Re: Making a kmod

On Sat, 18 Oct 2025 17:26:37 -0400
Aryeh Friedman <aryeh.friedman@gmail.com> wrote:

> On Sat, Oct 18, 2025 at 5:17 PM Milan Obuch <freebsd-hackers@dino.sk>
> wrote:
> >
> > On Sat, 18 Oct 2025 17:05:00 -0400
> > Aryeh Friedman <aryeh.friedman@gmail.com> wrote:
> >  
> > > I need to make a kernel mod that connects to a Vantech 2S1P PCIe
> > > serial/par. combo card that has a 74LS02 hooked up to in roughly
> > > the same way that I2C is interfaced to in lpbb(4) is for bit
> > > banging on the LS02.   I got /dev/lpt0, etc. on the bhyve host I
> > > am used and have passed it through and the guest sees the 2S1P
> > > but thats where I stand and to farther it appears I neeed a kmod
> > > since the guest is seeing the device but not attaching a driver:
> > >
> > > pci0: <simple comms, UART> at device 3.0 (no driver attached)
> > > pci0: <simple comms, UART> at device 5.0 (no driver attached)
> > > pci0: <simple comms, parallel port> at device 6.0 (no driver
> > > attached)
> > >
> > > none0@pci0:0:3:0:    class=0x070002 rev=0x00 hdr=0x00
> > > vendor=0x9710 device=0x9912 subvendor=0xa000 subdevice=0x1000
> > >     vendor     = 'MosChip Semiconductor Technology Ltd.'
> > >     device     = 'PCIe 9912 Multi-I/O Controller'
> > >     class      = simple comms
> > >     subclass   = UART
> > > none1@pci0:0:5:0:    class=0x070002 rev=0x00 hdr=0x00
> > > vendor=0x9710 device=0x9912 subvendor=0xa000 subdevice=0x1000
> > >     vendor     = 'MosChip Semiconductor Technology Ltd.'
> > >     device     = 'PCIe 9912 Multi-I/O Controller'
> > >     class      = simple comms
> > >     subclass   = UART
> > > none2@pci0:0:6:0:    class=0x070103 rev=0x00 hdr=0x00
> > > vendor=0x9710 device=0x9912 subvendor=0xa000 subdevice=0x2000
> > >     vendor     = 'MosChip Semiconductor Technology Ltd.'
> > >     device     = 'PCIe 9912 Multi-I/O Controller'
> > >     class      = simple comms
> > >     subclass   = parallel port
> > >  
> >
> > Did you looked at puc driver? Off my head, MosChip devices are
> > there, among other ones, some time ago I was able to add new board
> > with simple addition of its description. I do not have the details
> > of the board and necessary modification. I think it is really worth
> > of some test, puc driver is designed for such cards.  
> 
> Spent most of last night messing around with puc, ppt, etc. and got no
> where even added this to /usr/src/sys/dev/puc/pucdata.c:
> 
> { 0x9710, 0x9912, 0, 0, "MosChip Semiconductor Technology Ltd. PCIe
> 9912 Multi-I/O Controller", PUC_PORT_2S1P, 0, 0, 0 },
> 

What did you see in dmesg with this modification? Was there any change
in comparison with original kernel without this?

If not, then try 'wildcard match', using modified definition

{ 0x9710, 0x9912, 0xffff, 0,
  "MosChip Semiconductor Technology Ltd. PCIe 9912 Multi-I/O Controller",
  PUC_PORT_2S1P, 0, 0, 0 },

Milan