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/device.h>
28 #include <core/notify.h>
29 #include <core/option.h>
30 #include <subdev/bios.h>
31 #include <subdev/bios/dcb.h>
32 
33 /******************************************************************************
34  * interface to linux i2c bit-banging algorithm
35  *****************************************************************************/
36 
37 #ifdef CONFIG_NOUVEAU_I2C_INTERNAL_DEFAULT
38 #define CSTMSEL true
39 #else
40 #define CSTMSEL false
41 #endif
42 
43 static int
44 nvkm_i2c_pre_xfer(struct i2c_adapter *adap)
45 {
46 	struct i2c_algo_bit_data *bit = adap->algo_data;
47 	struct nvkm_i2c_port *port = bit->data;
48 	return nvkm_i2c(port)->acquire(port, bit->timeout);
49 }
50 
51 static void
52 nvkm_i2c_post_xfer(struct i2c_adapter *adap)
53 {
54 	struct i2c_algo_bit_data *bit = adap->algo_data;
55 	struct nvkm_i2c_port *port = bit->data;
56 	return nvkm_i2c(port)->release(port);
57 }
58 
59 static void
60 nvkm_i2c_setscl(void *data, int state)
61 {
62 	struct nvkm_i2c_port *port = data;
63 	port->func->drive_scl(port, state);
64 }
65 
66 static void
67 nvkm_i2c_setsda(void *data, int state)
68 {
69 	struct nvkm_i2c_port *port = data;
70 	port->func->drive_sda(port, state);
71 }
72 
73 static int
74 nvkm_i2c_getscl(void *data)
75 {
76 	struct nvkm_i2c_port *port = data;
77 	return port->func->sense_scl(port);
78 }
79 
80 static int
81 nvkm_i2c_getsda(void *data)
82 {
83 	struct nvkm_i2c_port *port = data;
84 	return port->func->sense_sda(port);
85 }
86 
87 /******************************************************************************
88  * base i2c "port" class implementation
89  *****************************************************************************/
90 
91 int
92 _nvkm_i2c_port_fini(struct nvkm_object *object, bool suspend)
93 {
94 	struct nvkm_i2c_port *port = (void *)object;
95 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
96 	nv_ofuncs(pad)->fini(nv_object(pad), suspend);
97 	return nvkm_object_fini(&port->base, suspend);
98 }
99 
100 void
101 _nvkm_i2c_port_dtor(struct nvkm_object *object)
102 {
103 	struct nvkm_i2c_port *port = (void *)object;
104 	i2c_del_adapter(&port->adapter);
105 	nvkm_object_destroy(&port->base);
106 }
107 
108 int
109 nvkm_i2c_port_create_(struct nvkm_object *parent, struct nvkm_object *engine,
110 		      struct nvkm_oclass *oclass, u8 index,
111 		      const struct i2c_algorithm *algo,
112 		      const struct nvkm_i2c_func *func,
113 		      int size, void **pobject)
114 {
115 	struct nvkm_device *device = nv_device(parent);
116 	struct nvkm_i2c *i2c = nvkm_i2c(parent);
117 	struct nvkm_i2c_port *port;
118 	int ret;
119 
120 	ret = nvkm_object_create_(parent, engine, oclass, 0, size, pobject);
121 	port = *pobject;
122 	if (ret)
123 		return ret;
124 
125 	snprintf(port->adapter.name, sizeof(port->adapter.name),
126 		 "nvkm-%s-%d", device->name, index);
127 	port->adapter.owner = THIS_MODULE;
128 	port->adapter.dev.parent = nv_device_base(device);
129 	port->index = index;
130 	port->aux = -1;
131 	port->func = func;
132 	mutex_init(&port->mutex);
133 
134 	if ( algo == &nvkm_i2c_bit_algo &&
135 	    !nvkm_boolopt(device->cfgopt, "NvI2C", CSTMSEL)) {
136 		struct i2c_algo_bit_data *bit;
137 
138 		bit = kzalloc(sizeof(*bit), GFP_KERNEL);
139 		if (!bit)
140 			return -ENOMEM;
141 
142 		bit->udelay = 10;
143 		bit->timeout = usecs_to_jiffies(2200);
144 		bit->data = port;
145 		bit->pre_xfer = nvkm_i2c_pre_xfer;
146 		bit->post_xfer = nvkm_i2c_post_xfer;
147 		bit->setsda = nvkm_i2c_setsda;
148 		bit->setscl = nvkm_i2c_setscl;
149 		bit->getsda = nvkm_i2c_getsda;
150 		bit->getscl = nvkm_i2c_getscl;
151 
152 		port->adapter.algo_data = bit;
153 		ret = i2c_bit_add_bus(&port->adapter);
154 	} else {
155 		port->adapter.algo_data = port;
156 		port->adapter.algo = algo;
157 		ret = i2c_add_adapter(&port->adapter);
158 	}
159 
160 	if (ret == 0)
161 		list_add_tail(&port->head, &i2c->ports);
162 	return ret;
163 }
164 
165 /******************************************************************************
166  * base i2c subdev class implementation
167  *****************************************************************************/
168 
169 static struct nvkm_i2c_port *
170 nvkm_i2c_find(struct nvkm_i2c *i2c, u8 index)
171 {
172 	struct nvkm_bios *bios = nvkm_bios(i2c);
173 	struct nvkm_i2c_port *port;
174 
175 	if (index == NV_I2C_DEFAULT(0) ||
176 	    index == NV_I2C_DEFAULT(1)) {
177 		u8  ver, hdr, cnt, len;
178 		u16 i2c = dcb_i2c_table(bios, &ver, &hdr, &cnt, &len);
179 		if (i2c && ver >= 0x30) {
180 			u8 auxidx = nv_ro08(bios, i2c + 4);
181 			if (index == NV_I2C_DEFAULT(0))
182 				index = (auxidx & 0x0f) >> 0;
183 			else
184 				index = (auxidx & 0xf0) >> 4;
185 		} else {
186 			index = 2;
187 		}
188 	}
189 
190 	list_for_each_entry(port, &i2c->ports, head) {
191 		if (port->index == index)
192 			return port;
193 	}
194 
195 	return NULL;
196 }
197 
198 static struct nvkm_i2c_port *
199 nvkm_i2c_find_type(struct nvkm_i2c *i2c, u16 type)
200 {
201 	struct nvkm_i2c_port *port;
202 
203 	list_for_each_entry(port, &i2c->ports, head) {
204 		if (nv_hclass(port) == type)
205 			return port;
206 	}
207 
208 	return NULL;
209 }
210 
211 static void
212 nvkm_i2c_release_pad(struct nvkm_i2c_port *port)
213 {
214 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
215 	struct nvkm_i2c *i2c = nvkm_i2c(port);
216 
217 	if (atomic_dec_and_test(&nv_object(pad)->usecount)) {
218 		nv_ofuncs(pad)->fini(nv_object(pad), false);
219 		wake_up_all(&i2c->wait);
220 	}
221 }
222 
223 static int
224 nvkm_i2c_try_acquire_pad(struct nvkm_i2c_port *port)
225 {
226 	struct nvkm_i2c_pad *pad = nvkm_i2c_pad(port);
227 
228 	if (atomic_add_return(1, &nv_object(pad)->usecount) != 1) {
229 		struct nvkm_object *owner = (void *)pad->port;
230 		do {
231 			if (owner == (void *)port)
232 				return 0;
233 			owner = owner->parent;
234 		} while(owner);
235 		nvkm_i2c_release_pad(port);
236 		return -EBUSY;
237 	}
238 
239 	pad->next = port;
240 	nv_ofuncs(pad)->init(nv_object(pad));
241 	return 0;
242 }
243 
244 static int
245 nvkm_i2c_acquire_pad(struct nvkm_i2c_port *port, unsigned long timeout)
246 {
247 	struct nvkm_i2c *i2c = nvkm_i2c(port);
248 
249 	if (timeout) {
250 		if (wait_event_timeout(i2c->wait,
251 				       nvkm_i2c_try_acquire_pad(port) == 0,
252 				       timeout) == 0)
253 			return -EBUSY;
254 	} else {
255 		wait_event(i2c->wait, nvkm_i2c_try_acquire_pad(port) == 0);
256 	}
257 
258 	return 0;
259 }
260 
261 static void
262 nvkm_i2c_release(struct nvkm_i2c_port *port)
263 __releases(pad->mutex)
264 {
265 	nvkm_i2c(port)->release_pad(port);
266 	mutex_unlock(&port->mutex);
267 }
268 
269 static int
270 nvkm_i2c_acquire(struct nvkm_i2c_port *port, unsigned long timeout)
271 __acquires(pad->mutex)
272 {
273 	int ret;
274 	mutex_lock(&port->mutex);
275 	if ((ret = nvkm_i2c(port)->acquire_pad(port, timeout)))
276 		mutex_unlock(&port->mutex);
277 	return ret;
278 }
279 
280 static int
281 nvkm_i2c_identify(struct nvkm_i2c *i2c, int index, const char *what,
282 		  struct nvkm_i2c_board_info *info,
283 		  bool (*match)(struct nvkm_i2c_port *,
284 				struct i2c_board_info *, void *), void *data)
285 {
286 	struct nvkm_i2c_port *port = nvkm_i2c_find(i2c, index);
287 	int i;
288 
289 	if (!port) {
290 		nv_debug(i2c, "no bus when probing %s on %d\n", what, index);
291 		return -ENODEV;
292 	}
293 
294 	nv_debug(i2c, "probing %ss on bus: %d\n", what, port->index);
295 	for (i = 0; info[i].dev.addr; i++) {
296 		u8 orig_udelay = 0;
297 
298 		if ((port->adapter.algo == &i2c_bit_algo) &&
299 		    (info[i].udelay != 0)) {
300 			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
301 			nv_debug(i2c, "using custom udelay %d instead of %d\n",
302 			         info[i].udelay, algo->udelay);
303 			orig_udelay = algo->udelay;
304 			algo->udelay = info[i].udelay;
305 		}
306 
307 		if (nv_probe_i2c(port, info[i].dev.addr) &&
308 		    (!match || match(port, &info[i].dev, data))) {
309 			nv_info(i2c, "detected %s: %s\n", what,
310 				info[i].dev.type);
311 			return i;
312 		}
313 
314 		if (orig_udelay) {
315 			struct i2c_algo_bit_data *algo = port->adapter.algo_data;
316 			algo->udelay = orig_udelay;
317 		}
318 	}
319 
320 	nv_debug(i2c, "no devices found.\n");
321 	return -ENODEV;
322 }
323 
324 static void
325 nvkm_i2c_intr_fini(struct nvkm_event *event, int type, int index)
326 {
327 	struct nvkm_i2c *i2c = container_of(event, typeof(*i2c), event);
328 	struct nvkm_i2c_port *port = i2c->find(i2c, index);
329 	const struct nvkm_i2c_impl *impl = (void *)nv_object(i2c)->oclass;
330 	if (port && port->aux >= 0)
331 		impl->aux_mask(i2c, type, 1 << port->aux, 0);
332 }
333 
334 static void
335 nvkm_i2c_intr_init(struct nvkm_event *event, int type, int index)
336 {
337 	struct nvkm_i2c *i2c = container_of(event, typeof(*i2c), event);
338 	struct nvkm_i2c_port *port = i2c->find(i2c, index);
339 	const struct nvkm_i2c_impl *impl = (void *)nv_object(i2c)->oclass;
340 	if (port && port->aux >= 0)
341 		impl->aux_mask(i2c, type, 1 << port->aux, 1 << port->aux);
342 }
343 
344 static int
345 nvkm_i2c_intr_ctor(struct nvkm_object *object, void *data, u32 size,
346 		      struct nvkm_notify *notify)
347 {
348 	struct nvkm_i2c_ntfy_req *req = data;
349 	if (!WARN_ON(size != sizeof(*req))) {
350 		notify->size  = sizeof(struct nvkm_i2c_ntfy_rep);
351 		notify->types = req->mask;
352 		notify->index = req->port;
353 		return 0;
354 	}
355 	return -EINVAL;
356 }
357 
358 static void
359 nvkm_i2c_intr(struct nvkm_subdev *subdev)
360 {
361 	struct nvkm_i2c_impl *impl = (void *)nv_oclass(subdev);
362 	struct nvkm_i2c *i2c = nvkm_i2c(subdev);
363 	struct nvkm_i2c_port *port;
364 	u32 hi, lo, rq, tx, e;
365 
366 	if (impl->aux_stat) {
367 		impl->aux_stat(i2c, &hi, &lo, &rq, &tx);
368 		if (hi || lo || rq || tx) {
369 			list_for_each_entry(port, &i2c->ports, head) {
370 				if (e = 0, port->aux < 0)
371 					continue;
372 
373 				if (hi & (1 << port->aux)) e |= NVKM_I2C_PLUG;
374 				if (lo & (1 << port->aux)) e |= NVKM_I2C_UNPLUG;
375 				if (rq & (1 << port->aux)) e |= NVKM_I2C_IRQ;
376 				if (tx & (1 << port->aux)) e |= NVKM_I2C_DONE;
377 				if (e) {
378 					struct nvkm_i2c_ntfy_rep rep = {
379 						.mask = e,
380 					};
381 					nvkm_event_send(&i2c->event, rep.mask,
382 							port->index, &rep,
383 							sizeof(rep));
384 				}
385 			}
386 		}
387 	}
388 }
389 
390 static const struct nvkm_event_func
391 nvkm_i2c_intr_func = {
392 	.ctor = nvkm_i2c_intr_ctor,
393 	.init = nvkm_i2c_intr_init,
394 	.fini = nvkm_i2c_intr_fini,
395 };
396 
397 int
398 _nvkm_i2c_fini(struct nvkm_object *object, bool suspend)
399 {
400 	struct nvkm_i2c_impl *impl = (void *)nv_oclass(object);
401 	struct nvkm_i2c *i2c = (void *)object;
402 	struct nvkm_i2c_port *port;
403 	u32 mask;
404 	int ret;
405 
406 	list_for_each_entry(port, &i2c->ports, head) {
407 		ret = nv_ofuncs(port)->fini(nv_object(port), suspend);
408 		if (ret && suspend)
409 			goto fail;
410 	}
411 
412 	if ((mask = (1 << impl->aux) - 1), impl->aux_stat) {
413 		impl->aux_mask(i2c, NVKM_I2C_ANY, mask, 0);
414 		impl->aux_stat(i2c, &mask, &mask, &mask, &mask);
415 	}
416 
417 	return nvkm_subdev_fini(&i2c->base, suspend);
418 fail:
419 	list_for_each_entry_continue_reverse(port, &i2c->ports, head) {
420 		nv_ofuncs(port)->init(nv_object(port));
421 	}
422 
423 	return ret;
424 }
425 
426 int
427 _nvkm_i2c_init(struct nvkm_object *object)
428 {
429 	struct nvkm_i2c *i2c = (void *)object;
430 	struct nvkm_i2c_port *port;
431 	int ret;
432 
433 	ret = nvkm_subdev_init(&i2c->base);
434 	if (ret == 0) {
435 		list_for_each_entry(port, &i2c->ports, head) {
436 			ret = nv_ofuncs(port)->init(nv_object(port));
437 			if (ret)
438 				goto fail;
439 		}
440 	}
441 
442 	return ret;
443 fail:
444 	list_for_each_entry_continue_reverse(port, &i2c->ports, head) {
445 		nv_ofuncs(port)->fini(nv_object(port), false);
446 	}
447 
448 	return ret;
449 }
450 
451 void
452 _nvkm_i2c_dtor(struct nvkm_object *object)
453 {
454 	struct nvkm_i2c *i2c = (void *)object;
455 	struct nvkm_i2c_port *port, *temp;
456 
457 	nvkm_event_fini(&i2c->event);
458 
459 	list_for_each_entry_safe(port, temp, &i2c->ports, head) {
460 		nvkm_object_ref(NULL, (struct nvkm_object **)&port);
461 	}
462 
463 	nvkm_subdev_destroy(&i2c->base);
464 }
465 
466 static struct nvkm_oclass *
467 nvkm_i2c_extdev_sclass[] = {
468 	nvkm_anx9805_sclass,
469 };
470 
471 static void
472 nvkm_i2c_create_port(struct nvkm_i2c *i2c, int index, u8 type,
473 		     struct dcb_i2c_entry *info)
474 {
475 	const struct nvkm_i2c_impl *impl = (void *)nv_oclass(i2c);
476 	struct nvkm_oclass *oclass;
477 	struct nvkm_object *parent;
478 	struct nvkm_object *object;
479 	int ret, pad;
480 
481 	if (info->share != DCB_I2C_UNUSED) {
482 		pad    = info->share;
483 		oclass = impl->pad_s;
484 	} else {
485 		if (type != DCB_I2C_NVIO_AUX)
486 			pad = 0x100 + info->drive;
487 		else
488 			pad = 0x100 + info->auxch;
489 		oclass = impl->pad_x;
490 	}
491 
492 	ret = nvkm_object_ctor(nv_object(i2c), NULL, oclass,
493 			       NULL, pad, &parent);
494 	if (ret < 0)
495 		return;
496 
497 	oclass = impl->sclass;
498 	do {
499 		ret = -EINVAL;
500 		if (oclass->handle == type) {
501 			ret = nvkm_object_ctor(parent, NULL, oclass,
502 					       info, index, &object);
503 		}
504 	} while (ret && (++oclass)->handle);
505 
506 	nvkm_object_ref(NULL, &parent);
507 }
508 
509 int
510 nvkm_i2c_create_(struct nvkm_object *parent, struct nvkm_object *engine,
511 		 struct nvkm_oclass *oclass, int length, void **pobject)
512 {
513 	struct nvkm_bios *bios = nvkm_bios(parent);
514 	struct nvkm_i2c *i2c;
515 	struct nvkm_object *object;
516 	struct dcb_i2c_entry info;
517 	int ret, i, j, index = -1;
518 	struct dcb_output outp;
519 	u8  ver, hdr;
520 	u32 data;
521 
522 	ret = nvkm_subdev_create(parent, engine, oclass, 0, "I2C", "i2c", &i2c);
523 	*pobject = nv_object(i2c);
524 	if (ret)
525 		return ret;
526 
527 	nv_subdev(i2c)->intr = nvkm_i2c_intr;
528 	i2c->find = nvkm_i2c_find;
529 	i2c->find_type = nvkm_i2c_find_type;
530 	i2c->acquire_pad = nvkm_i2c_acquire_pad;
531 	i2c->release_pad = nvkm_i2c_release_pad;
532 	i2c->acquire = nvkm_i2c_acquire;
533 	i2c->release = nvkm_i2c_release;
534 	i2c->identify = nvkm_i2c_identify;
535 	init_waitqueue_head(&i2c->wait);
536 	INIT_LIST_HEAD(&i2c->ports);
537 
538 	while (!dcb_i2c_parse(bios, ++index, &info)) {
539 		switch (info.type) {
540 		case DCB_I2C_NV04_BIT:
541 		case DCB_I2C_NV4E_BIT:
542 		case DCB_I2C_NVIO_BIT:
543 			nvkm_i2c_create_port(i2c, NV_I2C_PORT(index),
544 					     info.type, &info);
545 			break;
546 		case DCB_I2C_NVIO_AUX:
547 			nvkm_i2c_create_port(i2c, NV_I2C_AUX(index),
548 					     info.type, &info);
549 			break;
550 		case DCB_I2C_PMGR:
551 			if (info.drive != DCB_I2C_UNUSED) {
552 				nvkm_i2c_create_port(i2c, NV_I2C_PORT(index),
553 						     DCB_I2C_NVIO_BIT, &info);
554 			}
555 			if (info.auxch != DCB_I2C_UNUSED) {
556 				nvkm_i2c_create_port(i2c, NV_I2C_AUX(index),
557 						     DCB_I2C_NVIO_AUX, &info);
558 			}
559 			break;
560 		case DCB_I2C_UNUSED:
561 		default:
562 			continue;
563 		}
564 	}
565 
566 	/* in addition to the busses specified in the i2c table, there
567 	 * may be ddc/aux channels hiding behind external tmds/dp/etc
568 	 * transmitters.
569 	 */
570 	index = NV_I2C_EXT(0);
571 	i = -1;
572 	while ((data = dcb_outp_parse(bios, ++i, &ver, &hdr, &outp))) {
573 		if (!outp.location || !outp.extdev)
574 			continue;
575 
576 		switch (outp.type) {
577 		case DCB_OUTPUT_TMDS:
578 			info.type = NV_I2C_TYPE_EXTDDC(outp.extdev);
579 			break;
580 		case DCB_OUTPUT_DP:
581 			info.type = NV_I2C_TYPE_EXTAUX(outp.extdev);
582 			break;
583 		default:
584 			continue;
585 		}
586 
587 		ret = -ENODEV;
588 		j = -1;
589 		while (ret && ++j < ARRAY_SIZE(nvkm_i2c_extdev_sclass)) {
590 			parent = nv_object(i2c->find(i2c, outp.i2c_index));
591 			oclass = nvkm_i2c_extdev_sclass[j];
592 			do {
593 				if (oclass->handle != info.type)
594 					continue;
595 				ret = nvkm_object_ctor(parent, NULL, oclass,
596 						       NULL, index++, &object);
597 			} while (ret && (++oclass)->handle);
598 		}
599 	}
600 
601 	ret = nvkm_event_init(&nvkm_i2c_intr_func, 4, index, &i2c->event);
602 	if (ret)
603 		return ret;
604 
605 	return 0;
606 }
607 
608 int
609 _nvkm_i2c_ctor(struct nvkm_object *parent, struct nvkm_object *engine,
610 	       struct nvkm_oclass *oclass, void *data, u32 size,
611 	       struct nvkm_object **pobject)
612 {
613 	struct nvkm_i2c *i2c;
614 	int ret;
615 
616 	ret = nvkm_i2c_create(parent, engine, oclass, &i2c);
617 	*pobject = nv_object(i2c);
618 	if (ret)
619 		return ret;
620 
621 	return 0;
622 }
623