// SPDX-License-Identifier: GPL-2.0
/*
 * Navman Serial USB driver
 *
 * Copyright (C) 2006 Greg Kroah-Hartman <gregkh@suse.de>
 *
 * TODO:
 *      Add termios method that uses copy_hw but also kills all echo
 *      flags as the navman is rx only so cannot echo.
 */

#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>

static const struct usb_device_id id_table[] = {
        { USB_DEVICE(0x0a99, 0x0001) }, /* Talon Technology device */
        { USB_DEVICE(0x0df7, 0x0900) }, /* Mobile Action i-gotU */
        { },
};
MODULE_DEVICE_TABLE(usb, id_table);

static void navman_read_int_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        unsigned char *data = urb->transfer_buffer;
        int status = urb->status;
        int result;

        switch (status) {
        case 0:
                /* success */
                break;
        case -ECONNRESET:
        case -ENOENT:
        case -ESHUTDOWN:
                /* this urb is terminated, clean up */
                dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
                        __func__, status);
                return;
        default:
                dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
                        __func__, status);
                goto exit;
        }

        usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);

        if (urb->actual_length) {
                tty_insert_flip_string(&port->port, data, urb->actual_length);
                tty_flip_buffer_push(&port->port);
        }

exit:
        result = usb_submit_urb(urb, GFP_ATOMIC);
        if (result)
                dev_err(&urb->dev->dev,
                        "%s - Error %d submitting interrupt urb\n",
                        __func__, result);
}

static int navman_open(struct tty_struct *tty, struct usb_serial_port *port)
{
        int result = 0;

        if (port->interrupt_in_urb) {
                dev_dbg(&port->dev, "%s - adding interrupt input for treo\n",
                        __func__);
                result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
                if (result)
                        dev_err(&port->dev,
                                "%s - failed submitting interrupt urb, error %d\n",
                                __func__, result);
        }
        return result;
}

static void navman_close(struct usb_serial_port *port)
{
        usb_kill_urb(port->interrupt_in_urb);
}

static int navman_write(struct tty_struct *tty, struct usb_serial_port *port,
                        const unsigned char *buf, int count)
{
        /*
         * This device can't write any data, only read from the device
         */
        return -EOPNOTSUPP;
}

static struct usb_serial_driver navman_device = {
        .driver = {
                .name =         "navman",
        },
        .id_table =             id_table,
        .num_ports =            1,
        .open =                 navman_open,
        .close =                navman_close,
        .write =                navman_write,
        .read_int_callback =    navman_read_int_callback,
};

static struct usb_serial_driver * const serial_drivers[] = {
        &navman_device, NULL
};

module_usb_serial_driver(serial_drivers, id_table);

MODULE_DESCRIPTION("Navman USB Serial driver");
MODULE_LICENSE("GPL v2");