From 6639562e6a7f2ae3160ef120d18b7796a2ff8e19 Mon Sep 17 00:00:00 2001 From: Yoshihiro Shimoda Date: Mon, 31 Jan 2011 16:50:43 +0900 Subject: [PATCH] spi: add support SuperH SPI module SH7757 has SPI module. This patch supports it. Signed-off-by: Yoshihiro Shimoda Signed-off-by: Nobuhiro Iwamatsu --- README | 5 + drivers/spi/Makefile | 1 + drivers/spi/sh_spi.c | 261 +++++++++++++++++++++++++++++++++++++++++++ drivers/spi/sh_spi.h | 79 +++++++++++++ 4 files changed, 346 insertions(+) create mode 100644 drivers/spi/sh_spi.c create mode 100644 drivers/spi/sh_spi.h diff --git a/README b/README index e005bc5a04..37eda1156c 100644 --- a/README +++ b/README @@ -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. diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index e34a124239..d582fbbb17 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -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) diff --git a/drivers/spi/sh_spi.c b/drivers/spi/sh_spi.c new file mode 100644 index 0000000000..ba43bec8bf --- /dev/null +++ b/drivers/spi/sh_spi.c @@ -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 +#include +#include +#include +#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) +{ + +} + diff --git a/drivers/spi/sh_spi.h b/drivers/spi/sh_spi.h new file mode 100644 index 0000000000..b1cf98cc33 --- /dev/null +++ b/drivers/spi/sh_spi.h @@ -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 + +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 + -- 2.30.2