void pal_usb_handler()

in meta-facebook/yv35-cl/src/ipmi/usb_ipmi.c [12:78]
60 lines of code
10 McCabe index (conditional complexity)

void pal_usb_handler(uint8_t *rx_buff, int rx_len)
{
	uint16_t record_offset;
	static ipmi_msg_cfg current_msg;
	static bool fwupdate_keep_data = 0;
	static uint16_t keep_data_len = 0;
	static uint16_t fwupdate_data_len = 0;

	if (DEBUG_USB) {
		printk("USB: len %d, req: %x %x ID: %x %x %x target: %x offset: %x %x %x %x len: %x %x\n",
		       rx_len, rx_buff[0], rx_buff[1], rx_buff[2], rx_buff[3], rx_buff[4],
		       rx_buff[5], rx_buff[6], rx_buff[7], rx_buff[8], rx_buff[9], rx_buff[10],
		       rx_buff[11]);
	}

	// USB driver must receive 64 byte package from bmc
	// it takes 512 + 64 byte package to receive ipmi command + 512 byte image data
	// if cmd fw_update, record next usb package as image until receive complete data
	if ((rx_buff[0] == (NETFN_OEM_1S_REQ << 2)) && (rx_buff[1] == CMD_OEM_1S_FW_UPDATE)) {
		fwupdate_keep_data = true;
	}

	if (fwupdate_keep_data) {
		if ((keep_data_len + rx_len) > IPMI_DATA_MAX_LENGTH) {
			printk("usb fw update recv data over ipmi buff size %d, keep %d, recv %d\n",
			       IPMI_DATA_MAX_LENGTH, keep_data_len, rx_len);
			keep_data_len = 0;
			fwupdate_keep_data = false;
			return;
		} else if (!keep_data_len) { // only fill up ipmb buffer from first package
			current_msg.buffer.netfn = rx_buff[0] >> 2;
			current_msg.buffer.cmd = rx_buff[1];
			current_msg.buffer.InF_source = BMC_USB_IFs;
			current_msg.buffer.data_len = rx_len - SIZE_NETFN_CMD;
			fwupdate_data_len = ((rx_buff[11] << 8) | rx_buff[10]);
			memcpy(&current_msg.buffer.data[0], &rx_buff[SIZE_NETFN_CMD],
			       (rx_len - SIZE_NETFN_CMD));
			keep_data_len = rx_len - FWUPDATE_HEADER_SIZE;
		} else {
			record_offset = keep_data_len + FWUPDATE_HEADER_SIZE - SIZE_NETFN_CMD;
			memcpy(&current_msg.buffer.data[record_offset], &rx_buff[0], rx_len);
			current_msg.buffer.data_len += rx_len;
			keep_data_len += rx_len;
		}
		if (keep_data_len == fwupdate_data_len) {
			while (k_msgq_put(&ipmi_msgq, &current_msg, K_NO_WAIT) != 0) {
				k_msgq_purge(&ipmi_msgq);
				printf("KCS retrying put ipmi msgq\n");
			}
			keep_data_len = 0;
			fwupdate_data_len = 0;
			fwupdate_keep_data = false;
		}
	} else {
		current_msg.buffer.netfn = rx_buff[0] >> 2;
		current_msg.buffer.cmd = rx_buff[1];
		current_msg.buffer.InF_source = BMC_USB_IFs;
		current_msg.buffer.data_len = rx_len - SIZE_NETFN_CMD;
		memcpy(&current_msg.buffer.data[0], &rx_buff[2], current_msg.buffer.data_len);
		while (k_msgq_put(&ipmi_msgq, &current_msg, K_NO_WAIT) != 0) {
			k_msgq_purge(&ipmi_msgq);
			printf("KCS retrying put ipmi msgq\n");
		}
	}

	return;
}