On Thu, 25 Jul 2013, Felipe Balbi wrote: > On Thu, Jul 25, 2013 at 03:44:20PM -0400, Alan Stern wrote: > > On Thu, 25 Jul 2013, Greg KH wrote: > > > > > On Tue, Jul 02, 2013 at 08:13:52PM -0700, Jack Pham wrote: > > > > From: Manu Gautam <mgautam@xxxxxxxxxxxxxx> > > > > > > > > The USB Embedded High-speed Host Electrical Test (EHSET) defines the > > > > SINGLE_STEP_SET_FEATURE test as follows: > > > > > > > > 1) The host enumerates the test device with VID:0x1A0A, PID:0x0108 > > > > 2) The host sends the SETUP stage of a GetDescriptor(Device) > > > > 3) The device ACKs the request > > > > 4) The host issues SOFs for 15 seconds allowing the test operator to > > > > raise the scope trigger just above the SOF voltage level > > > > 5) The host sends the IN packet > > > > 6) The device sends data in response, triggering the scope > > > > 7) The host sends an ACK in response to the data > > > > > > > > This patch adds additional handling to the EHCI hub driver and allows > > > > the EHSET driver to initiate this test mode by issuing a a SetFeature > > > > request to the root hub with a Test Selector value of 0x06. From there > > > > it mimics ehci_urb_enqueue() but separately submits QTDs for the > > > > SETUP and DATA/STATUS stages in order to insert a delay in between. > > > > > > > > Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx> > > > > Signed-off-by: Jack Pham <jackp@xxxxxxxxxxxxxx> > > > > > > Alan, any thoughts about this patch? > > > > Sorry, this slipped my mind. > > > > It looks okay. I haven't tested it yet (and it's so specialized that > > it probably will never receive very much testing). It is somewhat > > fragile, in that it copies part of usbcore into ehci-hcd; updates to > > the core will have to be mirrored in the driver. > > > > On the other hand, there's no real reason to reject it, and it could > > end up helping people who want to test new USB devices. So... > > > > Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> > > Wait a minute, didn't we discuss a while back that these test features > should be built into usbcore so that we could have a usbcv clone for > linux ? There's no way this can be built into the core. This test requires the behavior of the host controller to be modified at a low level (introducing a 15-second delay between the Setup and Data stages of a control transfer). Only the HCD can do that. Besides, doesn't USB-CV install its own version of Windows' EHCI driver while it runs its tests? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
