This attribute file, named "usb_capability", will show the
supported USB modes, which are USB 2.0, USB 3.2 and USB4.
These modes are defined in the USB Type-C (R2.0) and USB
Power Delivery (R3.0 V2.0) Specifications.
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Tested-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> # SM8450-HDK
Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-class-typec | 13 ++++
drivers/usb/typec/class.c | 81 +++++++++++++++++++++
drivers/usb/typec/class.h | 1 +
include/linux/usb/typec.h | 17 +++++
4 files changed, 112 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-class-typec b/Documentation/ABI/testing/sysfs-class-typec
index 281b995beb05..7c307f02d99e 100644
--- a/Documentation/ABI/testing/sysfs-class-typec
+++ b/Documentation/ABI/testing/sysfs-class-typec
@@ -149,6 +149,19 @@ Description:
advertise to the partner. The currently used capabilities are in
brackets. Selection happens by writing to the file.
+What: /sys/class/typec/<port>/usb_capability
+Date: May 2024
+Contact: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
+Description: Lists the supported USB Modes. The default USB mode that is used
+ next time with the Enter_USB Message is in brackets. The default
+ mode can be changed by writing to the file when supported by the
+ driver.
+
+ Valid values:
+ - usb2 (USB 2.0)
+ - usb3 (USB 3.2)
+ - usb4 (USB4)
+
USB Type-C partner devices (eg. /sys/class/typec/port0-partner/)
What: /sys/class/typec/<port>-partner/accessory_mode
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 9262fcd4144f..9c26d2ad40df 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -219,6 +219,13 @@ static ssize_t usb_power_delivery_revision_show(struct device *dev,
char *buf);
static DEVICE_ATTR_RO(usb_power_delivery_revision);
+static const char * const usb_modes[] = {
+ [USB_MODE_NONE] = "none",
+ [USB_MODE_USB2] = "usb2",
+ [USB_MODE_USB3] = "usb3",
+ [USB_MODE_USB4] = "usb4"
+};
+
/* ------------------------------------------------------------------------- */
/* Alternate Modes */
@@ -1289,6 +1296,67 @@ EXPORT_SYMBOL_GPL(typec_unregister_cable);
/* ------------------------------------------------------------------------- */
/* USB Type-C ports */
+/**
+ * typec_port_set_usb_mode - Set the operational USB mode for the port
+ * @port: USB Type-C port
+ * @mode: USB Mode (USB2, USB3 or USB4)
+ *
+ * @mode will be used with the next Enter_USB message. Existing connections are
+ * not affected.
+ */
+void typec_port_set_usb_mode(struct typec_port *port, enum usb_mode mode)
+{
+ port->usb_mode = mode;
+}
+EXPORT_SYMBOL_GPL(typec_port_set_usb_mode);
+
+static ssize_t
+usb_capability_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ enum usb_mode mode = to_typec_port(dev)->usb_mode;
+ u8 cap = to_typec_port(dev)->cap->usb_capability;
+ int len = 0;
+ int i;
+
+ for (i = USB_MODE_USB2; i < USB_MODE_USB4 + 1; i++) {
+ if (!(BIT(i - 1) & cap))
+ continue;
+
+ if (i == mode)
+ len += sysfs_emit_at(buf, len, "[%s] ", usb_modes[i]);
+ else
+ len += sysfs_emit_at(buf, len, "%s ", usb_modes[i]);
+ }
+
+ buf[len - 1] = '\n';
+ return len;
+}
+
+static ssize_t
+usb_capability_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct typec_port *port = to_typec_port(dev);
+ int ret = 0;
+ int mode;
+
+ if (!port->ops || !port->ops->usb_mode_set)
+ return -EOPNOTSUPP;
+
+ mode = sysfs_match_string(usb_modes, buf);
+ if (mode < 0)
+ return mode;
+
+ ret = port->ops->usb_mode_set(port, mode);
+ if (ret)
+ return ret;
+
+ port->usb_mode = mode;
+
+ return size;
+}
+static DEVICE_ATTR_RW(usb_capability);
+
/**
* typec_port_set_usb_power_delivery - Assign USB PD for port.
* @port: USB Type-C port.
@@ -1757,6 +1825,7 @@ static struct attribute *typec_attrs[] = {
&dev_attr_vconn_source.attr,
&dev_attr_port_type.attr,
&dev_attr_orientation.attr,
+ &dev_attr_usb_capability.attr,
NULL,
};
@@ -1790,6 +1859,11 @@ static umode_t typec_attr_is_visible(struct kobject *kobj,
if (port->cap->orientation_aware)
return 0444;
return 0;
+ } else if (attr == &dev_attr_usb_capability.attr) {
+ if (!port->cap->usb_capability)
+ return 0;
+ if (!port->ops || !port->ops->usb_mode_set)
+ return 0444;
}
return attr->mode;
@@ -2428,6 +2502,13 @@ struct typec_port *typec_register_port(struct device *parent,
port->con.attach = typec_partner_attach;
port->con.deattach = typec_partner_deattach;
+ if (cap->usb_capability & USB_CAPABILITY_USB4)
+ port->usb_mode = USB_MODE_USB4;
+ else if (cap->usb_capability & USB_CAPABILITY_USB3)
+ port->usb_mode = USB_MODE_USB3;
+ else if (cap->usb_capability & USB_CAPABILITY_USB2)
+ port->usb_mode = USB_MODE_USB2;
+
device_initialize(&port->dev);
port->dev.class = &typec_class;
port->dev.parent = parent;
diff --git a/drivers/usb/typec/class.h b/drivers/usb/typec/class.h
index 7485cdb9dd20..85bc50aa54f7 100644
--- a/drivers/usb/typec/class.h
+++ b/drivers/usb/typec/class.h
@@ -55,6 +55,7 @@ struct typec_port {
enum typec_role vconn_role;
enum typec_pwr_opmode pwr_opmode;
enum typec_port_type port_type;
+ enum usb_mode usb_mode;
struct mutex port_type_lock;
enum typec_orientation orientation;
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index 549275f8ac1b..d8999472212d 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -87,6 +87,17 @@ enum typec_orientation {
TYPEC_ORIENTATION_REVERSE,
};
+enum usb_mode {
+ USB_MODE_NONE,
+ USB_MODE_USB2,
+ USB_MODE_USB3,
+ USB_MODE_USB4
+};
+
+#define USB_CAPABILITY_USB2 BIT(0)
+#define USB_CAPABILITY_USB3 BIT(1)
+#define USB_CAPABILITY_USB4 BIT(2)
+
/*
* struct enter_usb_data - Enter_USB Message details
* @eudo: Enter_USB Data Object
@@ -240,6 +251,7 @@ struct typec_partner_desc {
* @port_type_set: Set port type
* @pd_get: Get available USB Power Delivery Capabilities.
* @pd_set: Set USB Power Delivery Capabilities.
+ * @usb_mode_set: Set the USB Mode to be used with Enter_USB message
*/
struct typec_operations {
int (*try_role)(struct typec_port *port, int role);
@@ -250,6 +262,7 @@ struct typec_operations {
enum typec_port_type type);
struct usb_power_delivery **(*pd_get)(struct typec_port *port);
int (*pd_set)(struct typec_port *port, struct usb_power_delivery *pd);
+ int (*usb_mode_set)(struct typec_port *port, enum usb_mode mode);
};
enum usb_pd_svdm_ver {
@@ -267,6 +280,7 @@ enum usb_pd_svdm_ver {
* @svdm_version: USB PD Structured VDM version if supported
* @prefer_role: Initial role preference (DRP ports).
* @accessory: Supported Accessory Modes
+ * @usb_capability: Supported USB Modes
* @fwnode: Optional fwnode of the port
* @driver_data: Private pointer for driver specific info
* @pd: Optional USB Power Delivery Support
@@ -283,6 +297,7 @@ struct typec_capability {
int prefer_role;
enum typec_accessory accessory[TYPEC_MAX_ACCESSORY];
unsigned int orientation_aware:1;
+ u8 usb_capability;
struct fwnode_handle *fwnode;
void *driver_data;
@@ -350,6 +365,8 @@ int typec_port_set_usb_power_delivery(struct typec_port *port, struct usb_power_
int typec_partner_set_usb_power_delivery(struct typec_partner *partner,
struct usb_power_delivery *pd);
+void typec_port_set_usb_mode(struct typec_port *port, enum usb_mode mode);
+
/**
* struct typec_connector - Representation of Type-C port for external drivers
* @attach: notification about device removal
--
2.45.2
