hfs: get rid of hfs_sync_super

[linux/fpc-iii.git] / drivers / nfc / pn544_hci.c

/*
 * HCI based Driver for NXP PN544 NFC Chip
 *
 * Copyright (C) 2012  Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <linux/crc-ccitt.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/miscdevice.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/i2c.h>

#include <linux/nfc.h>
#include <net/nfc/hci.h>
#include <net/nfc/shdlc.h>

#include <linux/nfc/pn544.h>

#define DRIVER_DESC "HCI NFC driver for PN544"

#define PN544_HCI_DRIVER_NAME "pn544_hci"

/* Timing restrictions (ms) */
#define PN544_HCI_RESETVEN_TIME         30

static struct i2c_device_id pn544_hci_id_table[] = {
        {"pn544", 0},
        {}
};

MODULE_DEVICE_TABLE(i2c, pn544_hci_id_table);

#define HCI_MODE 0
#define FW_MODE 1

/* framing in HCI mode */
#define PN544_HCI_LLC_LEN               1
#define PN544_HCI_LLC_CRC               2
#define PN544_HCI_LLC_LEN_CRC           (PN544_HCI_LLC_LEN + PN544_HCI_LLC_CRC)
#define PN544_HCI_LLC_MIN_SIZE          (1 + PN544_HCI_LLC_LEN_CRC)
#define PN544_HCI_LLC_MAX_PAYLOAD       29
#define PN544_HCI_LLC_MAX_SIZE          (PN544_HCI_LLC_LEN_CRC + 1 + \
                                         PN544_HCI_LLC_MAX_PAYLOAD)

enum pn544_state {
        PN544_ST_COLD,
        PN544_ST_FW_READY,
        PN544_ST_READY,
};

#define FULL_VERSION_LEN 11

/* Proprietary commands */
#define PN544_WRITE             0x3f

/* Proprietary gates, events, commands and registers */

/* NFC_HCI_RF_READER_A_GATE additional registers and commands */
#define PN544_RF_READER_A_AUTO_ACTIVATION                       0x10
#define PN544_RF_READER_A_CMD_CONTINUE_ACTIVATION               0x12
#define PN544_MIFARE_CMD                                        0x21

/* Commands that apply to all RF readers */
#define PN544_RF_READER_CMD_PRESENCE_CHECK      0x30
#define PN544_RF_READER_CMD_ACTIVATE_NEXT       0x32

/* NFC_HCI_ID_MGMT_GATE additional registers */
#define PN544_ID_MGMT_FULL_VERSION_SW           0x10

#define PN544_RF_READER_ISO15693_GATE           0x12

#define PN544_RF_READER_F_GATE                  0x14
#define PN544_FELICA_ID                         0x04
#define PN544_FELICA_RAW                        0x20

#define PN544_RF_READER_JEWEL_GATE              0x15
#define PN544_JEWEL_RAW_CMD                     0x23

#define PN544_RF_READER_NFCIP1_INITIATOR_GATE   0x30
#define PN544_RF_READER_NFCIP1_TARGET_GATE      0x31

#define PN544_SYS_MGMT_GATE                     0x90
#define PN544_SYS_MGMT_INFO_NOTIFICATION        0x02

#define PN544_POLLING_LOOP_MGMT_GATE            0x94
#define PN544_PL_RDPHASES                       0x06
#define PN544_PL_EMULATION                      0x07
#define PN544_PL_NFCT_DEACTIVATED               0x09

#define PN544_SWP_MGMT_GATE                     0xA0

#define PN544_NFC_WI_MGMT_GATE                  0xA1

static u8 pn544_custom_gates[] = {
        PN544_SYS_MGMT_GATE,
        PN544_SWP_MGMT_GATE,
        PN544_POLLING_LOOP_MGMT_GATE,
        PN544_NFC_WI_MGMT_GATE,
        PN544_RF_READER_F_GATE,
        PN544_RF_READER_JEWEL_GATE,
        PN544_RF_READER_ISO15693_GATE,
        PN544_RF_READER_NFCIP1_INITIATOR_GATE,
        PN544_RF_READER_NFCIP1_TARGET_GATE
};

/* Largest headroom needed for outgoing custom commands */
#define PN544_CMDS_HEADROOM     2

struct pn544_hci_info {
        struct i2c_client *i2c_dev;
        struct nfc_shdlc *shdlc;

        enum pn544_state state;

        struct mutex info_lock;

        unsigned int gpio_en;
        unsigned int gpio_irq;
        unsigned int gpio_fw;
        unsigned int en_polarity;

        int hard_fault;         /*
                                 * < 0 if hardware error occured (e.g. i2c err)
                                 * and prevents normal operation.
                                 */
};

static void pn544_hci_platform_init(struct pn544_hci_info *info)
{
        int polarity, retry, ret;
        char rset_cmd[] = { 0x05, 0xF9, 0x04, 0x00, 0xC3, 0xE5 };
        int count = sizeof(rset_cmd);

        pr_info(DRIVER_DESC ": %s\n", __func__);
        dev_info(&info->i2c_dev->dev, "Detecting nfc_en polarity\n");

        /* Disable fw download */
        gpio_set_value(info->gpio_fw, 0);

        for (polarity = 0; polarity < 2; polarity++) {
                info->en_polarity = polarity;
                retry = 3;
                while (retry--) {
                        /* power off */
                        gpio_set_value(info->gpio_en, !info->en_polarity);
                        usleep_range(10000, 15000);

                        /* power on */
                        gpio_set_value(info->gpio_en, info->en_polarity);
                        usleep_range(10000, 15000);

                        /* send reset */
                        dev_dbg(&info->i2c_dev->dev, "Sending reset cmd\n");
                        ret = i2c_master_send(info->i2c_dev, rset_cmd, count);
                        if (ret == count) {
                                dev_info(&info->i2c_dev->dev,
                                         "nfc_en polarity : active %s\n",
                                         (polarity == 0 ? "low" : "high"));
                                goto out;
                        }
                }
        }

        dev_err(&info->i2c_dev->dev,
                "Could not detect nfc_en polarity, fallback to active high\n");

out:
        gpio_set_value(info->gpio_en, !info->en_polarity);
}

static int pn544_hci_enable(struct pn544_hci_info *info, int mode)
{
        pr_info(DRIVER_DESC ": %s\n", __func__);

        gpio_set_value(info->gpio_fw, 0);
        gpio_set_value(info->gpio_en, info->en_polarity);
        usleep_range(10000, 15000);

        return 0;
}

static void pn544_hci_disable(struct pn544_hci_info *info)
{
        pr_info(DRIVER_DESC ": %s\n", __func__);

        gpio_set_value(info->gpio_fw, 0);
        gpio_set_value(info->gpio_en, !info->en_polarity);
        usleep_range(10000, 15000);

        gpio_set_value(info->gpio_en, info->en_polarity);
        usleep_range(10000, 15000);

        gpio_set_value(info->gpio_en, !info->en_polarity);
        usleep_range(10000, 15000);
}

static int pn544_hci_i2c_write(struct i2c_client *client, u8 *buf, int len)
{
        int r;

        usleep_range(3000, 6000);

        r = i2c_master_send(client, buf, len);

        if (r == -EREMOTEIO) {  /* Retry, chip was in standby */
                usleep_range(6000, 10000);
                r = i2c_master_send(client, buf, len);
        }

        if (r >= 0 && r != len)
                r = -EREMOTEIO;

        return r;
}

static int check_crc(u8 *buf, int buflen)
{
        int len;
        u16 crc;

        len = buf[0] + 1;
        crc = crc_ccitt(0xffff, buf, len - 2);
        crc = ~crc;

        if (buf[len - 2] != (crc & 0xff) || buf[len - 1] != (crc >> 8)) {
                pr_err(PN544_HCI_DRIVER_NAME ": CRC error 0x%x != 0x%x 0x%x\n",
                       crc, buf[len - 1], buf[len - 2]);

                pr_info(DRIVER_DESC ": %s : BAD CRC\n", __func__);
                print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE,
                               16, 2, buf, buflen, false);
                return -EPERM;
        }
        return 0;
}

/*
 * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees
 * that i2c bus will be flushed and that next read will start on a new frame.
 * returned skb contains only LLC header and payload.
 * returns:
 * -EREMOTEIO : i2c read error (fatal)
 * -EBADMSG : frame was incorrect and discarded
 * -ENOMEM : cannot allocate skb, frame dropped
 */
static int pn544_hci_i2c_read(struct i2c_client *client, struct sk_buff **skb)
{
        int r;
        u8 len;
        u8 tmp[PN544_HCI_LLC_MAX_SIZE - 1];

        r = i2c_master_recv(client, &len, 1);
        if (r != 1) {
                dev_err(&client->dev, "cannot read len byte\n");
                return -EREMOTEIO;
        }

        if ((len < (PN544_HCI_LLC_MIN_SIZE - 1)) ||
            (len > (PN544_HCI_LLC_MAX_SIZE - 1))) {
                dev_err(&client->dev, "invalid len byte\n");
                r = -EBADMSG;
                goto flush;
        }

        *skb = alloc_skb(1 + len, GFP_KERNEL);
        if (*skb == NULL) {
                r = -ENOMEM;
                goto flush;
        }

        *skb_put(*skb, 1) = len;

        r = i2c_master_recv(client, skb_put(*skb, len), len);
        if (r != len) {
                kfree_skb(*skb);
                return -EREMOTEIO;
        }

        r = check_crc((*skb)->data, (*skb)->len);
        if (r != 0) {
                kfree_skb(*skb);
                r = -EBADMSG;
                goto flush;
        }

        skb_pull(*skb, 1);
        skb_trim(*skb, (*skb)->len - 2);

        usleep_range(3000, 6000);

        return 0;

flush:
        if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0)
                r = -EREMOTEIO;

        usleep_range(3000, 6000);

        return r;
}

/*
 * Reads an shdlc frame from the chip. This is not as straightforward as it
 * seems. There are cases where we could loose the frame start synchronization.
 * The frame format is len-data-crc, and corruption can occur anywhere while
 * transiting on i2c bus, such that we could read an invalid len.
 * In order to recover synchronization with the next frame, we must be sure
 * to read the real amount of data without using the len byte. We do this by
 * assuming the following:
 * - the chip will always present only one single complete frame on the bus
 *   before triggering the interrupt
 * - the chip will not present a new frame until we have completely read
 *   the previous one (or until we have handled the interrupt).
 * The tricky case is when we read a corrupted len that is less than the real
 * len. We must detect this here in order to determine that we need to flush
 * the bus. This is the reason why we check the crc here.
 */
static irqreturn_t pn544_hci_irq_thread_fn(int irq, void *dev_id)
{
        struct pn544_hci_info *info = dev_id;
        struct i2c_client *client = info->i2c_dev;
        struct sk_buff *skb = NULL;
        int r;

        BUG_ON(!info);
        BUG_ON(irq != info->i2c_dev->irq);

        dev_dbg(&client->dev, "IRQ\n");

        if (info->hard_fault != 0)
                return IRQ_HANDLED;

        r = pn544_hci_i2c_read(client, &skb);
        if (r == -EREMOTEIO) {
                info->hard_fault = r;

                nfc_shdlc_recv_frame(info->shdlc, NULL);

                return IRQ_HANDLED;
        } else if ((r == -ENOMEM) || (r == -EBADMSG)) {
                return IRQ_HANDLED;
        }

        nfc_shdlc_recv_frame(info->shdlc, skb);

        return IRQ_HANDLED;
}

static int pn544_hci_open(struct nfc_shdlc *shdlc)
{
        struct pn544_hci_info *info = nfc_shdlc_get_clientdata(shdlc);
        int r = 0;

        mutex_lock(&info->info_lock);

        if (info->state != PN544_ST_COLD) {
                r = -EBUSY;
                goto out;
        }

        r = pn544_hci_enable(info, HCI_MODE);

out:
        mutex_unlock(&info->info_lock);
        return r;
}

static void pn544_hci_close(struct nfc_shdlc *shdlc)
{
        struct pn544_hci_info *info = nfc_shdlc_get_clientdata(shdlc);

        mutex_lock(&info->info_lock);

        if (info->state == PN544_ST_COLD)
                goto out;

        pn544_hci_disable(info);

out:
        mutex_unlock(&info->info_lock);
}

static int pn544_hci_ready(struct nfc_shdlc *shdlc)
{
        struct nfc_hci_dev *hdev = nfc_shdlc_get_hci_dev(shdlc);
        struct sk_buff *skb;
        static struct hw_config {
                u8 adr[2];
                u8 value;
        } hw_config[] = {
                {{0x9f, 0x9a}, 0x00},

                {{0x98, 0x10}, 0xbc},

                {{0x9e, 0x71}, 0x00},

                {{0x98, 0x09}, 0x00},

                {{0x9e, 0xb4}, 0x00},

                {{0x9e, 0xd9}, 0xff},
                {{0x9e, 0xda}, 0xff},
                {{0x9e, 0xdb}, 0x23},
                {{0x9e, 0xdc}, 0x21},
                {{0x9e, 0xdd}, 0x22},
                {{0x9e, 0xde}, 0x24},

                {{0x9c, 0x01}, 0x08},

                {{0x9e, 0xaa}, 0x01},

                {{0x9b, 0xd1}, 0x0d},
                {{0x9b, 0xd2}, 0x24},
                {{0x9b, 0xd3}, 0x0a},
                {{0x9b, 0xd4}, 0x22},
                {{0x9b, 0xd5}, 0x08},
                {{0x9b, 0xd6}, 0x1e},
                {{0x9b, 0xdd}, 0x1c},

                {{0x9b, 0x84}, 0x13},
                {{0x99, 0x81}, 0x7f},
                {{0x99, 0x31}, 0x70},

                {{0x98, 0x00}, 0x3f},

                {{0x9f, 0x09}, 0x00},

                {{0x9f, 0x0a}, 0x05},

                {{0x9e, 0xd1}, 0xa1},
                {{0x99, 0x23}, 0x00},

                {{0x9e, 0x74}, 0x80},

                {{0x9f, 0x28}, 0x10},

                {{0x9f, 0x35}, 0x14},

                {{0x9f, 0x36}, 0x60},

                {{0x9c, 0x31}, 0x00},

                {{0x9c, 0x32}, 0xc8},

                {{0x9c, 0x19}, 0x40},

                {{0x9c, 0x1a}, 0x40},

                {{0x9c, 0x0c}, 0x00},

                {{0x9c, 0x0d}, 0x00},

                {{0x9c, 0x12}, 0x00},

                {{0x9c, 0x13}, 0x00},

                {{0x98, 0xa2}, 0x0e},

                {{0x98, 0x93}, 0x40},

                {{0x98, 0x7d}, 0x02},
                {{0x98, 0x7e}, 0x00},
                {{0x9f, 0xc8}, 0x01},
        };
        struct hw_config *p = hw_config;
        int count = ARRAY_SIZE(hw_config);
        struct sk_buff *res_skb;
        u8 param[4];
        int r;

        param[0] = 0;
        while (count--) {
                param[1] = p->adr[0];
                param[2] = p->adr[1];
                param[3] = p->value;

                r = nfc_hci_send_cmd(hdev, PN544_SYS_MGMT_GATE, PN544_WRITE,
                                     param, 4, &res_skb);
                if (r < 0)
                        return r;

                if (res_skb->len != 1) {
                        kfree_skb(res_skb);
                        return -EPROTO;
                }

                if (res_skb->data[0] != p->value) {
                        kfree_skb(res_skb);
                        return -EIO;
                }

                kfree_skb(res_skb);

                p++;
        }

        param[0] = NFC_HCI_UICC_HOST_ID;
        r = nfc_hci_set_param(hdev, NFC_HCI_ADMIN_GATE,
                              NFC_HCI_ADMIN_WHITELIST, param, 1);
        if (r < 0)
                return r;

        param[0] = 0x3d;
        r = nfc_hci_set_param(hdev, PN544_SYS_MGMT_GATE,
                              PN544_SYS_MGMT_INFO_NOTIFICATION, param, 1);
        if (r < 0)
                return r;

        param[0] = 0x0;
        r = nfc_hci_set_param(hdev, NFC_HCI_RF_READER_A_GATE,
                              PN544_RF_READER_A_AUTO_ACTIVATION, param, 1);
        if (r < 0)
                return r;

        r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
                               NFC_HCI_EVT_END_OPERATION, NULL, 0);
        if (r < 0)
                return r;

        param[0] = 0x1;
        r = nfc_hci_set_param(hdev, PN544_POLLING_LOOP_MGMT_GATE,
                              PN544_PL_NFCT_DEACTIVATED, param, 1);
        if (r < 0)
                return r;

        param[0] = 0x0;
        r = nfc_hci_set_param(hdev, PN544_POLLING_LOOP_MGMT_GATE,
                              PN544_PL_RDPHASES, param, 1);
        if (r < 0)
                return r;

        r = nfc_hci_get_param(hdev, NFC_HCI_ID_MGMT_GATE,
                              PN544_ID_MGMT_FULL_VERSION_SW, &skb);
        if (r < 0)
                return r;

        if (skb->len != FULL_VERSION_LEN) {
                kfree_skb(skb);
                return -EINVAL;
        }

        print_hex_dump(KERN_DEBUG, "FULL VERSION SOFTWARE INFO: ",
                       DUMP_PREFIX_NONE, 16, 1,
                       skb->data, FULL_VERSION_LEN, false);

        kfree_skb(skb);

        return 0;
}

static int pn544_hci_xmit(struct nfc_shdlc *shdlc, struct sk_buff *skb)
{
        struct pn544_hci_info *info = nfc_shdlc_get_clientdata(shdlc);
        struct i2c_client *client = info->i2c_dev;

        if (info->hard_fault != 0)
                return info->hard_fault;

        return pn544_hci_i2c_write(client, skb->data, skb->len);
}

static int pn544_hci_start_poll(struct nfc_shdlc *shdlc, u32 protocols)
{
        struct nfc_hci_dev *hdev = nfc_shdlc_get_hci_dev(shdlc);
        u8 phases = 0;
        int r;
        u8 duration[2];
        u8 activated;

        pr_info(DRIVER_DESC ": %s protocols = %d\n", __func__, protocols);

        r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
                               NFC_HCI_EVT_END_OPERATION, NULL, 0);
        if (r < 0)
                return r;

        duration[0] = 0x18;
        duration[1] = 0x6a;
        r = nfc_hci_set_param(hdev, PN544_POLLING_LOOP_MGMT_GATE,
                              PN544_PL_EMULATION, duration, 2);
        if (r < 0)
                return r;

        activated = 0;
        r = nfc_hci_set_param(hdev, PN544_POLLING_LOOP_MGMT_GATE,
                              PN544_PL_NFCT_DEACTIVATED, &activated, 1);
        if (r < 0)
                return r;

        if (protocols & (NFC_PROTO_ISO14443_MASK | NFC_PROTO_MIFARE_MASK |
                         NFC_PROTO_JEWEL_MASK))
                phases |= 1;            /* Type A */
        if (protocols & NFC_PROTO_FELICA_MASK) {
                phases |= (1 << 2);     /* Type F 212 */
                phases |= (1 << 3);     /* Type F 424 */
        }

        phases |= (1 << 5);             /* NFC active */

        r = nfc_hci_set_param(hdev, PN544_POLLING_LOOP_MGMT_GATE,
                              PN544_PL_RDPHASES, &phases, 1);
        if (r < 0)
                return r;

        r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
                               NFC_HCI_EVT_READER_REQUESTED, NULL, 0);
        if (r < 0)
                nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
                                   NFC_HCI_EVT_END_OPERATION, NULL, 0);

        return r;
}

static int pn544_hci_target_from_gate(struct nfc_shdlc *shdlc, u8 gate,
                                      struct nfc_target *target)
{
        switch (gate) {
        case PN544_RF_READER_F_GATE:
                target->supported_protocols = NFC_PROTO_FELICA_MASK;
                break;
        case PN544_RF_READER_JEWEL_GATE:
                target->supported_protocols = NFC_PROTO_JEWEL_MASK;
                target->sens_res = 0x0c00;
                break;
        default:
                return -EPROTO;
        }

        return 0;
}

static int pn544_hci_complete_target_discovered(struct nfc_shdlc *shdlc,
                                                u8 gate,
                                                struct nfc_target *target)
{
        struct nfc_hci_dev *hdev = nfc_shdlc_get_hci_dev(shdlc);
        struct sk_buff *uid_skb;
        int r = 0;

        if (target->supported_protocols & NFC_PROTO_MIFARE_MASK) {
                if (target->nfcid1_len != 4 && target->nfcid1_len != 7 &&
                    target->nfcid1_len != 10)
                        return -EPROTO;

                r = nfc_hci_send_cmd(hdev, NFC_HCI_RF_READER_A_GATE,
                                     PN544_RF_READER_CMD_ACTIVATE_NEXT,
                                     target->nfcid1, target->nfcid1_len, NULL);
        } else if (target->supported_protocols & NFC_PROTO_FELICA_MASK) {
                r = nfc_hci_get_param(hdev, PN544_RF_READER_F_GATE,
                                      PN544_FELICA_ID, &uid_skb);
                if (r < 0)
                        return r;

                if (uid_skb->len != 8) {
                        kfree_skb(uid_skb);
                        return -EPROTO;
                }

                r = nfc_hci_send_cmd(hdev, PN544_RF_READER_F_GATE,
                                     PN544_RF_READER_CMD_ACTIVATE_NEXT,
                                     uid_skb->data, uid_skb->len, NULL);
                kfree_skb(uid_skb);
        } else if (target->supported_protocols & NFC_PROTO_ISO14443_MASK) {
                /*
                 * TODO: maybe other ISO 14443 require some kind of continue
                 * activation, but for now we've seen only this one below.
                 */
                if (target->sens_res == 0x4403) /* Type 4 Mifare DESFire */
                        r = nfc_hci_send_cmd(hdev, NFC_HCI_RF_READER_A_GATE,
                              PN544_RF_READER_A_CMD_CONTINUE_ACTIVATION,
                              NULL, 0, NULL);
        }

        return r;
}

#define MIFARE_CMD_AUTH_KEY_A   0x60
#define MIFARE_CMD_AUTH_KEY_B   0x61
#define MIFARE_CMD_HEADER       2
#define MIFARE_UID_LEN          4
#define MIFARE_KEY_LEN          6
#define MIFARE_CMD_LEN          12
/*
 * Returns:
 * <= 0: driver handled the data exchange
 *    1: driver doesn't especially handle, please do standard processing
 */
static int pn544_hci_data_exchange(struct nfc_shdlc *shdlc,
                                   struct nfc_target *target,
                                   struct sk_buff *skb,
                                   struct sk_buff **res_skb)
{
        struct nfc_hci_dev *hdev = nfc_shdlc_get_hci_dev(shdlc);
        int r;

        pr_info(DRIVER_DESC ": %s for gate=%d\n", __func__,
                target->hci_reader_gate);

        switch (target->hci_reader_gate) {
        case NFC_HCI_RF_READER_A_GATE:
                if (target->supported_protocols & NFC_PROTO_MIFARE_MASK) {
                        /*
                         * It seems that pn544 is inverting key and UID for
                         * MIFARE authentication commands.
                         */
                        if (skb->len == MIFARE_CMD_LEN &&
                            (skb->data[0] == MIFARE_CMD_AUTH_KEY_A ||
                             skb->data[0] == MIFARE_CMD_AUTH_KEY_B)) {
                                u8 uid[MIFARE_UID_LEN];
                                u8 *data = skb->data + MIFARE_CMD_HEADER;

                                memcpy(uid, data + MIFARE_KEY_LEN,
                                       MIFARE_UID_LEN);
                                memmove(data + MIFARE_UID_LEN, data,
                                        MIFARE_KEY_LEN);
                                memcpy(data, uid, MIFARE_UID_LEN);
                        }

                        return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                                PN544_MIFARE_CMD,
                                                skb->data, skb->len, res_skb);
                } else
                        return 1;
        case PN544_RF_READER_F_GATE:
                *skb_push(skb, 1) = 0;
                *skb_push(skb, 1) = 0;

                r = nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                     PN544_FELICA_RAW,
                                     skb->data, skb->len, res_skb);
                if (r == 0)
                        skb_pull(*res_skb, 1);
                return r;
        case PN544_RF_READER_JEWEL_GATE:
                return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                        PN544_JEWEL_RAW_CMD,
                                        skb->data, skb->len, res_skb);
        default:
                return 1;
        }
}

static int pn544_hci_check_presence(struct nfc_shdlc *shdlc,
                                   struct nfc_target *target)
{
        struct nfc_hci_dev *hdev = nfc_shdlc_get_hci_dev(shdlc);

        return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                PN544_RF_READER_CMD_PRESENCE_CHECK,
                                NULL, 0, NULL);
}

static struct nfc_shdlc_ops pn544_shdlc_ops = {
        .open = pn544_hci_open,
        .close = pn544_hci_close,
        .hci_ready = pn544_hci_ready,
        .xmit = pn544_hci_xmit,
        .start_poll = pn544_hci_start_poll,
        .target_from_gate = pn544_hci_target_from_gate,
        .complete_target_discovered = pn544_hci_complete_target_discovered,
        .data_exchange = pn544_hci_data_exchange,
        .check_presence = pn544_hci_check_presence,
};

static int __devinit pn544_hci_probe(struct i2c_client *client,
                                     const struct i2c_device_id *id)
{
        struct pn544_hci_info *info;
        struct pn544_nfc_platform_data *pdata;
        int r = 0;
        u32 protocols;
        struct nfc_hci_init_data init_data;

        dev_dbg(&client->dev, "%s\n", __func__);
        dev_dbg(&client->dev, "IRQ: %d\n", client->irq);

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
                dev_err(&client->dev, "Need I2C_FUNC_I2C\n");
                return -ENODEV;
        }

        info = kzalloc(sizeof(struct pn544_hci_info), GFP_KERNEL);
        if (!info) {
                dev_err(&client->dev,
                        "Cannot allocate memory for pn544_hci_info.\n");
                r = -ENOMEM;
                goto err_info_alloc;
        }

        info->i2c_dev = client;
        info->state = PN544_ST_COLD;
        mutex_init(&info->info_lock);
        i2c_set_clientdata(client, info);

        pdata = client->dev.platform_data;
        if (pdata == NULL) {
                dev_err(&client->dev, "No platform data\n");
                r = -EINVAL;
                goto err_pdata;
        }

        if (pdata->request_resources == NULL) {
                dev_err(&client->dev, "request_resources() missing\n");
                r = -EINVAL;
                goto err_pdata;
        }

        r = pdata->request_resources(client);
        if (r) {
                dev_err(&client->dev, "Cannot get platform resources\n");
                goto err_pdata;
        }

        info->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE);
        info->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET);
        info->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ);

        pn544_hci_platform_init(info);

        r = request_threaded_irq(client->irq, NULL, pn544_hci_irq_thread_fn,
                                 IRQF_TRIGGER_RISING, PN544_HCI_DRIVER_NAME,
                                 info);
        if (r < 0) {
                dev_err(&client->dev, "Unable to register IRQ handler\n");
                goto err_rti;
        }

        init_data.gate_count = ARRAY_SIZE(pn544_custom_gates);

        memcpy(init_data.gates, pn544_custom_gates,
               ARRAY_SIZE(pn544_custom_gates));

        /*
         * TODO: Session id must include the driver name + some bus addr
         * persistent info to discriminate 2 identical chips
         */
        strcpy(init_data.session_id, "ID544HCI");

        protocols = NFC_PROTO_JEWEL_MASK |
                    NFC_PROTO_MIFARE_MASK |
                    NFC_PROTO_FELICA_MASK |
                    NFC_PROTO_ISO14443_MASK |
                    NFC_PROTO_NFC_DEP_MASK;

        info->shdlc = nfc_shdlc_allocate(&pn544_shdlc_ops,
                                         &init_data, protocols,
                                         PN544_CMDS_HEADROOM, 0,
                                         PN544_HCI_LLC_MAX_PAYLOAD,
                                         dev_name(&client->dev));
        if (!info->shdlc) {
                dev_err(&client->dev, "Cannot allocate nfc shdlc.\n");
                r = -ENOMEM;
                goto err_allocshdlc;
        }

        nfc_shdlc_set_clientdata(info->shdlc, info);

        return 0;

err_allocshdlc:
        free_irq(client->irq, info);

err_rti:
        if (pdata->free_resources != NULL)
                pdata->free_resources();

err_pdata:
        kfree(info);

err_info_alloc:
        return r;
}

static __devexit int pn544_hci_remove(struct i2c_client *client)
{
        struct pn544_hci_info *info = i2c_get_clientdata(client);
        struct pn544_nfc_platform_data *pdata = client->dev.platform_data;

        dev_dbg(&client->dev, "%s\n", __func__);

        nfc_shdlc_free(info->shdlc);

        if (info->state != PN544_ST_COLD) {
                if (pdata->disable)
                        pdata->disable();
        }

        free_irq(client->irq, info);
        if (pdata->free_resources)
                pdata->free_resources();

        kfree(info);

        return 0;
}

static struct i2c_driver pn544_hci_driver = {
        .driver = {
                   .name = PN544_HCI_DRIVER_NAME,
                  },
        .probe = pn544_hci_probe,
        .id_table = pn544_hci_id_table,
        .remove = __devexit_p(pn544_hci_remove),
};

static int __init pn544_hci_init(void)
{
        int r;

        pr_debug(DRIVER_DESC ": %s\n", __func__);

        r = i2c_add_driver(&pn544_hci_driver);
        if (r) {
                pr_err(PN544_HCI_DRIVER_NAME ": driver registration failed\n");
                return r;
        }

        return 0;
}

static void __exit pn544_hci_exit(void)
{
        i2c_del_driver(&pn544_hci_driver);
}

module_init(pn544_hci_init);
module_exit(pn544_hci_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION(DRIVER_DESC);