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 <acpi/video.h> 25 #include <asm/io.h> 26 27 /** 28 * DOC: Overview 29 * 30 * gmux is a microcontroller built into the MacBook Pro to support dual GPUs: 31 * A `Lattice XP2`_ on pre-retinas, a `Renesas R4F2113`_ on retinas. 32 * 33 * (The MacPro6,1 2013 also has a gmux, however it is unclear why since it has 34 * dual GPUs but no built-in display.) 35 * 36 * gmux is connected to the LPC bus of the southbridge. Its I/O ports are 37 * accessed differently depending on the microcontroller: Driver functions 38 * to access a pre-retina gmux are infixed ``_pio_``, those for a retina gmux 39 * are infixed ``_index_``. 40 * 41 * .. _Lattice XP2: 42 * http://www.latticesemi.com/en/Products/FPGAandCPLD/LatticeXP2.aspx 43 * .. _Renesas R4F2113: 44 * http://www.renesas.com/products/mpumcu/h8s/h8s2100/h8s2113/index.jsp 45 */ 46 47 struct apple_gmux_data { 48 unsigned long iostart; 49 unsigned long iolen; 50 bool indexed; 51 struct mutex index_lock; 52 53 struct backlight_device *bdev; 54 55 /* switcheroo data */ 56 acpi_handle dhandle; 57 int gpe; 58 bool external_switchable; 59 enum vga_switcheroo_client_id switch_state_display; 60 enum vga_switcheroo_client_id switch_state_ddc; 61 enum vga_switcheroo_client_id switch_state_external; 62 enum vga_switcheroo_state power_state; 63 struct completion powerchange_done; 64 }; 65 66 static struct apple_gmux_data *apple_gmux_data; 67 68 /* 69 * gmux port offsets. Many of these are not yet used, but may be in the 70 * future, and it's useful to have them documented here anyhow. 71 */ 72 #define GMUX_PORT_VERSION_MAJOR 0x04 73 #define GMUX_PORT_VERSION_MINOR 0x05 74 #define GMUX_PORT_VERSION_RELEASE 0x06 75 #define GMUX_PORT_SWITCH_DISPLAY 0x10 76 #define GMUX_PORT_SWITCH_GET_DISPLAY 0x11 77 #define GMUX_PORT_INTERRUPT_ENABLE 0x14 78 #define GMUX_PORT_INTERRUPT_STATUS 0x16 79 #define GMUX_PORT_SWITCH_DDC 0x28 80 #define GMUX_PORT_SWITCH_EXTERNAL 0x40 81 #define GMUX_PORT_SWITCH_GET_EXTERNAL 0x41 82 #define GMUX_PORT_DISCRETE_POWER 0x50 83 #define GMUX_PORT_MAX_BRIGHTNESS 0x70 84 #define GMUX_PORT_BRIGHTNESS 0x74 85 #define GMUX_PORT_VALUE 0xc2 86 #define GMUX_PORT_READ 0xd0 87 #define GMUX_PORT_WRITE 0xd4 88 89 #define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4) 90 91 #define GMUX_INTERRUPT_ENABLE 0xff 92 #define GMUX_INTERRUPT_DISABLE 0x00 93 94 #define GMUX_INTERRUPT_STATUS_ACTIVE 0 95 #define GMUX_INTERRUPT_STATUS_DISPLAY (1 << 0) 96 #define GMUX_INTERRUPT_STATUS_POWER (1 << 2) 97 #define GMUX_INTERRUPT_STATUS_HOTPLUG (1 << 3) 98 99 #define GMUX_BRIGHTNESS_MASK 0x00ffffff 100 #define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK 101 102 static u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port) 103 { 104 return inb(gmux_data->iostart + port); 105 } 106 107 static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port, 108 u8 val) 109 { 110 outb(val, gmux_data->iostart + port); 111 } 112 113 static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port) 114 { 115 return inl(gmux_data->iostart + port); 116 } 117 118 static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port, 119 u32 val) 120 { 121 int i; 122 u8 tmpval; 123 124 for (i = 0; i < 4; i++) { 125 tmpval = (val >> (i * 8)) & 0xff; 126 outb(tmpval, gmux_data->iostart + port + i); 127 } 128 } 129 130 static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data) 131 { 132 int i = 200; 133 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); 134 135 while (i && (gwr & 0x01)) { 136 inb(gmux_data->iostart + GMUX_PORT_READ); 137 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); 138 udelay(100); 139 i--; 140 } 141 142 return !!i; 143 } 144 145 static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data) 146 { 147 int i = 200; 148 u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); 149 150 while (i && !(gwr & 0x01)) { 151 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); 152 udelay(100); 153 i--; 154 } 155 156 if (gwr & 0x01) 157 inb(gmux_data->iostart + GMUX_PORT_READ); 158 159 return !!i; 160 } 161 162 static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port) 163 { 164 u8 val; 165 166 mutex_lock(&gmux_data->index_lock); 167 gmux_index_wait_ready(gmux_data); 168 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); 169 gmux_index_wait_complete(gmux_data); 170 val = inb(gmux_data->iostart + GMUX_PORT_VALUE); 171 mutex_unlock(&gmux_data->index_lock); 172 173 return val; 174 } 175 176 static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port, 177 u8 val) 178 { 179 mutex_lock(&gmux_data->index_lock); 180 outb(val, gmux_data->iostart + GMUX_PORT_VALUE); 181 gmux_index_wait_ready(gmux_data); 182 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); 183 gmux_index_wait_complete(gmux_data); 184 mutex_unlock(&gmux_data->index_lock); 185 } 186 187 static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port) 188 { 189 u32 val; 190 191 mutex_lock(&gmux_data->index_lock); 192 gmux_index_wait_ready(gmux_data); 193 outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); 194 gmux_index_wait_complete(gmux_data); 195 val = inl(gmux_data->iostart + GMUX_PORT_VALUE); 196 mutex_unlock(&gmux_data->index_lock); 197 198 return val; 199 } 200 201 static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, 202 u32 val) 203 { 204 int i; 205 u8 tmpval; 206 207 mutex_lock(&gmux_data->index_lock); 208 209 for (i = 0; i < 4; i++) { 210 tmpval = (val >> (i * 8)) & 0xff; 211 outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i); 212 } 213 214 gmux_index_wait_ready(gmux_data); 215 outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); 216 gmux_index_wait_complete(gmux_data); 217 mutex_unlock(&gmux_data->index_lock); 218 } 219 220 static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port) 221 { 222 if (gmux_data->indexed) 223 return gmux_index_read8(gmux_data, port); 224 else 225 return gmux_pio_read8(gmux_data, port); 226 } 227 228 static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val) 229 { 230 if (gmux_data->indexed) 231 gmux_index_write8(gmux_data, port, val); 232 else 233 gmux_pio_write8(gmux_data, port, val); 234 } 235 236 static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port) 237 { 238 if (gmux_data->indexed) 239 return gmux_index_read32(gmux_data, port); 240 else 241 return gmux_pio_read32(gmux_data, port); 242 } 243 244 static void gmux_write32(struct apple_gmux_data *gmux_data, int port, 245 u32 val) 246 { 247 if (gmux_data->indexed) 248 gmux_index_write32(gmux_data, port, val); 249 else 250 gmux_pio_write32(gmux_data, port, val); 251 } 252 253 static bool gmux_is_indexed(struct apple_gmux_data *gmux_data) 254 { 255 u16 val; 256 257 outb(0xaa, gmux_data->iostart + 0xcc); 258 outb(0x55, gmux_data->iostart + 0xcd); 259 outb(0x00, gmux_data->iostart + 0xce); 260 261 val = inb(gmux_data->iostart + 0xcc) | 262 (inb(gmux_data->iostart + 0xcd) << 8); 263 264 if (val == 0x55aa) 265 return true; 266 267 return false; 268 } 269 270 /** 271 * DOC: Backlight control 272 * 273 * On single GPU MacBooks, the PWM signal for the backlight is generated by 274 * the GPU. On dual GPU MacBook Pros by contrast, either GPU may be suspended 275 * to conserve energy. Hence the PWM signal needs to be generated by a separate 276 * backlight driver which is controlled by gmux. The earliest generation 277 * MBP5 2008/09 uses a `TI LP8543`_ backlight driver. All newer models 278 * use a `TI LP8545`_. 279 * 280 * .. _TI LP8543: https://www.ti.com/lit/ds/symlink/lp8543.pdf 281 * .. _TI LP8545: https://www.ti.com/lit/ds/symlink/lp8545.pdf 282 */ 283 284 static int gmux_get_brightness(struct backlight_device *bd) 285 { 286 struct apple_gmux_data *gmux_data = bl_get_data(bd); 287 return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) & 288 GMUX_BRIGHTNESS_MASK; 289 } 290 291 static int gmux_update_status(struct backlight_device *bd) 292 { 293 struct apple_gmux_data *gmux_data = bl_get_data(bd); 294 u32 brightness = bd->props.brightness; 295 296 if (bd->props.state & BL_CORE_SUSPENDED) 297 return 0; 298 299 gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness); 300 301 return 0; 302 } 303 304 static const struct backlight_ops gmux_bl_ops = { 305 .options = BL_CORE_SUSPENDRESUME, 306 .get_brightness = gmux_get_brightness, 307 .update_status = gmux_update_status, 308 }; 309 310 /** 311 * DOC: Graphics mux 312 * 313 * On pre-retinas, the LVDS outputs of both GPUs feed into gmux which muxes 314 * either of them to the panel. One of the tricks gmux has up its sleeve is 315 * to lengthen the blanking interval of its output during a switch to 316 * synchronize it with the GPU switched to. This allows for a flicker-free 317 * switch that is imperceptible by the user (`US 8,687,007 B2`_). 318 * 319 * On retinas, muxing is no longer done by gmux itself, but by a separate 320 * chip which is controlled by gmux. The chip is triple sourced, it is 321 * either an `NXP CBTL06142`_, `TI HD3SS212`_ or `Pericom PI3VDP12412`_. 322 * The panel is driven with eDP instead of LVDS since the pixel clock 323 * required for retina resolution exceeds LVDS' limits. 324 * 325 * Pre-retinas are able to switch the panel's DDC pins separately. 326 * This is handled by a `TI SN74LV4066A`_ which is controlled by gmux. 327 * The inactive GPU can thus probe the panel's EDID without switching over 328 * the entire panel. Retinas lack this functionality as the chips used for 329 * eDP muxing are incapable of switching the AUX channel separately (see 330 * the linked data sheets, Pericom would be capable but this is unused). 331 * However the retina panel has the NO_AUX_HANDSHAKE_LINK_TRAINING bit set 332 * in its DPCD, allowing the inactive GPU to skip the AUX handshake and 333 * set up the output with link parameters pre-calibrated by the active GPU. 334 * 335 * The external DP port is only fully switchable on the first two unibody 336 * MacBook Pro generations, MBP5 2008/09 and MBP6 2010. This is done by an 337 * `NXP CBTL06141`_ which is controlled by gmux. It's the predecessor of the 338 * eDP mux on retinas, the difference being support for 2.7 versus 5.4 Gbit/s. 339 * 340 * The following MacBook Pro generations replaced the external DP port with a 341 * combined DP/Thunderbolt port and lost the ability to switch it between GPUs, 342 * connecting it either to the discrete GPU or the Thunderbolt controller. 343 * Oddly enough, while the full port is no longer switchable, AUX and HPD 344 * are still switchable by way of an `NXP CBTL03062`_ (on pre-retinas 345 * MBP8 2011 and MBP9 2012) or two `TI TS3DS10224`_ (on retinas) under the 346 * control of gmux. Since the integrated GPU is missing the main link, 347 * external displays appear to it as phantoms which fail to link-train. 348 * 349 * gmux receives the HPD signal of all display connectors and sends an 350 * interrupt on hotplug. On generations which cannot switch external ports, 351 * the discrete GPU can then be woken to drive the newly connected display. 352 * The ability to switch AUX on these generations could be used to improve 353 * reliability of hotplug detection by having the integrated GPU poll the 354 * ports while the discrete GPU is asleep, but currently we do not make use 355 * of this feature. 356 * 357 * Our switching policy for the external port is that on those generations 358 * which are able to switch it fully, the port is switched together with the 359 * panel when IGD / DIS commands are issued to vga_switcheroo. It is thus 360 * possible to drive e.g. a beamer on battery power with the integrated GPU. 361 * The user may manually switch to the discrete GPU if more performance is 362 * needed. 363 * 364 * On all newer generations, the external port can only be driven by the 365 * discrete GPU. If a display is plugged in while the panel is switched to 366 * the integrated GPU, *both* GPUs will be in use for maximum performance. 367 * To decrease power consumption, the user may manually switch to the 368 * discrete GPU, thereby suspending the integrated GPU. 369 * 370 * gmux' initial switch state on bootup is user configurable via the EFI 371 * variable ``gpu-power-prefs-fa4ce28d-b62f-4c99-9cc3-6815686e30f9`` (5th byte, 372 * 1 = IGD, 0 = DIS). Based on this setting, the EFI firmware tells gmux to 373 * switch the panel and the external DP connector and allocates a framebuffer 374 * for the selected GPU. 375 * 376 * .. _US 8,687,007 B2: https://pimg-fpiw.uspto.gov/fdd/07/870/086/0.pdf 377 * .. _NXP CBTL06141: https://www.nxp.com/documents/data_sheet/CBTL06141.pdf 378 * .. _NXP CBTL06142: https://www.nxp.com/documents/data_sheet/CBTL06141.pdf 379 * .. _TI HD3SS212: https://www.ti.com/lit/ds/symlink/hd3ss212.pdf 380 * .. _Pericom PI3VDP12412: https://www.pericom.com/assets/Datasheets/PI3VDP12412.pdf 381 * .. _TI SN74LV4066A: https://www.ti.com/lit/ds/symlink/sn74lv4066a.pdf 382 * .. _NXP CBTL03062: http://pdf.datasheetarchive.com/indexerfiles/Datasheets-SW16/DSASW00308511.pdf 383 * .. _TI TS3DS10224: https://www.ti.com/lit/ds/symlink/ts3ds10224.pdf 384 */ 385 386 static void gmux_read_switch_state(struct apple_gmux_data *gmux_data) 387 { 388 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DDC) == 1) 389 gmux_data->switch_state_ddc = VGA_SWITCHEROO_IGD; 390 else 391 gmux_data->switch_state_ddc = VGA_SWITCHEROO_DIS; 392 393 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_DISPLAY) == 2) 394 gmux_data->switch_state_display = VGA_SWITCHEROO_IGD; 395 else 396 gmux_data->switch_state_display = VGA_SWITCHEROO_DIS; 397 398 if (gmux_read8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL) == 2) 399 gmux_data->switch_state_external = VGA_SWITCHEROO_IGD; 400 else 401 gmux_data->switch_state_external = VGA_SWITCHEROO_DIS; 402 } 403 404 static void gmux_write_switch_state(struct apple_gmux_data *gmux_data) 405 { 406 if (gmux_data->switch_state_ddc == VGA_SWITCHEROO_IGD) 407 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DDC, 1); 408 else 409 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DDC, 2); 410 411 if (gmux_data->switch_state_display == VGA_SWITCHEROO_IGD) 412 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DISPLAY, 2); 413 else 414 gmux_write8(gmux_data, GMUX_PORT_SWITCH_DISPLAY, 3); 415 416 if (gmux_data->switch_state_external == VGA_SWITCHEROO_IGD) 417 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 2); 418 else 419 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3); 420 } 421 422 static int gmux_switchto(enum vga_switcheroo_client_id id) 423 { 424 apple_gmux_data->switch_state_ddc = id; 425 apple_gmux_data->switch_state_display = id; 426 if (apple_gmux_data->external_switchable) 427 apple_gmux_data->switch_state_external = id; 428 429 gmux_write_switch_state(apple_gmux_data); 430 431 return 0; 432 } 433 434 static int gmux_switch_ddc(enum vga_switcheroo_client_id id) 435 { 436 enum vga_switcheroo_client_id old_ddc_owner = 437 apple_gmux_data->switch_state_ddc; 438 439 if (id == old_ddc_owner) 440 return id; 441 442 pr_debug("Switching DDC from %d to %d\n", old_ddc_owner, id); 443 apple_gmux_data->switch_state_ddc = id; 444 445 if (id == VGA_SWITCHEROO_IGD) 446 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 1); 447 else 448 gmux_write8(apple_gmux_data, GMUX_PORT_SWITCH_DDC, 2); 449 450 return old_ddc_owner; 451 } 452 453 /** 454 * DOC: Power control 455 * 456 * gmux is able to cut power to the discrete GPU. It automatically takes care 457 * of the correct sequence to tear down and bring up the power rails for 458 * core voltage, VRAM and PCIe. 459 */ 460 461 static int gmux_set_discrete_state(struct apple_gmux_data *gmux_data, 462 enum vga_switcheroo_state state) 463 { 464 reinit_completion(&gmux_data->powerchange_done); 465 466 if (state == VGA_SWITCHEROO_ON) { 467 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1); 468 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 3); 469 pr_debug("Discrete card powered up\n"); 470 } else { 471 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 1); 472 gmux_write8(gmux_data, GMUX_PORT_DISCRETE_POWER, 0); 473 pr_debug("Discrete card powered down\n"); 474 } 475 476 gmux_data->power_state = state; 477 478 if (gmux_data->gpe >= 0 && 479 !wait_for_completion_interruptible_timeout(&gmux_data->powerchange_done, 480 msecs_to_jiffies(200))) 481 pr_warn("Timeout waiting for gmux switch to complete\n"); 482 483 return 0; 484 } 485 486 static int gmux_set_power_state(enum vga_switcheroo_client_id id, 487 enum vga_switcheroo_state state) 488 { 489 if (id == VGA_SWITCHEROO_IGD) 490 return 0; 491 492 return gmux_set_discrete_state(apple_gmux_data, state); 493 } 494 495 static enum vga_switcheroo_client_id gmux_get_client_id(struct pci_dev *pdev) 496 { 497 /* 498 * Early Macbook Pros with switchable graphics use nvidia 499 * integrated graphics. Hardcode that the 9400M is integrated. 500 */ 501 if (pdev->vendor == PCI_VENDOR_ID_INTEL) 502 return VGA_SWITCHEROO_IGD; 503 else if (pdev->vendor == PCI_VENDOR_ID_NVIDIA && 504 pdev->device == 0x0863) 505 return VGA_SWITCHEROO_IGD; 506 else 507 return VGA_SWITCHEROO_DIS; 508 } 509 510 static const struct vga_switcheroo_handler gmux_handler_indexed = { 511 .switchto = gmux_switchto, 512 .power_state = gmux_set_power_state, 513 .get_client_id = gmux_get_client_id, 514 }; 515 516 static const struct vga_switcheroo_handler gmux_handler_classic = { 517 .switchto = gmux_switchto, 518 .switch_ddc = gmux_switch_ddc, 519 .power_state = gmux_set_power_state, 520 .get_client_id = gmux_get_client_id, 521 }; 522 523 /** 524 * DOC: Interrupt 525 * 526 * gmux is also connected to a GPIO pin of the southbridge and thereby is able 527 * to trigger an ACPI GPE. On the MBP5 2008/09 it's GPIO pin 22 of the Nvidia 528 * MCP79, on all following generations it's GPIO pin 6 of the Intel PCH. 529 * The GPE merely signals that an interrupt occurred, the actual type of event 530 * is identified by reading a gmux register. 531 */ 532 533 static inline void gmux_disable_interrupts(struct apple_gmux_data *gmux_data) 534 { 535 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE, 536 GMUX_INTERRUPT_DISABLE); 537 } 538 539 static inline void gmux_enable_interrupts(struct apple_gmux_data *gmux_data) 540 { 541 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_ENABLE, 542 GMUX_INTERRUPT_ENABLE); 543 } 544 545 static inline u8 gmux_interrupt_get_status(struct apple_gmux_data *gmux_data) 546 { 547 return gmux_read8(gmux_data, GMUX_PORT_INTERRUPT_STATUS); 548 } 549 550 static void gmux_clear_interrupts(struct apple_gmux_data *gmux_data) 551 { 552 u8 status; 553 554 /* to clear interrupts write back current status */ 555 status = gmux_interrupt_get_status(gmux_data); 556 gmux_write8(gmux_data, GMUX_PORT_INTERRUPT_STATUS, status); 557 } 558 559 static void gmux_notify_handler(acpi_handle device, u32 value, void *context) 560 { 561 u8 status; 562 struct pnp_dev *pnp = (struct pnp_dev *)context; 563 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp); 564 565 status = gmux_interrupt_get_status(gmux_data); 566 gmux_disable_interrupts(gmux_data); 567 pr_debug("Notify handler called: status %d\n", status); 568 569 gmux_clear_interrupts(gmux_data); 570 gmux_enable_interrupts(gmux_data); 571 572 if (status & GMUX_INTERRUPT_STATUS_POWER) 573 complete(&gmux_data->powerchange_done); 574 } 575 576 static int gmux_suspend(struct device *dev) 577 { 578 struct pnp_dev *pnp = to_pnp_dev(dev); 579 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp); 580 581 gmux_disable_interrupts(gmux_data); 582 return 0; 583 } 584 585 static int gmux_resume(struct device *dev) 586 { 587 struct pnp_dev *pnp = to_pnp_dev(dev); 588 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp); 589 590 gmux_enable_interrupts(gmux_data); 591 gmux_write_switch_state(gmux_data); 592 if (gmux_data->power_state == VGA_SWITCHEROO_OFF) 593 gmux_set_discrete_state(gmux_data, gmux_data->power_state); 594 return 0; 595 } 596 597 static int is_thunderbolt(struct device *dev, void *data) 598 { 599 return to_pci_dev(dev)->is_thunderbolt; 600 } 601 602 static int gmux_probe(struct pnp_dev *pnp, const struct pnp_device_id *id) 603 { 604 struct apple_gmux_data *gmux_data; 605 struct resource *res; 606 struct backlight_properties props; 607 struct backlight_device *bdev; 608 u8 ver_major, ver_minor, ver_release; 609 int ret = -ENXIO; 610 acpi_status status; 611 unsigned long long gpe; 612 613 if (apple_gmux_data) 614 return -EBUSY; 615 616 gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL); 617 if (!gmux_data) 618 return -ENOMEM; 619 pnp_set_drvdata(pnp, gmux_data); 620 621 res = pnp_get_resource(pnp, IORESOURCE_IO, 0); 622 if (!res) { 623 pr_err("Failed to find gmux I/O resource\n"); 624 goto err_free; 625 } 626 627 gmux_data->iostart = res->start; 628 gmux_data->iolen = resource_size(res); 629 630 if (gmux_data->iolen < GMUX_MIN_IO_LEN) { 631 pr_err("gmux I/O region too small (%lu < %u)\n", 632 gmux_data->iolen, GMUX_MIN_IO_LEN); 633 goto err_free; 634 } 635 636 if (!request_region(gmux_data->iostart, gmux_data->iolen, 637 "Apple gmux")) { 638 pr_err("gmux I/O already in use\n"); 639 goto err_free; 640 } 641 642 /* 643 * Invalid version information may indicate either that the gmux 644 * device isn't present or that it's a new one that uses indexed 645 * io 646 */ 647 648 ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR); 649 ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR); 650 ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE); 651 if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) { 652 if (gmux_is_indexed(gmux_data)) { 653 u32 version; 654 mutex_init(&gmux_data->index_lock); 655 gmux_data->indexed = true; 656 version = gmux_read32(gmux_data, 657 GMUX_PORT_VERSION_MAJOR); 658 ver_major = (version >> 24) & 0xff; 659 ver_minor = (version >> 16) & 0xff; 660 ver_release = (version >> 8) & 0xff; 661 } else { 662 pr_info("gmux device not present\n"); 663 ret = -ENODEV; 664 goto err_release; 665 } 666 } 667 pr_info("Found gmux version %d.%d.%d [%s]\n", ver_major, ver_minor, 668 ver_release, (gmux_data->indexed ? "indexed" : "classic")); 669 670 memset(&props, 0, sizeof(props)); 671 props.type = BACKLIGHT_PLATFORM; 672 props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS); 673 674 /* 675 * Currently it's assumed that the maximum brightness is less than 676 * 2^24 for compatibility with old gmux versions. Cap the max 677 * brightness at this value, but print a warning if the hardware 678 * reports something higher so that it can be fixed. 679 */ 680 if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS)) 681 props.max_brightness = GMUX_MAX_BRIGHTNESS; 682 683 bdev = backlight_device_register("gmux_backlight", &pnp->dev, 684 gmux_data, &gmux_bl_ops, &props); 685 if (IS_ERR(bdev)) { 686 ret = PTR_ERR(bdev); 687 goto err_release; 688 } 689 690 gmux_data->bdev = bdev; 691 bdev->props.brightness = gmux_get_brightness(bdev); 692 backlight_update_status(bdev); 693 694 /* 695 * The backlight situation on Macs is complicated. If the gmux is 696 * present it's the best choice, because it always works for 697 * backlight control and supports more levels than other options. 698 * Disable the other backlight choices. 699 */ 700 acpi_video_set_dmi_backlight_type(acpi_backlight_vendor); 701 apple_bl_unregister(); 702 703 gmux_data->power_state = VGA_SWITCHEROO_ON; 704 705 gmux_data->dhandle = ACPI_HANDLE(&pnp->dev); 706 if (!gmux_data->dhandle) { 707 pr_err("Cannot find acpi handle for pnp device %s\n", 708 dev_name(&pnp->dev)); 709 ret = -ENODEV; 710 goto err_notify; 711 } 712 713 status = acpi_evaluate_integer(gmux_data->dhandle, "GMGP", NULL, &gpe); 714 if (ACPI_SUCCESS(status)) { 715 gmux_data->gpe = (int)gpe; 716 717 status = acpi_install_notify_handler(gmux_data->dhandle, 718 ACPI_DEVICE_NOTIFY, 719 &gmux_notify_handler, pnp); 720 if (ACPI_FAILURE(status)) { 721 pr_err("Install notify handler failed: %s\n", 722 acpi_format_exception(status)); 723 ret = -ENODEV; 724 goto err_notify; 725 } 726 727 status = acpi_enable_gpe(NULL, gmux_data->gpe); 728 if (ACPI_FAILURE(status)) { 729 pr_err("Cannot enable gpe: %s\n", 730 acpi_format_exception(status)); 731 goto err_enable_gpe; 732 } 733 } else { 734 pr_warn("No GPE found for gmux\n"); 735 gmux_data->gpe = -1; 736 } 737 738 /* 739 * If Thunderbolt is present, the external DP port is not fully 740 * switchable. Force its AUX channel to the discrete GPU. 741 */ 742 gmux_data->external_switchable = 743 !bus_for_each_dev(&pci_bus_type, NULL, NULL, is_thunderbolt); 744 if (!gmux_data->external_switchable) 745 gmux_write8(gmux_data, GMUX_PORT_SWITCH_EXTERNAL, 3); 746 747 apple_gmux_data = gmux_data; 748 init_completion(&gmux_data->powerchange_done); 749 gmux_enable_interrupts(gmux_data); 750 gmux_read_switch_state(gmux_data); 751 752 /* 753 * Retina MacBook Pros cannot switch the panel's AUX separately 754 * and need eDP pre-calibration. They are distinguishable from 755 * pre-retinas by having an "indexed" gmux. 756 * 757 * Pre-retina MacBook Pros can switch the panel's DDC separately. 758 */ 759 if (gmux_data->indexed) 760 ret = vga_switcheroo_register_handler(&gmux_handler_indexed, 761 VGA_SWITCHEROO_NEEDS_EDP_CONFIG); 762 else 763 ret = vga_switcheroo_register_handler(&gmux_handler_classic, 764 VGA_SWITCHEROO_CAN_SWITCH_DDC); 765 if (ret) { 766 pr_err("Failed to register vga_switcheroo handler\n"); 767 goto err_register_handler; 768 } 769 770 return 0; 771 772 err_register_handler: 773 gmux_disable_interrupts(gmux_data); 774 apple_gmux_data = NULL; 775 if (gmux_data->gpe >= 0) 776 acpi_disable_gpe(NULL, gmux_data->gpe); 777 err_enable_gpe: 778 if (gmux_data->gpe >= 0) 779 acpi_remove_notify_handler(gmux_data->dhandle, 780 ACPI_DEVICE_NOTIFY, 781 &gmux_notify_handler); 782 err_notify: 783 backlight_device_unregister(bdev); 784 err_release: 785 release_region(gmux_data->iostart, gmux_data->iolen); 786 err_free: 787 kfree(gmux_data); 788 return ret; 789 } 790 791 static void gmux_remove(struct pnp_dev *pnp) 792 { 793 struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp); 794 795 vga_switcheroo_unregister_handler(); 796 gmux_disable_interrupts(gmux_data); 797 if (gmux_data->gpe >= 0) { 798 acpi_disable_gpe(NULL, gmux_data->gpe); 799 acpi_remove_notify_handler(gmux_data->dhandle, 800 ACPI_DEVICE_NOTIFY, 801 &gmux_notify_handler); 802 } 803 804 backlight_device_unregister(gmux_data->bdev); 805 806 release_region(gmux_data->iostart, gmux_data->iolen); 807 apple_gmux_data = NULL; 808 kfree(gmux_data); 809 810 acpi_video_register(); 811 apple_bl_register(); 812 } 813 814 static const struct pnp_device_id gmux_device_ids[] = { 815 {GMUX_ACPI_HID, 0}, 816 {"", 0} 817 }; 818 819 static const struct dev_pm_ops gmux_dev_pm_ops = { 820 .suspend = gmux_suspend, 821 .resume = gmux_resume, 822 }; 823 824 static struct pnp_driver gmux_pnp_driver = { 825 .name = "apple-gmux", 826 .probe = gmux_probe, 827 .remove = gmux_remove, 828 .id_table = gmux_device_ids, 829 .driver = { 830 .pm = &gmux_dev_pm_ops, 831 }, 832 }; 833 834 module_pnp_driver(gmux_pnp_driver); 835 MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>"); 836 MODULE_DESCRIPTION("Apple Gmux Driver"); 837 MODULE_LICENSE("GPL"); 838 MODULE_DEVICE_TABLE(pnp, gmux_device_ids); 839