static int trf7970a_in_config_framing()

in trf7970a.c [1263:1336]

• 62 lines of code
• 22 McCabe index (conditional complexity)

static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
{
	u8 iso_ctrl = trf->iso_ctrl_tech;
	bool is_rf_field = false;
	int ret;

	dev_dbg(trf->dev, "framing: %d\n", framing);

	switch (framing) {
	case NFC_DIGITAL_FRAMING_NFCA_SHORT:
	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
		break;
	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
	case NFC_DIGITAL_FRAMING_NFCA_T4T:
	case NFC_DIGITAL_FRAMING_NFCB:
	case NFC_DIGITAL_FRAMING_NFCB_T4T:
	case NFC_DIGITAL_FRAMING_NFCF:
	case NFC_DIGITAL_FRAMING_NFCF_T3T:
	case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
	case NFC_DIGITAL_FRAMING_ISO15693_T5T:
	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
		break;
	case NFC_DIGITAL_FRAMING_NFCA_T2T:
		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
		break;
	default:
		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
		return -EINVAL;
	}

	trf->framing = framing;

	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
		ret = trf7970a_is_rf_field(trf, &is_rf_field);
		if (ret)
			return ret;

		if (is_rf_field)
			return -EBUSY;
	}

	if (iso_ctrl != trf->iso_ctrl) {
		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
		if (ret)
			return ret;

		trf->iso_ctrl = iso_ctrl;

		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
				     trf->modulator_sys_clk_ctrl);
		if (ret)
			return ret;
	}

	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
				     trf->chip_status_ctrl |
				     TRF7970A_CHIP_STATUS_RF_ON);
		if (ret)
			return ret;

		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;

		usleep_range(trf->guard_time, trf->guard_time + 1000);
	}

	return 0;
}