rockbox/firmware/target/arm/tms320dm320/sansa-connect/cryptomem-sansaconnect.c
Tomasz Moń b4ecd612f7
Sansa Connect: Use deviceid in USB Serial Number
Atmel AT88SC6416C CryptoMemory is almost I2C compatible. The device
is connected to bitbanged I2C bus shared with compliant I2C devices.

Change-Id: Iec54702db1bdfb93c01291eef18ec60391c63b16
2021-07-10 08:56:32 +02:00

80 lines
2.3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: $
*
* Copyright (C) 2021 by Tomasz Moń
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <ctype.h>
#include "cryptomem-sansaconnect.h"
#include "i2c-dm320.h"
/* Command values */
#define WRITE_USER_ZONE 0xB0
#define READ_USER_ZONE 0xB2
#define SYSTEM_WRITE 0xB4
#define SYSTEM_READ 0xB6
#define VERIFY_CRYPTO 0xB8
#define VERIFY_PASSWORD 0xBA
/* SYSTEM_WRITE ADDR 1 values */
#define WRITE_CONFIG 0x00
#define WRITE_FUSES 0x01
#define SEND_CHECKSUM 0x02
#define SET_USER_ZONE 0x03
int cryptomem_read_deviceid(char deviceid[32])
{
int ret;
unsigned int i;
unsigned char cmd_data[3];
/* It is assumed that other I2C communication has already taken place
* (e.g. power_init()) before this function is called and thus we don't
* have to send atleast 5 dummy clock cycles here.
*/
cmd_data[0] = SET_USER_ZONE;
cmd_data[1] = 0;
cmd_data[2] = 0;
ret = i2c_write(SYSTEM_WRITE, cmd_data, sizeof(cmd_data));
if (ret < 0)
{
return ret;
}
cmd_data[0] = 0;
cmd_data[1] = 0;
cmd_data[2] = 32;
ret = i2c_write_read_bytes(READ_USER_ZONE, cmd_data, sizeof(cmd_data),
deviceid, 32);
if (ret < 0)
{
return ret;
}
/* Verify that deviceid contains only printable ASCII characters */
for (i = 0; i < 32; i++)
{
if (!isprint(deviceid[i]))
{
return -1;
}
}
return 0;
}