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path: root/drivers/spi/ep93xx_spi.c
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Diffstat (limited to 'drivers/spi/ep93xx_spi.c')
-rw-r--r--drivers/spi/ep93xx_spi.c272
1 files changed, 0 insertions, 272 deletions
diff --git a/drivers/spi/ep93xx_spi.c b/drivers/spi/ep93xx_spi.c
deleted file mode 100644
index cb682dd..0000000
--- a/drivers/spi/ep93xx_spi.c
+++ /dev/null
@@ -1,272 +0,0 @@
-/*
- * SPI Driver for EP93xx
- *
- * Copyright (C) 2013 Sergey Kostanabev <sergey.kostanbaev <at> fairwaves.ru>
- *
- * Inspired form linux kernel driver and atmel uboot driver
- *
- * SPDX-License-Identifier: GPL-2.0+
- */
-
-#include <common.h>
-#include <spi.h>
-#include <malloc.h>
-
-#include <asm/io.h>
-
-#include <asm/arch/ep93xx.h>
-
-#define SSPBASE SPI_BASE
-
-#define SSPCR0 0x0000
-#define SSPCR0_MODE_SHIFT 6
-#define SSPCR0_SCR_SHIFT 8
-#define SSPCR0_SPH BIT(7)
-#define SSPCR0_SPO BIT(6)
-#define SSPCR0_FRF_SPI 0
-#define SSPCR0_DSS_8BIT 7
-
-#define SSPCR1 0x0004
-#define SSPCR1_RIE BIT(0)
-#define SSPCR1_TIE BIT(1)
-#define SSPCR1_RORIE BIT(2)
-#define SSPCR1_LBM BIT(3)
-#define SSPCR1_SSE BIT(4)
-#define SSPCR1_MS BIT(5)
-#define SSPCR1_SOD BIT(6)
-
-#define SSPDR 0x0008
-
-#define SSPSR 0x000c
-#define SSPSR_TFE BIT(0)
-#define SSPSR_TNF BIT(1)
-#define SSPSR_RNE BIT(2)
-#define SSPSR_RFF BIT(3)
-#define SSPSR_BSY BIT(4)
-#define SSPCPSR 0x0010
-
-#define SSPIIR 0x0014
-#define SSPIIR_RIS BIT(0)
-#define SSPIIR_TIS BIT(1)
-#define SSPIIR_RORIS BIT(2)
-#define SSPICR SSPIIR
-
-#define SSPCLOCK 14745600
-#define SSP_MAX_RATE (SSPCLOCK / 2)
-#define SSP_MIN_RATE (SSPCLOCK / (254 * 256))
-
-/* timeout in milliseconds */
-#define SPI_TIMEOUT 5
-/* maximum depth of RX/TX FIFO */
-#define SPI_FIFO_SIZE 8
-
-struct ep93xx_spi_slave {
- struct spi_slave slave;
-
- unsigned sspcr0;
- unsigned sspcpsr;
-};
-
-static inline struct ep93xx_spi_slave *to_ep93xx_spi(struct spi_slave *slave)
-{
- return container_of(slave, struct ep93xx_spi_slave, slave);
-}
-
-void spi_init()
-{
-}
-
-static inline void ep93xx_spi_write_u8(u16 reg, u8 value)
-{
- writel(value, (unsigned int *)(SSPBASE + reg));
-}
-
-static inline u8 ep93xx_spi_read_u8(u16 reg)
-{
- return readl((unsigned int *)(SSPBASE + reg));
-}
-
-static inline void ep93xx_spi_write_u16(u16 reg, u16 value)
-{
- writel(value, (unsigned int *)(SSPBASE + reg));
-}
-
-static inline u16 ep93xx_spi_read_u16(u16 reg)
-{
- return (u16)readl((unsigned int *)(SSPBASE + reg));
-}
-
-static int ep93xx_spi_init_hw(unsigned int rate, unsigned int mode,
- struct ep93xx_spi_slave *slave)
-{
- unsigned cpsr, scr;
-
- if (rate > SSP_MAX_RATE)
- rate = SSP_MAX_RATE;
-
- if (rate < SSP_MIN_RATE)
- return -1;
-
- /* Calculate divisors so that we can get speed according the
- * following formula:
- * rate = spi_clock_rate / (cpsr * (1 + scr))
- *
- * cpsr must be even number and starts from 2, scr can be any number
- * between 0 and 255.
- */
- for (cpsr = 2; cpsr <= 254; cpsr += 2) {
- for (scr = 0; scr <= 255; scr++) {
- if ((SSPCLOCK / (cpsr * (scr + 1))) <= rate) {
- /* Set CHPA and CPOL, SPI format and 8bit */
- unsigned sspcr0 = (scr << SSPCR0_SCR_SHIFT) |
- SSPCR0_FRF_SPI | SSPCR0_DSS_8BIT;
- if (mode & SPI_CPHA)
- sspcr0 |= SSPCR0_SPH;
- if (mode & SPI_CPOL)
- sspcr0 |= SSPCR0_SPO;
-
- slave->sspcr0 = sspcr0;
- slave->sspcpsr = cpsr;
- return 0;
- }
- }
- }
-
- return -1;
-}
-
-void spi_set_speed(struct spi_slave *slave, unsigned int hz)
-{
- struct ep93xx_spi_slave *as = to_ep93xx_spi(slave);
-
- unsigned int mode = 0;
- if (as->sspcr0 & SSPCR0_SPH)
- mode |= SPI_CPHA;
- if (as->sspcr0 & SSPCR0_SPO)
- mode |= SPI_CPOL;
-
- ep93xx_spi_init_hw(hz, mode, as);
-}
-
-struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
- unsigned int max_hz, unsigned int mode)
-{
- struct ep93xx_spi_slave *as;
-
- if (!spi_cs_is_valid(bus, cs))
- return NULL;
-
- as = spi_alloc_slave(struct ep93xx_spi_slave, bus, cs);
- if (!as)
- return NULL;
-
- if (ep93xx_spi_init_hw(max_hz, mode, as)) {
- free(as);
- return NULL;
- }
-
- return &as->slave;
-}
-
-void spi_free_slave(struct spi_slave *slave)
-{
- struct ep93xx_spi_slave *as = to_ep93xx_spi(slave);
-
- free(as);
-}
-
-int spi_claim_bus(struct spi_slave *slave)
-{
- struct ep93xx_spi_slave *as = to_ep93xx_spi(slave);
-
- /* Enable the SPI hardware */
- ep93xx_spi_write_u8(SSPCR1, SSPCR1_SSE);
-
-
- ep93xx_spi_write_u8(SSPCPSR, as->sspcpsr);
- ep93xx_spi_write_u16(SSPCR0, as->sspcr0);
-
- debug("Select CS:%d SSPCPSR=%02x SSPCR0=%04x\n",
- slave->cs, as->sspcpsr, as->sspcr0);
- return 0;
-}
-
-void spi_release_bus(struct spi_slave *slave)
-{
- /* Disable the SPI hardware */
- ep93xx_spi_write_u8(SSPCR1, 0);
-}
-
-int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
- const void *dout, void *din, unsigned long flags)
-{
- unsigned int len_tx;
- unsigned int len_rx;
- unsigned int len;
- u32 status;
- const u8 *txp = dout;
- u8 *rxp = din;
- u8 value;
-
- debug("spi_xfer: slave %u:%u dout %p din %p bitlen %u\n",
- slave->bus, slave->cs, (uint *)dout, (uint *)din, bitlen);
-
-
- if (bitlen == 0)
- /* Finish any previously submitted transfers */
- goto out;
-
- if (bitlen % 8) {
- /* Errors always terminate an ongoing transfer */
- flags |= SPI_XFER_END;
- goto out;
- }
-
- len = bitlen / 8;
-
-
- if (flags & SPI_XFER_BEGIN) {
- /* Empty RX FIFO */
- while ((ep93xx_spi_read_u8(SSPSR) & SSPSR_RNE))
- ep93xx_spi_read_u8(SSPDR);
-
- spi_cs_activate(slave);
- }
-
- for (len_tx = 0, len_rx = 0; len_rx < len; ) {
- status = ep93xx_spi_read_u8(SSPSR);
-
- if ((len_tx < len) && (status & SSPSR_TNF)) {
- if (txp)
- value = *txp++;
- else
- value = 0xff;
-
- ep93xx_spi_write_u8(SSPDR, value);
- len_tx++;
- }
-
- if (status & SSPSR_RNE) {
- value = ep93xx_spi_read_u8(SSPDR);
-
- if (rxp)
- *rxp++ = value;
- len_rx++;
- }
- }
-
-out:
- if (flags & SPI_XFER_END) {
- /*
- * Wait until the transfer is completely done before
- * we deactivate CS.
- */
- do {
- status = ep93xx_spi_read_u8(SSPSR);
- } while (status & SSPSR_BSY);
-
- spi_cs_deactivate(slave);
- }
-
- return 0;
-}