On Tue, Dec 22, 2015 at 7:48 PM, Ramajayam S <ramajayam.samudi@xxxxxxxxx> wrote: > On Mon, Dec 14, 2015 at 11:17 PM, Ramajayam S > <ramajayam.samudi@xxxxxxxxx> wrote: >> On Mon, Dec 14, 2015 at 9:50 PM, Felipe Balbi <balbi@xxxxxx> wrote: >>> >>> hi, >>> >>> Ramajayam S <ramajayam.samudi@xxxxxxxxx> writes: >>>> Hi >>>> We are trying to enable g_serial in Intel platform and facing >>>> issue with RX path. >>>> >>>> stable kernel version: K3.14 >>> >>> you need to test with something more recent, like v4.3. If you are stuck >>> with Intel' v3.14 kernel, then you need to ask for support from Intel, >> ok >>> I'm afraid >>> >>>> configuration enabled: USB_G_SERIAL >>>> >>>> testing details: >>>> >>>> writing from device side(ttyS0) to Windows Host(com 11-g_serial): working fine >>>> >>>> from ttyS0: echo test > /dev/ttyGS0 -- received in comm 11 >>>> >>>> Typing any character from windows host pc(com 11 using teraterm) to >>>> device side: not working >>> >>> what do you mean not working ? What happens ? Got usbmon trace or some >>> usb sniffer ? >> We have profiled using USB SW analyzer, by pressing enter key from USB >> console(ttyGS0-com11 ) both the OUT/IN token sent from Host >> PC(windows). >> For IN token, >> Working case: device is responded with proper data(approx 20 bytes for >> command prompt display in ttyGSO-com11) and able to see raw data in >> function gs_write. >> Non-Working Case: device is responded with 1 byte of data and able >> to see raw data in function gs_write (no response in command prompt >> display --ttyGS0-com11) > If we had print in n_tty_read function(after job_control function), > console(ttyGS0-Com11) is working fine with double key press. > 1st key press(enter key): user space is requesting to read 512 bytes > of data instead of 1 byte -- non working scenario > 2nd key Press(enter key): user space is requesting to read 1 byte of > data -- working scenario Issue is root caused with virtualization code(virtual usb). collision is happened b/w virtual usb request and g_serial terminal request in tty layer(read). > Ramajayam S >>> >>> -- >>> balbi -- 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
