diff options
Diffstat (limited to 'drivers/spi/lpc32xx_ssp.c')
-rw-r--r-- | drivers/spi/lpc32xx_ssp.c | 134 |
1 files changed, 0 insertions, 134 deletions
diff --git a/drivers/spi/lpc32xx_ssp.c b/drivers/spi/lpc32xx_ssp.c deleted file mode 100644 index 4b09366317..0000000000 --- a/drivers/spi/lpc32xx_ssp.c +++ /dev/null @@ -1,134 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * LPC32xx SSP interface (SPI mode) - * - * (C) Copyright 2014 DENX Software Engineering GmbH - * Written-by: Albert ARIBAUD <albert.aribaud@3adev.fr> - */ - -#include <common.h> -#include <linux/compat.h> -#include <asm/io.h> -#include <malloc.h> -#include <spi.h> -#include <asm/arch/clk.h> - -/* SSP chip registers */ -struct ssp_regs { - u32 cr0; - u32 cr1; - u32 data; - u32 sr; - u32 cpsr; - u32 imsc; - u32 ris; - u32 mis; - u32 icr; - u32 dmacr; -}; - -/* CR1 register defines */ -#define SSP_CR1_SSP_ENABLE 0x0002 - -/* SR register defines */ -#define SSP_SR_TNF 0x0002 -/* SSP status RX FIFO not empty bit */ -#define SSP_SR_RNE 0x0004 - -/* lpc32xx spi slave */ -struct lpc32xx_spi_slave { - struct spi_slave slave; - struct ssp_regs *regs; -}; - -static inline struct lpc32xx_spi_slave *to_lpc32xx_spi_slave( - struct spi_slave *slave) -{ - return container_of(slave, struct lpc32xx_spi_slave, slave); -} - -/* the following is called in sequence by do_spi_xfer() */ - -struct spi_slave *spi_setup_slave(uint bus, uint cs, uint max_hz, uint mode) -{ - struct lpc32xx_spi_slave *lslave; - - /* we only set up SSP0 for now, so ignore bus */ - - if (mode & SPI_3WIRE) { - pr_err("3-wire mode not supported"); - return NULL; - } - - if (mode & SPI_SLAVE) { - pr_err("slave mode not supported\n"); - return NULL; - } - - if (mode & SPI_PREAMBLE) { - pr_err("preamble byte skipping not supported\n"); - return NULL; - } - - lslave = spi_alloc_slave(struct lpc32xx_spi_slave, bus, cs); - if (!lslave) { - printf("SPI_error: Fail to allocate lpc32xx_spi_slave\n"); - return NULL; - } - - lslave->regs = (struct ssp_regs *)SSP0_BASE; - - /* - * 8 bit frame, SPI fmt, 500kbps -> clock divider is 26. - * Set SCR to 0 and CPSDVSR to 26. - */ - - writel(0x7, &lslave->regs->cr0); /* 8-bit chunks, SPI, 1 clk/bit */ - writel(26, &lslave->regs->cpsr); /* SSP clock = HCLK/26 = 500kbps */ - writel(0, &lslave->regs->imsc); /* do not raise any interrupts */ - writel(0, &lslave->regs->icr); /* clear any pending interrupt */ - writel(0, &lslave->regs->dmacr); /* do not do DMAs */ - writel(SSP_CR1_SSP_ENABLE, &lslave->regs->cr1); /* enable SSP0 */ - return &lslave->slave; -} - -void spi_free_slave(struct spi_slave *slave) -{ - struct lpc32xx_spi_slave *lslave = to_lpc32xx_spi_slave(slave); - - debug("(lpc32xx) spi_free_slave: 0x%08x\n", (u32)lslave); - free(lslave); -} - -int spi_claim_bus(struct spi_slave *slave) -{ - /* only one bus and slave so far, always available */ - return 0; -} - -int spi_xfer(struct spi_slave *slave, unsigned int bitlen, - const void *dout, void *din, unsigned long flags) -{ - struct lpc32xx_spi_slave *lslave = to_lpc32xx_spi_slave(slave); - int bytelen = bitlen >> 3; - int idx_out = 0; - int idx_in = 0; - int start_time; - - start_time = get_timer(0); - while ((idx_out < bytelen) || (idx_in < bytelen)) { - int status = readl(&lslave->regs->sr); - if ((idx_out < bytelen) && (status & SSP_SR_TNF)) - writel(((u8 *)dout)[idx_out++], &lslave->regs->data); - if ((idx_in < bytelen) && (status & SSP_SR_RNE)) - ((u8 *)din)[idx_in++] = readl(&lslave->regs->data); - if (get_timer(start_time) >= CONFIG_LPC32XX_SSP_TIMEOUT) - return -1; - } - return 0; -} - -void spi_release_bus(struct spi_slave *slave) -{ - /* do nothing */ -} |