[PATCH 0/2] Add multi mode support for omap-mcspi

From: Louis Chauvet
Date: Tue Feb 06 2024 - 05:01:24 EST


This series add the support for the omap-mcspi multi mode. It allow
sending SPI message with a shorter delay between CS and the message.

One drawback of the multi-mode is that the CS is raised between each word,
so it can only be used with messages containing 1 word transfers and
asking for cs_change. Few devices, like FPGAs, may easly workaround this
limitation.

The first patch removes the current implementation, which is working, but
don't respect what is asked in the spi transfer (The CS is raised by the
hardware regardless of cs_change state). No drivers or board file use this
implementation upstream.

The second patch adds the implementation of the multi-mode, which respects
what is asked in the SPI message.

Signed-off-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>
---
Louis Chauvet (2):
Revert "spi: spi-omap2-mcspi.c: Toggle CS after each word"
spi: omap2-mcspi: Add support for MULTI-mode

drivers/spi/spi-omap2-mcspi.c | 72 +++++++++++++++++++--------
include/linux/platform_data/spi-omap2-mcspi.h | 3 --
2 files changed, 51 insertions(+), 24 deletions(-)
---
base-commit: 41bccc98fb7931d63d03f326a746ac4d429c1dd3
change-id: 20240126-spi-omap2-mcspi-multi-mode-e62f68b78ad3

Best regards,
--
Louis Chauvet <louis.chauvet@xxxxxxxxxxx>