Re: [PATCH V3 1/3] gpio: Add virtio-gpio driver
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: 2021-06-14 10:21:30
Also in:
linux-gpio, lkml
On 10-06-21, 15:22, Arnd Bergmann wrote:
Can you give an example of how this would be hooked up to other drivers using those gpios. Can you give an example of how using the "gpio-keys" or "gpio-leds" drivers in combination with virtio-gpio looks like in the DT? Would qemu simply add the required DT properties to the device node that corresponds to the virtio device in this case? From what I can tell, both the mmio and pci variants of virtio can have their dev->of_node populated, but I don't see the logic in register_virtio_device() that looks up the of_node of the virtio_device that the of_gpio code then tries to refer to.
To be honest, I haven't tried this yet and I was expecting it to be already taken care of. I was relying on the DTB automatically generated by Qemu to get the driver probed and didn't have a look at it as well. I now understand that it won't be that straight forward. The same must be true for adding an i2c device to an i2c bus over virtio (The way I tested that earlier was by using the sysfs file to add a device to a bus). This may be something lacking generally for virtio-pci thing, not sure though. -- viresh _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization