USB: xHCI: Add stack support for xHCI

This adds stack layer for eXtensible Host Controller Interface
which facilitates use of USB 3.0 in host mode.

Adapting xHCI host controller driver in linux-kernel
by Sarah Sharp to needs in u-boot.

Initial porting from Linux kernel version 3.4, with following
top commit history of drivers/usb/host/xhci* :
cf84055 xHCI: Cleanup isoc transfer ring when TD length mismatch found

This adds the basic xHCI host controller driver with bare minimum
features:
- Control/Bulk transfer support has been added with required
  infrastructure for necessary xHC data structures.
- Stream protocol hasn't been supported yet.
- No support for quirky devices has been added.

Signed-off-by: Vikas C Sajjan <vikas.sajjan@samsung.com>
Signed-off-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Marek Vasut <marex@denx.de>

1 files changed, 31 insertions, 2 deletions

diff --git a/common/usb.c b/common/usb.c
index c97f522bed..e23d788855 100644
--- a/common/usb.c
+++ b/common/usb.c
@@ -855,6 +855,16 @@ void usb_free_device(void)
 }
 
 /*
+ * XHCI issues Enable Slot command and thereafter
+ * allocates device contexts. Provide a weak alias
+ * function for the purpose, so that XHCI overrides it
+ * and EHCI/OHCI just work out of the box.
+ */
+__weak int usb_alloc_device(struct usb_device *udev)
+{
+	return 0;
+}
+/*
  * By the time we get here, the device has gotten a new device ID
  * and is in the default state. We need to identify the thing and
  * get the ball rolling..
@@ -867,6 +877,17 @@ int usb_new_device(struct usb_device *dev)
 	int tmp;
 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
 
+	/*
+	 * Allocate usb 3.0 device context.
+	 * USB 3.0 (xHCI) protocol tries to allocate device slot
+	 * and related data structures first. This call does that.
+	 * Refer to sec 4.3.2 in xHCI spec rev1.0
+	 */
+	if (usb_alloc_device(dev)) {
+		printf("Cannot allocate device context to get SLOT_ID\n");
+		return -1;
+	}
+
 	/* We still haven't set the Address yet */
 	addr = dev->devnum;
 	dev->devnum = 0;
@@ -897,7 +918,7 @@ int usb_new_device(struct usb_device *dev)
 	 * http://sourceforge.net/mailarchive/forum.php?
 	 * thread_id=5729457&forum_id=5398
 	 */
-	struct usb_device_descriptor *desc;
+	__maybe_unused struct usb_device_descriptor *desc;
 	int port = -1;
 	struct usb_device *parent = dev->parent;
 	unsigned short portstatus;
@@ -914,6 +935,13 @@ int usb_new_device(struct usb_device *dev)
 	dev->epmaxpacketin[0] = 64;
 	dev->epmaxpacketout[0] = 64;
 
+	/*
+	 * XHCI needs to issue a Address device command to setup
+	 * proper device context structures, before it can interact
+	 * with the device. So a get_descriptor will fail before any
+	 * of that is done for XHCI unlike EHCI.
+	 */
+#ifndef CONFIG_USB_XHCI
 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, 64);
 	if (err < 0) {
 		debug("usb_new_device: usb_get_descriptor() failed\n");
@@ -926,11 +954,12 @@ int usb_new_device(struct usb_device *dev)
 	 * to differentiate between HUB and DEVICE.
 	 */
 	dev->descriptor.bDeviceClass = desc->bDeviceClass;
+#endif
 
-	/* find the port number we're at */
 	if (parent) {
 		int j;
 
+		/* find the port number we're at */
 		for (j = 0; j < parent->maxchild; j++) {
 			if (parent->children[j] == dev) {
 				port = j;