Re: USB-UIRT

On 4/21/21 11:36 PM, Mary Strimel wrote:
 >
 >
 > On Wed, Apr 21, 2021 at 6:49 AM Bengt Martensson
 > <[email protected] <mailto:[email protected]>> wrote:
 >
 >
 >
 >     Right now, I cannot say anything simpler than "debug the sources,
 >     avaiable at Sourceforge". (You did look for interesting stuff in 
dmesg,
 >     didn't you?) Possibly someone else can? Sorry.
 >
 >
 > I say this without any expertise whatsoever, but I wonder if it is
 > problematic that dmesg is reporting the device as FTDI and there is a
 > corresponding ftdi_sio kernel driver loaded?
 >
 > usb-devices
 > T:  Bus=03 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#=  3 Spd=12  MxCh= 0
 > D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
 > P:  Vendor=0403 ProdID=f850 Rev=06.00
 > S:  Manufacturer=FTDI
 > S:  Product=USB-UIRT
 > C:  #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=100mA
 > I:  If#=0x0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=ftdi_sio
 >
 > mary@mythbox:~$ lsmod | grep ftdi
 > ftdi_sio               61440  1
 > usbserial              53248  3 ftdi_sio
 >
 > Is FTDI perhaps not part of the rc core, and therefore the device is not
 > registering an rc device at all?
 > It used to work correctly under Linux Mint 20 with kernel 5.4, but as I
 > mentioned earlier I do not recall dmesg saying anything about ftdi, and
 > now I am on kernel 5.8 and here it is. I would love to know which kernel
 > (if any) would support this usb-uirt device, while also supporting
 > hardware acceleration for my ryzen renoir apu. I think that means
 > downgrading my kernel but I would be happy to do that if I could achieve
 > both.
 >
 > I find the kernel.org <http://kernel.org> website to be inscrutable (to
 > me) for this purpose, so if anyone has any hints on how to research this
 > issue i would be very grateful.

FYI: FTDI is a firm (based in Glasgow, Scotland) that makes USB to 
serial converters. These are in general held in high regard. The kernel 
sees the device as a FTDI-chip. Usb-Uirt is not recognized by rc-core. 
So there is no reason to blame the kernel.

Try

$ sudo mode2 --driver=uirt2_raw --device=/dev/ttyUSB0 --keep-root 
--loglevel=10