Ferry Toth wrote: > Hi > > Op 16-04-2021 om 00:23 schreef Thinh Nguyen: >> Thinh Nguyen wrote: >>> From: Yu Chen <chenyu56@xxxxxxxxxx> >>> From: John Stultz <john.stultz@xxxxxxxxxx> >>> >>> According to the programming guide, to switch mode for DRD controller, >>> the driver needs to do the following. >>> >>> To switch from device to host: >>> 1. Reset controller with GCTL.CoreSoftReset >>> 2. Set GCTL.PrtCapDir(host mode) >>> 3. Reset the host with USBCMD.HCRESET >>> 4. Then follow up with the initializing host registers sequence >>> >>> To switch from host to device: >>> 1. Reset controller with GCTL.CoreSoftReset >>> 2. Set GCTL.PrtCapDir(device mode) >>> 3. Reset the device with DCTL.CSftRst >>> 4. Then follow up with the initializing registers sequence >>> >>> Currently we're missing step 1) to do GCTL.CoreSoftReset and step 3) of >>> switching from host to device. John Stult reported a lockup issue seen >>> with HiKey960 platform without these steps[1]. Similar issue is observed >>> with Ferry's testing platform[2]. >>> >>> So, apply the required steps along with some fixes to Yu Chen's and John >>> Stultz's version. The main fixes to their versions are the missing wait >>> for clocks synchronization before clearing GCTL.CoreSoftReset and only >>> apply DCTL.CSftRst when switching from host to device. >>> >>> [1] >>> https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/20210108015115.27920-1-john.stultz@xxxxxxxxxx/__;!!A4F2R9G_pg!PW9Jbs4wv4a_zKGgZHN0FYrIpfecPX0Ouq9V3d16Yz-9-GSHqZWsfBAF-WkeqLhzN4i3$ >>> >>> [2] >>> https://urldefense.com/v3/__https://lore.kernel.org/linux-usb/0ba7a6ba-e6a7-9cd4-0695-64fc927e01f1@xxxxxxxxx/__;!!A4F2R9G_pg!PW9Jbs4wv4a_zKGgZHN0FYrIpfecPX0Ouq9V3d16Yz-9-GSHqZWsfBAF-WkeqGeZStt4$ >>> >>> >>> Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> >>> Cc: Ferry Toth <fntoth@xxxxxxxxx> >>> Cc: Wesley Cheng <wcheng@xxxxxxxxxxxxxx> >>> Cc: <stable@xxxxxxxxxxxxxxx> >>> Fixes: 41ce1456e1db ("usb: dwc3: core: make dwc3_set_mode() work >>> properly") >>> Signed-off-by: Yu Chen <chenyu56@xxxxxxxxxx> >>> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> >>> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> >>> --- >>> Changes in v3: >>> - Check if the desired mode is OTG, then keep the old flow >>> - Remove condition for OTG support only since the device can still be >>> configured DRD host/device mode only >>> - Remove redundant hw_mode check since __dwc3_set_mode() only applies >>> when >>> hw_mode is DRD >>> Changes in v2: >>> - Initialize mutex per device and not as global mutex. >>> - Add additional checks for DRD only mode >>> >>> drivers/usb/dwc3/core.c | 27 +++++++++++++++++++++++++++ >>> drivers/usb/dwc3/core.h | 5 +++++ >>> 2 files changed, 32 insertions(+) >>> >> Hi John, >> >> If possible, can you run a test with this version on your platform? >> >> Thanks, >> Thinh >> > I tested this on edison-arduino with this patch on top of usb-next > (5.12-rc7 + "increase BESL baseline to 6" to prevent throttling"). > > On this platform there is a physical switch to switch roles. With this > patch I find: > > - switch to host mode always works fine > > - switch to gadget mode I need to flip the switch 3x (gadget-host-gadget). > > An error message appears on the gadget side "dwc3 dwc3.0.auto: timed out > waiting for SETUP phase" appears, but then the device connects to my PC, > no throttling. > > - alternatively I can switch to gadget 1x and then unplug/replug the cable. > > No error message and connects fine. > > - if I flip the switch only once, on the PC side I get: > > kernel: usb 1-5: new high-speed USB device number 18 using xhci_hcd > kernel: usb 1-5: New USB device found, idVendor=1d6b, > idProduct=0104, bcdDevice= 1.00 kernel: usb 1-5: New USB device > strings: Mfr=1, Product=2, SerialNumber=3 kernel: usb 1-5: Product: > USBArmory Gadget kernel: usb 1-5: Manufacturer: USBArmory kernel: > usb 1-5: SerialNumber: 0123456789abcdef kernel: usb 1-5: can't set > config #1, error -110 The device failed at set_configuration() request and timed out. It probably timed out from the status stage looking at the device err print. > > Then if I wait long enough on the gadget side I get: > > root@yuna:~# ifconfig > > usb0: flags=-28605<UP,BROADCAST,RUNNING,MULTICAST,DYNAMIC> mtu 1500 > inet 169.254.119.239 netmask 255.255.0.0 broadcast 169.254.255.255 > inet6 fe80::a8bb:ccff:fedd:eef1 prefixlen 64 scopeid 0x20<link> > ether aa:bb:cc:dd:ee:f1 txqueuelen 1000 (Ethernet) RX packets 490424 > bytes 735146578 (701.0 MiB) RX errors 0 dropped 191 overruns 0 frame > 0 TX packets 35279 bytes 2532746 (2.4 MiB) TX errors 0 dropped 0 > overruns 0 carrier 0 collisions 0 > > (correct would be: inet 10.42.0.221 netmask 255.255.255.0 broadcast > 10.42.0.255) > > So much improved now, but it seems I am still missing something on plug. > That's great! We can look at it further. Can you capture the tracepoints of the issue. Also, can you try with mass_storage gadget to see if the result is the same? Thanks, Thinh
