[PATCH v4 2/4] usb: typec: ucsi: Register cables based on GET_CABLE_PROPERTY

From: Jameson Thies
Date: Mon Mar 04 2024 - 21:59:26 EST


Register cables with the Type-C Connector Class in the UCSI driver based
on the PPM response to GET_CABLE_PROPERTY. Registered cable properties
include plug type, cable type and major revision.

Reviewed-by: Benson Leung <bleung@xxxxxxxxxxxx>
Reviewed-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Jameson Thies <jthies@xxxxxxxxxx>
---
Expected cable properties populate the USB Type-C connector class sysfs
paths:
nospike-rev4 /sys/class/typec # ls port0-cable
device identity plug_type port0-plug0 power subsystem type uevent
usb_power_delivery_revision

Changes in v4:
- None.

Changes in v3:
- None.

Changes in v2:
- Shortened lines to within 80 characters.
- Tested on usb-testing branch merged with chromeOS 6.8-rc2 kernel.

drivers/usb/typec/ucsi/ucsi.c | 73 +++++++++++++++++++++++++++++++++++
drivers/usb/typec/ucsi/ucsi.h | 5 +++
2 files changed, 78 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index ae105383e69e7..7c84687b5d1a3 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -734,6 +734,52 @@ static void ucsi_unregister_partner_pdos(struct ucsi_connector *con)
con->partner_pd = NULL;
}

+static int ucsi_register_cable(struct ucsi_connector *con)
+{
+ struct typec_cable *cable;
+ struct typec_cable_desc desc = {};
+
+ switch (UCSI_CABLE_PROP_FLAG_PLUG_TYPE(con->cable_prop.flags)) {
+ case UCSI_CABLE_PROPERTY_PLUG_TYPE_A:
+ desc.type = USB_PLUG_TYPE_A;
+ break;
+ case UCSI_CABLE_PROPERTY_PLUG_TYPE_B:
+ desc.type = USB_PLUG_TYPE_B;
+ break;
+ case UCSI_CABLE_PROPERTY_PLUG_TYPE_C:
+ desc.type = USB_PLUG_TYPE_C;
+ break;
+ default:
+ desc.type = USB_PLUG_NONE;
+ break;
+ }
+
+ desc.active = !!(UCSI_CABLE_PROP_FLAG_ACTIVE_CABLE &
+ con->cable_prop.flags);
+ desc.pd_revision = UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV_AS_BCD(
+ con->cable_prop.flags);
+
+ cable = typec_register_cable(con->port, &desc);
+ if (IS_ERR(cable)) {
+ dev_err(con->ucsi->dev,
+ "con%d: failed to register cable (%ld)\n", con->num,
+ PTR_ERR(cable));
+ return PTR_ERR(cable);
+ }
+
+ con->cable = cable;
+ return 0;
+}
+
+static void ucsi_unregister_cable(struct ucsi_connector *con)
+{
+ if (!con->cable)
+ return;
+
+ typec_unregister_cable(con->cable);
+ con->cable = NULL;
+}
+
static void ucsi_pwr_opmode_change(struct ucsi_connector *con)
{
switch (UCSI_CONSTAT_PWR_OPMODE(con->status.flags)) {
@@ -807,6 +853,7 @@ static void ucsi_unregister_partner(struct ucsi_connector *con)
typec_partner_set_usb_power_delivery(con->partner, NULL);
ucsi_unregister_partner_pdos(con);
ucsi_unregister_altmodes(con, UCSI_RECIPIENT_SOP);
+ ucsi_unregister_cable(con);
typec_unregister_partner(con->partner);
con->partner = NULL;
}
@@ -907,6 +954,30 @@ static int ucsi_check_connection(struct ucsi_connector *con)
return 0;
}

+static int ucsi_check_cable(struct ucsi_connector *con)
+{
+ u64 command;
+ int ret;
+
+ if (con->cable)
+ return 0;
+
+ command = UCSI_GET_CABLE_PROPERTY | UCSI_CONNECTOR_NUMBER(con->num);
+ ret = ucsi_send_command(con->ucsi, command, &con->cable_prop,
+ sizeof(con->cable_prop));
+ if (ret < 0) {
+ dev_err(con->ucsi->dev, "GET_CABLE_PROPERTY failed (%d)\n",
+ ret);
+ return ret;
+ }
+
+ ret = ucsi_register_cable(con);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
static void ucsi_handle_connector_change(struct work_struct *work)
{
struct ucsi_connector *con = container_of(work, struct ucsi_connector,
@@ -948,6 +1019,7 @@ static void ucsi_handle_connector_change(struct work_struct *work)
ucsi_register_partner(con);
ucsi_partner_task(con, ucsi_check_connection, 1, HZ);
ucsi_partner_task(con, ucsi_check_connector_capability, 1, HZ);
+ ucsi_partner_task(con, ucsi_check_cable, 1, HZ);

if (UCSI_CONSTAT_PWR_OPMODE(con->status.flags) ==
UCSI_CONSTAT_PWR_OPMODE_PD)
@@ -1346,6 +1418,7 @@ static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
ucsi_register_partner(con);
ucsi_pwr_opmode_change(con);
ucsi_port_psy_changed(con);
+ ucsi_check_cable(con);
}

/* Only notify USB controller if partner supports USB data */
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index 469a2baf472e4..f0aabef0b7c64 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -265,6 +265,9 @@ struct ucsi_cable_property {
#define UCSI_CABLE_PROPERTY_PLUG_TYPE_C 2
#define UCSI_CABLE_PROPERTY_PLUG_OTHER 3
#define UCSI_CABLE_PROP_FLAG_MODE_SUPPORT BIT(5)
+#define UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV(_f_) (((_f_) & GENMASK(7, 6)) >> 6)
+#define UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV_AS_BCD(_f_) \
+ UCSI_SPEC_REVISION_TO_BCD(UCSI_CABLE_PROP_FLAG_PD_MAJOR_REV(_f_))
u8 latency;
} __packed;

@@ -400,6 +403,7 @@ struct ucsi_connector {

struct typec_port *port;
struct typec_partner *partner;
+ struct typec_cable *cable;

struct typec_altmode *port_altmode[UCSI_MAX_ALTMODES];
struct typec_altmode *partner_altmode[UCSI_MAX_ALTMODES];
@@ -408,6 +412,7 @@ struct ucsi_connector {

struct ucsi_connector_status status;
struct ucsi_connector_capability cap;
+ struct ucsi_cable_property cable_prop;
struct power_supply *psy;
struct power_supply_desc psy_desc;
u32 rdo;
--
2.44.0.rc1.240.g4c46232300-goog