This commit introduces a timer capture driver for the STM32H7 series
ported from the STM32 F series.
The main changes include:
- A new generic timer capture driver for STM32H7.
- A lower-half driver to integrate with the NuttX capture subsystem.
- Kconfig options to enable and configure capture for various timers.
- Pin definitions for TIM1-4 capture inputs on the nucleo-h743zi.
- An update to `cap_register_multiple` to handle multiple device registration.
- An update to `stm32_bringup` to register the capture drivers.
The current implementation is based on a driver originally for PWM input,
and as such, it calculates duty cycle and frequency. It is also limited
to a single capture channel per timer.
The original implementation's `stm32_cap_init` in
`arch/arm/src/stm32h7/stm32_capture.c` has been modified to accept a
channel number instead of using a hardcoded 0 through
`STM32_CAP_CHANNEL_COUNTER`.
This serves as a foundation for future development of more comprehensive
input capture capabilities on STM32H7 platforms.
Tested by polling and reading `/dev/cap0-4` with
`ioctl(fds[i], CAPIOC_FREQUENCE, freq)` while sending a square wave signal to
appropriate pins and checking frequency.
Also tested by bypassing upper half driver and setting up capture on
TIM4 channels 1-4 as explained in #16762.
Signed-off-by: Côme VINCENT <44554692+comejv@users.noreply.github.com>