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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Gmux driver for Apple laptops
4 *
5 * Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
6 * Copyright (C) 2010-2012 Andreas Heider <andreas@meetr.de>
7 * Copyright (C) 2015 Lukas Wunner <lukas@wunner.de>
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/backlight.h>
16#include <linux/acpi.h>
17#include <linux/pnp.h>
18#include <linux/apple_bl.h>
19#include <linux/apple-gmux.h>
20#include <linux/slab.h>
21#include <linux/delay.h>
22#include <linux/pci.h>
23#include <linux/vga_switcheroo.h>
24#include <asm/io.h>
25
26/**
27 * DOC: Overview
28 *
29 * gmux is a microcontroller built into the MacBook Pro to support dual GPUs:
30 * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on retinas.
31 *
32 * (The MacPro6,1 2013 also has a gmux, however it is unclear why since it has
33 * dual GPUs but no built-in display.)
34 *
35 * gmux is connected to the LPC bus of the southbridge. Its I/O ports are
36 * accessed differently depending on the microcontroller: Driver functions
37 * to access a pre-retina gmux are infixed ``_pio_``, those for a retina gmux
38 * are infixed ``_index_``.
39 *
40 * .. _Lattice XP2:
41 * http://www.latticesemi.com/en/Products/FPGAandCPLD/LatticeXP2.aspx
42 * .. _Renesas R4F2113:
43 * http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jsp
44 */
45
46struct apple_gmux_data {
47 unsigned long iostart;
48 unsigned long iolen;
49 bool indexed;
50 struct mutex index_lock;
51
52 struct backlight_device *bdev;
53
54 /* switcheroo data */
55 acpi_handle dhandle;
56 int gpe;
57 bool external_switchable;
58 enum vga_switcheroo_client_id switch_state_display;
59 enum vga_switcheroo_client_id switch_state_ddc;
60 enum vga_switcheroo_client_id switch_state_external;
61 enum vga_switcheroo_state power_state;
62 struct completion powerchange_done;
63};
64
65static struct apple_gmux_data *apple_gmux_data;
66
67#define GMUX_INTERRUPT_ENABLE 0xff
68#define GMUX_INTERRUPT_DISABLE 0x00
69
70#define GMUX_INTERRUPT_STATUS_ACTIVE 0
71#define GMUX_INTERRUPT_STATUS_DISPLAY (1 << 0)
72#define GMUX_INTERRUPT_STATUS_POWER (1 << 2)
73#define GMUX_INTERRUPT_STATUS_HOTPLUG (1 << 3)
74
75#define GMUX_BRIGHTNESS_MASK 0x00ffffff
76#define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK
77
78static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port)
79{
80 return inb(gmux_data->iostart + port);
81}
82
83static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port,
84 u8 val)
85{
86 outb(val, gmux_data->iostart + port);
87}
88
89static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port)
90{
91 return inl(gmux_data->iostart + port);
92}
93
94static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port,
95 u32 val)
96{
97 int i;
98 u8 tmpval;
99
100 for (i = 0; i < 4; i++) {
101 tmpval = (val >> (i * 8)) & 0xff;
102 outb(tmpval, gmux_data->iostart + port + i);
103 }
104}
105
106static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data)
107{
108 int i = 200;
109 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
110
111 while (i && (gwr & 0x01)) {
112 inb(gmux_data->iostart + GMUX_PORT_READ);
113 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
114 udelay(100);
115 i--;
116 }
117
118 return !!i;
119}
120
121static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data)
122{
123 int i = 200;
124 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
125
126 while (i && !(gwr & 0x01)) {
127 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
128 udelay(100);
129 i--;
130 }
131
132 if (gwr & 0x01)
133 inb(gmux_data->iostart + GMUX_PORT_READ);
134
135 return !!i;
136}
137
138static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port)
139{
140 u8 val;
141
142 mutex_lock(&gmux_data->index_lock);
143 gmux_index_wait_ready(gmux_data);
144 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
145 gmux_index_wait_complete(gmux_data);
146 val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
147 mutex_unlock(&gmux_data->index_lock);
148
149 return val;
150}
151
152static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
153 u8 val)
154{
155 mutex_lock(&gmux_data->index_lock);
156 outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
157 gmux_index_wait_ready(gmux_data);
158 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
159 gmux_index_wait_complete(gmux_data);
160 mutex_unlock(&gmux_data->index_lock);
161}
162
163static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
164{
165 u32 val;
166
167 mutex_lock(&gmux_data->index_lock);
168 gmux_index_wait_ready(gmux_data);
169 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
170 gmux_index_wait_complete(gmux_data);
171 val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
172 mutex_unlock(&gmux_data->index_lock);
173
174 return val;
175}
176
177static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
178 u32 val)
179{
180 int i;
181 u8 tmpval;
182
183 mutex_lock(&gmux_data->index_lock);
184
185 for (i = 0; i < 4; i++) {
186 tmpval = (val >> (i * 8)) & 0xff;
187 outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
188 }
189
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);
194}
195
196static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
197{
198 if (gmux_data->indexed)
199 return gmux_index_read8(gmux_data, port);
200 else
201 return gmux_pio_read8(gmux_data, port);
202}
203
204static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
205{
206 if (gmux_data->indexed)
207 gmux_index_write8(gmux_data, port, val);
208 else
209 gmux_pio_write8(gmux_data, port, val);
210}
211
212static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
213{
214 if (gmux_data->indexed)
215 return gmux_index_read32(gmux_data, port);
216 else
217 return gmux_pio_read32(gmux_data, port);
218}
219
220static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
221 u32 val)
222{
223 if (gmux_data->indexed)
224 gmux_index_write32(gmux_data, port, val);
225 else
226 gmux_pio_write32(gmux_data, port, val);
227}
228
229/**
230 * DOC: Backlight control
231 *
232 * On single GPU MacBooks, the PWM signal for the backlight is generated by
233 * the GPU. On dual GPU MacBook Pros by contrast, either GPU may be suspended
234 * to conserve energy. Hence the PWM signal needs to be generated by a separate
235 * backlight driver which is controlled by gmux. The earliest generation
236 * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. All newer models
237 * use a `TI LP8545`_.
238 *
239 * .. _TI LP8543: https://www.ti.com/lit/ds/symlink/lp8543.pdf
240 * .. _TI LP8545: https://www.ti.com/lit/ds/symlink/lp8545.pdf
241 */
242
243static int gmux_get_brightness(struct backlight_device *bd)
244{
245 struct apple_gmux_data *gmux_data = bl_get_data(bd);
246 return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
247 GMUX_BRIGHTNESS_MASK;
248}
249
250static int gmux_update_status(struct backlight_device *bd)
251{
252 struct apple_gmux_data *gmux_data = bl_get_data(bd);
253 u32 brightness = backlight_get_brightness(bd);
254
255 gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
256
257 return 0;
258}
259
260static const struct backlight_ops gmux_bl_ops = {
261 .options = BL_CORE_SUSPENDRESUME,
262 .get_brightness = gmux_get_brightness,
263 .update_status = gmux_update_status,
264};
265
266/**
267 * DOC: Graphics mux
268 *
269 * On pre-retinas, the LVDS outputs of both GPUs feed into gmux which muxes
270 * either of them to the panel. One of the tricks gmux has up its sleeve is
271 * to lengthen the blanking interval of its output during a switch to
272 * synchronize it with the GPU switched to. This allows for a flicker-free
273 * switch that is imperceptible by the user (`US 8,687,007 B2`_).
274 *
275 * On retinas, muxing is no longer done by gmux itself, but by a separate
276 * chip which is controlled by gmux. The chip is triple sourced, it is
277 * either an `NXP CBTL06142`_, `TI HD3SS212`_ or `Pericom PI3VDP12412`_.
278 * The panel is driven with eDP instead of LVDS since the pixel clock
279 * required for retina resolution exceeds LVDS' limits.
280 *
281 * Pre-retinas are able to switch the panel's DDC pins separately.
282 * This is handled by a `TI SN74LV4066A`_ which is controlled by gmux.
283 * The inactive GPU can thus probe the panel's EDID without switching over
284 * the entire panel. Retinas lack this functionality as the chips used for
285 * eDP muxing are incapable of switching the AUX channel separately (see
286 * the linked data sheets, Pericom would be capable but this is unused).
287 * However the retina panel has the NO_AUX_HANDSHAKE_LINK_TRAINING bit set
288 * in its DPCD, allowing the inactive GPU to skip the AUX handshake and
289 * set up the output with link parameters pre-calibrated by the active GPU.
290 *
291 * The external DP port is only fully switchable on the first two unibody
292 * MacBook Pro generations, MBP5 2008/09 and MBP6 2010. This is done by an
293 * `NXP CBTL06141`_ which is controlled by gmux. It's the predecessor of the
294 * eDP mux on retinas, the difference being support for 2.7 versus 5.4 Gbit/s.
295 *
296 * The following MacBook Pro generations replaced the external DP port with a
297 * combined DP/Thunderbolt port and lost the ability to switch it between GPUs,
298 * connecting it either to the discrete GPU or the Thunderbolt controller.
299 * Oddly enough, while the full port is no longer switchable, AUX and HPD
300 * are still switchable by way of an `NXP CBTL03062`_ (on pre-retinas
301 * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on retinas) under the
302 * control of gmux. Since the integrated GPU is missing the main link,
303 * external displays appear to it as phantoms which fail to link-train.
304 *
305 * gmux receives the HPD signal of all display connectors and sends an
306 * interrupt on hotplug. On generations which cannot switch external ports,
307 * the discrete GPU can then be woken to drive the newly connected display.
308 * The ability to switch AUX on these generations could be used to improve
309 * reliability of hotplug detection by having the integrated GPU poll the
310 * ports while the discrete GPU is asleep, but currently we do not make use
311 * of this feature.
312 *
313 * Our switching policy for the external port is that on those generations
314 * which are able to switch it fully, the port is switched together with the
315 * panel when IGD / DIS commands are issued to vga_switcheroo. It is thus
316 * possible to drive e.g. a beamer on battery power with the integrated GPU.
317 * The user may manually switch to the discrete GPU if more performance is
318 * needed.
319 *
320 * On all newer generations, the external port can only be driven by the
321 * discrete GPU. If a display is plugged in while the panel is switched to
322 * the integrated GPU, *both* GPUs will be in use for maximum performance.
323 * To decrease power consumption, the user may manually switch to the
324 * discrete GPU, thereby suspending the integrated GPU.
325 *
326 * gmux' initial switch state on bootup is user configurable via the EFI
327 * variable ``gpu-power-prefs-fa4ce28d-b62f-4c99-9cc3-6815686e30f9`` (5th byte,
328 * 1 = IGD, 0 = DIS). Based on this setting, the EFI firmware tells gmux to
329 * switch the panel and the external DP connector and allocates a framebuffer
330 * for the selected GPU.
331 *
332 * .. _US 8,687,007 B2: https://pimg-fpiw.uspto.gov/fdd/07/870/086/0.pdf
333 * .. _NXP CBTL06141: https://www.nxp.com/documents/data_sheet/CBTL06141.pdf
334 * .. _NXP CBTL06142: https://www.nxp.com/documents/data_sheet/CBTL06141.pdf
335 * .. _TI HD3SS212: https://www.ti.com/lit/ds/symlink/hd3ss212.pdf
336 * .. _Pericom PI3VDP12412: https://www.pericom.com/assets/Datasheets/PI3VDP12412.pdf
337 * .. _TI SN74LV4066A: https://www.ti.com/lit/ds/symlink/sn74lv4066a.pdf
338 * .. _NXP CBTL03062: http://pdf.datasheetarchive.com/indexerfiles/Datasheets-SW16/DSASW00308511.pdf
339 * .. _TI TS3DS10224: https://www.ti.com/lit/ds/symlink/ts3ds10224.pdf
340 */
341
342static void gmux_read_switch_state(struct apple_gmux_data *gmux_data)
343{
344 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DDC) == 1)
345 gmux_data->switch_state_ddc = VGA_SWITCHEROO_IGD;
346 else
347 gmux_data->switch_state_ddc = VGA_SWITCHEROO_DIS;
348
349 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
350 gmux_data->switch_state_display = VGA_SWITCHEROO_IGD;
351 else
352 gmux_data->switch_state_display = VGA_SWITCHEROO_DIS;
353
354 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL) == 2)
355 gmux_data->switch_state_external = VGA_SWITCHEROO_IGD;
356 else
357 gmux_data->switch_state_external = VGA_SWITCHEROO_DIS;
358}
359
360static void gmux_write_switch_state(struct apple_gmux_data *gmux_data)
361{
362 if (gmux_data->switch_state_ddc == VGA_SWITCHEROO_IGD)
363 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DDC, 1);
364 else
365 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DDC, 2);
366
367 if (gmux_data->switch_state_display == VGA_SWITCHEROO_IGD)
368 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
369 else
370 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
371
372 if (gmux_data->switch_state_external == VGA_SWITCHEROO_IGD)
373 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
374 else
375 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
376}
377
378static int gmux_switchto(enum vga_switcheroo_client_id id)
379{
380 apple_gmux_data->switch_state_ddc = id;
381 apple_gmux_data->switch_state_display = id;
382 if (apple_gmux_data->external_switchable)
383 apple_gmux_data->switch_state_external = id;
384
385 gmux_write_switch_state(apple_gmux_data);
386
387 return 0;
388}
389
390static int gmux_switch_ddc(enum vga_switcheroo_client_id id)
391{
392 enum vga_switcheroo_client_id old_ddc_owner =
393 apple_gmux_data->switch_state_ddc;
394
395 if (id == old_ddc_owner)
396 return id;
397
398 pr_debug("Switching DDC from %d to %d\n", old_ddc_owner, id);
399 apple_gmux_data->switch_state_ddc = id;
400
401 if (id == VGA_SWITCHEROO_IGD)
402 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
403 else
404 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
405
406 return old_ddc_owner;
407}
408
409/**
410 * DOC: Power control
411 *
412 * gmux is able to cut power to the discrete GPU. It automatically takes care
413 * of the correct sequence to tear down and bring up the power rails for
414 * core voltage, VRAM and PCIe.
415 */
416
417static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
418 enum vga_switcheroo_state state)
419{
420 reinit_completion(&gmux_data->powerchange_done);
421
422 if (state == VGA_SWITCHEROO_ON) {
423 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
424 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
425 pr_debug("Discrete card powered up\n");
426 } else {
427 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
428 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
429 pr_debug("Discrete card powered down\n");
430 }
431
432 gmux_data->power_state = state;
433
434 if (gmux_data->gpe >= 0 &&
435 !wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
436 msecs_to_jiffies(200)))
437 pr_warn("Timeout waiting for gmux switch to complete\n");
438
439 return 0;
440}
441
442static int gmux_set_power_state(enum vga_switcheroo_client_id id,
443 enum vga_switcheroo_state state)
444{
445 if (id == VGA_SWITCHEROO_IGD)
446 return 0;
447
448 return gmux_set_discrete_state(apple_gmux_data, state);
449}
450
451static enum vga_switcheroo_client_id gmux_get_client_id(struct pci_dev *pdev)
452{
453 /*
454 * Early Macbook Pros with switchable graphics use nvidia
455 * integrated graphics. Hardcode that the 9400M is integrated.
456 */
457 if (pdev->vendor == PCI_VENDOR_ID_INTEL)
458 return VGA_SWITCHEROO_IGD;
459 else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
460 pdev->device == 0x0863)
461 return VGA_SWITCHEROO_IGD;
462 else
463 return VGA_SWITCHEROO_DIS;
464}
465
466static const struct vga_switcheroo_handler gmux_handler_indexed = {
467 .switchto = gmux_switchto,
468 .power_state = gmux_set_power_state,
469 .get_client_id = gmux_get_client_id,
470};
471
472static const struct vga_switcheroo_handler gmux_handler_classic = {
473 .switchto = gmux_switchto,
474 .switch_ddc = gmux_switch_ddc,
475 .power_state = gmux_set_power_state,
476 .get_client_id = gmux_get_client_id,
477};
478
479/**
480 * DOC: Interrupt
481 *
482 * gmux is also connected to a GPIO pin of the southbridge and thereby is able
483 * to trigger an ACPI GPE. On the MBP5 2008/09 it's GPIO pin 22 of the Nvidia
484 * MCP79, on all following generations it's GPIO pin 6 of the Intel PCH.
485 * The GPE merely signals that an interrupt occurred, the actual type of event
486 * is identified by reading a gmux register.
487 */
488
489static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
490{
491 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
492 GMUX_INTERRUPT_DISABLE);
493}
494
495static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
496{
497 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
498 GMUX_INTERRUPT_ENABLE);
499}
500
501static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
502{
503 return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
504}
505
506static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
507{
508 u8 status;
509
510 /* to clear interrupts write back current status */
511 status = gmux_interrupt_get_status(gmux_data);
512 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
513}
514
515static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
516{
517 u8 status;
518 struct pnp_dev *pnp = (struct pnp_dev *)context;
519 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
520
521 status = gmux_interrupt_get_status(gmux_data);
522 gmux_disable_interrupts(gmux_data);
523 pr_debug("Notify handler called: status %d\n", status);
524
525 gmux_clear_interrupts(gmux_data);
526 gmux_enable_interrupts(gmux_data);
527
528 if (status & GMUX_INTERRUPT_STATUS_POWER)
529 complete(&gmux_data->powerchange_done);
530}
531
532static int gmux_suspend(struct device *dev)
533{
534 struct pnp_dev *pnp = to_pnp_dev(dev);
535 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
536
537 gmux_disable_interrupts(gmux_data);
538 return 0;
539}
540
541static int gmux_resume(struct device *dev)
542{
543 struct pnp_dev *pnp = to_pnp_dev(dev);
544 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
545
546 gmux_enable_interrupts(gmux_data);
547 gmux_write_switch_state(gmux_data);
548 if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
549 gmux_set_discrete_state(gmux_data, gmux_data->power_state);
550 return 0;
551}
552
553static int is_thunderbolt(struct device *dev, void *data)
554{
555 return to_pci_dev(dev)->is_thunderbolt;
556}
557
558static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
559{
560 struct apple_gmux_data *gmux_data;
561 struct resource *res;
562 struct backlight_properties props;
563 struct backlight_device *bdev;
564 u8 ver_major, ver_minor, ver_release;
565 int ret = -ENXIO;
566 acpi_status status;
567 unsigned long long gpe;
568 bool indexed = false;
569 u32 version;
570
571 if (apple_gmux_data)
572 return -EBUSY;
573
574 if (!apple_gmux_detect(pnp, &indexed)) {
575 pr_info("gmux device not present\n");
576 return -ENODEV;
577 }
578
579 gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
580 if (!gmux_data)
581 return -ENOMEM;
582 pnp_set_drvdata(pnp, gmux_data);
583
584 res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
585 gmux_data->iostart = res->start;
586 gmux_data->iolen = resource_size(res);
587
588 if (!request_region(gmux_data->iostart, gmux_data->iolen,
589 "Apple gmux")) {
590 pr_err("gmux I/O already in use\n");
591 goto err_free;
592 }
593
594 if (indexed) {
595 mutex_init(&gmux_data->index_lock);
596 gmux_data->indexed = true;
597 version = gmux_read32(gmux_data, GMUX_PORT_VERSION_MAJOR);
598 ver_major = (version >> 24) & 0xff;
599 ver_minor = (version >> 16) & 0xff;
600 ver_release = (version >> 8) & 0xff;
601 } else {
602 ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
603 ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
604 ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
605 }
606 pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor,
607 ver_release, (gmux_data->indexed ? "indexed" : "classic"));
608
609 memset(&props, 0, sizeof(props));
610 props.type = BACKLIGHT_PLATFORM;
611 props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
612
613 /*
614 * Currently it's assumed that the maximum brightness is less than
615 * 2^24 for compatibility with old gmux versions. Cap the max
616 * brightness at this value, but print a warning if the hardware
617 * reports something higher so that it can be fixed.
618 */
619 if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
620 props.max_brightness = GMUX_MAX_BRIGHTNESS;
621
622 bdev = backlight_device_register("gmux_backlight", &pnp->dev,
623 gmux_data, &gmux_bl_ops, &props);
624 if (IS_ERR(bdev)) {
625 ret = PTR_ERR(bdev);
626 goto err_release;
627 }
628
629 gmux_data->bdev = bdev;
630 bdev->props.brightness = gmux_get_brightness(bdev);
631 backlight_update_status(bdev);
632
633 /*
634 * The backlight situation on Macs is complicated. If the gmux is
635 * present it's the best choice, because it always works for
636 * backlight control and supports more levels than other options.
637 * Disable the other backlight choices.
638 */
639 apple_bl_unregister();
640
641 gmux_data->power_state = VGA_SWITCHEROO_ON;
642
643 gmux_data->dhandle = ACPI_HANDLE(&pnp->dev);
644 if (!gmux_data->dhandle) {
645 pr_err("Cannot find acpi handle for pnp device %s\n",
646 dev_name(&pnp->dev));
647 ret = -ENODEV;
648 goto err_notify;
649 }
650
651 status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
652 if (ACPI_SUCCESS(status)) {
653 gmux_data->gpe = (int)gpe;
654
655 status = acpi_install_notify_handler(gmux_data->dhandle,
656 ACPI_DEVICE_NOTIFY,
657 &gmux_notify_handler, pnp);
658 if (ACPI_FAILURE(status)) {
659 pr_err("Install notify handler failed: %s\n",
660 acpi_format_exception(status));
661 ret = -ENODEV;
662 goto err_notify;
663 }
664
665 status = acpi_enable_gpe(NULL, gmux_data->gpe);
666 if (ACPI_FAILURE(status)) {
667 pr_err("Cannot enable gpe: %s\n",
668 acpi_format_exception(status));
669 goto err_enable_gpe;
670 }
671 } else {
672 pr_warn("No GPE found for gmux\n");
673 gmux_data->gpe = -1;
674 }
675
676 /*
677 * If Thunderbolt is present, the external DP port is not fully
678 * switchable. Force its AUX channel to the discrete GPU.
679 */
680 gmux_data->external_switchable =
681 !bus_for_each_dev(&pci_bus_type, NULL, NULL, is_thunderbolt);
682 if (!gmux_data->external_switchable)
683 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
684
685 apple_gmux_data = gmux_data;
686 init_completion(&gmux_data->powerchange_done);
687 gmux_enable_interrupts(gmux_data);
688 gmux_read_switch_state(gmux_data);
689
690 /*
691 * Retina MacBook Pros cannot switch the panel's AUX separately
692 * and need eDP pre-calibration. They are distinguishable from
693 * pre-retinas by having an "indexed" gmux.
694 *
695 * Pre-retina MacBook Pros can switch the panel's DDC separately.
696 */
697 if (gmux_data->indexed)
698 ret = vga_switcheroo_register_handler(&gmux_handler_indexed,
699 VGA_SWITCHEROO_NEEDS_EDP_CONFIG);
700 else
701 ret = vga_switcheroo_register_handler(&gmux_handler_classic,
702 VGA_SWITCHEROO_CAN_SWITCH_DDC);
703 if (ret) {
704 pr_err("Failed to register vga_switcheroo handler\n");
705 goto err_register_handler;
706 }
707
708 return 0;
709
710err_register_handler:
711 gmux_disable_interrupts(gmux_data);
712 apple_gmux_data = NULL;
713 if (gmux_data->gpe >= 0)
714 acpi_disable_gpe(NULL, gmux_data->gpe);
715err_enable_gpe:
716 if (gmux_data->gpe >= 0)
717 acpi_remove_notify_handler(gmux_data->dhandle,
718 ACPI_DEVICE_NOTIFY,
719 &gmux_notify_handler);
720err_notify:
721 backlight_device_unregister(bdev);
722err_release:
723 release_region(gmux_data->iostart, gmux_data->iolen);
724err_free:
725 kfree(gmux_data);
726 return ret;
727}
728
729static void gmux_remove(struct pnp_dev *pnp)
730{
731 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
732
733 vga_switcheroo_unregister_handler();
734 gmux_disable_interrupts(gmux_data);
735 if (gmux_data->gpe >= 0) {
736 acpi_disable_gpe(NULL, gmux_data->gpe);
737 acpi_remove_notify_handler(gmux_data->dhandle,
738 ACPI_DEVICE_NOTIFY,
739 &gmux_notify_handler);
740 }
741
742 backlight_device_unregister(gmux_data->bdev);
743
744 release_region(gmux_data->iostart, gmux_data->iolen);
745 apple_gmux_data = NULL;
746 kfree(gmux_data);
747
748 apple_bl_register();
749}
750
751static const struct pnp_device_id gmux_device_ids[] = {
752 {GMUX_ACPI_HID, 0},
753 {"", 0}
754};
755
756static const struct dev_pm_ops gmux_dev_pm_ops = {
757 .suspend = gmux_suspend,
758 .resume = gmux_resume,
759};
760
761static struct pnp_driver gmux_pnp_driver = {
762 .name = "apple-gmux",
763 .probe = gmux_probe,
764 .remove = gmux_remove,
765 .id_table = gmux_device_ids,
766 .driver = {
767 .pm = &gmux_dev_pm_ops,
768 },
769};
770
771module_pnp_driver(gmux_pnp_driver);
772MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
773MODULE_DESCRIPTION("Apple Gmux Driver");
774MODULE_LICENSE("GPL");
775MODULE_DEVICE_TABLE(pnp, gmux_device_ids);
1/*
2 * Gmux driver for Apple laptops
3 *
4 * Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
5 * Copyright (C) 2010-2012 Andreas Heider <andreas@meetr.de>
6 *
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.
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
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>
26#include <asm/io.h>
27
28struct apple_gmux_data {
29 unsigned long iostart;
30 unsigned long iolen;
31 bool indexed;
32 struct mutex index_lock;
33
34 struct backlight_device *bdev;
35
36 /* switcheroo data */
37 acpi_handle dhandle;
38 int gpe;
39 enum vga_switcheroo_client_id resume_client_id;
40 enum vga_switcheroo_state power_state;
41 struct completion powerchange_done;
42};
43
44static struct apple_gmux_data *apple_gmux_data;
45
46/*
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.
49 */
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
66
67#define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4)
68
69#define GMUX_INTERRUPT_ENABLE 0xff
70#define GMUX_INTERRUPT_DISABLE 0x00
71
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)
76
77#define GMUX_BRIGHTNESS_MASK 0x00ffffff
78#define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK
79
80static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port)
81{
82 return inb(gmux_data->iostart + port);
83}
84
85static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port,
86 u8 val)
87{
88 outb(val, gmux_data->iostart + port);
89}
90
91static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port)
92{
93 return inl(gmux_data->iostart + port);
94}
95
96static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port,
97 u32 val)
98{
99 int i;
100 u8 tmpval;
101
102 for (i = 0; i < 4; i++) {
103 tmpval = (val >> (i * 8)) & 0xff;
104 outb(tmpval, gmux_data->iostart + port + i);
105 }
106}
107
108static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data)
109{
110 int i = 200;
111 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
112
113 while (i && (gwr & 0x01)) {
114 inb(gmux_data->iostart + GMUX_PORT_READ);
115 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
116 udelay(100);
117 i--;
118 }
119
120 return !!i;
121}
122
123static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data)
124{
125 int i = 200;
126 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
127
128 while (i && !(gwr & 0x01)) {
129 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE);
130 udelay(100);
131 i--;
132 }
133
134 if (gwr & 0x01)
135 inb(gmux_data->iostart + GMUX_PORT_READ);
136
137 return !!i;
138}
139
140static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port)
141{
142 u8 val;
143
144 mutex_lock(&gmux_data->index_lock);
145 gmux_index_wait_ready(gmux_data);
146 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
147 gmux_index_wait_complete(gmux_data);
148 val = inb(gmux_data->iostart + GMUX_PORT_VALUE);
149 mutex_unlock(&gmux_data->index_lock);
150
151 return val;
152}
153
154static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port,
155 u8 val)
156{
157 mutex_lock(&gmux_data->index_lock);
158 outb(val, gmux_data->iostart + GMUX_PORT_VALUE);
159 gmux_index_wait_ready(gmux_data);
160 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
161 gmux_index_wait_complete(gmux_data);
162 mutex_unlock(&gmux_data->index_lock);
163}
164
165static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port)
166{
167 u32 val;
168
169 mutex_lock(&gmux_data->index_lock);
170 gmux_index_wait_ready(gmux_data);
171 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ);
172 gmux_index_wait_complete(gmux_data);
173 val = inl(gmux_data->iostart + GMUX_PORT_VALUE);
174 mutex_unlock(&gmux_data->index_lock);
175
176 return val;
177}
178
179static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port,
180 u32 val)
181{
182 int i;
183 u8 tmpval;
184
185 mutex_lock(&gmux_data->index_lock);
186
187 for (i = 0; i < 4; i++) {
188 tmpval = (val >> (i * 8)) & 0xff;
189 outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i);
190 }
191
192 gmux_index_wait_ready(gmux_data);
193 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE);
194 gmux_index_wait_complete(gmux_data);
195 mutex_unlock(&gmux_data->index_lock);
196}
197
198static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
199{
200 if (gmux_data->indexed)
201 return gmux_index_read8(gmux_data, port);
202 else
203 return gmux_pio_read8(gmux_data, port);
204}
205
206static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val)
207{
208 if (gmux_data->indexed)
209 gmux_index_write8(gmux_data, port, val);
210 else
211 gmux_pio_write8(gmux_data, port, val);
212}
213
214static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
215{
216 if (gmux_data->indexed)
217 return gmux_index_read32(gmux_data, port);
218 else
219 return gmux_pio_read32(gmux_data, port);
220}
221
222static void gmux_write32(struct apple_gmux_data *gmux_data, int port,
223 u32 val)
224{
225 if (gmux_data->indexed)
226 gmux_index_write32(gmux_data, port, val);
227 else
228 gmux_pio_write32(gmux_data, port, val);
229}
230
231static bool gmux_is_indexed(struct apple_gmux_data *gmux_data)
232{
233 u16 val;
234
235 outb(0xaa, gmux_data->iostart + 0xcc);
236 outb(0x55, gmux_data->iostart + 0xcd);
237 outb(0x00, gmux_data->iostart + 0xce);
238
239 val = inb(gmux_data->iostart + 0xcc) |
240 (inb(gmux_data->iostart + 0xcd) << 8);
241
242 if (val == 0x55aa)
243 return true;
244
245 return false;
246}
247
248static int gmux_get_brightness(struct backlight_device *bd)
249{
250 struct apple_gmux_data *gmux_data = bl_get_data(bd);
251 return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
252 GMUX_BRIGHTNESS_MASK;
253}
254
255static int gmux_update_status(struct backlight_device *bd)
256{
257 struct apple_gmux_data *gmux_data = bl_get_data(bd);
258 u32 brightness = bd->props.brightness;
259
260 if (bd->props.state & BL_CORE_SUSPENDED)
261 return 0;
262
263 gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
264
265 return 0;
266}
267
268static const struct backlight_ops gmux_bl_ops = {
269 .options = BL_CORE_SUSPENDRESUME,
270 .get_brightness = gmux_get_brightness,
271 .update_status = gmux_update_status,
272};
273
274static int gmux_switchto(enum vga_switcheroo_client_id id)
275{
276 if (id == VGA_SWITCHEROO_IGD) {
277 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1);
278 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2);
279 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2);
280 } else {
281 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2);
282 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3);
283 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3);
284 }
285
286 return 0;
287}
288
289static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data,
290 enum vga_switcheroo_state state)
291{
292 reinit_completion(&gmux_data->powerchange_done);
293
294 if (state == VGA_SWITCHEROO_ON) {
295 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
296 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3);
297 pr_debug("Discrete card powered up\n");
298 } else {
299 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1);
300 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0);
301 pr_debug("Discrete card powered down\n");
302 }
303
304 gmux_data->power_state = state;
305
306 if (gmux_data->gpe >= 0 &&
307 !wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done,
308 msecs_to_jiffies(200)))
309 pr_warn("Timeout waiting for gmux switch to complete\n");
310
311 return 0;
312}
313
314static int gmux_set_power_state(enum vga_switcheroo_client_id id,
315 enum vga_switcheroo_state state)
316{
317 if (id == VGA_SWITCHEROO_IGD)
318 return 0;
319
320 return gmux_set_discrete_state(apple_gmux_data, state);
321}
322
323static int gmux_get_client_id(struct pci_dev *pdev)
324{
325 /*
326 * Early Macbook Pros with switchable graphics use nvidia
327 * integrated graphics. Hardcode that the 9400M is integrated.
328 */
329 if (pdev->vendor == PCI_VENDOR_ID_INTEL)
330 return VGA_SWITCHEROO_IGD;
331 else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
332 pdev->device == 0x0863)
333 return VGA_SWITCHEROO_IGD;
334 else
335 return VGA_SWITCHEROO_DIS;
336}
337
338static enum vga_switcheroo_client_id
339gmux_active_client(struct apple_gmux_data *gmux_data)
340{
341 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2)
342 return VGA_SWITCHEROO_IGD;
343
344 return VGA_SWITCHEROO_DIS;
345}
346
347static struct vga_switcheroo_handler gmux_handler = {
348 .switchto = gmux_switchto,
349 .power_state = gmux_set_power_state,
350 .get_client_id = gmux_get_client_id,
351};
352
353static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data)
354{
355 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
356 GMUX_INTERRUPT_DISABLE);
357}
358
359static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data)
360{
361 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE,
362 GMUX_INTERRUPT_ENABLE);
363}
364
365static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data)
366{
367 return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS);
368}
369
370static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data)
371{
372 u8 status;
373
374 /* to clear interrupts write back current status */
375 status = gmux_interrupt_get_status(gmux_data);
376 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status);
377}
378
379static void gmux_notify_handler(acpi_handle device, u32 value, void *context)
380{
381 u8 status;
382 struct pnp_dev *pnp = (struct pnp_dev *)context;
383 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
384
385 status = gmux_interrupt_get_status(gmux_data);
386 gmux_disable_interrupts(gmux_data);
387 pr_debug("Notify handler called: status %d\n", status);
388
389 gmux_clear_interrupts(gmux_data);
390 gmux_enable_interrupts(gmux_data);
391
392 if (status & GMUX_INTERRUPT_STATUS_POWER)
393 complete(&gmux_data->powerchange_done);
394}
395
396static int gmux_suspend(struct device *dev)
397{
398 struct pnp_dev *pnp = to_pnp_dev(dev);
399 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
400
401 gmux_data->resume_client_id = gmux_active_client(gmux_data);
402 gmux_disable_interrupts(gmux_data);
403 return 0;
404}
405
406static int gmux_resume(struct device *dev)
407{
408 struct pnp_dev *pnp = to_pnp_dev(dev);
409 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
410
411 gmux_enable_interrupts(gmux_data);
412 gmux_switchto(gmux_data->resume_client_id);
413 if (gmux_data->power_state == VGA_SWITCHEROO_OFF)
414 gmux_set_discrete_state(gmux_data, gmux_data->power_state);
415 return 0;
416}
417
418static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
419{
420 struct apple_gmux_data *gmux_data;
421 struct resource *res;
422 struct backlight_properties props;
423 struct backlight_device *bdev;
424 u8 ver_major, ver_minor, ver_release;
425 int ret = -ENXIO;
426 acpi_status status;
427 unsigned long long gpe;
428
429 if (apple_gmux_data)
430 return -EBUSY;
431
432 gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
433 if (!gmux_data)
434 return -ENOMEM;
435 pnp_set_drvdata(pnp, gmux_data);
436
437 res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
438 if (!res) {
439 pr_err("Failed to find gmux I/O resource\n");
440 goto err_free;
441 }
442
443 gmux_data->iostart = res->start;
444 gmux_data->iolen = res->end - res->start;
445
446 if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
447 pr_err("gmux I/O region too small (%lu < %u)\n",
448 gmux_data->iolen, GMUX_MIN_IO_LEN);
449 goto err_free;
450 }
451
452 if (!request_region(gmux_data->iostart, gmux_data->iolen,
453 "Apple gmux")) {
454 pr_err("gmux I/O already in use\n");
455 goto err_free;
456 }
457
458 /*
459 * Invalid version information may indicate either that the gmux
460 * device isn't present or that it's a new one that uses indexed
461 * io
462 */
463
464 ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
465 ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
466 ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
467 if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
468 if (gmux_is_indexed(gmux_data)) {
469 u32 version;
470 mutex_init(&gmux_data->index_lock);
471 gmux_data->indexed = true;
472 version = gmux_read32(gmux_data,
473 GMUX_PORT_VERSION_MAJOR);
474 ver_major = (version >> 24) & 0xff;
475 ver_minor = (version >> 16) & 0xff;
476 ver_release = (version >> 8) & 0xff;
477 } else {
478 pr_info("gmux device not present\n");
479 ret = -ENODEV;
480 goto err_release;
481 }
482 }
483 pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor,
484 ver_release, (gmux_data->indexed ? "indexed" : "classic"));
485
486 memset(&props, 0, sizeof(props));
487 props.type = BACKLIGHT_PLATFORM;
488 props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
489
490 /*
491 * Currently it's assumed that the maximum brightness is less than
492 * 2^24 for compatibility with old gmux versions. Cap the max
493 * brightness at this value, but print a warning if the hardware
494 * reports something higher so that it can be fixed.
495 */
496 if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
497 props.max_brightness = GMUX_MAX_BRIGHTNESS;
498
499 bdev = backlight_device_register("gmux_backlight", &pnp->dev,
500 gmux_data, &gmux_bl_ops, &props);
501 if (IS_ERR(bdev)) {
502 ret = PTR_ERR(bdev);
503 goto err_release;
504 }
505
506 gmux_data->bdev = bdev;
507 bdev->props.brightness = gmux_get_brightness(bdev);
508 backlight_update_status(bdev);
509
510 /*
511 * The backlight situation on Macs is complicated. If the gmux is
512 * present it's the best choice, because it always works for
513 * backlight control and supports more levels than other options.
514 * Disable the other backlight choices.
515 */
516 acpi_video_dmi_promote_vendor();
517 acpi_video_unregister();
518 apple_bl_unregister();
519
520 gmux_data->power_state = VGA_SWITCHEROO_ON;
521
522 gmux_data->dhandle = ACPI_HANDLE(&pnp->dev);
523 if (!gmux_data->dhandle) {
524 pr_err("Cannot find acpi handle for pnp device %s\n",
525 dev_name(&pnp->dev));
526 ret = -ENODEV;
527 goto err_notify;
528 }
529
530 status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe);
531 if (ACPI_SUCCESS(status)) {
532 gmux_data->gpe = (int)gpe;
533
534 status = acpi_install_notify_handler(gmux_data->dhandle,
535 ACPI_DEVICE_NOTIFY,
536 &gmux_notify_handler, pnp);
537 if (ACPI_FAILURE(status)) {
538 pr_err("Install notify handler failed: %s\n",
539 acpi_format_exception(status));
540 ret = -ENODEV;
541 goto err_notify;
542 }
543
544 status = acpi_enable_gpe(NULL, gmux_data->gpe);
545 if (ACPI_FAILURE(status)) {
546 pr_err("Cannot enable gpe: %s\n",
547 acpi_format_exception(status));
548 goto err_enable_gpe;
549 }
550 } else {
551 pr_warn("No GPE found for gmux\n");
552 gmux_data->gpe = -1;
553 }
554
555 if (vga_switcheroo_register_handler(&gmux_handler)) {
556 ret = -ENODEV;
557 goto err_register_handler;
558 }
559
560 init_completion(&gmux_data->powerchange_done);
561 apple_gmux_data = gmux_data;
562 gmux_enable_interrupts(gmux_data);
563
564 return 0;
565
566err_register_handler:
567 if (gmux_data->gpe >= 0)
568 acpi_disable_gpe(NULL, gmux_data->gpe);
569err_enable_gpe:
570 if (gmux_data->gpe >= 0)
571 acpi_remove_notify_handler(gmux_data->dhandle,
572 ACPI_DEVICE_NOTIFY,
573 &gmux_notify_handler);
574err_notify:
575 backlight_device_unregister(bdev);
576err_release:
577 release_region(gmux_data->iostart, gmux_data->iolen);
578err_free:
579 kfree(gmux_data);
580 return ret;
581}
582
583static void gmux_remove(struct pnp_dev *pnp)
584{
585 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
586
587 vga_switcheroo_unregister_handler();
588 gmux_disable_interrupts(gmux_data);
589 if (gmux_data->gpe >= 0) {
590 acpi_disable_gpe(NULL, gmux_data->gpe);
591 acpi_remove_notify_handler(gmux_data->dhandle,
592 ACPI_DEVICE_NOTIFY,
593 &gmux_notify_handler);
594 }
595
596 backlight_device_unregister(gmux_data->bdev);
597
598 release_region(gmux_data->iostart, gmux_data->iolen);
599 apple_gmux_data = NULL;
600 kfree(gmux_data);
601
602 acpi_video_dmi_demote_vendor();
603 acpi_video_register();
604 apple_bl_register();
605}
606
607static const struct pnp_device_id gmux_device_ids[] = {
608 {"APP000B", 0},
609 {"", 0}
610};
611
612static const struct dev_pm_ops gmux_dev_pm_ops = {
613 .suspend = gmux_suspend,
614 .resume = gmux_resume,
615};
616
617static struct pnp_driver gmux_pnp_driver = {
618 .name = "apple-gmux",
619 .probe = gmux_probe,
620 .remove = gmux_remove,
621 .id_table = gmux_device_ids,
622 .driver = {
623 .pm = &gmux_dev_pm_ops,
624 },
625};
626
627static int __init apple_gmux_init(void)
628{
629 return pnp_register_driver(&gmux_pnp_driver);
630}
631
632static void __exit apple_gmux_exit(void)
633{
634 pnp_unregister_driver(&gmux_pnp_driver);
635}
636
637module_init(apple_gmux_init);
638module_exit(apple_gmux_exit);
639
640MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
641MODULE_DESCRIPTION("Apple Gmux Driver");
642MODULE_LICENSE("GPL");
643MODULE_DEVICE_TABLE(pnp, gmux_device_ids);