Since most of the code in i2c_api.c is now relying on STM32 HAL, there
is now a possibility to make a common usage of this code accross families.
The IP version definition is introduced per family, to allow a switch of
functionnalities, especially the frequency management which differs.
BTw, we fix the F0 frequency settings at the same time.
F1 is managed for now as an exception as the HAL API for sequential transmit
/receive is not yet available (coming soon)
As reported during review, this was not understandable as it is.
the get_i2c_obj allows to get a pointer to i2c_s struct from the
handle pointer. This therefore makes a hard-coded assumption
about the struct itself
in case of 2 consecutives calls to HAL_I2C_Master_Sequential_Receive_IT
with the Xfer mode I2C_FIRST_AND_LAST_FRAME, the second trasnfer does
not start at all.
It seems this is because the previous state is maintained as I2C_STATE_MASTER_BUSY_RX
and therefore the START condition will not be generated
With this new implementation, as in slave implementaiton, we use the
interrupts instead of accessing to registers continuously.
This has 2 main advantages:
- this shall improve performances overall and allows for sleep
time in the future
- this also removes some direct registers access from this
layer of code and makes it more generic among families
The timeout values are based on for loops and therefore should depend
on the core frequency and the I2C interface frequency.
This patch introduces this computation and base the timeout on the time
it should take to send a byte over the I2C interface. When sending a
number of bytes, this value can also be used.
In the loops, the timeout should also be decreased before the while
condition so that its value is 0 in case the timeout elapsed and this
can be treated as an error.
With this new implementation, the slave use the Interrupt
to be notified of a request from master, instead of
accessing to registers continuously.
This has 2 main advantages:
- this shall improve performances overall and allows for sleep
time in the future
- this also removes some direct registers access from this
layer of code and makes it more generic among families
With this commit we define I2C irq handlers that can be used by the driver
in sync mode. This also provides a mecanism for enabling and/or disabling
these handlers
Those handlers will be superseded by MBED ones in case of async mode usage.
Sam Grove
bcostm
Martin Kojtal
andreas.larsson
adustm
Laurent MEUNIER
Brian Daniels
javierpedrido
Michel Jaouen