	/* parameter format: pins=cs_pin:sck_pin:mosi_pin:miso_pin */
	char *pins = extract_programmer_param("pins");
	int pins_inited = 0;
	do {
		struct pin_desc *pins_tab[] = {
			&pin_cs, &pin_sck, &pin_mosi, &pin_miso
		};
		if (!(pins && strlen(pins)))
			break;
		char *token = strtok(pins, ":");
		for (unsigned i = 0; i < ARRAY_SIZE(pins_tab); i++) {
			long v;
			if (!token)
				break;
			if (atoi_s(token, 1, &v))
				break;
			pins_tab[i]->pin = v;
			if (export_sysfsgpio(pins_tab[i]))
				break;
			token = strtok(NULL, ":");
			pins_inited = (i + 1 == ARRAY_SIZE(pins_tab));
		}
	} while (0);
	if (pins)
		free(pins);
	if (!pins_inited)
		return 1;