1 /*
2 * Copyright 2009 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
25 #include <linux/module.h>
26
27 #include "drmP.h"
28 #include "nouveau_drv.h"
29 #include "nouveau_i2c.h"
30 #include "nouveau_hw.h"
31
32 #define T_TIMEOUT 2200000
33 #define T_RISEFALL 1000
34 #define T_HOLD 5000
35
36 static void
i2c_drive_scl(void * data,int state)37 i2c_drive_scl(void *data, int state)
38 {
39 struct nouveau_i2c_chan *port = data;
40 if (port->type == 0) {
41 u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
42 if (state) val |= 0x20;
43 else val &= 0xdf;
44 NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
45 } else
46 if (port->type == 4) {
47 nv_mask(port->dev, port->drive, 0x2f, state ? 0x21 : 0x01);
48 } else
49 if (port->type == 5) {
50 if (state) port->state |= 0x01;
51 else port->state &= 0xfe;
52 nv_wr32(port->dev, port->drive, 4 | port->state);
53 }
54 }
55
56 static void
i2c_drive_sda(void * data,int state)57 i2c_drive_sda(void *data, int state)
58 {
59 struct nouveau_i2c_chan *port = data;
60 if (port->type == 0) {
61 u8 val = NVReadVgaCrtc(port->dev, 0, port->drive);
62 if (state) val |= 0x10;
63 else val &= 0xef;
64 NVWriteVgaCrtc(port->dev, 0, port->drive, val | 0x01);
65 } else
66 if (port->type == 4) {
67 nv_mask(port->dev, port->drive, 0x1f, state ? 0x11 : 0x01);
68 } else
69 if (port->type == 5) {
70 if (state) port->state |= 0x02;
71 else port->state &= 0xfd;
72 nv_wr32(port->dev, port->drive, 4 | port->state);
73 }
74 }
75
76 static int
i2c_sense_scl(void * data)77 i2c_sense_scl(void *data)
78 {
79 struct nouveau_i2c_chan *port = data;
80 struct drm_nouveau_private *dev_priv = port->dev->dev_private;
81 if (port->type == 0) {
82 return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x04);
83 } else
84 if (port->type == 4) {
85 return !!(nv_rd32(port->dev, port->sense) & 0x00040000);
86 } else
87 if (port->type == 5) {
88 if (dev_priv->card_type < NV_D0)
89 return !!(nv_rd32(port->dev, port->sense) & 0x01);
90 else
91 return !!(nv_rd32(port->dev, port->sense) & 0x10);
92 }
93 return 0;
94 }
95
96 static int
i2c_sense_sda(void * data)97 i2c_sense_sda(void *data)
98 {
99 struct nouveau_i2c_chan *port = data;
100 struct drm_nouveau_private *dev_priv = port->dev->dev_private;
101 if (port->type == 0) {
102 return !!(NVReadVgaCrtc(port->dev, 0, port->sense) & 0x08);
103 } else
104 if (port->type == 4) {
105 return !!(nv_rd32(port->dev, port->sense) & 0x00080000);
106 } else
107 if (port->type == 5) {
108 if (dev_priv->card_type < NV_D0)
109 return !!(nv_rd32(port->dev, port->sense) & 0x02);
110 else
111 return !!(nv_rd32(port->dev, port->sense) & 0x20);
112 }
113 return 0;
114 }
115
116 static void
i2c_delay(struct nouveau_i2c_chan * port,u32 nsec)117 i2c_delay(struct nouveau_i2c_chan *port, u32 nsec)
118 {
119 udelay((nsec + 500) / 1000);
120 }
121
122 static bool
i2c_raise_scl(struct nouveau_i2c_chan * port)123 i2c_raise_scl(struct nouveau_i2c_chan *port)
124 {
125 u32 timeout = T_TIMEOUT / T_RISEFALL;
126
127 i2c_drive_scl(port, 1);
128 do {
129 i2c_delay(port, T_RISEFALL);
130 } while (!i2c_sense_scl(port) && --timeout);
131
132 return timeout != 0;
133 }
134
135 static int
i2c_start(struct nouveau_i2c_chan * port)136 i2c_start(struct nouveau_i2c_chan *port)
137 {
138 int ret = 0;
139
140 port->state = i2c_sense_scl(port);
141 port->state |= i2c_sense_sda(port) << 1;
142 if (port->state != 3) {
143 i2c_drive_scl(port, 0);
144 i2c_drive_sda(port, 1);
145 if (!i2c_raise_scl(port))
146 ret = -EBUSY;
147 }
148
149 i2c_drive_sda(port, 0);
150 i2c_delay(port, T_HOLD);
151 i2c_drive_scl(port, 0);
152 i2c_delay(port, T_HOLD);
153 return ret;
154 }
155
156 static void
i2c_stop(struct nouveau_i2c_chan * port)157 i2c_stop(struct nouveau_i2c_chan *port)
158 {
159 i2c_drive_scl(port, 0);
160 i2c_drive_sda(port, 0);
161 i2c_delay(port, T_RISEFALL);
162
163 i2c_drive_scl(port, 1);
164 i2c_delay(port, T_HOLD);
165 i2c_drive_sda(port, 1);
166 i2c_delay(port, T_HOLD);
167 }
168
169 static int
i2c_bitw(struct nouveau_i2c_chan * port,int sda)170 i2c_bitw(struct nouveau_i2c_chan *port, int sda)
171 {
172 i2c_drive_sda(port, sda);
173 i2c_delay(port, T_RISEFALL);
174
175 if (!i2c_raise_scl(port))
176 return -ETIMEDOUT;
177 i2c_delay(port, T_HOLD);
178
179 i2c_drive_scl(port, 0);
180 i2c_delay(port, T_HOLD);
181 return 0;
182 }
183
184 static int
i2c_bitr(struct nouveau_i2c_chan * port)185 i2c_bitr(struct nouveau_i2c_chan *port)
186 {
187 int sda;
188
189 i2c_drive_sda(port, 1);
190 i2c_delay(port, T_RISEFALL);
191
192 if (!i2c_raise_scl(port))
193 return -ETIMEDOUT;
194 i2c_delay(port, T_HOLD);
195
196 sda = i2c_sense_sda(port);
197
198 i2c_drive_scl(port, 0);
199 i2c_delay(port, T_HOLD);
200 return sda;
201 }
202
203 static int
i2c_get_byte(struct nouveau_i2c_chan * port,u8 * byte,bool last)204 i2c_get_byte(struct nouveau_i2c_chan *port, u8 *byte, bool last)
205 {
206 int i, bit;
207
208 *byte = 0;
209 for (i = 7; i >= 0; i--) {
210 bit = i2c_bitr(port);
211 if (bit < 0)
212 return bit;
213 *byte |= bit << i;
214 }
215
216 return i2c_bitw(port, last ? 1 : 0);
217 }
218
219 static int
i2c_put_byte(struct nouveau_i2c_chan * port,u8 byte)220 i2c_put_byte(struct nouveau_i2c_chan *port, u8 byte)
221 {
222 int i, ret;
223 for (i = 7; i >= 0; i--) {
224 ret = i2c_bitw(port, !!(byte & (1 << i)));
225 if (ret < 0)
226 return ret;
227 }
228
229 ret = i2c_bitr(port);
230 if (ret == 1) /* nack */
231 ret = -EIO;
232 return ret;
233 }
234
235 static int
i2c_addr(struct nouveau_i2c_chan * port,struct i2c_msg * msg)236 i2c_addr(struct nouveau_i2c_chan *port, struct i2c_msg *msg)
237 {
238 u32 addr = msg->addr << 1;
239 if (msg->flags & I2C_M_RD)
240 addr |= 1;
241 return i2c_put_byte(port, addr);
242 }
243
244 static int
i2c_bit_xfer(struct i2c_adapter * adap,struct i2c_msg * msgs,int num)245 i2c_bit_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
246 {
247 struct nouveau_i2c_chan *port = (struct nouveau_i2c_chan *)adap;
248 struct i2c_msg *msg = msgs;
249 int ret = 0, mcnt = num;
250
251 while (!ret && mcnt--) {
252 u8 remaining = msg->len;
253 u8 *ptr = msg->buf;
254
255 ret = i2c_start(port);
256 if (ret == 0)
257 ret = i2c_addr(port, msg);
258
259 if (msg->flags & I2C_M_RD) {
260 while (!ret && remaining--)
261 ret = i2c_get_byte(port, ptr++, !remaining);
262 } else {
263 while (!ret && remaining--)
264 ret = i2c_put_byte(port, *ptr++);
265 }
266
267 msg++;
268 }
269
270 i2c_stop(port);
271 return (ret < 0) ? ret : num;
272 }
273
274 static u32
i2c_bit_func(struct i2c_adapter * adap)275 i2c_bit_func(struct i2c_adapter *adap)
276 {
277 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
278 }
279
280 const struct i2c_algorithm i2c_bit_algo = {
281 .master_xfer = i2c_bit_xfer,
282 .functionality = i2c_bit_func
283 };
284
285 static const uint32_t nv50_i2c_port[] = {
286 0x00e138, 0x00e150, 0x00e168, 0x00e180,
287 0x00e254, 0x00e274, 0x00e764, 0x00e780,
288 0x00e79c, 0x00e7b8
289 };
290
291 static u8 *
i2c_table(struct drm_device * dev,u8 * version)292 i2c_table(struct drm_device *dev, u8 *version)
293 {
294 u8 *dcb = dcb_table(dev), *i2c = NULL;
295 if (dcb) {
296 if (dcb[0] >= 0x15)
297 i2c = ROMPTR(dev, dcb[2]);
298 if (dcb[0] >= 0x30)
299 i2c = ROMPTR(dev, dcb[4]);
300 }
301
302 /* early revisions had no version number, use dcb version */
303 if (i2c) {
304 *version = dcb[0];
305 if (*version >= 0x30)
306 *version = i2c[0];
307 }
308
309 return i2c;
310 }
311
312 int
nouveau_i2c_init(struct drm_device * dev)313 nouveau_i2c_init(struct drm_device *dev)
314 {
315 struct drm_nouveau_private *dev_priv = dev->dev_private;
316 struct nvbios *bios = &dev_priv->vbios;
317 struct nouveau_i2c_chan *port;
318 u8 *i2c, *entry, legacy[2][4] = {};
319 u8 version, entries, recordlen;
320 int ret, i;
321
322 INIT_LIST_HEAD(&dev_priv->i2c_ports);
323
324 i2c = i2c_table(dev, &version);
325 if (!i2c) {
326 u8 *bmp = &bios->data[bios->offset];
327 if (bios->type != NVBIOS_BMP)
328 return -ENODEV;
329
330 legacy[0][0] = NV_CIO_CRE_DDC_WR__INDEX;
331 legacy[0][1] = NV_CIO_CRE_DDC_STATUS__INDEX;
332 legacy[1][0] = NV_CIO_CRE_DDC0_WR__INDEX;
333 legacy[1][1] = NV_CIO_CRE_DDC0_STATUS__INDEX;
334
335 /* BMP (from v4.0) has i2c info in the structure, it's in a
336 * fixed location on earlier VBIOS
337 */
338 if (bmp[5] < 4)
339 i2c = &bios->data[0x48];
340 else
341 i2c = &bmp[0x36];
342
343 if (i2c[4]) legacy[0][0] = i2c[4];
344 if (i2c[5]) legacy[0][1] = i2c[5];
345 if (i2c[6]) legacy[1][0] = i2c[6];
346 if (i2c[7]) legacy[1][1] = i2c[7];
347 }
348
349 if (i2c && version >= 0x30) {
350 entry = i2c[1] + i2c;
351 entries = i2c[2];
352 recordlen = i2c[3];
353 } else
354 if (i2c) {
355 entry = i2c;
356 entries = 16;
357 recordlen = 4;
358 } else {
359 entry = legacy[0];
360 entries = 2;
361 recordlen = 4;
362 }
363
364 for (i = 0; i < entries; i++, entry += recordlen) {
365 port = kzalloc(sizeof(*port), GFP_KERNEL);
366 if (port == NULL) {
367 nouveau_i2c_fini(dev);
368 return -ENOMEM;
369 }
370
371 port->type = entry[3];
372 if (version < 0x30) {
373 port->type &= 0x07;
374 if (port->type == 0x07)
375 port->type = 0xff;
376 }
377
378 if (port->type == 0xff) {
379 kfree(port);
380 continue;
381 }
382
383 switch (port->type) {
384 case 0: /* NV04:NV50 */
385 port->drive = entry[0];
386 port->sense = entry[1];
387 port->adapter.algo = &i2c_bit_algo;
388 break;
389 case 4: /* NV4E */
390 port->drive = 0x600800 + entry[1];
391 port->sense = port->drive;
392 port->adapter.algo = &i2c_bit_algo;
393 break;
394 case 5: /* NV50- */
395 port->drive = entry[0] & 0x0f;
396 if (dev_priv->card_type < NV_D0) {
397 if (port->drive >= ARRAY_SIZE(nv50_i2c_port))
398 break;
399 port->drive = nv50_i2c_port[port->drive];
400 port->sense = port->drive;
401 } else {
402 port->drive = 0x00d014 + (port->drive * 0x20);
403 port->sense = port->drive;
404 }
405 port->adapter.algo = &i2c_bit_algo;
406 break;
407 case 6: /* NV50- DP AUX */
408 port->drive = entry[0];
409 port->sense = port->drive;
410 port->adapter.algo = &nouveau_dp_i2c_algo;
411 break;
412 default:
413 break;
414 }
415
416 if (!port->adapter.algo) {
417 NV_ERROR(dev, "I2C%d: type %d index %x/%x unknown\n",
418 i, port->type, port->drive, port->sense);
419 kfree(port);
420 continue;
421 }
422
423 snprintf(port->adapter.name, sizeof(port->adapter.name),
424 "nouveau-%s-%d", pci_name(dev->pdev), i);
425 port->adapter.owner = THIS_MODULE;
426 port->adapter.dev.parent = &dev->pdev->dev;
427 port->dev = dev;
428 port->index = i;
429 port->dcb = ROM32(entry[0]);
430 i2c_set_adapdata(&port->adapter, i2c);
431
432 ret = i2c_add_adapter(&port->adapter);
433 if (ret) {
434 NV_ERROR(dev, "I2C%d: failed register: %d\n", i, ret);
435 kfree(port);
436 continue;
437 }
438
439 list_add_tail(&port->head, &dev_priv->i2c_ports);
440 }
441
442 return 0;
443 }
444
445 void
nouveau_i2c_fini(struct drm_device * dev)446 nouveau_i2c_fini(struct drm_device *dev)
447 {
448 struct drm_nouveau_private *dev_priv = dev->dev_private;
449 struct nouveau_i2c_chan *port, *tmp;
450
451 list_for_each_entry_safe(port, tmp, &dev_priv->i2c_ports, head) {
452 i2c_del_adapter(&port->adapter);
453 kfree(port);
454 }
455 }
456
457 struct nouveau_i2c_chan *
nouveau_i2c_find(struct drm_device * dev,u8 index)458 nouveau_i2c_find(struct drm_device *dev, u8 index)
459 {
460 struct drm_nouveau_private *dev_priv = dev->dev_private;
461 struct nouveau_i2c_chan *port;
462
463 if (index == NV_I2C_DEFAULT(0) ||
464 index == NV_I2C_DEFAULT(1)) {
465 u8 version, *i2c = i2c_table(dev, &version);
466 if (i2c && version >= 0x30) {
467 if (index == NV_I2C_DEFAULT(0))
468 index = (i2c[4] & 0x0f);
469 else
470 index = (i2c[4] & 0xf0) >> 4;
471 } else {
472 index = 2;
473 }
474 }
475
476 list_for_each_entry(port, &dev_priv->i2c_ports, head) {
477 if (port->index == index)
478 break;
479 }
480
481 if (&port->head == &dev_priv->i2c_ports)
482 return NULL;
483
484 if (dev_priv->card_type >= NV_50 && (port->dcb & 0x00000100)) {
485 u32 reg = 0x00e500, val;
486 if (port->type == 6) {
487 reg += port->drive * 0x50;
488 val = 0x2002;
489 } else {
490 reg += ((port->dcb & 0x1e00) >> 9) * 0x50;
491 val = 0xe001;
492 }
493
494 /* nfi, but neither auxch or i2c work if it's 1 */
495 nv_mask(dev, reg + 0x0c, 0x00000001, 0x00000000);
496 /* nfi, but switches auxch vs normal i2c */
497 nv_mask(dev, reg + 0x00, 0x0000f003, val);
498 }
499
500 return port;
501 }
502
503 bool
nouveau_probe_i2c_addr(struct nouveau_i2c_chan * i2c,int addr)504 nouveau_probe_i2c_addr(struct nouveau_i2c_chan *i2c, int addr)
505 {
506 uint8_t buf[] = { 0 };
507 struct i2c_msg msgs[] = {
508 {
509 .addr = addr,
510 .flags = 0,
511 .len = 1,
512 .buf = buf,
513 },
514 {
515 .addr = addr,
516 .flags = I2C_M_RD,
517 .len = 1,
518 .buf = buf,
519 }
520 };
521
522 return i2c_transfer(&i2c->adapter, msgs, 2) == 2;
523 }
524
525 int
nouveau_i2c_identify(struct drm_device * dev,const char * what,struct i2c_board_info * info,bool (* match)(struct nouveau_i2c_chan *,struct i2c_board_info *),int index)526 nouveau_i2c_identify(struct drm_device *dev, const char *what,
527 struct i2c_board_info *info,
528 bool (*match)(struct nouveau_i2c_chan *,
529 struct i2c_board_info *),
530 int index)
531 {
532 struct nouveau_i2c_chan *i2c = nouveau_i2c_find(dev, index);
533 int i;
534
535 if (!i2c) {
536 NV_DEBUG(dev, "No bus when probing %s on %d\n", what, index);
537 return -ENODEV;
538 }
539
540 NV_DEBUG(dev, "Probing %ss on I2C bus: %d\n", what, i2c->index);
541 for (i = 0; info[i].addr; i++) {
542 if (nouveau_probe_i2c_addr(i2c, info[i].addr) &&
543 (!match || match(i2c, &info[i]))) {
544 NV_INFO(dev, "Detected %s: %s\n", what, info[i].type);
545 return i;
546 }
547 }
548
549 NV_DEBUG(dev, "No devices found.\n");
550 return -ENODEV;
551 }
552