// SPDX-License-Identifier: GPL-2.0
/* dvb-usb-firmware.c is part of the DVB USB library.
 *
 * Copyright (C) 2004-6 Patrick Boettcher (patrick.boettcher@posteo.de)
 * see dvb-usb-init.c for copyright information.
 *
 * This file contains functions for downloading the firmware to Cypress FX 1 and 2 based devices.
 *
 * FIXME: This part does actually not belong to dvb-usb, but to the usb-subsystem.
 */
#include "dvb-usb-common.h"

#include <linux/usb.h>

struct usb_cypress_controller {
        int id;
        const char *name;       /* name of the usb controller */
        u16 cpu_cs_register;    /* needs to be restarted, when the firmware has been downloaded. */
};

static struct usb_cypress_controller cypress[] = {
        { .id = DEVICE_SPECIFIC, .name = "Device specific", .cpu_cs_register = 0 },
        { .id = CYPRESS_AN2135,  .name = "Cypress AN2135",  .cpu_cs_register = 0x7f92 },
        { .id = CYPRESS_AN2235,  .name = "Cypress AN2235",  .cpu_cs_register = 0x7f92 },
        { .id = CYPRESS_FX2,     .name = "Cypress FX2",     .cpu_cs_register = 0xe600 },
};

/*
 * load a firmware packet to the device
 */
static int usb_cypress_writemem(struct usb_device *udev,u16 addr,u8 *data, u8 len)
{
        return usb_control_msg(udev, usb_sndctrlpipe(udev,0),
                        0xa0, USB_TYPE_VENDOR, addr, 0x00, data, len, 5000);
}

int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware *fw, int type)
{
        struct hexline *hx;
        u8 *buf;
        int ret, pos = 0;
        u16 cpu_cs_register = cypress[type].cpu_cs_register;

        buf = kmalloc(sizeof(*hx), GFP_KERNEL);
        if (!buf)
                return -ENOMEM;
        hx = (struct hexline *)buf;

        /* stop the CPU */
        buf[0] = 1;
        if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1)
                err("could not stop the USB controller CPU.");

        while ((ret = dvb_usb_get_hexline(fw, hx, &pos)) > 0) {
                deb_fw("writing to address 0x%04x (buffer: 0x%02x %02x)\n", hx->addr, hx->len, hx->chk);
                ret = usb_cypress_writemem(udev, hx->addr, hx->data, hx->len);

                if (ret != hx->len) {
                        err("error while transferring firmware (transferred size: %d, block size: %d)",
                                ret, hx->len);
                        ret = -EINVAL;
                        break;
                }
        }
        if (ret < 0) {
                err("firmware download failed at %d with %d",pos,ret);
                kfree(buf);
                return ret;
        }

        if (ret == 0) {
                /* restart the CPU */
                buf[0] = 0;
                if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) {
                        err("could not restart the USB controller CPU.");
                        ret = -EINVAL;
                }
        } else
                ret = -EIO;

        kfree(buf);

        return ret;
}
EXPORT_SYMBOL(usb_cypress_load_firmware);

int dvb_usb_download_firmware(struct usb_device *udev,
                              const struct dvb_usb_device_properties *props)
{
        int ret;
        const struct firmware *fw = NULL;

        if ((ret = request_firmware(&fw, props->firmware, &udev->dev)) != 0) {
                err("did not find the firmware file '%s' (status %d). You can use <kernel_dir>/scripts/get_dvb_firmware to get the firmware",
                        props->firmware,ret);
                return ret;
        }

        info("downloading firmware from file '%s'",props->firmware);

        switch (props->usb_ctrl) {
                case CYPRESS_AN2135:
                case CYPRESS_AN2235:
                case CYPRESS_FX2:
                        ret = usb_cypress_load_firmware(udev, fw, props->usb_ctrl);
                        break;
                case DEVICE_SPECIFIC:
                        if (props->download_firmware)
                                ret = props->download_firmware(udev,fw);
                        else {
                                err("BUG: driver didn't specified a download_firmware-callback, although it claims to have a DEVICE_SPECIFIC one.");
                                ret = -EINVAL;
                        }
                        break;
                default:
                        ret = -EINVAL;
                        break;
        }

        release_firmware(fw);
        return ret;
}

int dvb_usb_get_hexline(const struct firmware *fw, struct hexline *hx,
                               int *pos)
{
        u8 *b = (u8 *) &fw->data[*pos];
        int data_offs = 4;
        if (*pos >= fw->size)
                return 0;

        memset(hx,0,sizeof(struct hexline));

        hx->len  = b[0];

        if ((*pos + hx->len + 4) >= fw->size)
                return -EINVAL;

        hx->addr = b[1] | (b[2] << 8);
        hx->type = b[3];

        if (hx->type == 0x04) {
                /* b[4] and b[5] are the Extended linear address record data field */
                hx->addr |= (b[4] << 24) | (b[5] << 16);
/*              hx->len -= 2;
                data_offs += 2; */
        }
        memcpy(hx->data,&b[data_offs],hx->len);
        hx->chk = b[hx->len + data_offs];

        *pos += hx->len + 5;

        return *pos;
}
EXPORT_SYMBOL(dvb_usb_get_hexline);