Re: [PATCH v3 1/2] dt-bindings: HID: i2c-hid: Document reset-related properties

From: Rob Herring
Date: Wed Jan 31 2024 - 15:22:53 EST


On Mon, Jan 29, 2024 at 05:56:47PM +0100, Johan Hovold wrote:
> On Mon, Jan 29, 2024 at 08:47:47AM -0800, Bjorn Andersson wrote:
> > Some I2C HID devices has a reset pin and requires that some specified
> > time elapses after this reset pin is deasserted, before communication
> > with the device is attempted.
> >
> > The Linux implementation is looking for these in the "reset-gpios" and
> > "post-reset-deassert-delay-ms" properties already, so use these property
> > names.
>
> > + post-reset-deassert-delay-ms:
> > + description: Time required by the device after reset has been deasserted,
> > + before it is ready for communication.
> > +
> > + reset-gpios: true
>
> Hmm, for the third time, it seems you ignored my comment that you need
> to remove the comment about these properties from the driver as part of
> this series.
>
> /*
> * Note this is a kernel internal device-property set by x86 platform code,
> * this MUST not be used in devicetree files without first adding it to
> * the DT bindings.
> */
> if (!device_property_read_u32(dev, "post-reset-deassert-delay-ms", &val))
> ihid_of->post_reset_delay_ms = val;

DT devices should have a specific compatible that gives enough detail to
handle this delay or *any* other power sequencing requirement.

OTOH, we've already got one other delay property, what's one more. Sigh.

Acked-by: Rob Herring <robh@xxxxxxxxxx>

Rob