The driver can match either via OF or ACPI ID tables. If one configuration is disabled, the table will be unused: drivers/nfc/st21nfca/i2c.c:593:34: warning: ‘of_st21nfca_i2c_match’ defined but not used [-Wunused-const-variable=] Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Link: https://lore.kernel.org/r/20210528124200.79655-11-krzysztof.kozlowski@canonical.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>