[PATCH v4 4/4] usb: typec: ucsi: Register SOP' alternate modes with cable plug

[Jameson Thies <jthies@google.com>]

Register SOP' alternate modes with a Type-C Connector Class cable plug.
Alternate modes are queried from the PPM using the GET_ALTERNATE_MODES
command with recipient set to SOP'.

Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Jameson Thies <jthies@google.com>
---
SOP' GET_ALTERNATE_MODE responses from the PPM are correctly registered
to the cable plug.
nospike-rev4 /sys/class/typec # ls port0-cable/port0-plug0/
device  port0-plug0.0  port0-plug0.1  power  subsystem  uevent

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 | 60 +++++++++++++++++++++++++++++++++++
 drivers/usb/typec/ucsi/ucsi.h |  2 ++
 2 files changed, 62 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 3b64a0f51041c..cf52cb34d2859 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -399,6 +399,27 @@ static int ucsi_register_altmode(struct ucsi_connector *con,
 
 		con->partner_altmode[i] = alt;
 		break;
+	case UCSI_RECIPIENT_SOP_P:
+		i = ucsi_next_altmode(con->plug_altmode);
+		if (i < 0) {
+			ret = i;
+			goto err;
+		}
+
+		ret = ucsi_altmode_next_mode(con->plug_altmode, desc->svid);
+		if (ret < 0)
+			return ret;
+
+		desc->mode = ret;
+
+		alt = typec_plug_register_altmode(con->plug, desc);
+		if (IS_ERR(alt)) {
+			ret = PTR_ERR(alt);
+			goto err;
+		}
+
+		con->plug_altmode[i] = alt;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -566,6 +587,9 @@ static void ucsi_unregister_altmodes(struct ucsi_connector *con, u8 recipient)
 	case UCSI_RECIPIENT_SOP:
 		adev = con->partner_altmode;
 		break;
+	case UCSI_RECIPIENT_SOP_P:
+		adev = con->plug_altmode;
+		break;
 	default:
 		return;
 	}
@@ -836,6 +860,33 @@ static void ucsi_unregister_partner_pdos(struct ucsi_connector *con)
 	con->partner_pd = NULL;
 }
 
+static int ucsi_register_plug(struct ucsi_connector *con)
+{
+	struct typec_plug *plug;
+	struct typec_plug_desc desc = {.index = TYPEC_PLUG_SOP_P};
+
+	plug = typec_register_plug(con->cable, &desc);
+	if (IS_ERR(plug)) {
+		dev_err(con->ucsi->dev,
+			"con%d: failed to register plug (%ld)\n", con->num,
+			PTR_ERR(plug));
+		return PTR_ERR(plug);
+	}
+
+	con->plug = plug;
+	return 0;
+}
+
+static void ucsi_unregister_plug(struct ucsi_connector *con)
+{
+	if (!con->plug)
+		return;
+
+	ucsi_unregister_altmodes(con, UCSI_RECIPIENT_SOP_P);
+	typec_unregister_plug(con->plug);
+	con->plug = NULL;
+}
+
 static int ucsi_register_cable(struct ucsi_connector *con)
 {
 	struct typec_cable *cable;
@@ -879,6 +930,7 @@ static void ucsi_unregister_cable(struct ucsi_connector *con)
 	if (!con->cable)
 		return;
 
+	ucsi_unregister_plug(con);
 	typec_unregister_cable(con->cable);
 	memset(&con->cable_identity, 0, sizeof(con->cable_identity));
 	con->cable = NULL;
@@ -1085,6 +1137,14 @@ static int ucsi_check_cable(struct ucsi_connector *con)
 	if (ret < 0)
 		return ret;
 
+	ret = ucsi_register_plug(con);
+	if (ret < 0)
+		return ret;
+
+	ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP_P);
+	if (ret < 0)
+		return ret;
+
 	return 0;
 }
 
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index b89fae82e8ce7..32daf5f586505 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -429,9 +429,11 @@ struct ucsi_connector {
 	struct typec_port *port;
 	struct typec_partner *partner;
 	struct typec_cable *cable;
+	struct typec_plug *plug;
 
 	struct typec_altmode *port_altmode[UCSI_MAX_ALTMODES];
 	struct typec_altmode *partner_altmode[UCSI_MAX_ALTMODES];
+	struct typec_altmode *plug_altmode[UCSI_MAX_ALTMODES];
 
 	struct typec_capability typec_cap;
 
-- 
2.44.0.rc1.240.g4c46232300-goog