lock SPI only when writing #71
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FoamyGuy
approved these changes
Aug 21, 2025
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FunHouse()object, and then trying to do some network activity.Before this fix, the
DotStarobject grabbed theSPIlock forever. This is a problem on Espressif boards, which use a FreeRTOS mutex as the lock. See adafruit/circuitpython#10561 (comment) for details.The fix is only to grab the
SPIlock when actually writing. We could do this withadafruit_bus_device, but we don't need other aspects of that library, and we can save space just by doing the locking in the two places where it's needed.There isn't a reason to test that
self._spi.try_lock()succeeds or fails, since it should always succeed. TheSPIobject is not used by anyone else.Tested on a FunHouse. It fixes the crash described in adafruit/circuitpython#10520. I also tested to make sure the DotStars are still functional.