BQ27XXX_DM_DATA
ret = bq27xxx_read_block(di, BQ27XXX_DM_DATA, buf->data, BQ27XXX_DM_SZ);
[BQ27XXX_DM_DATA] = 0x40, \
ret = bq27xxx_write_block(di, BQ27XXX_DM_DATA, buf->data, BQ27XXX_DM_SZ);
[BQ27XXX_DM_DATA] = INVALID_REG_ADDR,
[BQ27XXX_DM_DATA] = INVALID_REG_ADDR,
[BQ27XXX_DM_DATA] = INVALID_REG_ADDR,