void jtag_shift_data()

in common/util/hal_jtag.c [31:97]

• 58 lines of code
• 12 McCabe index (conditional complexity)

void jtag_shift_data(uint16_t Wbit, uint8_t *Wdate, uint16_t Rbit, uint8_t *Rdate, uint8_t lastidx)
{
	const struct device *dev;
	dev = device_get_binding(jtag_device);
	if (!dev) {
		printf("JTAG device not found\n");
		return;
	}

	uint8_t value, tdo_val, TMS_val = 0;
	uint16_t RnWbit, RnWbyte, index;

	RnWbit = (Wbit > Rbit) ? Wbit : Rbit;
	RnWbyte = (RnWbit + 7) >> 3;

	for (index = 0; index < RnWbit; index++) {
		if ((Wbit != 0) && (Rbit != 0)) {
			value = Wdate[index / 8] & 0x01;
			if ((Wbit == 1) && (Rbit == 1)) {
				TMS_val = lastidx;
			}

			jtag_sw_xfer(dev, JTAG_TCK, 0);
			jtag_sw_xfer(dev, JTAG_TDI, value);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);
			jtag_sw_xfer(dev, JTAG_TCK, 1);
			jtag_sw_xfer(dev, JTAG_TDI, value);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);
			jtag_tdo_get(dev, &tdo_val);

			Wdate[index / 8] = Wdate[index / 8] >> 1;
			Rdate[index / 8] |= tdo_val << index % 8;
			Wbit--;
			Rbit--;
		} else if (Wbit != 0) {
			value = Wdate[index / 8] & 0x01;
			if ((Wbit == 1)) {
				TMS_val = lastidx;
			}

			jtag_sw_xfer(dev, JTAG_TCK, 0);
			jtag_sw_xfer(dev, JTAG_TDI, value);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);
			jtag_sw_xfer(dev, JTAG_TCK, 1);
			jtag_sw_xfer(dev, JTAG_TDI, value);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);

			Wdate[index / 8] = Wdate[index / 8] >> 1;
			Wbit--;
		} else if (Rbit != 0) {
			if ((Rbit == 1)) {
				TMS_val = lastidx;
			}

			jtag_sw_xfer(dev, JTAG_TCK, 0);
			jtag_sw_xfer(dev, JTAG_TDI, 0);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);
			jtag_sw_xfer(dev, JTAG_TCK, 1);
			jtag_sw_xfer(dev, JTAG_TDI, 0);
			jtag_sw_xfer(dev, JTAG_TMS, TMS_val);
			jtag_tdo_get(dev, &tdo_val);

			Rdate[index / 8] |= tdo_val << index % 8;
			Rbit--;
		}
	}
}