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charset=us-ascii Content-Disposition: inline In-Reply-To: <20261108-max31760-fixes-v1-3-a61450463059@gmail.com> X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-BWhitelist: no X-Source-IP: 108.223.40.66 X-Source-L: No X-Exim-ID: 1xQ5FO-00000000suh-0bYw X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 108-223-40-66.lightspeed.sntcca.sbcglobal.net (server.roeck-us.net) [108.223.40.66]:47254 X-Source-Auth: guenter@roeck-us.net X-Email-Count: 9 X-Org: HG=direseller_whb_net_legacy;ORG=directi; X-Source-Cap: cm9lY2s7YWN0aXZzdG07YmgtMjUud2ViaG9zdGJveC5uZXQ= X-Local-Domain: yes X-CMAE-Envelope: MS4xfJaC710AaxyfdqJ1ji14T5LO//pQbfLwrjKarVMdyBKloxR9DuyFESVWU5RIBrQPIadPrK6PpdSQ9jt94F+kIEuRbK8x/yPFx/9pRmuv0SEWcIXqjh27 LGdVc3owp0+R4RVs7oP0dN+U4xMWGxH3du6sNXKHgymR8tfRBLe1x6prXrsVI0xid0T7ZIXG81o5h+rB59A4KwzozusDM3qd/BFBNVItfLR0saHuzQxZhwZK On Sun, Nov 08, 2026 at 03:59:55AM +0000, Stanislav Aleksandrov wrote: > The tachometer count registers initialize to 0 until the first > measurement cycle completes after power-on. To prevent division by > zero, tach_to_rpm() clamped tach == 0 to 1, causing it to compute > and report 3,000,000 RPM (60 * 100000 / 1 / 2). > > Return 0 RPM when tach == 0 instead. > > Fixes: 38b04ad02d0d ("drivers: hwmon: Add max31760 fan speed controller driver") > Signed-off-by: Stanislav Aleksandrov Applied. Thanks, Guenter > --- > drivers/hwmon/max31760.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwmon/max31760.c b/drivers/hwmon/max31760.c > index e967555a21af..896bd0326b8c 100644 > --- a/drivers/hwmon/max31760.c > +++ b/drivers/hwmon/max31760.c > @@ -68,8 +68,9 @@ static const int max31760_pwm_freq[] = {33, 150, 1500, 25000}; > > static int tach_to_rpm(u16 tach) > { > + /* The count is 0 until the first measurement */ > if (tach == 0) > - tach = 1; > + return 0; > > return 60 * 100000 / tach / 2; > }