spi_nxp_lpspi: Fix extra byte sent issue #92471
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This early exit section is only reached if there is an error. In the case of not supported, the ret variable will be 0 and zassert won't happen. This is because the test was meant to be skipped, not passed or failed, in this case. So add the skip call. Signed-off-by: Declan Snyder <[email protected]>
The interrupt handling was not deterministic before because it relied on "guessing" if the lpspi was a v1 type that was stalling due to design errata. This obviously ended up being wrong in some cases. So we really need to fix this so that it is deterministic, and my idea to do that is to explicitly count how many words we have written to the TX fifo throughout the whole transfer. As a side effect of making the IRQ more deterministic, we can't support the SPI_HOLD_ON_CS flag for v1 LPSPI anymore. It is fundamentally impossible due to the fact that the transfer can only complete in hardware as a result of CS deasserting. If this is absolutely a requirement to support this flag in the future, my recommendation is to update the driver so that it muxes the pin to a gpio before ending the transfer, but that would kind of defeat the point of having a native CS, at least at the end of the xfer. Signed-off-by: Declan Snyder <[email protected]>
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I added hotfix as this is needed to get sensor PRs in that currently are failing on main. This has been tested on the VMU_RT1170 and fixes the icm42688 driver failure. |
bperseghetti
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dleach02
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This is something like, rewrite # 8 of this ISR. I will admit though, that the current IRQ handling is evidentially non-deterministic, so this is needed. I think this should finally nail down these race conditions on the older LPSPI due to that stalling errata. Although, I have said that many times now.
Also as a result of this PR, we can not longer (pretend to?) support the SPI_HOLD_ON_CS flag on LPSPI v1.
Fixes #90614 and maybe some others, pending investigations.