platform: mips: cpu_hwmon: Disable driver on unsupported hardware

cpu_hwmon is unsupported on CPUs without loongson_chiptemp
register and csr.

Cc: stable@vger.kernel.org
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

diff --git a/drivers/platform/mips/cpu_hwmon.c b/drivers/platform/mips/cpu_hwmon.c
index d8c5f9195f85f5d436a4065aee16a380627ba50a..2ac2f31090f96fd34ba070989b3aadd0a48e0914 100644 (file)
--- a/drivers/platform/mips/cpu_hwmon.c
+++ b/drivers/platform/mips/cpu_hwmon.c
@@ -139,6 +139,9 @@ static int __init loongson_hwmon_init(void)
                csr_temp_enable = csr_readl(LOONGSON_CSR_FEATURES) &
                                  LOONGSON_CSRF_TEMP;
 
+       if (!csr_temp_enable && !loongson_chiptemp[0])
+               return -ENODEV;
+
        nr_packages = loongson_sysconf.nr_cpus /
                loongson_sysconf.cores_per_package;