This allows us to re-use SPIDevice from SPIDeviceDriver (the
to-become-SPIDeviceProperties) while the drivers are
converted. We create a fake device by calling the temporary
SPIDeviceManager::get_device() method passing the descriptor. The
transfer and assert logic is still using the old code.
Now we can interoperate SPIDeviceDriver with the ones based in
SPIDevice since they are going to use the same semaphore and bus.
The way this code is structured is a little bit different from the
SPIDriver implementation:
- We only open the bus once, no matter how many devices we have in it
- There's a single transfer() method which uses half-duplex mode
instead of full duplex. The reason is that for all cases in the
codebase we are using half-duplex transfers using the full-duplex
API, i.e. a single SPI msg with both tx and rx buffers. This is
cumbersome because the buffers need to be of the same size and the
receive buffer using an offset of the same length as the actux data
being written. This means the high level APIs need to copy buffers
around.
If later we have uses for a real full duplex case it's just a matter
of adding another transfer_fullduplex() method or something like
this.
- The methods are implemented in the SPIDevice class instead of having
proxy methods to SPIDeviceManager as is the case of SPIDriver
Also from now on we refer to the SPIDriver objects as "descriptors"
because they have the parameters of each device in the
SPIDeviceManager::devices[] table. When SPIDeviceDriver is completely
replaced we can rename them to SPIDeviceProperties.
Save in the manager the number of devices so it can be used in other
places like the SPIDevice implementation. This is a temporary storage
while we migrate to SPIDevice.
While at it use protected rather than private.
A string name allows to more easily expand the table: the board is
responsible for the name and doesn't have to declare it as a enum or
define. It's also easier to add 2 sensors of the same type.
This was previously used to allow to save a state in a SPIDriver so we
could synchronize the initialization of AP_Compass and
AP_InertialSensor.
It was only used by MPU9250 and is not used anymore since the move to
AuxiliaryBus initialization and it's not used anymore since c3dae6f
("AP_InertialSensor: MPU9250: Remove methods not used anymore")
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
Allowing to change the SPI device state allows us to save the
information whether the device was already initialized and avoid 2
separate drivers to initialize it.
Add support for /dev/spidev<bus>.<cs> in-kernel SPI CS handling, and convert
existing SPI devices over.
* Add a new member _subdev to the LinuxSPIDeviceDriver class, and initialiser
in LinuxSPIDevice constructor. Use subdev 0 for GPIO-managed CS
* Extend the _cs_pin to signed 16 bits and define SPI_CS_KERNEL (-1) for
kernel-managed CS
* Move to per-device file descriptors (required for in-kernel CS)
* Extend spidev filenames to include bus and subdevice numbers, possibly
longer than 1 digit each
* Allow support for platforms enumerating /dev/spidevNNN from non-zero bases
* Convert existing users over to the new API
Signed-off-by: John Williams <john@whelanwilliams.net>
This adds a check for trying to assert two CS pins on the same bus
at the same time. The change involves moving the _device handles into the
DeviceManager class, and accessing via static methods.
This also moves the semaphore to be per-bus rather than per-device,
which fixes the problem with bad MS5611 transfers.
Pair-Programmed-With: Victor, Sid, Anuj and Philip
Lucas De Marchi
mirkix
Gustavo Jose de Sousa
John Williams
Staroselskii Georgii
Andrew Tridgell
Mikhail Avkhimenia
Víctor Mayoral Vilches