Re: [PATCH net-next v3 2/2] dpll: use pin owner's dpll ref for pin-level attribute setting
From: Jiri Pirko
Date: Sat Aug 08 2026 - 06:00:36 EST
Fri, Aug 07, 2026 at 11:59:26AM +0200, ivecera@xxxxxxxxxx wrote:
>Pin-level attributes (frequency, phase adjust, embedded sync, reference
>sync) are properties of the pin itself, not of a particular DPLL device.
>The get callbacks already use only the pin owner's DPLL reference
>(via dpll_pin_own_dpll_ref_first()), but the set callbacks iterate over
>all registered DPLL references and invoke the set operation on each one.
>
>This is redundant because a pin is a single physical entity - setting
>its frequency or phase adjust once through the owner's ops is sufficient.
>Calling set on every registered DPLL just results in duplicate HW writes
>for drivers that share a pin across multiple DPLL devices (e.g. ice
>registers each input pin with both the EEC and PPS DPLL, zl3073x
>registers input pins with every DPLL channel).
>
>Simplify dpll_pin_freq_set(), dpll_pin_esync_set(),
>dpll_pin_ref_sync_state_set() and dpll_pin_phase_adj_set() to call the
>set callback only through the owner's DPLL reference, matching the
>existing get-side behavior. This removes the xa_for_each iteration
>loops, the now-unnecessary rollback logic, and several local variables.
>
>The -EOPNOTSUPP validation loop, which checked ops support across all
>owner-matching references, is replaced with a direct check on the
>single owner reference returned by dpll_pin_own_dpll_ref_first().
>
>The documentation in dpll.rst is updated to reflect that pin-level
>attributes are set through the pin owner's dpll reference only.
>
>No existing driver is affected:
> - ptp_ocp and mlx5 register each pin with a single DPLL.
> - ice registers input pins with two DPLLs (EEC and PPS) using
> identical ops and pin_priv; the set callbacks address the HW by
> pin index, not by DPLL, so the second call was a no-op.
> - zl3073x registers input pins with every DPLL channel; the set
> callbacks address HW by pin/ref ID regardless of DPLL. The
> ref_sync_set callback was the only one with per-channel behavior,
> addressed by the preceding patch.
>
>Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>
Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx>