helpers: Introduce assert_usb_probed

Current bootrr helpers, assert_device_present and assert_driver_present,
use driver and device names, both of which are not part of the kernel's
stable ABI and end up requiring extra maintenance whenever those names
are changed, in order to check for the expected name on each kernel
version.

Introduce a new helper, assert_usb_probed, that verifies a USB device
has been probed, taking as parameters the device's hardware identifying
properties, which are documented kernel ABI: idVendor, idProduct,
bcdDevice, bDeviceClass, bDeviceSubClass, bDeviceProtocol,
bInterfaceClass, bInterfaceSubClass, bInterfaceProtocol,
bInterfaceNumber.

A 'count' parameter is also required, to inform the number of devices
matching these criteria that should have been probed. This allows the
test to verify the probe of multiple identical devices.

A '*' can be used as wildcard for any of the matching fields as
necessary.

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>

helpers/assert_usb_probed

@@ -0,0 +1,61 @@
+#!/bin/sh
+
+. bootrr
+
+TEST_CASE_ID="$1"
+COUNT="$2"
+VENDOR="$3"
+PRODUCT="$4"
+DEVICE="$5"
+DEV_CLASS="$6"
+DEV_SUBCLASS="$7"
+DEV_PROTOCOL="$8"
+INTF_CLASS="$9"
+INTF_SUBCLASS="${10}"
+INTF_PROTOCOL="${11}"
+INTF_NUM="${12}"
+
+if [ -z "${TEST_CASE_ID}" -o -z "${COUNT}" -o -z "${VENDOR}" ]; then
+	echo "Usage: $0 <test-case-id> <count> <vendor> [<product> <device> <device-class> <device-subclass> <device-protocol> <interface-class> <interface-subclass> <interface-protocol> <interface-number>]"
+	echo "Note: '*' can be used as wildcard for any field"
+	exit 1
+fi
+
+match()
+{
+	FILE="$1"
+	ID="$2"
+
+	[ ! -f "$FILE" ] && return 1
+	[ "$ID" = "*" -o "$ID" = "" ] && return 0
+	[ $(cat "$FILE") != "$ID" ] && return 1
+	return 0
+}
+
+cur_count=0
+
+for dev in $(find /sys/bus/usb/devices -maxdepth 1); do
+	match "$dev"/idVendor "$VENDOR" || continue
+	match "$dev"/idProduct "$PRODUCT" || continue
+	match "$dev"/bcdDevice "$DEVICE" || continue
+	match "$dev"/bDeviceClass "$DEV_CLASS" || continue
+	match "$dev"/bDeviceSubClass "$DEV_SUBCLASS" || continue
+	match "$dev"/bDeviceProtocol "$DEV_PROTOCOL" || continue
+
+	# Matched device. Now search through interfaces
+	for intf in $(find "$dev"/ -maxdepth 1 -type d); do
+		match "$intf"/bInterfaceClass "$INTF_CLASS" || continue
+		match "$intf"/bInterfaceSubClass "$INTF_SUBCLASS" || continue
+		match "$intf"/bInterfaceProtocol "$INTF_PROTOCOL" || continue
+		match "$intf"/bInterfaceNumber "$INTF_NUM" || continue
+
+		# Matched interface. Add to count if it was probed by driver.
+		[ -d "$intf"/driver ] && cur_count=$((cur_count+1))
+	done
+done
+
+if [ "$cur_count" -eq "$COUNT" ]; then
+	test_report_exit pass
+else
+	test_report_exit fail
+fi