Re: [PATCH v2 03/12] bus/fsl-mc: add support for 'driver_override' in the mc-bus

From: Andrew Lunn
Date: Thu May 07 2020 - 09:34:14 EST


On Thu, May 07, 2020 at 10:34:22AM +0300, Diana Craciun wrote:
> From: Bharat Bhushan <Bharat.Bhushan@xxxxxxx>
>
> This patch is required for vfio-fsl-mc meta driver to successfully bind
> layerscape container devices for device passthrough. This patch adds
> a mechanism to allow a layerscape device to specify a driver rather than
> a layerscape driver provide a device match.
>
> Example to allow a device (dprc.1) to specifically bind
> with driver (vfio-fsl-mc):
> - echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.1/driver_override
> - echo dprc.1 > /sys/bus/fsl-mc/drivers/fsl_mc_dprc/unbind
> - echo dprc.1 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind

Hi Bharat, Diana

grep -r "/driver_override" Documentation
Documentation/ABI/testing/sysfs-bus-rpmsg:What: /sys/bus/rpmsg/devices/.../driver_override
Documentation/ABI/testing/sysfs-bus-pci:What: /sys/bus/pci/devices/.../driver_override
Documentation/ABI/testing/sysfs-bus-platform:What: /sys/bus/platform/devices/.../driver_override
Documentation/ABI/testing/sysfs-bus-css:What: /sys/bus/css/devices/.../driver_override
Documentation/ABI/testing/sysfs-bus-vmbus:What: /sys/bus/vmbus/devices/.../driver_override
Documentation/ABI/testing/sysfs-bus-amba:What: /sys/bus/amba/devices/.../driver_override

Maybe it is time to move this into the core, and avoid yet another
implementation of driver_override_store() and driver_override_show()
functions etc.

Andrew