xmm2usb

#!/bin/sh

die() {
	echo "ERROR ${1}" >&2
	exit 1
}

[ "$(whoami)" = "root" ] || die "must be run as root"

for path in `find /sys/devices/pci0000:00 -name vendor`; do
	path="${path%/vendor}"

	[ -e "${path}/device" ] || continue

	read -r vendor < "${path}/vendor" || continue
	read -r device < "${path}/device" || continue
	[ "${vendor}" = 0x8086 -a "${device}" = 0x7360 ] || continue

	modem_id=${path##*/}
	read -r acpi_path < "${path}/firmware_node/path" || \
		die "Cannot read firmware node path"

	printf "Found XMM7360 modem at %s (%s)\n" "${modem_id}" "${acpi_path}" >&2

	bridge_id="${path%/*}"
	bridge_id="${bridge_id##*/}"

	printf "Parent port is at %s\n" "${bridge_id}" >&2

	modprobe acpi_call || \
		die "Could not load acpi_call module. Is it missing?"

	printf "Disabling PCIe link...\n" >&2
	setpci -s "${bridge_id}" "CAP_EXP+10.w=0052" || \
		die "Could not run setpci"

	printf "%s" "${acpi_path}._RST" > /proc/acpi/call || \
		die "Could not reset PCI"

	echo "OK!"

	exit 0
done

die "Did not find an XMM7360 modem"