Re: [PATCH v4 0/3] hwmon: (pmbus/adm1266) add clear_blackbox and powerup_counter debugfs entries

[Guenter Roeck]

Hi,

On 5/16/26 18:18, Abdurrahman Hussain wrote:
> This is what remains of the v3 series after Guenter applied patches
> 1/5 (firmware_revision) and 5/5 (GPIO line label) to hwmon-next, and
> asked for patch 4/5 (rtc_class) to be dropped.
>
> Patch 1 adds a write-only clear_blackbox debugfs file. Devices
> configured for single-recording mode (BLACKBOX_CONFIG[0] = 0) need
> an explicit clear once the 32-record buffer fills; the documented
> sub-command ({0xFE, 0x00} block-write to 0xDE) wasn't reachable
> from userspace. The patch also acquires pmbus_lock at the
> adm1266_nvmem_read() callback boundary so the memset of
> data->dev_mem, the blackbox refill, and the memcpy to userspace run
> as a single critical section -- the nvmem core does not serialize
> concurrent reg_read calls.
>
> Patch 2 exposes the non-volatile POWERUP_COUNTER (0xE4) via debugfs.
> The same value is embedded in every blackbox record, so the live
> value lets userspace match a captured record back to the boot it
> came from when correlating logs. The block-read is taken under
> pmbus_lock to serialise against any pmbus_core PAGE+register
> sequence on the device.
>
> Patch 3 takes pmbus_lock in adm1266_state_read() (the pre-existing
> sequencer_state debugfs handler) for the same defensive-locking
> reason that motivates the new debugfs files in patches 1 and 2:
> any direct device access from outside pmbus_core should be ordered
> with respect to pmbus_core's own PAGE+register sequences.
>
> Signed-off-by: Abdurrahman Hussain <abdurrahman@xxxxxxxxxx>

The series no longer applies after applying the bug fix series.
Please rebase it on top of the hwmon-next branch of
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git
and resubmit.

Sorry for the trouble, and thanks a lot for fixing all the problems
with the driver.

Guenter