From: Hans de Goede <hdegoede@redhat.com>
Date: Tue, 5 May 2015 21:56:04 +0000 (+0200)
Subject: usb: Fix maxpacketsize for first descriptor read for low-speed usb devs
X-Git-Tag: v2015.07-rc2~285^2~14
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=2b338ef41127351089254b748de5cefd95c3e800;p=oweals%2Fu-boot.git

usb: Fix maxpacketsize for first descriptor read for low-speed usb devs

This fixes descriptor reading of lowspeed devices through ohci not working.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Marek Vasut <marex@denx.de>
---

diff --git a/common/usb.c b/common/usb.c
index a4820d3e94..1b26bfab36 100644
--- a/common/usb.c
+++ b/common/usb.c
@@ -946,13 +946,18 @@ static int usb_setup_descriptor(struct usb_device *dev, bool do_read)
 	 * send 64-byte GET-DEVICE-DESCRIPTOR request.  Since the descriptor is
 	 * only 18 bytes long, this will terminate with a short packet.  But if
 	 * the maxpacket size is 8 or 16 the device may be waiting to transmit
-	 * some more, or keeps on retransmitting the 8 byte header. */
+	 * some more, or keeps on retransmitting the 8 byte header.
+	 */
 
-	dev->descriptor.bMaxPacketSize0 = 64;	    /* Start off at 64 bytes  */
-	/* Default to 64 byte max packet size */
-	dev->maxpacketsize = PACKET_SIZE_64;
-	dev->epmaxpacketin[0] = 64;
-	dev->epmaxpacketout[0] = 64;
+	if (dev->speed == USB_SPEED_LOW) {
+		dev->descriptor.bMaxPacketSize0 = 8;
+		dev->maxpacketsize = PACKET_SIZE_8;
+	} else {
+		dev->descriptor.bMaxPacketSize0 = 64;
+		dev->maxpacketsize = PACKET_SIZE_64;
+	}
+	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
+	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
 
 	if (do_read) {
 		int err;