Re: [PATCH] usbnet: Set duplex status to unknown in the absence of MII
From: Andrew Lunn <andrew@lunn.ch>
Date: 2025-07-23 13:05:33
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On Wed, Jul 23, 2025 at 09:29:26AM +0800, yicongsrfy@163.com wrote:
On Tue, 22 Jul 2025 15:06:37 +0200 [thread overview] Andrew [off-list ref] wrote:quoted
On Tue, Jul 22, 2025 at 10:09:33AM +0800, yicongsrfy@163.com wrote:quoted
Thanks for your reply! According to the "Universal Serial Bus Class Definitions for Communications Devices v1.2": In Section 6.3, which describes notifications such as NetworkConnection and ConnectionSpeedChange, there is no mention of duplex status.In particular, for ConnectionSpeedChange, its data payload only contains two 32-bit unsigned integers, corresponding to the uplink and downlink speeds.Thanks for checking this. Just one more question. This is kind of flipping the question on its head. Does the standard say devices are actually allowed to support 1/2 duplex? Does it say they are not allowed to support 1/2 duplex? If duplex is not reported, maybe it is because 1/2 duplex is simply not allowed, so there is no need to report it.No, the standard does not mention anything about duplex at all.
O.K. So please set duplex to unknown.
Andrew