root/drivers/nfc/nxp-nci/core.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Generic driver for NXP NCI NFC chips
 *
 * Copyright (C) 2014  NXP Semiconductors  All rights reserved.
 *
 * Authors: Clément Perrochaud <clement.perrochaud@nxp.com>
 *
 * Derived from PN544 device driver:
 * Copyright (C) 2012  Intel Corporation. All rights reserved.
 */

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

#include <net/nfc/nci_core.h>

#include "nxp-nci.h"

#define NXP_NCI_HDR_LEN 4

#define NXP_NCI_NFC_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)

#define NXP_NCI_RF_PLL_UNLOCKED_NTF nci_opcode_pack(NCI_GID_RF_MGMT, 0x21)
#define NXP_NCI_RF_TXLDO_ERROR_NTF nci_opcode_pack(NCI_GID_RF_MGMT, 0x23)

static int nxp_nci_open(struct nci_dev *ndev)
{
        struct nxp_nci_info *info = nci_get_drvdata(ndev);
        int r = 0;

        mutex_lock(&info->info_lock);

        if (info->mode != NXP_NCI_MODE_COLD) {
                r = -EBUSY;
                goto open_exit;
        }

        if (info->phy_ops->set_mode)
                r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_NCI);

        info->mode = NXP_NCI_MODE_NCI;

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

static int nxp_nci_close(struct nci_dev *ndev)
{
        struct nxp_nci_info *info = nci_get_drvdata(ndev);
        int r = 0;

        mutex_lock(&info->info_lock);

        if (info->phy_ops->set_mode)
                r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);

        info->mode = NXP_NCI_MODE_COLD;

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

static int nxp_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
{
        struct nxp_nci_info *info = nci_get_drvdata(ndev);
        int r;

        if (!info->phy_ops->write) {
                kfree_skb(skb);
                return -EOPNOTSUPP;
        }

        if (info->mode != NXP_NCI_MODE_NCI) {
                kfree_skb(skb);
                return -EINVAL;
        }

        r = info->phy_ops->write(info->phy_id, skb);
        if (r < 0) {
                kfree_skb(skb);
                return r;
        }

        consume_skb(skb);
        return 0;
}

static int nxp_nci_rf_pll_unlocked_ntf(struct nci_dev *ndev,
                                       struct sk_buff *skb)
{
        nfc_err(&ndev->nfc_dev->dev,
                "PLL didn't lock. Missing or unstable clock?\n");

        return 0;
}

static int nxp_nci_rf_txldo_error_ntf(struct nci_dev *ndev,
                                      struct sk_buff *skb)
{
        nfc_err(&ndev->nfc_dev->dev,
                "RF transmitter couldn't start. Bad power and/or configuration?\n");

        return 0;
}

static const struct nci_driver_ops nxp_nci_core_ops[] = {
        {
                .opcode = NXP_NCI_RF_PLL_UNLOCKED_NTF,
                .ntf = nxp_nci_rf_pll_unlocked_ntf,
        },
        {
                .opcode = NXP_NCI_RF_TXLDO_ERROR_NTF,
                .ntf = nxp_nci_rf_txldo_error_ntf,
        },
};

static const struct nci_ops nxp_nci_ops = {
        .open = nxp_nci_open,
        .close = nxp_nci_close,
        .send = nxp_nci_send,
        .fw_download = nxp_nci_fw_download,
        .core_ops = nxp_nci_core_ops,
        .n_core_ops = ARRAY_SIZE(nxp_nci_core_ops),
};

int nxp_nci_probe(void *phy_id, struct device *pdev,
                  const struct nxp_nci_phy_ops *phy_ops,
                  unsigned int max_payload,
                  struct nci_dev **ndev)
{
        struct nxp_nci_info *info;
        int r;

        info = devm_kzalloc(pdev, sizeof(struct nxp_nci_info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        info->phy_id = phy_id;
        info->pdev = pdev;
        info->phy_ops = phy_ops;
        info->max_payload = max_payload;
        INIT_WORK(&info->fw_info.work, nxp_nci_fw_work);
        init_completion(&info->fw_info.cmd_completion);
        mutex_init(&info->info_lock);

        if (info->phy_ops->set_mode) {
                r = info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);
                if (r < 0)
                        return r;
        }

        info->mode = NXP_NCI_MODE_COLD;

        info->ndev = nci_allocate_device(&nxp_nci_ops, NXP_NCI_NFC_PROTOCOLS,
                                         NXP_NCI_HDR_LEN, 0);
        if (!info->ndev)
                return -ENOMEM;

        nci_set_parent_dev(info->ndev, pdev);
        nci_set_drvdata(info->ndev, info);
        r = nci_register_device(info->ndev);
        if (r < 0) {
                nci_free_device(info->ndev);
                return r;
        }

        *ndev = info->ndev;
        return r;
}
EXPORT_SYMBOL(nxp_nci_probe);

void nxp_nci_remove(struct nci_dev *ndev)
{
        struct nxp_nci_info *info = nci_get_drvdata(ndev);

        if (info->mode == NXP_NCI_MODE_FW)
                nxp_nci_fw_work_complete(info, -ESHUTDOWN);
        cancel_work_sync(&info->fw_info.work);

        mutex_lock(&info->info_lock);

        if (info->phy_ops->set_mode)
                info->phy_ops->set_mode(info->phy_id, NXP_NCI_MODE_COLD);

        nci_unregister_device(ndev);
        nci_free_device(ndev);

        mutex_unlock(&info->info_lock);
}
EXPORT_SYMBOL(nxp_nci_remove);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("NXP NCI NFC driver");
MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>");