From: Robert Hodaszi <robert.hodaszi@digi.com>
To: Oliver Neukum <oneukum@suse.com>, linux-usb@vger.kernel.org
Subject: Re: Handling incoming ZLP in cdc-wdm
Date: Thu, 27 Mar 2025 16:23:15 +0100 [thread overview]
Message-ID: <ad9bed5e-4d40-4c32-9ae1-96dcf09cf3af@digi.com> (raw)
In-Reply-To: <42118b9b-7aa1-4559-824a-2c2ec70ea7d8@suse.com>
On Thursday, 27.03.2025 at 14:21 +0100, Oliver Neukum <oneukum@suse.com> wrote:
>
> Arguably the interrupt handler should set the flag for a readable result only
> if indeed there is data in the buffer. Could you try the attached patch?
>
> Regards
> Oliver
I think, that will not work. With this patch, if a ZLP comes in, WDM_READ is not set, so wdm_read() won't submit another read urb if resp_count is not zero (won't call service_outstanding_interrupt), and we are not doing here, in wdm_in_callback neither. So the receiving just gets stuck.
That's exactly the reason I did what I did in the patch I sent.
Best regards,
Robert Hodaszi
next prev parent reply other threads:[~2025-03-27 15:55 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-26 15:50 Handling incoming ZLP in cdc-wdm Robert Hodaszi
2025-03-27 13:21 ` Oliver Neukum
2025-03-27 15:23 ` Robert Hodaszi [this message]
-- strict thread matches above, loose matches on Subject: below --
2025-03-26 16:03 Hodaszi, Robert
2025-03-27 13:01 ` Robert Hodaszi
2025-03-27 13:24 ` Oliver Neukum
2025-03-27 15:27 ` Robert Hodaszi
2025-03-31 9:59 ` Oliver Neukum
2025-04-02 11:57 ` Robert Hodaszi
2025-04-02 14:01 ` Oliver Neukum
2025-04-02 15:01 ` Robert Hodaszi
2025-04-02 19:13 ` Oliver Neukum
2025-04-03 12:25 ` Robert Hodaszi
[not found] ` <898977f7-3882-4ffe-8833-c44f06914337@digi.com>
2025-04-03 12:58 ` Oliver Neukum
2025-04-03 14:42 ` Robert Hodaszi
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