android/android_kernel_samsung_sm8650
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bus: fsl-mc: rescan devices if endpoint not found

Browse Source 
If the endpoint of a device is not yet probed on the bus, force
a rescan of the devices and retry to get a reference to the
endpoint device. If the device is still not found then we assume
it's in a different isolation context (container/DPRC) thus
unavailable and return a permission error.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Robert-Ionut Alexa <robert-ionut.alexa@nxp.com>
Link: https://lore.kernel.org/r/20210715140718.8513-7-laurentiu.tudor@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Laurentiu Tudor 2021-07-15 17:07:17 +03:00 committed by Greg Kroah-Hartman
parent 39243fc111
commit 8567494ceb
1 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
drivers/bus/fsl-mc/fsl-mc-bus.c
View File

@ -950,10 +950,28 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev)
* We know that the device has an endpoint because we verified by
* interrogating the firmware. This is the case when the device was not
* yet discovered by the fsl-mc bus, thus the lookup returned NULL.
* Differentiate this case by returning EPROBE_DEFER.
* Force a rescan of the devices in this container and retry the lookup.
*/
if (!endpoint) {
struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
if (mutex_trylock(&mc_bus->scan_mutex)) {
err = dprc_scan_objects(mc_bus_dev, true);
mutex_unlock(&mc_bus->scan_mutex);
}
if (err < 0)
return ERR_PTR(err);
}
endpoint = fsl_mc_device_lookup(&endpoint_desc, mc_bus_dev);
/*
* This means that the endpoint might reside in a different isolation
* context (DPRC/container). Not much to do, so return a permssion
* error.
*/
if (!endpoint)
return ERR_PTR(-EPROBE_DEFER);
return ERR_PTR(-EPERM);
return endpoint;
}