xref: /NextBSD/sys/dev/drm2/i915/intel_iic.c (revision 4557fabb34e865d7f40be64b39c9e34fa41dbb60)
1 /*
2  * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
3  * Copyright © 2006-2008,2010 Intel Corporation
4  *   Jesse Barnes <jesse.barnes@intel.com>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23  * DEALINGS IN THE SOFTWARE.
24  *
25  * Authors:
26  *	Eric Anholt <eric@anholt.net>
27  *	Chris Wilson <chris@chris-wilson.co.uk>
28  *
29  * Copyright (c) 2011 The FreeBSD Foundation
30  * All rights reserved.
31  *
32  * This software was developed by Konstantin Belousov under sponsorship from
33  * the FreeBSD Foundation.
34  *
35  * Redistribution and use in source and binary forms, with or without
36  * modification, are permitted provided that the following conditions
37  * are met:
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  *
44  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
47  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
54  * SUCH DAMAGE.
55  */
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
58 
59 #include <dev/drm2/drmP.h>
60 #include <dev/drm2/drm.h>
61 #include <dev/drm2/i915/i915_drm.h>
62 #include <dev/drm2/i915/i915_drv.h>
63 #include <dev/drm2/i915/intel_drv.h>
64 #include <dev/iicbus/iic.h>
65 #include <dev/iicbus/iiconf.h>
66 #include <dev/iicbus/iicbus.h>
67 #include "iicbus_if.h"
68 #include "iicbb_if.h"
69 
70 static void intel_teardown_gmbus_m(struct drm_device *dev, int m);
71 
72 struct gmbus_port {
73 	const char *name;
74 	int reg;
75 };
76 
77 static const struct gmbus_port gmbus_ports[] = {
78 	{ "ssc", GPIOB },
79 	{ "vga", GPIOA },
80 	{ "panel", GPIOC },
81 	{ "dpc", GPIOD },
82 	{ "dpb", GPIOE },
83 	{ "dpd", GPIOF },
84 };
85 
86 /* Intel GPIO access functions */
87 
88 #define I2C_RISEFALL_TIME 10
89 
90 struct intel_iic_softc {
91 	struct drm_device *drm_dev;
92 	device_t iic_dev;
93 	bool force_bit_dev;
94 	char name[32];
95 	uint32_t reg;
96 	uint32_t reg0;
97 };
98 
99 void
intel_iic_reset(struct drm_device * dev)100 intel_iic_reset(struct drm_device *dev)
101 {
102 	struct drm_i915_private *dev_priv = dev->dev_private;
103 	I915_WRITE(dev_priv->gpio_mmio_base + GMBUS0, 0);
104 }
105 
106 static int
intel_iicbus_reset(device_t idev,u_char speed,u_char addr,u_char * oldaddr)107 intel_iicbus_reset(device_t idev, u_char speed, u_char addr, u_char *oldaddr)
108 {
109 	struct intel_iic_softc *sc;
110 	struct drm_device *dev;
111 
112 	sc = device_get_softc(idev);
113 	dev = sc->drm_dev;
114 
115 	intel_iic_reset(dev);
116 	return (0);
117 }
118 
intel_i2c_quirk_set(struct drm_i915_private * dev_priv,bool enable)119 static void intel_i2c_quirk_set(struct drm_i915_private *dev_priv, bool enable)
120 {
121 	u32 val;
122 
123 	/* When using bit bashing for I2C, this bit needs to be set to 1 */
124 	if (!IS_PINEVIEW(dev_priv->dev))
125 		return;
126 
127 	val = I915_READ(DSPCLK_GATE_D);
128 	if (enable)
129 		val |= DPCUNIT_CLOCK_GATE_DISABLE;
130 	else
131 		val &= ~DPCUNIT_CLOCK_GATE_DISABLE;
132 	I915_WRITE(DSPCLK_GATE_D, val);
133 }
134 
get_reserved(device_t idev)135 static u32 get_reserved(device_t idev)
136 {
137 	struct intel_iic_softc *sc = device_get_softc(idev);
138 	struct drm_device *dev = sc->drm_dev;
139 	struct drm_i915_private *dev_priv = dev->dev_private;
140 	u32 reserved = 0;
141 
142 	if (!IS_I830(dev) && !IS_845G(dev))
143 		reserved = I915_READ_NOTRACE(sc->reg) &
144 					     (GPIO_DATA_PULLUP_DISABLE |
145 					      GPIO_CLOCK_PULLUP_DISABLE);
146 
147 	return reserved;
148 }
149 
get_clock(device_t adapter)150 static int get_clock(device_t adapter)
151 {
152 	struct intel_iic_softc *sc = device_get_softc(adapter);
153 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
154 	u32 reserved = get_reserved(adapter);
155 	I915_WRITE_NOTRACE(sc->reg, reserved | GPIO_CLOCK_DIR_MASK);
156 	I915_WRITE_NOTRACE(sc->reg, reserved);
157 	return ((I915_READ_NOTRACE(sc->reg) & GPIO_CLOCK_VAL_IN) != 0);
158 }
159 
get_data(device_t adapter)160 static int get_data(device_t adapter)
161 {
162 	struct intel_iic_softc *sc = device_get_softc(adapter);
163 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
164 	u32 reserved = get_reserved(adapter);
165 	I915_WRITE_NOTRACE(sc->reg, reserved | GPIO_DATA_DIR_MASK);
166 	I915_WRITE_NOTRACE(sc->reg, reserved);
167 	return ((I915_READ_NOTRACE(sc->reg) & GPIO_DATA_VAL_IN) != 0);
168 }
169 
set_clock(device_t adapter,int state_high)170 static void set_clock(device_t adapter, int state_high)
171 {
172 	struct intel_iic_softc *sc = device_get_softc(adapter);
173 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
174 	u32 reserved = get_reserved(adapter);
175 	u32 clock_bits;
176 
177 	if (state_high)
178 		clock_bits = GPIO_CLOCK_DIR_IN | GPIO_CLOCK_DIR_MASK;
179 	else
180 		clock_bits = GPIO_CLOCK_DIR_OUT | GPIO_CLOCK_DIR_MASK |
181 			GPIO_CLOCK_VAL_MASK;
182 
183 	I915_WRITE_NOTRACE(sc->reg, reserved | clock_bits);
184 	POSTING_READ(sc->reg);
185 }
186 
set_data(device_t adapter,int state_high)187 static void set_data(device_t adapter, int state_high)
188 {
189 	struct intel_iic_softc *sc = device_get_softc(adapter);
190 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
191 	u32 reserved = get_reserved(adapter);
192 	u32 data_bits;
193 
194 	if (state_high)
195 		data_bits = GPIO_DATA_DIR_IN | GPIO_DATA_DIR_MASK;
196 	else
197 		data_bits = GPIO_DATA_DIR_OUT | GPIO_DATA_DIR_MASK |
198 			GPIO_DATA_VAL_MASK;
199 
200 	I915_WRITE_NOTRACE(sc->reg, reserved | data_bits);
201 	POSTING_READ(sc->reg);
202 }
203 
204 static int
intel_gpio_pre_xfer(device_t adapter)205 intel_gpio_pre_xfer(device_t adapter)
206 {
207 	struct intel_iic_softc *sc = device_get_softc(adapter);
208 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
209 
210 	intel_iic_reset(sc->drm_dev);
211 	intel_i2c_quirk_set(dev_priv, true);
212 	IICBB_SETSDA(adapter, 1);
213 	IICBB_SETSCL(adapter, 1);
214 	DELAY(I2C_RISEFALL_TIME);
215 	return 0;
216 }
217 
218 static void
intel_gpio_post_xfer(device_t adapter)219 intel_gpio_post_xfer(device_t adapter)
220 {
221 	struct intel_iic_softc *sc = device_get_softc(adapter);
222 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
223 
224 	IICBB_SETSDA(adapter, 1);
225 	IICBB_SETSCL(adapter, 1);
226 	intel_i2c_quirk_set(dev_priv, false);
227 }
228 
229 static int
gmbus_xfer_read(struct drm_i915_private * dev_priv,struct iic_msg * msg,u32 gmbus1_index)230 gmbus_xfer_read(struct drm_i915_private *dev_priv, struct iic_msg *msg,
231 		u32 gmbus1_index)
232 {
233 	int reg_offset = dev_priv->gpio_mmio_base;
234 	u16 len = msg->len;
235 	u8 *buf = msg->buf;
236 
237 	I915_WRITE(GMBUS1 + reg_offset,
238 		   gmbus1_index |
239 		   GMBUS_CYCLE_WAIT |
240 		   (len << GMBUS_BYTE_COUNT_SHIFT) |
241 		   (msg->slave << (GMBUS_SLAVE_ADDR_SHIFT - 1)) |
242 		   GMBUS_SLAVE_READ | GMBUS_SW_RDY);
243 	while (len) {
244 		int ret;
245 		u32 val, loop = 0;
246 		u32 gmbus2;
247 
248 		ret = _intel_wait_for(sc->drm_dev,
249 			       ((gmbus2 = I915_READ(GMBUS2 + reg_offset)) &
250 			       (GMBUS_SATOER | GMBUS_HW_RDY)),
251 			       50, 1, "915gbr");
252 		if (ret)
253 			return -ETIMEDOUT;
254 		if (gmbus2 & GMBUS_SATOER)
255 			return -ENXIO;
256 
257 		val = I915_READ(GMBUS3 + reg_offset);
258 		do {
259 			*buf++ = val & 0xff;
260 			val >>= 8;
261 		} while (--len && ++loop < 4);
262 	}
263 
264 	return 0;
265 }
266 
267 static int
gmbus_xfer_write(struct drm_i915_private * dev_priv,struct iic_msg * msg)268 gmbus_xfer_write(struct drm_i915_private *dev_priv, struct iic_msg *msg)
269 {
270 	int reg_offset = dev_priv->gpio_mmio_base;
271 	u16 len = msg->len;
272 	u8 *buf = msg->buf;
273 	u32 val, loop;
274 
275 	val = loop = 0;
276 	while (len && loop < 4) {
277 		val |= *buf++ << (8 * loop++);
278 		len -= 1;
279 	}
280 
281 	I915_WRITE(GMBUS3 + reg_offset, val);
282 	I915_WRITE(GMBUS1 + reg_offset,
283 		   GMBUS_CYCLE_WAIT |
284 		   (msg->len << GMBUS_BYTE_COUNT_SHIFT) |
285 		   (msg->slave << (GMBUS_SLAVE_ADDR_SHIFT - 1)) |
286 		   GMBUS_SLAVE_WRITE | GMBUS_SW_RDY);
287 	while (len) {
288 		int ret;
289 		u32 gmbus2;
290 
291 		val = loop = 0;
292 		do {
293 			val |= *buf++ << (8 * loop);
294 		} while (--len && ++loop < 4);
295 
296 		I915_WRITE(GMBUS3 + reg_offset, val);
297 
298 		ret = _intel_wait_for(sc->drm_dev,
299 			       ((gmbus2 = I915_READ(GMBUS2 + reg_offset)) &
300 			       (GMBUS_SATOER | GMBUS_HW_RDY)),
301 			       50, 1, "915gbw");
302 		if (ret)
303 			return -ETIMEDOUT;
304 		if (gmbus2 & GMBUS_SATOER)
305 			return -ENXIO;
306 	}
307 	return 0;
308 }
309 
310 /*
311  * The gmbus controller can combine a 1 or 2 byte write with a read that
312  * immediately follows it by using an "INDEX" cycle.
313  */
314 static bool
gmbus_is_index_read(struct iic_msg * msgs,int i,int num)315 gmbus_is_index_read(struct iic_msg *msgs, int i, int num)
316 {
317 	return (i + 1 < num &&
318 		!(msgs[i].flags & IIC_M_RD) && msgs[i].len <= 2 &&
319 		(msgs[i + 1].flags & IIC_M_RD));
320 }
321 
322 static int
gmbus_xfer_index_read(struct drm_i915_private * dev_priv,struct iic_msg * msgs)323 gmbus_xfer_index_read(struct drm_i915_private *dev_priv, struct iic_msg *msgs)
324 {
325 	int reg_offset = dev_priv->gpio_mmio_base;
326 	u32 gmbus1_index = 0;
327 	u32 gmbus5 = 0;
328 	int ret;
329 
330 	if (msgs[0].len == 2)
331 		gmbus5 = GMBUS_2BYTE_INDEX_EN |
332 			 msgs[0].buf[1] | (msgs[0].buf[0] << 8);
333 	if (msgs[0].len == 1)
334 		gmbus1_index = GMBUS_CYCLE_INDEX |
335 			       (msgs[0].buf[0] << GMBUS_SLAVE_INDEX_SHIFT);
336 
337 	/* GMBUS5 holds 16-bit index */
338 	if (gmbus5)
339 		I915_WRITE(GMBUS5 + reg_offset, gmbus5);
340 
341 	ret = gmbus_xfer_read(dev_priv, &msgs[1], gmbus1_index);
342 
343 	/* Clear GMBUS5 after each index transfer */
344 	if (gmbus5)
345 		I915_WRITE(GMBUS5 + reg_offset, 0);
346 
347 	return ret;
348 }
349 
350 static int
gmbus_xfer(device_t adapter,struct iic_msg * msgs,uint32_t num)351 gmbus_xfer(device_t adapter,
352 	   struct iic_msg *msgs,
353 	   uint32_t num)
354 {
355 	struct intel_iic_softc *sc = device_get_softc(adapter);
356 	struct drm_i915_private *dev_priv = sc->drm_dev->dev_private;
357 	int error, i, ret, reg_offset, unit;
358 
359 	error = 0;
360 	unit = device_get_unit(adapter);
361 
362 	sx_xlock(&dev_priv->gmbus_sx);
363 	if (sc->force_bit_dev) {
364 		error = -IICBUS_TRANSFER(dev_priv->bbbus[unit], msgs, num);
365 		goto out;
366 	}
367 
368 	reg_offset = dev_priv->gpio_mmio_base;
369 
370 	I915_WRITE(GMBUS0 + reg_offset, sc->reg0);
371 
372 	for (i = 0; i < num; i++) {
373 		u32 gmbus2;
374 
375 		if (gmbus_is_index_read(msgs, i, num)) {
376 			error = gmbus_xfer_index_read(dev_priv, &msgs[i]);
377 			i += 1;  /* set i to the index of the read xfer */
378 		} else if (msgs[i].flags & IIC_M_RD) {
379 			error = gmbus_xfer_read(dev_priv, &msgs[i], 0);
380 		} else {
381 			error = gmbus_xfer_write(dev_priv, &msgs[i]);
382 		}
383 
384 		if (error == -ETIMEDOUT)
385 			goto timeout;
386 		if (error == -ENXIO)
387 			goto clear_err;
388 
389 		ret = _intel_wait_for(sc->drm_dev,
390 		    ((gmbus2 = I915_READ(GMBUS2 + reg_offset)) &
391 		    (GMBUS_SATOER | GMBUS_HW_WAIT_PHASE)),
392 		    50, 1, "915gbh");
393 		if (ret)
394 			goto timeout;
395 		if (gmbus2 & GMBUS_SATOER)
396 			goto clear_err;
397 	}
398 
399 	/* Generate a STOP condition on the bus. Note that gmbus can't generata
400 	 * a STOP on the very first cycle. To simplify the code we
401 	 * unconditionally generate the STOP condition with an additional gmbus
402 	 * cycle. */
403 	I915_WRITE(GMBUS1 + reg_offset, GMBUS_CYCLE_STOP | GMBUS_SW_RDY);
404 
405 	/* Mark the GMBUS interface as disabled after waiting for idle.
406 	 * We will re-enable it at the start of the next xfer,
407 	 * till then let it sleep.
408 	 */
409 	if (_intel_wait_for(dev,
410 	    (I915_READ(GMBUS2 + reg_offset) & GMBUS_ACTIVE) == 0,
411 	    10, 1, "915gbu")) {
412 		DRM_DEBUG_KMS("GMBUS [%s] timed out waiting for idle\n",
413 			 sc->name);
414 		error = -ETIMEDOUT;
415 	}
416 	I915_WRITE(GMBUS0 + reg_offset, 0);
417 	goto out;
418 
419 clear_err:
420 	/*
421 	 * Wait for bus to IDLE before clearing NAK.
422 	 * If we clear the NAK while bus is still active, then it will stay
423 	 * active and the next transaction may fail.
424 	 */
425 	if (_intel_wait_for(dev,
426 	    (I915_READ(GMBUS2 + reg_offset) & GMBUS_ACTIVE) == 0,
427 	    10, 1, "915gbu"))
428 		DRM_DEBUG_KMS("GMBUS [%s] timed out after NAK\n", sc->name);
429 
430 	/* Toggle the Software Clear Interrupt bit. This has the effect
431 	 * of resetting the GMBUS controller and so clearing the
432 	 * BUS_ERROR raised by the slave's NAK.
433 	 */
434 	I915_WRITE(GMBUS1 + reg_offset, GMBUS_SW_CLR_INT);
435 	I915_WRITE(GMBUS1 + reg_offset, 0);
436 	I915_WRITE(GMBUS0 + reg_offset, 0);
437 
438 	DRM_DEBUG_KMS("GMBUS [%s] NAK for addr: %04x %c(%d)\n",
439 			 sc->name, msgs[i].slave,
440 			 (msgs[i].flags & IIC_M_RD) ? 'r' : 'w', msgs[i].len);
441 
442 	/*
443 	 * If no ACK is received during the address phase of a transaction,
444 	 * the adapter must report -ENXIO.
445 	 * It is not clear what to return if no ACK is received at other times.
446 	 * So, we always return -ENXIO in all NAK cases, to ensure we send
447 	 * it at least during the one case that is specified.
448 	 */
449 	error = -ENXIO;
450 	goto out;
451 
452 timeout:
453 	DRM_INFO("GMBUS [%s] timed out, falling back to bit banging on pin %d\n",
454 		 sc->name, sc->reg0 & 0xff);
455 	I915_WRITE(GMBUS0 + reg_offset, 0);
456 
457 	/* Hardware may not support GMBUS over these pins? Try GPIO bitbanging instead. */
458 	sc->force_bit_dev = true;
459 	error = -IICBUS_TRANSFER(dev_priv->bbbus[unit], msgs, num);
460 
461 out:
462 	sx_xunlock(&dev_priv->gmbus_sx);
463 	return -error;
464 }
465 
466 static int
intel_gmbus_probe(device_t dev)467 intel_gmbus_probe(device_t dev)
468 {
469 
470 	return (BUS_PROBE_SPECIFIC);
471 }
472 
473 static int
intel_gmbus_attach(device_t idev)474 intel_gmbus_attach(device_t idev)
475 {
476 	struct drm_i915_private *dev_priv;
477 	struct intel_iic_softc *sc;
478 	int pin, port;
479 
480 	sc = device_get_softc(idev);
481 	sc->drm_dev = device_get_softc(device_get_parent(idev));
482 	dev_priv = sc->drm_dev->dev_private;
483 	pin = device_get_unit(idev);
484 	port = pin + 1;
485 
486 	snprintf(sc->name, sizeof(sc->name), "gmbus %s",
487 	    intel_gmbus_is_port_valid(port) ? gmbus_ports[pin].name :
488 	    "reserved");
489 	device_set_desc(idev, sc->name);
490 
491 	/* By default use a conservative clock rate */
492 	sc->reg0 = port | GMBUS_RATE_100KHZ;
493 
494 	/* gmbus seems to be broken on i830 */
495 	if (IS_I830(sc->drm_dev))
496 		sc->force_bit_dev = true;
497 #if 0
498 	if (IS_GEN2(sc->drm_dev)) {
499 		sc->force_bit_dev = true;
500 	}
501 #endif
502 
503 	/* add bus interface device */
504 	sc->iic_dev = device_add_child(idev, "iicbus", -1);
505 	if (sc->iic_dev == NULL)
506 		return (ENXIO);
507 	device_quiet(sc->iic_dev);
508 	bus_generic_attach(idev);
509 
510 	return (0);
511 }
512 
513 static int
intel_gmbus_detach(device_t idev)514 intel_gmbus_detach(device_t idev)
515 {
516 	struct intel_iic_softc *sc;
517 	struct drm_i915_private *dev_priv;
518 	device_t child;
519 	int u;
520 
521 	sc = device_get_softc(idev);
522 	u = device_get_unit(idev);
523 	dev_priv = sc->drm_dev->dev_private;
524 
525 	child = sc->iic_dev;
526 	bus_generic_detach(idev);
527 	if (child != NULL)
528 		device_delete_child(idev, child);
529 
530 	return (0);
531 }
532 
533 static int
intel_iicbb_probe(device_t dev)534 intel_iicbb_probe(device_t dev)
535 {
536 
537 	return (BUS_PROBE_DEFAULT);
538 }
539 
540 static int
intel_iicbb_attach(device_t idev)541 intel_iicbb_attach(device_t idev)
542 {
543 	struct intel_iic_softc *sc;
544 	struct drm_i915_private *dev_priv;
545 	int pin, port;
546 
547 	sc = device_get_softc(idev);
548 	sc->drm_dev = device_get_softc(device_get_parent(idev));
549 	dev_priv = sc->drm_dev->dev_private;
550 	pin = device_get_unit(idev);
551 	port = pin + 1;
552 
553 	snprintf(sc->name, sizeof(sc->name), "i915 iicbb %s",
554 	    intel_gmbus_is_port_valid(port) ? gmbus_ports[pin].name :
555 	    "reserved");
556 	device_set_desc(idev, sc->name);
557 
558 	if (!intel_gmbus_is_port_valid(port))
559 		pin = 1 ; /* GPIOA, VGA */
560 	sc->reg0 = pin | GMBUS_RATE_100KHZ;
561 	sc->reg = dev_priv->gpio_mmio_base + gmbus_ports[pin].reg;
562 
563 	/* add generic bit-banging code */
564 	sc->iic_dev = device_add_child(idev, "iicbb", -1);
565 	if (sc->iic_dev == NULL)
566 		return (ENXIO);
567 	device_quiet(sc->iic_dev);
568 	bus_generic_attach(idev);
569 	iicbus_set_nostop(idev, true);
570 
571 	return (0);
572 }
573 
574 static int
intel_iicbb_detach(device_t idev)575 intel_iicbb_detach(device_t idev)
576 {
577 	struct intel_iic_softc *sc;
578 	device_t child;
579 
580 	sc = device_get_softc(idev);
581 	child = sc->iic_dev;
582 	bus_generic_detach(idev);
583 	if (child)
584 		device_delete_child(idev, child);
585 	return (0);
586 }
587 
588 static device_method_t intel_gmbus_methods[] = {
589 	DEVMETHOD(device_probe,		intel_gmbus_probe),
590 	DEVMETHOD(device_attach,	intel_gmbus_attach),
591 	DEVMETHOD(device_detach,	intel_gmbus_detach),
592 	DEVMETHOD(iicbus_reset,		intel_iicbus_reset),
593 	DEVMETHOD(iicbus_transfer,	gmbus_xfer),
594 	DEVMETHOD_END
595 };
596 static driver_t intel_gmbus_driver = {
597 	"intel_gmbus",
598 	intel_gmbus_methods,
599 	sizeof(struct intel_iic_softc)
600 };
601 static devclass_t intel_gmbus_devclass;
602 DRIVER_MODULE_ORDERED(intel_gmbus, drmn, intel_gmbus_driver,
603     intel_gmbus_devclass, 0, 0, SI_ORDER_FIRST);
604 DRIVER_MODULE(iicbus, intel_gmbus, iicbus_driver, iicbus_devclass, 0, 0);
605 
606 static device_method_t intel_iicbb_methods[] =	{
607 	DEVMETHOD(device_probe,		intel_iicbb_probe),
608 	DEVMETHOD(device_attach,	intel_iicbb_attach),
609 	DEVMETHOD(device_detach,	intel_iicbb_detach),
610 
611 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
612 	DEVMETHOD(bus_print_child,	bus_generic_print_child),
613 
614 	DEVMETHOD(iicbb_callback,	iicbus_null_callback),
615 	DEVMETHOD(iicbb_reset,		intel_iicbus_reset),
616 	DEVMETHOD(iicbb_setsda,		set_data),
617 	DEVMETHOD(iicbb_setscl,		set_clock),
618 	DEVMETHOD(iicbb_getsda,		get_data),
619 	DEVMETHOD(iicbb_getscl,		get_clock),
620 	DEVMETHOD(iicbb_pre_xfer,	intel_gpio_pre_xfer),
621 	DEVMETHOD(iicbb_post_xfer,	intel_gpio_post_xfer),
622 	DEVMETHOD_END
623 };
624 static driver_t intel_iicbb_driver = {
625 	"intel_iicbb",
626 	intel_iicbb_methods,
627 	sizeof(struct intel_iic_softc)
628 };
629 static devclass_t intel_iicbb_devclass;
630 DRIVER_MODULE_ORDERED(intel_iicbb, drmn, intel_iicbb_driver,
631     intel_iicbb_devclass, 0, 0, SI_ORDER_FIRST);
632 DRIVER_MODULE(iicbb, intel_iicbb, iicbb_driver, iicbb_devclass, 0, 0);
633 
intel_setup_gmbus(struct drm_device * dev)634 int intel_setup_gmbus(struct drm_device *dev)
635 {
636 	struct drm_i915_private *dev_priv = dev->dev_private;
637 	device_t iic_dev;
638 	int ret, i;
639 
640 	if (HAS_PCH_SPLIT(dev))
641 		dev_priv->gpio_mmio_base = PCH_GPIOA - GPIOA;
642 	else
643 		dev_priv->gpio_mmio_base = 0;
644 
645 	sx_init(&dev_priv->gmbus_sx, "gmbus");
646 
647 	/*
648 	 * The Giant there is recursed, most likely.  Normally, the
649 	 * intel_setup_gmbus() is called from the attach method of the
650 	 * driver.
651 	 */
652 	mtx_lock(&Giant);
653 	for (i = 0; i <= GMBUS_NUM_PORTS; i++) {
654 		/*
655 		 * Initialized bbbus_bridge before gmbus_bridge, since
656 		 * gmbus may decide to force quirk transfer in the
657 		 * attachment code.
658 		 */
659 		dev_priv->bbbus_bridge[i] = device_add_child(dev->dev,
660 		    "intel_iicbb", i);
661 		if (dev_priv->bbbus_bridge[i] == NULL) {
662 			DRM_ERROR("bbbus bridge %d creation failed\n", i);
663 			ret = -ENXIO;
664 			goto err;
665 		}
666 		device_quiet(dev_priv->bbbus_bridge[i]);
667 		ret = -device_probe_and_attach(dev_priv->bbbus_bridge[i]);
668 		if (ret != 0) {
669 			DRM_ERROR("bbbus bridge %d attach failed, %d\n", i,
670 			    ret);
671 			goto err;
672 		}
673 
674 		iic_dev = device_find_child(dev_priv->bbbus_bridge[i], "iicbb",
675 		    -1);
676 		if (iic_dev == NULL) {
677 			DRM_ERROR("bbbus bridge doesn't have iicbb child\n");
678 			goto err;
679 		}
680 		iic_dev = device_find_child(iic_dev, "iicbus", -1);
681 		if (iic_dev == NULL) {
682 			DRM_ERROR(
683 		"bbbus bridge doesn't have iicbus grandchild\n");
684 			goto err;
685 		}
686 
687 		dev_priv->bbbus[i] = iic_dev;
688 
689 		dev_priv->gmbus_bridge[i] = device_add_child(dev->dev,
690 		    "intel_gmbus", i);
691 		if (dev_priv->gmbus_bridge[i] == NULL) {
692 			DRM_ERROR("gmbus bridge %d creation failed\n", i);
693 			ret = -ENXIO;
694 			goto err;
695 		}
696 		device_quiet(dev_priv->gmbus_bridge[i]);
697 		ret = -device_probe_and_attach(dev_priv->gmbus_bridge[i]);
698 		if (ret != 0) {
699 			DRM_ERROR("gmbus bridge %d attach failed, %d\n", i,
700 			    ret);
701 			ret = -ENXIO;
702 			goto err;
703 		}
704 
705 		iic_dev = device_find_child(dev_priv->gmbus_bridge[i],
706 		    "iicbus", -1);
707 		if (iic_dev == NULL) {
708 			DRM_ERROR("gmbus bridge doesn't have iicbus child\n");
709 			goto err;
710 		}
711 		dev_priv->gmbus[i] = iic_dev;
712 
713 		intel_iic_reset(dev);
714 	}
715 	mtx_unlock(&Giant);
716 
717 	return 0;
718 
719 err:
720 	intel_teardown_gmbus_m(dev, i);
721 	mtx_unlock(&Giant);
722 	return ret;
723 }
724 
intel_gmbus_get_adapter(struct drm_i915_private * dev_priv,unsigned port)725 device_t intel_gmbus_get_adapter(struct drm_i915_private *dev_priv,
726 					    unsigned port)
727 {
728 
729 	if (!intel_gmbus_is_port_valid(port))
730 		DRM_ERROR("GMBUS get adapter %d: invalid port\n", port);
731 	return (intel_gmbus_is_port_valid(port) ? dev_priv->gmbus[port - 1] :
732 	    NULL);
733 }
734 
intel_gmbus_set_speed(device_t adapter,int speed)735 void intel_gmbus_set_speed(device_t adapter, int speed)
736 {
737 	struct intel_iic_softc *sc;
738 
739 	sc = device_get_softc(device_get_parent(adapter));
740 
741 	sc->reg0 = (sc->reg0 & ~(0x3 << 8)) | speed;
742 }
743 
intel_gmbus_force_bit(device_t adapter,bool force_bit)744 void intel_gmbus_force_bit(device_t adapter, bool force_bit)
745 {
746 	struct intel_iic_softc *sc;
747 
748 	sc = device_get_softc(device_get_parent(adapter));
749 	sc->force_bit_dev = force_bit;
750 }
751 
752 static void
intel_teardown_gmbus_m(struct drm_device * dev,int m)753 intel_teardown_gmbus_m(struct drm_device *dev, int m)
754 {
755 	struct drm_i915_private *dev_priv;
756 
757 	dev_priv = dev->dev_private;
758 
759 	sx_destroy(&dev_priv->gmbus_sx);
760 }
761 
intel_teardown_gmbus(struct drm_device * dev)762 void intel_teardown_gmbus(struct drm_device *dev)
763 {
764 
765 	mtx_lock(&Giant);
766 	intel_teardown_gmbus_m(dev, GMBUS_NUM_PORTS);
767 	mtx_unlock(&Giant);
768 }
769