From: Denis Pauk <pauk.denis@gmail.com>
Date: Sat, 18 Dec 2021 20:52:06 +0000 (+0200)
Subject: hwmon: (nct6775) Additional check for ChipID before ASUS WMI usage
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=20f2e67cbc7599217d5a764c76e9c2bbe85e3761;p=linux.git

hwmon: (nct6775) Additional check for ChipID before ASUS WMI usage

WMI monitoring methods can be changed or removed in new ASUS boards
BIOS versions. Such versions return zero instead of a real one as
Chip ID.

Commit adds additional validation for the result of Chip ID call
before enabling access by ASUS WMI methods.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=204807
Signed-off-by: Denis Pauk <pauk.denis@gmail.com>
Link: https://lore.kernel.org/r/20211218205206.615865-1-pauk.denis@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---

diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c
index c58538246cc8e..fd3f91cb01c6a 100644
--- a/drivers/hwmon/nct6775.c
+++ b/drivers/hwmon/nct6775.c
@@ -5038,7 +5038,7 @@ static int __init sensors_nct6775_init(void)
 				   board_name);
 		if (err >= 0) {
 			/* if reading chip id via WMI succeeds, use WMI */
-			if (!nct6775_asuswmi_read(0, NCT6775_PORT_CHIPID, &tmp)) {
+			if (!nct6775_asuswmi_read(0, NCT6775_PORT_CHIPID, &tmp) && tmp) {
 				pr_info("Using Asus WMI to access %#x chip.\n", tmp);
 				access = access_asuswmi;
 			} else {