static int ucd9000_probe()

in pmbus/ucd9000.c [490:615]

• 106 lines of code
• 24 McCabe index (conditional complexity)

static int ucd9000_probe(struct i2c_client *client)
{
	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
	struct ucd9000_data *data;
	struct pmbus_driver_info *info;
	const struct i2c_device_id *mid;
	enum chips chip;
	int i, ret;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_BYTE_DATA |
				     I2C_FUNC_SMBUS_BLOCK_DATA))
		return -ENODEV;

	ret = i2c_smbus_read_block_data(client, UCD9000_DEVICE_ID,
					block_buffer);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to read device ID\n");
		return ret;
	}
	block_buffer[ret] = '\0';
	dev_info(&client->dev, "Device ID %s\n", block_buffer);

	for (mid = ucd9000_id; mid->name[0]; mid++) {
		if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
			break;
	}
	if (!mid->name[0]) {
		dev_err(&client->dev, "Unsupported device\n");
		return -ENODEV;
	}

	if (client->dev.of_node)
		chip = (enum chips)of_device_get_match_data(&client->dev);
	else
		chip = mid->driver_data;

	if (chip != ucd9000 && strcmp(client->name, mid->name) != 0)
		dev_notice(&client->dev,
			   "Device mismatch: Configured %s, detected %s\n",
			   client->name, mid->name);

	data = devm_kzalloc(&client->dev, sizeof(struct ucd9000_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;
	info = &data->info;

	ret = i2c_smbus_read_byte_data(client, UCD9000_NUM_PAGES);
	if (ret < 0) {
		dev_err(&client->dev,
			"Failed to read number of active pages\n");
		return ret;
	}
	info->pages = ret;
	if (!info->pages) {
		dev_err(&client->dev, "No pages configured\n");
		return -ENODEV;
	}

	/* The internal temperature sensor is always active */
	info->func[0] = PMBUS_HAVE_TEMP;

	/* Everything else is configurable */
	ret = i2c_smbus_read_block_data(client, UCD9000_MONITOR_CONFIG,
					block_buffer);
	if (ret <= 0) {
		dev_err(&client->dev, "Failed to read configuration data\n");
		return -ENODEV;
	}
	for (i = 0; i < ret; i++) {
		int page = UCD9000_MON_PAGE(block_buffer[i]);

		if (page >= info->pages)
			continue;

		switch (UCD9000_MON_TYPE(block_buffer[i])) {
		case UCD9000_MON_VOLTAGE:
		case UCD9000_MON_VOLTAGE_HW:
			info->func[page] |= PMBUS_HAVE_VOUT
			  | PMBUS_HAVE_STATUS_VOUT;
			break;
		case UCD9000_MON_TEMPERATURE:
			info->func[page] |= PMBUS_HAVE_TEMP2
			  | PMBUS_HAVE_STATUS_TEMP;
			break;
		case UCD9000_MON_CURRENT:
			info->func[page] |= PMBUS_HAVE_IOUT
			  | PMBUS_HAVE_STATUS_IOUT;
			break;
		default:
			break;
		}
	}

	/* Fan configuration */
	if (mid->driver_data == ucd90124) {
		for (i = 0; i < UCD9000_NUM_FAN; i++) {
			i2c_smbus_write_byte_data(client,
						  UCD9000_FAN_CONFIG_INDEX, i);
			ret = i2c_smbus_read_block_data(client,
							UCD9000_FAN_CONFIG,
							data->fan_data[i]);
			if (ret < 0)
				return ret;
		}
		i2c_smbus_write_byte_data(client, UCD9000_FAN_CONFIG_INDEX, 0);

		info->read_byte_data = ucd9000_read_byte_data;
		info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12
		  | PMBUS_HAVE_FAN34 | PMBUS_HAVE_STATUS_FAN34;
	}

	ucd9000_probe_gpio(client, mid, data);

	ret = pmbus_do_probe(client, info);
	if (ret)
		return ret;

	ret = ucd9000_init_debugfs(client, mid, data);
	if (ret)
		dev_warn(&client->dev, "Failed to register debugfs: %d\n",
			 ret);

	return 0;
}