From 31d43648cf0e0d9f700132a2178711221a033fcf Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Wed, 3 Aug 2016 22:07:18 -0700 Subject: [PATCH] hwmon: (nct6775) Do not accept force_id unless chip is found Since commit 698a7c24a544 ("hwmon: (nct6775) Support two SuperIO chips in the same system"), the driver supports two Super-IO chips. This has the undesirable side effect that force_id always detects a second chip at address 0xfff8, even if no chip exists at that address. nct6775: Found NCT6793D or compatible chip at 0x4e:0xfff8 If no chip at all is found at a given SIO address, it does not make sense to instantiate it. Limit force_id to only work if some chip is found, that is if the chip ID returns a value other than 0xffff. Signed-off-by: Guenter Roeck --- nct6775.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/nct6775.c b/nct6775.c index 36cd1e4..068fb9b 100644 --- a/nct6775.c +++ b/nct6775.c @@ -4277,11 +4277,11 @@ static int __init nct6775_find(int sioaddr, struct nct6775_sio_data *sio_data) if (err) return err; - if (force_id) + val = (superio_inb(sioaddr, SIO_REG_DEVID) << 8) | + superio_inb(sioaddr, SIO_REG_DEVID + 1); + if (force_id && val != 0xffff) val = force_id; - else - val = (superio_inb(sioaddr, SIO_REG_DEVID) << 8) - | superio_inb(sioaddr, SIO_REG_DEVID + 1); + switch (val & SIO_ID_MASK) { case SIO_NCT6106_ID: sio_data->kind = nct6106; -- 2.39.2