emi62.c

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/* 
 * Emagic EMI 2|6 usb audio interface firmware loader.
 * Copyright (C) 2002
 *  Tapio Laxström ([email protected])
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, as published by
 * the Free Software Foundation, version 2.
 */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/ihex.h>

/* include firmware (variables)*/

/* FIXME: This is quick and dirty solution! */
#define SPDIF   /* if you want SPDIF comment next line */
//#undef SPDIF  /* if you want MIDI uncomment this line */ 

#ifdef SPDIF
#define FIRMWARE_FW "emi62/spdif.fw"
#else
#define FIRMWARE_FW "emi62/midi.fw"
#endif

#define EMI62_VENDOR_ID         0x086a  /* Emagic Soft-und Hardware GmBH */
#define EMI62_PRODUCT_ID        0x0110  /* EMI 6|2m without firmware */

#define ANCHOR_LOAD_INTERNAL    0xA0    /* Vendor specific request code for Anchor Upload/Download (This one is implemented in the core) */
#define ANCHOR_LOAD_EXTERNAL    0xA3    /* This command is not implemented in the core. Requires firmware */
#define ANCHOR_LOAD_FPGA    0xA5    /* This command is not implemented in the core. Requires firmware. Emagic extension */
#define MAX_INTERNAL_ADDRESS    0x1B3F  /* This is the highest internal RAM address for the AN2131Q */
#define CPUCS_REG       0x7F92  /* EZ-USB Control and Status Register.  Bit 0 controls 8051 reset */ 
#define INTERNAL_RAM(address)   (address <= MAX_INTERNAL_ADDRESS)

static int emi62_writememory(struct usb_device *dev, int address,
                 const unsigned char *data, int length,
                 __u8 bRequest);
static int emi62_set_reset(struct usb_device *dev, unsigned char reset_bit);
static int emi62_load_firmware (struct usb_device *dev);
static int emi62_probe(struct usb_interface *intf, const struct usb_device_id *id);
static void emi62_disconnect(struct usb_interface *intf);

/* thanks to drivers/usb/serial/keyspan_pda.c code */
static int emi62_writememory(struct usb_device *dev, int address,
                 const unsigned char *data, int length,
                 __u8 request)
{
    int result;
    unsigned char *buffer =  kmemdup(data, length, GFP_KERNEL);

    if (!buffer) {
        dev_err(&dev->dev, "kmalloc(%d) failed.\n", length);
        return -ENOMEM;
    }
    /* Note: usb_control_msg returns negative value on error or length of the
     *       data that was written! */
    result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300);
    kfree (buffer);
    return result;
}

/* thanks to drivers/usb/serial/keyspan_pda.c code */
static int emi62_set_reset (struct usb_device *dev, unsigned char reset_bit)
{
    int response;
    dev_info(&dev->dev, "%s - %d\n", __func__, reset_bit);
    
    response = emi62_writememory (dev, CPUCS_REG, &reset_bit, 1, 0xa0);
    if (response < 0)
        dev_err(&dev->dev, "set_reset (%d) failed\n", reset_bit);
    return response;
}

#define FW_LOAD_SIZE        1023

static int emi62_load_firmware (struct usb_device *dev)
{
    const struct firmware *loader_fw = NULL;
    const struct firmware *bitstream_fw = NULL;
    const struct firmware *firmware_fw = NULL;
    const struct ihex_binrec *rec;
    int err = -ENOMEM;
    int i;
    __u32 addr; /* Address to write */
    __u8 *buf;

    dev_dbg(&dev->dev, "load_firmware\n");
    buf = kmalloc(FW_LOAD_SIZE, GFP_KERNEL);
    if (!buf)
        goto wraperr;

    err = request_ihex_firmware(&loader_fw, "emi62/loader.fw", &dev->dev);
    if (err)
        goto nofw;

    err = request_ihex_firmware(&bitstream_fw, "emi62/bitstream.fw",
                    &dev->dev);
    if (err)
        goto nofw;

    err = request_ihex_firmware(&firmware_fw, FIRMWARE_FW, &dev->dev);
    if (err) {
    nofw:
        goto wraperr;
    }

    /* Assert reset (stop the CPU in the EMI) */
    err = emi62_set_reset(dev,1);
    if (err < 0)
        goto wraperr;

    rec = (const struct ihex_binrec *)loader_fw->data;

    /* 1. We need to put the loader for the FPGA into the EZ-USB */
    while (rec) {
        err = emi62_writememory(dev, be32_to_cpu(rec->addr),
                    rec->data, be16_to_cpu(rec->len),
                    ANCHOR_LOAD_INTERNAL);
        if (err < 0)
            goto wraperr;
        rec = ihex_next_binrec(rec);
    }

    /* De-assert reset (let the CPU run) */
    err = emi62_set_reset(dev,0);
    if (err < 0)
        goto wraperr;
    msleep(250);    /* let device settle */

    /* 2. We upload the FPGA firmware into the EMI
     * Note: collect up to 1023 (yes!) bytes and send them with
     * a single request. This is _much_ faster! */
    rec = (const struct ihex_binrec *)bitstream_fw->data;
    do {
        i = 0;
        addr = be32_to_cpu(rec->addr);

        /* intel hex records are terminated with type 0 element */
        while (rec && (i + be16_to_cpu(rec->len) < FW_LOAD_SIZE)) {
            memcpy(buf + i, rec->data, be16_to_cpu(rec->len));
            i += be16_to_cpu(rec->len);
            rec = ihex_next_binrec(rec);
        }
        err = emi62_writememory(dev, addr, buf, i, ANCHOR_LOAD_FPGA);
        if (err < 0)
            goto wraperr;
    } while (rec);

    /* Assert reset (stop the CPU in the EMI) */
    err = emi62_set_reset(dev,1);
    if (err < 0)
        goto wraperr;

    /* 3. We need to put the loader for the firmware into the EZ-USB (again...) */
    for (rec = (const struct ihex_binrec *)loader_fw->data;
         rec; rec = ihex_next_binrec(rec)) {
        err = emi62_writememory(dev, be32_to_cpu(rec->addr),
                    rec->data, be16_to_cpu(rec->len),
                    ANCHOR_LOAD_INTERNAL);
        if (err < 0)
            goto wraperr;
    }

    /* De-assert reset (let the CPU run) */
    err = emi62_set_reset(dev,0);
    if (err < 0)
        goto wraperr;
    msleep(250);    /* let device settle */

    /* 4. We put the part of the firmware that lies in the external RAM into the EZ-USB */

    for (rec = (const struct ihex_binrec *)firmware_fw->data;
         rec; rec = ihex_next_binrec(rec)) {
        if (!INTERNAL_RAM(be32_to_cpu(rec->addr))) {
            err = emi62_writememory(dev, be32_to_cpu(rec->addr),
                        rec->data, be16_to_cpu(rec->len),
                        ANCHOR_LOAD_EXTERNAL);
            if (err < 0)
                goto wraperr;
        }
    }

    /* Assert reset (stop the CPU in the EMI) */
    err = emi62_set_reset(dev,1);
    if (err < 0)
        goto wraperr;

    for (rec = (const struct ihex_binrec *)firmware_fw->data;
         rec; rec = ihex_next_binrec(rec)) {
        if (INTERNAL_RAM(be32_to_cpu(rec->addr))) {
            err = emi62_writememory(dev, be32_to_cpu(rec->addr),
                        rec->data, be16_to_cpu(rec->len),
                        ANCHOR_LOAD_EXTERNAL);
            if (err < 0)
                goto wraperr;
        }
    }

    /* De-assert reset (let the CPU run) */
    err = emi62_set_reset(dev,0);
    if (err < 0)
        goto wraperr;
    msleep(250);    /* let device settle */

    release_firmware(loader_fw);
    release_firmware(bitstream_fw);
    release_firmware(firmware_fw);

    kfree(buf);

    /* return 1 to fail the driver inialization
     * and give real driver change to load */
    return 1;

wraperr:
    if (err < 0)
        dev_err(&dev->dev,"%s - error loading firmware: error = %d\n",
            __func__, err);
    release_firmware(loader_fw);
    release_firmware(bitstream_fw);
    release_firmware(firmware_fw);

    kfree(buf);
    dev_err(&dev->dev, "Error\n");
    return err;
}

static const struct usb_device_id id_table[] = {
    { USB_DEVICE(EMI62_VENDOR_ID, EMI62_PRODUCT_ID) },
    { }                                             /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, id_table);

static int emi62_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
    struct usb_device *dev = interface_to_usbdev(intf);
    dev_dbg(&intf->dev, "emi62_probe\n");

    dev_info(&intf->dev, "%s start\n", __func__);

    emi62_load_firmware(dev);

    /* do not return the driver context, let real audio driver do that */
    return -EIO;
}

static void emi62_disconnect(struct usb_interface *intf)
{
}

static struct usb_driver emi62_driver = {
    .name       = "emi62 - firmware loader",
    .probe      = emi62_probe,
    .disconnect = emi62_disconnect,
    .id_table   = id_table,
};

module_usb_driver(emi62_driver);

MODULE_AUTHOR("Tapio Laxström");
MODULE_DESCRIPTION("Emagic EMI 6|2m firmware loader.");
MODULE_LICENSE("GPL");

MODULE_FIRMWARE("emi62/loader.fw");
MODULE_FIRMWARE("emi62/bitstream.fw");
MODULE_FIRMWARE(FIRMWARE_FW);
/* vi:ai:syntax=c:sw=8:ts=8:tw=80
 */