8  * SPDX-License-Identifier:	GPL-2.0+
12 #include <spi.h>
16 /*-----------------------------------------------------------------------
27 	struct spi_slave slave;  member
31 static inline struct soft_spi_slave *to_soft_spi(struct spi_slave *slave)  in to_soft_spi()  argument
33 	return container_of(slave, struct soft_spi_slave, slave);  in to_soft_spi()
40 /*-----------------------------------------------------------------------
59 	ss->mode = mode;  in spi_setup_slave()
63 	return &ss->slave;  in spi_setup_slave()
66 void spi_free_slave(struct spi_slave *slave)  in spi_free_slave()  argument
68 	struct soft_spi_slave *ss = to_soft_spi(slave);  in spi_free_slave()
73 int spi_claim_bus(struct spi_slave *slave)  in spi_claim_bus()  argument
78 	struct soft_spi_slave *ss = to_soft_spi(slave);  in spi_claim_bus()
81 	 * Make sure the SPI clock is in idle state as defined for  in spi_claim_bus()
82 	 * this slave.  in spi_claim_bus()
84 	if (ss->mode & SPI_CPOL)  in spi_claim_bus()
92 void spi_release_bus(struct spi_slave *slave)  in spi_release_bus()  argument
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.
109 int  spi_xfer(struct spi_slave *slave, unsigned int bitlen,  in spi_xfer()  argument
115 	struct soft_spi_slave *ss = to_soft_spi(slave);  in spi_xfer()
120 	int		cpol = ss->mode & SPI_CPOL;  in spi_xfer()
121 	int		cpha = ss->mode & SPI_CPHA;  in spi_xfer()
124 	PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",  in spi_xfer()
125 		slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);  in spi_xfer()
128 		spi_cs_activate(slave);  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()
173 		spi_cs_deactivate(slave);  in spi_xfer()