diff mbox

USB: Accept bulk endpoints with 1024-byte maxpacket

Message ID Pine.LNX.4.44L0.1805031103230.2090-100000@iolanthe.rowland.org (mailing list archive)
State New, archived
Headers show

Commit Message

Alan Stern May 3, 2018, 3:04 p.m. UTC
Some non-compliant high-speed USB devices have bulk endpoints with a
1024-byte maxpacket size.  Although such endpoints don't work with
xHCI host controllers, they do work with EHCI controllers.  We used to
accept these invalid sizes (with a warning), but we no longer do
because of an unintentional change introduced by commit aed9d65ac327
("USB: validate wMaxPacketValue entries in endpoint descriptors").

This patch restores the old behavior, so that people with these
peculiar devices can use them without patching their kernels by hand.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Elvinas <elvinas@veikia.lt>
Fixes: aed9d65ac327 ("USB: validate wMaxPacketValue entries in endpoint descriptors")
CC: <stable@vger.kernel.org>

---


[as1866]


 drivers/usb/core/config.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)


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diff mbox

Patch

Index: usb-4.x/drivers/usb/core/config.c
===================================================================
--- usb-4.x.orig/drivers/usb/core/config.c
+++ usb-4.x/drivers/usb/core/config.c
@@ -191,7 +191,9 @@  static const unsigned short full_speed_m
 static const unsigned short high_speed_maxpacket_maxes[4] = {
 	[USB_ENDPOINT_XFER_CONTROL] = 64,
 	[USB_ENDPOINT_XFER_ISOC] = 1024,
-	[USB_ENDPOINT_XFER_BULK] = 512,
+
+	/* Bulk should be 512, but some devices use 1024: we will warn below */
+	[USB_ENDPOINT_XFER_BULK] = 1024,
 	[USB_ENDPOINT_XFER_INT] = 1024,
 };
 static const unsigned short super_speed_maxpacket_maxes[4] = {