On 6/6/24 1:51 AM, Nuno Sá wrote: > On Wed, 2024-06-05 at 12:03 -0500, David Lechner wrote: >> On 6/4/24 5:43 PM, Marcelo Schmitt wrote: >>> Implement MOSI idle low and MOSI idle high to better support peripherals >>> that request specific MOSI behavior. >>> >>> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> >>> --- >>> drivers/spi/spi-axi-spi-engine.c | 8 +++++++- >>> 1 file changed, 7 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi- >>> engine.c >>> index 0aa31d745734..549f03069d0e 100644 >>> --- a/drivers/spi/spi-axi-spi-engine.c >>> +++ b/drivers/spi/spi-axi-spi-engine.c >>> @@ -41,6 +41,7 @@ >>> #define SPI_ENGINE_CONFIG_CPHA BIT(0) >>> #define SPI_ENGINE_CONFIG_CPOL BIT(1) >>> #define SPI_ENGINE_CONFIG_3WIRE BIT(2) >>> +#define SPI_ENGINE_CONFIG_SDO_IDLE BIT(3) >>> >>> #define SPI_ENGINE_INST_TRANSFER 0x0 >>> #define SPI_ENGINE_INST_ASSERT 0x1 >>> @@ -132,6 +133,10 @@ static unsigned int spi_engine_get_config(struct >>> spi_device *spi) >>> config |= SPI_ENGINE_CONFIG_CPHA; >>> if (spi->mode & SPI_3WIRE) >>> config |= SPI_ENGINE_CONFIG_3WIRE; >>> + if (spi->mode & SPI_MOSI_IDLE_HIGH) >>> + config |= SPI_ENGINE_CONFIG_SDO_IDLE; >>> + if (spi->mode & SPI_MOSI_IDLE_LOW) >>> + config &= ~SPI_ENGINE_CONFIG_SDO_IDLE; >>> >>> return config; >>> } >>> @@ -645,7 +650,8 @@ static int spi_engine_probe(struct platform_device >>> *pdev) >>> return ret; >>> >>> host->dev.of_node = pdev->dev.of_node; >>> - host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE; >>> + host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE | >>> SPI_MOSI_IDLE_LOW >>> + | SPI_MOSI_IDLE_HIGH; >>> host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); >>> host->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2; >>> host->transfer_one_message = spi_engine_transfer_one_message; >> >> I think we need a version check instead of setting the flags unconditionally >> here since older versions of the AXI SPI Engine won't support this feature. > > Oh, was not aware of that... Then, we definitely need to do that. Marcelo, only > add my r-b tag with the version change in place. > > - Nuno Sá Actually, looking at [1], it looks like this could be a compile-time flag when the HDL is built. If it stays that way, then we would need a way to read that flag from a register instead of using the version. [1]: https://github.com/analogdevicesinc/hdl/pull/1320#issuecomment-2145744521
