[RFC PATCH 0/2] Add test to verify probe of devices from discoverable busses on DT platforms

From: "Nícolas F. R. A. Prado" <nfraprado@collabora.com>
To: Shuah Khan <shuah@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Bjorn Helgaas <bhelgaas@google.com>
Cc: devicetree@vger.kernel.org, linux-pci@vger.kernel.org,
	linux-usb@vger.kernel.org, "Rob Herring" <robh+dt@kernel.org>,
	linux-kselftest@vger.kernel.org, kernel@collabora.com,
	"Nícolas F. R. A. Prado" <nfraprado@collabora.com>,
	linux-kernel@vger.kernel.org
Subject: [RFC PATCH 0/2] Add test to verify probe of devices from discoverable busses on DT platforms
Date: Tue, 24 Oct 2023 17:17:58 -0400	[thread overview]
Message-ID: <20231024211818.365844-1-nfraprado@collabora.com> (raw)

This is part of an effort to improve detection of regressions impacting
device probe on all platforms. The recently merged DT kselftest [1]
detects probe issues for all devices described statically in the DT.
That leaves out devices discovered at run-time from discoverable busses.

This is where this test comes in. All of the devices that are connected
through discoverable busses (ie USB and PCI), and which are internal and
therefore always present, can be described in a per-platform file so
they can be checked for. The test will check that the device has been
instantiated and bound to a driver.

Patch 1 introduces the test. Patch 2 adds the test definitions for the
google,spherion machine (Acer Chromebook 514) as an example.

This is the sample output from the test running on Spherion:

TAP version 13
 Using board file:  boards/google,spherion
1..10
ok 1 usb.camera.0.device
ok 2 usb.camera.0.driver
ok 3 usb.camera.1.device
ok 4 usb.camera.1.driver
ok 5 usb.bluetooth.0.device
ok 6 usb.bluetooth.0.driver
ok 7 usb.bluetooth.1.device
ok 8 usb.bluetooth.1.driver
ok 9 pci.wifi.device
ok 10 pci.wifi.driver
 Totals: pass:10 fail:0 xfail:0 xpass:0 skip:0 error:0

[1] https://lore.kernel.org/all/20230828211424.2964562-1-nfraprado@collabora.com/

Nícolas F. R. A. Prado (2):
  kselftest: Add test to verify probe of devices from discoverable
    busses
  kselftest: devices: Add board file for google,spherion

 tools/testing/selftests/Makefile              |   1 +
 tools/testing/selftests/devices/.gitignore    |   1 +
 tools/testing/selftests/devices/Makefile      |   8 +
 .../selftests/devices/boards/google,spherion  |   3 +
 .../devices/test_discoverable_devices.sh      | 165 ++++++++++++++++++
 5 files changed, 178 insertions(+)
 create mode 100644 tools/testing/selftests/devices/.gitignore
 create mode 100644 tools/testing/selftests/devices/Makefile
 create mode 100644 tools/testing/selftests/devices/boards/google,spherion
 create mode 100755 tools/testing/selftests/devices/test_discoverable_devices.sh

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2.42.0