[PATCH] usb: gadget: add USB3 support to the printer driver

From: Jorge Ramirez-Ortiz
Date: Tue Nov 18 2014 - 15:12:24 EST


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@xxxxxxxxxx>
---
drivers/usb/gadget/legacy/printer.c | 65 +++++++++++++++++++++++++++++++++----
1 file changed, 59 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/gadget/legacy/printer.c b/drivers/usb/gadget/legacy/printer.c
index 6474081..456730b 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,
};
--
1.9.1

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