[v7,00/14] External ECC engines & Macronix support

Hello all,

As I received the last missing ack from Rob for the first halve of the
series (bindings + ECC part) I've applied the beginning of the series
in a branch named spi-mem-ecc on the MTD korg repository, hence now I am
resending only the second halve, including spi-mem and spi changes,
mostly. When that second part will be validated, I will apply it on top
of the spi-mem-ecc branch and set an immutable tag, shared with the spi
tree.

Cheers,
Miquèl

Changes in v7:
* Added a macro to check if the caps are present or not before accessing
  them. This allows for optional caps.
* Dropped the 'no-caps' instance created in v6.
* Reworked a bit all the patches using these caps to have a nice and
  bisectable series, like adding missing static keywords.

Changes in v6:
* Re-include the first patches because a few things have changed in the
  bindings. These are only style changes as Rob asked to group every
  property above or below the description field, which I applied to all
  the binding commits, but without any further update.
* Created a spi-mem capabilities structure. Put that one in the spi-mem
  ops strucure and ensured that all the controllers provided one.
* Created a default "no-caps" empty instance that controller drivers can
  point to by default.
* Dropped the spi_mem_generic_defaults_op() intermediate helper entirely
  (not needed anymore).

Changes in v5:
* Moved a helper in the core as it seems that it will be useful for
  other ECC engines as well (Xiangsheng Hou for Mediatek will need it).
* Changed the parameters of the spi_mem_generic_supports_op() function
  in order to take a structure as input instead of a list of arguments,
  which will be much easier to complement in the future if ever needed.

Changes in v4:
* The first half of the series has been left aside (all the binding
  changes + the external mode in the Macronix driver), now let's focus
  on the pipelined mode.
* Added the ecc_en spi_mem_op structure parameter in a dedicated commit.
* Introduced a new helper for supporting generically the supported ops.
* Used this new helper in the macronix driver.
* By default all the other drivers would refuse a spi_mem_op with ecc_en
  enabled.

Changes in v3:
* Added Mark's R-by.
* Added a commit changing the initialization order between the dirmaps
  and the ECC engine so that the core might now if we are using a
  pipelined engine or not.
* Stopped creating additional dirmaps with ECC if the engine is not a
  pipelined engine.
* Solved the kernel test robot reports. In particular, I added a
  dependency on MTD_NAND_ECC to Macronix SPI controller driver.
* Added a patch to clean the NAND controller yaml file before moving
  some bits to nand-chip.yaml. This addresses the comments made by Rob
  about the useless allOf's.
* Used platform_get_irq_byname_optional() in order to avoid useless
  warnings when there is no IRQ.

Changes in v2:
* Fixed the bindings and added Rob's acks when relevant.
* Added locking in the ECC engine driver.
* Brought more changes in the core in order to bring the ECC information
  into the spi_mem_op structure with the idea of avoiding any races
  between parallel calls on the same engine.
* Reorganized the ECC driver entirely in order to have a per-engine mxic
  structure plus a per-NAND context. This lead to a number of changes
  internally which cannot all be listed.

Changes since the RFC:
* Rebased on top of v5.15-rc1.
* Fixed the dirmap configuration.
* Added the various tags received.
* Fixed the bindings as reported by the robots.
* Fixed the return value of the helper counting bitflips.
* Included a fix from Jaime Liao in the external pattern logic.
* Added the yaml conversion of Macronix SPI controller description.
* Added the yaml conversion of the SPI-NAND description.
* Created a nand-chip.yaml file to share properties between SPI-NAND and
  raw NAND.

Miquel Raynal (14):
  spi: spi-mem: Fix a DTR related check in spi_mem_dtr_supports_op()
  spi: spi-mem: Introduce a capability structure
  spi: spi-mem: Check the controller extra capabilities
  spi: cadence: Provide a capability structure
  spi: mxic: Provide a capability structure
  spi: spi-mem: Kill the spi_mem_dtr_supports_op() helper
  spi: spi-mem: Add an ecc_en parameter to the spi_mem_op structure
  mtd: spinand: Delay a little bit the dirmap creation
  mtd: spinand: Create direct mapping descriptors for ECC operations
  spi: mxic: Fix the transmit path
  spi: mxic: Create a helper to configure the controller before an
    operation
  spi: mxic: Create a helper to ease the start of an operation
  spi: mxic: Add support for direct mapping
  spi: mxic: Add support for pipelined ECC operations

 drivers/mtd/nand/spi/core.c       |  51 ++++-
 drivers/spi/Kconfig               |   2 +-
 drivers/spi/spi-cadence-quadspi.c |  10 +-
 drivers/spi/spi-mem.c             |  32 +--
 drivers/spi/spi-mxic.c            | 340 ++++++++++++++++++++++++------
 include/linux/mtd/spinand.h       |   2 +
 include/linux/spi/spi-mem.h       |  29 ++-
 7 files changed, 366 insertions(+), 100 deletions(-)