> -----Original Message----- > From: Felipe Balbi [mailto:balbi@xxxxxx] > Sent: Monday, November 09, 2015 12:33 PM > To: McCauley, Ben <Ben.McCauley@xxxxxxxxxx>; John Youn > <John.Youn@xxxxxxxxxxxx>; gregkh@xxxxxxxxxxxxxxxxxxx > Cc: linux-usb@xxxxxxxxxxxxxxx; Schroeder, Jay <Jay.Schroeder@xxxxxxxxxx> > Subject: RE: [PATCH] USB: DCW3: GADGET: Set Correct Max Speed > > > Hi, > > "McCauley, Ben" <Ben.McCauley@xxxxxxxxxx> writes: > >> > Ben is talking about setting the gadget->max_speed, which is > >> > hard-coded in dwc3 to USB_SPEED_SUPER. > >> > > >> > For this core, the maximum supported speed may not actually be > >> > super speed. Many customers choose to use the 3.0 core in 2.0-only > >> > mode with a HS phy. > >> > >> yeah, I got all that. But we still have the problem of metastability > >> for anything <2.20a. For those cores, we just cannot mess around with > >> any of these settings (STAR 9000525659, if you wanna check). > >> > >> > And with the 3.1 core, it my be integrated in a system that is > >> > HS-only, SS (gen1), or SSP (gen2) capable. So the > >> > gadget->max_speed needs to be set correctly based on some > >> > user-defined or detected value. > >> > > >> > We have a similar change in our local tree for 3.1, except we set > >> > it based on GHWPARAMS3.SSPHY_INTERFACE. But I think it makes > sense > >> > to > >> set > >> > it from dwc->maximum_speed as well, for testing or to override it. > >> > >> My other fear is about people setting this wrongly and later > >> complaining that it's not working. I would very much prefer your > >> patch which detects whether SSPHY_INTERFACE is around, however that > won't always be correct. > >> > >> I just noticed that in our USB2-only SoC (AM437x), SSPHY_INTERFACE is > >> set to > >> 1 even though this SoC does _not_ have any USB3 capabilities. > >> > >> GHWPARAMS3 = 0x10420085 > >> > >> I actually tested this problem as listed above and connected my > >> USB2-only SoC to a windows box (both USB2 and USB3 hosts) and did not > >> see any such error messages. Any ideas why you have problems an I don't > ? > > > > Using an actual 3.0 device I have been able to generate the following > > message "This device can perform faster", when connecting to one of > > the 2.0 ports on the same PC. It might have something to do with the > > organization of the USB hubs In my computer making windows think that > > a 3.0 device was connected to a 2.0 when the reality is swapped when > connecting the gadget. > > if you're connecting a USB 3.0 device to a USB 2.0 port, windows is doing the > right thing. It's telling you "if you want to use the full potential of this device, > you should connect it to one of your available USB 3.0 ports". > > Neither Windows nor dwc3 are wrong in this case. > > >> Maybe, all we have to do is avoid adding a SuperSpeed USB Capability > >> descriptor if we didn't negotiate for superspeed. All the rest can > >> remain the > >> same: > >> > >> diff --git a/drivers/usb/gadget/composite.c > >> b/drivers/usb/gadget/composite.c index 8b14c2a13ac5..672ae6bfcad8 > >> 100644 > >> --- a/drivers/usb/gadget/composite.c > >> +++ b/drivers/usb/gadget/composite.c > >> @@ -547,9 +547,8 @@ static int count_configs(struct usb_composite_dev > >> *cdev, unsigned type) static int bos_desc(struct usb_composite_dev > >> *cdev) { > >> struct usb_ext_cap_descriptor *usb_ext; > >> - struct usb_ss_cap_descriptor *ss_cap; > >> - struct usb_dcd_config_params dcd_config_params; > >> struct usb_bos_descriptor *bos = cdev->req->buf; > >> + struct usb_gadget *gadget = cdev->gadget; > >> > >> bos->bLength = USB_DT_BOS_SIZE; > >> bos->bDescriptorType = USB_DT_BOS; @@ -569,33 +568,38 @@ static > >> int bos_desc(struct usb_composite_dev > >> *cdev) > >> usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT; > >> usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT | > >> USB_BESL_SUPPORT); > >> > >> - /* > >> - * The Superspeed USB Capability descriptor shall be implemented by > >> all > >> - * SuperSpeed devices. > >> - */ > >> - ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength); > >> - bos->bNumDeviceCaps++; > >> - le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE); > >> - ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE; > >> - ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY; > >> - ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE; > >> - ss_cap->bmAttributes = 0; /* LTM is not supported yet */ > >> - ss_cap->wSpeedSupported = > >> cpu_to_le16(USB_LOW_SPEED_OPERATION | > >> + if (gadget->speed >= USB_SPEED_SUPER) { > >> + struct usb_ss_cap_descriptor *ss_cap; > >> + struct usb_dcd_config_params dcd_config_params; > >> + > >> + /* > >> + * The Superspeed USB Capability descriptor shall be > >> implemented > >> + * by all SuperSpeed devices. > >> + */ > >> + ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength); > >> + bos->bNumDeviceCaps++; > >> + le16_add_cpu(&bos->wTotalLength, > >> USB_DT_USB_SS_CAP_SIZE); > >> + ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE; > >> + ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY; > >> + ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE; > >> + ss_cap->bmAttributes = 0; /* LTM is not supported yet */ > >> + ss_cap->wSpeedSupported = > >> cpu_to_le16(USB_LOW_SPEED_OPERATION | > >> USB_FULL_SPEED_OPERATION | > >> USB_HIGH_SPEED_OPERATION | > >> USB_5GBPS_OPERATION); > >> - ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION; > >> + ss_cap->bFunctionalitySupport = > >> USB_LOW_SPEED_OPERATION; > >> > >> - /* Get Controller configuration */ > >> - if (cdev->gadget->ops->get_config_params) > >> - cdev->gadget->ops- > >> >get_config_params(&dcd_config_params); > >> - else { > >> + /* Get Controller configuration */ > >> dcd_config_params.bU1devExitLat = > >> USB_DEFAULT_U1_DEV_EXIT_LAT; > >> dcd_config_params.bU2DevExitLat = > >> cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT); > >> + > >> + if (cdev->gadget->ops->get_config_params) > >> + cdev->gadget->ops- > >> >get_config_params(&dcd_config_params); > >> + > >> + ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat; > >> + ss_cap->bU2DevExitLat = > >> + dcd_config_params.bU2DevExitLat; > >> } > >> - ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat; > >> - ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat; > >> > >> return le16_to_cpu(bos->wTotalLength); } > >> > >> Can you see if this solves the issue you're having ? > >> > > > > I can confirm that this does resolve Windows reporting a that a 3.0 > > device was connected to a non 3.0 port. > > > > I am concerned that though this fixes the issue, it could result in > > 3.0 devices not reporting themselves as a 3.0 device when connected to > > a 2.0 port. > > right, I was thinking about the same thing after I sent this. But can you really > describe the problem you're having ? Is your device SuperSpeed capable or > not ? Are you connecting it to a Highspeed port or Superspeed port ? > The device is not SuperSpeed capable and the issue comes up when connecting the device to a SuperSpeed port. The crux of the issue is that I have a coworker laptop which when connected to the device the device receives a U2 command multiple times and after cycling through suspend and resume a couple times finalizes in the suspend state. So that reality is that there are two issues, 1. PC reports 3.0 when the device does not support 3.0. This results in a confusing user experience and worth resolving. 2. Device initialized in suspend resulting in the g_hid module not functioning. The first patch fixed this as a side effect. This is the actual issue I am working to fix. This does not happen on all SS capable computers. I have only found the one model so far. > -- > balbi ________________________________ CONFIDENTIALITY NOTICE: This email and any attachments are for the sole use of the intended recipient(s) and contain information that may be confidential and/or legally privileged. If you have received this email in error, please notify the sender by reply email and delete the message. Any disclosure, copying, distribution or use of this communication (including attachments) by someone other than the intended recipient is prohibited. Thank you. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
