public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: sangsu <sangsu@gmail.com>
To: dbrownell@users.sourceforge.net, gregkh@suse.de,
	stern@rowland.harvard.edu, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] USB: g_file_storage: fix handling zero-length packet
Date: Sat, 06 Sep 2008 00:51:10 -0400	[thread overview]
Message-ID: <48C20C3E.20306@gmail.com> (raw)

According to "CH 5.5.3. Control Transfer Packet Size Constraints",
Zero-length packet should be sent when the last data payload size
is equal to the endpoint's MaxPacketSize. This patch helps
g_file_storage send zero-length packet properly.

This is tested in s3c2440/s5c7329 architectures and works well.

Signed-off-by: SangSu Park<sangsu@gmail.com>
---
driver/usb/gadget/file_storage.c | 3++-
1 files changed, 2 insertion(+), 1 deletions(-)

--- a/drivers/usb/gadget/file_storage.c	2008-09-01 11:13:03.000000000 -0400
+++ b/drivers/usb/gadget/file_storage.c	2008-09-01 11:16:41.000000000 -0400
@@ -1463,7 +1463,8 @@
	if (rc >= 0 && rc != DELAYED_STATUS) {
		rc = min(rc, w_length);
		fsg->ep0req->length = rc;
-		fsg->ep0req->zero = rc < w_length;
+		fsg->ep0req->zero = rc < w_length
+			&& (rc % gadget->ep0->maxpacket) == 0;
		fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
				"ep0-in" : "ep0-out");
		rc = ep0_queue(fsg);

             reply	other threads:[~2008-09-06  4:51 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-06  4:51 sangsu [this message]
2008-09-06 20:27 ` [PATCH] USB: g_file_storage: fix handling zero-length packet Alan Stern
2008-09-07  4:32   ` David Brownell

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=48C20C3E.20306@gmail.com \
    --to=sangsu@gmail.com \
    --cc=dbrownell@users.sourceforge.net \
    --cc=gregkh@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=stern@rowland.harvard.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox