root/drivers/nfc/nfcmrvl/main.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Marvell NFC driver: major functions
 *
 * Copyright (C) 2014-2015 Marvell International Ltd.
 */

#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/of_gpio.h>
#include <linux/nfc.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include "nfcmrvl.h"

static int nfcmrvl_nci_open(struct nci_dev *ndev)
{
        struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
        int err;

        if (test_and_set_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
                return 0;

        /* Reset possible fault of previous session */
        clear_bit(NFCMRVL_PHY_ERROR, &priv->flags);

        err = priv->if_ops->nci_open(priv);

        if (err)
                clear_bit(NFCMRVL_NCI_RUNNING, &priv->flags);

        return err;
}

static int nfcmrvl_nci_close(struct nci_dev *ndev)
{
        struct nfcmrvl_private *priv = nci_get_drvdata(ndev);

        if (!test_and_clear_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
                return 0;

        priv->if_ops->nci_close(priv);

        return 0;
}

static int nfcmrvl_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
{
        struct nfcmrvl_private *priv = nci_get_drvdata(ndev);

        nfc_info(priv->dev, "send entry, len %d\n", skb->len);

        skb->dev = (void *)ndev;

        if (priv->config.hci_muxed) {
                unsigned char *hdr;
                unsigned char len = skb->len;

                hdr = skb_push(skb, NFCMRVL_HCI_EVENT_HEADER_SIZE);
                hdr[0] = NFCMRVL_HCI_COMMAND_CODE;
                hdr[1] = NFCMRVL_HCI_OGF;
                hdr[2] = NFCMRVL_HCI_OCF;
                hdr[3] = len;
        }

        return priv->if_ops->nci_send(priv, skb);
}

static int nfcmrvl_nci_setup(struct nci_dev *ndev)
{
        __u8 val = 1;

        nci_set_config(ndev, NFCMRVL_PB_BAIL_OUT, 1, &val);
        return 0;
}

static int nfcmrvl_nci_fw_download(struct nci_dev *ndev,
                                   const char *firmware_name)
{
        return nfcmrvl_fw_dnld_start(ndev, firmware_name);
}

static const struct nci_ops nfcmrvl_nci_ops = {
        .open = nfcmrvl_nci_open,
        .close = nfcmrvl_nci_close,
        .send = nfcmrvl_nci_send,
        .setup = nfcmrvl_nci_setup,
        .fw_download = nfcmrvl_nci_fw_download,
};

struct nfcmrvl_private *nfcmrvl_nci_register_dev(enum nfcmrvl_phy phy,
                                void *drv_data,
                                const struct nfcmrvl_if_ops *ops,
                                struct device *dev,
                                const struct nfcmrvl_platform_data *pdata)
{
        struct nfcmrvl_private *priv;
        int rc;
        int headroom;
        int tailroom;
        u32 protocols;

        priv = kzalloc_obj(*priv);
        if (!priv)
                return ERR_PTR(-ENOMEM);

        priv->drv_data = drv_data;
        priv->if_ops = ops;
        priv->dev = dev;
        priv->phy = phy;

        memcpy(&priv->config, pdata, sizeof(*pdata));

        if (gpio_is_valid(priv->config.reset_n_io)) {
                rc = gpio_request_one(priv->config.reset_n_io,
                                      GPIOF_OUT_INIT_LOW,
                                      "nfcmrvl_reset_n");
                if (rc < 0) {
                        priv->config.reset_n_io = -EINVAL;
                        nfc_err(dev, "failed to request reset_n io\n");
                }
        }

        if (phy == NFCMRVL_PHY_SPI) {
                headroom = NCI_SPI_HDR_LEN;
                tailroom = 1;
        } else
                headroom = tailroom = 0;

        if (priv->config.hci_muxed)
                headroom += NFCMRVL_HCI_EVENT_HEADER_SIZE;

        protocols = NFC_PROTO_JEWEL_MASK
                | NFC_PROTO_MIFARE_MASK
                | NFC_PROTO_FELICA_MASK
                | NFC_PROTO_ISO14443_MASK
                | NFC_PROTO_ISO14443_B_MASK
                | NFC_PROTO_ISO15693_MASK
                | NFC_PROTO_NFC_DEP_MASK;

        priv->ndev = nci_allocate_device(&nfcmrvl_nci_ops, protocols,
                                         headroom, tailroom);
        if (!priv->ndev) {
                nfc_err(dev, "nci_allocate_device failed\n");
                rc = -ENOMEM;
                goto error_free_gpio;
        }

        rc = nfcmrvl_fw_dnld_init(priv);
        if (rc) {
                nfc_err(dev, "failed to initialize FW download %d\n", rc);
                goto error_free_dev;
        }

        nci_set_drvdata(priv->ndev, priv);

        rc = nci_register_device(priv->ndev);
        if (rc) {
                nfc_err(dev, "nci_register_device failed %d\n", rc);
                goto error_fw_dnld_deinit;
        }

        /* Ensure that controller is powered off */
        nfcmrvl_chip_halt(priv);

        nfc_info(dev, "registered with nci successfully\n");
        return priv;

error_fw_dnld_deinit:
        nfcmrvl_fw_dnld_deinit(priv);
error_free_dev:
        nci_free_device(priv->ndev);
error_free_gpio:
        if (gpio_is_valid(priv->config.reset_n_io))
                gpio_free(priv->config.reset_n_io);
        kfree(priv);
        return ERR_PTR(rc);
}
EXPORT_SYMBOL_GPL(nfcmrvl_nci_register_dev);

void nfcmrvl_nci_unregister_dev(struct nfcmrvl_private *priv)
{
        struct nci_dev *ndev = priv->ndev;

        nci_unregister_device(ndev);
        if (priv->ndev->nfc_dev->fw_download_in_progress)
                nfcmrvl_fw_dnld_abort(priv);

        nfcmrvl_fw_dnld_deinit(priv);

        if (gpio_is_valid(priv->config.reset_n_io))
                gpio_free(priv->config.reset_n_io);

        nci_free_device(ndev);
        kfree(priv);
}
EXPORT_SYMBOL_GPL(nfcmrvl_nci_unregister_dev);

int nfcmrvl_nci_recv_frame(struct nfcmrvl_private *priv, struct sk_buff *skb)
{
        if (priv->config.hci_muxed) {
                if (skb->data[0] == NFCMRVL_HCI_EVENT_CODE &&
                    skb->data[1] == NFCMRVL_HCI_NFC_EVENT_CODE) {
                        /* Data packet, let's extract NCI payload */
                        skb_pull(skb, NFCMRVL_HCI_EVENT_HEADER_SIZE);
                } else {
                        /* Skip this packet */
                        kfree_skb(skb);
                        return 0;
                }
        }

        if (priv->ndev->nfc_dev->fw_download_in_progress) {
                nfcmrvl_fw_dnld_recv_frame(priv, skb);
                return 0;
        }

        if (test_bit(NFCMRVL_NCI_RUNNING, &priv->flags))
                nci_recv_frame(priv->ndev, skb);
        else {
                /* Drop this packet since nobody wants it */
                kfree_skb(skb);
                return 0;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(nfcmrvl_nci_recv_frame);

void nfcmrvl_chip_reset(struct nfcmrvl_private *priv)
{
        /* Reset possible fault of previous session */
        clear_bit(NFCMRVL_PHY_ERROR, &priv->flags);

        if (gpio_is_valid(priv->config.reset_n_io)) {
                nfc_info(priv->dev, "reset the chip\n");
                gpio_set_value(priv->config.reset_n_io, 0);
                usleep_range(5000, 10000);
                gpio_set_value(priv->config.reset_n_io, 1);
        } else
                nfc_info(priv->dev, "no reset available on this interface\n");
}

void nfcmrvl_chip_halt(struct nfcmrvl_private *priv)
{
        if (gpio_is_valid(priv->config.reset_n_io))
                gpio_set_value(priv->config.reset_n_io, 0);
}

int nfcmrvl_parse_dt(struct device_node *node,
                     struct nfcmrvl_platform_data *pdata)
{
        int reset_n_io;

        reset_n_io = of_get_named_gpio(node, "reset-n-io", 0);
        if (reset_n_io < 0) {
                pr_info("no reset-n-io config\n");
        } else if (!gpio_is_valid(reset_n_io)) {
                pr_err("invalid reset-n-io GPIO\n");
                return reset_n_io;
        }
        pdata->reset_n_io = reset_n_io;
        pdata->hci_muxed = of_property_read_bool(node, "hci-muxed");

        return 0;
}
EXPORT_SYMBOL_GPL(nfcmrvl_parse_dt);

MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell NFC driver");
MODULE_LICENSE("GPL v2");