drivers/spi/soft_spi_legacy.c

8  * SPDX-License-Identifier:	GPL-2.0+
12 #include <spi.h>
16 /*-----------------------------------------------------------------------
40 /*-----------------------------------------------------------------------
59 	ss->mode = mode;  in spi_setup_slave()
63 	return &ss->slave;  in spi_setup_slave()
81 	 * Make sure the SPI clock is in idle state as defined for  in spi_claim_bus()
84 	if (ss->mode & SPI_CPOL)  in spi_claim_bus()
97 /*-----------------------------------------------------------------------
98  * SPI transfer
100  * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
101  * "bitlen" bits in the SPI MISO port.  That's just the way SPI works.
120 	int		cpol = ss->mode & SPI_CPOL;  in spi_xfer()  local
121 	int		cpha = ss->mode & SPI_CPHA;  in spi_xfer()
125 		slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);  in spi_xfer()
147 			SPI_SCL(!cpol);  in spi_xfer()
151 			SPI_SCL(!cpol);  in spi_xfer()
153 			SPI_SCL(cpol);  in spi_xfer()
159 			SPI_SCL(cpol);  in spi_xfer()
163 	 * bits over to left-justify them.  Then store the last byte  in spi_xfer()
168 			tmpdin <<= 8 - (bitlen % 8);  in spi_xfer()