2  * LPC32xx SSP interface (SPI mode)
5  * Written-by: Albert ARIBAUD <albert.aribaud@3adev.fr>
7  * SPDX-License-Identifier:     GPL-2.0+
14 #include <spi.h>
39 /* lpc32xx spi slave */
41 	struct spi_slave slave;  member
46 	struct spi_slave *slave)  in to_lpc32xx_spi_slave()  argument
48 	return container_of(slave, struct lpc32xx_spi_slave, slave);  in to_lpc32xx_spi_slave()
69 		pr_err("3-wire mode not supported");  in spi_setup_slave()
74 		pr_err("slave mode not supported\n");  in spi_setup_slave()
89 	lslave->regs = (struct ssp_regs *)SSP0_BASE;  in spi_setup_slave()
92 	 * 8 bit frame, SPI fmt, 500kbps -> clock divider is 26.  in spi_setup_slave()
96 	writel(0x7, &lslave->regs->cr0); /* 8-bit chunks, SPI, 1 clk/bit */  in spi_setup_slave()
97 	writel(26, &lslave->regs->cpsr); /* SSP clock = HCLK/26 = 500kbps */  in spi_setup_slave()
98 	writel(0, &lslave->regs->imsc); /* do not raise any interrupts */  in spi_setup_slave()
99 	writel(0, &lslave->regs->icr); /* clear any pending interrupt */  in spi_setup_slave()
100 	writel(0, &lslave->regs->dmacr); /* do not do DMAs */  in spi_setup_slave()
101 	writel(SSP_CR1_SSP_ENABLE, &lslave->regs->cr1); /* enable SSP0 */  in spi_setup_slave()
102 	return &lslave->slave;  in spi_setup_slave()
105 void spi_free_slave(struct spi_slave *slave)  in spi_free_slave()  argument
107 	struct lpc32xx_spi_slave *lslave = to_lpc32xx_spi_slave(slave);  in spi_free_slave()
113 int spi_claim_bus(struct spi_slave *slave)  in spi_claim_bus()  argument
115 	/* only one bus and slave so far, always available */  in spi_claim_bus()
119 int spi_xfer(struct spi_slave *slave, unsigned int bitlen,  in spi_xfer()  argument
122 	struct lpc32xx_spi_slave *lslave = to_lpc32xx_spi_slave(slave);  in spi_xfer()
130 		int status = readl(&lslave->regs->sr);  in spi_xfer()
132 			writel(((u8 *)dout)[idx_out++], &lslave->regs->data);  in spi_xfer()
134 			((u8 *)din)[idx_in++] = readl(&lslave->regs->data);  in spi_xfer()
136 			return -1;  in spi_xfer()
141 void spi_release_bus(struct spi_slave *slave)  in spi_release_bus()  argument