode_set); 158 159 static struct attribute *lid_attrs[] = { 160 &dev_attr_lid_wake_mode.attr, 161 NULL, 162 }; 163 ATTRIBUTE_GROUPS(lid); 164 165 /* 166 * Process all items in the EC's SCI queue. 167 * 168 * This is handled in a workqueue because olpc_ec_cmd can be slow (and 169 * can even timeout). 170 * 171 * If propagate_events is false, the queue is drained without events being 172 * generated for the interrupts. 173 */ 174 static void process_sci_queue(bool propagate_events) 175 { 176 int r; 177 u16 data; 178 179 do { 180 r = olpc_ec_sci_query(&data); 181 if (r || !data) 182 break; 183 184 pr_debug(PFX "SCI 0x%x received\n", data); 185 186 switch (data) { 187 case EC_SCI_SRC_BATERR: 188 case EC_SCI_SRC_BATSOC: 189 case EC_SCI_SRC_BATTERY: 190 case EC_SCI_SRC_BATCRIT: 191 battery_status_changed(); 192 break; 193 case EC_SCI_SRC_ACPWR: 194 ac_status_changed(); 195 break; 196 } 197 198 if (data == EC_SCI_SRC_EBOOK && propagate_events) 199 send_ebook_state(); 200 } while (data); 201 202 if (r) 203 pr_err(PFX "Failed to clear SCI queue"); 204 } 205 206 static void process_sci_queue_work(struct work_struct *work) 207 { 208 process_sci_queue(true); 209 } 210 211 static DECLARE_WORK(sci_work, process_sci_queue_work); 212 213 static irqreturn_t xo1_sci_intr(int irq, void *dev_id) 214 { 215 struct platform_device *pdev = dev_id; 216 u32 sts; 217 u32 gpe; 218 219 sts = inl(acpi_base + CS5536_PM1_STS); 220 outl(sts | 0xffff, acpi_base + CS5536_PM1_STS); 221 222 gpe = inl(acpi_base + CS5536_PM_GPE0_STS); 223 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 224 225 dev_dbg(&pdev->dev, "sts %x gpe %x\n", sts, gpe); 226 227 if (sts & CS5536_PWRBTN_FLAG) { 228 if (!(sts & CS5536_WAK_FLAG)) { 229 /* Only report power button input when it was pressed 230 * during regular operation (as opposed to when it 231 * was used to wake the system). */ 232 input_report_key(power_button_idev, KEY_POWER, 1); 233 input_sync(power_button_idev); 234 input_report_key(power_button_idev, KEY_POWER, 0); 235 input_sync(power_button_idev); 236 } 237 /* Report the wakeup event in all cases. */ 238 pm_wakeup_event(&power_button_idev->dev, 0); 239 } 240 241 if ((sts & (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) == 242 (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) { 243 /* When the system is woken by the RTC alarm, report the 244 * event on the rtc device. */ 245 struct device *rtc = bus_find_device_by_name( 246 &platform_bus_type, NULL, "rtc_cmos"); 247 if (rtc) { 248 pm_wakeup_event(rtc, 0); 249 put_device(rtc); 250 } 251 } 252 253 if (gpe & CS5536_GPIOM7_PME_FLAG) { /* EC GPIO */ 254 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS); 255 schedule_work(&sci_work); 256 } 257 258 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 259 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 260 detect_lid_state(); 261 send_lid_state(); 262 263 return IRQ_HANDLED; 264 } 265 266 static int xo1_sci_suspend(struct platform_device *pdev, pm_message_t state) 267 { 268 if (device_may_wakeup(&power_button_idev->dev)) 269 olpc_xo1_pm_wakeup_set(CS5536_PM_PWRBTN); 270 else 271 olpc_xo1_pm_wakeup_clear(CS5536_PM_PWRBTN); 272 273 if (device_may_wakeup(&ebook_switch_idev->dev)) 274 olpc_ec_wakeup_set(EC_SCI_SRC_EBOOK); 275 else 276 olpc_ec_wakeup_clear(EC_SCI_SRC_EBOOK); 277 278 if (!device_may_wakeup(&lid_switch_idev->dev)) { 279 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 280 } else if ((lid_open && lid_wake_mode == LID_WAKE_OPEN) || 281 (!lid_open && lid_wake_mode == LID_WAKE_CLOSE)) { 282 flip_lid_inverter(); 283 284 /* we may have just caused an event */ 285 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 286 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 287 288 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 289 } 290 291 return 0; 292 } 293 294 static int xo1_sci_resume(struct platform_device *pdev) 295 { 296 /* 297 * We don't know what may have happened while we were asleep. 298 * Reestablish our lid setup so we're sure to catch all transitions. 299 */ 300 detect_lid_state(); 301 send_lid_state(); 302 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 303 304 /* Enable all EC events */ 305 olpc_ec_mask_write(EC_SCI_SRC_ALL); 306 307 /* Power/battery status might have changed too */ 308 battery_status_changed(); 309 ac_status_changed(); 310 return 0; 311 } 312 313 static int setup_sci_interrupt(struct platform_device *pdev) 314 { 315 u32 lo, hi; 316 u32 sts; 317 int r; 318 319 rdmsr(0x51400020, lo, hi); 320 sci_irq = (lo >> 20) & 15; 321 322 if (sci_irq) { 323 dev_info(&pdev->dev, "SCI is mapped to IRQ %d\n", sci_irq); 324 } else { 325 /* Zero means masked */ 326 dev_info(&pdev->dev, "SCI unmapped. Mapping to IRQ 3\n"); 327 sci_irq = 3; 328 lo |= 0x00300000; 329 wrmsrl(0x51400020, lo); 330 } 331 332 /* Select level triggered in PIC */ 333 if (sci_irq < 8) { 334 lo = inb(CS5536_PIC_INT_SEL1); 335 lo |= 1 << sci_irq; 336 outb(lo, CS5536_PIC_INT_SEL1); 337 } else { 338 lo = inb(CS5536_PIC_INT_SEL2); 339 lo |= 1 << (sci_irq - 8); 340 outb(lo, CS5536_PIC_INT_SEL2); 341 } 342 343 /* Enable interesting SCI events, and clear pending interrupts */ 344 sts = inl(acpi_base + CS5536_PM1_STS); 345 outl(((CS5536_PM_PWRBTN | CS5536_PM_RTC) << 16) | 0xffff, 346 acpi_base + CS5536_PM1_STS); 347 348 r = request_irq(sci_irq, xo1_sci_intr, 0, DRV_NAME, pdev); 349 if (r) 350 dev_err(&pdev->dev, "can't request interrupt\n"); 351 352 return r; 353 } 354 355 static int setup_ec_sci(void) 356 { 357 int r; 358 359 r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI"); 360 if (r) 361 return r; 362 363 gpio_direction_input(OLPC_GPIO_ECSCI); 364 365 /* Clear pending EC SCI events */ 366 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS); 367 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_POSITIVE_EDGE_STS); 368 369 /* 370 * Enable EC SCI events, and map them to both a PME and the SCI 371 * interrupt. 372 * 373 * Ordinarily, in addition to functioning as GPIOs, Geode GPIOs can 374 * be mapped to regular interrupts *or* Geode-specific Power 375 * Management Events (PMEs) - events that bring the system out of 376 * suspend. In this case, we want both of those things - the system 377 * wakeup, *and* the ability to get an interrupt when an event occurs. 378 * 379 * To achieve this, we map the GPIO to a PME, and then we use one 380 * of the many generic knobs on the CS5535 PIC to additionally map the 381 * PME to the regular SCI interrupt line. 382 */ 383 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_EVENTS_ENABLE); 384 385 /* Set the SCI to cause a PME event on group 7 */ 386 cs5535_gpio_setup_event(OLPC_GPIO_ECSCI, 7, 1); 387 388 /* And have group 7 also fire the SCI interrupt */ 389 cs5535_pic_unreqz_select_high(7, sci_irq); 390 391 return 0; 392 } 393 394 static void free_ec_sci(void) 395 { 396 gpio_free(OLPC_GPIO_ECSCI); 397 } 398 399 static int setup_lid_events(void) 400 { 401 int r; 402 403 r = gpio_request(OLPC_GPIO_LID, "OLPC-LID"); 404 if (r) 405 return r; 406 407 gpio_direction_input(OLPC_GPIO_LID); 408 409 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 410 lid_inverted = 0; 411 412 /* Clear edge detection and event enable for now */ 413 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 414 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_EN); 415 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_EN); 416 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 417 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 418 419 /* Set the LID to cause an PME event on group 6 */ 420 cs5535_gpio_setup_event(OLPC_GPIO_LID, 6, 1); 421 422 /* Set PME group 6 to fire the SCI interrupt */ 423 cs5535_gpio_set_irq(6, sci_irq); 424 425 /* Enable the event */ 426 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 427 428 return 0; 429 } 430 431 static void free_lid_events(void) 432 { 433 gpio_free(OLPC_GPIO_LID); 434 } 435 436 static int setup_power_button(struct platform_device *pdev) 437 { 438 int r; 439 440 power_button_idev = input_allocate_device(); 441 if (!power_button_idev) 442 return -ENOMEM; 443 444 power_button_idev->name = "Power Button"; 445 power_button_idev->phys = DRV_NAME "/input0"; 446 set_bit(EV_KEY, power_button_idev->evbit); 447 set_bit(KEY_POWER, power_button_idev->keybit); 448 449 power_button_idev->dev.parent = &pdev->dev; 450 device_init_wakeup(&power_button_idev->dev, 1); 451 452 r = input_register_device(power_button_idev); 453 if (r) { 454 dev_err(&pdev->dev, "failed to register power button: %d\n", r); 455 input_free_device(power_button_idev); 456 } 457 458 return r; 459 } 460 461 static void free_power_button(void) 462 { 463 input_unregister_device(power_button_idev); 464 } 465 466 static int setup_ebook_switch(struct platform_device *pdev) 467 { 468 int r; 469 470 ebook_switch_idev = input_allocate_device(); 471 if (!ebook_switch_idev) 472 return -ENOMEM; 473 474 ebook_switch_idev->name = "EBook Switch"; 475 ebook_switch_idev->phys = DRV_NAME "/input1"; 476 set_bit(EV_SW, ebook_switch_idev->evbit); 477 set_bit(SW_TABLET_MODE, ebook_switch_idev->swbit); 478 479 ebook_switch_idev->dev.parent = &pdev->dev; 480 device_set_wakeup_capable(&ebook_switch_idev->dev, true); 481 482 r = input_register_device(ebook_switch_idev); 483 if (r) { 484 dev_err(&pdev->dev, "failed to register ebook switch: %d\n", r); 485 input_free_device(ebook_switch_idev); 486 } 487 488 return r; 489 } 490 491 static void free_ebook_switch(void) 492 { 493 input_unregister_device(ebook_switch_idev); 494 } 495 496 static int setup_lid_switch(struct platform_device *pdev) 497 { 498 int r; 499 500 lid_switch_idev = input_allocate_device(); 501 if (!lid_switch_idev) 502 return -ENOMEM; 503 504 lid_switch_idev->name = "Lid Switch"; 505 lid_switch_idev->phys = DRV_NAME "/input2"; 506 set_bit(EV_SW, lid_switch_idev->evbit); 507 set_bit(SW_LID, lid_switch_idev->swbit); 508 509 lid_switch_idev->dev.parent = &pdev->dev; 510 device_set_wakeup_capable(&lid_switch_idev->dev, true); 511 512 r = input_register_device(lid_switch_idev); 513 if (r) { 514 dev_err(&pdev->dev, "failed to register lid switch: %d\n", r); 515 goto err_register; 516 } 517 518 return 0; 519 520 err_register: 521 input_free_device(lid_switch_idev); 522 return r; 523 } 524 525 static void free_lid_switch(void) 526 { 527 input_unregister_device(lid_switch_idev); 528 } 529 530 static int xo1_sci_probe(struct platform_device *pdev) 531 { 532 struct resource *res; 533 int r; 534 535 /* don't run on non-XOs */ 536 if (!machine_is_olpc()) 537 return -ENODEV; 538 539 res = platform_get_resource(pdev, IORESOURCE_IO, 0); 540 if (!res) { 541 dev_err(&pdev->dev, "can't fetch device resource info\n"); 542 return -EIO; 543 } 544 acpi_base = res->start; 545 546 r = setup_power_button(pdev); 547 if (r) 548 return r; 549 550 r = setup_ebook_switch(pdev); 551 if (r) 552 goto err_ebook; 553 554 r = setup_lid_switch(pdev); 555 if (r) 556 goto err_lid; 557 558 r = setup_lid_events(); 559 if (r) 560 goto err_lidevt; 561 562 r = setup_ec_sci(); 563 if (r) 564 goto err_ecsci; 565 566 /* Enable PME generation for EC-generated events */ 567 outl(CS5536_GPIOM6_PME_EN | CS5536_GPIOM7_PME_EN, 568 acpi_base + CS5536_PM_GPE0_EN); 569 570 /* Clear pending events */ 571 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 572 process_sci_queue(false); 573 574 /* Initial sync */ 575 send_ebook_state(); 576 detect_lid_state(); 577 send_lid_state(); 578 579 r = setup_sci_interrupt(pdev); 580 if (r) 581 goto err_sci; 582 583 /* Enable all EC events */ 584 olpc_ec_mask_write(EC_SCI_SRC_ALL); 585 586 return r; 587 588 err_sci: 589 free_ec_sci(); 590 err_ecsci: 591 free_lid_events(); 592 err_lidevt: 593 free_lid_switch(); 594 err_lid: 595 free_ebook_switch(); 596 err_ebook: 597 free_power_button(); 598 return r; 599 } 600 601 static void xo1_sci_remove(struct platform_device *pdev) 602 { 603 free_irq(sci_irq, pdev); 604 cancel_work_sync(&sci_work); 605 free_ec_sci(); 606 free_lid_events(); 607 free_lid_switch(); 608 free_ebook_switch(); 609 free_power_button(); 610 acpi_base = 0; 611 } 612 613 static struct platform_driver xo1_sci_driver = { 614 .driver = { 615 .name = "olpc-xo1-sci-acpi", 616 .dev_groups = lid_groups, 617 }, 618 .probe = xo1_sci_probe, 619 .remove_new = xo1_sci_remove, 620 .suspend = xo1_sci_suspend, 621 .resume = xo1_sci_resume, 622 }; 623 624 static int __init xo1_sci_init(void) 625 { 626 return platform_driver_register(&xo1_sci_driver); 627 } 628 arch_initcall(xo1_sci_init); 629