[yocto] [meta-raspberrypi][PATCH v6 4/4] sdcard_image-rpi.bbclass: support for .dtbo files for dtb overlays

[Herve Jourdain]

Kernel 4.4.6+ on RaspberryPi support .dtbo files for overlays, instead of .dtb.
Add support for both extensions for overlays (".dtb" and ".dtbo")

CAUTION: in IMAGE_CMD_rpi-sdimg, 'TMPDIR' is not set, causing 'STAGING_KERNEL_BUILDDIR' to not be expanded, causing get_dts() to not being able to get the kernel version!
To avoid this problem, the kernel version is added in a new variable outside the scope of IMAGE_CMD_rpi-sdimg, and its value passed to get_dts() and split_overlays()!

Signed-off-by: Herve Jourdain <herve.jourdain at neuf.fr>
---
 classes/sdcard_image-rpi.bbclass | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/classes/sdcard_image-rpi.bbclass b/classes/sdcard_image-rpi.bbclass
index 57cefea..a04204a 100644
--- a/classes/sdcard_image-rpi.bbclass
+++ b/classes/sdcard_image-rpi.bbclass
@@ -75,6 +75,8 @@ IMAGEDATESTAMP = "${@time.strftime('%Y.%m.%d',time.gmtime())}"
 IMAGE_CMD_rpi-sdimg[vardepsexclude] += "IMAGEDATESTAMP"
 IMAGE_CMD_rpi-sdimg[vardepsexclude] += "DATETIME"
 
+RPI_KERNEL_VERSION := "${@get_kernelversion_file('${STAGING_KERNEL_BUILDDIR}')}"
+
 IMAGE_CMD_rpi-sdimg () {
 
 	# Align partitions
@@ -85,7 +87,7 @@ IMAGE_CMD_rpi-sdimg () {
 	echo "Creating filesystem with Boot partition ${BOOT_SPACE_ALIGNED} KiB and RootFS $ROOTFS_SIZE KiB"
 
 	# Check if we are building with device tree support
-	DTS="${@get_dts(d, None)}"
+	DTS="${@get_dts(d, '${RPI_KERNEL_VERSION}')}"
 
 	# Initialize sdcard image file
 	dd if=/dev/zero of=${SDIMG} bs=1024 count=0 seek=${SDIMG_SIZE}
@@ -105,9 +107,9 @@ IMAGE_CMD_rpi-sdimg () {
 	mkfs.vfat -n "${BOOTDD_VOLUME_ID}" -S 512 -C ${WORKDIR}/boot.img $BOOT_BLOCKS
 	mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/bcm2835-bootfiles/* ::/
 	if test -n "${DTS}"; then
-		# Device Tree Overlays are assumed to be suffixed by '-overlay.dtb' string and will be put in a dedicated folder
-		DT_OVERLAYS="${@split_overlays(d, 0)}"
-		DT_ROOT="${@split_overlays(d, 1)}"
+		# Device Tree Overlays are assumed to be suffixed by '-overlay.dtb' (4.1.x) or by '.dtbo' (4.4.9+) string and will be put in a dedicated folder
+		DT_OVERLAYS="${@split_overlays(d, '${RPI_KERNEL_VERSION}', 0)}"
+		DT_ROOT="${@split_overlays(d, '${RPI_KERNEL_VERSION}', 1)}"
 
 		# Copy board device trees to root folder
 		for DTB in ${DT_ROOT}; do
@@ -119,9 +121,10 @@ IMAGE_CMD_rpi-sdimg () {
 		# Copy device tree overlays to dedicated folder
 		mmd -i ${WORKDIR}/boot.img overlays
 		for DTB in ${DT_OVERLAYS}; do
-			DTB_BASE_NAME=`basename ${DTB} .dtb`
+				DTB_EXT=${DTB##*.}
+				DTB_BASE_NAME=`basename ${DTB} ."${DTB_EXT}"`
 
-			mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/${KERNEL_IMAGETYPE}-${DTB_BASE_NAME}.dtb ::overlays/${DTB_BASE_NAME}.dtb
+			mcopy -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/${KERNEL_IMAGETYPE}-${DTB_BASE_NAME}.${DTB_EXT} ::overlays/${DTB_BASE_NAME}.${DTB_EXT}
 		done
 	fi
 	case "${KERNEL_IMAGETYPE}" in
-- 
2.7.4