RT5575_SPI_BUF_LEN
u8 data[RT5575_SPI_BUF_LEN];
if (offset + RT5575_SPI_BUF_LEN <= len)
end = RT5575_SPI_BUF_LEN;
end = len % RT5575_SPI_BUF_LEN;
offset += RT5575_SPI_BUF_LEN;