xref: /linux/drivers/gpu/drm/radeon/radeon_i2c.c (revision 88c90e800675b98008d5ebe5e81245910417a22d)
1 /*
2  * Copyright 2007-8 Advanced Micro Devices, Inc.
3  * Copyright 2008 Red Hat Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * Authors: Dave Airlie
24  *          Alex Deucher
25  */
26 
27 #include <linux/export.h>
28 
29 #include <drm/drm_device.h>
30 #include <drm/drm_edid.h>
31 #include <drm/drm_pci.h>
32 #include <drm/radeon_drm.h>
33 
34 #include "radeon.h"
35 #include "atom.h"
36 
37 extern int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
38 				   struct i2c_msg *msgs, int num);
39 extern u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap);
40 
41 /**
42  * radeon_ddc_probe
43  *
44  */
45 bool radeon_ddc_probe(struct radeon_connector *radeon_connector, bool use_aux)
46 {
47 	u8 out = 0x0;
48 	u8 buf[8];
49 	int ret;
50 	struct i2c_msg msgs[] = {
51 		{
52 			.addr = DDC_ADDR,
53 			.flags = 0,
54 			.len = 1,
55 			.buf = &out,
56 		},
57 		{
58 			.addr = DDC_ADDR,
59 			.flags = I2C_M_RD,
60 			.len = 8,
61 			.buf = buf,
62 		}
63 	};
64 
65 	/* on hw with routers, select right port */
66 	if (radeon_connector->router.ddc_valid)
67 		radeon_router_select_ddc_port(radeon_connector);
68 
69 	if (use_aux) {
70 		ret = i2c_transfer(&radeon_connector->ddc_bus->aux.ddc, msgs, 2);
71 	} else {
72 		ret = i2c_transfer(&radeon_connector->ddc_bus->adapter, msgs, 2);
73 	}
74 
75 	if (ret != 2)
76 		/* Couldn't find an accessible DDC on this connector */
77 		return false;
78 	/* Probe also for valid EDID header
79 	 * EDID header starts with:
80 	 * 0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00.
81 	 * Only the first 6 bytes must be valid as
82 	 * drm_edid_block_valid() can fix the last 2 bytes */
83 	if (drm_edid_header_is_valid(buf) < 6) {
84 		/* Couldn't find an accessible EDID on this
85 		 * connector */
86 		return false;
87 	}
88 	return true;
89 }
90 
91 /* bit banging i2c */
92 
93 static int pre_xfer(struct i2c_adapter *i2c_adap)
94 {
95 	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
96 	struct radeon_device *rdev = i2c->dev->dev_private;
97 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
98 	uint32_t temp;
99 
100 	mutex_lock(&i2c->mutex);
101 
102 	/* RV410 appears to have a bug where the hw i2c in reset
103 	 * holds the i2c port in a bad state - switch hw i2c away before
104 	 * doing DDC - do this for all r200s/r300s/r400s for safety sake
105 	 */
106 	if (rec->hw_capable) {
107 		if ((rdev->family >= CHIP_R200) && !ASIC_IS_AVIVO(rdev)) {
108 			u32 reg;
109 
110 			if (rdev->family >= CHIP_RV350)
111 				reg = RADEON_GPIO_MONID;
112 			else if ((rdev->family == CHIP_R300) ||
113 				 (rdev->family == CHIP_R350))
114 				reg = RADEON_GPIO_DVI_DDC;
115 			else
116 				reg = RADEON_GPIO_CRT2_DDC;
117 
118 			mutex_lock(&rdev->dc_hw_i2c_mutex);
119 			if (rec->a_clk_reg == reg) {
120 				WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
121 							       R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1)));
122 			} else {
123 				WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
124 							       R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3)));
125 			}
126 			mutex_unlock(&rdev->dc_hw_i2c_mutex);
127 		}
128 	}
129 
130 	/* switch the pads to ddc mode */
131 	if (ASIC_IS_DCE3(rdev) && rec->hw_capable) {
132 		temp = RREG32(rec->mask_clk_reg);
133 		temp &= ~(1 << 16);
134 		WREG32(rec->mask_clk_reg, temp);
135 	}
136 
137 	/* clear the output pin values */
138 	temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask;
139 	WREG32(rec->a_clk_reg, temp);
140 
141 	temp = RREG32(rec->a_data_reg) & ~rec->a_data_mask;
142 	WREG32(rec->a_data_reg, temp);
143 
144 	/* set the pins to input */
145 	temp = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
146 	WREG32(rec->en_clk_reg, temp);
147 
148 	temp = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
149 	WREG32(rec->en_data_reg, temp);
150 
151 	/* mask the gpio pins for software use */
152 	temp = RREG32(rec->mask_clk_reg) | rec->mask_clk_mask;
153 	WREG32(rec->mask_clk_reg, temp);
154 	temp = RREG32(rec->mask_clk_reg);
155 
156 	temp = RREG32(rec->mask_data_reg) | rec->mask_data_mask;
157 	WREG32(rec->mask_data_reg, temp);
158 	temp = RREG32(rec->mask_data_reg);
159 
160 	return 0;
161 }
162 
163 static void post_xfer(struct i2c_adapter *i2c_adap)
164 {
165 	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
166 	struct radeon_device *rdev = i2c->dev->dev_private;
167 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
168 	uint32_t temp;
169 
170 	/* unmask the gpio pins for software use */
171 	temp = RREG32(rec->mask_clk_reg) & ~rec->mask_clk_mask;
172 	WREG32(rec->mask_clk_reg, temp);
173 	temp = RREG32(rec->mask_clk_reg);
174 
175 	temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask;
176 	WREG32(rec->mask_data_reg, temp);
177 	temp = RREG32(rec->mask_data_reg);
178 
179 	mutex_unlock(&i2c->mutex);
180 }
181 
182 static int get_clock(void *i2c_priv)
183 {
184 	struct radeon_i2c_chan *i2c = i2c_priv;
185 	struct radeon_device *rdev = i2c->dev->dev_private;
186 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
187 	uint32_t val;
188 
189 	/* read the value off the pin */
190 	val = RREG32(rec->y_clk_reg);
191 	val &= rec->y_clk_mask;
192 
193 	return (val != 0);
194 }
195 
196 
197 static int get_data(void *i2c_priv)
198 {
199 	struct radeon_i2c_chan *i2c = i2c_priv;
200 	struct radeon_device *rdev = i2c->dev->dev_private;
201 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
202 	uint32_t val;
203 
204 	/* read the value off the pin */
205 	val = RREG32(rec->y_data_reg);
206 	val &= rec->y_data_mask;
207 
208 	return (val != 0);
209 }
210 
211 static void set_clock(void *i2c_priv, int clock)
212 {
213 	struct radeon_i2c_chan *i2c = i2c_priv;
214 	struct radeon_device *rdev = i2c->dev->dev_private;
215 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
216 	uint32_t val;
217 
218 	/* set pin direction */
219 	val = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
220 	val |= clock ? 0 : rec->en_clk_mask;
221 	WREG32(rec->en_clk_reg, val);
222 }
223 
224 static void set_data(void *i2c_priv, int data)
225 {
226 	struct radeon_i2c_chan *i2c = i2c_priv;
227 	struct radeon_device *rdev = i2c->dev->dev_private;
228 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
229 	uint32_t val;
230 
231 	/* set pin direction */
232 	val = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
233 	val |= data ? 0 : rec->en_data_mask;
234 	WREG32(rec->en_data_reg, val);
235 }
236 
237 /* hw i2c */
238 
239 static u32 radeon_get_i2c_prescale(struct radeon_device *rdev)
240 {
241 	u32 sclk = rdev->pm.current_sclk;
242 	u32 prescale = 0;
243 	u32 nm;
244 	u8 n, m, loop;
245 	int i2c_clock;
246 
247 	switch (rdev->family) {
248 	case CHIP_R100:
249 	case CHIP_RV100:
250 	case CHIP_RS100:
251 	case CHIP_RV200:
252 	case CHIP_RS200:
253 	case CHIP_R200:
254 	case CHIP_RV250:
255 	case CHIP_RS300:
256 	case CHIP_RV280:
257 	case CHIP_R300:
258 	case CHIP_R350:
259 	case CHIP_RV350:
260 		i2c_clock = 60;
261 		nm = (sclk * 10) / (i2c_clock * 4);
262 		for (loop = 1; loop < 255; loop++) {
263 			if ((nm / loop) < loop)
264 				break;
265 		}
266 		n = loop - 1;
267 		m = loop - 2;
268 		prescale = m | (n << 8);
269 		break;
270 	case CHIP_RV380:
271 	case CHIP_RS400:
272 	case CHIP_RS480:
273 	case CHIP_R420:
274 	case CHIP_R423:
275 	case CHIP_RV410:
276 		prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
277 		break;
278 	case CHIP_RS600:
279 	case CHIP_RS690:
280 	case CHIP_RS740:
281 		/* todo */
282 		break;
283 	case CHIP_RV515:
284 	case CHIP_R520:
285 	case CHIP_RV530:
286 	case CHIP_RV560:
287 	case CHIP_RV570:
288 	case CHIP_R580:
289 		i2c_clock = 50;
290 		if (rdev->family == CHIP_R520)
291 			prescale = (127 << 8) + ((sclk * 10) / (4 * 127 * i2c_clock));
292 		else
293 			prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
294 		break;
295 	case CHIP_R600:
296 	case CHIP_RV610:
297 	case CHIP_RV630:
298 	case CHIP_RV670:
299 		/* todo */
300 		break;
301 	case CHIP_RV620:
302 	case CHIP_RV635:
303 	case CHIP_RS780:
304 	case CHIP_RS880:
305 	case CHIP_RV770:
306 	case CHIP_RV730:
307 	case CHIP_RV710:
308 	case CHIP_RV740:
309 		/* todo */
310 		break;
311 	case CHIP_CEDAR:
312 	case CHIP_REDWOOD:
313 	case CHIP_JUNIPER:
314 	case CHIP_CYPRESS:
315 	case CHIP_HEMLOCK:
316 		/* todo */
317 		break;
318 	default:
319 		DRM_ERROR("i2c: unhandled radeon chip\n");
320 		break;
321 	}
322 	return prescale;
323 }
324 
325 
326 /* hw i2c engine for r1xx-4xx hardware
327  * hw can buffer up to 15 bytes
328  */
329 static int r100_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
330 			    struct i2c_msg *msgs, int num)
331 {
332 	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
333 	struct radeon_device *rdev = i2c->dev->dev_private;
334 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
335 	struct i2c_msg *p;
336 	int i, j, k, ret = num;
337 	u32 prescale;
338 	u32 i2c_cntl_0, i2c_cntl_1, i2c_data;
339 	u32 tmp, reg;
340 
341 	mutex_lock(&rdev->dc_hw_i2c_mutex);
342 	/* take the pm lock since we need a constant sclk */
343 	mutex_lock(&rdev->pm.mutex);
344 
345 	prescale = radeon_get_i2c_prescale(rdev);
346 
347 	reg = ((prescale << RADEON_I2C_PRESCALE_SHIFT) |
348 	       RADEON_I2C_DRIVE_EN |
349 	       RADEON_I2C_START |
350 	       RADEON_I2C_STOP |
351 	       RADEON_I2C_GO);
352 
353 	if (rdev->is_atom_bios) {
354 		tmp = RREG32(RADEON_BIOS_6_SCRATCH);
355 		WREG32(RADEON_BIOS_6_SCRATCH, tmp | ATOM_S6_HW_I2C_BUSY_STATE);
356 	}
357 
358 	if (rec->mm_i2c) {
359 		i2c_cntl_0 = RADEON_I2C_CNTL_0;
360 		i2c_cntl_1 = RADEON_I2C_CNTL_1;
361 		i2c_data = RADEON_I2C_DATA;
362 	} else {
363 		i2c_cntl_0 = RADEON_DVI_I2C_CNTL_0;
364 		i2c_cntl_1 = RADEON_DVI_I2C_CNTL_1;
365 		i2c_data = RADEON_DVI_I2C_DATA;
366 
367 		switch (rdev->family) {
368 		case CHIP_R100:
369 		case CHIP_RV100:
370 		case CHIP_RS100:
371 		case CHIP_RV200:
372 		case CHIP_RS200:
373 		case CHIP_RS300:
374 			switch (rec->mask_clk_reg) {
375 			case RADEON_GPIO_DVI_DDC:
376 				/* no gpio select bit */
377 				break;
378 			default:
379 				DRM_ERROR("gpio not supported with hw i2c\n");
380 				ret = -EINVAL;
381 				goto done;
382 			}
383 			break;
384 		case CHIP_R200:
385 			/* only bit 4 on r200 */
386 			switch (rec->mask_clk_reg) {
387 			case RADEON_GPIO_DVI_DDC:
388 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
389 				break;
390 			case RADEON_GPIO_MONID:
391 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
392 				break;
393 			default:
394 				DRM_ERROR("gpio not supported with hw i2c\n");
395 				ret = -EINVAL;
396 				goto done;
397 			}
398 			break;
399 		case CHIP_RV250:
400 		case CHIP_RV280:
401 			/* bits 3 and 4 */
402 			switch (rec->mask_clk_reg) {
403 			case RADEON_GPIO_DVI_DDC:
404 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
405 				break;
406 			case RADEON_GPIO_VGA_DDC:
407 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC2);
408 				break;
409 			case RADEON_GPIO_CRT2_DDC:
410 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
411 				break;
412 			default:
413 				DRM_ERROR("gpio not supported with hw i2c\n");
414 				ret = -EINVAL;
415 				goto done;
416 			}
417 			break;
418 		case CHIP_R300:
419 		case CHIP_R350:
420 			/* only bit 4 on r300/r350 */
421 			switch (rec->mask_clk_reg) {
422 			case RADEON_GPIO_VGA_DDC:
423 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
424 				break;
425 			case RADEON_GPIO_DVI_DDC:
426 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
427 				break;
428 			default:
429 				DRM_ERROR("gpio not supported with hw i2c\n");
430 				ret = -EINVAL;
431 				goto done;
432 			}
433 			break;
434 		case CHIP_RV350:
435 		case CHIP_RV380:
436 		case CHIP_R420:
437 		case CHIP_R423:
438 		case CHIP_RV410:
439 		case CHIP_RS400:
440 		case CHIP_RS480:
441 			/* bits 3 and 4 */
442 			switch (rec->mask_clk_reg) {
443 			case RADEON_GPIO_VGA_DDC:
444 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
445 				break;
446 			case RADEON_GPIO_DVI_DDC:
447 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC2);
448 				break;
449 			case RADEON_GPIO_MONID:
450 				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
451 				break;
452 			default:
453 				DRM_ERROR("gpio not supported with hw i2c\n");
454 				ret = -EINVAL;
455 				goto done;
456 			}
457 			break;
458 		default:
459 			DRM_ERROR("unsupported asic\n");
460 			ret = -EINVAL;
461 			goto done;
462 			break;
463 		}
464 	}
465 
466 	/* check for bus probe */
467 	p = &msgs[0];
468 	if ((num == 1) && (p->len == 0)) {
469 		WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
470 				    RADEON_I2C_NACK |
471 				    RADEON_I2C_HALT |
472 				    RADEON_I2C_SOFT_RST));
473 		WREG32(i2c_data, (p->addr << 1) & 0xff);
474 		WREG32(i2c_data, 0);
475 		WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
476 				    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
477 				    RADEON_I2C_EN |
478 				    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
479 		WREG32(i2c_cntl_0, reg);
480 		for (k = 0; k < 32; k++) {
481 			udelay(10);
482 			tmp = RREG32(i2c_cntl_0);
483 			if (tmp & RADEON_I2C_GO)
484 				continue;
485 			tmp = RREG32(i2c_cntl_0);
486 			if (tmp & RADEON_I2C_DONE)
487 				break;
488 			else {
489 				DRM_DEBUG("i2c write error 0x%08x\n", tmp);
490 				WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
491 				ret = -EIO;
492 				goto done;
493 			}
494 		}
495 		goto done;
496 	}
497 
498 	for (i = 0; i < num; i++) {
499 		p = &msgs[i];
500 		for (j = 0; j < p->len; j++) {
501 			if (p->flags & I2C_M_RD) {
502 				WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
503 						    RADEON_I2C_NACK |
504 						    RADEON_I2C_HALT |
505 						    RADEON_I2C_SOFT_RST));
506 				WREG32(i2c_data, ((p->addr << 1) & 0xff) | 0x1);
507 				WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
508 						    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
509 						    RADEON_I2C_EN |
510 						    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
511 				WREG32(i2c_cntl_0, reg | RADEON_I2C_RECEIVE);
512 				for (k = 0; k < 32; k++) {
513 					udelay(10);
514 					tmp = RREG32(i2c_cntl_0);
515 					if (tmp & RADEON_I2C_GO)
516 						continue;
517 					tmp = RREG32(i2c_cntl_0);
518 					if (tmp & RADEON_I2C_DONE)
519 						break;
520 					else {
521 						DRM_DEBUG("i2c read error 0x%08x\n", tmp);
522 						WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
523 						ret = -EIO;
524 						goto done;
525 					}
526 				}
527 				p->buf[j] = RREG32(i2c_data) & 0xff;
528 			} else {
529 				WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
530 						    RADEON_I2C_NACK |
531 						    RADEON_I2C_HALT |
532 						    RADEON_I2C_SOFT_RST));
533 				WREG32(i2c_data, (p->addr << 1) & 0xff);
534 				WREG32(i2c_data, p->buf[j]);
535 				WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
536 						    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
537 						    RADEON_I2C_EN |
538 						    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
539 				WREG32(i2c_cntl_0, reg);
540 				for (k = 0; k < 32; k++) {
541 					udelay(10);
542 					tmp = RREG32(i2c_cntl_0);
543 					if (tmp & RADEON_I2C_GO)
544 						continue;
545 					tmp = RREG32(i2c_cntl_0);
546 					if (tmp & RADEON_I2C_DONE)
547 						break;
548 					else {
549 						DRM_DEBUG("i2c write error 0x%08x\n", tmp);
550 						WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
551 						ret = -EIO;
552 						goto done;
553 					}
554 				}
555 			}
556 		}
557 	}
558 
559 done:
560 	WREG32(i2c_cntl_0, 0);
561 	WREG32(i2c_cntl_1, 0);
562 	WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
563 			    RADEON_I2C_NACK |
564 			    RADEON_I2C_HALT |
565 			    RADEON_I2C_SOFT_RST));
566 
567 	if (rdev->is_atom_bios) {
568 		tmp = RREG32(RADEON_BIOS_6_SCRATCH);
569 		tmp &= ~ATOM_S6_HW_I2C_BUSY_STATE;
570 		WREG32(RADEON_BIOS_6_SCRATCH, tmp);
571 	}
572 
573 	mutex_unlock(&rdev->pm.mutex);
574 	mutex_unlock(&rdev->dc_hw_i2c_mutex);
575 
576 	return ret;
577 }
578 
579 /* hw i2c engine for r5xx hardware
580  * hw can buffer up to 15 bytes
581  */
582 static int r500_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
583 			    struct i2c_msg *msgs, int num)
584 {
585 	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
586 	struct radeon_device *rdev = i2c->dev->dev_private;
587 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
588 	struct i2c_msg *p;
589 	int i, j, remaining, current_count, buffer_offset, ret = num;
590 	u32 prescale;
591 	u32 tmp, reg;
592 	u32 saved1, saved2;
593 
594 	mutex_lock(&rdev->dc_hw_i2c_mutex);
595 	/* take the pm lock since we need a constant sclk */
596 	mutex_lock(&rdev->pm.mutex);
597 
598 	prescale = radeon_get_i2c_prescale(rdev);
599 
600 	/* clear gpio mask bits */
601 	tmp = RREG32(rec->mask_clk_reg);
602 	tmp &= ~rec->mask_clk_mask;
603 	WREG32(rec->mask_clk_reg, tmp);
604 	tmp = RREG32(rec->mask_clk_reg);
605 
606 	tmp = RREG32(rec->mask_data_reg);
607 	tmp &= ~rec->mask_data_mask;
608 	WREG32(rec->mask_data_reg, tmp);
609 	tmp = RREG32(rec->mask_data_reg);
610 
611 	/* clear pin values */
612 	tmp = RREG32(rec->a_clk_reg);
613 	tmp &= ~rec->a_clk_mask;
614 	WREG32(rec->a_clk_reg, tmp);
615 	tmp = RREG32(rec->a_clk_reg);
616 
617 	tmp = RREG32(rec->a_data_reg);
618 	tmp &= ~rec->a_data_mask;
619 	WREG32(rec->a_data_reg, tmp);
620 	tmp = RREG32(rec->a_data_reg);
621 
622 	/* set the pins to input */
623 	tmp = RREG32(rec->en_clk_reg);
624 	tmp &= ~rec->en_clk_mask;
625 	WREG32(rec->en_clk_reg, tmp);
626 	tmp = RREG32(rec->en_clk_reg);
627 
628 	tmp = RREG32(rec->en_data_reg);
629 	tmp &= ~rec->en_data_mask;
630 	WREG32(rec->en_data_reg, tmp);
631 	tmp = RREG32(rec->en_data_reg);
632 
633 	/* */
634 	tmp = RREG32(RADEON_BIOS_6_SCRATCH);
635 	WREG32(RADEON_BIOS_6_SCRATCH, tmp | ATOM_S6_HW_I2C_BUSY_STATE);
636 	saved1 = RREG32(AVIVO_DC_I2C_CONTROL1);
637 	saved2 = RREG32(0x494);
638 	WREG32(0x494, saved2 | 0x1);
639 
640 	WREG32(AVIVO_DC_I2C_ARBITRATION, AVIVO_DC_I2C_SW_WANTS_TO_USE_I2C);
641 	for (i = 0; i < 50; i++) {
642 		udelay(1);
643 		if (RREG32(AVIVO_DC_I2C_ARBITRATION) & AVIVO_DC_I2C_SW_CAN_USE_I2C)
644 			break;
645 	}
646 	if (i == 50) {
647 		DRM_ERROR("failed to get i2c bus\n");
648 		ret = -EBUSY;
649 		goto done;
650 	}
651 
652 	reg = AVIVO_DC_I2C_START | AVIVO_DC_I2C_STOP | AVIVO_DC_I2C_EN;
653 	switch (rec->mask_clk_reg) {
654 	case AVIVO_DC_GPIO_DDC1_MASK:
655 		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC1);
656 		break;
657 	case AVIVO_DC_GPIO_DDC2_MASK:
658 		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC2);
659 		break;
660 	case AVIVO_DC_GPIO_DDC3_MASK:
661 		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC3);
662 		break;
663 	default:
664 		DRM_ERROR("gpio not supported with hw i2c\n");
665 		ret = -EINVAL;
666 		goto done;
667 	}
668 
669 	/* check for bus probe */
670 	p = &msgs[0];
671 	if ((num == 1) && (p->len == 0)) {
672 		WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
673 					      AVIVO_DC_I2C_NACK |
674 					      AVIVO_DC_I2C_HALT));
675 		WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
676 		udelay(1);
677 		WREG32(AVIVO_DC_I2C_RESET, 0);
678 
679 		WREG32(AVIVO_DC_I2C_DATA, (p->addr << 1) & 0xff);
680 		WREG32(AVIVO_DC_I2C_DATA, 0);
681 
682 		WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
683 		WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
684 					       AVIVO_DC_I2C_DATA_COUNT(1) |
685 					       (prescale << 16)));
686 		WREG32(AVIVO_DC_I2C_CONTROL1, reg);
687 		WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
688 		for (j = 0; j < 200; j++) {
689 			udelay(50);
690 			tmp = RREG32(AVIVO_DC_I2C_STATUS1);
691 			if (tmp & AVIVO_DC_I2C_GO)
692 				continue;
693 			tmp = RREG32(AVIVO_DC_I2C_STATUS1);
694 			if (tmp & AVIVO_DC_I2C_DONE)
695 				break;
696 			else {
697 				DRM_DEBUG("i2c write error 0x%08x\n", tmp);
698 				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
699 				ret = -EIO;
700 				goto done;
701 			}
702 		}
703 		goto done;
704 	}
705 
706 	for (i = 0; i < num; i++) {
707 		p = &msgs[i];
708 		remaining = p->len;
709 		buffer_offset = 0;
710 		if (p->flags & I2C_M_RD) {
711 			while (remaining) {
712 				if (remaining > 15)
713 					current_count = 15;
714 				else
715 					current_count = remaining;
716 				WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
717 							      AVIVO_DC_I2C_NACK |
718 							      AVIVO_DC_I2C_HALT));
719 				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
720 				udelay(1);
721 				WREG32(AVIVO_DC_I2C_RESET, 0);
722 
723 				WREG32(AVIVO_DC_I2C_DATA, ((p->addr << 1) & 0xff) | 0x1);
724 				WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
725 				WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
726 							       AVIVO_DC_I2C_DATA_COUNT(current_count) |
727 							       (prescale << 16)));
728 				WREG32(AVIVO_DC_I2C_CONTROL1, reg | AVIVO_DC_I2C_RECEIVE);
729 				WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
730 				for (j = 0; j < 200; j++) {
731 					udelay(50);
732 					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
733 					if (tmp & AVIVO_DC_I2C_GO)
734 						continue;
735 					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
736 					if (tmp & AVIVO_DC_I2C_DONE)
737 						break;
738 					else {
739 						DRM_DEBUG("i2c read error 0x%08x\n", tmp);
740 						WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
741 						ret = -EIO;
742 						goto done;
743 					}
744 				}
745 				for (j = 0; j < current_count; j++)
746 					p->buf[buffer_offset + j] = RREG32(AVIVO_DC_I2C_DATA) & 0xff;
747 				remaining -= current_count;
748 				buffer_offset += current_count;
749 			}
750 		} else {
751 			while (remaining) {
752 				if (remaining > 15)
753 					current_count = 15;
754 				else
755 					current_count = remaining;
756 				WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
757 							      AVIVO_DC_I2C_NACK |
758 							      AVIVO_DC_I2C_HALT));
759 				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
760 				udelay(1);
761 				WREG32(AVIVO_DC_I2C_RESET, 0);
762 
763 				WREG32(AVIVO_DC_I2C_DATA, (p->addr << 1) & 0xff);
764 				for (j = 0; j < current_count; j++)
765 					WREG32(AVIVO_DC_I2C_DATA, p->buf[buffer_offset + j]);
766 
767 				WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
768 				WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
769 							       AVIVO_DC_I2C_DATA_COUNT(current_count) |
770 							       (prescale << 16)));
771 				WREG32(AVIVO_DC_I2C_CONTROL1, reg);
772 				WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
773 				for (j = 0; j < 200; j++) {
774 					udelay(50);
775 					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
776 					if (tmp & AVIVO_DC_I2C_GO)
777 						continue;
778 					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
779 					if (tmp & AVIVO_DC_I2C_DONE)
780 						break;
781 					else {
782 						DRM_DEBUG("i2c write error 0x%08x\n", tmp);
783 						WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
784 						ret = -EIO;
785 						goto done;
786 					}
787 				}
788 				remaining -= current_count;
789 				buffer_offset += current_count;
790 			}
791 		}
792 	}
793 
794 done:
795 	WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
796 				      AVIVO_DC_I2C_NACK |
797 				      AVIVO_DC_I2C_HALT));
798 	WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
799 	udelay(1);
800 	WREG32(AVIVO_DC_I2C_RESET, 0);
801 
802 	WREG32(AVIVO_DC_I2C_ARBITRATION, AVIVO_DC_I2C_SW_DONE_USING_I2C);
803 	WREG32(AVIVO_DC_I2C_CONTROL1, saved1);
804 	WREG32(0x494, saved2);
805 	tmp = RREG32(RADEON_BIOS_6_SCRATCH);
806 	tmp &= ~ATOM_S6_HW_I2C_BUSY_STATE;
807 	WREG32(RADEON_BIOS_6_SCRATCH, tmp);
808 
809 	mutex_unlock(&rdev->pm.mutex);
810 	mutex_unlock(&rdev->dc_hw_i2c_mutex);
811 
812 	return ret;
813 }
814 
815 static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
816 			      struct i2c_msg *msgs, int num)
817 {
818 	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
819 	struct radeon_device *rdev = i2c->dev->dev_private;
820 	struct radeon_i2c_bus_rec *rec = &i2c->rec;
821 	int ret = 0;
822 
823 	mutex_lock(&i2c->mutex);
824 
825 	switch (rdev->family) {
826 	case CHIP_R100:
827 	case CHIP_RV100:
828 	case CHIP_RS100:
829 	case CHIP_RV200:
830 	case CHIP_RS200:
831 	case CHIP_R200:
832 	case CHIP_RV250:
833 	case CHIP_RS300:
834 	case CHIP_RV280:
835 	case CHIP_R300:
836 	case CHIP_R350:
837 	case CHIP_RV350:
838 	case CHIP_RV380:
839 	case CHIP_R420:
840 	case CHIP_R423:
841 	case CHIP_RV410:
842 	case CHIP_RS400:
843 	case CHIP_RS480:
844 		ret = r100_hw_i2c_xfer(i2c_adap, msgs, num);
845 		break;
846 	case CHIP_RS600:
847 	case CHIP_RS690:
848 	case CHIP_RS740:
849 		/* XXX fill in hw i2c implementation */
850 		break;
851 	case CHIP_RV515:
852 	case CHIP_R520:
853 	case CHIP_RV530:
854 	case CHIP_RV560:
855 	case CHIP_RV570:
856 	case CHIP_R580:
857 		if (rec->mm_i2c)
858 			ret = r100_hw_i2c_xfer(i2c_adap, msgs, num);
859 		else
860 			ret = r500_hw_i2c_xfer(i2c_adap, msgs, num);
861 		break;
862 	case CHIP_R600:
863 	case CHIP_RV610:
864 	case CHIP_RV630:
865 	case CHIP_RV670:
866 		/* XXX fill in hw i2c implementation */
867 		break;
868 	case CHIP_RV620:
869 	case CHIP_RV635:
870 	case CHIP_RS780:
871 	case CHIP_RS880:
872 	case CHIP_RV770:
873 	case CHIP_RV730:
874 	case CHIP_RV710:
875 	case CHIP_RV740:
876 		/* XXX fill in hw i2c implementation */
877 		break;
878 	case CHIP_CEDAR:
879 	case CHIP_REDWOOD:
880 	case CHIP_JUNIPER:
881 	case CHIP_CYPRESS:
882 	case CHIP_HEMLOCK:
883 		/* XXX fill in hw i2c implementation */
884 		break;
885 	default:
886 		DRM_ERROR("i2c: unhandled radeon chip\n");
887 		ret = -EIO;
888 		break;
889 	}
890 
891 	mutex_unlock(&i2c->mutex);
892 
893 	return ret;
894 }
895 
896 static u32 radeon_hw_i2c_func(struct i2c_adapter *adap)
897 {
898 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
899 }
900 
901 static const struct i2c_algorithm radeon_i2c_algo = {
902 	.master_xfer = radeon_hw_i2c_xfer,
903 	.functionality = radeon_hw_i2c_func,
904 };
905 
906 static const struct i2c_algorithm radeon_atom_i2c_algo = {
907 	.master_xfer = radeon_atom_hw_i2c_xfer,
908 	.functionality = radeon_atom_hw_i2c_func,
909 };
910 
911 struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev,
912 					  struct radeon_i2c_bus_rec *rec,
913 					  const char *name)
914 {
915 	struct radeon_device *rdev = dev->dev_private;
916 	struct radeon_i2c_chan *i2c;
917 	int ret;
918 
919 	/* don't add the mm_i2c bus unless hw_i2c is enabled */
920 	if (rec->mm_i2c && (radeon_hw_i2c == 0))
921 		return NULL;
922 
923 	i2c = kzalloc(sizeof(struct radeon_i2c_chan), GFP_KERNEL);
924 	if (i2c == NULL)
925 		return NULL;
926 
927 	i2c->rec = *rec;
928 	i2c->adapter.owner = THIS_MODULE;
929 	i2c->adapter.class = I2C_CLASS_DDC;
930 	i2c->adapter.dev.parent = &dev->pdev->dev;
931 	i2c->dev = dev;
932 	i2c_set_adapdata(&i2c->adapter, i2c);
933 	mutex_init(&i2c->mutex);
934 	if (rec->mm_i2c ||
935 	    (rec->hw_capable &&
936 	     radeon_hw_i2c &&
937 	     ((rdev->family <= CHIP_RS480) ||
938 	      ((rdev->family >= CHIP_RV515) && (rdev->family <= CHIP_R580))))) {
939 		/* set the radeon hw i2c adapter */
940 		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
941 			 "Radeon i2c hw bus %s", name);
942 		i2c->adapter.algo = &radeon_i2c_algo;
943 		ret = i2c_add_adapter(&i2c->adapter);
944 		if (ret)
945 			goto out_free;
946 	} else if (rec->hw_capable &&
947 		   radeon_hw_i2c &&
948 		   ASIC_IS_DCE3(rdev)) {
949 		/* hw i2c using atom */
950 		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
951 			 "Radeon i2c hw bus %s", name);
952 		i2c->adapter.algo = &radeon_atom_i2c_algo;
953 		ret = i2c_add_adapter(&i2c->adapter);
954 		if (ret)
955 			goto out_free;
956 	} else {
957 		/* set the radeon bit adapter */
958 		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
959 			 "Radeon i2c bit bus %s", name);
960 		i2c->adapter.algo_data = &i2c->bit;
961 		i2c->bit.pre_xfer = pre_xfer;
962 		i2c->bit.post_xfer = post_xfer;
963 		i2c->bit.setsda = set_data;
964 		i2c->bit.setscl = set_clock;
965 		i2c->bit.getsda = get_data;
966 		i2c->bit.getscl = get_clock;
967 		i2c->bit.udelay = 10;
968 		i2c->bit.timeout = usecs_to_jiffies(2200);	/* from VESA */
969 		i2c->bit.data = i2c;
970 		ret = i2c_bit_add_bus(&i2c->adapter);
971 		if (ret) {
972 			DRM_ERROR("Failed to register bit i2c %s\n", name);
973 			goto out_free;
974 		}
975 	}
976 
977 	return i2c;
978 out_free:
979 	kfree(i2c);
980 	return NULL;
981 
982 }
983 
984 void radeon_i2c_destroy(struct radeon_i2c_chan *i2c)
985 {
986 	if (!i2c)
987 		return;
988 	WARN_ON(i2c->has_aux);
989 	i2c_del_adapter(&i2c->adapter);
990 	kfree(i2c);
991 }
992 
993 /* Add the default buses */
994 void radeon_i2c_init(struct radeon_device *rdev)
995 {
996 	if (radeon_hw_i2c)
997 		DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");
998 
999 	if (rdev->is_atom_bios)
1000 		radeon_atombios_i2c_init(rdev);
1001 	else
1002 		radeon_combios_i2c_init(rdev);
1003 }
1004 
1005 /* remove all the buses */
1006 void radeon_i2c_fini(struct radeon_device *rdev)
1007 {
1008 	int i;
1009 
1010 	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
1011 		if (rdev->i2c_bus[i]) {
1012 			radeon_i2c_destroy(rdev->i2c_bus[i]);
1013 			rdev->i2c_bus[i] = NULL;
1014 		}
1015 	}
1016 }
1017 
1018 /* Add additional buses */
1019 void radeon_i2c_add(struct radeon_device *rdev,
1020 		    struct radeon_i2c_bus_rec *rec,
1021 		    const char *name)
1022 {
1023 	struct drm_device *dev = rdev->ddev;
1024 	int i;
1025 
1026 	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
1027 		if (!rdev->i2c_bus[i]) {
1028 			rdev->i2c_bus[i] = radeon_i2c_create(dev, rec, name);
1029 			return;
1030 		}
1031 	}
1032 }
1033 
1034 /* looks up bus based on id */
1035 struct radeon_i2c_chan *radeon_i2c_lookup(struct radeon_device *rdev,
1036 					  struct radeon_i2c_bus_rec *i2c_bus)
1037 {
1038 	int i;
1039 
1040 	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
1041 		if (rdev->i2c_bus[i] &&
1042 		    (rdev->i2c_bus[i]->rec.i2c_id == i2c_bus->i2c_id)) {
1043 			return rdev->i2c_bus[i];
1044 		}
1045 	}
1046 	return NULL;
1047 }
1048 
1049 void radeon_i2c_get_byte(struct radeon_i2c_chan *i2c_bus,
1050 			 u8 slave_addr,
1051 			 u8 addr,
1052 			 u8 *val)
1053 {
1054 	u8 out_buf[2];
1055 	u8 in_buf[2];
1056 	struct i2c_msg msgs[] = {
1057 		{
1058 			.addr = slave_addr,
1059 			.flags = 0,
1060 			.len = 1,
1061 			.buf = out_buf,
1062 		},
1063 		{
1064 			.addr = slave_addr,
1065 			.flags = I2C_M_RD,
1066 			.len = 1,
1067 			.buf = in_buf,
1068 		}
1069 	};
1070 
1071 	out_buf[0] = addr;
1072 	out_buf[1] = 0;
1073 
1074 	if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) {
1075 		*val = in_buf[0];
1076 		DRM_DEBUG("val = 0x%02x\n", *val);
1077 	} else {
1078 		DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n",
1079 			  addr, *val);
1080 	}
1081 }
1082 
1083 void radeon_i2c_put_byte(struct radeon_i2c_chan *i2c_bus,
1084 			 u8 slave_addr,
1085 			 u8 addr,
1086 			 u8 val)
1087 {
1088 	uint8_t out_buf[2];
1089 	struct i2c_msg msg = {
1090 		.addr = slave_addr,
1091 		.flags = 0,
1092 		.len = 2,
1093 		.buf = out_buf,
1094 	};
1095 
1096 	out_buf[0] = addr;
1097 	out_buf[1] = val;
1098 
1099 	if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1)
1100 		DRM_DEBUG("i2c 0x%02x 0x%02x write failed\n",
1101 			  addr, val);
1102 }
1103 
1104 /* ddc router switching */
1105 void radeon_router_select_ddc_port(struct radeon_connector *radeon_connector)
1106 {
1107 	u8 val;
1108 
1109 	if (!radeon_connector->router.ddc_valid)
1110 		return;
1111 
1112 	if (!radeon_connector->router_bus)
1113 		return;
1114 
1115 	radeon_i2c_get_byte(radeon_connector->router_bus,
1116 			    radeon_connector->router.i2c_addr,
1117 			    0x3, &val);
1118 	val &= ~radeon_connector->router.ddc_mux_control_pin;
1119 	radeon_i2c_put_byte(radeon_connector->router_bus,
1120 			    radeon_connector->router.i2c_addr,
1121 			    0x3, val);
1122 	radeon_i2c_get_byte(radeon_connector->router_bus,
1123 			    radeon_connector->router.i2c_addr,
1124 			    0x1, &val);
1125 	val &= ~radeon_connector->router.ddc_mux_control_pin;
1126 	val |= radeon_connector->router.ddc_mux_state;
1127 	radeon_i2c_put_byte(radeon_connector->router_bus,
1128 			    radeon_connector->router.i2c_addr,
1129 			    0x1, val);
1130 }
1131 
1132 /* clock/data router switching */
1133 void radeon_router_select_cd_port(struct radeon_connector *radeon_connector)
1134 {
1135 	u8 val;
1136 
1137 	if (!radeon_connector->router.cd_valid)
1138 		return;
1139 
1140 	if (!radeon_connector->router_bus)
1141 		return;
1142 
1143 	radeon_i2c_get_byte(radeon_connector->router_bus,
1144 			    radeon_connector->router.i2c_addr,
1145 			    0x3, &val);
1146 	val &= ~radeon_connector->router.cd_mux_control_pin;
1147 	radeon_i2c_put_byte(radeon_connector->router_bus,
1148 			    radeon_connector->router.i2c_addr,
1149 			    0x3, val);
1150 	radeon_i2c_get_byte(radeon_connector->router_bus,
1151 			    radeon_connector->router.i2c_addr,
1152 			    0x1, &val);
1153 	val &= ~radeon_connector->router.cd_mux_control_pin;
1154 	val |= radeon_connector->router.cd_mux_state;
1155 	radeon_i2c_put_byte(radeon_connector->router_bus,
1156 			    radeon_connector->router.i2c_addr,
1157 			    0x1, val);
1158 }
1159 
1160