Messages in this thread | | | From | Tim Harvey <> | Date | Tue, 25 Feb 2020 14:25:40 -0800 | Subject | Re: [PATCH] can: mcp251x: convert to half-duplex SPI |
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On Tue, Feb 25, 2020 at 1:43 PM Marc Kleine-Budde <mkl@pengutronix.de> wrote: > > On 2/25/20 7:35 PM, Tim Harvey wrote: > > Some SPI host controllers such as the Cavium Thunder do not support > > full-duplex SPI. Using half-duplex transfers allows the driver to work > > with those host controllers. > > There are several transfers left in the driver, where both rx_buf and > tx_buf are set. How does your host controller driver know which one to > handle? >
Marc,
Your right... there is the mcp251x_hw_rx_frame() call that also uses spi_rx_buf after a synchronous transfer (I didn't see any others). I'll look at this again.
In general is it an ok approach to switch the driver to half-duplex for this issue without the need of complicating things with a module/dt param?
Regards,
Tim
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