MSP430F5xxx infomem flasher

flash.c

/* Simple F5xxx Flash Erase/Write primitives
 * 2014 Eric Brundick <spirilis@linux.com>
 */
#include <msp430.h>
#include <stdint.h>
#include <stdbool.h>
#include "flash.h"

int flash_erase_info(void *loc)
{
    WDTCTL = WDTPW | WDTHOLD;

    while (FCTL3 & BUSY) ;

    FCTL3 = FWPW;  // Clear LOCK
    FCTL4 = FWPW;  // Clear LOCKINFO
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    FCTL1 = FWPW | ERASE;  // Enable Segment Erase
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    *((uint8_t *)loc) = 0;  // Dummy write to Flash segment
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    while (FCTL3 & BUSY) ;  // Wait for completion

    FCTL3 = FWPW | LOCK;  // Set LOCK
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    return 0;
}

int flash_write_unlock()
{
    WDTCTL = WDTPW | WDTHOLD;

    while (FCTL3 & BUSY)
        ;

    FCTL3 = FWPW;  // Clear LOCK
    FCTL4 = FWPW;  // Clear LOCKINFO
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    FCTL1 = FWPW | WRT;  // Enable write
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    return 0;
}

int flash_write_lock()
{
    while (FCTL3 & BUSY)
        ;

    FCTL1 = FWPW;
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    FCTL3 = FWPW | LOCK;
    FCTL4 = FWPW | LOCKINFO;
    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    return 0;
}

int flash_write_word(void *loc, uint16_t val)
{
    if (!(FCTL4 & LOCKINFO)) {
        *((uint16_t *)loc) = val;
        while (!(FCTL3 & WAIT)) ;
    } else {
        return -2;
    }

    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    return 0;
}

int flash_write_byte(void *loc, uint8_t val)
{
    if (!(FCTL4 & LOCKINFO)) {
        *((uint8_t *)loc) = val;
        while (!(FCTL3 & WAIT)) ;
    } else {
        return -2;
    }

    if (FCTL3 & (KEYV|ACCVIFG))
        return -1;

    return 0;
}

flash.h

/* Simple F5xxx Flash Erase/Write primitives
 * 2014 Eric Brundick <spirilis@linux.com>
 */

#ifndef FLASH_H
#define FLASH_H

#include <msp430.h>
#include <stdint.h>

int flash_erase_info(void *loc);
int flash_write_unlock();
int flash_write_lock();
int flash_write_word(void *loc, uint16_t val);
int flash_write_byte(void *loc, uint8_t val);

#endif