Hej, On 2022-08-25 23:35:33 -0600, Ashok Reddy Soma wrote: > We are seeing timing issues with transcend usb sticks. These devices > seems to require more time than regular devices for the control messages > to reach device. Add 1ms delay before sending control message to fix > trancend device detection issue.
I suspect I see something similar with the DWC3 controller on Apple M1/M2 devices. It seems to be related to USB full speed devices with bMaxPacketSize0 of 8. Failing devices are so only keyboards since that is a device everyone will connect when using a Mac Mini as desktop. I can reproduce the issue with older Logitech Unifying Receiver wireless keyboard/mouse dongles (bcdDevice 12.03 or 12.10). I could also resolve the issue with random 'mdelay(1);'. I chased the cause of the issue down to the initial USB descriptor read to parse 'bMaxPacketSize0' in usb_setup_descriptor(). Please test if adding the delay after the get_descriptor_len() call in usb_setup_descriptor() is enough. On the Apple silicon devices reducing the read size from 64 byte to 8 resolves the issue as well. Please try attached work-in-progress patch (comment and commit message are not finalized). HTH Janne > Signed-off-by: Ashok Reddy Soma <ashok.reddy.s...@amd.com> > --- > > common/usb.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/common/usb.c b/common/usb.c > index 6fcf1e8428..3fae32b048 100644 > --- a/common/usb.c > +++ b/common/usb.c > @@ -241,6 +241,12 @@ int usb_control_msg(struct usb_device *dev, unsigned int > pipe, > request, requesttype, value, index, size); > dev->status = USB_ST_NOT_PROC; /*not yet processed */ > > + /* Timing issues are observed with transcend usb sticks such as > + * “Transcend Jetflash 350 USB2.0". Add 1ms delay for the usb > + * device to get detected. > + */ > + mdelay(1); Please let's try to avoid this. I noticed a slowdown of USB probing with an hub with 4 devices connected. Since Apple silicon devices are desktop style machines I expect it's not uncommon to see systems with many USB devices. > + > err = submit_control_msg(dev, pipe, data, size, setup_packet); > if (err < 0) > return err; > -- > 2.17.1 >
>From df9e5b78687fc4eed4988f99d3f195cba8b227e1 Mon Sep 17 00:00:00 2001 From: Janne Grunau <j...@jannau.net> Date: Fri, 26 Aug 2022 00:01:15 +0200 Subject: [PATCH 1/1] usb: request on 8 bytes for USB_SPEED_FULL bMaxPacketSize0 probing Fixes probing of Logitech Unifying receivers (bcdDevice 12.03 or 12.10) with bMaxPacketSize0 == 8 on Apple silicon SoCs using DWC3 controllers. Signed-off-by: Janne Grunau <j...@jannau.net> --- common/usb.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/common/usb.c b/common/usb.c index aad13fd9c557..2d6d782f9103 100644 --- a/common/usb.c +++ b/common/usb.c @@ -999,8 +999,17 @@ static int usb_setup_descriptor(struct usb_device *dev, bool do_read) * the number of packets in addition to the number of bytes. * A request for 64 bytes of data with the maxpacket guessed * as 64 (above) yields a request for 1 packet. + * + * The DWC3 controller integrated into Apple silicon SoCs like + * the M1 and M2 does not like to read 64 bytes for devices with + * bMaxPacketSize0 == 8. request only 8 bytes which should also + * result in a single packet. + * Fixes probing errors with Logitech Unifying receivers with + * bcdDevice 12.03 or 12.10. + * A delay of 1 ms after this get_descriptor_len() call fixes + * the issue as well. */ - err = get_descriptor_len(dev, 64, 8); + err = get_descriptor_len(dev, 8, 8); if (err) return err; } -- 2.35.1
