Re: [PATCH] mfd: wm8350: propagate ADC read timeout instead of returning 0
Guenter Roeck <[email protected]> Tue, 4 Aug 2026 20:00:39 -0700
| Newsgroups | org.kernel.vger.linux-hwmon,dev.linux.lists.mfd,org.kernel.vger.linux-kernel,org.kernel.vger.linux-pm |
|---|---|
| Message-ID | <[email protected]> |
On 8/4/26 18:42, Ivy Lopez wrote: > wm8350_read_auxadc() logs an error via dev_err() when the AUX ADC > read times out, but then falls through to return the masked value > of `result`, which was left at its initial value of 0. Callers have > no way to distinguish a genuine 0V reading from a failed read. > > Return -ETIMEDOUT on timeout instead, and update the wm8350 hwmon > and power_supply drivers, which call this function directly, to > check for a negative return and propagate the error rather than > using it as a voltage value. > I am not sure if this warrants fixing in a 17+ year old driver, unless it is observed to be a real problem. It appears to me that the error handling was likely not implemented on purpose. On top of that, as is seen a lot lately, this fixes a rare issue that is likely never going to be seen in the real world while not addressing the many real problems in the driver (as reported by Sashiko). Guenter