usb: typec: Expose Product Type VDOs via sysfs

A PD-capable device can return up to 3 Product Type VDOs as part of its
DiscoverIdentity Response (USB PD Spec, Rev 3.0, Version 2.0, Section
6.4.4.3.1). Add sysfs attributes to expose these to userspace.

Cc: Benson Leung <bleung@chromium.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Link: https://lore.kernel.org/r/20201125084911.1077462-2-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/ABI/testing/sysfs-class-typec

@@ -228,6 +228,30 @@ Description:
 		will show 0 until Discover Identity command result becomes
 		available. The value can be polled.
 
+What:		/sys/class/typec/<port>-{partner|cable}/identity/product_type_vdo1
+Date:		October 2020
+Contact:	Prashant Malani <pmalani@chromium.org>
+Description:
+		1st Product Type VDO of Discover Identity command result.
+		The value will show 0 until Discover Identity command result becomes
+		available and a valid Product Type VDO is returned.
+
+What:		/sys/class/typec/<port>-{partner|cable}/identity/product_type_vdo2
+Date:		October 2020
+Contact:	Prashant Malani <pmalani@chromium.org>
+Description:
+		2nd Product Type VDO of Discover Identity command result.
+		The value will show 0 until Discover Identity command result becomes
+		available and a valid Product Type VDO is returned.
+
+What:		/sys/class/typec/<port>-{partner|cable}/identity/product_type_vdo3
+Date:		October 2020
+Contact:	Prashant Malani <pmalani@chromium.org>
+Description:
+		3rd Product Type VDO of Discover Identity command result.
+		The value will show 0 until Discover Identity command result becomes
+		available and a valid Product Type VDO is returned.
+
 
 USB Type-C port alternate mode devices.
 

drivers/usb/typec/class.c

@@ -124,10 +124,40 @@ static ssize_t product_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(product);
 
+static ssize_t product_type_vdo1_show(struct device *dev, struct device_attribute *attr,
+				      char *buf)
+{
+	struct usb_pd_identity *id = get_pd_identity(dev);
+
+	return sysfs_emit(buf, "0x%08x\n", id->vdo[0]);
+}
+static DEVICE_ATTR_RO(product_type_vdo1);
+
+static ssize_t product_type_vdo2_show(struct device *dev, struct device_attribute *attr,
+				      char *buf)
+{
+	struct usb_pd_identity *id = get_pd_identity(dev);
+
+	return sysfs_emit(buf, "0x%08x\n", id->vdo[1]);
+}
+static DEVICE_ATTR_RO(product_type_vdo2);
+
+static ssize_t product_type_vdo3_show(struct device *dev, struct device_attribute *attr,
+				      char *buf)
+{
+	struct usb_pd_identity *id = get_pd_identity(dev);
+
+	return sysfs_emit(buf, "0x%08x\n", id->vdo[2]);
+}
+static DEVICE_ATTR_RO(product_type_vdo3);
+
 static struct attribute *usb_pd_id_attrs[] = {
 	&dev_attr_id_header.attr,
 	&dev_attr_cert_stat.attr,
 	&dev_attr_product.attr,
+	&dev_attr_product_type_vdo1.attr,
+	&dev_attr_product_type_vdo2.attr,
+	&dev_attr_product_type_vdo3.attr,
 	NULL
 };
 
@@ -146,6 +176,9 @@ static void typec_report_identity(struct device *dev)
 	sysfs_notify(&dev->kobj, "identity", "id_header");
 	sysfs_notify(&dev->kobj, "identity", "cert_stat");
 	sysfs_notify(&dev->kobj, "identity", "product");
+	sysfs_notify(&dev->kobj, "identity", "product_type_vdo1");
+	sysfs_notify(&dev->kobj, "identity", "product_type_vdo2");
+	sysfs_notify(&dev->kobj, "identity", "product_type_vdo3");
 }
 
 /* ------------------------------------------------------------------------- */