Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1264 insertions, 0 deletions

diff --git a/drivers/crypto/keembay/keembay-ocs-hcu-core.c b/drivers/crypto/keembay/keembay-ocs-hcu-core.c
new file mode 100644
index 000000000..0379dbf32
--- /dev/null
+++ b/drivers/crypto/keembay/keembay-ocs-hcu-core.c
@@ -0,0 +1,1264 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Keem Bay OCS HCU Crypto Driver.
+ *
+ * Copyright (C) 2018-2020 Intel Corporation
+ */
+
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+#include <crypto/engine.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/sha2.h>
+#include <crypto/sm3.h>
+#include <crypto/hmac.h>
+#include <crypto/internal/hash.h>
+
+#include "ocs-hcu.h"
+
+#define DRV_NAME	"keembay-ocs-hcu"
+
+/* Flag marking a final request. */
+#define REQ_FINAL			BIT(0)
+/* Flag marking a HMAC request. */
+#define REQ_FLAGS_HMAC			BIT(1)
+/* Flag set when HW HMAC is being used. */
+#define REQ_FLAGS_HMAC_HW		BIT(2)
+/* Flag set when SW HMAC is being used. */
+#define REQ_FLAGS_HMAC_SW		BIT(3)
+
+/**
+ * struct ocs_hcu_ctx: OCS HCU Transform context.
+ * @engine_ctx:	 Crypto Engine context.
+ * @hcu_dev:	 The OCS HCU device used by the transformation.
+ * @key:	 The key (used only for HMAC transformations).
+ * @key_len:	 The length of the key.
+ * @is_sm3_tfm:  Whether or not this is an SM3 transformation.
+ * @is_hmac_tfm: Whether or not this is a HMAC transformation.
+ */
+struct ocs_hcu_ctx {
+	struct crypto_engine_ctx engine_ctx;
+	struct ocs_hcu_dev *hcu_dev;
+	u8 key[SHA512_BLOCK_SIZE];
+	size_t key_len;
+	bool is_sm3_tfm;
+	bool is_hmac_tfm;
+};
+
+/**
+ * struct ocs_hcu_rctx - Context for the request.
+ * @hcu_dev:	    OCS HCU device to be used to service the request.
+ * @flags:	    Flags tracking request status.
+ * @algo:	    Algorithm to use for the request.
+ * @blk_sz:	    Block size of the transformation / request.
+ * @dig_sz:	    Digest size of the transformation / request.
+ * @dma_list:	    OCS DMA linked list.
+ * @hash_ctx:	    OCS HCU hashing context.
+ * @buffer:	    Buffer to store: partial block of data and SW HMAC
+ *		    artifacts (ipad, opad, etc.).
+ * @buf_cnt:	    Number of bytes currently stored in the buffer.
+ * @buf_dma_addr:   The DMA address of @buffer (when mapped).
+ * @buf_dma_count:  The number of bytes in @buffer currently DMA-mapped.
+ * @sg:		    Head of the scatterlist entries containing data.
+ * @sg_data_total:  Total data in the SG list at any time.
+ * @sg_data_offset: Offset into the data of the current individual SG node.
+ * @sg_dma_nents:   Number of sg entries mapped in dma_list.
+ */
+struct ocs_hcu_rctx {
+	struct ocs_hcu_dev	*hcu_dev;
+	u32			flags;
+	enum ocs_hcu_algo	algo;
+	size_t			blk_sz;
+	size_t			dig_sz;
+	struct ocs_hcu_dma_list	*dma_list;
+	struct ocs_hcu_hash_ctx	hash_ctx;
+	/*
+	 * Buffer is double the block size because we need space for SW HMAC
+	 * artifacts, i.e:
+	 * - ipad (1 block) + a possible partial block of data.
+	 * - opad (1 block) + digest of H(k ^ ipad || m)
+	 */
+	u8			buffer[2 * SHA512_BLOCK_SIZE];
+	size_t			buf_cnt;
+	dma_addr_t		buf_dma_addr;
+	size_t			buf_dma_count;
+	struct scatterlist	*sg;
+	unsigned int		sg_data_total;
+	unsigned int		sg_data_offset;
+	unsigned int		sg_dma_nents;
+};
+
+/**
+ * struct ocs_hcu_drv - Driver data
+ * @dev_list:	The list of HCU devices.
+ * @lock:	The lock protecting dev_list.
+ */
+struct ocs_hcu_drv {
+	struct list_head dev_list;
+	spinlock_t lock; /* Protects dev_list. */
+};
+
+static struct ocs_hcu_drv ocs_hcu = {
+	.dev_list = LIST_HEAD_INIT(ocs_hcu.dev_list),
+	.lock = __SPIN_LOCK_UNLOCKED(ocs_hcu.lock),
+};
+
+/*
+ * Return the total amount of data in the request; that is: the data in the
+ * request buffer + the data in the sg list.
+ */
+static inline unsigned int kmb_get_total_data(struct ocs_hcu_rctx *rctx)
+{
+	return rctx->sg_data_total + rctx->buf_cnt;
+}
+
+/* Move remaining content of scatter-gather list to context buffer. */
+static int flush_sg_to_ocs_buffer(struct ocs_hcu_rctx *rctx)
+{
+	size_t count;
+
+	if (rctx->sg_data_total > (sizeof(rctx->buffer) - rctx->buf_cnt)) {
+		WARN(1, "%s: sg data does not fit in buffer\n", __func__);
+		return -EINVAL;
+	}
+
+	while (rctx->sg_data_total) {
+		if (!rctx->sg) {
+			WARN(1, "%s: unexpected NULL sg\n", __func__);
+			return -EINVAL;
+		}
+		/*
+		 * If current sg has been fully processed, skip to the next
+		 * one.
+		 */
+		if (rctx->sg_data_offset == rctx->sg->length) {
+			rctx->sg = sg_next(rctx->sg);
+			rctx->sg_data_offset = 0;
+			continue;
+		}
+		/*
+		 * Determine the maximum data available to copy from the node.
+		 * Minimum of the length left in the sg node, or the total data
+		 * in the request.
+		 */
+		count = min(rctx->sg->length - rctx->sg_data_offset,
+			    rctx->sg_data_total);
+		/* Copy from scatter-list entry to context buffer. */
+		scatterwalk_map_and_copy(&rctx->buffer[rctx->buf_cnt],
+					 rctx->sg, rctx->sg_data_offset,
+					 count, 0);
+
+		rctx->sg_data_offset += count;
+		rctx->sg_data_total -= count;
+		rctx->buf_cnt += count;
+	}
+
+	return 0;
+}
+
+static struct ocs_hcu_dev *kmb_ocs_hcu_find_dev(struct ahash_request *req)
+{
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct ocs_hcu_ctx *tctx = crypto_ahash_ctx(tfm);
+
+	/* If the HCU device for the request was previously set, return it. */
+	if (tctx->hcu_dev)
+		return tctx->hcu_dev;
+
+	/*
+	 * Otherwise, get the first HCU device available (there should be one
+	 * and only one device).
+	 */
+	spin_lock_bh(&ocs_hcu.lock);
+	tctx->hcu_dev = list_first_entry_or_null(&ocs_hcu.dev_list,
+						 struct ocs_hcu_dev,
+						 list);
+	spin_unlock_bh(&ocs_hcu.lock);
+
+	return tctx->hcu_dev;
+}
+
+/* Free OCS DMA linked list and DMA-able context buffer. */
+static void kmb_ocs_hcu_dma_cleanup(struct ahash_request *req,
+				    struct ocs_hcu_rctx *rctx)
+{
+	struct ocs_hcu_dev *hcu_dev = rctx->hcu_dev;
+	struct device *dev = hcu_dev->dev;
+
+	/* Unmap rctx->buffer (if mapped). */
+	if (rctx->buf_dma_count) {
+		dma_unmap_single(dev, rctx->buf_dma_addr, rctx->buf_dma_count,
+				 DMA_TO_DEVICE);
+		rctx->buf_dma_count = 0;
+	}
+
+	/* Unmap req->src (if mapped). */
+	if (rctx->sg_dma_nents) {
+		dma_unmap_sg(dev, req->src, rctx->sg_dma_nents, DMA_TO_DEVICE);
+		rctx->sg_dma_nents = 0;
+	}
+
+	/* Free dma_list (if allocated). */
+	if (rctx->dma_list) {
+		ocs_hcu_dma_list_free(hcu_dev, rctx->dma_list);
+		rctx->dma_list = NULL;
+	}
+}
+
+/*
+ * Prepare for DMA operation:
+ * - DMA-map request context buffer (if needed)
+ * - DMA-map SG list (only the entries to be processed, see note below)
+ * - Allocate OCS HCU DMA linked list (number of elements =  SG entries to
+ *   process + context buffer (if not empty)).
+ * - Add DMA-mapped request context buffer to OCS HCU DMA list.
+ * - Add SG entries to DMA list.
+ *
+ * Note: if this is a final request, we process all the data in the SG list,
+ * otherwise we can only process up to the maximum amount of block-aligned data
+ * (the remainder will be put into the context buffer and processed in the next
+ * request).
+ */
+static int kmb_ocs_dma_prepare(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	struct device *dev = rctx->hcu_dev->dev;
+	unsigned int remainder = 0;
+	unsigned int total;
+	size_t nents;
+	size_t count;
+	int rc;
+	int i;
+
+	/* This function should be called only when there is data to process. */
+	total = kmb_get_total_data(rctx);
+	if (!total)
+		return -EINVAL;
+
+	/*
+	 * If this is not a final DMA (terminated DMA), the data passed to the
+	 * HCU must be aligned to the block size; compute the remainder data to
+	 * be processed in the next request.
+	 */
+	if (!(rctx->flags & REQ_FINAL))
+		remainder = total % rctx->blk_sz;
+
+	/* Determine the number of scatter gather list entries to process. */
+	nents = sg_nents_for_len(req->src, rctx->sg_data_total - remainder);
+
+	/* If there are entries to process, map them. */
+	if (nents) {
+		rctx->sg_dma_nents = dma_map_sg(dev, req->src, nents,
+						DMA_TO_DEVICE);
+		if (!rctx->sg_dma_nents) {
+			dev_err(dev, "Failed to MAP SG\n");
+			rc = -ENOMEM;
+			goto cleanup;
+		}
+		/*
+		 * The value returned by dma_map_sg() can be < nents; so update
+		 * nents accordingly.
+		 */
+		nents = rctx->sg_dma_nents;
+	}
+
+	/*
+	 * If context buffer is not empty, map it and add extra DMA entry for
+	 * it.
+	 */
+	if (rctx->buf_cnt) {
+		rctx->buf_dma_addr = dma_map_single(dev, rctx->buffer,
+						    rctx->buf_cnt,
+						    DMA_TO_DEVICE);
+		if (dma_mapping_error(dev, rctx->buf_dma_addr)) {
+			dev_err(dev, "Failed to map request context buffer\n");
+			rc = -ENOMEM;
+			goto cleanup;
+		}
+		rctx->buf_dma_count = rctx->buf_cnt;
+		/* Increase number of dma entries. */
+		nents++;
+	}
+
+	/* Allocate OCS HCU DMA list. */
+	rctx->dma_list = ocs_hcu_dma_list_alloc(rctx->hcu_dev, nents);
+	if (!rctx->dma_list) {
+		rc = -ENOMEM;
+		goto cleanup;
+	}
+
+	/* Add request context buffer (if previously DMA-mapped) */
+	if (rctx->buf_dma_count) {
+		rc = ocs_hcu_dma_list_add_tail(rctx->hcu_dev, rctx->dma_list,
+					       rctx->buf_dma_addr,
+					       rctx->buf_dma_count);
+		if (rc)
+			goto cleanup;
+	}
+
+	/* Add the SG nodes to be processed to the DMA linked list. */
+	for_each_sg(req->src, rctx->sg, rctx->sg_dma_nents, i) {
+		/*
+		 * The number of bytes to add to the list entry is the minimum
+		 * between:
+		 * - The DMA length of the SG entry.
+		 * - The data left to be processed.
+		 */
+		count = min(rctx->sg_data_total - remainder,
+			    sg_dma_len(rctx->sg) - rctx->sg_data_offset);
+		/*
+		 * Do not create a zero length DMA descriptor. Check in case of
+		 * zero length SG node.
+		 */
+		if (count == 0)
+			continue;
+		/* Add sg to HCU DMA list. */
+		rc = ocs_hcu_dma_list_add_tail(rctx->hcu_dev,
+					       rctx->dma_list,
+					       rctx->sg->dma_address,
+					       count);
+		if (rc)
+			goto cleanup;
+
+		/* Update amount of data remaining in SG list. */
+		rctx->sg_data_total -= count;
+
+		/*
+		 * If  remaining data is equal to remainder (note: 'less than'
+		 * case should never happen in practice), we are done: update
+		 * offset and exit the loop.
+		 */
+		if (rctx->sg_data_total <= remainder) {
+			WARN_ON(rctx->sg_data_total < remainder);
+			rctx->sg_data_offset += count;
+			break;
+		}
+
+		/*
+		 * If we get here is because we need to process the next sg in
+		 * the list; set offset within the sg to 0.
+		 */
+		rctx->sg_data_offset = 0;
+	}
+
+	return 0;
+cleanup:
+	dev_err(dev, "Failed to prepare DMA.\n");
+	kmb_ocs_hcu_dma_cleanup(req, rctx);
+
+	return rc;
+}
+
+static void kmb_ocs_hcu_secure_cleanup(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+
+	/* Clear buffer of any data. */
+	memzero_explicit(rctx->buffer, sizeof(rctx->buffer));
+}
+
+static int kmb_ocs_hcu_handle_queue(struct ahash_request *req)
+{
+	struct ocs_hcu_dev *hcu_dev = kmb_ocs_hcu_find_dev(req);
+
+	if (!hcu_dev)
+		return -ENOENT;
+
+	return crypto_transfer_hash_request_to_engine(hcu_dev->engine, req);
+}
+
+static int prepare_ipad(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct ocs_hcu_ctx *ctx = crypto_ahash_ctx(tfm);
+	int i;
+
+	WARN(rctx->buf_cnt, "%s: Context buffer is not empty\n", __func__);
+	WARN(!(rctx->flags & REQ_FLAGS_HMAC_SW),
+	     "%s: HMAC_SW flag is not set\n", __func__);
+	/*
+	 * Key length must be equal to block size. If key is shorter,
+	 * we pad it with zero (note: key cannot be longer, since
+	 * longer keys are hashed by kmb_ocs_hcu_setkey()).
+	 */
+	if (ctx->key_len > rctx->blk_sz) {
+		WARN(1, "%s: Invalid key length in tfm context\n", __func__);
+		return -EINVAL;
+	}
+	memzero_explicit(&ctx->key[ctx->key_len],
+			 rctx->blk_sz - ctx->key_len);
+	ctx->key_len = rctx->blk_sz;
+	/*
+	 * Prepare IPAD for HMAC. Only done for first block.
+	 * HMAC(k,m) = H(k ^ opad || H(k ^ ipad || m))
+	 * k ^ ipad will be first hashed block.
+	 * k ^ opad will be calculated in the final request.
+	 * Only needed if not using HW HMAC.
+	 */
+	for (i = 0; i < rctx->blk_sz; i++)
+		rctx->buffer[i] = ctx->key[i] ^ HMAC_IPAD_VALUE;
+	rctx->buf_cnt = rctx->blk_sz;
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_do_one_request(struct crypto_engine *engine, void *areq)
+{
+	struct ahash_request *req = container_of(areq, struct ahash_request,
+						 base);
+	struct ocs_hcu_dev *hcu_dev = kmb_ocs_hcu_find_dev(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	struct ocs_hcu_ctx *tctx = crypto_ahash_ctx(tfm);
+	int rc;
+	int i;
+
+	if (!hcu_dev) {
+		rc = -ENOENT;
+		goto error;
+	}
+
+	/*
+	 * If hardware HMAC flag is set, perform HMAC in hardware.
+	 *
+	 * NOTE: this flag implies REQ_FINAL && kmb_get_total_data(rctx)
+	 */
+	if (rctx->flags & REQ_FLAGS_HMAC_HW) {
+		/* Map input data into the HCU DMA linked list. */
+		rc = kmb_ocs_dma_prepare(req);
+		if (rc)
+			goto error;
+
+		rc = ocs_hcu_hmac(hcu_dev, rctx->algo, tctx->key, tctx->key_len,
+				  rctx->dma_list, req->result, rctx->dig_sz);
+
+		/* Unmap data and free DMA list regardless of return code. */
+		kmb_ocs_hcu_dma_cleanup(req, rctx);
+
+		/* Process previous return code. */
+		if (rc)
+			goto error;
+
+		goto done;
+	}
+
+	/* Handle update request case. */
+	if (!(rctx->flags & REQ_FINAL)) {
+		/* Update should always have input data. */
+		if (!kmb_get_total_data(rctx))
+			return -EINVAL;
+
+		/* Map input data into the HCU DMA linked list. */
+		rc = kmb_ocs_dma_prepare(req);
+		if (rc)
+			goto error;
+
+		/* Do hashing step. */
+		rc = ocs_hcu_hash_update(hcu_dev, &rctx->hash_ctx,
+					 rctx->dma_list);
+
+		/* Unmap data and free DMA list regardless of return code. */
+		kmb_ocs_hcu_dma_cleanup(req, rctx);
+
+		/* Process previous return code. */
+		if (rc)
+			goto error;
+
+		/*
+		 * Reset request buffer count (data in the buffer was just
+		 * processed).
+		 */
+		rctx->buf_cnt = 0;
+		/*
+		 * Move remaining sg data into the request buffer, so that it
+		 * will be processed during the next request.
+		 *
+		 * NOTE: we have remaining data if kmb_get_total_data() was not
+		 * a multiple of block size.
+		 */
+		rc = flush_sg_to_ocs_buffer(rctx);
+		if (rc)
+			goto error;
+
+		goto done;
+	}
+
+	/* If we get here, this is a final request. */
+
+	/* If there is data to process, use finup. */
+	if (kmb_get_total_data(rctx)) {
+		/* Map input data into the HCU DMA linked list. */
+		rc = kmb_ocs_dma_prepare(req);
+		if (rc)
+			goto error;
+
+		/* Do hashing step. */
+		rc = ocs_hcu_hash_finup(hcu_dev, &rctx->hash_ctx,
+					rctx->dma_list,
+					req->result, rctx->dig_sz);
+		/* Free DMA list regardless of return code. */
+		kmb_ocs_hcu_dma_cleanup(req, rctx);
+
+		/* Process previous return code. */
+		if (rc)
+			goto error;
+
+	} else {  /* Otherwise (if we have no data), use final. */
+		rc = ocs_hcu_hash_final(hcu_dev, &rctx->hash_ctx, req->result,
+					rctx->dig_sz);
+		if (rc)
+			goto error;
+	}
+
+	/*
+	 * If we are finalizing a SW HMAC request, we just computed the result
+	 * of: H(k ^ ipad || m).
+	 *
+	 * We now need to complete the HMAC calculation with the OPAD step,
+	 * that is, we need to compute H(k ^ opad || digest), where digest is
+	 * the digest we just obtained, i.e., H(k ^ ipad || m).
+	 */
+	if (rctx->flags & REQ_FLAGS_HMAC_SW) {
+		/*
+		 * Compute k ^ opad and store it in the request buffer (which
+		 * is not used anymore at this point).
+		 * Note: key has been padded / hashed already (so keylen ==
+		 * blksz) .
+		 */
+		WARN_ON(tctx->key_len != rctx->blk_sz);
+		for (i = 0; i < rctx->blk_sz; i++)
+			rctx->buffer[i] = tctx->key[i] ^ HMAC_OPAD_VALUE;
+		/* Now append the digest to the rest of the buffer. */
+		for (i = 0; (i < rctx->dig_sz); i++)
+			rctx->buffer[rctx->blk_sz + i] = req->result[i];
+
+		/* Now hash the buffer to obtain the final HMAC. */
+		rc = ocs_hcu_digest(hcu_dev, rctx->algo, rctx->buffer,
+				    rctx->blk_sz + rctx->dig_sz, req->result,
+				    rctx->dig_sz);
+		if (rc)
+			goto error;
+	}
+
+	/* Perform secure clean-up. */
+	kmb_ocs_hcu_secure_cleanup(req);
+done:
+	crypto_finalize_hash_request(hcu_dev->engine, req, 0);
+
+	return 0;
+
+error:
+	kmb_ocs_hcu_secure_cleanup(req);
+	return rc;
+}
+
+static int kmb_ocs_hcu_init(struct ahash_request *req)
+{
+	struct ocs_hcu_dev *hcu_dev = kmb_ocs_hcu_find_dev(req);
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct ocs_hcu_ctx *ctx = crypto_ahash_ctx(tfm);
+
+	if (!hcu_dev)
+		return -ENOENT;
+
+	/* Initialize entire request context to zero. */
+	memset(rctx, 0, sizeof(*rctx));
+
+	rctx->hcu_dev = hcu_dev;
+	rctx->dig_sz = crypto_ahash_digestsize(tfm);
+
+	switch (rctx->dig_sz) {
+#ifdef CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224
+	case SHA224_DIGEST_SIZE:
+		rctx->blk_sz = SHA224_BLOCK_SIZE;
+		rctx->algo = OCS_HCU_ALGO_SHA224;
+		break;
+#endif /* CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224 */
+	case SHA256_DIGEST_SIZE:
+		rctx->blk_sz = SHA256_BLOCK_SIZE;
+		/*
+		 * SHA256 and SM3 have the same digest size: use info from tfm
+		 * context to find out which one we should use.
+		 */
+		rctx->algo = ctx->is_sm3_tfm ? OCS_HCU_ALGO_SM3 :
+					       OCS_HCU_ALGO_SHA256;
+		break;
+	case SHA384_DIGEST_SIZE:
+		rctx->blk_sz = SHA384_BLOCK_SIZE;
+		rctx->algo = OCS_HCU_ALGO_SHA384;
+		break;
+	case SHA512_DIGEST_SIZE:
+		rctx->blk_sz = SHA512_BLOCK_SIZE;
+		rctx->algo = OCS_HCU_ALGO_SHA512;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Initialize intermediate data. */
+	ocs_hcu_hash_init(&rctx->hash_ctx, rctx->algo);
+
+	/* If this a HMAC request, set HMAC flag. */
+	if (ctx->is_hmac_tfm)
+		rctx->flags |= REQ_FLAGS_HMAC;
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_update(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	int rc;
+
+	if (!req->nbytes)
+		return 0;
+
+	rctx->sg_data_total = req->nbytes;
+	rctx->sg_data_offset = 0;
+	rctx->sg = req->src;
+
+	/*
+	 * If we are doing HMAC, then we must use SW-assisted HMAC, since HW
+	 * HMAC does not support context switching (there it can only be used
+	 * with finup() or digest()).
+	 */
+	if (rctx->flags & REQ_FLAGS_HMAC &&
+	    !(rctx->flags & REQ_FLAGS_HMAC_SW)) {
+		rctx->flags |= REQ_FLAGS_HMAC_SW;
+		rc = prepare_ipad(req);
+		if (rc)
+			return rc;
+	}
+
+	/*
+	 * If remaining sg_data fits into ctx buffer, just copy it there; we'll
+	 * process it at the next update() or final().
+	 */
+	if (rctx->sg_data_total <= (sizeof(rctx->buffer) - rctx->buf_cnt))
+		return flush_sg_to_ocs_buffer(rctx);
+
+	return kmb_ocs_hcu_handle_queue(req);
+}
+
+/* Common logic for kmb_ocs_hcu_final() and kmb_ocs_hcu_finup(). */
+static int kmb_ocs_hcu_fin_common(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct ocs_hcu_ctx *ctx = crypto_ahash_ctx(tfm);
+	int rc;
+
+	rctx->flags |= REQ_FINAL;
+
+	/*
+	 * If this is a HMAC request and, so far, we didn't have to switch to
+	 * SW HMAC, check if we can use HW HMAC.
+	 */
+	if (rctx->flags & REQ_FLAGS_HMAC &&
+	    !(rctx->flags & REQ_FLAGS_HMAC_SW)) {
+		/*
+		 * If we are here, it means we never processed any data so far,
+		 * so we can use HW HMAC, but only if there is some data to
+		 * process (since OCS HW MAC does not support zero-length
+		 * messages) and the key length is supported by the hardware
+		 * (OCS HCU HW only supports length <= 64); if HW HMAC cannot
+		 * be used, fall back to SW-assisted HMAC.
+		 */
+		if (kmb_get_total_data(rctx) &&
+		    ctx->key_len <= OCS_HCU_HW_KEY_LEN) {
+			rctx->flags |= REQ_FLAGS_HMAC_HW;
+		} else {
+			rctx->flags |= REQ_FLAGS_HMAC_SW;
+			rc = prepare_ipad(req);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return kmb_ocs_hcu_handle_queue(req);
+}
+
+static int kmb_ocs_hcu_final(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+
+	rctx->sg_data_total = 0;
+	rctx->sg_data_offset = 0;
+	rctx->sg = NULL;
+
+	return kmb_ocs_hcu_fin_common(req);
+}
+
+static int kmb_ocs_hcu_finup(struct ahash_request *req)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+
+	rctx->sg_data_total = req->nbytes;
+	rctx->sg_data_offset = 0;
+	rctx->sg = req->src;
+
+	return kmb_ocs_hcu_fin_common(req);
+}
+
+static int kmb_ocs_hcu_digest(struct ahash_request *req)
+{
+	int rc = 0;
+	struct ocs_hcu_dev *hcu_dev = kmb_ocs_hcu_find_dev(req);
+
+	if (!hcu_dev)
+		return -ENOENT;
+
+	rc = kmb_ocs_hcu_init(req);
+	if (rc)
+		return rc;
+
+	rc = kmb_ocs_hcu_finup(req);
+
+	return rc;
+}
+
+static int kmb_ocs_hcu_export(struct ahash_request *req, void *out)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+
+	/* Intermediate data is always stored and applied per request. */
+	memcpy(out, rctx, sizeof(*rctx));
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_import(struct ahash_request *req, const void *in)
+{
+	struct ocs_hcu_rctx *rctx = ahash_request_ctx(req);
+
+	/* Intermediate data is always stored and applied per request. */
+	memcpy(rctx, in, sizeof(*rctx));
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_setkey(struct crypto_ahash *tfm, const u8 *key,
+			      unsigned int keylen)
+{
+	unsigned int digestsize = crypto_ahash_digestsize(tfm);
+	struct ocs_hcu_ctx *ctx = crypto_ahash_ctx(tfm);
+	size_t blk_sz = crypto_ahash_blocksize(tfm);
+	struct crypto_ahash *ahash_tfm;
+	struct ahash_request *req;
+	struct crypto_wait wait;
+	struct scatterlist sg;
+	const char *alg_name;
+	int rc;
+
+	/*
+	 * Key length must be equal to block size:
+	 * - If key is shorter, we are done for now (the key will be padded
+	 *   later on); this is to maximize the use of HW HMAC (which works
+	 *   only for keys <= 64 bytes).
+	 * - If key is longer, we hash it.
+	 */
+	if (keylen <= blk_sz) {
+		memcpy(ctx->key, key, keylen);
+		ctx->key_len = keylen;
+		return 0;
+	}
+
+	switch (digestsize) {
+#ifdef CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224
+	case SHA224_DIGEST_SIZE:
+		alg_name = "sha224-keembay-ocs";
+		break;
+#endif /* CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224 */
+	case SHA256_DIGEST_SIZE:
+		alg_name = ctx->is_sm3_tfm ? "sm3-keembay-ocs" :
+					     "sha256-keembay-ocs";
+		break;
+	case SHA384_DIGEST_SIZE:
+		alg_name = "sha384-keembay-ocs";
+		break;
+	case SHA512_DIGEST_SIZE:
+		alg_name = "sha512-keembay-ocs";
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ahash_tfm = crypto_alloc_ahash(alg_name, 0, 0);
+	if (IS_ERR(ahash_tfm))
+		return PTR_ERR(ahash_tfm);
+
+	req = ahash_request_alloc(ahash_tfm, GFP_KERNEL);
+	if (!req) {
+		rc = -ENOMEM;
+		goto err_free_ahash;
+	}
+
+	crypto_init_wait(&wait);
+	ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				   crypto_req_done, &wait);
+	crypto_ahash_clear_flags(ahash_tfm, ~0);
+
+	sg_init_one(&sg, key, keylen);
+	ahash_request_set_crypt(req, &sg, ctx->key, keylen);
+
+	rc = crypto_wait_req(crypto_ahash_digest(req), &wait);
+	if (rc == 0)
+		ctx->key_len = digestsize;
+
+	ahash_request_free(req);
+err_free_ahash:
+	crypto_free_ahash(ahash_tfm);
+
+	return rc;
+}
+
+/* Set request size and initialize tfm context. */
+static void __cra_init(struct crypto_tfm *tfm, struct ocs_hcu_ctx *ctx)
+{
+	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
+				 sizeof(struct ocs_hcu_rctx));
+
+	/* Init context to 0. */
+	memzero_explicit(ctx, sizeof(*ctx));
+	/* Set engine ops. */
+	ctx->engine_ctx.op.do_one_request = kmb_ocs_hcu_do_one_request;
+}
+
+static int kmb_ocs_hcu_sha_cra_init(struct crypto_tfm *tfm)
+{
+	struct ocs_hcu_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	__cra_init(tfm, ctx);
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_sm3_cra_init(struct crypto_tfm *tfm)
+{
+	struct ocs_hcu_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	__cra_init(tfm, ctx);
+
+	ctx->is_sm3_tfm = true;
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_hmac_sm3_cra_init(struct crypto_tfm *tfm)
+{
+	struct ocs_hcu_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	__cra_init(tfm, ctx);
+
+	ctx->is_sm3_tfm = true;
+	ctx->is_hmac_tfm = true;
+
+	return 0;
+}
+
+static int kmb_ocs_hcu_hmac_cra_init(struct crypto_tfm *tfm)
+{
+	struct ocs_hcu_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	__cra_init(tfm, ctx);
+
+	ctx->is_hmac_tfm = true;
+
+	return 0;
+}
+
+/* Function called when 'tfm' is de-initialized. */
+static void kmb_ocs_hcu_hmac_cra_exit(struct crypto_tfm *tfm)
+{
+	struct ocs_hcu_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	/* Clear the key. */
+	memzero_explicit(ctx->key, sizeof(ctx->key));
+}
+
+static struct ahash_alg ocs_hcu_algs[] = {
+#ifdef CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.halg = {
+		.digestsize	= SHA224_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "sha224",
+			.cra_driver_name	= "sha224-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA224_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_sha_cra_init,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.setkey		= kmb_ocs_hcu_setkey,
+	.halg = {
+		.digestsize	= SHA224_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "hmac(sha224)",
+			.cra_driver_name	= "hmac-sha224-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA224_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_hmac_cra_init,
+			.cra_exit		= kmb_ocs_hcu_hmac_cra_exit,
+		}
+	}
+},
+#endif /* CONFIG_CRYPTO_DEV_KEEMBAY_OCS_HCU_HMAC_SHA224 */
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.halg = {
+		.digestsize	= SHA256_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "sha256",
+			.cra_driver_name	= "sha256-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA256_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_sha_cra_init,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.setkey		= kmb_ocs_hcu_setkey,
+	.halg = {
+		.digestsize	= SHA256_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "hmac(sha256)",
+			.cra_driver_name	= "hmac-sha256-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA256_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_hmac_cra_init,
+			.cra_exit		= kmb_ocs_hcu_hmac_cra_exit,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.halg = {
+		.digestsize	= SM3_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "sm3",
+			.cra_driver_name	= "sm3-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SM3_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_sm3_cra_init,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.setkey		= kmb_ocs_hcu_setkey,
+	.halg = {
+		.digestsize	= SM3_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "hmac(sm3)",
+			.cra_driver_name	= "hmac-sm3-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SM3_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_hmac_sm3_cra_init,
+			.cra_exit		= kmb_ocs_hcu_hmac_cra_exit,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.halg = {
+		.digestsize	= SHA384_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "sha384",
+			.cra_driver_name	= "sha384-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA384_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_sha_cra_init,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.setkey		= kmb_ocs_hcu_setkey,
+	.halg = {
+		.digestsize	= SHA384_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "hmac(sha384)",
+			.cra_driver_name	= "hmac-sha384-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA384_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_hmac_cra_init,
+			.cra_exit		= kmb_ocs_hcu_hmac_cra_exit,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.halg = {
+		.digestsize	= SHA512_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "sha512",
+			.cra_driver_name	= "sha512-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA512_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_sha_cra_init,
+		}
+	}
+},
+{
+	.init		= kmb_ocs_hcu_init,
+	.update		= kmb_ocs_hcu_update,
+	.final		= kmb_ocs_hcu_final,
+	.finup		= kmb_ocs_hcu_finup,
+	.digest		= kmb_ocs_hcu_digest,
+	.export		= kmb_ocs_hcu_export,
+	.import		= kmb_ocs_hcu_import,
+	.setkey		= kmb_ocs_hcu_setkey,
+	.halg = {
+		.digestsize	= SHA512_DIGEST_SIZE,
+		.statesize	= sizeof(struct ocs_hcu_rctx),
+		.base	= {
+			.cra_name		= "hmac(sha512)",
+			.cra_driver_name	= "hmac-sha512-keembay-ocs",
+			.cra_priority		= 255,
+			.cra_flags		= CRYPTO_ALG_ASYNC,
+			.cra_blocksize		= SHA512_BLOCK_SIZE,
+			.cra_ctxsize		= sizeof(struct ocs_hcu_ctx),
+			.cra_alignmask		= 0,
+			.cra_module		= THIS_MODULE,
+			.cra_init		= kmb_ocs_hcu_hmac_cra_init,
+			.cra_exit		= kmb_ocs_hcu_hmac_cra_exit,
+		}
+	}
+},
+};
+
+/* Device tree driver match. */
+static const struct of_device_id kmb_ocs_hcu_of_match[] = {
+	{
+		.compatible = "intel,keembay-ocs-hcu",
+	},
+	{}
+};
+
+static int kmb_ocs_hcu_remove(struct platform_device *pdev)
+{
+	struct ocs_hcu_dev *hcu_dev;
+	int rc;
+
+	hcu_dev = platform_get_drvdata(pdev);
+	if (!hcu_dev)
+		return -ENODEV;
+
+	crypto_unregister_ahashes(ocs_hcu_algs, ARRAY_SIZE(ocs_hcu_algs));
+
+	rc = crypto_engine_exit(hcu_dev->engine);
+
+	spin_lock_bh(&ocs_hcu.lock);
+	list_del(&hcu_dev->list);
+	spin_unlock_bh(&ocs_hcu.lock);
+
+	return rc;
+}
+
+static int kmb_ocs_hcu_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ocs_hcu_dev *hcu_dev;
+	struct resource *hcu_mem;
+	int rc;
+
+	hcu_dev = devm_kzalloc(dev, sizeof(*hcu_dev), GFP_KERNEL);
+	if (!hcu_dev)
+		return -ENOMEM;
+
+	hcu_dev->dev = dev;
+
+	platform_set_drvdata(pdev, hcu_dev);
+	rc = dma_set_mask_and_coherent(&pdev->dev, OCS_HCU_DMA_BIT_MASK);
+	if (rc)
+		return rc;
+
+	/* Get the memory address and remap. */
+	hcu_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!hcu_mem) {
+		dev_err(dev, "Could not retrieve io mem resource.\n");
+		return -ENODEV;
+	}
+
+	hcu_dev->io_base = devm_ioremap_resource(dev, hcu_mem);
+	if (IS_ERR(hcu_dev->io_base))
+		return PTR_ERR(hcu_dev->io_base);
+
+	init_completion(&hcu_dev->irq_done);
+
+	/* Get and request IRQ. */
+	hcu_dev->irq = platform_get_irq(pdev, 0);
+	if (hcu_dev->irq < 0)
+		return hcu_dev->irq;
+
+	rc = devm_request_threaded_irq(&pdev->dev, hcu_dev->irq,
+				       ocs_hcu_irq_handler, NULL, 0,
+				       "keembay-ocs-hcu", hcu_dev);
+	if (rc < 0) {
+		dev_err(dev, "Could not request IRQ.\n");
+		return rc;
+	}
+
+	INIT_LIST_HEAD(&hcu_dev->list);
+
+	spin_lock_bh(&ocs_hcu.lock);
+	list_add_tail(&hcu_dev->list, &ocs_hcu.dev_list);
+	spin_unlock_bh(&ocs_hcu.lock);
+
+	/* Initialize crypto engine */
+	hcu_dev->engine = crypto_engine_alloc_init(dev, 1);
+	if (!hcu_dev->engine) {
+		rc = -ENOMEM;
+		goto list_del;
+	}
+
+	rc = crypto_engine_start(hcu_dev->engine);
+	if (rc) {
+		dev_err(dev, "Could not start engine.\n");
+		goto cleanup;
+	}
+
+	/* Security infrastructure guarantees OCS clock is enabled. */
+
+	rc = crypto_register_ahashes(ocs_hcu_algs, ARRAY_SIZE(ocs_hcu_algs));
+	if (rc) {
+		dev_err(dev, "Could not register algorithms.\n");
+		goto cleanup;
+	}
+
+	return 0;
+
+cleanup:
+	crypto_engine_exit(hcu_dev->engine);
+list_del:
+	spin_lock_bh(&ocs_hcu.lock);
+	list_del(&hcu_dev->list);
+	spin_unlock_bh(&ocs_hcu.lock);
+
+	return rc;
+}
+
+/* The OCS driver is a platform device. */
+static struct platform_driver kmb_ocs_hcu_driver = {
+	.probe = kmb_ocs_hcu_probe,
+	.remove = kmb_ocs_hcu_remove,
+	.driver = {
+			.name = DRV_NAME,
+			.of_match_table = kmb_ocs_hcu_of_match,
+		},
+};
+
+module_platform_driver(kmb_ocs_hcu_driver);
+
+MODULE_LICENSE("GPL");