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
battery_status_changed(void)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
ac_status_changed(void)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 */
send_ebook_state(void)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
flip_lid_inverter(void)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
detect_lid_state(void)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 anomoly: 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 */
send_lid_state(void)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
lid_wake_mode_show(struct device * dev,struct device_attribute * attr,char * buf)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 }
lid_wake_mode_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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 */
process_sci_queue(bool propagate_events)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
process_sci_queue_work(struct work_struct * work)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
xo1_sci_intr(int irq,void * dev_id)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
xo1_sci_suspend(struct platform_device * pdev,pm_message_t state)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
xo1_sci_resume(struct platform_device * pdev)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
setup_sci_interrupt(struct platform_device * pdev)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
setup_ec_sci(void)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
free_ec_sci(void)393 static void free_ec_sci(void)
394 {
395 gpio_free(OLPC_GPIO_ECSCI);
396 }
397
setup_lid_events(void)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
free_lid_events(void)430 static void free_lid_events(void)
431 {
432 gpio_free(OLPC_GPIO_LID);
433 }
434
setup_power_button(struct platform_device * pdev)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
free_power_button(void)460 static void free_power_button(void)
461 {
462 input_unregister_device(power_button_idev);
463 }
464
setup_ebook_switch(struct platform_device * pdev)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
free_ebook_switch(void)490 static void free_ebook_switch(void)
491 {
492 input_unregister_device(ebook_switch_idev);
493 }
494
setup_lid_switch(struct platform_device * pdev)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
free_lid_switch(void)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
xo1_sci_probe(struct platform_device * pdev)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
xo1_sci_remove(struct platform_device * pdev)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
xo1_sci_init(void)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