static int fsi_slave_scan()

in fsi-core.c [466:551]

• 61 lines of code
• 9 McCabe index (conditional complexity)

static int fsi_slave_scan(struct fsi_slave *slave)
{
	uint32_t engine_addr;
	int rc, i;

	/*
	 * scan engines
	 *
	 * We keep the peek mode and slave engines for the core; so start
	 * at the third slot in the configuration table. We also need to
	 * skip the chip ID entry at the start of the address space.
	 */
	engine_addr = engine_page_size * 3;
	for (i = 2; i < engine_page_size / sizeof(uint32_t); i++) {
		uint8_t slots, version, type, crc;
		struct fsi_device *dev;
		uint32_t conf;
		__be32 data;

		rc = fsi_slave_read(slave, (i + 1) * sizeof(data),
				&data, sizeof(data));
		if (rc) {
			dev_warn(&slave->dev,
				"error reading slave registers\n");
			return -1;
		}
		conf = be32_to_cpu(data);

		crc = crc4(0, conf, 32);
		if (crc) {
			dev_warn(&slave->dev,
				"crc error in slave register at 0x%04x\n",
				i);
			return -1;
		}

		slots = (conf & FSI_SLAVE_CONF_SLOTS_MASK)
			>> FSI_SLAVE_CONF_SLOTS_SHIFT;
		version = (conf & FSI_SLAVE_CONF_VERSION_MASK)
			>> FSI_SLAVE_CONF_VERSION_SHIFT;
		type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
			>> FSI_SLAVE_CONF_TYPE_SHIFT;

		/*
		 * Unused address areas are marked by a zero type value; this
		 * skips the defined address areas
		 */
		if (type != 0 && slots != 0) {

			/* create device */
			dev = fsi_create_device(slave);
			if (!dev)
				return -ENOMEM;

			dev->slave = slave;
			dev->engine_type = type;
			dev->version = version;
			dev->unit = i;
			dev->addr = engine_addr;
			dev->size = slots * engine_page_size;

			dev_dbg(&slave->dev,
			"engine[%i]: type %x, version %x, addr %x size %x\n",
					dev->unit, dev->engine_type, version,
					dev->addr, dev->size);

			dev_set_name(&dev->dev, "%02x:%02x:%02x:%02x",
					slave->master->idx, slave->link,
					slave->id, i - 2);
			dev->dev.of_node = fsi_device_find_of_node(dev);

			rc = device_register(&dev->dev);
			if (rc) {
				dev_warn(&slave->dev, "add failed: %d\n", rc);
				put_device(&dev->dev);
			}
		}

		engine_addr += slots * engine_page_size;

		if (!(conf & FSI_SLAVE_CONF_NEXT_MASK))
			break;
	}

	return 0;
}