Upcoming memory protection features will be placing some additional
constraints on kernel objects:
- They need to reside in memory owned by the kernel and not the
application
- Certain kernel object validation schemes will require some run-time
initialization of all kernel objects before they can be used.
Per Ben these initializer macros were never intended to be public. It is
not forbidden to use them, but doing so requires care: the memory being
initialized must reside in kernel space, and extra runtime
initialization steps may need to be peformed before they are fully
usable as kernel objects. In particular, kernel subsystems or drivers
whose objects are already in kernel memory may still need to use these
macros if they define kernel objects as members of a larger data
structure.
It is intended that application developers instead use the
K_<object>_DEFINE macros, which will automatically put the object in the
right memory and add them to a section which can be iterated over at
boot to complete initiailization.
There was no K_WORK_DEFINE() macro for creating struct k_work objects,
this is now added.
k_poll_event and k_poll_signal are intended to be instatiated from
application memory and have not been changed.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Instead of NULL terminated buffer arrays, let's add a parameter for each
that tells the number of spi_buf in it.
It adds a little bit more complexity in driver's side (spi_context.h)
but not on user side (bufer one has to take care of providing the NULL
pointer at the end of the array, now he requires to give the count).
This will saves a significant amount of bytes in more complex setup than
the current dumb spi driver sample.
Fix and Use size_t everywhere (spi_context.h was using u32_t).
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
If CS is controlled over GPIO, it will be possible to keep the slave up
and running (though no transaction will be going on) using this
configuration bit.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
All is done through the generic spi_context driver's API as it will be
generic to all SPI drivers.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
All SPI drivers have this same way to handle synchronous call, thus
let's generalize it in struct spi_context, with a relevant API and apply
the change into SPI DW driver.
spi_context API will prove to be useful once asynchronous call will be
handled as well, through the same completion functions used now only for
synchronous call. It will be transparent for the driver.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Let's improve common SPI driver context by adding a lock and generic
function to get/release it.
It's statically initialized to save a bit of ROM.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Introducing as well a generic driver helper for CS gpio control and
buffer management.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
