Hello, A year ago Bernhard Frauendienst started an effort to bring MTD devices concatenation generic [1]. Today I also need this concatenation to be possible in order to support configurations where two MTD devices are treated like one bigger in order to be able to define partitions across chip boundaries. After having talked with Mark Brown, Boris Brezillon and Rob Herring, the only approach which seems acceptable is to add a property in the partitions nodes to describe which partitions should be concatenated in a virtual device. At first I changed a bit the code logic and style, keeping the logic from the original version. Since the last bindings change, I rewrote almost all the driver, so I took ownership on it, keeping Bernhard in a 'Suggested-by' tag. I would like to add another way to concatenate devices: with module parameters/arguments on the cmdline. This is easily doable in a second time. Thanks, Miquèl [1] https://lwn.net/ml/linux-kernel/20180907173515.19990-1-kernel@xxxxxxxxxxxxxxxxx/ Bernhard Frauendienst (1): mtd: Add get_mtd_device_by_node() helper Miquel Raynal (3): dt-bindings: mtd: Describe MTD partitions concatenation mtd: concat: Fix a comment referring to an unknown symbol mtd: Add driver for concatenating devices .../devicetree/bindings/mtd/partition.txt | 1 + drivers/mtd/Kconfig | 8 + drivers/mtd/Makefile | 1 + drivers/mtd/mtd_virt_concat.c | 240 ++++++++++++++++++ drivers/mtd/mtdconcat.c | 5 +- drivers/mtd/mtdcore.c | 38 +++ include/linux/mtd/mtd.h | 2 + 7 files changed, 291 insertions(+), 4 deletions(-) create mode 100644 drivers/mtd/mtd_virt_concat.c -- 2.20.1
