2 * Gmux driver for Apple laptops
4 * Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
5 * Copyright (C) 2010-2012 Andreas Heider <andreas@meetr.de>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/backlight.h>
18 #include <linux/acpi.h>
19 #include <linux/pnp.h>
20 #include <linux/apple_bl.h>
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/pci.h>
24 #include <linux/vga_switcheroo.h>
25 #include <acpi/video.h>
28 struct apple_gmux_data {
29 unsigned long iostart;
32 struct mutex index_lock;
34 struct backlight_device *bdev;
39 enum vga_switcheroo_client_id resume_client_id;
40 enum vga_switcheroo_state power_state;
41 struct completion powerchange_done;
44 static struct apple_gmux_data *apple_gmux_data;
47 * gmux port offsets. Many of these are not yet used, but may be in the
48 * future, and it's useful to have them documented here anyhow.
50 #define GMUX_PORT_VERSION_MAJOR 0x04
51 #define GMUX_PORT_VERSION_MINOR 0x05
52 #define GMUX_PORT_VERSION_RELEASE 0x06
53 #define GMUX_PORT_SWITCH_DISPLAY 0x10
54 #define GMUX_PORT_SWITCH_GET_DISPLAY 0x11
55 #define GMUX_PORT_INTERRUPT_ENABLE 0x14
56 #define GMUX_PORT_INTERRUPT_STATUS 0x16
57 #define GMUX_PORT_SWITCH_DDC 0x28
58 #define GMUX_PORT_SWITCH_EXTERNAL 0x40
59 #define GMUX_PORT_SWITCH_GET_EXTERNAL 0x41
60 #define GMUX_PORT_DISCRETE_POWER 0x50
61 #define GMUX_PORT_MAX_BRIGHTNESS 0x70
62 #define GMUX_PORT_BRIGHTNESS 0x74
63 #define GMUX_PORT_VALUE 0xc2
64 #define GMUX_PORT_READ 0xd0
65 #define GMUX_PORT_WRITE 0xd4
67 #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4)
69 #define GMUX_INTERRUPT_ENABLE 0xff
70 #define GMUX_INTERRUPT_DISABLE 0x00
72 #define GMUX_INTERRUPT_STATUS_ACTIVE 0
73 #define GMUX_INTERRUPT_STATUS_DISPLAY (1 << 0)
74 #define GMUX_INTERRUPT_STATUS_POWER (1 << 2)
75 #define GMUX_INTERRUPT_STATUS_HOTPLUG (1 << 3)
77 #define GMUX_BRIGHTNESS_MASK 0x00ffffff
78 #define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK
80 static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port)
82 return inb(gmux_data->iostart + port);
85 static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port,
88 outb(val, gmux_data->iostart + port);
91 static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port)
93 return inl(gmux_data->iostart + port);
96 static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port,
102 for (i = 0; i < 4; i++) {
103 tmpval = (val >> (i * 8)) & 0xff;
104 outb(tmpval, port + i);
108 static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data)
111 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
113 while (i && (gwr & 0x01)) {
114 inb(gmux_data->iostart + GMUX_PORT_READ);
115 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
123 static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data)
126 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
128 while (i && !(gwr & 0x01)) {
129 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
135 inb(gmux_data->iostart + GMUX_PORT_READ);
140 static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port)
144 mutex_lock(&gmux_data->index_lock);
145 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
146 gmux_index_wait_ready(gmux_data);
147 val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
148 mutex_unlock(&gmux_data->index_lock);
153 static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
156 mutex_lock(&gmux_data->index_lock);
157 outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
158 gmux_index_wait_ready(gmux_data);
159 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
160 gmux_index_wait_complete(gmux_data);
161 mutex_unlock(&gmux_data->index_lock);
164 static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
168 mutex_lock(&gmux_data->index_lock);
169 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
170 gmux_index_wait_ready(gmux_data);
171 val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
172 mutex_unlock(&gmux_data->index_lock);
177 static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
183 mutex_lock(&gmux_data->index_lock);
185 for (i = 0; i < 4; i++) {
186 tmpval = (val >> (i * 8)) & 0xff;
187 outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
190 gmux_index_wait_ready(gmux_data);
191 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
192 gmux_index_wait_complete(gmux_data);
193 mutex_unlock(&gmux_data->index_lock);
196 static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
198 if (gmux_data->indexed)
199 return gmux_index_read8(gmux_data, port);
201 return gmux_pio_read8(gmux_data, port);
204 static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
206 if (gmux_data->indexed)
207 gmux_index_write8(gmux_data, port, val);
209 gmux_pio_write8(gmux_data, port, val);
212 static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
214 if (gmux_data->indexed)
215 return gmux_index_read32(gmux_data, port);
217 return gmux_pio_read32(gmux_data, port);
220 static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
223 if (gmux_data->indexed)
224 gmux_index_write32(gmux_data, port, val);
226 gmux_pio_write32(gmux_data, port, val);
229 static bool gmux_is_indexed(struct apple_gmux_data *gmux_data)
233 outb(0xaa, gmux_data->iostart + 0xcc);
234 outb(0x55, gmux_data->iostart + 0xcd);
235 outb(0x00, gmux_data->iostart + 0xce);
237 val = inb(gmux_data->iostart + 0xcc) |
238 (inb(gmux_data->iostart + 0xcd) << 8);
246 static int gmux_get_brightness(struct backlight_device *bd)
248 struct apple_gmux_data *gmux_data = bl_get_data(bd);
249 return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
250 GMUX_BRIGHTNESS_MASK;
253 static int gmux_update_status(struct backlight_device *bd)
255 struct apple_gmux_data *gmux_data = bl_get_data(bd);
256 u32 brightness = bd->props.brightness;
258 if (bd->props.state & BL_CORE_SUSPENDED)
261 gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
266 static const struct backlight_ops gmux_bl_ops = {
267 .options = BL_CORE_SUSPENDRESUME,
268 .get_brightness = gmux_get_brightness,
269 .update_status = gmux_update_status,
272 static int gmux_switchto(enum vga_switcheroo_client_id id)
274 if (id == VGA_SWITCHEROO_IGD) {
275 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
276 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
277 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
279 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
280 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
281 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
287 static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
288 enum vga_switcheroo_state state)
290 INIT_COMPLETION(gmux_data->powerchange_done);
292 if (state == VGA_SWITCHEROO_ON) {
293 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
294 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
295 pr_debug("Discrete card powered up\n");
297 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
298 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
299 pr_debug("Discrete card powered down\n");
302 gmux_data->power_state = state;
304 if (gmux_data->gpe >= 0 &&
305 !wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
306 msecs_to_jiffies(200)))
307 pr_warn("Timeout waiting for gmux switch to complete\n");
312 static int gmux_set_power_state(enum vga_switcheroo_client_id id,
313 enum vga_switcheroo_state state)
315 if (id == VGA_SWITCHEROO_IGD)
318 return gmux_set_discrete_state(apple_gmux_data, state);
321 static int gmux_get_client_id(struct pci_dev *pdev)
324 * Early Macbook Pros with switchable graphics use nvidia
325 * integrated graphics. Hardcode that the 9400M is integrated.
327 if (pdev->vendor == PCI_VENDOR_ID_INTEL)
328 return VGA_SWITCHEROO_IGD;
329 else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
330 pdev->device == 0x0863)
331 return VGA_SWITCHEROO_IGD;
333 return VGA_SWITCHEROO_DIS;
336 static enum vga_switcheroo_client_id
337 gmux_active_client(struct apple_gmux_data *gmux_data)
339 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
340 return VGA_SWITCHEROO_IGD;
342 return VGA_SWITCHEROO_DIS;
345 static struct vga_switcheroo_handler gmux_handler = {
346 .switchto = gmux_switchto,
347 .power_state = gmux_set_power_state,
348 .get_client_id = gmux_get_client_id,
351 static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
353 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
354 GMUX_INTERRUPT_DISABLE);
357 static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
359 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
360 GMUX_INTERRUPT_ENABLE);
363 static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
365 return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
368 static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
372 /* to clear interrupts write back current status */
373 status = gmux_interrupt_get_status(gmux_data);
374 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
377 static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
380 struct pnp_dev *pnp = (struct pnp_dev *)context;
381 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
383 status = gmux_interrupt_get_status(gmux_data);
384 gmux_disable_interrupts(gmux_data);
385 pr_debug("Notify handler called: status %d\n", status);
387 gmux_clear_interrupts(gmux_data);
388 gmux_enable_interrupts(gmux_data);
390 if (status & GMUX_INTERRUPT_STATUS_POWER)
391 complete(&gmux_data->powerchange_done);
394 static int gmux_suspend(struct pnp_dev *pnp, pm_message_t state)
396 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
397 gmux_data->resume_client_id = gmux_active_client(gmux_data);
398 gmux_disable_interrupts(gmux_data);
402 static int gmux_resume(struct pnp_dev *pnp)
404 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
405 gmux_enable_interrupts(gmux_data);
406 gmux_switchto(gmux_data->resume_client_id);
407 if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
408 gmux_set_discrete_state(gmux_data, gmux_data->power_state);
412 static int __devinit gmux_probe(struct pnp_dev *pnp,
413 const struct pnp_device_id *id)
415 struct apple_gmux_data *gmux_data;
416 struct resource *res;
417 struct backlight_properties props;
418 struct backlight_device *bdev;
419 u8 ver_major, ver_minor, ver_release;
422 unsigned long long gpe;
427 gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
430 pnp_set_drvdata(pnp, gmux_data);
432 res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
434 pr_err("Failed to find gmux I/O resource\n");
438 gmux_data->iostart = res->start;
439 gmux_data->iolen = res->end - res->start;
441 if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
442 pr_err("gmux I/O region too small (%lu < %u)\n",
443 gmux_data->iolen, GMUX_MIN_IO_LEN);
447 if (!request_region(gmux_data->iostart, gmux_data->iolen,
449 pr_err("gmux I/O already in use\n");
454 * Invalid version information may indicate either that the gmux
455 * device isn't present or that it's a new one that uses indexed
459 ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
460 ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
461 ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
462 if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
463 if (gmux_is_indexed(gmux_data)) {
464 mutex_init(&gmux_data->index_lock);
465 gmux_data->indexed = true;
467 pr_info("gmux device not present\n");
471 pr_info("Found indexed gmux\n");
473 pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor,
477 memset(&props, 0, sizeof(props));
478 props.type = BACKLIGHT_PLATFORM;
479 props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
482 * Currently it's assumed that the maximum brightness is less than
483 * 2^24 for compatibility with old gmux versions. Cap the max
484 * brightness at this value, but print a warning if the hardware
485 * reports something higher so that it can be fixed.
487 if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
488 props.max_brightness = GMUX_MAX_BRIGHTNESS;
490 bdev = backlight_device_register("gmux_backlight", &pnp->dev,
491 gmux_data, &gmux_bl_ops, &props);
497 gmux_data->bdev = bdev;
498 bdev->props.brightness = gmux_get_brightness(bdev);
499 backlight_update_status(bdev);
502 * The backlight situation on Macs is complicated. If the gmux is
503 * present it's the best choice, because it always works for
504 * backlight control and supports more levels than other options.
505 * Disable the other backlight choices.
507 acpi_video_dmi_promote_vendor();
508 #if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE)
509 acpi_video_unregister();
511 apple_bl_unregister();
513 gmux_data->power_state = VGA_SWITCHEROO_ON;
515 gmux_data->dhandle = DEVICE_ACPI_HANDLE(&pnp->dev);
516 if (!gmux_data->dhandle) {
517 pr_err("Cannot find acpi handle for pnp device %s\n",
518 dev_name(&pnp->dev));
523 status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
524 if (ACPI_SUCCESS(status)) {
525 gmux_data->gpe = (int)gpe;
527 status = acpi_install_notify_handler(gmux_data->dhandle,
529 &gmux_notify_handler, pnp);
530 if (ACPI_FAILURE(status)) {
531 pr_err("Install notify handler failed: %s\n",
532 acpi_format_exception(status));
537 status = acpi_enable_gpe(NULL, gmux_data->gpe);
538 if (ACPI_FAILURE(status)) {
539 pr_err("Cannot enable gpe: %s\n",
540 acpi_format_exception(status));
544 pr_warn("No GPE found for gmux\n");
548 if (vga_switcheroo_register_handler(&gmux_handler)) {
550 goto err_register_handler;
553 init_completion(&gmux_data->powerchange_done);
554 apple_gmux_data = gmux_data;
555 gmux_enable_interrupts(gmux_data);
559 err_register_handler:
560 if (gmux_data->gpe >= 0)
561 acpi_disable_gpe(NULL, gmux_data->gpe);
563 if (gmux_data->gpe >= 0)
564 acpi_remove_notify_handler(gmux_data->dhandle,
566 &gmux_notify_handler);
568 backlight_device_unregister(bdev);
570 release_region(gmux_data->iostart, gmux_data->iolen);
576 static void __devexit gmux_remove(struct pnp_dev *pnp)
578 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
580 vga_switcheroo_unregister_handler();
581 gmux_disable_interrupts(gmux_data);
582 if (gmux_data->gpe >= 0) {
583 acpi_disable_gpe(NULL, gmux_data->gpe);
584 acpi_remove_notify_handler(gmux_data->dhandle,
586 &gmux_notify_handler);
589 backlight_device_unregister(gmux_data->bdev);
591 release_region(gmux_data->iostart, gmux_data->iolen);
592 apple_gmux_data = NULL;
595 acpi_video_dmi_demote_vendor();
596 #if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE)
597 acpi_video_register();
602 static const struct pnp_device_id gmux_device_ids[] = {
607 static struct pnp_driver gmux_pnp_driver = {
608 .name = "apple-gmux",
610 .remove = __devexit_p(gmux_remove),
611 .id_table = gmux_device_ids,
612 .suspend = gmux_suspend,
613 .resume = gmux_resume
616 static int __init apple_gmux_init(void)
618 return pnp_register_driver(&gmux_pnp_driver);
621 static void __exit apple_gmux_exit(void)
623 pnp_unregister_driver(&gmux_pnp_driver);
626 module_init(apple_gmux_init);
627 module_exit(apple_gmux_exit);
629 MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
630 MODULE_DESCRIPTION("Apple Gmux Driver");
631 MODULE_LICENSE("GPL");
632 MODULE_DEVICE_TABLE(pnp, gmux_device_ids);