Hi Phil, > What about using virtio-gpio & bitbang I2C? > > - virtio-gpio > https://lore.kernel.org/qemu-devel/20201127182917.2387-5-i...@metux.net/ > > - bitbang I2C already in: hw/i2c/bitbang_i2c.c Sorry for the delay.
That looks like it might be doable with a bit more work creating the ACPI entries for the bitbang I2C. This definitely seems more appropriate on the ARM_VIRT platform instead of putting a specific controller in. For my uses, I will have to stick with the designware controller since it matches the system I'm emulating a little more closely. We can hold back the designware stuff until another SoC platform is interested in using this controller (since it seems like it is a common one). Hopefully someone will find another use for the controller patches someday. Thanks again for looking at our patches. -Chris On Wed, Jan 26, 2022 at 3:42 PM Philippe Mathieu-Daudé <f4...@amsat.org> wrote: > +Enrico Weigelt > > On 26/1/22 19:03, Peter Maydell wrote: > > On Wed, 26 Jan 2022 at 17:12, Chris Rauer <cra...@google.com> wrote: > >> > >>> I need to see a pretty strong justification for why we should be > >>> adding new kinds of devices to the virt machine, > >> > >> The designware i2c controller is a very common controller on many > >> ARM SoCs. It has device tree bindings and ACPI bindings which > >> makes it ideal for this platform. > > > > No, I mean, why do we need an i2c controller on the virt > > board at all ? > > > >>> Forgot to mention, but my prefered approach for providing > >>> an i2c controller on the virt board would be to have a > >>> PCI i2c controller: that way users who do need it can plug it > >>> in with a -device command line option, and users who don't > >>> need it never have to worry about it. > > > >>> (We seem to have an ICH9-SMB PCI device already; I have no idea if > it's suitable.) > >> I didn't find that device suitable because it is part of the Intel > >> Southbridge, which may have some Intel platform quirks, and > >> we don't need all the things in that IO hub. > > > > That's a pity. Is there a different PCI I2C controller we could model ? > > What about using virtio-gpio & bitbang I2C? > > - virtio-gpio > https://lore.kernel.org/qemu-devel/20201127182917.2387-5-i...@metux.net/ > > - bitbang I2C already in: hw/i2c/bitbang_i2c.c > > Regards, > > Phil. >
