1 /* 2 * Support for OLPC XO-1 System Control Interrupts (SCI) 3 * 4 * Copyright (C) 2010 One Laptop per Child 5 * Copyright (C) 2006 Red Hat, Inc. 6 * Copyright (C) 2006 Advanced Micro Devices, Inc. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 */ 13 14 #include <linux/cs5535.h> 15 #include <linux/device.h> 16 #include <linux/gpio.h> 17 #include <linux/input.h> 18 #include <linux/interrupt.h> 19 #include <linux/platform_device.h> 20 #include <linux/pm.h> 21 #include <linux/pm_wakeup.h> 22 #include <linux/mfd/core.h> 23 #include <linux/power_supply.h> 24 #include <linux/suspend.h> 25 #include <linux/workqueue.h> 26 #include <linux/olpc-ec.h> 27 28 #include <asm/io.h> 29 #include <asm/msr.h> 30 #include <asm/olpc.h> 31 32 #define DRV_NAME "olpc-xo1-sci" 33 #define PFX DRV_NAME ": " 34 35 static unsigned long acpi_base; 36 static struct input_dev *power_button_idev; 37 static struct input_dev *ebook_switch_idev; 38 static struct input_dev *lid_switch_idev; 39 40 static int sci_irq; 41 42 static bool lid_open; 43 static bool lid_inverted; 44 static int lid_wake_mode; 45 46 enum lid_wake_modes { 47 LID_WAKE_ALWAYS, 48 LID_WAKE_OPEN, 49 LID_WAKE_CLOSE, 50 }; 51 52 static const char * const lid_wake_mode_names[] = { 53 [LID_WAKE_ALWAYS] = "always", 54 [LID_WAKE_OPEN] = "open", 55 [LID_WAKE_CLOSE] = "close", 56 }; 57 58 static void battery_status_changed(void) 59 { 60 struct power_supply *psy = power_supply_get_by_name("olpc-battery"); 61 62 if (psy) { 63 power_supply_changed(psy); 64 power_supply_put(psy); 65 } 66 } 67 68 static void ac_status_changed(void) 69 { 70 struct power_supply *psy = power_supply_get_by_name("olpc-ac"); 71 72 if (psy) { 73 power_supply_changed(psy); 74 power_supply_put(psy); 75 } 76 } 77 78 /* Report current ebook switch state through input layer */ 79 static void send_ebook_state(void) 80 { 81 unsigned char state; 82 83 if (olpc_ec_cmd(EC_READ_EB_MODE, NULL, 0, &state, 1)) { 84 pr_err(PFX "failed to get ebook state\n"); 85 return; 86 } 87 88 if (!!test_bit(SW_TABLET_MODE, ebook_switch_idev->sw) == state) 89 return; /* Nothing new to report. */ 90 91 input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state); 92 input_sync(ebook_switch_idev); 93 pm_wakeup_event(&ebook_switch_idev->dev, 0); 94 } 95 96 static void flip_lid_inverter(void) 97 { 98 /* gpio is high; invert so we'll get l->h event interrupt */ 99 if (lid_inverted) 100 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 101 else 102 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 103 lid_inverted = !lid_inverted; 104 } 105 106 static void detect_lid_state(void) 107 { 108 /* 109 * the edge detector hookup on the gpio inputs on the geode is 110 * odd, to say the least. See http://dev.laptop.org/ticket/5703 111 * for details, but in a nutshell: we don't use the edge 112 * detectors. instead, we make use of an anomaly: with the both 113 * edge detectors turned off, we still get an edge event on a 114 * positive edge transition. to take advantage of this, we use the 115 * front-end inverter to ensure that that's the edge we're always 116 * going to see next. 117 */ 118 119 int state; 120 121 state = cs5535_gpio_isset(OLPC_GPIO_LID, GPIO_READ_BACK); 122 lid_open = !state ^ !lid_inverted; /* x ^^ y */ 123 if (!state) 124 return; 125 126 flip_lid_inverter(); 127 } 128 129 /* Report current lid switch state through input layer */ 130 static void send_lid_state(void) 131 { 132 if (!!test_bit(SW_LID, lid_switch_idev->sw) == !lid_open) 133 return; /* Nothing new to report. */ 134 135 input_report_switch(lid_switch_idev, SW_LID, !lid_open); 136 input_sync(lid_switch_idev); 137 pm_wakeup_event(&lid_switch_idev->dev, 0); 138 } 139 140 static ssize_t lid_wake_mode_show(struct device *dev, 141 struct device_attribute *attr, char *buf) 142 { 143 const char *mode = lid_wake_mode_names[lid_wake_mode]; 144 return sprintf(buf, "%s\n", mode); 145 } 146 static ssize_t lid_wake_mode_set(struct device *dev, 147 struct device_attribute *attr, 148 const char *buf, size_t count) 149 { 150 int i; 151 for (i = 0; i < ARRAY_SIZE(lid_wake_mode_names); i++) { 152 const char *mode = lid_wake_mode_names[i]; 153 if (strlen(mode) != count || strncasecmp(mode, buf, count)) 154 continue; 155 156 lid_wake_mode = i; 157 return count; 158 } 159 return -EINVAL; 160 } 161 static DEVICE_ATTR(lid_wake_mode, S_IWUSR | S_IRUGO, lid_wake_mode_show, 162 lid_wake_mode_set); 163 164 /* 165 * Process all items in the EC's SCI queue. 166 * 167 * This is handled in a workqueue because olpc_ec_cmd can be slow (and 168 * can even timeout). 169 * 170 * If propagate_events is false, the queue is drained without events being 171 * generated for the interrupts. 172 */ 173 static void process_sci_queue(bool propagate_events) 174 { 175 int r; 176 u16 data; 177 178 do { 179 r = olpc_ec_sci_query(&data); 180 if (r || !data) 181 break; 182 183 pr_debug(PFX "SCI 0x%x received\n", data); 184 185 switch (data) { 186 case EC_SCI_SRC_BATERR: 187 case EC_SCI_SRC_BATSOC: 188 case EC_SCI_SRC_BATTERY: 189 case EC_SCI_SRC_BATCRIT: 190 battery_status_changed(); 191 break; 192 case EC_SCI_SRC_ACPWR: 193 ac_status_changed(); 194 break; 195 } 196 197 if (data == EC_SCI_SRC_EBOOK && propagate_events) 198 send_ebook_state(); 199 } while (data); 200 201 if (r) 202 pr_err(PFX "Failed to clear SCI queue"); 203 } 204 205 static void process_sci_queue_work(struct work_struct *work) 206 { 207 process_sci_queue(true); 208 } 209 210 static DECLARE_WORK(sci_work, process_sci_queue_work); 211 212 static irqreturn_t xo1_sci_intr(int irq, void *dev_id) 213 { 214 struct platform_device *pdev = dev_id; 215 u32 sts; 216 u32 gpe; 217 218 sts = inl(acpi_base + CS5536_PM1_STS); 219 outl(sts | 0xffff, acpi_base + CS5536_PM1_STS); 220 221 gpe = inl(acpi_base + CS5536_PM_GPE0_STS); 222 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 223 224 dev_dbg(&pdev->dev, "sts %x gpe %x\n", sts, gpe); 225 226 if (sts & CS5536_PWRBTN_FLAG) { 227 if (!(sts & CS5536_WAK_FLAG)) { 228 /* Only report power button input when it was pressed 229 * during regular operation (as opposed to when it 230 * was used to wake the system). */ 231 input_report_key(power_button_idev, KEY_POWER, 1); 232 input_sync(power_button_idev); 233 input_report_key(power_button_idev, KEY_POWER, 0); 234 input_sync(power_button_idev); 235 } 236 /* Report the wakeup event in all cases. */ 237 pm_wakeup_event(&power_button_idev->dev, 0); 238 } 239 240 if ((sts & (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) == 241 (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) { 242 /* When the system is woken by the RTC alarm, report the 243 * event on the rtc device. */ 244 struct device *rtc = bus_find_device_by_name( 245 &platform_bus_type, NULL, "rtc_cmos"); 246 if (rtc) { 247 pm_wakeup_event(rtc, 0); 248 put_device(rtc); 249 } 250 } 251 252 if (gpe & CS5536_GPIOM7_PME_FLAG) { /* EC GPIO */ 253 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS); 254 schedule_work(&sci_work); 255 } 256 257 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 258 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 259 detect_lid_state(); 260 send_lid_state(); 261 262 return IRQ_HANDLED; 263 } 264 265 static int xo1_sci_suspend(struct platform_device *pdev, pm_message_t state) 266 { 267 if (device_may_wakeup(&power_button_idev->dev)) 268 olpc_xo1_pm_wakeup_set(CS5536_PM_PWRBTN); 269 else 270 olpc_xo1_pm_wakeup_clear(CS5536_PM_PWRBTN); 271 272 if (device_may_wakeup(&ebook_switch_idev->dev)) 273 olpc_ec_wakeup_set(EC_SCI_SRC_EBOOK); 274 else 275 olpc_ec_wakeup_clear(EC_SCI_SRC_EBOOK); 276 277 if (!device_may_wakeup(&lid_switch_idev->dev)) { 278 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 279 } else if ((lid_open && lid_wake_mode == LID_WAKE_OPEN) || 280 (!lid_open && lid_wake_mode == LID_WAKE_CLOSE)) { 281 flip_lid_inverter(); 282 283 /* we may have just caused an event */ 284 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 285 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 286 287 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 288 } 289 290 return 0; 291 } 292 293 static int xo1_sci_resume(struct platform_device *pdev) 294 { 295 /* 296 * We don't know what may have happened while we were asleep. 297 * Reestablish our lid setup so we're sure to catch all transitions. 298 */ 299 detect_lid_state(); 300 send_lid_state(); 301 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 302 303 /* Enable all EC events */ 304 olpc_ec_mask_write(EC_SCI_SRC_ALL); 305 306 /* Power/battery status might have changed too */ 307 battery_status_changed(); 308 ac_status_changed(); 309 return 0; 310 } 311 312 static int setup_sci_interrupt(struct platform_device *pdev) 313 { 314 u32 lo, hi; 315 u32 sts; 316 int r; 317 318 rdmsr(0x51400020, lo, hi); 319 sci_irq = (lo >> 20) & 15; 320 321 if (sci_irq) { 322 dev_info(&pdev->dev, "SCI is mapped to IRQ %d\n", sci_irq); 323 } else { 324 /* Zero means masked */ 325 dev_info(&pdev->dev, "SCI unmapped. Mapping to IRQ 3\n"); 326 sci_irq = 3; 327 lo |= 0x00300000; 328 wrmsrl(0x51400020, lo); 329 } 330 331 /* Select level triggered in PIC */ 332 if (sci_irq < 8) { 333 lo = inb(CS5536_PIC_INT_SEL1); 334 lo |= 1 << sci_irq; 335 outb(lo, CS5536_PIC_INT_SEL1); 336 } else { 337 lo = inb(CS5536_PIC_INT_SEL2); 338 lo |= 1 << (sci_irq - 8); 339 outb(lo, CS5536_PIC_INT_SEL2); 340 } 341 342 /* Enable interesting SCI events, and clear pending interrupts */ 343 sts = inl(acpi_base + CS5536_PM1_STS); 344 outl(((CS5536_PM_PWRBTN | CS5536_PM_RTC) << 16) | 0xffff, 345 acpi_base + CS5536_PM1_STS); 346 347 r = request_irq(sci_irq, xo1_sci_intr, 0, DRV_NAME, pdev); 348 if (r) 349 dev_err(&pdev->dev, "can't request interrupt\n"); 350 351 return r; 352 } 353 354 static int setup_ec_sci(void) 355 { 356 int r; 357 358 r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI"); 359 if (r) 360 return r; 361 362 gpio_direction_input(OLPC_GPIO_ECSCI); 363 364 /* Clear pending EC SCI events */ 365 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS); 366 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_POSITIVE_EDGE_STS); 367 368 /* 369 * Enable EC SCI events, and map them to both a PME and the SCI 370 * interrupt. 371 * 372 * Ordinarily, in addition to functioning as GPIOs, Geode GPIOs can 373 * be mapped to regular interrupts *or* Geode-specific Power 374 * Management Events (PMEs) - events that bring the system out of 375 * suspend. In this case, we want both of those things - the system 376 * wakeup, *and* the ability to get an interrupt when an event occurs. 377 * 378 * To achieve this, we map the GPIO to a PME, and then we use one 379 * of the many generic knobs on the CS5535 PIC to additionally map the 380 * PME to the regular SCI interrupt line. 381 */ 382 cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_EVENTS_ENABLE); 383 384 /* Set the SCI to cause a PME event on group 7 */ 385 cs5535_gpio_setup_event(OLPC_GPIO_ECSCI, 7, 1); 386 387 /* And have group 7 also fire the SCI interrupt */ 388 cs5535_pic_unreqz_select_high(7, sci_irq); 389 390 return 0; 391 } 392 393 static void free_ec_sci(void) 394 { 395 gpio_free(OLPC_GPIO_ECSCI); 396 } 397 398 static int setup_lid_events(void) 399 { 400 int r; 401 402 r = gpio_request(OLPC_GPIO_LID, "OLPC-LID"); 403 if (r) 404 return r; 405 406 gpio_direction_input(OLPC_GPIO_LID); 407 408 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT); 409 lid_inverted = 0; 410 411 /* Clear edge detection and event enable for now */ 412 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 413 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_EN); 414 cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_EN); 415 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS); 416 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS); 417 418 /* Set the LID to cause an PME event on group 6 */ 419 cs5535_gpio_setup_event(OLPC_GPIO_LID, 6, 1); 420 421 /* Set PME group 6 to fire the SCI interrupt */ 422 cs5535_gpio_set_irq(6, sci_irq); 423 424 /* Enable the event */ 425 cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE); 426 427 return 0; 428 } 429 430 static void free_lid_events(void) 431 { 432 gpio_free(OLPC_GPIO_LID); 433 } 434 435 static int setup_power_button(struct platform_device *pdev) 436 { 437 int r; 438 439 power_button_idev = input_allocate_device(); 440 if (!power_button_idev) 441 return -ENOMEM; 442 443 power_button_idev->name = "Power Button"; 444 power_button_idev->phys = DRV_NAME "/input0"; 445 set_bit(EV_KEY, power_button_idev->evbit); 446 set_bit(KEY_POWER, power_button_idev->keybit); 447 448 power_button_idev->dev.parent = &pdev->dev; 449 device_init_wakeup(&power_button_idev->dev, 1); 450 451 r = input_register_device(power_button_idev); 452 if (r) { 453 dev_err(&pdev->dev, "failed to register power button: %d\n", r); 454 input_free_device(power_button_idev); 455 } 456 457 return r; 458 } 459 460 static void free_power_button(void) 461 { 462 input_unregister_device(power_button_idev); 463 } 464 465 static int setup_ebook_switch(struct platform_device *pdev) 466 { 467 int r; 468 469 ebook_switch_idev = input_allocate_device(); 470 if (!ebook_switch_idev) 471 return -ENOMEM; 472 473 ebook_switch_idev->name = "EBook Switch"; 474 ebook_switch_idev->phys = DRV_NAME "/input1"; 475 set_bit(EV_SW, ebook_switch_idev->evbit); 476 set_bit(SW_TABLET_MODE, ebook_switch_idev->swbit); 477 478 ebook_switch_idev->dev.parent = &pdev->dev; 479 device_set_wakeup_capable(&ebook_switch_idev->dev, true); 480 481 r = input_register_device(ebook_switch_idev); 482 if (r) { 483 dev_err(&pdev->dev, "failed to register ebook switch: %d\n", r); 484 input_free_device(ebook_switch_idev); 485 } 486 487 return r; 488 } 489 490 static void free_ebook_switch(void) 491 { 492 input_unregister_device(ebook_switch_idev); 493 } 494 495 static int setup_lid_switch(struct platform_device *pdev) 496 { 497 int r; 498 499 lid_switch_idev = input_allocate_device(); 500 if (!lid_switch_idev) 501 return -ENOMEM; 502 503 lid_switch_idev->name = "Lid Switch"; 504 lid_switch_idev->phys = DRV_NAME "/input2"; 505 set_bit(EV_SW, lid_switch_idev->evbit); 506 set_bit(SW_LID, lid_switch_idev->swbit); 507 508 lid_switch_idev->dev.parent = &pdev->dev; 509 device_set_wakeup_capable(&lid_switch_idev->dev, true); 510 511 r = input_register_device(lid_switch_idev); 512 if (r) { 513 dev_err(&pdev->dev, "failed to register lid switch: %d\n", r); 514 goto err_register; 515 } 516 517 r = device_create_file(&lid_switch_idev->dev, &dev_attr_lid_wake_mode); 518 if (r) { 519 dev_err(&pdev->dev, "failed to create wake mode attr: %d\n", r); 520 goto err_create_attr; 521 } 522 523 return 0; 524 525 err_create_attr: 526 input_unregister_device(lid_switch_idev); 527 lid_switch_idev = NULL; 528 err_register: 529 input_free_device(lid_switch_idev); 530 return r; 531 } 532 533 static void free_lid_switch(void) 534 { 535 device_remove_file(&lid_switch_idev->dev, &dev_attr_lid_wake_mode); 536 input_unregister_device(lid_switch_idev); 537 } 538 539 static int xo1_sci_probe(struct platform_device *pdev) 540 { 541 struct resource *res; 542 int r; 543 544 /* don't run on non-XOs */ 545 if (!machine_is_olpc()) 546 return -ENODEV; 547 548 r = mfd_cell_enable(pdev); 549 if (r) 550 return r; 551 552 res = platform_get_resource(pdev, IORESOURCE_IO, 0); 553 if (!res) { 554 dev_err(&pdev->dev, "can't fetch device resource info\n"); 555 return -EIO; 556 } 557 acpi_base = res->start; 558 559 r = setup_power_button(pdev); 560 if (r) 561 return r; 562 563 r = setup_ebook_switch(pdev); 564 if (r) 565 goto err_ebook; 566 567 r = setup_lid_switch(pdev); 568 if (r) 569 goto err_lid; 570 571 r = setup_lid_events(); 572 if (r) 573 goto err_lidevt; 574 575 r = setup_ec_sci(); 576 if (r) 577 goto err_ecsci; 578 579 /* Enable PME generation for EC-generated events */ 580 outl(CS5536_GPIOM6_PME_EN | CS5536_GPIOM7_PME_EN, 581 acpi_base + CS5536_PM_GPE0_EN); 582 583 /* Clear pending events */ 584 outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS); 585 process_sci_queue(false); 586 587 /* Initial sync */ 588 send_ebook_state(); 589 detect_lid_state(); 590 send_lid_state(); 591 592 r = setup_sci_interrupt(pdev); 593 if (r) 594 goto err_sci; 595 596 /* Enable all EC events */ 597 olpc_ec_mask_write(EC_SCI_SRC_ALL); 598 599 return r; 600 601 err_sci: 602 free_ec_sci(); 603 err_ecsci: 604 free_lid_events(); 605 err_lidevt: 606 free_lid_switch(); 607 err_lid: 608 free_ebook_switch(); 609 err_ebook: 610 free_power_button(); 611 return r; 612 } 613 614 static int xo1_sci_remove(struct platform_device *pdev) 615 { 616 mfd_cell_disable(pdev); 617 free_irq(sci_irq, pdev); 618 cancel_work_sync(&sci_work); 619 free_ec_sci(); 620 free_lid_events(); 621 free_lid_switch(); 622 free_ebook_switch(); 623 free_power_button(); 624 acpi_base = 0; 625 return 0; 626 } 627 628 static struct platform_driver xo1_sci_driver = { 629 .driver = { 630 .name = "olpc-xo1-sci-acpi", 631 }, 632 .probe = xo1_sci_probe, 633 .remove = xo1_sci_remove, 634 .suspend = xo1_sci_suspend, 635 .resume = xo1_sci_resume, 636 }; 637 638 static int __init xo1_sci_init(void) 639 { 640 return platform_driver_register(&xo1_sci_driver); 641 } 642 arch_initcall(xo1_sci_init); 643