From 77937846402f011c4c49a97027606902acea7a12 Mon Sep 17 00:00:00 2001 From: Martin Hierholzer Date: Sat, 25 Sep 2021 11:52:31 +0200 Subject: spicmds: Allow inversion of CS pin for SPI busses Signed-off-by: Martin Hierholzer Signed-off-by: Kevin O'Connor --- src/spicmds.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) (limited to 'src') diff --git a/src/spicmds.c b/src/spicmds.c index 8bdefbbf..2c3f3ed6 100644 --- a/src/spicmds.c +++ b/src/spicmds.c @@ -23,17 +23,18 @@ struct spidev_s { }; enum { - SF_HAVE_PIN = 1, SF_SOFTWARE = 2, SF_HARDWARE = 4, + SF_HAVE_PIN = 1, SF_SOFTWARE = 2, SF_HARDWARE = 4, SF_CS_ACTIVE_HIGH = 8 }; void command_config_spi(uint32_t *args) { struct spidev_s *spi = oid_alloc(args[0], command_config_spi, sizeof(*spi)); - spi->pin = gpio_out_setup(args[1], 1); - spi->flags |= SF_HAVE_PIN; + uint_fast8_t cs_active_high = args[2]; + spi->pin = gpio_out_setup(args[1], !cs_active_high); + spi->flags |= SF_HAVE_PIN | (cs_active_high ? SF_CS_ACTIVE_HIGH : 0); } -DECL_COMMAND(command_config_spi, "config_spi oid=%c pin=%u"); +DECL_COMMAND(command_config_spi, "config_spi oid=%c pin=%u cs_active_high=%c"); void command_config_spi_without_cs(uint32_t *args) @@ -86,25 +87,26 @@ void spidev_transfer(struct spidev_s *spi, uint8_t receive_data , uint8_t data_len, uint8_t *data) { - if (!(spi->flags & (SF_SOFTWARE|SF_HARDWARE))) + uint_fast8_t flags = spi->flags; + if (!(flags & (SF_SOFTWARE|SF_HARDWARE))) // Not yet initialized return; - if (CONFIG_HAVE_GPIO_BITBANGING && spi->flags & SF_SOFTWARE) + if (CONFIG_HAVE_GPIO_BITBANGING && flags & SF_SOFTWARE) spi_software_prepare(spi->spi_software); else spi_prepare(spi->spi_config); - if (spi->flags & SF_HAVE_PIN) - gpio_out_write(spi->pin, 0); + if (flags & SF_HAVE_PIN) + gpio_out_write(spi->pin, !!(flags & SF_CS_ACTIVE_HIGH)); - if (CONFIG_HAVE_GPIO_BITBANGING && spi->flags & SF_SOFTWARE) + if (CONFIG_HAVE_GPIO_BITBANGING && flags & SF_SOFTWARE) spi_software_transfer(spi->spi_software, receive_data, data_len, data); else spi_transfer(spi->spi_config, receive_data, data_len, data); - if (spi->flags & SF_HAVE_PIN) - gpio_out_write(spi->pin, 1); + if (flags & SF_HAVE_PIN) + gpio_out_write(spi->pin, !(flags & SF_CS_ACTIVE_HIGH)); } void @@ -163,7 +165,7 @@ spidev_shutdown(void) struct spidev_s *spi; foreach_oid(oid, spi, command_config_spi) { if (spi->flags & SF_HAVE_PIN) - gpio_out_write(spi->pin, 1); + gpio_out_write(spi->pin, !(spi->flags & SF_CS_ACTIVE_HIGH)); } // Send shutdown messages -- cgit v1.2.3-70-g09d2