[U-Boot] [PATCH 2/7] usb: ehci: Move interrupt packet length check to create_int_queue

Hans de Goede hdegoede at redhat.com
Sat Sep 20 17:01:07 CEST 2014


Preperation patch to use create_int_queue outside of ehci-hcd.c .

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
 drivers/usb/host/ehci-hcd.c | 36 +++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 20830d7..cf3e3c0 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1163,6 +1163,23 @@ create_int_queue(struct usb_device *dev, unsigned long pipe, int queuesize,
 	struct int_queue *result = NULL;
 	int i;
 
+	/*
+	 * Interrupt transfers requiring several transactions are not supported
+	 * because bInterval is ignored.
+	 *
+	 * Also, ehci_submit_async() relies on wMaxPacketSize being a power of 2
+	 * <= PKT_ALIGN if several qTDs are required, while the USB
+	 * specification does not constrain this for interrupt transfers. That
+	 * means that ehci_submit_async() would support interrupt transfers
+	 * requiring several transactions only as long as the transfer size does
+	 * not require more than a single qTD.
+	 */
+	if (elementsize > usb_maxpacket(dev, pipe)) {
+		printf("%s: xfers requiring several transactions are not supported.\n",
+		       __func__);
+		return NULL;
+	}
+
 	debug("Enter create_int_queue\n");
 	if (usb_pipetype(pipe) != PIPE_INTERRUPT) {
 		debug("non-interrupt pipe (type=%lu)", usb_pipetype(pipe));
@@ -1384,24 +1401,9 @@ submit_int_msg(struct usb_device *dev, unsigned long pipe, void *buffer,
 	debug("dev=%p, pipe=%lu, buffer=%p, length=%d, interval=%d",
 	      dev, pipe, buffer, length, interval);
 
-	/*
-	 * Interrupt transfers requiring several transactions are not supported
-	 * because bInterval is ignored.
-	 *
-	 * Also, ehci_submit_async() relies on wMaxPacketSize being a power of 2
-	 * <= PKT_ALIGN if several qTDs are required, while the USB
-	 * specification does not constrain this for interrupt transfers. That
-	 * means that ehci_submit_async() would support interrupt transfers
-	 * requiring several transactions only as long as the transfer size does
-	 * not require more than a single qTD.
-	 */
-	if (length > usb_maxpacket(dev, pipe)) {
-		printf("%s: Interrupt transfers requiring several "
-			"transactions are not supported.\n", __func__);
-		return -1;
-	}
-
 	queue = create_int_queue(dev, pipe, 1, length, buffer);
+	if (!queue)
+		return -1;
 
 	timeout = get_timer(0) + USB_TIMEOUT_MS(pipe);
 	while ((backbuffer = poll_int_queue(dev, queue)) == NULL)
-- 
2.1.0



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