xref: /openbmc/linux/sound/soc/tegra/tegra30_ahub.c (revision ee89bd6b)
1 /*
2  * tegra30_ahub.c - Tegra30 AHUB driver
3  *
4  * Copyright (c) 2011,2012, NVIDIA CORPORATION.  All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include <linux/clk.h>
20 #include <linux/device.h>
21 #include <linux/io.h>
22 #include <linux/module.h>
23 #include <linux/of_platform.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/regmap.h>
27 #include <linux/slab.h>
28 #include <linux/clk/tegra.h>
29 #include <sound/soc.h>
30 #include "tegra30_ahub.h"
31 
32 #define DRV_NAME "tegra30-ahub"
33 
34 static struct tegra30_ahub *ahub;
35 
36 static inline void tegra30_apbif_write(u32 reg, u32 val)
37 {
38 	regmap_write(ahub->regmap_apbif, reg, val);
39 }
40 
41 static inline u32 tegra30_apbif_read(u32 reg)
42 {
43 	u32 val;
44 	regmap_read(ahub->regmap_apbif, reg, &val);
45 	return val;
46 }
47 
48 static inline void tegra30_audio_write(u32 reg, u32 val)
49 {
50 	regmap_write(ahub->regmap_ahub, reg, val);
51 }
52 
53 static int tegra30_ahub_runtime_suspend(struct device *dev)
54 {
55 	regcache_cache_only(ahub->regmap_apbif, true);
56 	regcache_cache_only(ahub->regmap_ahub, true);
57 
58 	clk_disable_unprepare(ahub->clk_apbif);
59 	clk_disable_unprepare(ahub->clk_d_audio);
60 
61 	return 0;
62 }
63 
64 /*
65  * clk_apbif isn't required for an I2S<->I2S configuration where no PCM data
66  * is read from or sent to memory. However, that's not something the rest of
67  * the driver supports right now, so we'll just treat the two clocks as one
68  * for now.
69  *
70  * These functions should not be a plain ref-count. Instead, each active stream
71  * contributes some requirement to the minimum clock rate, so starting or
72  * stopping streams should dynamically adjust the clock as required.  However,
73  * this is not yet implemented.
74  */
75 static int tegra30_ahub_runtime_resume(struct device *dev)
76 {
77 	int ret;
78 
79 	ret = clk_prepare_enable(ahub->clk_d_audio);
80 	if (ret) {
81 		dev_err(dev, "clk_enable d_audio failed: %d\n", ret);
82 		return ret;
83 	}
84 	ret = clk_prepare_enable(ahub->clk_apbif);
85 	if (ret) {
86 		dev_err(dev, "clk_enable apbif failed: %d\n", ret);
87 		clk_disable(ahub->clk_d_audio);
88 		return ret;
89 	}
90 
91 	regcache_cache_only(ahub->regmap_apbif, false);
92 	regcache_cache_only(ahub->regmap_ahub, false);
93 
94 	return 0;
95 }
96 
97 int tegra30_ahub_allocate_rx_fifo(enum tegra30_ahub_rxcif *rxcif,
98 				  dma_addr_t *fiforeg,
99 				  unsigned int *reqsel)
100 {
101 	int channel;
102 	u32 reg, val;
103 
104 	channel = find_first_zero_bit(ahub->rx_usage,
105 				      TEGRA30_AHUB_CHANNEL_CTRL_COUNT);
106 	if (channel >= TEGRA30_AHUB_CHANNEL_CTRL_COUNT)
107 		return -EBUSY;
108 
109 	__set_bit(channel, ahub->rx_usage);
110 
111 	*rxcif = TEGRA30_AHUB_RXCIF_APBIF_RX0 + channel;
112 	*fiforeg = ahub->apbif_addr + TEGRA30_AHUB_CHANNEL_RXFIFO +
113 		   (channel * TEGRA30_AHUB_CHANNEL_RXFIFO_STRIDE);
114 	*reqsel = ahub->dma_sel + channel;
115 
116 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
117 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
118 	val = tegra30_apbif_read(reg);
119 	val &= ~(TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_MASK |
120 		 TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_MASK);
121 	val |= (7 << TEGRA30_AHUB_CHANNEL_CTRL_RX_THRESHOLD_SHIFT) |
122 	       TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_EN |
123 	       TEGRA30_AHUB_CHANNEL_CTRL_RX_PACK_16;
124 	tegra30_apbif_write(reg, val);
125 
126 	reg = TEGRA30_AHUB_CIF_RX_CTRL +
127 	      (channel * TEGRA30_AHUB_CIF_RX_CTRL_STRIDE);
128 	val = (0 << TEGRA30_AUDIOCIF_CTRL_FIFO_THRESHOLD_SHIFT) |
129 	      (1 << TEGRA30_AUDIOCIF_CTRL_AUDIO_CHANNELS_SHIFT) |
130 	      (1 << TEGRA30_AUDIOCIF_CTRL_CLIENT_CHANNELS_SHIFT) |
131 	      TEGRA30_AUDIOCIF_CTRL_AUDIO_BITS_16 |
132 	      TEGRA30_AUDIOCIF_CTRL_CLIENT_BITS_16 |
133 	      TEGRA30_AUDIOCIF_CTRL_DIRECTION_RX;
134 	tegra30_apbif_write(reg, val);
135 
136 	return 0;
137 }
138 EXPORT_SYMBOL_GPL(tegra30_ahub_allocate_rx_fifo);
139 
140 int tegra30_ahub_enable_rx_fifo(enum tegra30_ahub_rxcif rxcif)
141 {
142 	int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
143 	int reg, val;
144 
145 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
146 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
147 	val = tegra30_apbif_read(reg);
148 	val |= TEGRA30_AHUB_CHANNEL_CTRL_RX_EN;
149 	tegra30_apbif_write(reg, val);
150 
151 	return 0;
152 }
153 EXPORT_SYMBOL_GPL(tegra30_ahub_enable_rx_fifo);
154 
155 int tegra30_ahub_disable_rx_fifo(enum tegra30_ahub_rxcif rxcif)
156 {
157 	int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
158 	int reg, val;
159 
160 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
161 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
162 	val = tegra30_apbif_read(reg);
163 	val &= ~TEGRA30_AHUB_CHANNEL_CTRL_RX_EN;
164 	tegra30_apbif_write(reg, val);
165 
166 	return 0;
167 }
168 EXPORT_SYMBOL_GPL(tegra30_ahub_disable_rx_fifo);
169 
170 int tegra30_ahub_free_rx_fifo(enum tegra30_ahub_rxcif rxcif)
171 {
172 	int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
173 
174 	__clear_bit(channel, ahub->rx_usage);
175 
176 	return 0;
177 }
178 EXPORT_SYMBOL_GPL(tegra30_ahub_free_rx_fifo);
179 
180 int tegra30_ahub_allocate_tx_fifo(enum tegra30_ahub_txcif *txcif,
181 				  dma_addr_t *fiforeg,
182 				  unsigned int *reqsel)
183 {
184 	int channel;
185 	u32 reg, val;
186 
187 	channel = find_first_zero_bit(ahub->tx_usage,
188 				      TEGRA30_AHUB_CHANNEL_CTRL_COUNT);
189 	if (channel >= TEGRA30_AHUB_CHANNEL_CTRL_COUNT)
190 		return -EBUSY;
191 
192 	__set_bit(channel, ahub->tx_usage);
193 
194 	*txcif = TEGRA30_AHUB_TXCIF_APBIF_TX0 + channel;
195 	*fiforeg = ahub->apbif_addr + TEGRA30_AHUB_CHANNEL_TXFIFO +
196 		   (channel * TEGRA30_AHUB_CHANNEL_TXFIFO_STRIDE);
197 	*reqsel = ahub->dma_sel + channel;
198 
199 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
200 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
201 	val = tegra30_apbif_read(reg);
202 	val &= ~(TEGRA30_AHUB_CHANNEL_CTRL_TX_THRESHOLD_MASK |
203 		 TEGRA30_AHUB_CHANNEL_CTRL_TX_PACK_MASK);
204 	val |= (7 << TEGRA30_AHUB_CHANNEL_CTRL_TX_THRESHOLD_SHIFT) |
205 	       TEGRA30_AHUB_CHANNEL_CTRL_TX_PACK_EN |
206 	       TEGRA30_AHUB_CHANNEL_CTRL_TX_PACK_16;
207 	tegra30_apbif_write(reg, val);
208 
209 	reg = TEGRA30_AHUB_CIF_TX_CTRL +
210 	      (channel * TEGRA30_AHUB_CIF_TX_CTRL_STRIDE);
211 	val = (0 << TEGRA30_AUDIOCIF_CTRL_FIFO_THRESHOLD_SHIFT) |
212 	      (1 << TEGRA30_AUDIOCIF_CTRL_AUDIO_CHANNELS_SHIFT) |
213 	      (1 << TEGRA30_AUDIOCIF_CTRL_CLIENT_CHANNELS_SHIFT) |
214 	      TEGRA30_AUDIOCIF_CTRL_AUDIO_BITS_16 |
215 	      TEGRA30_AUDIOCIF_CTRL_CLIENT_BITS_16 |
216 	      TEGRA30_AUDIOCIF_CTRL_DIRECTION_TX;
217 	tegra30_apbif_write(reg, val);
218 
219 	return 0;
220 }
221 EXPORT_SYMBOL_GPL(tegra30_ahub_allocate_tx_fifo);
222 
223 int tegra30_ahub_enable_tx_fifo(enum tegra30_ahub_txcif txcif)
224 {
225 	int channel = txcif - TEGRA30_AHUB_TXCIF_APBIF_TX0;
226 	int reg, val;
227 
228 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
229 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
230 	val = tegra30_apbif_read(reg);
231 	val |= TEGRA30_AHUB_CHANNEL_CTRL_TX_EN;
232 	tegra30_apbif_write(reg, val);
233 
234 	return 0;
235 }
236 EXPORT_SYMBOL_GPL(tegra30_ahub_enable_tx_fifo);
237 
238 int tegra30_ahub_disable_tx_fifo(enum tegra30_ahub_txcif txcif)
239 {
240 	int channel = txcif - TEGRA30_AHUB_TXCIF_APBIF_TX0;
241 	int reg, val;
242 
243 	reg = TEGRA30_AHUB_CHANNEL_CTRL +
244 	      (channel * TEGRA30_AHUB_CHANNEL_CTRL_STRIDE);
245 	val = tegra30_apbif_read(reg);
246 	val &= ~TEGRA30_AHUB_CHANNEL_CTRL_TX_EN;
247 	tegra30_apbif_write(reg, val);
248 
249 	return 0;
250 }
251 EXPORT_SYMBOL_GPL(tegra30_ahub_disable_tx_fifo);
252 
253 int tegra30_ahub_free_tx_fifo(enum tegra30_ahub_txcif txcif)
254 {
255 	int channel = txcif - TEGRA30_AHUB_TXCIF_APBIF_TX0;
256 
257 	__clear_bit(channel, ahub->tx_usage);
258 
259 	return 0;
260 }
261 EXPORT_SYMBOL_GPL(tegra30_ahub_free_tx_fifo);
262 
263 int tegra30_ahub_set_rx_cif_source(enum tegra30_ahub_rxcif rxcif,
264 				   enum tegra30_ahub_txcif txcif)
265 {
266 	int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
267 	int reg;
268 
269 	reg = TEGRA30_AHUB_AUDIO_RX +
270 	      (channel * TEGRA30_AHUB_AUDIO_RX_STRIDE);
271 	tegra30_audio_write(reg, 1 << txcif);
272 
273 	return 0;
274 }
275 EXPORT_SYMBOL_GPL(tegra30_ahub_set_rx_cif_source);
276 
277 int tegra30_ahub_unset_rx_cif_source(enum tegra30_ahub_rxcif rxcif)
278 {
279 	int channel = rxcif - TEGRA30_AHUB_RXCIF_APBIF_RX0;
280 	int reg;
281 
282 	reg = TEGRA30_AHUB_AUDIO_RX +
283 	      (channel * TEGRA30_AHUB_AUDIO_RX_STRIDE);
284 	tegra30_audio_write(reg, 0);
285 
286 	return 0;
287 }
288 EXPORT_SYMBOL_GPL(tegra30_ahub_unset_rx_cif_source);
289 
290 #define CLK_LIST_MASK_TEGRA30	BIT(0)
291 #define CLK_LIST_MASK_TEGRA114	BIT(1)
292 
293 #define CLK_LIST_MASK_TEGRA30_OR_LATER \
294 		(CLK_LIST_MASK_TEGRA30 | CLK_LIST_MASK_TEGRA114)
295 
296 static const struct {
297 	const char *clk_name;
298 	u32 clk_list_mask;
299 } configlink_clocks[] = {
300 	{ "i2s0", CLK_LIST_MASK_TEGRA30_OR_LATER },
301 	{ "i2s1", CLK_LIST_MASK_TEGRA30_OR_LATER },
302 	{ "i2s2", CLK_LIST_MASK_TEGRA30_OR_LATER },
303 	{ "i2s3", CLK_LIST_MASK_TEGRA30_OR_LATER },
304 	{ "i2s4", CLK_LIST_MASK_TEGRA30_OR_LATER },
305 	{ "dam0", CLK_LIST_MASK_TEGRA30_OR_LATER },
306 	{ "dam1", CLK_LIST_MASK_TEGRA30_OR_LATER },
307 	{ "dam2", CLK_LIST_MASK_TEGRA30_OR_LATER },
308 	{ "spdif_in", CLK_LIST_MASK_TEGRA30_OR_LATER },
309 	{ "amx", CLK_LIST_MASK_TEGRA114 },
310 	{ "adx", CLK_LIST_MASK_TEGRA114 },
311 };
312 
313 #define LAST_REG(name) \
314 	(TEGRA30_AHUB_##name + \
315 	 (TEGRA30_AHUB_##name##_STRIDE * TEGRA30_AHUB_##name##_COUNT) - 4)
316 
317 #define REG_IN_ARRAY(reg, name) \
318 	((reg >= TEGRA30_AHUB_##name) && \
319 	 (reg <= LAST_REG(name) && \
320 	 (!((reg - TEGRA30_AHUB_##name) % TEGRA30_AHUB_##name##_STRIDE))))
321 
322 static bool tegra30_ahub_apbif_wr_rd_reg(struct device *dev, unsigned int reg)
323 {
324 	switch (reg) {
325 	case TEGRA30_AHUB_CONFIG_LINK_CTRL:
326 	case TEGRA30_AHUB_MISC_CTRL:
327 	case TEGRA30_AHUB_APBDMA_LIVE_STATUS:
328 	case TEGRA30_AHUB_I2S_LIVE_STATUS:
329 	case TEGRA30_AHUB_SPDIF_LIVE_STATUS:
330 	case TEGRA30_AHUB_I2S_INT_MASK:
331 	case TEGRA30_AHUB_DAM_INT_MASK:
332 	case TEGRA30_AHUB_SPDIF_INT_MASK:
333 	case TEGRA30_AHUB_APBIF_INT_MASK:
334 	case TEGRA30_AHUB_I2S_INT_STATUS:
335 	case TEGRA30_AHUB_DAM_INT_STATUS:
336 	case TEGRA30_AHUB_SPDIF_INT_STATUS:
337 	case TEGRA30_AHUB_APBIF_INT_STATUS:
338 	case TEGRA30_AHUB_I2S_INT_SOURCE:
339 	case TEGRA30_AHUB_DAM_INT_SOURCE:
340 	case TEGRA30_AHUB_SPDIF_INT_SOURCE:
341 	case TEGRA30_AHUB_APBIF_INT_SOURCE:
342 	case TEGRA30_AHUB_I2S_INT_SET:
343 	case TEGRA30_AHUB_DAM_INT_SET:
344 	case TEGRA30_AHUB_SPDIF_INT_SET:
345 	case TEGRA30_AHUB_APBIF_INT_SET:
346 		return true;
347 	default:
348 		break;
349 	};
350 
351 	if (REG_IN_ARRAY(reg, CHANNEL_CTRL) ||
352 	    REG_IN_ARRAY(reg, CHANNEL_CLEAR) ||
353 	    REG_IN_ARRAY(reg, CHANNEL_STATUS) ||
354 	    REG_IN_ARRAY(reg, CHANNEL_TXFIFO) ||
355 	    REG_IN_ARRAY(reg, CHANNEL_RXFIFO) ||
356 	    REG_IN_ARRAY(reg, CIF_TX_CTRL) ||
357 	    REG_IN_ARRAY(reg, CIF_RX_CTRL) ||
358 	    REG_IN_ARRAY(reg, DAM_LIVE_STATUS))
359 		return true;
360 
361 	return false;
362 }
363 
364 static bool tegra30_ahub_apbif_volatile_reg(struct device *dev,
365 					    unsigned int reg)
366 {
367 	switch (reg) {
368 	case TEGRA30_AHUB_CONFIG_LINK_CTRL:
369 	case TEGRA30_AHUB_MISC_CTRL:
370 	case TEGRA30_AHUB_APBDMA_LIVE_STATUS:
371 	case TEGRA30_AHUB_I2S_LIVE_STATUS:
372 	case TEGRA30_AHUB_SPDIF_LIVE_STATUS:
373 	case TEGRA30_AHUB_I2S_INT_STATUS:
374 	case TEGRA30_AHUB_DAM_INT_STATUS:
375 	case TEGRA30_AHUB_SPDIF_INT_STATUS:
376 	case TEGRA30_AHUB_APBIF_INT_STATUS:
377 	case TEGRA30_AHUB_I2S_INT_SET:
378 	case TEGRA30_AHUB_DAM_INT_SET:
379 	case TEGRA30_AHUB_SPDIF_INT_SET:
380 	case TEGRA30_AHUB_APBIF_INT_SET:
381 		return true;
382 	default:
383 		break;
384 	};
385 
386 	if (REG_IN_ARRAY(reg, CHANNEL_CLEAR) ||
387 	    REG_IN_ARRAY(reg, CHANNEL_STATUS) ||
388 	    REG_IN_ARRAY(reg, CHANNEL_TXFIFO) ||
389 	    REG_IN_ARRAY(reg, CHANNEL_RXFIFO) ||
390 	    REG_IN_ARRAY(reg, DAM_LIVE_STATUS))
391 		return true;
392 
393 	return false;
394 }
395 
396 static bool tegra30_ahub_apbif_precious_reg(struct device *dev,
397 					    unsigned int reg)
398 {
399 	if (REG_IN_ARRAY(reg, CHANNEL_TXFIFO) ||
400 	    REG_IN_ARRAY(reg, CHANNEL_RXFIFO))
401 		return true;
402 
403 	return false;
404 }
405 
406 static const struct regmap_config tegra30_ahub_apbif_regmap_config = {
407 	.name = "apbif",
408 	.reg_bits = 32,
409 	.val_bits = 32,
410 	.reg_stride = 4,
411 	.max_register = TEGRA30_AHUB_APBIF_INT_SET,
412 	.writeable_reg = tegra30_ahub_apbif_wr_rd_reg,
413 	.readable_reg = tegra30_ahub_apbif_wr_rd_reg,
414 	.volatile_reg = tegra30_ahub_apbif_volatile_reg,
415 	.precious_reg = tegra30_ahub_apbif_precious_reg,
416 	.cache_type = REGCACHE_RBTREE,
417 };
418 
419 static bool tegra30_ahub_ahub_wr_rd_reg(struct device *dev, unsigned int reg)
420 {
421 	if (REG_IN_ARRAY(reg, AUDIO_RX))
422 		return true;
423 
424 	return false;
425 }
426 
427 static const struct regmap_config tegra30_ahub_ahub_regmap_config = {
428 	.name = "ahub",
429 	.reg_bits = 32,
430 	.val_bits = 32,
431 	.reg_stride = 4,
432 	.max_register = LAST_REG(AUDIO_RX),
433 	.writeable_reg = tegra30_ahub_ahub_wr_rd_reg,
434 	.readable_reg = tegra30_ahub_ahub_wr_rd_reg,
435 	.cache_type = REGCACHE_RBTREE,
436 };
437 
438 static struct tegra30_ahub_soc_data soc_data_tegra30 = {
439 	.clk_list_mask = CLK_LIST_MASK_TEGRA30,
440 };
441 
442 static struct tegra30_ahub_soc_data soc_data_tegra114 = {
443 	.clk_list_mask = CLK_LIST_MASK_TEGRA114,
444 };
445 
446 static const struct of_device_id tegra30_ahub_of_match[] = {
447 	{ .compatible = "nvidia,tegra114-ahub", .data = &soc_data_tegra114 },
448 	{ .compatible = "nvidia,tegra30-ahub",  .data = &soc_data_tegra30 },
449 	{},
450 };
451 
452 static int tegra30_ahub_probe(struct platform_device *pdev)
453 {
454 	const struct of_device_id *match;
455 	const struct tegra30_ahub_soc_data *soc_data;
456 	struct clk *clk;
457 	int i;
458 	struct resource *res0, *res1, *region;
459 	u32 of_dma[2];
460 	void __iomem *regs_apbif, *regs_ahub;
461 	int ret = 0;
462 
463 	if (ahub)
464 		return -ENODEV;
465 
466 	match = of_match_device(tegra30_ahub_of_match, &pdev->dev);
467 	if (!match)
468 		return -EINVAL;
469 	soc_data = match->data;
470 
471 	/*
472 	 * The AHUB hosts a register bus: the "configlink". For this to
473 	 * operate correctly, all devices on this bus must be out of reset.
474 	 * Ensure that here.
475 	 */
476 	for (i = 0; i < ARRAY_SIZE(configlink_clocks); i++) {
477 		if (!(configlink_clocks[i].clk_list_mask &
478 					soc_data->clk_list_mask))
479 			continue;
480 		clk = clk_get(&pdev->dev, configlink_clocks[i].clk_name);
481 		if (IS_ERR(clk)) {
482 			dev_err(&pdev->dev, "Can't get clock %s\n",
483 				configlink_clocks[i].clk_name);
484 			ret = PTR_ERR(clk);
485 			goto err;
486 		}
487 		tegra_periph_reset_deassert(clk);
488 		clk_put(clk);
489 	}
490 
491 	ahub = devm_kzalloc(&pdev->dev, sizeof(struct tegra30_ahub),
492 			    GFP_KERNEL);
493 	if (!ahub) {
494 		dev_err(&pdev->dev, "Can't allocate tegra30_ahub\n");
495 		ret = -ENOMEM;
496 		goto err;
497 	}
498 	dev_set_drvdata(&pdev->dev, ahub);
499 
500 	ahub->dev = &pdev->dev;
501 
502 	ahub->clk_d_audio = clk_get(&pdev->dev, "d_audio");
503 	if (IS_ERR(ahub->clk_d_audio)) {
504 		dev_err(&pdev->dev, "Can't retrieve ahub d_audio clock\n");
505 		ret = PTR_ERR(ahub->clk_d_audio);
506 		goto err;
507 	}
508 
509 	ahub->clk_apbif = clk_get(&pdev->dev, "apbif");
510 	if (IS_ERR(ahub->clk_apbif)) {
511 		dev_err(&pdev->dev, "Can't retrieve ahub apbif clock\n");
512 		ret = PTR_ERR(ahub->clk_apbif);
513 		goto err_clk_put_d_audio;
514 	}
515 
516 	if (of_property_read_u32_array(pdev->dev.of_node,
517 				"nvidia,dma-request-selector",
518 				of_dma, 2) < 0) {
519 		dev_err(&pdev->dev,
520 			"Missing property nvidia,dma-request-selector\n");
521 		ret = -ENODEV;
522 		goto err_clk_put_d_audio;
523 	}
524 	ahub->dma_sel = of_dma[1];
525 
526 	res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
527 	if (!res0) {
528 		dev_err(&pdev->dev, "No apbif memory resource\n");
529 		ret = -ENODEV;
530 		goto err_clk_put_apbif;
531 	}
532 
533 	region = devm_request_mem_region(&pdev->dev, res0->start,
534 					 resource_size(res0), DRV_NAME);
535 	if (!region) {
536 		dev_err(&pdev->dev, "request region apbif failed\n");
537 		ret = -EBUSY;
538 		goto err_clk_put_apbif;
539 	}
540 	ahub->apbif_addr = res0->start;
541 
542 	regs_apbif = devm_ioremap(&pdev->dev, res0->start,
543 				  resource_size(res0));
544 	if (!regs_apbif) {
545 		dev_err(&pdev->dev, "ioremap apbif failed\n");
546 		ret = -ENOMEM;
547 		goto err_clk_put_apbif;
548 	}
549 
550 	ahub->regmap_apbif = devm_regmap_init_mmio(&pdev->dev, regs_apbif,
551 					&tegra30_ahub_apbif_regmap_config);
552 	if (IS_ERR(ahub->regmap_apbif)) {
553 		dev_err(&pdev->dev, "apbif regmap init failed\n");
554 		ret = PTR_ERR(ahub->regmap_apbif);
555 		goto err_clk_put_apbif;
556 	}
557 	regcache_cache_only(ahub->regmap_apbif, true);
558 
559 	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
560 	if (!res1) {
561 		dev_err(&pdev->dev, "No ahub memory resource\n");
562 		ret = -ENODEV;
563 		goto err_clk_put_apbif;
564 	}
565 
566 	region = devm_request_mem_region(&pdev->dev, res1->start,
567 					 resource_size(res1), DRV_NAME);
568 	if (!region) {
569 		dev_err(&pdev->dev, "request region ahub failed\n");
570 		ret = -EBUSY;
571 		goto err_clk_put_apbif;
572 	}
573 
574 	regs_ahub = devm_ioremap(&pdev->dev, res1->start,
575 				 resource_size(res1));
576 	if (!regs_ahub) {
577 		dev_err(&pdev->dev, "ioremap ahub failed\n");
578 		ret = -ENOMEM;
579 		goto err_clk_put_apbif;
580 	}
581 
582 	ahub->regmap_ahub = devm_regmap_init_mmio(&pdev->dev, regs_ahub,
583 					&tegra30_ahub_ahub_regmap_config);
584 	if (IS_ERR(ahub->regmap_ahub)) {
585 		dev_err(&pdev->dev, "ahub regmap init failed\n");
586 		ret = PTR_ERR(ahub->regmap_ahub);
587 		goto err_clk_put_apbif;
588 	}
589 	regcache_cache_only(ahub->regmap_ahub, true);
590 
591 	pm_runtime_enable(&pdev->dev);
592 	if (!pm_runtime_enabled(&pdev->dev)) {
593 		ret = tegra30_ahub_runtime_resume(&pdev->dev);
594 		if (ret)
595 			goto err_pm_disable;
596 	}
597 
598 	of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
599 
600 	return 0;
601 
602 err_pm_disable:
603 	pm_runtime_disable(&pdev->dev);
604 err_clk_put_apbif:
605 	clk_put(ahub->clk_apbif);
606 err_clk_put_d_audio:
607 	clk_put(ahub->clk_d_audio);
608 	ahub = NULL;
609 err:
610 	return ret;
611 }
612 
613 static int tegra30_ahub_remove(struct platform_device *pdev)
614 {
615 	if (!ahub)
616 		return -ENODEV;
617 
618 	pm_runtime_disable(&pdev->dev);
619 	if (!pm_runtime_status_suspended(&pdev->dev))
620 		tegra30_ahub_runtime_suspend(&pdev->dev);
621 
622 	clk_put(ahub->clk_apbif);
623 	clk_put(ahub->clk_d_audio);
624 
625 	ahub = NULL;
626 
627 	return 0;
628 }
629 
630 static const struct dev_pm_ops tegra30_ahub_pm_ops = {
631 	SET_RUNTIME_PM_OPS(tegra30_ahub_runtime_suspend,
632 			   tegra30_ahub_runtime_resume, NULL)
633 };
634 
635 static struct platform_driver tegra30_ahub_driver = {
636 	.probe = tegra30_ahub_probe,
637 	.remove = tegra30_ahub_remove,
638 	.driver = {
639 		.name = DRV_NAME,
640 		.owner = THIS_MODULE,
641 		.of_match_table = tegra30_ahub_of_match,
642 		.pm = &tegra30_ahub_pm_ops,
643 	},
644 };
645 module_platform_driver(tegra30_ahub_driver);
646 
647 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
648 MODULE_DESCRIPTION("Tegra30 AHUB driver");
649 MODULE_LICENSE("GPL v2");
650 MODULE_ALIAS("platform:" DRV_NAME);
651 MODULE_DEVICE_TABLE(of, tegra30_ahub_of_match);
652