linux/include
Marcelo Schmitt f58872f45c
spi: Enable controllers to extend the SPI protocol with MOSI idle configuration
The behavior of an SPI controller data output line (SDO or MOSI or COPI
(Controller Output Peripheral Input) for disambiguation) is usually not
specified when the controller is not clocking out data on SCLK edges.
However, there do exist SPI peripherals that require specific MOSI line
state when data is not being clocked out of the controller.

Conventional SPI controllers may set the MOSI line on SCLK edges then bring
it low when no data is going out or leave the line the state of the last
transfer bit. More elaborated controllers are capable to set the MOSI idle
state according to different configurable levels and thus are more suitable
for interfacing with demanding peripherals.

Add SPI mode bits to allow peripherals to request explicit MOSI idle state
when needed.

When supporting a particular MOSI idle configuration, the data output line
state is expected to remain at the configured level when the controller is
not clocking out data. When a device that needs a specific MOSI idle state
is identified, its driver should request the MOSI idle configuration by
setting the proper SPI mode bit.

Acked-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Tested-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Link: https://patch.msgid.link/9802160b5e5baed7f83ee43ac819cb757a19be55.1720810545.git.marcelo.schmitt@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-29 01:19:51 +01:00
..
acpi Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00
asm-generic Kbuild updates for v6.11 2024-07-23 14:32:21 -07:00
clocksource
crypto
drm Merge tag 'drm-intel-next-2024-06-28' of https://gitlab.freedesktop.org/drm/i915/kernel into drm-next 2024-07-10 10:36:47 +02:00
dt-bindings I3C for 6.11 2024-07-27 10:53:06 -07:00
keys
kunit kunit: Introduce KUNIT_ASSERT_MEMEQ and KUNIT_ASSERT_MEMNEQ macros 2024-07-12 10:12:11 -06:00
kvm
linux minmax: simplify and clarify min_t()/max_t() implementation 2024-07-28 13:50:01 -07:00
math-emu
media media: rc: add keymap for MyGica UTV3 remote 2024-06-29 12:20:05 +02:00
memory
misc
net sysctl: treewide: constify the ctl_table argument of proc_handlers 2024-07-24 20:59:29 +02:00
pcmcia
ras mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND 2024-07-12 15:52:22 -07:00
rdma RDMA/core: Introduce "name_assign_type" for an IB device 2024-07-04 07:59:53 +03:00
rv
scsi Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00
soc sound updates for 6.11-rc1 2024-07-19 12:39:34 -07:00
sound sound fixes for 6.11-rc1 2024-07-26 11:01:31 -07:00
target
trace Fixes and minor updates for the timer migration code: 2024-07-27 10:19:55 -07:00
uapi spi: Enable controllers to extend the SPI protocol with MOSI idle configuration 2024-07-29 01:19:51 +01:00
ufs Merge patch series "Basic inline encryption support for ufs-exynos" 2024-07-10 22:33:34 -04:00
vdso Random number generator updates for Linux 6.11-rc1. 2024-07-24 10:29:50 -07:00
video fbdev: mmp: Constify struct mmp_overlay_ops 2024-06-25 14:40:01 +02:00
xen Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00