// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) ST-Ericsson SA 2010
 * Author: Shujuan Chen <shujuan.chen@stericsson.com> for ST-Ericsson.
 * Author: Joakim Bech <joakim.xx.bech@stericsson.com> for ST-Ericsson.
 * Author: Berne Hebark <berne.herbark@stericsson.com> for ST-Ericsson.
 * Author: Niklas Hernaeus <niklas.hernaeus@stericsson.com> for ST-Ericsson.
 * Author: Jonas Linde <jonas.linde@stericsson.com> for ST-Ericsson.
 * Author: Andreas Westin <andreas.westin@stericsson.com> for ST-Ericsson.
 */

#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irqreturn.h>
#include <linux/kernel.h>
#include <linux/klist.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/semaphore.h>
#include <linux/platform_data/dma-ste-dma40.h>

#include <crypto/aes.h>
#include <crypto/ctr.h>
#include <crypto/internal/des.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>

#include <linux/platform_data/crypto-ux500.h>

#include "cryp_p.h"
#include "cryp.h"

#define CRYP_MAX_KEY_SIZE       32
#define BYTES_PER_WORD          4

static int cryp_mode;
static atomic_t session_id;

static struct stedma40_chan_cfg *mem_to_engine;
static struct stedma40_chan_cfg *engine_to_mem;

/**
 * struct cryp_driver_data - data specific to the driver.
 *
 * @device_list: A list of registered devices to choose from.
 * @device_allocation: A semaphore initialized with number of devices.
 */
struct cryp_driver_data {
        struct klist device_list;
        struct semaphore device_allocation;
};

/**
 * struct cryp_ctx - Crypto context
 * @config: Crypto mode.
 * @key: Key array.
 * @keylen: Length of key.
 * @iv: Pointer to initialization vector.
 * @indata: Pointer to indata.
 * @outdata: Pointer to outdata.
 * @datalen: Length of indata.
 * @outlen: Length of outdata.
 * @blocksize: Size of blocks.
 * @updated: Updated flag.
 * @dev_ctx: Device dependent context.
 * @device: Pointer to the device.
 * @session_id: Atomic session ID.
 */
struct cryp_ctx {
        struct cryp_config config;
        u8 key[CRYP_MAX_KEY_SIZE];
        u32 keylen;
        u8 *iv;
        const u8 *indata;
        u8 *outdata;
        u32 datalen;
        u32 outlen;
        u32 blocksize;
        u8 updated;
        struct cryp_device_context dev_ctx;
        struct cryp_device_data *device;
        u32 session_id;
};

static struct cryp_driver_data driver_data;

/**
 * swap_bits_in_byte - mirror the bits in a byte
 * @b: the byte to be mirrored
 *
 * The bits are swapped the following way:
 *  Byte b include bits 0-7, nibble 1 (n1) include bits 0-3 and
 *  nibble 2 (n2) bits 4-7.
 *
 *  Nibble 1 (n1):
 *  (The "old" (moved) bit is replaced with a zero)
 *  1. Move bit 6 and 7, 4 positions to the left.
 *  2. Move bit 3 and 5, 2 positions to the left.
 *  3. Move bit 1-4, 1 position to the left.
 *
 *  Nibble 2 (n2):
 *  1. Move bit 0 and 1, 4 positions to the right.
 *  2. Move bit 2 and 4, 2 positions to the right.
 *  3. Move bit 3-6, 1 position to the right.
 *
 *  Combine the two nibbles to a complete and swapped byte.
 */

static inline u8 swap_bits_in_byte(u8 b)
{
#define R_SHIFT_4_MASK  0xc0 /* Bits 6 and 7, right shift 4 */
#define R_SHIFT_2_MASK  0x28 /* (After right shift 4) Bits 3 and 5,
                                  right shift 2 */
#define R_SHIFT_1_MASK  0x1e /* (After right shift 2) Bits 1-4,
                                  right shift 1 */
#define L_SHIFT_4_MASK  0x03 /* Bits 0 and 1, left shift 4 */
#define L_SHIFT_2_MASK  0x14 /* (After left shift 4) Bits 2 and 4,
                                  left shift 2 */
#define L_SHIFT_1_MASK  0x78 /* (After left shift 1) Bits 3-6,
                                  left shift 1 */

        u8 n1;
        u8 n2;

        /* Swap most significant nibble */
        /* Right shift 4, bits 6 and 7 */
        n1 = ((b  & R_SHIFT_4_MASK) >> 4) | (b  & ~(R_SHIFT_4_MASK >> 4));
        /* Right shift 2, bits 3 and 5 */
        n1 = ((n1 & R_SHIFT_2_MASK) >> 2) | (n1 & ~(R_SHIFT_2_MASK >> 2));
        /* Right shift 1, bits 1-4 */
        n1 = (n1  & R_SHIFT_1_MASK) >> 1;

        /* Swap least significant nibble */
        /* Left shift 4, bits 0 and 1 */
        n2 = ((b  & L_SHIFT_4_MASK) << 4) | (b  & ~(L_SHIFT_4_MASK << 4));
        /* Left shift 2, bits 2 and 4 */
        n2 = ((n2 & L_SHIFT_2_MASK) << 2) | (n2 & ~(L_SHIFT_2_MASK << 2));
        /* Left shift 1, bits 3-6 */
        n2 = (n2  & L_SHIFT_1_MASK) << 1;

        return n1 | n2;
}

static inline void swap_words_in_key_and_bits_in_byte(const u8 *in,
                                                      u8 *out, u32 len)
{
        unsigned int i = 0;
        int j;
        int index = 0;

        j = len - BYTES_PER_WORD;
        while (j >= 0) {
                for (i = 0; i < BYTES_PER_WORD; i++) {
                        index = len - j - BYTES_PER_WORD + i;
                        out[j + i] =
                                swap_bits_in_byte(in[index]);
                }
                j -= BYTES_PER_WORD;
        }
}

static void add_session_id(struct cryp_ctx *ctx)
{
        /*
         * We never want 0 to be a valid value, since this is the default value
         * for the software context.
         */
        if (unlikely(atomic_inc_and_test(&session_id)))
                atomic_inc(&session_id);

        ctx->session_id = atomic_read(&session_id);
}

static irqreturn_t cryp_interrupt_handler(int irq, void *param)
{
        struct cryp_ctx *ctx;
        int count;
        struct cryp_device_data *device_data;

        if (param == NULL) {
                BUG_ON(!param);
                return IRQ_HANDLED;
        }

        /* The device is coming from the one found in hw_crypt_noxts. */
        device_data = (struct cryp_device_data *)param;

        ctx = device_data->current_ctx;

        if (ctx == NULL) {
                BUG_ON(!ctx);
                return IRQ_HANDLED;
        }

        dev_dbg(ctx->device->dev, "[%s] (len: %d) %s, ", __func__, ctx->outlen,
                cryp_pending_irq_src(device_data, CRYP_IRQ_SRC_OUTPUT_FIFO) ?
                "out" : "in");

        if (cryp_pending_irq_src(device_data,
                                 CRYP_IRQ_SRC_OUTPUT_FIFO)) {
                if (ctx->outlen / ctx->blocksize > 0) {
                        count = ctx->blocksize / 4;

                        readsl(&device_data->base->dout, ctx->outdata, count);
                        ctx->outdata += count;
                        ctx->outlen -= count;

                        if (ctx->outlen == 0) {
                                cryp_disable_irq_src(device_data,
                                                     CRYP_IRQ_SRC_OUTPUT_FIFO);
                        }
                }
        } else if (cryp_pending_irq_src(device_data,
                                        CRYP_IRQ_SRC_INPUT_FIFO)) {
                if (ctx->datalen / ctx->blocksize > 0) {
                        count = ctx->blocksize / 4;

                        writesl(&device_data->base->din, ctx->indata, count);

                        ctx->indata += count;
                        ctx->datalen -= count;

                        if (ctx->datalen == 0)
                                cryp_disable_irq_src(device_data,
                                                   CRYP_IRQ_SRC_INPUT_FIFO);

                        if (ctx->config.algomode == CRYP_ALGO_AES_XTS) {
                                CRYP_PUT_BITS(&device_data->base->cr,
                                              CRYP_START_ENABLE,
                                              CRYP_CR_START_POS,
                                              CRYP_CR_START_MASK);

                                cryp_wait_until_done(device_data);
                        }
                }
        }

        return IRQ_HANDLED;
}

static int mode_is_aes(enum cryp_algo_mode mode)
{
        return  CRYP_ALGO_AES_ECB == mode ||
                CRYP_ALGO_AES_CBC == mode ||
                CRYP_ALGO_AES_CTR == mode ||
                CRYP_ALGO_AES_XTS == mode;
}

static int cfg_iv(struct cryp_device_data *device_data, u32 left, u32 right,
                  enum cryp_init_vector_index index)
{
        struct cryp_init_vector_value vector_value;

        dev_dbg(device_data->dev, "[%s]", __func__);

        vector_value.init_value_left = left;
        vector_value.init_value_right = right;

        return cryp_configure_init_vector(device_data,
                                          index,
                                          vector_value);
}

static int cfg_ivs(struct cryp_device_data *device_data, struct cryp_ctx *ctx)
{
        int i;
        int status = 0;
        int num_of_regs = ctx->blocksize / 8;
        __be32 *civ = (__be32 *)ctx->iv;
        u32 iv[AES_BLOCK_SIZE / 4];

        dev_dbg(device_data->dev, "[%s]", __func__);

        /*
         * Since we loop on num_of_regs we need to have a check in case
         * someone provides an incorrect blocksize which would force calling
         * cfg_iv with i greater than 2 which is an error.
         */
        if (num_of_regs > 2) {
                dev_err(device_data->dev, "[%s] Incorrect blocksize %d",
                        __func__, ctx->blocksize);
                return -EINVAL;
        }

        for (i = 0; i < ctx->blocksize / 4; i++)
                iv[i] = be32_to_cpup(civ + i);

        for (i = 0; i < num_of_regs; i++) {
                status = cfg_iv(device_data, iv[i*2], iv[i*2+1],
                                (enum cryp_init_vector_index) i);
                if (status != 0)
                        return status;
        }
        return status;
}

static int set_key(struct cryp_device_data *device_data,
                   u32 left_key,
                   u32 right_key,
                   enum cryp_key_reg_index index)
{
        struct cryp_key_value key_value;
        int cryp_error;

        dev_dbg(device_data->dev, "[%s]", __func__);

        key_value.key_value_left = left_key;
        key_value.key_value_right = right_key;

        cryp_error = cryp_configure_key_values(device_data,
                                               index,
                                               key_value);
        if (cryp_error != 0)
                dev_err(device_data->dev, "[%s]: "
                        "cryp_configure_key_values() failed!", __func__);

        return cryp_error;
}

static int cfg_keys(struct cryp_ctx *ctx)
{
        int i;
        int num_of_regs = ctx->keylen / 8;
        u32 swapped_key[CRYP_MAX_KEY_SIZE / 4];
        __be32 *ckey = (__be32 *)ctx->key;
        int cryp_error = 0;

        dev_dbg(ctx->device->dev, "[%s]", __func__);

        if (mode_is_aes(ctx->config.algomode)) {
                swap_words_in_key_and_bits_in_byte((u8 *)ckey,
                                                   (u8 *)swapped_key,
                                                   ctx->keylen);
        } else {
                for (i = 0; i < ctx->keylen / 4; i++)
                        swapped_key[i] = be32_to_cpup(ckey + i);
        }

        for (i = 0; i < num_of_regs; i++) {
                cryp_error = set_key(ctx->device,
                                     swapped_key[i * 2],
                                     swapped_key[i * 2 + 1],
                                     (enum cryp_key_reg_index) i);

                if (cryp_error != 0) {
                        dev_err(ctx->device->dev, "[%s]: set_key() failed!",
                                        __func__);
                        return cryp_error;
                }
        }
        return cryp_error;
}

static int cryp_setup_context(struct cryp_ctx *ctx,
                              struct cryp_device_data *device_data)
{
        u32 control_register = CRYP_CR_DEFAULT;

        switch (cryp_mode) {
        case CRYP_MODE_INTERRUPT:
                writel_relaxed(CRYP_IMSC_DEFAULT, &device_data->base->imsc);
                break;

        case CRYP_MODE_DMA:
                writel_relaxed(CRYP_DMACR_DEFAULT, &device_data->base->dmacr);
                break;

        default:
                break;
        }

        if (ctx->updated == 0) {
                cryp_flush_inoutfifo(device_data);
                if (cfg_keys(ctx) != 0) {
                        dev_err(ctx->device->dev, "[%s]: cfg_keys failed!",
                                __func__);
                        return -EINVAL;
                }

                if (ctx->iv &&
                    CRYP_ALGO_AES_ECB != ctx->config.algomode &&
                    CRYP_ALGO_DES_ECB != ctx->config.algomode &&
                    CRYP_ALGO_TDES_ECB != ctx->config.algomode) {
                        if (cfg_ivs(device_data, ctx) != 0)
                                return -EPERM;
                }

                cryp_set_configuration(device_data, &ctx->config,
                                       &control_register);
                add_session_id(ctx);
        } else if (ctx->updated == 1 &&
                   ctx->session_id != atomic_read(&session_id)) {
                cryp_flush_inoutfifo(device_data);
                cryp_restore_device_context(device_data, &ctx->dev_ctx);

                add_session_id(ctx);
                control_register = ctx->dev_ctx.cr;
        } else
                control_register = ctx->dev_ctx.cr;

        writel(control_register |
               (CRYP_CRYPEN_ENABLE << CRYP_CR_CRYPEN_POS),
               &device_data->base->cr);

        return 0;
}

static int cryp_get_device_data(struct cryp_ctx *ctx,
                                struct cryp_device_data **device_data)
{
        int ret;
        struct klist_iter device_iterator;
        struct klist_node *device_node;
        struct cryp_device_data *local_device_data = NULL;
        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        /* Wait until a device is available */
        ret = down_interruptible(&driver_data.device_allocation);
        if (ret)
                return ret;  /* Interrupted */

        /* Select a device */
        klist_iter_init(&driver_data.device_list, &device_iterator);

        device_node = klist_next(&device_iterator);
        while (device_node) {
                local_device_data = container_of(device_node,
                                           struct cryp_device_data, list_node);
                spin_lock(&local_device_data->ctx_lock);
                /* current_ctx allocates a device, NULL = unallocated */
                if (local_device_data->current_ctx) {
                        device_node = klist_next(&device_iterator);
                } else {
                        local_device_data->current_ctx = ctx;
                        ctx->device = local_device_data;
                        spin_unlock(&local_device_data->ctx_lock);
                        break;
                }
                spin_unlock(&local_device_data->ctx_lock);
        }
        klist_iter_exit(&device_iterator);

        if (!device_node) {
                /**
                 * No free device found.
                 * Since we allocated a device with down_interruptible, this
                 * should not be able to happen.
                 * Number of available devices, which are contained in
                 * device_allocation, is therefore decremented by not doing
                 * an up(device_allocation).
                 */
                return -EBUSY;
        }

        *device_data = local_device_data;

        return 0;
}

static void cryp_dma_setup_channel(struct cryp_device_data *device_data,
                                   struct device *dev)
{
        struct dma_slave_config mem2cryp = {
                .direction = DMA_MEM_TO_DEV,
                .dst_addr = device_data->phybase + CRYP_DMA_TX_FIFO,
                .dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
                .dst_maxburst = 4,
        };
        struct dma_slave_config cryp2mem = {
                .direction = DMA_DEV_TO_MEM,
                .src_addr = device_data->phybase + CRYP_DMA_RX_FIFO,
                .src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES,
                .src_maxburst = 4,
        };

        dma_cap_zero(device_data->dma.mask);
        dma_cap_set(DMA_SLAVE, device_data->dma.mask);

        device_data->dma.cfg_mem2cryp = mem_to_engine;
        device_data->dma.chan_mem2cryp =
                dma_request_channel(device_data->dma.mask,
                                    stedma40_filter,
                                    device_data->dma.cfg_mem2cryp);

        device_data->dma.cfg_cryp2mem = engine_to_mem;
        device_data->dma.chan_cryp2mem =
                dma_request_channel(device_data->dma.mask,
                                    stedma40_filter,
                                    device_data->dma.cfg_cryp2mem);

        dmaengine_slave_config(device_data->dma.chan_mem2cryp, &mem2cryp);
        dmaengine_slave_config(device_data->dma.chan_cryp2mem, &cryp2mem);

        init_completion(&device_data->dma.cryp_dma_complete);
}

static void cryp_dma_out_callback(void *data)
{
        struct cryp_ctx *ctx = (struct cryp_ctx *) data;
        dev_dbg(ctx->device->dev, "[%s]: ", __func__);

        complete(&ctx->device->dma.cryp_dma_complete);
}

static int cryp_set_dma_transfer(struct cryp_ctx *ctx,
                                 struct scatterlist *sg,
                                 int len,
                                 enum dma_data_direction direction)
{
        struct dma_async_tx_descriptor *desc;
        struct dma_chan *channel = NULL;
        dma_cookie_t cookie;

        dev_dbg(ctx->device->dev, "[%s]: ", __func__);

        if (unlikely(!IS_ALIGNED((unsigned long)sg, 4))) {
                dev_err(ctx->device->dev, "[%s]: Data in sg list isn't "
                        "aligned! Addr: 0x%08lx", __func__, (unsigned long)sg);
                return -EFAULT;
        }

        switch (direction) {
        case DMA_TO_DEVICE:
                channel = ctx->device->dma.chan_mem2cryp;
                ctx->device->dma.sg_src = sg;
                ctx->device->dma.sg_src_len = dma_map_sg(channel->device->dev,
                                                 ctx->device->dma.sg_src,
                                                 ctx->device->dma.nents_src,
                                                 direction);

                if (!ctx->device->dma.sg_src_len) {
                        dev_dbg(ctx->device->dev,
                                "[%s]: Could not map the sg list (TO_DEVICE)",
                                __func__);
                        return -EFAULT;
                }

                dev_dbg(ctx->device->dev, "[%s]: Setting up DMA for buffer "
                        "(TO_DEVICE)", __func__);

                desc = dmaengine_prep_slave_sg(channel,
                                ctx->device->dma.sg_src,
                                ctx->device->dma.sg_src_len,
                                DMA_MEM_TO_DEV, DMA_CTRL_ACK);
                break;

        case DMA_FROM_DEVICE:
                channel = ctx->device->dma.chan_cryp2mem;
                ctx->device->dma.sg_dst = sg;
                ctx->device->dma.sg_dst_len = dma_map_sg(channel->device->dev,
                                                 ctx->device->dma.sg_dst,
                                                 ctx->device->dma.nents_dst,
                                                 direction);

                if (!ctx->device->dma.sg_dst_len) {
                        dev_dbg(ctx->device->dev,
                                "[%s]: Could not map the sg list (FROM_DEVICE)",
                                __func__);
                        return -EFAULT;
                }

                dev_dbg(ctx->device->dev, "[%s]: Setting up DMA for buffer "
                        "(FROM_DEVICE)", __func__);

                desc = dmaengine_prep_slave_sg(channel,
                                ctx->device->dma.sg_dst,
                                ctx->device->dma.sg_dst_len,
                                DMA_DEV_TO_MEM,
                                DMA_CTRL_ACK |
                                DMA_PREP_INTERRUPT);

                desc->callback = cryp_dma_out_callback;
                desc->callback_param = ctx;
                break;

        default:
                dev_dbg(ctx->device->dev, "[%s]: Invalid DMA direction",
                        __func__);
                return -EFAULT;
        }

        cookie = dmaengine_submit(desc);
        if (dma_submit_error(cookie)) {
                dev_dbg(ctx->device->dev, "[%s]: DMA submission failed\n",
                        __func__);
                return cookie;
        }

        dma_async_issue_pending(channel);

        return 0;
}

static void cryp_dma_done(struct cryp_ctx *ctx)
{
        struct dma_chan *chan;

        dev_dbg(ctx->device->dev, "[%s]: ", __func__);

        chan = ctx->device->dma.chan_mem2cryp;
        dmaengine_terminate_all(chan);
        dma_unmap_sg(chan->device->dev, ctx->device->dma.sg_src,
                     ctx->device->dma.nents_src, DMA_TO_DEVICE);

        chan = ctx->device->dma.chan_cryp2mem;
        dmaengine_terminate_all(chan);
        dma_unmap_sg(chan->device->dev, ctx->device->dma.sg_dst,
                     ctx->device->dma.nents_dst, DMA_FROM_DEVICE);
}

static int cryp_dma_write(struct cryp_ctx *ctx, struct scatterlist *sg,
                          int len)
{
        int error = cryp_set_dma_transfer(ctx, sg, len, DMA_TO_DEVICE);
        dev_dbg(ctx->device->dev, "[%s]: ", __func__);

        if (error) {
                dev_dbg(ctx->device->dev, "[%s]: cryp_set_dma_transfer() "
                        "failed", __func__);
                return error;
        }

        return len;
}

static int cryp_dma_read(struct cryp_ctx *ctx, struct scatterlist *sg, int len)
{
        int error = cryp_set_dma_transfer(ctx, sg, len, DMA_FROM_DEVICE);
        if (error) {
                dev_dbg(ctx->device->dev, "[%s]: cryp_set_dma_transfer() "
                        "failed", __func__);
                return error;
        }

        return len;
}

static void cryp_polling_mode(struct cryp_ctx *ctx,
                              struct cryp_device_data *device_data)
{
        int len = ctx->blocksize / BYTES_PER_WORD;
        int remaining_length = ctx->datalen;
        u32 *indata = (u32 *)ctx->indata;
        u32 *outdata = (u32 *)ctx->outdata;

        while (remaining_length > 0) {
                writesl(&device_data->base->din, indata, len);
                indata += len;
                remaining_length -= (len * BYTES_PER_WORD);
                cryp_wait_until_done(device_data);

                readsl(&device_data->base->dout, outdata, len);
                outdata += len;
                cryp_wait_until_done(device_data);
        }
}

static int cryp_disable_power(struct device *dev,
                              struct cryp_device_data *device_data,
                              bool save_device_context)
{
        int ret = 0;

        dev_dbg(dev, "[%s]", __func__);

        spin_lock(&device_data->power_state_spinlock);
        if (!device_data->power_state)
                goto out;

        spin_lock(&device_data->ctx_lock);
        if (save_device_context && device_data->current_ctx) {
                cryp_save_device_context(device_data,
                                &device_data->current_ctx->dev_ctx,
                                cryp_mode);
                device_data->restore_dev_ctx = true;
        }
        spin_unlock(&device_data->ctx_lock);

        clk_disable(device_data->clk);
        ret = regulator_disable(device_data->pwr_regulator);
        if (ret)
                dev_err(dev, "[%s]: "
                                "regulator_disable() failed!",
                                __func__);

        device_data->power_state = false;

out:
        spin_unlock(&device_data->power_state_spinlock);

        return ret;
}

static int cryp_enable_power(
                struct device *dev,
                struct cryp_device_data *device_data,
                bool restore_device_context)
{
        int ret = 0;

        dev_dbg(dev, "[%s]", __func__);

        spin_lock(&device_data->power_state_spinlock);
        if (!device_data->power_state) {
                ret = regulator_enable(device_data->pwr_regulator);
                if (ret) {
                        dev_err(dev, "[%s]: regulator_enable() failed!",
                                        __func__);
                        goto out;
                }

                ret = clk_enable(device_data->clk);
                if (ret) {
                        dev_err(dev, "[%s]: clk_enable() failed!",
                                        __func__);
                        regulator_disable(device_data->pwr_regulator);
                        goto out;
                }
                device_data->power_state = true;
        }

        if (device_data->restore_dev_ctx) {
                spin_lock(&device_data->ctx_lock);
                if (restore_device_context && device_data->current_ctx) {
                        device_data->restore_dev_ctx = false;
                        cryp_restore_device_context(device_data,
                                        &device_data->current_ctx->dev_ctx);
                }
                spin_unlock(&device_data->ctx_lock);
        }
out:
        spin_unlock(&device_data->power_state_spinlock);

        return ret;
}

static int hw_crypt_noxts(struct cryp_ctx *ctx,
                          struct cryp_device_data *device_data)
{
        int ret = 0;

        const u8 *indata = ctx->indata;
        u8 *outdata = ctx->outdata;
        u32 datalen = ctx->datalen;
        u32 outlen = datalen;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        ctx->outlen = ctx->datalen;

        if (unlikely(!IS_ALIGNED((unsigned long)indata, 4))) {
                pr_debug(DEV_DBG_NAME " [%s]: Data isn't aligned! Addr: "
                         "0x%08lx", __func__, (unsigned long)indata);
                return -EINVAL;
        }

        ret = cryp_setup_context(ctx, device_data);

        if (ret)
                goto out;

        if (cryp_mode == CRYP_MODE_INTERRUPT) {
                cryp_enable_irq_src(device_data, CRYP_IRQ_SRC_INPUT_FIFO |
                                    CRYP_IRQ_SRC_OUTPUT_FIFO);

                /*
                 * ctx->outlen is decremented in the cryp_interrupt_handler
                 * function. We had to add cpu_relax() (barrier) to make sure
                 * that gcc didn't optimze away this variable.
                 */
                while (ctx->outlen > 0)
                        cpu_relax();
        } else if (cryp_mode == CRYP_MODE_POLLING ||
                   cryp_mode == CRYP_MODE_DMA) {
                /*
                 * The reason for having DMA in this if case is that if we are
                 * running cryp_mode = 2, then we separate DMA routines for
                 * handling cipher/plaintext > blocksize, except when
                 * running the normal CRYPTO_ALG_TYPE_CIPHER, then we still use
                 * the polling mode. Overhead of doing DMA setup eats up the
                 * benefits using it.
                 */
                cryp_polling_mode(ctx, device_data);
        } else {
                dev_err(ctx->device->dev, "[%s]: Invalid operation mode!",
                        __func__);
                ret = -EPERM;
                goto out;
        }

        cryp_save_device_context(device_data, &ctx->dev_ctx, cryp_mode);
        ctx->updated = 1;

out:
        ctx->indata = indata;
        ctx->outdata = outdata;
        ctx->datalen = datalen;
        ctx->outlen = outlen;

        return ret;
}

static int get_nents(struct scatterlist *sg, int nbytes)
{
        int nents = 0;

        while (nbytes > 0) {
                nbytes -= sg->length;
                sg = sg_next(sg);
                nents++;
        }

        return nents;
}

static int ablk_dma_crypt(struct skcipher_request *areq)
{
        struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(areq);
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);
        struct cryp_device_data *device_data;

        int bytes_written = 0;
        int bytes_read = 0;
        int ret;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        ctx->datalen = areq->cryptlen;
        ctx->outlen = areq->cryptlen;

        ret = cryp_get_device_data(ctx, &device_data);
        if (ret)
                return ret;

        ret = cryp_setup_context(ctx, device_data);
        if (ret)
                goto out;

        /* We have the device now, so store the nents in the dma struct. */
        ctx->device->dma.nents_src = get_nents(areq->src, ctx->datalen);
        ctx->device->dma.nents_dst = get_nents(areq->dst, ctx->outlen);

        /* Enable DMA in- and output. */
        cryp_configure_for_dma(device_data, CRYP_DMA_ENABLE_BOTH_DIRECTIONS);

        bytes_written = cryp_dma_write(ctx, areq->src, ctx->datalen);
        bytes_read = cryp_dma_read(ctx, areq->dst, bytes_written);

        wait_for_completion(&ctx->device->dma.cryp_dma_complete);
        cryp_dma_done(ctx);

        cryp_save_device_context(device_data, &ctx->dev_ctx, cryp_mode);
        ctx->updated = 1;

out:
        spin_lock(&device_data->ctx_lock);
        device_data->current_ctx = NULL;
        ctx->device = NULL;
        spin_unlock(&device_data->ctx_lock);

        /*
         * The down_interruptible part for this semaphore is called in
         * cryp_get_device_data.
         */
        up(&driver_data.device_allocation);

        if (unlikely(bytes_written != bytes_read))
                return -EPERM;

        return 0;
}

static int ablk_crypt(struct skcipher_request *areq)
{
        struct skcipher_walk walk;
        struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(areq);
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);
        struct cryp_device_data *device_data;
        unsigned long src_paddr;
        unsigned long dst_paddr;
        int ret;
        int nbytes;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        ret = cryp_get_device_data(ctx, &device_data);
        if (ret)
                goto out;

        ret = skcipher_walk_async(&walk, areq);

        if (ret) {
                pr_err(DEV_DBG_NAME "[%s]: skcipher_walk_async() failed!",
                        __func__);
                goto out;
        }

        while ((nbytes = walk.nbytes) > 0) {
                ctx->iv = walk.iv;
                src_paddr = (page_to_phys(walk.src.phys.page) + walk.src.phys.offset);
                ctx->indata = phys_to_virt(src_paddr);

                dst_paddr = (page_to_phys(walk.dst.phys.page) + walk.dst.phys.offset);
                ctx->outdata = phys_to_virt(dst_paddr);

                ctx->datalen = nbytes - (nbytes % ctx->blocksize);

                ret = hw_crypt_noxts(ctx, device_data);
                if (ret)
                        goto out;

                nbytes -= ctx->datalen;
                ret = skcipher_walk_done(&walk, nbytes);
                if (ret)
                        goto out;
        }

out:
        /* Release the device */
        spin_lock(&device_data->ctx_lock);
        device_data->current_ctx = NULL;
        ctx->device = NULL;
        spin_unlock(&device_data->ctx_lock);

        /*
         * The down_interruptible part for this semaphore is called in
         * cryp_get_device_data.
         */
        up(&driver_data.device_allocation);

        return ret;
}

static int aes_skcipher_setkey(struct crypto_skcipher *cipher,
                                 const u8 *key, unsigned int keylen)
{
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        switch (keylen) {
        case AES_KEYSIZE_128:
                ctx->config.keysize = CRYP_KEY_SIZE_128;
                break;

        case AES_KEYSIZE_192:
                ctx->config.keysize = CRYP_KEY_SIZE_192;
                break;

        case AES_KEYSIZE_256:
                ctx->config.keysize = CRYP_KEY_SIZE_256;
                break;

        default:
                pr_err(DEV_DBG_NAME "[%s]: Unknown keylen!", __func__);
                return -EINVAL;
        }

        memcpy(ctx->key, key, keylen);
        ctx->keylen = keylen;

        ctx->updated = 0;

        return 0;
}

static int des_skcipher_setkey(struct crypto_skcipher *cipher,
                                 const u8 *key, unsigned int keylen)
{
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);
        int err;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        err = verify_skcipher_des_key(cipher, key);
        if (err)
                return err;

        memcpy(ctx->key, key, keylen);
        ctx->keylen = keylen;

        ctx->updated = 0;
        return 0;
}

static int des3_skcipher_setkey(struct crypto_skcipher *cipher,
                                  const u8 *key, unsigned int keylen)
{
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);
        int err;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        err = verify_skcipher_des3_key(cipher, key);
        if (err)
                return err;

        memcpy(ctx->key, key, keylen);
        ctx->keylen = keylen;

        ctx->updated = 0;
        return 0;
}

static int cryp_blk_encrypt(struct skcipher_request *areq)
{
        struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(areq);
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        ctx->config.algodir = CRYP_ALGORITHM_ENCRYPT;

        /*
         * DMA does not work for DES due to a hw bug */
        if (cryp_mode == CRYP_MODE_DMA && mode_is_aes(ctx->config.algomode))
                return ablk_dma_crypt(areq);

        /* For everything except DMA, we run the non DMA version. */
        return ablk_crypt(areq);
}

static int cryp_blk_decrypt(struct skcipher_request *areq)
{
        struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(areq);
        struct cryp_ctx *ctx = crypto_skcipher_ctx(cipher);

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        ctx->config.algodir = CRYP_ALGORITHM_DECRYPT;

        /* DMA does not work for DES due to a hw bug */
        if (cryp_mode == CRYP_MODE_DMA && mode_is_aes(ctx->config.algomode))
                return ablk_dma_crypt(areq);

        /* For everything except DMA, we run the non DMA version. */
        return ablk_crypt(areq);
}

struct cryp_algo_template {
        enum cryp_algo_mode algomode;
        struct skcipher_alg skcipher;
};

static int cryp_init_tfm(struct crypto_skcipher *tfm)
{
        struct cryp_ctx *ctx = crypto_skcipher_ctx(tfm);
        struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
        struct cryp_algo_template *cryp_alg = container_of(alg,
                        struct cryp_algo_template,
                        skcipher);

        ctx->config.algomode = cryp_alg->algomode;
        ctx->blocksize = crypto_skcipher_blocksize(tfm);

        return 0;
}

static struct cryp_algo_template cryp_algs[] = {
        {
                .algomode = CRYP_ALGO_AES_ECB,
                .skcipher = {
                        .base.cra_name          = "ecb(aes)",
                        .base.cra_driver_name   = "ecb-aes-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = AES_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = AES_MIN_KEY_SIZE,
                        .max_keysize            = AES_MAX_KEY_SIZE,
                        .setkey                 = aes_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .init                   = cryp_init_tfm,
                }
        },
        {
                .algomode = CRYP_ALGO_AES_CBC,
                .skcipher = {
                        .base.cra_name          = "cbc(aes)",
                        .base.cra_driver_name   = "cbc-aes-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = AES_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = AES_MIN_KEY_SIZE,
                        .max_keysize            = AES_MAX_KEY_SIZE,
                        .setkey                 = aes_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .init                   = cryp_init_tfm,
                        .ivsize                 = AES_BLOCK_SIZE,
                }
        },
        {
                .algomode = CRYP_ALGO_AES_CTR,
                .skcipher = {
                        .base.cra_name          = "ctr(aes)",
                        .base.cra_driver_name   = "ctr-aes-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = 1,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = AES_MIN_KEY_SIZE,
                        .max_keysize            = AES_MAX_KEY_SIZE,
                        .setkey                 = aes_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .init                   = cryp_init_tfm,
                        .ivsize                 = AES_BLOCK_SIZE,
                        .chunksize              = AES_BLOCK_SIZE,
                }
        },
        {
                .algomode = CRYP_ALGO_DES_ECB,
                .skcipher = {
                        .base.cra_name          = "ecb(des)",
                        .base.cra_driver_name   = "ecb-des-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = DES_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = DES_KEY_SIZE,
                        .max_keysize            = DES_KEY_SIZE,
                        .setkey                 = des_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .init                   = cryp_init_tfm,
                }
        },
        {
                .algomode = CRYP_ALGO_TDES_ECB,
                .skcipher = {
                        .base.cra_name          = "ecb(des3_ede)",
                        .base.cra_driver_name   = "ecb-des3_ede-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = DES3_EDE_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = DES3_EDE_KEY_SIZE,
                        .max_keysize            = DES3_EDE_KEY_SIZE,
                        .setkey                 = des3_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .init                   = cryp_init_tfm,
                }
        },
        {
                .algomode = CRYP_ALGO_DES_CBC,
                .skcipher = {
                        .base.cra_name          = "cbc(des)",
                        .base.cra_driver_name   = "cbc-des-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = DES_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = DES_KEY_SIZE,
                        .max_keysize            = DES_KEY_SIZE,
                        .setkey                 = des_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .ivsize                 = DES_BLOCK_SIZE,
                        .init                   = cryp_init_tfm,
                }
        },
        {
                .algomode = CRYP_ALGO_TDES_CBC,
                .skcipher = {
                        .base.cra_name          = "cbc(des3_ede)",
                        .base.cra_driver_name   = "cbc-des3_ede-ux500",
                        .base.cra_priority      = 300,
                        .base.cra_flags         = CRYPTO_ALG_ASYNC,
                        .base.cra_blocksize     = DES3_EDE_BLOCK_SIZE,
                        .base.cra_ctxsize       = sizeof(struct cryp_ctx),
                        .base.cra_alignmask     = 3,
                        .base.cra_module        = THIS_MODULE,

                        .min_keysize            = DES3_EDE_KEY_SIZE,
                        .max_keysize            = DES3_EDE_KEY_SIZE,
                        .setkey                 = des3_skcipher_setkey,
                        .encrypt                = cryp_blk_encrypt,
                        .decrypt                = cryp_blk_decrypt,
                        .ivsize                 = DES3_EDE_BLOCK_SIZE,
                        .init                   = cryp_init_tfm,
                }
        }
};

/**
 * cryp_algs_register_all -
 */
static int cryp_algs_register_all(void)
{
        int ret;
        int i;
        int count;

        pr_debug("[%s]", __func__);

        for (i = 0; i < ARRAY_SIZE(cryp_algs); i++) {
                ret = crypto_register_skcipher(&cryp_algs[i].skcipher);
                if (ret) {
                        count = i;
                        pr_err("[%s] alg registration failed",
                                        cryp_algs[i].skcipher.base.cra_driver_name);
                        goto unreg;
                }
        }
        return 0;
unreg:
        for (i = 0; i < count; i++)
                crypto_unregister_skcipher(&cryp_algs[i].skcipher);
        return ret;
}

/**
 * cryp_algs_unregister_all -
 */
static void cryp_algs_unregister_all(void)
{
        int i;

        pr_debug(DEV_DBG_NAME " [%s]", __func__);

        for (i = 0; i < ARRAY_SIZE(cryp_algs); i++)
                crypto_unregister_skcipher(&cryp_algs[i].skcipher);
}

static int ux500_cryp_probe(struct platform_device *pdev)
{
        int ret;
        struct resource *res;
        struct resource *res_irq;
        struct cryp_device_data *device_data;
        struct cryp_protection_config prot = {
                .privilege_access = CRYP_STATE_ENABLE
        };
        struct device *dev = &pdev->dev;

        dev_dbg(dev, "[%s]", __func__);
        device_data = devm_kzalloc(dev, sizeof(*device_data), GFP_ATOMIC);
        if (!device_data) {
                ret = -ENOMEM;
                goto out;
        }

        device_data->dev = dev;
        device_data->current_ctx = NULL;

        /* Grab the DMA configuration from platform data. */
        mem_to_engine = &((struct cryp_platform_data *)
                         dev->platform_data)->mem_to_engine;
        engine_to_mem = &((struct cryp_platform_data *)
                         dev->platform_data)->engine_to_mem;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res) {
                dev_err(dev, "[%s]: platform_get_resource() failed",
                                __func__);
                ret = -ENODEV;
                goto out;
        }

        device_data->phybase = res->start;
        device_data->base = devm_ioremap_resource(dev, res);
        if (IS_ERR(device_data->base)) {
                ret = PTR_ERR(device_data->base);
                goto out;
        }

        spin_lock_init(&device_data->ctx_lock);
        spin_lock_init(&device_data->power_state_spinlock);

        /* Enable power for CRYP hardware block */
        device_data->pwr_regulator = regulator_get(&pdev->dev, "v-ape");
        if (IS_ERR(device_data->pwr_regulator)) {
                dev_err(dev, "[%s]: could not get cryp regulator", __func__);
                ret = PTR_ERR(device_data->pwr_regulator);
                device_data->pwr_regulator = NULL;
                goto out;
        }

        /* Enable the clk for CRYP hardware block */
        device_data->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(device_data->clk)) {
                dev_err(dev, "[%s]: clk_get() failed!", __func__);
                ret = PTR_ERR(device_data->clk);
                goto out_regulator;
        }

        ret = clk_prepare(device_data->clk);
        if (ret) {
                dev_err(dev, "[%s]: clk_prepare() failed!", __func__);
                goto out_regulator;
        }

        /* Enable device power (and clock) */
        ret = cryp_enable_power(device_data->dev, device_data, false);
        if (ret) {
                dev_err(dev, "[%s]: cryp_enable_power() failed!", __func__);
                goto out_clk_unprepare;
        }

        if (cryp_check(device_data)) {
                dev_err(dev, "[%s]: cryp_check() failed!", __func__);
                ret = -EINVAL;
                goto out_power;
        }

        if (cryp_configure_protection(device_data, &prot)) {
                dev_err(dev, "[%s]: cryp_configure_protection() failed!",
                        __func__);
                ret = -EINVAL;
                goto out_power;
        }

        res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        if (!res_irq) {
                dev_err(dev, "[%s]: IORESOURCE_IRQ unavailable",
                        __func__);
                ret = -ENODEV;
                goto out_power;
        }

        ret = devm_request_irq(&pdev->dev, res_irq->start,
                               cryp_interrupt_handler, 0, "cryp1", device_data);
        if (ret) {
                dev_err(dev, "[%s]: Unable to request IRQ", __func__);
                goto out_power;
        }

        if (cryp_mode == CRYP_MODE_DMA)
                cryp_dma_setup_channel(device_data, dev);

        platform_set_drvdata(pdev, device_data);

        /* Put the new device into the device list... */
        klist_add_tail(&device_data->list_node, &driver_data.device_list);

        /* ... and signal that a new device is available. */
        up(&driver_data.device_allocation);

        atomic_set(&session_id, 1);

        ret = cryp_algs_register_all();
        if (ret) {
                dev_err(dev, "[%s]: cryp_algs_register_all() failed!",
                        __func__);
                goto out_power;
        }

        dev_info(dev, "successfully registered\n");

        return 0;

out_power:
        cryp_disable_power(device_data->dev, device_data, false);

out_clk_unprepare:
        clk_unprepare(device_data->clk);

out_regulator:
        regulator_put(device_data->pwr_regulator);

out:
        return ret;
}

static int ux500_cryp_remove(struct platform_device *pdev)
{
        struct cryp_device_data *device_data;

        dev_dbg(&pdev->dev, "[%s]", __func__);
        device_data = platform_get_drvdata(pdev);
        if (!device_data) {
                dev_err(&pdev->dev, "[%s]: platform_get_drvdata() failed!",
                        __func__);
                return -ENOMEM;
        }

        /* Try to decrease the number of available devices. */
        if (down_trylock(&driver_data.device_allocation))
                return -EBUSY;

        /* Check that the device is free */
        spin_lock(&device_data->ctx_lock);
        /* current_ctx allocates a device, NULL = unallocated */
        if (device_data->current_ctx) {
                /* The device is busy */
                spin_unlock(&device_data->ctx_lock);
                /* Return the device to the pool. */
                up(&driver_data.device_allocation);
                return -EBUSY;
        }

        spin_unlock(&device_data->ctx_lock);

        /* Remove the device from the list */
        if (klist_node_attached(&device_data->list_node))
                klist_remove(&device_data->list_node);

        /* If this was the last device, remove the services */
        if (list_empty(&driver_data.device_list.k_list))
                cryp_algs_unregister_all();

        if (cryp_disable_power(&pdev->dev, device_data, false))
                dev_err(&pdev->dev, "[%s]: cryp_disable_power() failed",
                        __func__);

        clk_unprepare(device_data->clk);
        regulator_put(device_data->pwr_regulator);

        return 0;
}

static void ux500_cryp_shutdown(struct platform_device *pdev)
{
        struct cryp_device_data *device_data;

        dev_dbg(&pdev->dev, "[%s]", __func__);

        device_data = platform_get_drvdata(pdev);
        if (!device_data) {
                dev_err(&pdev->dev, "[%s]: platform_get_drvdata() failed!",
                        __func__);
                return;
        }

        /* Check that the device is free */
        spin_lock(&device_data->ctx_lock);
        /* current_ctx allocates a device, NULL = unallocated */
        if (!device_data->current_ctx) {
                if (down_trylock(&driver_data.device_allocation))
                        dev_dbg(&pdev->dev, "[%s]: Cryp still in use!"
                                "Shutting down anyway...", __func__);
                /**
                 * (Allocate the device)
                 * Need to set this to non-null (dummy) value,
                 * to avoid usage if context switching.
                 */
                device_data->current_ctx++;
        }
        spin_unlock(&device_data->ctx_lock);

        /* Remove the device from the list */
        if (klist_node_attached(&device_data->list_node))
                klist_remove(&device_data->list_node);

        /* If this was the last device, remove the services */
        if (list_empty(&driver_data.device_list.k_list))
                cryp_algs_unregister_all();

        if (cryp_disable_power(&pdev->dev, device_data, false))
                dev_err(&pdev->dev, "[%s]: cryp_disable_power() failed",
                        __func__);

}

#ifdef CONFIG_PM_SLEEP
static int ux500_cryp_suspend(struct device *dev)
{
        int ret;
        struct platform_device *pdev = to_platform_device(dev);
        struct cryp_device_data *device_data;
        struct resource *res_irq;
        struct cryp_ctx *temp_ctx = NULL;

        dev_dbg(dev, "[%s]", __func__);

        /* Handle state? */
        device_data = platform_get_drvdata(pdev);
        if (!device_data) {
                dev_err(dev, "[%s]: platform_get_drvdata() failed!", __func__);
                return -ENOMEM;
        }

        res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
        if (!res_irq)
                dev_err(dev, "[%s]: IORESOURCE_IRQ, unavailable", __func__);
        else
                disable_irq(res_irq->start);

        spin_lock(&device_data->ctx_lock);
        if (!device_data->current_ctx)
                device_data->current_ctx++;
        spin_unlock(&device_data->ctx_lock);

        if (device_data->current_ctx == ++temp_ctx) {
                if (down_interruptible(&driver_data.device_allocation))
                        dev_dbg(dev, "[%s]: down_interruptible() failed",
                                __func__);
                ret = cryp_disable_power(dev, device_data, false);

        } else
                ret = cryp_disable_power(dev, device_data, true);

        if (ret)
                dev_err(dev, "[%s]: cryp_disable_power()", __func__);

        return ret;
}

static int ux500_cryp_resume(struct device *dev)
{
        int ret = 0;
        struct platform_device *pdev = to_platform_device(dev);
        struct cryp_device_data *device_data;
        struct resource *res_irq;
        struct cryp_ctx *temp_ctx = NULL;

        dev_dbg(dev, "[%s]", __func__);

        device_data = platform_get_drvdata(pdev);
        if (!device_data) {
                dev_err(dev, "[%s]: platform_get_drvdata() failed!", __func__);
                return -ENOMEM;
        }

        spin_lock(&device_data->ctx_lock);
        if (device_data->current_ctx == ++temp_ctx)
                device_data->current_ctx = NULL;
        spin_unlock(&device_data->ctx_lock);


        if (!device_data->current_ctx)
                up(&driver_data.device_allocation);
        else
                ret = cryp_enable_power(dev, device_data, true);

        if (ret)
                dev_err(dev, "[%s]: cryp_enable_power() failed!", __func__);
        else {
                res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
                if (res_irq)
                        enable_irq(res_irq->start);
        }

        return ret;
}
#endif

static SIMPLE_DEV_PM_OPS(ux500_cryp_pm, ux500_cryp_suspend, ux500_cryp_resume);

static const struct of_device_id ux500_cryp_match[] = {
        { .compatible = "stericsson,ux500-cryp" },
        { },
};
MODULE_DEVICE_TABLE(of, ux500_cryp_match);

static struct platform_driver cryp_driver = {
        .probe  = ux500_cryp_probe,
        .remove = ux500_cryp_remove,
        .shutdown = ux500_cryp_shutdown,
        .driver = {
                .name  = "cryp1",
                .of_match_table = ux500_cryp_match,
                .pm    = &ux500_cryp_pm,
        }
};

static int __init ux500_cryp_mod_init(void)
{
        pr_debug("[%s] is called!", __func__);
        klist_init(&driver_data.device_list, NULL, NULL);
        /* Initialize the semaphore to 0 devices (locked state) */
        sema_init(&driver_data.device_allocation, 0);
        return platform_driver_register(&cryp_driver);
}

static void __exit ux500_cryp_mod_fini(void)
{
        pr_debug("[%s] is called!", __func__);
        platform_driver_unregister(&cryp_driver);
}

module_init(ux500_cryp_mod_init);
module_exit(ux500_cryp_mod_fini);

module_param(cryp_mode, int, 0);

MODULE_DESCRIPTION("Driver for ST-Ericsson UX500 CRYP crypto engine.");
MODULE_ALIAS_CRYPTO("aes-all");
MODULE_ALIAS_CRYPTO("des-all");

MODULE_LICENSE("GPL");