[RFC PATCH 0/6] nvmem: add block device NVMEM provider

[Daniel Golle <daniel@makrotopia.org>]

On embedded devices using an eMMC it is common that one or more (hw/sw)
partitions on the eMMC are used to store MAC addresses and Wi-Fi
calibration EEPROM data.

Implement an NVMEM provider backed by block devices as typically the
NVMEM framework is used to have kernel drivers read and use binary data
from EEPROMs, efuses, flash memory (MTD), ...

In order to be able to reference hardware partitions on an eMMC, add code
to bind each hardware partition to a specific firmware subnode.

This series is meant to open the discussion on how exactly the device tree
schema for block devices and partitions may look like, and even if using
the block layer to back the NVMEM device is at all the way to go -- to me
it seemed to be a good solution because it will be reuable e.g. for NVMe.

Daniel Golle (6):
  mmc: core: set card fwnode_handle
  mmc: block: set fwnode of disk devices
  block: add new genhd flag GENHD_FL_NO_NVMEM
  mtd: blkdevs: set GENHD_FL_NO_NVMEM
  mtd: ubi: block: set GENHD_FL_NO_NVMEM
  block: implement NVMEM provider

 block/Kconfig             |   8 ++
 block/Makefile            |   1 +
 block/blk-nvmem.c         | 187 ++++++++++++++++++++++++++++++++++++++
 block/blk.h               |  13 +++
 block/genhd.c             |   2 +
 block/partitions/core.c   |   2 +
 drivers/mmc/core/block.c  |   8 ++
 drivers/mmc/core/bus.c    |   2 +
 drivers/mtd/mtd_blkdevs.c |   1 +
 drivers/mtd/ubi/block.c   |   2 +-
 include/linux/blkdev.h    |   3 +
 11 files changed, 228 insertions(+), 1 deletion(-)
 create mode 100644 block/blk-nvmem.c

-- 
2.41.0