Re: [PATCH 2/6] usb: typec: Provide PD Specification Revision for cable and partner
On Thu, Jan 28, 2021 at 10:14:02PM -0800, Benson Leung wrote:
> The USB Power Delivery specification Section 6.2.1.1.5 outlines
> revision backward compatibility requirements starting from Revision 3.0.
>
> The Port, the Cable Plug, and the Port Partner may support either
> revision 2 or revision 3 independently, and communication between ports,
> partners, and cables of different revisions are allowed under rules
> that the parties agree to communicate between each other using the
> lowest common operating revision.
>
> This may mean that Port-to-Partner operating revision comms may be
> different than Port-to-CablePlug operating revision comms. For example,
> it is possible for a R3.0 port to communicate with a R3.0 partner
> using R3.0 messages, while the R3.0 port (in the same session) must
> communicate with the R2.0 cable using R2.0 messages only.
>
> Introduce individual revision number properties for cable
> and port partner so that the port can track them independently.
>
> Signed-off-by: Benson Leung
Reviewed-by: Heikki Krogerus
> ---
> Documentation/ABI/testing/sysfs-class-typec | 13 +
> drivers/usb/typec/class.c | 30 ++---
> include/linux/usb/typec.h | 10 +++
> 3 files changed, 49 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-class-typec
> b/Documentation/ABI/testing/sysfs-class-typec
> index b61480535fdc..40122d915ae1 100644
> --- a/Documentation/ABI/testing/sysfs-class-typec
> +++ b/Documentation/ABI/testing/sysfs-class-typec
> @@ -112,6 +112,19 @@ Description:
> - "3.0": USB Power Delivery Release 3.0
> - "3.1": USB Power Delivery Release 3.1
>
> +What:
> /sys/class/typec/-{partner|cable}/usb_power_delivery_revision
> +Date:January 2021
> +Contact: Benson Leung
> +Description:
> + Revision number of the supported USB Power Delivery
> + specification of the port partner or cable, 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//usb_typec_revision
> Date:April 2017
> Contact: Heikki Krogerus
> diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
> index 4f60ee7ba76a..b5241f4756c2 100644
> --- a/drivers/usb/typec/class.c
> +++ b/drivers/usb/typec/class.c
> @@ -27,6 +27,7 @@ struct typec_cable {
> enum typec_plug_typetype;
> struct usb_pd_identity *identity;
> unsigned intactive:1;
> + u16 pd_revision; /* 0300H = "3.0" */
> };
>
> struct typec_partner {
> @@ -36,6 +37,7 @@ struct typec_partner {
> enum typec_accessoryaccessory;
> struct ida mode_ids;
> int num_altmodes;
> + u16 pd_revision; /* 0300H = "3.0" */
> };
>
> struct typec_port {
> @@ -264,6 +266,11 @@ type_show(struct device *dev, struct device_attribute
> *attr, char *buf)
> }
> static DEVICE_ATTR_RO(type);
>
> +static ssize_t usb_power_delivery_revision_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf);
> +static DEVICE_ATTR_RO(usb_power_delivery_revision);
> +
> /* -
> */
> /* Alternate Modes */
>
> @@ -680,6 +687,7 @@ static struct attribute *typec_partner_attrs[] = {
> _attr_supports_usb_power_delivery.attr,
> _attr_number_of_alternate_modes.attr,
> _attr_type.attr,
> + _attr_usb_power_delivery_revision.attr,
> NULL
> };
>
> @@ -815,6 +823,7 @@ struct typec_partner *typec_register_partner(struct
> typec_port *port,
> partner->usb_pd = desc->usb_pd;
> partner->accessory = desc->accessory;
> partner->num_altmodes = -1;
> + partner->pd_revision = desc->pd_revision;
>
> if (desc->identity) {
> /*
> @@ -1028,6 +1037,7 @@ static DEVICE_ATTR_RO(plug_type);
> static struct attribute *typec_cable_attrs[] = {
> _attr_type.attr,
> _attr_plug_type.attr,
> + _attr_usb_power_delivery_revision.attr,
> NULL
> };
> ATTRIBUTE_GROUPS(typec_cable);
> @@ -1130,6 +1140,7 @@ struct typec_cable *typec_register_cable(struct
> typec_port *port,
>
> cable->type = desc->type;
> cable->active = desc->active;
> + cable->pd_revision = desc->pd_revision;
>
> if (desc->identity) {
> /*
> @@ -1499,12 +1510,23 @@ static ssize_t
> usb_power_delivery_revision_show(struct device *dev,
>
[PATCH 2/6] usb: typec: Provide PD Specification Revision for cable and partner
The USB Power Delivery specification Section 6.2.1.1.5 outlines
revision backward compatibility requirements starting from Revision 3.0.
The Port, the Cable Plug, and the Port Partner may support either
revision 2 or revision 3 independently, and communication between ports,
partners, and cables of different revisions are allowed under rules
that the parties agree to communicate between each other using the
lowest common operating revision.
This may mean that Port-to-Partner operating revision comms may be
different than Port-to-CablePlug operating revision comms. For example,
it is possible for a R3.0 port to communicate with a R3.0 partner
using R3.0 messages, while the R3.0 port (in the same session) must
communicate with the R2.0 cable using R2.0 messages only.
Introduce individual revision number properties for cable
and port partner so that the port can track them independently.
Signed-off-by: Benson Leung
---
Documentation/ABI/testing/sysfs-class-typec | 13 +
drivers/usb/typec/class.c | 30 ++---
include/linux/usb/typec.h | 10 +++
3 files changed, 49 insertions(+), 4 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-typec
b/Documentation/ABI/testing/sysfs-class-typec
index b61480535fdc..40122d915ae1 100644
--- a/Documentation/ABI/testing/sysfs-class-typec
+++ b/Documentation/ABI/testing/sysfs-class-typec
@@ -112,6 +112,19 @@ Description:
- "3.0": USB Power Delivery Release 3.0
- "3.1": USB Power Delivery Release 3.1
+What:
/sys/class/typec/-{partner|cable}/usb_power_delivery_revision
+Date: January 2021
+Contact: Benson Leung
+Description:
+ Revision number of the supported USB Power Delivery
+ specification of the port partner or cable, 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//usb_typec_revision
Date: April 2017
Contact: Heikki Krogerus
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 4f60ee7ba76a..b5241f4756c2 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -27,6 +27,7 @@ struct typec_cable {
enum typec_plug_typetype;
struct usb_pd_identity *identity;
unsigned intactive:1;
+ u16 pd_revision; /* 0300H = "3.0" */
};
struct typec_partner {
@@ -36,6 +37,7 @@ struct typec_partner {
enum typec_accessoryaccessory;
struct ida mode_ids;
int num_altmodes;
+ u16 pd_revision; /* 0300H = "3.0" */
};
struct typec_port {
@@ -264,6 +266,11 @@ type_show(struct device *dev, struct device_attribute
*attr, char *buf)
}
static DEVICE_ATTR_RO(type);
+static ssize_t usb_power_delivery_revision_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf);
+static DEVICE_ATTR_RO(usb_power_delivery_revision);
+
/* - */
/* Alternate Modes */
@@ -680,6 +687,7 @@ static struct attribute *typec_partner_attrs[] = {
_attr_supports_usb_power_delivery.attr,
_attr_number_of_alternate_modes.attr,
_attr_type.attr,
+ _attr_usb_power_delivery_revision.attr,
NULL
};
@@ -815,6 +823,7 @@ struct typec_partner *typec_register_partner(struct
typec_port *port,
partner->usb_pd = desc->usb_pd;
partner->accessory = desc->accessory;
partner->num_altmodes = -1;
+ partner->pd_revision = desc->pd_revision;
if (desc->identity) {
/*
@@ -1028,6 +1037,7 @@ static DEVICE_ATTR_RO(plug_type);
static struct attribute *typec_cable_attrs[] = {
_attr_type.attr,
_attr_plug_type.attr,
+ _attr_usb_power_delivery_revision.attr,
NULL
};
ATTRIBUTE_GROUPS(typec_cable);
@@ -1130,6 +1140,7 @@ struct typec_cable *typec_register_cable(struct
typec_port *port,
cable->type = desc->type;
cable->active = desc->active;
+ cable->pd_revision = desc->pd_revision;
if (desc->identity) {
/*
@@ -1499,12 +1510,23 @@ static ssize_t usb_power_delivery_revision_show(struct
device *dev,
struct device_attribute *attr,
char *buf)
{
- struct typec_port *p = to_typec_port(dev);
- u16 rev = p->cap->pd_revision;
+ u16 rev = 0;
- return sprintf(buf, "%d.%d\n", (rev >> 8) & 0xff, (rev >> 4) &
