[v2,0/4] spi: Fix DMA bugs in (not only) spi-s3c64xx

v2:
- Drop merged patch adding new test to spi-loopback-test
- Fix compiler warning in !HAS_DMA builds
- Add support to split transfers to core

This series fixes some bugs I found while running spi-loopback-test with
spi-s3c64xx.  The first problem (which I actually noticed while trying to fix
the second problem with transfers >64KiB) seems to be a generic issue which
affects several drivers so I fixed it in the core.

The series has been tested on ARTPEC-8, which has a version of the IP similar
to Exynos 7 and with 64 byte FIFOs (compatible with "tesla,fsd-spi").

Cc: alim.akhtar@samsung.com
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org

Vincent Whitchurch (4):
  spi: Save current RX and TX DMA devices
  spi: Fix cache corruption due to DMA/PIO overlap
  spi: Split transfers larger than max size
  spi: s3c64xx: Fix large transfers with DMA

 drivers/spi/spi-s3c64xx.c |   9 +++
 drivers/spi/spi.c         | 137 ++++++++++++++++++++++++++++----------
 include/linux/spi/spi.h   |   4 ++
 3 files changed, 114 insertions(+), 36 deletions(-)

On Tue, 27 Sep 2022 13:21:13 +0200, Vincent Whitchurch wrote:
> v2:
> - Drop merged patch adding new test to spi-loopback-test
> - Fix compiler warning in !HAS_DMA builds
> - Add support to split transfers to core
> 
> This series fixes some bugs I found while running spi-loopback-test with
> spi-s3c64xx.  The first problem (which I actually noticed while trying to fix
> the second problem with transfers >64KiB) seems to be a generic issue which
> affects several drivers so I fixed it in the core.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/4] spi: Save current RX and TX DMA devices
      commit: f25723dcef4a38f6a39e17afeabd1adf6402230e
[2/4] spi: Fix cache corruption due to DMA/PIO overlap
      commit: 0c17ba73c08ff2690c1eff8df374b6709eed55ce
[3/4] spi: Split transfers larger than max size
      commit: 8d699ff95534747e394e0830399b8d5dcf03e738
[4/4] spi: s3c64xx: Fix large transfers with DMA
      commit: 1224e29572f655facfcd850cf0f0a4784f36a903

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark