spi: add support SuperH SPI module

SH7757 has SPI module. This patch supports it.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
This commit is contained in:
Yoshihiro Shimoda 2011-01-31 16:50:43 +09:00 committed by Nobuhiro Iwamatsu
parent 68260aab93
commit 6639562e6a
4 changed files with 346 additions and 0 deletions

5
README
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@ -1660,6 +1660,11 @@ The following options need to be configured:
SPI EEPROM, also an instance works with Crystal A/D and
D/As on the SACSng board)
CONFIG_SH_SPI
Enables the driver for SPI controller on SuperH. Currently
only SH7757 is supported.
CONFIG_SPI_X
Enables extended (16-bit) SPI EEPROM addressing.

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@ -37,6 +37,7 @@ COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o
COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o
COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o
COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o
COBJS-$(CONFIG_SH_SPI) += sh_spi.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)

261
drivers/spi/sh_spi.c Normal file
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@ -0,0 +1,261 @@
/*
* SH SPI driver
*
* Copyright (C) 2011 Renesas Solutions Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <common.h>
#include <malloc.h>
#include <spi.h>
#include <asm/io.h>
#include "sh_spi.h"
static void sh_spi_write(unsigned long data, unsigned long *reg)
{
writel(data, reg);
}
static unsigned long sh_spi_read(unsigned long *reg)
{
return readl(reg);
}
static void sh_spi_set_bit(unsigned long val, unsigned long *reg)
{
unsigned long tmp;
tmp = sh_spi_read(reg);
tmp |= val;
sh_spi_write(tmp, reg);
}
static void sh_spi_clear_bit(unsigned long val, unsigned long *reg)
{
unsigned long tmp;
tmp = sh_spi_read(reg);
tmp &= ~val;
sh_spi_write(tmp, reg);
}
static void clear_fifo(struct sh_spi *ss)
{
sh_spi_set_bit(SH_SPI_RSTF, &ss->regs->cr2);
sh_spi_clear_bit(SH_SPI_RSTF, &ss->regs->cr2);
}
static int recvbuf_wait(struct sh_spi *ss)
{
while (sh_spi_read(&ss->regs->cr1) & SH_SPI_RBE) {
if (ctrlc())
return 1;
udelay(10);
}
return 0;
}
static int write_fifo_empty_wait(struct sh_spi *ss)
{
while (!(sh_spi_read(&ss->regs->cr1) & SH_SPI_TBE)) {
if (ctrlc())
return 1;
udelay(10);
}
return 0;
}
void spi_init(void)
{
}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct sh_spi *ss;
if (!spi_cs_is_valid(bus, cs))
return NULL;
ss = malloc(sizeof(struct spi_slave));
if (!ss)
return NULL;
ss->slave.bus = bus;
ss->slave.cs = cs;
ss->regs = (struct sh_spi_regs *)CONFIG_SH_SPI_BASE;
/* SPI sycle stop */
sh_spi_write(0xfe, &ss->regs->cr1);
/* CR1 init */
sh_spi_write(0x00, &ss->regs->cr1);
/* CR3 init */
sh_spi_write(0x00, &ss->regs->cr3);
clear_fifo(ss);
/* 1/8 clock */
sh_spi_write(sh_spi_read(&ss->regs->cr2) | 0x07, &ss->regs->cr2);
udelay(10);
return &ss->slave;
}
void spi_free_slave(struct spi_slave *slave)
{
struct sh_spi *spi = to_sh_spi(slave);
free(spi);
}
int spi_claim_bus(struct spi_slave *slave)
{
return 0;
}
void spi_release_bus(struct spi_slave *slave)
{
struct sh_spi *ss = to_sh_spi(slave);
sh_spi_write(sh_spi_read(&ss->regs->cr1) &
~(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD), &ss->regs->cr1);
}
static int sh_spi_send(struct sh_spi *ss, const unsigned char *tx_data,
unsigned int len, unsigned long flags)
{
int i, cur_len, ret = 0;
int remain = (int)len;
unsigned long tmp;
if (len >= SH_SPI_FIFO_SIZE)
sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
while (remain > 0) {
cur_len = (remain < SH_SPI_FIFO_SIZE) ?
remain : SH_SPI_FIFO_SIZE;
for (i = 0; i < cur_len &&
!(sh_spi_read(&ss->regs->cr4) & SH_SPI_WPABRT) &&
!(sh_spi_read(&ss->regs->cr1) & SH_SPI_TBF);
i++)
sh_spi_write(tx_data[i], &ss->regs->tbr_rbr);
cur_len = i;
if (sh_spi_read(&ss->regs->cr4) & SH_SPI_WPABRT) {
/* Abort the transaction */
flags |= SPI_XFER_END;
sh_spi_set_bit(SH_SPI_WPABRT, &ss->regs->cr4);
ret = 1;
break;
}
remain -= cur_len;
tx_data += cur_len;
if (remain > 0)
write_fifo_empty_wait(ss);
}
if (flags & SPI_XFER_END) {
tmp = sh_spi_read(&ss->regs->cr1);
tmp = tmp & ~(SH_SPI_SSD | SH_SPI_SSDB);
sh_spi_write(tmp, &ss->regs->cr1);
sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
udelay(100);
write_fifo_empty_wait(ss);
}
return ret;
}
static int sh_spi_receive(struct sh_spi *ss, unsigned char *rx_data,
unsigned int len, unsigned long flags)
{
int i;
unsigned long tmp;
if (len > SH_SPI_MAX_BYTE)
sh_spi_write(SH_SPI_MAX_BYTE, &ss->regs->cr3);
else
sh_spi_write(len, &ss->regs->cr3);
tmp = sh_spi_read(&ss->regs->cr1);
tmp = tmp & ~(SH_SPI_SSD | SH_SPI_SSDB);
sh_spi_write(tmp, &ss->regs->cr1);
sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
for (i = 0; i < len; i++) {
if (recvbuf_wait(ss))
return 0;
rx_data[i] = (unsigned char)sh_spi_read(&ss->regs->tbr_rbr);
}
sh_spi_write(0, &ss->regs->cr3);
return 0;
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
struct sh_spi *ss = to_sh_spi(slave);
const unsigned char *tx_data = dout;
unsigned char *rx_data = din;
unsigned int len = bitlen / 8;
int ret = 0;
if (flags & SPI_XFER_BEGIN)
sh_spi_write(sh_spi_read(&ss->regs->cr1) & ~SH_SPI_SSA,
&ss->regs->cr1);
if (tx_data)
ret = sh_spi_send(ss, tx_data, len, flags);
if (ret == 0 && rx_data)
ret = sh_spi_receive(ss, rx_data, len, flags);
if (flags & SPI_XFER_END) {
sh_spi_set_bit(SH_SPI_SSD, &ss->regs->cr1);
udelay(100);
sh_spi_clear_bit(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD,
&ss->regs->cr1);
clear_fifo(ss);
}
return ret;
}
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
/* This driver supports "bus = 0" and "cs = 0" only. */
if (!bus && !cs)
return 1;
else
return 0;
}
void spi_cs_activate(struct spi_slave *slave)
{
}
void spi_cs_deactivate(struct spi_slave *slave)
{
}

79
drivers/spi/sh_spi.h Normal file
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@ -0,0 +1,79 @@
/*
* SH SPI driver
*
* Copyright (C) 2011 Renesas Solutions Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifndef __SH_SPI_H__
#define __SH_SPI_H__
#include <spi.h>
struct sh_spi_regs {
unsigned long tbr_rbr;
unsigned long resv1;
unsigned long cr1;
unsigned long resv2;
unsigned long cr2;
unsigned long resv3;
unsigned long cr3;
unsigned long resv4;
unsigned long cr4;
};
/* CR1 */
#define SH_SPI_TBE 0x80
#define SH_SPI_TBF 0x40
#define SH_SPI_RBE 0x20
#define SH_SPI_RBF 0x10
#define SH_SPI_PFONRD 0x08
#define SH_SPI_SSDB 0x04
#define SH_SPI_SSD 0x02
#define SH_SPI_SSA 0x01
/* CR2 */
#define SH_SPI_RSTF 0x80
#define SH_SPI_LOOPBK 0x40
#define SH_SPI_CPOL 0x20
#define SH_SPI_CPHA 0x10
#define SH_SPI_L1M0 0x08
/* CR3 */
#define SH_SPI_MAX_BYTE 0xFF
/* CR4 */
#define SH_SPI_TBEI 0x80
#define SH_SPI_TBFI 0x40
#define SH_SPI_RBEI 0x20
#define SH_SPI_RBFI 0x10
#define SH_SPI_WPABRT 0x04
#define SH_SPI_SSS 0x01
#define SH_SPI_FIFO_SIZE 32
struct sh_spi {
struct spi_slave slave;
struct sh_spi_regs *regs;
};
static inline struct sh_spi *to_sh_spi(struct spi_slave *slave)
{
return container_of(slave, struct sh_spi, slave);
}
#endif