1 /*
2  * Copyright 2013 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 #include "priv.h"
25 #include "pad.h"
26 
27 #include <core/notify.h>
28 #include <core/option.h>
29 #include <subdev/bios.h>
30 #include <subdev/bios/dcb.h>
31 
32 /******************************************************************************
33  * interface to linux i2c bit-banging algorithm
34  *****************************************************************************/
35 
36 #ifdef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT
37 #define CSTMSEL true
38 #else
39 #define CSTMSEL false
40 #endif
41 
42 static int
43 nvkm_i2c_pre_xfer(struct i2c_adapter *adap)
44 {
45 	struct i2c_algo_bit_data *bit = adap->algo_data;
46 	struct nvkm_i2c_port *port = bit->data;
47 	return nvkm_i2c(port)->acquire(port, bit->timeout);
48 }
49 
50 static void
51 nvkm_i2c_post_xfer(struct i2c_adapter *adap)
52 {
53 	struct i2c_algo_bit_data *bit = adap->algo_data;
54 	struct nvkm_i2c_port *port = bit->data;
55 	return nvkm_i2c(port)->release(port);
56 }
57 
58 static void
59 nvkm_i2c_setscl(void *data, int state)
60 {
61 	struct nvkm_i2c_port *port = data;
62 	port->func->drive_scl(port, state);
63 }
64 
65 static void
66 nvkm_i2c_setsda(void *data, int state)
67 {
68 	struct nvkm_i2c_port *port = data;
69 	port->func->drive_sda(port, state);
70 }
71 
72 static int
73 nvkm_i2c_getscl(void *data)
74 {
75 	struct nvkm_i2c_port *port = data;
76 	return port->func->sense_scl(port);
77 }
78 
79 static int
80 nvkm_i2c_getsda(void *data)
81 {
82 	struct nvkm_i2c_port *port = data;
83 	return port->func->sense_sda(port);
84 }
85 
86 /******************************************************************************
87  * base i2c "port" class implementation
88  *****************************************************************************/
89 
90 int
91 _nvkm_i2c_port_fini(struct nvkm_object *object, bool suspend)
92 {
93 	struct nvkm_i2c_port *port = (void *)object;
94 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
95 	nv_ofuncs(pad)->fini(nv_object(pad), suspend);
96 	return nvkm_object_fini(&port->base, suspend);
97 }
98 
99 void
100 _nvkm_i2c_port_dtor(struct nvkm_object *object)
101 {
102 	struct nvkm_i2c_port *port = (void *)object;
103 	i2c_del_adapter(&port->adapter);
104 	nvkm_object_destroy(&port->base);
105 }
106 
107 int
108 nvkm_i2c_port_create_(struct nvkm_object *parent, struct nvkm_object *engine,
109 		      struct nvkm_oclass *oclass, u8 index,
110 		      const struct i2c_algorithm *algo,
111 		      const struct nvkm_i2c_func *func,
112 		      int size, void **pobject)
113 {
114 	struct nvkm_device *device = nv_device(parent);
115 	struct nvkm_i2c *i2c = nvkm_i2c(parent);
116 	struct nvkm_i2c_port *port;
117 	int ret;
118 
119 	ret = nvkm_object_create_(parent, engine, oclass, 0, size, pobject);
120 	port = *pobject;
121 	if (ret)
122 		return ret;
123 
124 	snprintf(port->adapter.name, sizeof(port->adapter.name),
125 		 "nvkm-%s-%d", device->name, index);
126 	port->adapter.owner = THIS_MODULE;
127 	port->adapter.dev.parent = nv_device_base(device);
128 	port->index = index;
129 	port->aux = -1;
130 	port->func = func;
131 	mutex_init(&port->mutex);
132 
133 	if ( algo == &nvkm_i2c_bit_algo &&
134 	    !nvkm_boolopt(device->cfgopt, "NvI2C", CSTMSEL)) {
135 		struct i2c_algo_bit_data *bit;
136 
137 		bit = kzalloc(sizeof(*bit), GFP_KERNEL);
138 		if (!bit)
139 			return -ENOMEM;
140 
141 		bit->udelay = 10;
142 		bit->timeout = usecs_to_jiffies(2200);
143 		bit->data = port;
144 		bit->pre_xfer = nvkm_i2c_pre_xfer;
145 		bit->post_xfer = nvkm_i2c_post_xfer;
146 		bit->setsda = nvkm_i2c_setsda;
147 		bit->setscl = nvkm_i2c_setscl;
148 		bit->getsda = nvkm_i2c_getsda;
149 		bit->getscl = nvkm_i2c_getscl;
150 
151 		port->adapter.algo_data = bit;
152 		ret = i2c_bit_add_bus(&port->adapter);
153 	} else {
154 		port->adapter.algo_data = port;
155 		port->adapter.algo = algo;
156 		ret = i2c_add_adapter(&port->adapter);
157 	}
158 
159 	if (ret == 0)
160 		list_add_tail(&port->head, &i2c->ports);
161 	return ret;
162 }
163 
164 /******************************************************************************
165  * base i2c subdev class implementation
166  *****************************************************************************/
167 
168 static struct nvkm_i2c_port *
169 nvkm_i2c_find(struct nvkm_i2c *i2c, u8 index)
170 {
171 	struct nvkm_bios *bios = nvkm_bios(i2c);
172 	struct nvkm_i2c_port *port;
173 
174 	if (index == NV_I2C_DEFAULT(0) ||
175 	    index == NV_I2C_DEFAULT(1)) {
176 		u8  ver, hdr, cnt, len;
177 		u16 i2c = dcb_i2c_table(bios, &ver, &hdr, &cnt, &len);
178 		if (i2c && ver >= 0x30) {
179 			u8 auxidx = nvbios_rd08(bios, i2c + 4);
180 			if (index == NV_I2C_DEFAULT(0))
181 				index = (auxidx & 0x0f) >> 0;
182 			else
183 				index = (auxidx & 0xf0) >> 4;
184 		} else {
185 			index = 2;
186 		}
187 	}
188 
189 	list_for_each_entry(port, &i2c->ports, head) {
190 		if (port->index == index)
191 			return port;
192 	}
193 
194 	return NULL;
195 }
196 
197 static struct nvkm_i2c_port *
198 nvkm_i2c_find_type(struct nvkm_i2c *i2c, u16 type)
199 {
200 	struct nvkm_i2c_port *port;
201 
202 	list_for_each_entry(port, &i2c->ports, head) {
203 		if (nv_hclass(port) == type)
204 			return port;
205 	}
206 
207 	return NULL;
208 }
209 
210 static void
211 nvkm_i2c_release_pad(struct nvkm_i2c_port *port)
212 {
213 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
214 	struct nvkm_i2c *i2c = nvkm_i2c(port);
215 
216 	if (atomic_dec_and_test(&nv_object(pad)->usecount)) {
217 		nv_ofuncs(pad)->fini(nv_object(pad), false);
218 		wake_up_all(&i2c->wait);
219 	}
220 }
221 
222 static int
223 nvkm_i2c_try_acquire_pad(struct nvkm_i2c_port *port)
224 {
225 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
226 
227 	if (atomic_add_return(1, &nv_object(pad)->usecount) != 1) {
228 		struct nvkm_object *owner = (void *)pad->port;
229 		do {
230 			if (owner == (void *)port)
231 				return 0;
232 			owner = owner->parent;
233 		} while(owner);
234 		nvkm_i2c_release_pad(port);
235 		return -EBUSY;
236 	}
237 
238 	pad->next = port;
239 	nv_ofuncs(pad)->init(nv_object(pad));
240 	return 0;
241 }
242 
243 static int
244 nvkm_i2c_acquire_pad(struct nvkm_i2c_port *port, unsigned long timeout)
245 {
246 	struct nvkm_i2c *i2c = nvkm_i2c(port);
247 
248 	if (timeout) {
249 		if (wait_event_timeout(i2c->wait,
250 				       nvkm_i2c_try_acquire_pad(port) == 0,
251 				       timeout) == 0)
252 			return -EBUSY;
253 	} else {
254 		wait_event(i2c->wait, nvkm_i2c_try_acquire_pad(port) == 0);
255 	}
256 
257 	return 0;
258 }
259 
260 static void
261 nvkm_i2c_release(struct nvkm_i2c_port *port)
262 __releases(pad->mutex)
263 {
264 	nvkm_i2c(port)->release_pad(port);
265 	mutex_unlock(&port->mutex);
266 }
267 
268 static int
269 nvkm_i2c_acquire(struct nvkm_i2c_port *port, unsigned long timeout)
270 __acquires(pad->mutex)
271 {
272 	int ret;
273 	mutex_lock(&port->mutex);
274 	if ((ret = nvkm_i2c(port)->acquire_pad(port, timeout)))
275 		mutex_unlock(&port->mutex);
276 	return ret;
277 }
278 
279 static int
280 nvkm_i2c_identify(struct nvkm_i2c *i2c, int index, const char *what,
281 		  struct nvkm_i2c_board_info *info,
282 		  bool (*match)(struct nvkm_i2c_port *,
283 				struct i2c_board_info *, void *), void *data)
284 {
285 	struct nvkm_subdev *subdev = &i2c->subdev;
286 	struct nvkm_i2c_port *port = nvkm_i2c_find(i2c, index);
287 	int i;
288 
289 	if (!port) {
290 		nvkm_debug(subdev, "no bus when probing %s on %d\n",
291 			   what, index);
292 		return -ENODEV;
293 	}
294 
295 	nvkm_debug(subdev, "probing %ss on bus: %d\n", what, port->index);
296 	for (i = 0; info[i].dev.addr; i++) {
297 		u8 orig_udelay = 0;
298 
299 		if ((port->adapter.algo == &i2c_bit_algo) &&
300 		    (info[i].udelay != 0)) {
301 			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
302 			nvkm_debug(subdev,
303 				   "using custom udelay %d instead of %d\n",
304 				   info[i].udelay, algo->udelay);
305 			orig_udelay = algo->udelay;
306 			algo->udelay = info[i].udelay;
307 		}
308 
309 		if (nv_probe_i2c(port, info[i].dev.addr) &&
310 		    (!match || match(port, &info[i].dev, data))) {
311 			nvkm_info(subdev, "detected %s: %s\n", what,
312 				  info[i].dev.type);
313 			return i;
314 		}
315 
316 		if (orig_udelay) {
317 			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
318 			algo->udelay = orig_udelay;
319 		}
320 	}
321 
322 	nvkm_debug(subdev, "no devices found.\n");
323 	return -ENODEV;
324 }
325 
326 static void
327 nvkm_i2c_intr_fini(struct nvkm_event *event, int type, int index)
328 {
329 	struct nvkm_i2c *i2c = container_of(event, typeof(*i2c), event);
330 	struct nvkm_i2c_port *port = i2c->find(i2c, index);
331 	const struct nvkm_i2c_impl *impl = (void *)nv_object(i2c)->oclass;
332 	if (port && port->aux >= 0)
333 		impl->aux_mask(i2c, type, 1 << port->aux, 0);
334 }
335 
336 static void
337 nvkm_i2c_intr_init(struct nvkm_event *event, int type, int index)
338 {
339 	struct nvkm_i2c *i2c = container_of(event, typeof(*i2c), event);
340 	struct nvkm_i2c_port *port = i2c->find(i2c, index);
341 	const struct nvkm_i2c_impl *impl = (void *)nv_object(i2c)->oclass;
342 	if (port && port->aux >= 0)
343 		impl->aux_mask(i2c, type, 1 << port->aux, 1 << port->aux);
344 }
345 
346 static int
347 nvkm_i2c_intr_ctor(struct nvkm_object *object, void *data, u32 size,
348 		      struct nvkm_notify *notify)
349 {
350 	struct nvkm_i2c_ntfy_req *req = data;
351 	if (!WARN_ON(size != sizeof(*req))) {
352 		notify->size  = sizeof(struct nvkm_i2c_ntfy_rep);
353 		notify->types = req->mask;
354 		notify->index = req->port;
355 		return 0;
356 	}
357 	return -EINVAL;
358 }
359 
360 static void
361 nvkm_i2c_intr(struct nvkm_subdev *subdev)
362 {
363 	struct nvkm_i2c_impl *impl = (void *)nv_oclass(subdev);
364 	struct nvkm_i2c *i2c = nvkm_i2c(subdev);
365 	struct nvkm_i2c_port *port;
366 	u32 hi, lo, rq, tx, e;
367 
368 	if (impl->aux_stat) {
369 		impl->aux_stat(i2c, &hi, &lo, &rq, &tx);
370 		if (hi || lo || rq || tx) {
371 			list_for_each_entry(port, &i2c->ports, head) {
372 				if (e = 0, port->aux < 0)
373 					continue;
374 
375 				if (hi & (1 << port->aux)) e |= NVKM_I2C_PLUG;
376 				if (lo & (1 << port->aux)) e |= NVKM_I2C_UNPLUG;
377 				if (rq & (1 << port->aux)) e |= NVKM_I2C_IRQ;
378 				if (tx & (1 << port->aux)) e |= NVKM_I2C_DONE;
379 				if (e) {
380 					struct nvkm_i2c_ntfy_rep rep = {
381 						.mask = e,
382 					};
383 					nvkm_event_send(&i2c->event, rep.mask,
384 							port->index, &rep,
385 							sizeof(rep));
386 				}
387 			}
388 		}
389 	}
390 }
391 
392 static const struct nvkm_event_func
393 nvkm_i2c_intr_func = {
394 	.ctor = nvkm_i2c_intr_ctor,
395 	.init = nvkm_i2c_intr_init,
396 	.fini = nvkm_i2c_intr_fini,
397 };
398 
399 int
400 _nvkm_i2c_fini(struct nvkm_object *object, bool suspend)
401 {
402 	struct nvkm_i2c_impl *impl = (void *)nv_oclass(object);
403 	struct nvkm_i2c *i2c = (void *)object;
404 	struct nvkm_i2c_port *port;
405 	u32 mask;
406 	int ret;
407 
408 	list_for_each_entry(port, &i2c->ports, head) {
409 		ret = nv_ofuncs(port)->fini(nv_object(port), suspend);
410 		if (ret && suspend)
411 			goto fail;
412 	}
413 
414 	if ((mask = (1 << impl->aux) - 1), impl->aux_stat) {
415 		impl->aux_mask(i2c, NVKM_I2C_ANY, mask, 0);
416 		impl->aux_stat(i2c, &mask, &mask, &mask, &mask);
417 	}
418 
419 	return nvkm_subdev_fini(&i2c->subdev, suspend);
420 fail:
421 	list_for_each_entry_continue_reverse(port, &i2c->ports, head) {
422 		nv_ofuncs(port)->init(nv_object(port));
423 	}
424 
425 	return ret;
426 }
427 
428 int
429 _nvkm_i2c_init(struct nvkm_object *object)
430 {
431 	struct nvkm_i2c *i2c = (void *)object;
432 	struct nvkm_i2c_port *port;
433 	int ret;
434 
435 	ret = nvkm_subdev_init(&i2c->subdev);
436 	if (ret == 0) {
437 		list_for_each_entry(port, &i2c->ports, head) {
438 			ret = nv_ofuncs(port)->init(nv_object(port));
439 			if (ret)
440 				goto fail;
441 		}
442 	}
443 
444 	return ret;
445 fail:
446 	list_for_each_entry_continue_reverse(port, &i2c->ports, head) {
447 		nv_ofuncs(port)->fini(nv_object(port), false);
448 	}
449 
450 	return ret;
451 }
452 
453 void
454 _nvkm_i2c_dtor(struct nvkm_object *object)
455 {
456 	struct nvkm_i2c *i2c = (void *)object;
457 	struct nvkm_i2c_port *port, *temp;
458 
459 	nvkm_event_fini(&i2c->event);
460 
461 	list_for_each_entry_safe(port, temp, &i2c->ports, head) {
462 		nvkm_object_ref(NULL, (struct nvkm_object **)&port);
463 	}
464 
465 	nvkm_subdev_destroy(&i2c->subdev);
466 }
467 
468 static struct nvkm_oclass *
469 nvkm_i2c_extdev_sclass[] = {
470 	nvkm_anx9805_sclass,
471 };
472 
473 static void
474 nvkm_i2c_create_port(struct nvkm_i2c *i2c, int index, u8 type,
475 		     struct dcb_i2c_entry *info)
476 {
477 	const struct nvkm_i2c_impl *impl = (void *)nv_oclass(i2c);
478 	struct nvkm_oclass *oclass;
479 	struct nvkm_object *parent;
480 	struct nvkm_object *object;
481 	int ret, pad;
482 
483 	if (info->share != DCB_I2C_UNUSED) {
484 		pad    = info->share;
485 		oclass = impl->pad_s;
486 	} else {
487 		if (type != DCB_I2C_NVIO_AUX)
488 			pad = 0x100 + info->drive;
489 		else
490 			pad = 0x100 + info->auxch;
491 		oclass = impl->pad_x;
492 	}
493 
494 	ret = nvkm_object_ctor(nv_object(i2c), NULL, oclass,
495 			       NULL, pad, &parent);
496 	if (ret < 0)
497 		return;
498 
499 	oclass = impl->sclass;
500 	do {
501 		ret = -EINVAL;
502 		if (oclass->handle == type) {
503 			ret = nvkm_object_ctor(parent, NULL, oclass,
504 					       info, index, &object);
505 		}
506 	} while (ret && (++oclass)->handle);
507 
508 	nvkm_object_ref(NULL, &parent);
509 }
510 
511 int
512 nvkm_i2c_create_(struct nvkm_object *parent, struct nvkm_object *engine,
513 		 struct nvkm_oclass *oclass, int length, void **pobject)
514 {
515 	struct nvkm_bios *bios = nvkm_bios(parent);
516 	struct nvkm_i2c *i2c;
517 	struct nvkm_object *object;
518 	struct dcb_i2c_entry info;
519 	int ret, i, j, index = -1;
520 	struct dcb_output outp;
521 	u8  ver, hdr;
522 	u32 data;
523 
524 	ret = nvkm_subdev_create(parent, engine, oclass, 0, "I2C", "i2c", &i2c);
525 	*pobject = nv_object(i2c);
526 	if (ret)
527 		return ret;
528 
529 	nv_subdev(i2c)->intr = nvkm_i2c_intr;
530 	i2c->find = nvkm_i2c_find;
531 	i2c->find_type = nvkm_i2c_find_type;
532 	i2c->acquire_pad = nvkm_i2c_acquire_pad;
533 	i2c->release_pad = nvkm_i2c_release_pad;
534 	i2c->acquire = nvkm_i2c_acquire;
535 	i2c->release = nvkm_i2c_release;
536 	i2c->identify = nvkm_i2c_identify;
537 	init_waitqueue_head(&i2c->wait);
538 	INIT_LIST_HEAD(&i2c->ports);
539 
540 	while (!dcb_i2c_parse(bios, ++index, &info)) {
541 		switch (info.type) {
542 		case DCB_I2C_NV04_BIT:
543 		case DCB_I2C_NV4E_BIT:
544 		case DCB_I2C_NVIO_BIT:
545 			nvkm_i2c_create_port(i2c, NV_I2C_PORT(index),
546 					     info.type, &info);
547 			break;
548 		case DCB_I2C_NVIO_AUX:
549 			nvkm_i2c_create_port(i2c, NV_I2C_AUX(index),
550 					     info.type, &info);
551 			break;
552 		case DCB_I2C_PMGR:
553 			if (info.drive != DCB_I2C_UNUSED) {
554 				nvkm_i2c_create_port(i2c, NV_I2C_PORT(index),
555 						     DCB_I2C_NVIO_BIT, &info);
556 			}
557 			if (info.auxch != DCB_I2C_UNUSED) {
558 				nvkm_i2c_create_port(i2c, NV_I2C_AUX(index),
559 						     DCB_I2C_NVIO_AUX, &info);
560 			}
561 			break;
562 		case DCB_I2C_UNUSED:
563 		default:
564 			continue;
565 		}
566 	}
567 
568 	/* in addition to the busses specified in the i2c table, there
569 	 * may be ddc/aux channels hiding behind external tmds/dp/etc
570 	 * transmitters.
571 	 */
572 	index = NV_I2C_EXT(0);
573 	i = -1;
574 	while ((data = dcb_outp_parse(bios, ++i, &ver, &hdr, &outp))) {
575 		if (!outp.location || !outp.extdev)
576 			continue;
577 
578 		switch (outp.type) {
579 		case DCB_OUTPUT_TMDS:
580 			info.type = NV_I2C_TYPE_EXTDDC(outp.extdev);
581 			break;
582 		case DCB_OUTPUT_DP:
583 			info.type = NV_I2C_TYPE_EXTAUX(outp.extdev);
584 			break;
585 		default:
586 			continue;
587 		}
588 
589 		ret = -ENODEV;
590 		j = -1;
591 		while (ret && ++j < ARRAY_SIZE(nvkm_i2c_extdev_sclass)) {
592 			parent = nv_object(i2c->find(i2c, outp.i2c_index));
593 			oclass = nvkm_i2c_extdev_sclass[j];
594 			do {
595 				if (oclass->handle != info.type)
596 					continue;
597 				ret = nvkm_object_ctor(parent, NULL, oclass,
598 						       NULL, index++, &object);
599 			} while (ret && (++oclass)->handle);
600 		}
601 	}
602 
603 	ret = nvkm_event_init(&nvkm_i2c_intr_func, 4, index, &i2c->event);
604 	if (ret)
605 		return ret;
606 
607 	return 0;
608 }
609 
610 int
611 _nvkm_i2c_ctor(struct nvkm_object *parent, struct nvkm_object *engine,
612 	       struct nvkm_oclass *oclass, void *data, u32 size,
613 	       struct nvkm_object **pobject)
614 {
615 	struct nvkm_i2c *i2c;
616 	int ret;
617 
618 	ret = nvkm_i2c_create(parent, engine, oclass, &i2c);
619 	*pobject = nv_object(i2c);
620 	if (ret)
621 		return ret;
622 
623 	return 0;
624 }
625