// SPDX-License-Identifier: GPL-2.0-only
/*
 * HCI based Driver for NXP PN544 NFC Chip
 *
 * Copyright (C) 2012  Intel Corporation. All rights reserved.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/module.h>

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

#include "pn544.h"

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

enum pn544_state {
        PN544_ST_COLD,
        PN544_ST_FW_READY,
        PN544_ST_READY,
};

#define FULL_VERSION_LEN 11

/* Proprietary commands */
#define PN544_WRITE             0x3f
#define PN544_TEST_SWP          0x21

/* 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_DEP_MODE                          0x01
#define PN544_DEP_ATR_REQ                       0x02
#define PN544_DEP_ATR_RES                       0x03
#define PN544_DEP_MERGE                         0x0D
#define PN544_PL_RDPHASES                       0x06
#define PN544_PL_EMULATION                      0x07
#define PN544_PL_NFCT_DEACTIVATED               0x09

#define PN544_SWP_MGMT_GATE                     0xA0
#define PN544_SWP_DEFAULT_MODE                  0x01

#define PN544_NFC_WI_MGMT_GATE                  0xA1
#define PN544_NFC_ESE_DEFAULT_MODE              0x01

#define PN544_HCI_EVT_SND_DATA                  0x01
#define PN544_HCI_EVT_ACTIVATED                 0x02
#define PN544_HCI_EVT_DEACTIVATED               0x03
#define PN544_HCI_EVT_RCV_DATA                  0x04
#define PN544_HCI_EVT_CONTINUE_MI               0x05
#define PN544_HCI_EVT_SWITCH_MODE               0x03

#define PN544_HCI_CMD_ATTREQUEST                0x12
#define PN544_HCI_CMD_CONTINUE_ACTIVATION       0x13

static const struct nfc_hci_gate pn544_gates[] = {
        {NFC_HCI_ADMIN_GATE, NFC_HCI_INVALID_PIPE},
        {NFC_HCI_LOOPBACK_GATE, NFC_HCI_INVALID_PIPE},
        {NFC_HCI_ID_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {NFC_HCI_LINK_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {NFC_HCI_RF_READER_B_GATE, NFC_HCI_INVALID_PIPE},
        {NFC_HCI_RF_READER_A_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_SYS_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_SWP_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_POLLING_LOOP_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_NFC_WI_MGMT_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_RF_READER_F_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_RF_READER_JEWEL_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_RF_READER_ISO15693_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_RF_READER_NFCIP1_INITIATOR_GATE, NFC_HCI_INVALID_PIPE},
        {PN544_RF_READER_NFCIP1_TARGET_GATE, NFC_HCI_INVALID_PIPE}
};

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

struct pn544_hci_info {
        const struct nfc_phy_ops *phy_ops;
        void *phy_id;

        struct nfc_hci_dev *hdev;

        enum pn544_state state;

        struct mutex info_lock;

        int async_cb_type;
        data_exchange_cb_t async_cb;
        void *async_cb_context;

        fw_download_t fw_download;
};

static int pn544_hci_open(struct nfc_hci_dev *hdev)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);
        int r = 0;

        mutex_lock(&info->info_lock);

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

        r = info->phy_ops->enable(info->phy_id);

        if (r == 0)
                info->state = PN544_ST_READY;

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

static void pn544_hci_close(struct nfc_hci_dev *hdev)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

        mutex_lock(&info->info_lock);

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

        info->phy_ops->disable(info->phy_id);

        info->state = PN544_ST_COLD;

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

static int pn544_hci_ready(struct nfc_hci_dev *hdev)
{
        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},

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

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

                {{0x9b, 0xd1}, 0x17},
                {{0x9b, 0xd2}, 0x58},
                {{0x9b, 0xd3}, 0x10},
                {{0x9b, 0xd4}, 0x47},
                {{0x9b, 0xd5}, 0x0c},
                {{0x9b, 0xd6}, 0x37},
                {{0x9b, 0xdd}, 0x33},

                {{0x9b, 0x84}, 0x00},
                {{0x99, 0x81}, 0x79},
                {{0x99, 0x31}, 0x79},

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

                {{0x9f, 0x09}, 0x02},

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

                {{0x9e, 0xd1}, 0xa1},
                {{0x99, 0x23}, 0x01},

                {{0x9e, 0x74}, 0x00},
                {{0x9e, 0x90}, 0x00},
                {{0x9f, 0x28}, 0x10},

                {{0x9f, 0x35}, 0x04},

                {{0x9f, 0x36}, 0x11},

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

                {{0x9c, 0x32}, 0x00},

                {{0x9c, 0x19}, 0x0a},

                {{0x9c, 0x1a}, 0x0a},

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

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

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

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

                {{0x98, 0xa2}, 0x09},

                {{0x98, 0x93}, 0x00},

                {{0x98, 0x7d}, 0x08},
                {{0x98, 0x7e}, 0x00},
                {{0x9f, 0xc8}, 0x00},
        };
        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_hci_dev *hdev, struct sk_buff *skb)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

        return info->phy_ops->write(info->phy_id, skb);
}

static int pn544_hci_start_poll(struct nfc_hci_dev *hdev,
                                u32 im_protocols, u32 tm_protocols)
{
        u8 phases = 0;
        int r;
        u8 duration[2];
        u8 activated;
        u8 i_mode = 0x3f; /* Enable all supported modes */
        u8 t_mode = 0x0f;
        u8 t_merge = 0x01; /* Enable merge by default */

        pr_info(DRIVER_DESC ": %s protocols 0x%x 0x%x\n",
                __func__, im_protocols, tm_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 (im_protocols & (NFC_PROTO_ISO14443_MASK | NFC_PROTO_MIFARE_MASK |
                         NFC_PROTO_JEWEL_MASK))
                phases |= 1;            /* Type A */
        if (im_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;

        if ((im_protocols | tm_protocols) & NFC_PROTO_NFC_DEP_MASK) {
                hdev->gb = nfc_get_local_general_bytes(hdev->ndev,
                                                        &hdev->gb_len);
                pr_debug("generate local bytes %p\n", hdev->gb);
                if (hdev->gb == NULL || hdev->gb_len == 0) {
                        im_protocols &= ~NFC_PROTO_NFC_DEP_MASK;
                        tm_protocols &= ~NFC_PROTO_NFC_DEP_MASK;
                }
        }

        if (im_protocols & NFC_PROTO_NFC_DEP_MASK) {
                r = nfc_hci_send_event(hdev,
                                PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                NFC_HCI_EVT_END_OPERATION, NULL, 0);
                if (r < 0)
                        return r;

                r = nfc_hci_set_param(hdev,
                                PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                PN544_DEP_MODE, &i_mode, 1);
                if (r < 0)
                        return r;

                r = nfc_hci_set_param(hdev,
                                PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                PN544_DEP_ATR_REQ, hdev->gb, hdev->gb_len);
                if (r < 0)
                        return r;

                r = nfc_hci_send_event(hdev,
                                PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                NFC_HCI_EVT_READER_REQUESTED, NULL, 0);
                if (r < 0)
                        nfc_hci_send_event(hdev,
                                        PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                        NFC_HCI_EVT_END_OPERATION, NULL, 0);
        }

        if (tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
                r = nfc_hci_set_param(hdev, PN544_RF_READER_NFCIP1_TARGET_GATE,
                                PN544_DEP_MODE, &t_mode, 1);
                if (r < 0)
                        return r;

                r = nfc_hci_set_param(hdev, PN544_RF_READER_NFCIP1_TARGET_GATE,
                                PN544_DEP_ATR_RES, hdev->gb, hdev->gb_len);
                if (r < 0)
                        return r;

                r = nfc_hci_set_param(hdev, PN544_RF_READER_NFCIP1_TARGET_GATE,
                                PN544_DEP_MERGE, &t_merge, 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_dep_link_up(struct nfc_hci_dev *hdev,
                                struct nfc_target *target, u8 comm_mode,
                                u8 *gb, size_t gb_len)
{
        struct sk_buff *rgb_skb = NULL;
        int r;

        r = nfc_hci_get_param(hdev, target->hci_reader_gate,
                                PN544_DEP_ATR_RES, &rgb_skb);
        if (r < 0)
                return r;

        if (rgb_skb->len == 0 || rgb_skb->len > NFC_GB_MAXSIZE) {
                r = -EPROTO;
                goto exit;
        }
        print_hex_dump(KERN_DEBUG, "remote gb: ", DUMP_PREFIX_OFFSET,
                        16, 1, rgb_skb->data, rgb_skb->len, true);

        r = nfc_set_remote_general_bytes(hdev->ndev, rgb_skb->data,
                                                rgb_skb->len);

        if (r == 0)
                r = nfc_dep_link_is_up(hdev->ndev, target->idx, comm_mode,
                                        NFC_RF_INITIATOR);
exit:
        kfree_skb(rgb_skb);
        return r;
}

static int pn544_hci_dep_link_down(struct nfc_hci_dev *hdev)
{

        return nfc_hci_send_event(hdev, PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                        NFC_HCI_EVT_END_OPERATION, NULL, 0);
}

static int pn544_hci_target_from_gate(struct nfc_hci_dev *hdev, 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;
        case PN544_RF_READER_NFCIP1_INITIATOR_GATE:
                target->supported_protocols = NFC_PROTO_NFC_DEP_MASK;
                break;
        default:
                return -EPROTO;
        }

        return 0;
}

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

        if (gate == PN544_RF_READER_NFCIP1_INITIATOR_GATE)
                return r;

        if (target->supported_protocols & NFC_PROTO_NFC_DEP_MASK) {
                r = nfc_hci_send_cmd(hdev,
                        PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                        PN544_HCI_CMD_CONTINUE_ACTIVATION, NULL, 0, NULL);
                if (r < 0)
                        return r;

                target->hci_reader_gate = PN544_RF_READER_NFCIP1_INITIATOR_GATE;
        } else 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;
                }

                /* Type F NFC-DEP IDm has prefix 0x01FE */
                if ((uid_skb->data[0] == 0x01) && (uid_skb->data[1] == 0xfe)) {
                        kfree_skb(uid_skb);
                        r = nfc_hci_send_cmd(hdev,
                                        PN544_RF_READER_NFCIP1_INITIATOR_GATE,
                                        PN544_HCI_CMD_CONTINUE_ACTIVATION,
                                        NULL, 0, NULL);
                        if (r < 0)
                                return r;

                        target->supported_protocols = NFC_PROTO_NFC_DEP_MASK;
                        target->hci_reader_gate =
                                PN544_RF_READER_NFCIP1_INITIATOR_GATE;
                } else {
                        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 PN544_CB_TYPE_READER_F 1

static void pn544_hci_data_exchange_cb(void *context, struct sk_buff *skb,
                                       int err)
{
        struct pn544_hci_info *info = context;

        switch (info->async_cb_type) {
        case PN544_CB_TYPE_READER_F:
                if (err == 0)
                        skb_pull(skb, 1);
                info->async_cb(info->async_cb_context, skb, err);
                break;
        default:
                if (err == 0)
                        kfree_skb(skb);
                break;
        }
}

#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_im_transceive(struct nfc_hci_dev *hdev,
                                   struct nfc_target *target,
                                   struct sk_buff *skb, data_exchange_cb_t cb,
                                   void *cb_context)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

        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_async(hdev,
                                                      target->hci_reader_gate,
                                                      PN544_MIFARE_CMD,
                                                      skb->data, skb->len,
                                                      cb, cb_context);
                } else
                        return 1;
        case PN544_RF_READER_F_GATE:
                *(u8 *)skb_push(skb, 1) = 0;
                *(u8 *)skb_push(skb, 1) = 0;

                info->async_cb_type = PN544_CB_TYPE_READER_F;
                info->async_cb = cb;
                info->async_cb_context = cb_context;

                return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
                                              PN544_FELICA_RAW, skb->data,
                                              skb->len,
                                              pn544_hci_data_exchange_cb, info);
        case PN544_RF_READER_JEWEL_GATE:
                return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
                                              PN544_JEWEL_RAW_CMD, skb->data,
                                              skb->len, cb, cb_context);
        case PN544_RF_READER_NFCIP1_INITIATOR_GATE:
                *(u8 *)skb_push(skb, 1) = 0;

                return nfc_hci_send_event(hdev, target->hci_reader_gate,
                                        PN544_HCI_EVT_SND_DATA, skb->data,
                                        skb->len);
        default:
                return 1;
        }
}

static int pn544_hci_tm_send(struct nfc_hci_dev *hdev, struct sk_buff *skb)
{
        int r;

        /* Set default false for multiple information chaining */
        *(u8 *)skb_push(skb, 1) = 0;

        r = nfc_hci_send_event(hdev, PN544_RF_READER_NFCIP1_TARGET_GATE,
                               PN544_HCI_EVT_SND_DATA, skb->data, skb->len);

        kfree_skb(skb);

        return r;
}

static int pn544_hci_check_presence(struct nfc_hci_dev *hdev,
                                   struct nfc_target *target)
{
        pr_debug("supported protocol %d\n", target->supported_protocols);
        if (target->supported_protocols & (NFC_PROTO_ISO14443_MASK |
                                        NFC_PROTO_ISO14443_B_MASK)) {
                return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                        PN544_RF_READER_CMD_PRESENCE_CHECK,
                                        NULL, 0, NULL);
        } else if (target->supported_protocols & NFC_PROTO_MIFARE_MASK) {
                if (target->nfcid1_len != 4 && target->nfcid1_len != 7 &&
                    target->nfcid1_len != 10)
                        return -EOPNOTSUPP;

                return 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_JEWEL_MASK |
                                                NFC_PROTO_FELICA_MASK)) {
                return -EOPNOTSUPP;
        } else if (target->supported_protocols & NFC_PROTO_NFC_DEP_MASK) {
                return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
                                        PN544_HCI_CMD_ATTREQUEST,
                                        NULL, 0, NULL);
        }

        return 0;
}

/*
 * Returns:
 * <= 0: driver handled the event, skb consumed
 *    1: driver does not handle the event, please do standard processing
 */
static int pn544_hci_event_received(struct nfc_hci_dev *hdev, u8 pipe, u8 event,
                                    struct sk_buff *skb)
{
        struct sk_buff *rgb_skb = NULL;
        u8 gate = hdev->pipes[pipe].gate;
        int r;

        pr_debug("hci event %d\n", event);
        switch (event) {
        case PN544_HCI_EVT_ACTIVATED:
                if (gate == PN544_RF_READER_NFCIP1_INITIATOR_GATE) {
                        r = nfc_hci_target_discovered(hdev, gate);
                } else if (gate == PN544_RF_READER_NFCIP1_TARGET_GATE) {
                        r = nfc_hci_get_param(hdev, gate, PN544_DEP_ATR_REQ,
                                              &rgb_skb);
                        if (r < 0)
                                goto exit;

                        r = nfc_tm_activated(hdev->ndev, NFC_PROTO_NFC_DEP_MASK,
                                             NFC_COMM_PASSIVE, rgb_skb->data,
                                             rgb_skb->len);

                        kfree_skb(rgb_skb);
                } else {
                        r = -EINVAL;
                }
                break;
        case PN544_HCI_EVT_DEACTIVATED:
                r = nfc_hci_send_event(hdev, gate, NFC_HCI_EVT_END_OPERATION,
                                       NULL, 0);
                break;
        case PN544_HCI_EVT_RCV_DATA:
                if (skb->len < 2) {
                        r = -EPROTO;
                        goto exit;
                }

                if (skb->data[0] != 0) {
                        pr_debug("data0 %d\n", skb->data[0]);
                        r = -EPROTO;
                        goto exit;
                }

                skb_pull(skb, 2);
                return nfc_tm_data_received(hdev->ndev, skb);
        default:
                return 1;
        }

exit:
        kfree_skb(skb);

        return r;
}

static int pn544_hci_fw_download(struct nfc_hci_dev *hdev,
                                 const char *firmware_name)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

        if (info->fw_download == NULL)
                return -ENOTSUPP;

        return info->fw_download(info->phy_id, firmware_name, hdev->sw_romlib);
}

static int pn544_hci_discover_se(struct nfc_hci_dev *hdev)
{
        u32 se_idx = 0;
        u8 ese_mode = 0x01; /* Default mode */
        struct sk_buff *res_skb;
        int r;

        r = nfc_hci_send_cmd(hdev, PN544_SYS_MGMT_GATE, PN544_TEST_SWP,
                             NULL, 0, &res_skb);

        if (r == 0) {
                if (res_skb->len == 2 && res_skb->data[0] == 0x00)
                        nfc_add_se(hdev->ndev, se_idx++, NFC_SE_UICC);

                kfree_skb(res_skb);
        }

        r = nfc_hci_send_event(hdev, PN544_NFC_WI_MGMT_GATE,
                                PN544_HCI_EVT_SWITCH_MODE,
                                &ese_mode, 1);
        if (r == 0)
                nfc_add_se(hdev->ndev, se_idx++, NFC_SE_EMBEDDED);

        return !se_idx;
}

#define PN544_SE_MODE_OFF       0x00
#define PN544_SE_MODE_ON        0x01
static int pn544_hci_enable_se(struct nfc_hci_dev *hdev, u32 se_idx)
{
        const struct nfc_se *se;
        u8 enable = PN544_SE_MODE_ON;
        static struct uicc_gatelist {
                u8 head;
                u8 adr[2];
                u8 value;
        } uicc_gatelist[] = {
                {0x00, {0x9e, 0xd9}, 0x23},
                {0x00, {0x9e, 0xda}, 0x21},
                {0x00, {0x9e, 0xdb}, 0x22},
                {0x00, {0x9e, 0xdc}, 0x24},
        };
        struct uicc_gatelist *p = uicc_gatelist;
        int count = ARRAY_SIZE(uicc_gatelist);
        struct sk_buff *res_skb;
        int r;

        se = nfc_find_se(hdev->ndev, se_idx);

        switch (se->type) {
        case NFC_SE_UICC:
                while (count--) {
                        r = nfc_hci_send_cmd(hdev, PN544_SYS_MGMT_GATE,
                                        PN544_WRITE, (u8 *)p, 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++;
                }

                return nfc_hci_set_param(hdev, PN544_SWP_MGMT_GATE,
                              PN544_SWP_DEFAULT_MODE, &enable, 1);
        case NFC_SE_EMBEDDED:
                return nfc_hci_set_param(hdev, PN544_NFC_WI_MGMT_GATE,
                              PN544_NFC_ESE_DEFAULT_MODE, &enable, 1);

        default:
                return -EINVAL;
        }
}

static int pn544_hci_disable_se(struct nfc_hci_dev *hdev, u32 se_idx)
{
        const struct nfc_se *se;
        u8 disable = PN544_SE_MODE_OFF;

        se = nfc_find_se(hdev->ndev, se_idx);

        switch (se->type) {
        case NFC_SE_UICC:
                return nfc_hci_set_param(hdev, PN544_SWP_MGMT_GATE,
                              PN544_SWP_DEFAULT_MODE, &disable, 1);
        case NFC_SE_EMBEDDED:
                return nfc_hci_set_param(hdev, PN544_NFC_WI_MGMT_GATE,
                              PN544_NFC_ESE_DEFAULT_MODE, &disable, 1);
        default:
                return -EINVAL;
        }
}

static const struct nfc_hci_ops pn544_hci_ops = {
        .open = pn544_hci_open,
        .close = pn544_hci_close,
        .hci_ready = pn544_hci_ready,
        .xmit = pn544_hci_xmit,
        .start_poll = pn544_hci_start_poll,
        .dep_link_up = pn544_hci_dep_link_up,
        .dep_link_down = pn544_hci_dep_link_down,
        .target_from_gate = pn544_hci_target_from_gate,
        .complete_target_discovered = pn544_hci_complete_target_discovered,
        .im_transceive = pn544_hci_im_transceive,
        .tm_send = pn544_hci_tm_send,
        .check_presence = pn544_hci_check_presence,
        .event_received = pn544_hci_event_received,
        .fw_download = pn544_hci_fw_download,
        .discover_se = pn544_hci_discover_se,
        .enable_se = pn544_hci_enable_se,
        .disable_se = pn544_hci_disable_se,
};

int pn544_hci_probe(void *phy_id, const struct nfc_phy_ops *phy_ops,
                    char *llc_name, int phy_headroom, int phy_tailroom,
                    int phy_payload, fw_download_t fw_download,
                    struct nfc_hci_dev **hdev)
{
        struct pn544_hci_info *info;
        u32 protocols;
        struct nfc_hci_init_data init_data;
        int r;

        info = kzalloc_obj(struct pn544_hci_info);
        if (!info) {
                r = -ENOMEM;
                goto err_info_alloc;
        }

        info->phy_ops = phy_ops;
        info->phy_id = phy_id;
        info->fw_download = fw_download;
        info->state = PN544_ST_COLD;
        mutex_init(&info->info_lock);

        init_data.gate_count = ARRAY_SIZE(pn544_gates);

        memcpy(init_data.gates, pn544_gates, sizeof(pn544_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_ISO14443_B_MASK |
                    NFC_PROTO_NFC_DEP_MASK;

        info->hdev = nfc_hci_allocate_device(&pn544_hci_ops, &init_data, 0,
                                             protocols, llc_name,
                                             phy_headroom + PN544_CMDS_HEADROOM,
                                             phy_tailroom, phy_payload);
        if (!info->hdev) {
                pr_err("Cannot allocate nfc hdev\n");
                r = -ENOMEM;
                goto err_alloc_hdev;
        }

        nfc_hci_set_clientdata(info->hdev, info);

        r = nfc_hci_register_device(info->hdev);
        if (r)
                goto err_regdev;

        *hdev = info->hdev;

        return 0;

err_regdev:
        nfc_hci_free_device(info->hdev);

err_alloc_hdev:
        kfree(info);

err_info_alloc:
        return r;
}
EXPORT_SYMBOL(pn544_hci_probe);

void pn544_hci_remove(struct nfc_hci_dev *hdev)
{
        struct pn544_hci_info *info = nfc_hci_get_clientdata(hdev);

        nfc_hci_unregister_device(hdev);
        nfc_hci_free_device(hdev);
        kfree(info);
}
EXPORT_SYMBOL(pn544_hci_remove);

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