Re: [PATCH v3 1/2] dt-bindings: media: i2c: dongwoon,dw9714: Document DW9714A and V variant
From: David Heidelberg
Date: Thu Aug 27 2026 - 06:20:05 EST
On 26/08/2026 22:13, Sakari Ailus wrote:
Hi David,
On Mon, Aug 10, 2026 at 12:24:58PM +0200, David Heidelberg wrote:
On 10/08/2026 11:38, Sakari Ailus wrote:
Hi David,
On Mon, Aug 03, 2026 at 11:50:25AM +0200, David Heidelberg via B4 Relay wrote:
From: David Heidelberg <david@xxxxxxx>
DW9714A is successor of DW9714 and DW9714V is successor of the DW9714A.
All actuators are backward compatible, but they do introduce new features,
such as Smart Actuator Control (SAC) mode which can minimize the
mechanical vibration and achieve very fast mechanical settling time.
Support for SAC can be implemented in the future.
What kind of configuration does SAC require? Such things generally aren't
configured from the userspace, compare e.g. with the dw9719 bindings
discussion.
I don't have extra deep insight (except basic how the sensor works).
By default all dw9714* sensors starts in the default "legacy" mode.
The clanker after looking at datasheets and kernel struct produced, if it
make sense:
the mode and the vibration period (SAC_CFG/PRESC/SACT) have to match
the mechanical tVIB of the actuator and lens assembly of the given camera
module, the same way dongwoon,aac-mode/aac-timing/clock-presc do for
dongwoon,dw9768 and dongwoon,sac-mode/vcm-prescale for dongwoon,dw9719.
Those properties are left out until there is driver support and measured
values; note the DW9714V mode set differs from DW9719's, so its enum cannot
be reused as is.
I guess this is fine, but without the configuration there's not much
benefit knowing the VCM is actually a bit more sophisticated one.
Yes, definitely. I just wanted to use proper compatible from the start.
I plan to dive into it deeper when libcamera integrates the AF, as for now doing extra work here has not many benefits.
David