Re: [PATCH v2] spi: bcm63xx: fix premature CS deassertion on RX-only transactions

Mark Brown
2025-11-16T21:45:05Z

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On Mon, Nov 17, 2025 at 01:08:35AM +1100, Hang Zhou wrote:

> Fix this by writing 0xff dummy bytes into the TX FIFO for RX-only
> segments so that the number of bytes written to the FIFO matches the
> total message length seen by the controller.

Why 0xff? The core's _MUST_TX handling writes 0x00 which feels a bit
more natural. Given that this is PIO rather than DMA the memset_toio()
is going to be better than using the core (which is more for DMA).

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