Re: [PATCH 1/6] usb: typec: Standardize PD Revision format with Type-C Revision

From: Heikki Krogerus
Date: Mon Feb 01 2021 - 07:41:06 EST


On Thu, Jan 28, 2021 at 10:14:01PM -0800, Benson Leung wrote:
> The Type-C Revision was in a specific BCD format "0120H" for 1.2.
> USB PD revision numbers follow a similar pattern with "0300H" for 3.0.
>
> Standardizes the sysfs format for usb_power_delivery_revision
> to align with the BCD format used for usb_typec_revision.
>
> Example values:
> - "2.0": USB Power Delivery Release 2.0
> - "3.0": USB Power Delivery Release 3.0
> - "3.1": USB Power Delivery Release 3.1
>
> Signed-off-by: Benson Leung <bleung@xxxxxxxxxxxx>

I guess it's OK to modify the ABI like this.

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> Documentation/ABI/testing/sysfs-class-typec | 7 ++++++-
> drivers/usb/typec/class.c | 3 ++-
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-typec b/Documentation/ABI/testing/sysfs-class-typec
> index 8eab41e79ce6..b61480535fdc 100644
> --- a/Documentation/ABI/testing/sysfs-class-typec
> +++ b/Documentation/ABI/testing/sysfs-class-typec
> @@ -105,7 +105,12 @@ Date: April 2017
> Contact: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Description:
> Revision number of the supported USB Power Delivery
> - specification, or 0 when USB Power Delivery is not supported.
> + specification, or 0.0 when USB Power Delivery is not supported.
> +
> + Example values:
> + - "2.0": USB Power Delivery Release 2.0
> + - "3.0": USB Power Delivery Release 3.0
> + - "3.1": USB Power Delivery Release 3.1
>
> What: /sys/class/typec/<port>/usb_typec_revision
> Date: April 2017
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index 8f77669f9cf4..4f60ee7ba76a 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -1500,8 +1500,9 @@ static ssize_t usb_power_delivery_revision_show(struct device *dev,
> char *buf)
> {
> struct typec_port *p = to_typec_port(dev);
> + u16 rev = p->cap->pd_revision;
>
> - return sprintf(buf, "%d\n", (p->cap->pd_revision >> 8) & 0xff);
> + return sprintf(buf, "%d.%d\n", (rev >> 8) & 0xff, (rev >> 4) & 0xf);
> }
> static DEVICE_ATTR_RO(usb_power_delivery_revision);
>
> --
> 2.30.0.365.g02bc693789-goog

thanks,

--
heikki