Re: [PATCH v7 4/4] hwmon: pmbus: mpq8646: gate the writes

Guenter Roeck <[email protected]> Fri, 31 Jul 2026 07:31:51 -0700

Newsgroups	org.kernel.vger.linux-hwmon,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-doc,org.kernel.vger.linux-kernel
Message-ID	<[email protected]>

On Thu, Jul 30, 2026 at 05:44:02PM +0200, Vincent Jardin wrote:
> From: Vincent Jardin <[email protected]>
> 
> The write cases of debugfs entries are provisioning and bench
> helpers. By designs the MPQ8646 powers the CPU core rail,
> so a wrong write can brown out the board or persist a bad
> setpoint into finite-cycle NVM.
> Said differently: some wrong register writes can and likely
> will physically damage or destroy the chip and/or the board.
> 
> To be safe, it is disabled by default behind a
> CONFIG_SENSORS_MPQ8646_DEBUG_UNSAFE and we print an explicit warning
> banner at probe time when they are built in.
> 
> Signed-off-by: Vincent Jardin <[email protected]>

Applied.

Thanks,
Guenter