meta-agl-bsp: enable HCI UART for i.MX8MQ EVK

Changes:
- Remove explicit "not set" options in btusb.cfg kernel configuration
  fragment to avoid over-riding BSP configuration.
- Add helper script and systemd unit to detect HCI UART device on
  i.MX8MQ EVK and EVKB and run hciattach as necessary.  While logic
  has been added for the QCA6174 on the i.MX8MQ EVK, note that it has
  not been tested due to lack of hardware availability to test.

Bug-AGL: SPEC-3545, SPEC-3681

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: Iae3a58ccfbdb31698ae012ab7d03c9259ac83013
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/25842
Tested-by: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-build: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-boot-test: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>

3 files changed, 87 insertions, 0 deletions

diff --git a/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.service b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.service
new file mode 100644
index 000000000..f8eda0cba
--- /dev/null
+++ b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.service
@@ -0,0 +1,9 @@
+[Unit]
+Description=Bluetooth HCI UART support
+Requires=dev-ttymxc2.device
+After=dev-ttymxc2.device
+Before=bluetooth.service
+
+[Service]
+Type=forking
+ExecStart=/usr/sbin/hci-uart-helper.sh
diff --git a/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.sh b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.sh
new file mode 100644
index 000000000..e1aa31c06
--- /dev/null
+++ b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/files/hci-uart-helper.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+#
+# Script to attach HCI UART devices on i.MX8MQ EVK/EVKB
+#
+# NOTE:
+# For the most part errors are ignored and the script returns
+# 0/success so BlueZ will still be started if the script is somehow
+# run on a board without the expected hardware.  However, if the
+# various probing succeeds and hciattach is run, the script returns
+# the resulting exit code if hciattach fails.
+
+COMPAT=/sys/firmware/devicetree/base/compatible
+HCITTY=/dev/ttymxc2
+PCIDEV=/sys/bus/pci/devices/0000:01:00.0
+
+if [ ! \( -f "$COMPAT" -a -c "$HCITTY" \) ]; then
+    exit 0
+fi
+
+found=false
+for c in `cat $COMPAT | tr '\0' ' '`; do
+    echo "c = $c"
+    if echo $c | grep -q '^fsl,imx8mq-evk$'; then
+        found=true
+        break
+    fi
+done
+if ! $found; then
+    echo "i.MX8MQ EVK not found!"
+    exit 0
+fi
+
+if [ -f "$PCIDEV/vendor" -a -f "$PCIDEV/device" ]; then
+    vendor=`cat $PCIDEV/vendor`
+    device=`cat $PCIDEV/device`
+fi
+
+rc=0
+if [ "$vendor" = "0x14e4" -a "$device" = "0x43ec" ]; then
+    # Broadcom 5436 on EVKB
+    hciattach $HCITTY bcm43xx
+    rc=$?
+elif [ "$vendor" = "0x168c" -a "$device" = "0x003e" ]; then
+    # Qualcomm (nee Atheros) 6174 on EVK
+    hciattach $HCITTY qualcomm
+    rc=$?
+fi
+exit $rc
diff --git a/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/hci-uart-helper_1.0.bb b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/hci-uart-helper_1.0.bb
new file mode 100644
index 000000000..e497a4a21
--- /dev/null
+++ b/meta-agl-bsp/meta-freescale-layer/recipes-connectivity/hci-uart-helper/hci-uart-helper_1.0.bb
@@ -0,0 +1,30 @@
+SUMMARY     = "Helper for enabling UART connected HCI Bluetooth devices"
+LICENSE     = "MIT"
+LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/MIT;md5=0835ade698e0bcf8506ecda2f7b4f302"
+
+inherit systemd allarch
+
+SRC_URI = "file://hci-uart-helper.service \
+           file://hci-uart-helper.sh \
+"
+
+COMPATIBLE_MACHINE = "imx8mqevk"
+
+do_configure[noexec] = "1"
+do_compile[noexec] = "1"
+
+do_install() {
+    # Install helper script
+    install -d ${D}${sbindir}
+    install -m 0755 ${WORKDIR}/hci-uart-helper.sh ${D}${sbindir}/
+
+    # Install systemd unit
+    install -d ${D}${systemd_system_unitdir}/
+    install -m 0644 ${WORKDIR}/hci-uart-helper.service ${D}${systemd_system_unitdir}/
+    install -d ${D}${systemd_system_unitdir}/bluetooth.service.wants
+    ln -s ../hci-uart-helper.service ${D}${systemd_system_unitdir}/bluetooth.service.wants/
+}
+
+FILES_${PN} += "${systemd_system_unitdir}"
+
+RDEPENDS_${PN} += "bluez5"