SP8870_FIRMWARE_OFFSET
if (fw->size < SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET)
fw_pos = SP8870_FIRMWARE_OFFSET;
while (fw_pos < SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET) {
tx_len = (fw_pos <= SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET - 252) ? 252 :
SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET - fw_pos;