usb: gadget: add USB3 support to the printer driver

Add SS descriptors to support the capabilities provided by USB3 controller
drivers; unit tests run using a PLX 3380 [max transfer speed measured of 1Gbps]

This driver shall fallback to lower operating modes when the higher ones are
not available.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 59 insertions, 6 deletions

diff --git a/drivers/usb/gadget/legacy/printer.c b/drivers/usb/gadget/legacy/printer.c
index 6474081dcbaf..e0cf1b0d471d 100644
--- a/drivers/usb/gadget/legacy/printer.c
+++ b/drivers/usb/gadget/legacy/printer.c
@@ -208,6 +208,43 @@ static struct usb_descriptor_header *hs_printer_function[] = {
         NULL
 };
 
+/*
+ * Added endpoint descriptors for 3.0 devices
+ */
+
+static struct usb_endpoint_descriptor ss_ep_in_desc = {
+        .bLength =              USB_DT_ENDPOINT_SIZE,
+        .bDescriptorType =      USB_DT_ENDPOINT,
+        .bmAttributes =         USB_ENDPOINT_XFER_BULK,
+        .wMaxPacketSize =       cpu_to_le16(1024),
+};
+
+struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
+        .bLength =              sizeof(ss_ep_in_comp_desc),
+        .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
+};
+
+static struct usb_endpoint_descriptor ss_ep_out_desc = {
+        .bLength =              USB_DT_ENDPOINT_SIZE,
+        .bDescriptorType =      USB_DT_ENDPOINT,
+        .bmAttributes =         USB_ENDPOINT_XFER_BULK,
+        .wMaxPacketSize =       cpu_to_le16(1024),
+};
+
+struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
+        .bLength =              sizeof(ss_ep_out_comp_desc),
+        .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
+};
+
+static struct usb_descriptor_header *ss_printer_function[] = {
+        (struct usb_descriptor_header *) &intf_desc,
+        (struct usb_descriptor_header *) &ss_ep_in_desc,
+        (struct usb_descriptor_header *) &ss_ep_in_comp_desc,
+        (struct usb_descriptor_header *) &ss_ep_out_desc,
+        (struct usb_descriptor_header *) &ss_ep_out_comp_desc,
+        NULL
+};
+
 static struct usb_otg_descriptor otg_descriptor = {
         .bLength =              sizeof otg_descriptor,
         .bDescriptorType =      USB_DT_OTG,
@@ -220,7 +257,20 @@ static const struct usb_descriptor_header *otg_desc[] = {
 };
 
 /* maxpacket and other transfer characteristics vary by speed. */
-#define ep_desc(g, hs, fs) (((g)->speed == USB_SPEED_HIGH)?(hs):(fs))
+static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
+                                        struct usb_endpoint_descriptor *fs,
+                                        struct usb_endpoint_descriptor *hs,
+                                        struct usb_endpoint_descriptor *ss)
+{
+        switch (gadget->speed) {
+        case USB_SPEED_SUPER:
+                return ss;
+        case USB_SPEED_HIGH:
+                return hs;
+        default:
+                return fs;
+        }
+}
 
 /*-------------------------------------------------------------------------*/
 
@@ -793,11 +843,12 @@ set_printer_interface(struct printer_dev *dev)
 {
         int                     result = 0;
 
-        dev->in_ep->desc = ep_desc(dev->gadget, &hs_ep_in_desc, &fs_ep_in_desc);
+        dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
+                                &ss_ep_in_desc);
         dev->in_ep->driver_data = dev;
 
-        dev->out_ep->desc = ep_desc(dev->gadget, &hs_ep_out_desc,
-                                    &fs_ep_out_desc);
+        dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
+                                    &hs_ep_out_desc, &ss_ep_out_desc);
         dev->out_ep->driver_data = dev;
 
         result = usb_ep_enable(dev->in_ep);
@@ -1016,9 +1067,11 @@ autoconf_fail:
         /* assumes that all endpoints are dual-speed */
         hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
         hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
+        ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
+        ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
 
         ret = usb_assign_descriptors(f, fs_printer_function,
-                        hs_printer_function, NULL);
+                        hs_printer_function, ss_printer_function);
         if (ret)
                 return ret;
 
@@ -1253,7 +1306,7 @@ static __refdata struct usb_composite_driver printer_driver = {
         .name           = shortname,
         .dev            = &device_desc,
         .strings        = dev_strings,
-        .max_speed      = USB_SPEED_HIGH,
+        .max_speed      = USB_SPEED_SUPER,
         .bind           = printer_bind,
         .unbind         = printer_unbind,
 };