Some functions support speeds other than SuperSpeed. Add max_speed
attribute to configfs gadget allowing user to specify the maximum speed
the composite driver supports. The valid input speed names are
super-speed-plus, super-speed, high-speed, full-speed, and low-speed.
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
---
Documentation/ABI/testing/configfs-usb-gadget | 4 +++
drivers/usb/gadget/configfs.c | 43 +++++++++++++++++++++++++++
2 files changed, 47 insertions(+)
diff --git a/Documentation/ABI/testing/configfs-usb-gadget b/Documentation/ABI/testing/configfs-usb-gadget
index 95a36589a66b..4594cc2435e8 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget
+++ b/Documentation/ABI/testing/configfs-usb-gadget
@@ -16,6 +16,10 @@ Description:
write UDC's name found in /sys/class/udc/*
to bind a gadget, empty string "" to unbind.
+ max_speed - maximum speed the driver supports. Valid
+ names are super-speed-plus, super-speed,
+ high-speed, full-speed, and low-speed.
+
bDeviceClass - USB device class code
bDeviceSubClass - USB device subclass code
bDeviceProtocol - USB device protocol code
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index ab9ac48a751a..32b637e3e1fa 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -293,6 +293,47 @@ static ssize_t gadget_dev_desc_UDC_store(struct config_item *item,
return ret;
}
+static ssize_t gadget_dev_desc_max_speed_show(struct config_item *item,
+ char *page)
+{
+ enum usb_device_speed speed = to_gadget_info(item)->composite.max_speed;
+
+ return sprintf(page, "%s\n", usb_speed_string(speed));
+}
+
+static ssize_t gadget_dev_desc_max_speed_store(struct config_item *item,
+ const char *page, size_t len)
+{
+ struct gadget_info *gi = to_gadget_info(item);
+
+ mutex_lock(&gi->lock);
+
+ /* Prevent changing of max_speed after the driver is binded */
+ if (gi->composite.gadget_driver.udc_name)
+ goto err;
+
+ if (strncmp(page, "super-speed-plus", 16) == 0)
+ gi->composite.max_speed = USB_SPEED_SUPER_PLUS;
+ else if (strncmp(page, "super-speed", 11) == 0)
+ gi->composite.max_speed = USB_SPEED_SUPER;
+ else if (strncmp(page, "high-speed", 10) == 0)
+ gi->composite.max_speed = USB_SPEED_HIGH;
+ else if (strncmp(page, "full-speed", 10) == 0)
+ gi->composite.max_speed = USB_SPEED_FULL;
+ else if (strncmp(page, "low-speed", 9) == 0)
+ gi->composite.max_speed = USB_SPEED_LOW;
+ else
+ goto err;
+
+ gi->composite.gadget_driver.max_speed = gi->composite.max_speed;
+
+ mutex_unlock(&gi->lock);
+ return len;
+err:
+ mutex_unlock(&gi->lock);
+ return -EINVAL;
+}
+
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
@@ -302,6 +343,7 @@ CONFIGFS_ATTR(gadget_dev_desc_, idProduct);
CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
CONFIGFS_ATTR(gadget_dev_desc_, UDC);
+CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
static struct configfs_attribute *gadget_root_attrs[] = {
&gadget_dev_desc_attr_bDeviceClass,
@@ -313,6 +355,7 @@ static struct configfs_attribute *gadget_root_attrs[] = {
&gadget_dev_desc_attr_bcdDevice,
&gadget_dev_desc_attr_bcdUSB,
&gadget_dev_desc_attr_UDC,
+ &gadget_dev_desc_attr_max_speed,
NULL,
};
--
2.11.0
