xref: /openbmc/linux/drivers/crypto/mxs-dcp.c (revision df687341)
1 /*
2  * Freescale i.MX23/i.MX28 Data Co-Processor driver
3  *
4  * Copyright (C) 2013 Marek Vasut <marex@denx.de>
5  *
6  * The code contained herein is licensed under the GNU General Public
7  * License. You may obtain a copy of the GNU General Public License
8  * Version 2 or later at the following locations:
9  *
10  * http://www.opensource.org/licenses/gpl-license.html
11  * http://www.gnu.org/copyleft/gpl.html
12  */
13 
14 #include <linux/dma-mapping.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/kernel.h>
18 #include <linux/kthread.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/stmp_device.h>
23 #include <linux/clk.h>
24 
25 #include <crypto/aes.h>
26 #include <crypto/sha.h>
27 #include <crypto/internal/hash.h>
28 #include <crypto/internal/skcipher.h>
29 
30 #define DCP_MAX_CHANS	4
31 #define DCP_BUF_SZ	PAGE_SIZE
32 #define DCP_SHA_PAY_SZ  64
33 
34 #define DCP_ALIGNMENT	64
35 
36 /*
37  * Null hashes to align with hw behavior on imx6sl and ull
38  * these are flipped for consistency with hw output
39  */
40 static const uint8_t sha1_null_hash[] =
41 	"\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
42 	"\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
43 
44 static const uint8_t sha256_null_hash[] =
45 	"\x55\xb8\x52\x78\x1b\x99\x95\xa4"
46 	"\x4c\x93\x9b\x64\xe4\x41\xae\x27"
47 	"\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
48 	"\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
49 
50 /* DCP DMA descriptor. */
51 struct dcp_dma_desc {
52 	uint32_t	next_cmd_addr;
53 	uint32_t	control0;
54 	uint32_t	control1;
55 	uint32_t	source;
56 	uint32_t	destination;
57 	uint32_t	size;
58 	uint32_t	payload;
59 	uint32_t	status;
60 };
61 
62 /* Coherent aligned block for bounce buffering. */
63 struct dcp_coherent_block {
64 	uint8_t			aes_in_buf[DCP_BUF_SZ];
65 	uint8_t			aes_out_buf[DCP_BUF_SZ];
66 	uint8_t			sha_in_buf[DCP_BUF_SZ];
67 	uint8_t			sha_out_buf[DCP_SHA_PAY_SZ];
68 
69 	uint8_t			aes_key[2 * AES_KEYSIZE_128];
70 
71 	struct dcp_dma_desc	desc[DCP_MAX_CHANS];
72 };
73 
74 struct dcp {
75 	struct device			*dev;
76 	void __iomem			*base;
77 
78 	uint32_t			caps;
79 
80 	struct dcp_coherent_block	*coh;
81 
82 	struct completion		completion[DCP_MAX_CHANS];
83 	spinlock_t			lock[DCP_MAX_CHANS];
84 	struct task_struct		*thread[DCP_MAX_CHANS];
85 	struct crypto_queue		queue[DCP_MAX_CHANS];
86 	struct clk			*dcp_clk;
87 };
88 
89 enum dcp_chan {
90 	DCP_CHAN_HASH_SHA	= 0,
91 	DCP_CHAN_CRYPTO		= 2,
92 };
93 
94 struct dcp_async_ctx {
95 	/* Common context */
96 	enum dcp_chan	chan;
97 	uint32_t	fill;
98 
99 	/* SHA Hash-specific context */
100 	struct mutex			mutex;
101 	uint32_t			alg;
102 	unsigned int			hot:1;
103 
104 	/* Crypto-specific context */
105 	struct crypto_sync_skcipher	*fallback;
106 	unsigned int			key_len;
107 	uint8_t				key[AES_KEYSIZE_128];
108 };
109 
110 struct dcp_aes_req_ctx {
111 	unsigned int	enc:1;
112 	unsigned int	ecb:1;
113 };
114 
115 struct dcp_sha_req_ctx {
116 	unsigned int	init:1;
117 	unsigned int	fini:1;
118 };
119 
120 struct dcp_export_state {
121 	struct dcp_sha_req_ctx req_ctx;
122 	struct dcp_async_ctx async_ctx;
123 };
124 
125 /*
126  * There can even be only one instance of the MXS DCP due to the
127  * design of Linux Crypto API.
128  */
129 static struct dcp *global_sdcp;
130 
131 /* DCP register layout. */
132 #define MXS_DCP_CTRL				0x00
133 #define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES	(1 << 23)
134 #define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING	(1 << 22)
135 
136 #define MXS_DCP_STAT				0x10
137 #define MXS_DCP_STAT_CLR			0x18
138 #define MXS_DCP_STAT_IRQ_MASK			0xf
139 
140 #define MXS_DCP_CHANNELCTRL			0x20
141 #define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK	0xff
142 
143 #define MXS_DCP_CAPABILITY1			0x40
144 #define MXS_DCP_CAPABILITY1_SHA256		(4 << 16)
145 #define MXS_DCP_CAPABILITY1_SHA1		(1 << 16)
146 #define MXS_DCP_CAPABILITY1_AES128		(1 << 0)
147 
148 #define MXS_DCP_CONTEXT				0x50
149 
150 #define MXS_DCP_CH_N_CMDPTR(n)			(0x100 + ((n) * 0x40))
151 
152 #define MXS_DCP_CH_N_SEMA(n)			(0x110 + ((n) * 0x40))
153 
154 #define MXS_DCP_CH_N_STAT(n)			(0x120 + ((n) * 0x40))
155 #define MXS_DCP_CH_N_STAT_CLR(n)		(0x128 + ((n) * 0x40))
156 
157 /* DMA descriptor bits. */
158 #define MXS_DCP_CONTROL0_HASH_TERM		(1 << 13)
159 #define MXS_DCP_CONTROL0_HASH_INIT		(1 << 12)
160 #define MXS_DCP_CONTROL0_PAYLOAD_KEY		(1 << 11)
161 #define MXS_DCP_CONTROL0_CIPHER_ENCRYPT		(1 << 8)
162 #define MXS_DCP_CONTROL0_CIPHER_INIT		(1 << 9)
163 #define MXS_DCP_CONTROL0_ENABLE_HASH		(1 << 6)
164 #define MXS_DCP_CONTROL0_ENABLE_CIPHER		(1 << 5)
165 #define MXS_DCP_CONTROL0_DECR_SEMAPHORE		(1 << 1)
166 #define MXS_DCP_CONTROL0_INTERRUPT		(1 << 0)
167 
168 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA256	(2 << 16)
169 #define MXS_DCP_CONTROL1_HASH_SELECT_SHA1	(0 << 16)
170 #define MXS_DCP_CONTROL1_CIPHER_MODE_CBC	(1 << 4)
171 #define MXS_DCP_CONTROL1_CIPHER_MODE_ECB	(0 << 4)
172 #define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128	(0 << 0)
173 
174 static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
175 {
176 	struct dcp *sdcp = global_sdcp;
177 	const int chan = actx->chan;
178 	uint32_t stat;
179 	unsigned long ret;
180 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
181 
182 	dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
183 					      DMA_TO_DEVICE);
184 
185 	reinit_completion(&sdcp->completion[chan]);
186 
187 	/* Clear status register. */
188 	writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
189 
190 	/* Load the DMA descriptor. */
191 	writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
192 
193 	/* Increment the semaphore to start the DMA transfer. */
194 	writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
195 
196 	ret = wait_for_completion_timeout(&sdcp->completion[chan],
197 					  msecs_to_jiffies(1000));
198 	if (!ret) {
199 		dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
200 			chan, readl(sdcp->base + MXS_DCP_STAT));
201 		return -ETIMEDOUT;
202 	}
203 
204 	stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
205 	if (stat & 0xff) {
206 		dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
207 			chan, stat);
208 		return -EINVAL;
209 	}
210 
211 	dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
212 
213 	return 0;
214 }
215 
216 /*
217  * Encryption (AES128)
218  */
219 static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
220 			   struct ablkcipher_request *req, int init)
221 {
222 	struct dcp *sdcp = global_sdcp;
223 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
224 	struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
225 	int ret;
226 
227 	dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
228 					     2 * AES_KEYSIZE_128,
229 					     DMA_TO_DEVICE);
230 	dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
231 					     DCP_BUF_SZ, DMA_TO_DEVICE);
232 	dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
233 					     DCP_BUF_SZ, DMA_FROM_DEVICE);
234 
235 	if (actx->fill % AES_BLOCK_SIZE) {
236 		dev_err(sdcp->dev, "Invalid block size!\n");
237 		ret = -EINVAL;
238 		goto aes_done_run;
239 	}
240 
241 	/* Fill in the DMA descriptor. */
242 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
243 		    MXS_DCP_CONTROL0_INTERRUPT |
244 		    MXS_DCP_CONTROL0_ENABLE_CIPHER;
245 
246 	/* Payload contains the key. */
247 	desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
248 
249 	if (rctx->enc)
250 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
251 	if (init)
252 		desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
253 
254 	desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
255 
256 	if (rctx->ecb)
257 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
258 	else
259 		desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
260 
261 	desc->next_cmd_addr = 0;
262 	desc->source = src_phys;
263 	desc->destination = dst_phys;
264 	desc->size = actx->fill;
265 	desc->payload = key_phys;
266 	desc->status = 0;
267 
268 	ret = mxs_dcp_start_dma(actx);
269 
270 aes_done_run:
271 	dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
272 			 DMA_TO_DEVICE);
273 	dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
274 	dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
275 
276 	return ret;
277 }
278 
279 static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
280 {
281 	struct dcp *sdcp = global_sdcp;
282 
283 	struct ablkcipher_request *req = ablkcipher_request_cast(arq);
284 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
285 	struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
286 
287 	struct scatterlist *dst = req->dst;
288 	struct scatterlist *src = req->src;
289 	const int nents = sg_nents(req->src);
290 
291 	const int out_off = DCP_BUF_SZ;
292 	uint8_t *in_buf = sdcp->coh->aes_in_buf;
293 	uint8_t *out_buf = sdcp->coh->aes_out_buf;
294 
295 	uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
296 	uint32_t dst_off = 0;
297 	uint32_t last_out_len = 0;
298 
299 	uint8_t *key = sdcp->coh->aes_key;
300 
301 	int ret = 0;
302 	int split = 0;
303 	unsigned int i, len, clen, rem = 0, tlen = 0;
304 	int init = 0;
305 	bool limit_hit = false;
306 
307 	actx->fill = 0;
308 
309 	/* Copy the key from the temporary location. */
310 	memcpy(key, actx->key, actx->key_len);
311 
312 	if (!rctx->ecb) {
313 		/* Copy the CBC IV just past the key. */
314 		memcpy(key + AES_KEYSIZE_128, req->info, AES_KEYSIZE_128);
315 		/* CBC needs the INIT set. */
316 		init = 1;
317 	} else {
318 		memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
319 	}
320 
321 	for_each_sg(req->src, src, nents, i) {
322 		src_buf = sg_virt(src);
323 		len = sg_dma_len(src);
324 		tlen += len;
325 		limit_hit = tlen > req->nbytes;
326 
327 		if (limit_hit)
328 			len = req->nbytes - (tlen - len);
329 
330 		do {
331 			if (actx->fill + len > out_off)
332 				clen = out_off - actx->fill;
333 			else
334 				clen = len;
335 
336 			memcpy(in_buf + actx->fill, src_buf, clen);
337 			len -= clen;
338 			src_buf += clen;
339 			actx->fill += clen;
340 
341 			/*
342 			 * If we filled the buffer or this is the last SG,
343 			 * submit the buffer.
344 			 */
345 			if (actx->fill == out_off || sg_is_last(src) ||
346 				limit_hit) {
347 				ret = mxs_dcp_run_aes(actx, req, init);
348 				if (ret)
349 					return ret;
350 				init = 0;
351 
352 				out_tmp = out_buf;
353 				last_out_len = actx->fill;
354 				while (dst && actx->fill) {
355 					if (!split) {
356 						dst_buf = sg_virt(dst);
357 						dst_off = 0;
358 					}
359 					rem = min(sg_dma_len(dst) - dst_off,
360 						  actx->fill);
361 
362 					memcpy(dst_buf + dst_off, out_tmp, rem);
363 					out_tmp += rem;
364 					dst_off += rem;
365 					actx->fill -= rem;
366 
367 					if (dst_off == sg_dma_len(dst)) {
368 						dst = sg_next(dst);
369 						split = 0;
370 					} else {
371 						split = 1;
372 					}
373 				}
374 			}
375 		} while (len);
376 
377 		if (limit_hit)
378 			break;
379 	}
380 
381 	/* Copy the IV for CBC for chaining */
382 	if (!rctx->ecb) {
383 		if (rctx->enc)
384 			memcpy(req->info, out_buf+(last_out_len-AES_BLOCK_SIZE),
385 				AES_BLOCK_SIZE);
386 		else
387 			memcpy(req->info, in_buf+(last_out_len-AES_BLOCK_SIZE),
388 				AES_BLOCK_SIZE);
389 	}
390 
391 	return ret;
392 }
393 
394 static int dcp_chan_thread_aes(void *data)
395 {
396 	struct dcp *sdcp = global_sdcp;
397 	const int chan = DCP_CHAN_CRYPTO;
398 
399 	struct crypto_async_request *backlog;
400 	struct crypto_async_request *arq;
401 
402 	int ret;
403 
404 	while (!kthread_should_stop()) {
405 		set_current_state(TASK_INTERRUPTIBLE);
406 
407 		spin_lock(&sdcp->lock[chan]);
408 		backlog = crypto_get_backlog(&sdcp->queue[chan]);
409 		arq = crypto_dequeue_request(&sdcp->queue[chan]);
410 		spin_unlock(&sdcp->lock[chan]);
411 
412 		if (!backlog && !arq) {
413 			schedule();
414 			continue;
415 		}
416 
417 		set_current_state(TASK_RUNNING);
418 
419 		if (backlog)
420 			backlog->complete(backlog, -EINPROGRESS);
421 
422 		if (arq) {
423 			ret = mxs_dcp_aes_block_crypt(arq);
424 			arq->complete(arq, ret);
425 		}
426 	}
427 
428 	return 0;
429 }
430 
431 static int mxs_dcp_block_fallback(struct ablkcipher_request *req, int enc)
432 {
433 	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
434 	struct dcp_async_ctx *ctx = crypto_ablkcipher_ctx(tfm);
435 	SYNC_SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback);
436 	int ret;
437 
438 	skcipher_request_set_sync_tfm(subreq, ctx->fallback);
439 	skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL);
440 	skcipher_request_set_crypt(subreq, req->src, req->dst,
441 				   req->nbytes, req->info);
442 
443 	if (enc)
444 		ret = crypto_skcipher_encrypt(subreq);
445 	else
446 		ret = crypto_skcipher_decrypt(subreq);
447 
448 	skcipher_request_zero(subreq);
449 
450 	return ret;
451 }
452 
453 static int mxs_dcp_aes_enqueue(struct ablkcipher_request *req, int enc, int ecb)
454 {
455 	struct dcp *sdcp = global_sdcp;
456 	struct crypto_async_request *arq = &req->base;
457 	struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
458 	struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
459 	int ret;
460 
461 	if (unlikely(actx->key_len != AES_KEYSIZE_128))
462 		return mxs_dcp_block_fallback(req, enc);
463 
464 	rctx->enc = enc;
465 	rctx->ecb = ecb;
466 	actx->chan = DCP_CHAN_CRYPTO;
467 
468 	spin_lock(&sdcp->lock[actx->chan]);
469 	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
470 	spin_unlock(&sdcp->lock[actx->chan]);
471 
472 	wake_up_process(sdcp->thread[actx->chan]);
473 
474 	return -EINPROGRESS;
475 }
476 
477 static int mxs_dcp_aes_ecb_decrypt(struct ablkcipher_request *req)
478 {
479 	return mxs_dcp_aes_enqueue(req, 0, 1);
480 }
481 
482 static int mxs_dcp_aes_ecb_encrypt(struct ablkcipher_request *req)
483 {
484 	return mxs_dcp_aes_enqueue(req, 1, 1);
485 }
486 
487 static int mxs_dcp_aes_cbc_decrypt(struct ablkcipher_request *req)
488 {
489 	return mxs_dcp_aes_enqueue(req, 0, 0);
490 }
491 
492 static int mxs_dcp_aes_cbc_encrypt(struct ablkcipher_request *req)
493 {
494 	return mxs_dcp_aes_enqueue(req, 1, 0);
495 }
496 
497 static int mxs_dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
498 			      unsigned int len)
499 {
500 	struct dcp_async_ctx *actx = crypto_ablkcipher_ctx(tfm);
501 	unsigned int ret;
502 
503 	/*
504 	 * AES 128 is supposed by the hardware, store key into temporary
505 	 * buffer and exit. We must use the temporary buffer here, since
506 	 * there can still be an operation in progress.
507 	 */
508 	actx->key_len = len;
509 	if (len == AES_KEYSIZE_128) {
510 		memcpy(actx->key, key, len);
511 		return 0;
512 	}
513 
514 	/*
515 	 * If the requested AES key size is not supported by the hardware,
516 	 * but is supported by in-kernel software implementation, we use
517 	 * software fallback.
518 	 */
519 	crypto_sync_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
520 	crypto_sync_skcipher_set_flags(actx->fallback,
521 				  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
522 
523 	ret = crypto_sync_skcipher_setkey(actx->fallback, key, len);
524 	if (!ret)
525 		return 0;
526 
527 	tfm->base.crt_flags &= ~CRYPTO_TFM_RES_MASK;
528 	tfm->base.crt_flags |= crypto_sync_skcipher_get_flags(actx->fallback) &
529 			       CRYPTO_TFM_RES_MASK;
530 
531 	return ret;
532 }
533 
534 static int mxs_dcp_aes_fallback_init(struct crypto_tfm *tfm)
535 {
536 	const char *name = crypto_tfm_alg_name(tfm);
537 	struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
538 	struct crypto_sync_skcipher *blk;
539 
540 	blk = crypto_alloc_sync_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
541 	if (IS_ERR(blk))
542 		return PTR_ERR(blk);
543 
544 	actx->fallback = blk;
545 	tfm->crt_ablkcipher.reqsize = sizeof(struct dcp_aes_req_ctx);
546 	return 0;
547 }
548 
549 static void mxs_dcp_aes_fallback_exit(struct crypto_tfm *tfm)
550 {
551 	struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
552 
553 	crypto_free_sync_skcipher(actx->fallback);
554 }
555 
556 /*
557  * Hashing (SHA1/SHA256)
558  */
559 static int mxs_dcp_run_sha(struct ahash_request *req)
560 {
561 	struct dcp *sdcp = global_sdcp;
562 	int ret;
563 
564 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
565 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
566 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
567 	struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
568 
569 	dma_addr_t digest_phys = 0;
570 	dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
571 					     DCP_BUF_SZ, DMA_TO_DEVICE);
572 
573 	/* Fill in the DMA descriptor. */
574 	desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
575 		    MXS_DCP_CONTROL0_INTERRUPT |
576 		    MXS_DCP_CONTROL0_ENABLE_HASH;
577 	if (rctx->init)
578 		desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
579 
580 	desc->control1 = actx->alg;
581 	desc->next_cmd_addr = 0;
582 	desc->source = buf_phys;
583 	desc->destination = 0;
584 	desc->size = actx->fill;
585 	desc->payload = 0;
586 	desc->status = 0;
587 
588 	/*
589 	 * Align driver with hw behavior when generating null hashes
590 	 */
591 	if (rctx->init && rctx->fini && desc->size == 0) {
592 		struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
593 		const uint8_t *sha_buf =
594 			(actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
595 			sha1_null_hash : sha256_null_hash;
596 		memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
597 		ret = 0;
598 		goto done_run;
599 	}
600 
601 	/* Set HASH_TERM bit for last transfer block. */
602 	if (rctx->fini) {
603 		digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
604 					     DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
605 		desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
606 		desc->payload = digest_phys;
607 	}
608 
609 	ret = mxs_dcp_start_dma(actx);
610 
611 	if (rctx->fini)
612 		dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
613 				 DMA_FROM_DEVICE);
614 
615 done_run:
616 	dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
617 
618 	return ret;
619 }
620 
621 static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
622 {
623 	struct dcp *sdcp = global_sdcp;
624 
625 	struct ahash_request *req = ahash_request_cast(arq);
626 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
627 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
628 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
629 	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
630 	const int nents = sg_nents(req->src);
631 
632 	uint8_t *in_buf = sdcp->coh->sha_in_buf;
633 	uint8_t *out_buf = sdcp->coh->sha_out_buf;
634 
635 	uint8_t *src_buf;
636 
637 	struct scatterlist *src;
638 
639 	unsigned int i, len, clen;
640 	int ret;
641 
642 	int fin = rctx->fini;
643 	if (fin)
644 		rctx->fini = 0;
645 
646 	for_each_sg(req->src, src, nents, i) {
647 		src_buf = sg_virt(src);
648 		len = sg_dma_len(src);
649 
650 		do {
651 			if (actx->fill + len > DCP_BUF_SZ)
652 				clen = DCP_BUF_SZ - actx->fill;
653 			else
654 				clen = len;
655 
656 			memcpy(in_buf + actx->fill, src_buf, clen);
657 			len -= clen;
658 			src_buf += clen;
659 			actx->fill += clen;
660 
661 			/*
662 			 * If we filled the buffer and still have some
663 			 * more data, submit the buffer.
664 			 */
665 			if (len && actx->fill == DCP_BUF_SZ) {
666 				ret = mxs_dcp_run_sha(req);
667 				if (ret)
668 					return ret;
669 				actx->fill = 0;
670 				rctx->init = 0;
671 			}
672 		} while (len);
673 	}
674 
675 	if (fin) {
676 		rctx->fini = 1;
677 
678 		/* Submit whatever is left. */
679 		if (!req->result)
680 			return -EINVAL;
681 
682 		ret = mxs_dcp_run_sha(req);
683 		if (ret)
684 			return ret;
685 
686 		actx->fill = 0;
687 
688 		/* For some reason the result is flipped */
689 		for (i = 0; i < halg->digestsize; i++)
690 			req->result[i] = out_buf[halg->digestsize - i - 1];
691 	}
692 
693 	return 0;
694 }
695 
696 static int dcp_chan_thread_sha(void *data)
697 {
698 	struct dcp *sdcp = global_sdcp;
699 	const int chan = DCP_CHAN_HASH_SHA;
700 
701 	struct crypto_async_request *backlog;
702 	struct crypto_async_request *arq;
703 
704 	struct dcp_sha_req_ctx *rctx;
705 
706 	struct ahash_request *req;
707 	int ret, fini;
708 
709 	while (!kthread_should_stop()) {
710 		set_current_state(TASK_INTERRUPTIBLE);
711 
712 		spin_lock(&sdcp->lock[chan]);
713 		backlog = crypto_get_backlog(&sdcp->queue[chan]);
714 		arq = crypto_dequeue_request(&sdcp->queue[chan]);
715 		spin_unlock(&sdcp->lock[chan]);
716 
717 		if (!backlog && !arq) {
718 			schedule();
719 			continue;
720 		}
721 
722 		set_current_state(TASK_RUNNING);
723 
724 		if (backlog)
725 			backlog->complete(backlog, -EINPROGRESS);
726 
727 		if (arq) {
728 			req = ahash_request_cast(arq);
729 			rctx = ahash_request_ctx(req);
730 
731 			ret = dcp_sha_req_to_buf(arq);
732 			fini = rctx->fini;
733 			arq->complete(arq, ret);
734 		}
735 	}
736 
737 	return 0;
738 }
739 
740 static int dcp_sha_init(struct ahash_request *req)
741 {
742 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
743 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
744 
745 	struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
746 
747 	/*
748 	 * Start hashing session. The code below only inits the
749 	 * hashing session context, nothing more.
750 	 */
751 	memset(actx, 0, sizeof(*actx));
752 
753 	if (strcmp(halg->base.cra_name, "sha1") == 0)
754 		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
755 	else
756 		actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
757 
758 	actx->fill = 0;
759 	actx->hot = 0;
760 	actx->chan = DCP_CHAN_HASH_SHA;
761 
762 	mutex_init(&actx->mutex);
763 
764 	return 0;
765 }
766 
767 static int dcp_sha_update_fx(struct ahash_request *req, int fini)
768 {
769 	struct dcp *sdcp = global_sdcp;
770 
771 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
772 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
773 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
774 
775 	int ret;
776 
777 	/*
778 	 * Ignore requests that have no data in them and are not
779 	 * the trailing requests in the stream of requests.
780 	 */
781 	if (!req->nbytes && !fini)
782 		return 0;
783 
784 	mutex_lock(&actx->mutex);
785 
786 	rctx->fini = fini;
787 
788 	if (!actx->hot) {
789 		actx->hot = 1;
790 		rctx->init = 1;
791 	}
792 
793 	spin_lock(&sdcp->lock[actx->chan]);
794 	ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
795 	spin_unlock(&sdcp->lock[actx->chan]);
796 
797 	wake_up_process(sdcp->thread[actx->chan]);
798 	mutex_unlock(&actx->mutex);
799 
800 	return -EINPROGRESS;
801 }
802 
803 static int dcp_sha_update(struct ahash_request *req)
804 {
805 	return dcp_sha_update_fx(req, 0);
806 }
807 
808 static int dcp_sha_final(struct ahash_request *req)
809 {
810 	ahash_request_set_crypt(req, NULL, req->result, 0);
811 	req->nbytes = 0;
812 	return dcp_sha_update_fx(req, 1);
813 }
814 
815 static int dcp_sha_finup(struct ahash_request *req)
816 {
817 	return dcp_sha_update_fx(req, 1);
818 }
819 
820 static int dcp_sha_digest(struct ahash_request *req)
821 {
822 	int ret;
823 
824 	ret = dcp_sha_init(req);
825 	if (ret)
826 		return ret;
827 
828 	return dcp_sha_finup(req);
829 }
830 
831 static int dcp_sha_import(struct ahash_request *req, const void *in)
832 {
833 	struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
834 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
835 	struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
836 	const struct dcp_export_state *export = in;
837 
838 	memset(rctx, 0, sizeof(struct dcp_sha_req_ctx));
839 	memset(actx, 0, sizeof(struct dcp_async_ctx));
840 	memcpy(rctx, &export->req_ctx, sizeof(struct dcp_sha_req_ctx));
841 	memcpy(actx, &export->async_ctx, sizeof(struct dcp_async_ctx));
842 
843 	return 0;
844 }
845 
846 static int dcp_sha_export(struct ahash_request *req, void *out)
847 {
848 	struct dcp_sha_req_ctx *rctx_state = ahash_request_ctx(req);
849 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
850 	struct dcp_async_ctx *actx_state = crypto_ahash_ctx(tfm);
851 	struct dcp_export_state *export = out;
852 
853 	memcpy(&export->req_ctx, rctx_state, sizeof(struct dcp_sha_req_ctx));
854 	memcpy(&export->async_ctx, actx_state, sizeof(struct dcp_async_ctx));
855 
856 	return 0;
857 }
858 
859 static int dcp_sha_cra_init(struct crypto_tfm *tfm)
860 {
861 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
862 				 sizeof(struct dcp_sha_req_ctx));
863 	return 0;
864 }
865 
866 static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
867 {
868 }
869 
870 /* AES 128 ECB and AES 128 CBC */
871 static struct crypto_alg dcp_aes_algs[] = {
872 	{
873 		.cra_name		= "ecb(aes)",
874 		.cra_driver_name	= "ecb-aes-dcp",
875 		.cra_priority		= 400,
876 		.cra_alignmask		= 15,
877 		.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
878 					  CRYPTO_ALG_ASYNC |
879 					  CRYPTO_ALG_NEED_FALLBACK,
880 		.cra_init		= mxs_dcp_aes_fallback_init,
881 		.cra_exit		= mxs_dcp_aes_fallback_exit,
882 		.cra_blocksize		= AES_BLOCK_SIZE,
883 		.cra_ctxsize		= sizeof(struct dcp_async_ctx),
884 		.cra_type		= &crypto_ablkcipher_type,
885 		.cra_module		= THIS_MODULE,
886 		.cra_u	= {
887 			.ablkcipher = {
888 				.min_keysize	= AES_MIN_KEY_SIZE,
889 				.max_keysize	= AES_MAX_KEY_SIZE,
890 				.setkey		= mxs_dcp_aes_setkey,
891 				.encrypt	= mxs_dcp_aes_ecb_encrypt,
892 				.decrypt	= mxs_dcp_aes_ecb_decrypt
893 			},
894 		},
895 	}, {
896 		.cra_name		= "cbc(aes)",
897 		.cra_driver_name	= "cbc-aes-dcp",
898 		.cra_priority		= 400,
899 		.cra_alignmask		= 15,
900 		.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
901 					  CRYPTO_ALG_ASYNC |
902 					  CRYPTO_ALG_NEED_FALLBACK,
903 		.cra_init		= mxs_dcp_aes_fallback_init,
904 		.cra_exit		= mxs_dcp_aes_fallback_exit,
905 		.cra_blocksize		= AES_BLOCK_SIZE,
906 		.cra_ctxsize		= sizeof(struct dcp_async_ctx),
907 		.cra_type		= &crypto_ablkcipher_type,
908 		.cra_module		= THIS_MODULE,
909 		.cra_u = {
910 			.ablkcipher = {
911 				.min_keysize	= AES_MIN_KEY_SIZE,
912 				.max_keysize	= AES_MAX_KEY_SIZE,
913 				.setkey		= mxs_dcp_aes_setkey,
914 				.encrypt	= mxs_dcp_aes_cbc_encrypt,
915 				.decrypt	= mxs_dcp_aes_cbc_decrypt,
916 				.ivsize		= AES_BLOCK_SIZE,
917 			},
918 		},
919 	},
920 };
921 
922 /* SHA1 */
923 static struct ahash_alg dcp_sha1_alg = {
924 	.init	= dcp_sha_init,
925 	.update	= dcp_sha_update,
926 	.final	= dcp_sha_final,
927 	.finup	= dcp_sha_finup,
928 	.digest	= dcp_sha_digest,
929 	.import = dcp_sha_import,
930 	.export = dcp_sha_export,
931 	.halg	= {
932 		.digestsize	= SHA1_DIGEST_SIZE,
933 		.statesize	= sizeof(struct dcp_export_state),
934 		.base		= {
935 			.cra_name		= "sha1",
936 			.cra_driver_name	= "sha1-dcp",
937 			.cra_priority		= 400,
938 			.cra_alignmask		= 63,
939 			.cra_flags		= CRYPTO_ALG_ASYNC,
940 			.cra_blocksize		= SHA1_BLOCK_SIZE,
941 			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
942 			.cra_module		= THIS_MODULE,
943 			.cra_init		= dcp_sha_cra_init,
944 			.cra_exit		= dcp_sha_cra_exit,
945 		},
946 	},
947 };
948 
949 /* SHA256 */
950 static struct ahash_alg dcp_sha256_alg = {
951 	.init	= dcp_sha_init,
952 	.update	= dcp_sha_update,
953 	.final	= dcp_sha_final,
954 	.finup	= dcp_sha_finup,
955 	.digest	= dcp_sha_digest,
956 	.import = dcp_sha_import,
957 	.export = dcp_sha_export,
958 	.halg	= {
959 		.digestsize	= SHA256_DIGEST_SIZE,
960 		.statesize	= sizeof(struct dcp_export_state),
961 		.base		= {
962 			.cra_name		= "sha256",
963 			.cra_driver_name	= "sha256-dcp",
964 			.cra_priority		= 400,
965 			.cra_alignmask		= 63,
966 			.cra_flags		= CRYPTO_ALG_ASYNC,
967 			.cra_blocksize		= SHA256_BLOCK_SIZE,
968 			.cra_ctxsize		= sizeof(struct dcp_async_ctx),
969 			.cra_module		= THIS_MODULE,
970 			.cra_init		= dcp_sha_cra_init,
971 			.cra_exit		= dcp_sha_cra_exit,
972 		},
973 	},
974 };
975 
976 static irqreturn_t mxs_dcp_irq(int irq, void *context)
977 {
978 	struct dcp *sdcp = context;
979 	uint32_t stat;
980 	int i;
981 
982 	stat = readl(sdcp->base + MXS_DCP_STAT);
983 	stat &= MXS_DCP_STAT_IRQ_MASK;
984 	if (!stat)
985 		return IRQ_NONE;
986 
987 	/* Clear the interrupts. */
988 	writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
989 
990 	/* Complete the DMA requests that finished. */
991 	for (i = 0; i < DCP_MAX_CHANS; i++)
992 		if (stat & (1 << i))
993 			complete(&sdcp->completion[i]);
994 
995 	return IRQ_HANDLED;
996 }
997 
998 static int mxs_dcp_probe(struct platform_device *pdev)
999 {
1000 	struct device *dev = &pdev->dev;
1001 	struct dcp *sdcp = NULL;
1002 	int i, ret;
1003 
1004 	struct resource *iores;
1005 	int dcp_vmi_irq, dcp_irq;
1006 
1007 	if (global_sdcp) {
1008 		dev_err(dev, "Only one DCP instance allowed!\n");
1009 		return -ENODEV;
1010 	}
1011 
1012 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1013 	dcp_vmi_irq = platform_get_irq(pdev, 0);
1014 	if (dcp_vmi_irq < 0) {
1015 		dev_err(dev, "Failed to get IRQ: (%d)!\n", dcp_vmi_irq);
1016 		return dcp_vmi_irq;
1017 	}
1018 
1019 	dcp_irq = platform_get_irq(pdev, 1);
1020 	if (dcp_irq < 0) {
1021 		dev_err(dev, "Failed to get IRQ: (%d)!\n", dcp_irq);
1022 		return dcp_irq;
1023 	}
1024 
1025 	sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
1026 	if (!sdcp)
1027 		return -ENOMEM;
1028 
1029 	sdcp->dev = dev;
1030 	sdcp->base = devm_ioremap_resource(dev, iores);
1031 	if (IS_ERR(sdcp->base))
1032 		return PTR_ERR(sdcp->base);
1033 
1034 
1035 	ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
1036 			       "dcp-vmi-irq", sdcp);
1037 	if (ret) {
1038 		dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
1039 		return ret;
1040 	}
1041 
1042 	ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
1043 			       "dcp-irq", sdcp);
1044 	if (ret) {
1045 		dev_err(dev, "Failed to claim DCP IRQ!\n");
1046 		return ret;
1047 	}
1048 
1049 	/* Allocate coherent helper block. */
1050 	sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
1051 				   GFP_KERNEL);
1052 	if (!sdcp->coh)
1053 		return -ENOMEM;
1054 
1055 	/* Re-align the structure so it fits the DCP constraints. */
1056 	sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
1057 
1058 	/* DCP clock is optional, only used on some SOCs */
1059 	sdcp->dcp_clk = devm_clk_get(dev, "dcp");
1060 	if (IS_ERR(sdcp->dcp_clk)) {
1061 		if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
1062 			return PTR_ERR(sdcp->dcp_clk);
1063 		sdcp->dcp_clk = NULL;
1064 	}
1065 	ret = clk_prepare_enable(sdcp->dcp_clk);
1066 	if (ret)
1067 		return ret;
1068 
1069 	/* Restart the DCP block. */
1070 	ret = stmp_reset_block(sdcp->base);
1071 	if (ret) {
1072 		dev_err(dev, "Failed reset\n");
1073 		goto err_disable_unprepare_clk;
1074 	}
1075 
1076 	/* Initialize control register. */
1077 	writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
1078 	       MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
1079 	       sdcp->base + MXS_DCP_CTRL);
1080 
1081 	/* Enable all DCP DMA channels. */
1082 	writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
1083 	       sdcp->base + MXS_DCP_CHANNELCTRL);
1084 
1085 	/*
1086 	 * We do not enable context switching. Give the context buffer a
1087 	 * pointer to an illegal address so if context switching is
1088 	 * inadvertantly enabled, the DCP will return an error instead of
1089 	 * trashing good memory. The DCP DMA cannot access ROM, so any ROM
1090 	 * address will do.
1091 	 */
1092 	writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
1093 	for (i = 0; i < DCP_MAX_CHANS; i++)
1094 		writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
1095 	writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
1096 
1097 	global_sdcp = sdcp;
1098 
1099 	platform_set_drvdata(pdev, sdcp);
1100 
1101 	for (i = 0; i < DCP_MAX_CHANS; i++) {
1102 		spin_lock_init(&sdcp->lock[i]);
1103 		init_completion(&sdcp->completion[i]);
1104 		crypto_init_queue(&sdcp->queue[i], 50);
1105 	}
1106 
1107 	/* Create the SHA and AES handler threads. */
1108 	sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
1109 						      NULL, "mxs_dcp_chan/sha");
1110 	if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
1111 		dev_err(dev, "Error starting SHA thread!\n");
1112 		ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
1113 		goto err_disable_unprepare_clk;
1114 	}
1115 
1116 	sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
1117 						    NULL, "mxs_dcp_chan/aes");
1118 	if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
1119 		dev_err(dev, "Error starting SHA thread!\n");
1120 		ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
1121 		goto err_destroy_sha_thread;
1122 	}
1123 
1124 	/* Register the various crypto algorithms. */
1125 	sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
1126 
1127 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
1128 		ret = crypto_register_algs(dcp_aes_algs,
1129 					   ARRAY_SIZE(dcp_aes_algs));
1130 		if (ret) {
1131 			/* Failed to register algorithm. */
1132 			dev_err(dev, "Failed to register AES crypto!\n");
1133 			goto err_destroy_aes_thread;
1134 		}
1135 	}
1136 
1137 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
1138 		ret = crypto_register_ahash(&dcp_sha1_alg);
1139 		if (ret) {
1140 			dev_err(dev, "Failed to register %s hash!\n",
1141 				dcp_sha1_alg.halg.base.cra_name);
1142 			goto err_unregister_aes;
1143 		}
1144 	}
1145 
1146 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
1147 		ret = crypto_register_ahash(&dcp_sha256_alg);
1148 		if (ret) {
1149 			dev_err(dev, "Failed to register %s hash!\n",
1150 				dcp_sha256_alg.halg.base.cra_name);
1151 			goto err_unregister_sha1;
1152 		}
1153 	}
1154 
1155 	return 0;
1156 
1157 err_unregister_sha1:
1158 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1159 		crypto_unregister_ahash(&dcp_sha1_alg);
1160 
1161 err_unregister_aes:
1162 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1163 		crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1164 
1165 err_destroy_aes_thread:
1166 	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1167 
1168 err_destroy_sha_thread:
1169 	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1170 
1171 err_disable_unprepare_clk:
1172 	clk_disable_unprepare(sdcp->dcp_clk);
1173 
1174 	return ret;
1175 }
1176 
1177 static int mxs_dcp_remove(struct platform_device *pdev)
1178 {
1179 	struct dcp *sdcp = platform_get_drvdata(pdev);
1180 
1181 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
1182 		crypto_unregister_ahash(&dcp_sha256_alg);
1183 
1184 	if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1185 		crypto_unregister_ahash(&dcp_sha1_alg);
1186 
1187 	if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1188 		crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1189 
1190 	kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1191 	kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1192 
1193 	clk_disable_unprepare(sdcp->dcp_clk);
1194 
1195 	platform_set_drvdata(pdev, NULL);
1196 
1197 	global_sdcp = NULL;
1198 
1199 	return 0;
1200 }
1201 
1202 static const struct of_device_id mxs_dcp_dt_ids[] = {
1203 	{ .compatible = "fsl,imx23-dcp", .data = NULL, },
1204 	{ .compatible = "fsl,imx28-dcp", .data = NULL, },
1205 	{ /* sentinel */ }
1206 };
1207 
1208 MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
1209 
1210 static struct platform_driver mxs_dcp_driver = {
1211 	.probe	= mxs_dcp_probe,
1212 	.remove	= mxs_dcp_remove,
1213 	.driver	= {
1214 		.name		= "mxs-dcp",
1215 		.of_match_table	= mxs_dcp_dt_ids,
1216 	},
1217 };
1218 
1219 module_platform_driver(mxs_dcp_driver);
1220 
1221 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
1222 MODULE_DESCRIPTION("Freescale MXS DCP Driver");
1223 MODULE_LICENSE("GPL");
1224 MODULE_ALIAS("platform:mxs-dcp");
1225