From ac3abf0b7d3a0c59a8a6697efbe9187692f199f0 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@rwth-aachen.de> Date: Tue, 22 Dec 2015 01:21:04 +0100 Subject: [PATCH] usb: musb: Fix hub port setting for SPLIT transactions MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The ifdef'ed Linux kernel code uses the 1 based port number, whereas U-Boot puts a 0 based port number into the register. The reason the 0 based port number apparently works can probably be taken from the USB 2.0 spec: 8.4.2.2 Start-Split Transaction Token ... The host must correctly set the port field for single and multiple TT hub implementations. A single TT hub implementation *may ignore* the port field. Actually, as far as I understand, a multi TT hub defaults to single TT (bAlternateSetting: 0) until switched via SetInterface, so even "port 42" would work. The change was verified by hardcoding the port number to a wrong value, SPLIT transactions kept working (although using a DWC2 instead of MUSB). Tested hubs are the RPi onboard SMC9514 and an external "05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB". The former is a multi TT hub, the latter single TT only. Addendum: Tested on sunxi/MUSB by Hans de Goede Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Hans de Goede <hdegoede@redhat.com> --- drivers/usb/musb-new/musb_host.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/musb-new/musb_host.c b/drivers/usb/musb-new/musb_host.c index 70f8a994d1..2515447308 100644 --- a/drivers/usb/musb-new/musb_host.c +++ b/drivers/usb/musb-new/musb_host.c @@ -2098,7 +2098,7 @@ int musb_urb_enqueue( &hubaddr, &portnr); qh->h_addr_reg = hubaddr; - qh->h_port_reg = portnr - 1; + qh->h_port_reg = portnr; } #endif } -- 2.39.5