r = container_of(attr, struct pcf2123_sysfs_reg, attr);
 
-       if (strict_strtoul(r->name, 16, ®))
-               return -EINVAL;
+       ret = kstrtoul(r->name, 16, ®);
+       if (ret)
+               return ret;
 
        txbuf[0] = PCF2123_READ | reg;
        ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1);
 
        r = container_of(attr, struct pcf2123_sysfs_reg, attr);
 
-       if (strict_strtoul(r->name, 16, ®)
-               || strict_strtoul(buffer, 10, &val))
-               return -EINVAL;
+       ret = kstrtoul(r->name, 16, ®);
+       if (ret)
+               return ret;
+
+       ret = kstrtoul(buffer, 10, &val);
+       if (ret)
+               return ret;
 
        txbuf[0] = PCF2123_WRITE | reg;
        txbuf[1] = val;