spi: add spi controller v3 master driver for Blackfin

New spi controller(version 3) is integrated into Blackfin
60x processor. Comparing to bf5xx spi controller, we support
32 bits word size and independent receive and transmit DMA
channels now. Also mode 0 and 2 (CPHA = 0) can get fully
supported becasue cs line may be controlled by the software.

Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 973 insertions, 0 deletions

diff --git a/drivers/spi/spi-bfin-v3.c b/drivers/spi/spi-bfin-v3.c
new file mode 100644
index 000000000000..603d7e91085b
--- /dev/null
+++ b/drivers/spi/spi-bfin-v3.c
@@ -0,0 +1,973 @@
+/*
+ * Analog Devices SPI3 controller driver
+ *
+ * Copyright (c) 2013 Analog Devices Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+
+#include <asm/bfin_spi3.h>
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/portmux.h>
+
+enum bfin_spi_state {
+	START_STATE,
+	RUNNING_STATE,
+	DONE_STATE,
+	ERROR_STATE
+};
+
+struct bfin_spi_master;
+
+struct bfin_spi_transfer_ops {
+	void (*write) (struct bfin_spi_master *);
+	void (*read) (struct bfin_spi_master *);
+	void (*duplex) (struct bfin_spi_master *);
+};
+
+/* runtime info for spi master */
+struct bfin_spi_master {
+	/* SPI framework hookup */
+	struct spi_master *master;
+
+	/* Regs base of SPI controller */
+	struct bfin_spi_regs __iomem *regs;
+
+	/* Pin request list */
+	u16 *pin_req;
+
+	/* Message Transfer pump */
+	struct tasklet_struct pump_transfers;
+
+	/* Current message transfer state info */
+	struct spi_message *cur_msg;
+	struct spi_transfer *cur_transfer;
+	struct bfin_spi_device *cur_chip;
+	unsigned transfer_len;
+
+	/* transfer buffer */
+	void *tx;
+	void *tx_end;
+	void *rx;
+	void *rx_end;
+
+	/* dma info */
+	unsigned int tx_dma;
+	unsigned int rx_dma;
+	dma_addr_t tx_dma_addr;
+	dma_addr_t rx_dma_addr;
+	unsigned long dummy_buffer; /* used in unidirectional transfer */
+	unsigned long tx_dma_size;
+	unsigned long rx_dma_size;
+	int tx_num;
+	int rx_num;
+
+	/* store register value for suspend/resume */
+	u32 control;
+	u32 ssel;
+
+	unsigned long sclk;
+	enum bfin_spi_state state;
+
+	const struct bfin_spi_transfer_ops *ops;
+};
+
+struct bfin_spi_device {
+	u32 control;
+	u32 clock;
+	u32 ssel;
+
+	u8 cs;
+	u16 cs_chg_udelay; /* Some devices require > 255usec delay */
+	u32 cs_gpio;
+	u32 tx_dummy_val; /* tx value for rx only transfer */
+	bool enable_dma;
+	const struct bfin_spi_transfer_ops *ops;
+};
+
+static void bfin_spi_enable(struct bfin_spi_master *drv_data)
+{
+	bfin_write_or(&drv_data->regs->control, SPI_CTL_EN);
+}
+
+static void bfin_spi_disable(struct bfin_spi_master *drv_data)
+{
+	bfin_write_and(&drv_data->regs->control, ~SPI_CTL_EN);
+}
+
+/* Caculate the SPI_CLOCK register value based on input HZ */
+static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz)
+{
+	u32 spi_clock = sclk / speed_hz;
+
+	if (spi_clock)
+		spi_clock--;
+	return spi_clock;
+}
+
+static int bfin_spi_flush(struct bfin_spi_master *drv_data)
+{
+	unsigned long limit = loops_per_jiffy << 1;
+
+	/* wait for stop and clear stat */
+	while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit)
+		cpu_relax();
+
+	bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+
+	return limit;
+}
+
+/* Chip select operation functions for cs_change flag */
+static void bfin_spi_cs_active(struct bfin_spi_master *drv_data, struct bfin_spi_device *chip)
+{
+	if (likely(chip->cs < MAX_CTRL_CS))
+		bfin_write_and(&drv_data->regs->ssel, ~chip->ssel);
+	else
+		gpio_set_value(chip->cs_gpio, 0);
+}
+
+static void bfin_spi_cs_deactive(struct bfin_spi_master *drv_data,
+				struct bfin_spi_device *chip)
+{
+	if (likely(chip->cs < MAX_CTRL_CS))
+		bfin_write_or(&drv_data->regs->ssel, chip->ssel);
+	else
+		gpio_set_value(chip->cs_gpio, 1);
+
+	/* Move delay here for consistency */
+	if (chip->cs_chg_udelay)
+		udelay(chip->cs_chg_udelay);
+}
+
+/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
+static inline void bfin_spi_cs_enable(struct bfin_spi_master *drv_data,
+					struct bfin_spi_device *chip)
+{
+	if (chip->cs < MAX_CTRL_CS)
+		bfin_write_or(&drv_data->regs->ssel, chip->ssel >> 8);
+}
+
+static inline void bfin_spi_cs_disable(struct bfin_spi_master *drv_data,
+					struct bfin_spi_device *chip)
+{
+	if (chip->cs < MAX_CTRL_CS)
+		bfin_write_and(&drv_data->regs->ssel, ~(chip->ssel >> 8));
+}
+
+/* stop controller and re-config current chip*/
+static void bfin_spi_restore_state(struct bfin_spi_master *drv_data)
+{
+	struct bfin_spi_device *chip = drv_data->cur_chip;
+
+	/* Clear status and disable clock */
+	bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+	bfin_write(&drv_data->regs->rx_control, 0x0);
+	bfin_write(&drv_data->regs->tx_control, 0x0);
+	bfin_spi_disable(drv_data);
+
+	SSYNC();
+
+	/* Load the registers */
+	bfin_write(&drv_data->regs->control, chip->control);
+	bfin_write(&drv_data->regs->clock, chip->clock);
+
+	bfin_spi_enable(drv_data);
+	drv_data->tx_num = drv_data->rx_num = 0;
+	/* we always choose tx transfer initiate */
+	bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN);
+	bfin_write(&drv_data->regs->tx_control,
+			SPI_TXCTL_TEN | SPI_TXCTL_TTI);
+	bfin_spi_cs_active(drv_data, chip);
+}
+
+/* discard invalid rx data and empty rfifo */
+static inline void dummy_read(struct bfin_spi_master *drv_data)
+{
+	while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_RFE))
+		bfin_read(&drv_data->regs->rfifo);
+}
+
+static void bfin_spi_u8_write(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->tx < drv_data->tx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		bfin_read(&drv_data->regs->rfifo);
+	}
+}
+
+static void bfin_spi_u8_read(struct bfin_spi_master *drv_data)
+{
+	u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, tx_val);
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
+	}
+}
+
+static void bfin_spi_u8_duplex(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
+	}
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = {
+	.write  = bfin_spi_u8_write,
+	.read   = bfin_spi_u8_read,
+	.duplex = bfin_spi_u8_duplex,
+};
+
+static void bfin_spi_u16_write(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->tx < drv_data->tx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
+		drv_data->tx += 2;
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		bfin_read(&drv_data->regs->rfifo);
+	}
+}
+
+static void bfin_spi_u16_read(struct bfin_spi_master *drv_data)
+{
+	u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, tx_val);
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+		drv_data->rx += 2;
+	}
+}
+
+static void bfin_spi_u16_duplex(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
+		drv_data->tx += 2;
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+		drv_data->rx += 2;
+	}
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = {
+	.write  = bfin_spi_u16_write,
+	.read   = bfin_spi_u16_read,
+	.duplex = bfin_spi_u16_duplex,
+};
+
+static void bfin_spi_u32_write(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->tx < drv_data->tx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
+		drv_data->tx += 4;
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		bfin_read(&drv_data->regs->rfifo);
+	}
+}
+
+static void bfin_spi_u32_read(struct bfin_spi_master *drv_data)
+{
+	u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, tx_val);
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+		drv_data->rx += 4;
+	}
+}
+
+static void bfin_spi_u32_duplex(struct bfin_spi_master *drv_data)
+{
+	dummy_read(drv_data);
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
+		drv_data->tx += 4;
+		while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+			cpu_relax();
+		*(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+		drv_data->rx += 4;
+	}
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u32 = {
+	.write  = bfin_spi_u32_write,
+	.read   = bfin_spi_u32_read,
+	.duplex = bfin_spi_u32_duplex,
+};
+
+
+/* test if there is more transfer to be done */
+static void bfin_spi_next_transfer(struct bfin_spi_master *drv)
+{
+	struct spi_message *msg = drv->cur_msg;
+	struct spi_transfer *t = drv->cur_transfer;
+
+	/* Move to next transfer */
+	if (t->transfer_list.next != &msg->transfers) {
+		drv->cur_transfer = list_entry(t->transfer_list.next,
+			       struct spi_transfer, transfer_list);
+		drv->state = RUNNING_STATE;
+	} else {
+		drv->state = DONE_STATE;
+		drv->cur_transfer = NULL;
+	}
+}
+
+static void bfin_spi_giveback(struct bfin_spi_master *drv_data)
+{
+	struct bfin_spi_device *chip = drv_data->cur_chip;
+
+	bfin_spi_cs_deactive(drv_data, chip);
+	spi_finalize_current_message(drv_data->master);
+}
+
+static int bfin_spi_setup_transfer(struct bfin_spi_master *drv)
+{
+	struct spi_transfer *t = drv->cur_transfer;
+	u32 cr, cr_width;
+
+	if (t->tx_buf) {
+		drv->tx = (void *)t->tx_buf;
+		drv->tx_end = drv->tx + t->len;
+	} else {
+		drv->tx = NULL;
+	}
+
+	if (t->rx_buf) {
+		drv->rx = t->rx_buf;
+		drv->rx_end = drv->rx + t->len;
+	} else {
+		drv->rx = NULL;
+	}
+
+	drv->transfer_len = t->len;
+
+	/* bits per word setup */
+	switch (t->bits_per_word) {
+	case 8:
+		cr_width = SPI_CTL_SIZE08;
+		drv->ops = &bfin_bfin_spi_transfer_ops_u8;
+		break;
+	case 16:
+		cr_width = SPI_CTL_SIZE16;
+		drv->ops = &bfin_bfin_spi_transfer_ops_u16;
+		break;
+	case 32:
+		cr_width = SPI_CTL_SIZE32;
+		drv->ops = &bfin_bfin_spi_transfer_ops_u32;
+		break;
+	default:
+		return -EINVAL;
+	}
+	cr = bfin_read(&drv->regs->control) & ~SPI_CTL_SIZE;
+	cr |= cr_width;
+	bfin_write(&drv->regs->control, cr);
+
+	/* speed setup */
+	bfin_write(&drv->regs->clock,
+			hz_to_spi_clock(drv->sclk, t->speed_hz));
+	return 0;
+}
+
+static int bfin_spi_dma_xfer(struct bfin_spi_master *drv_data)
+{
+	struct spi_transfer *t = drv_data->cur_transfer;
+	struct spi_message *msg = drv_data->cur_msg;
+	struct bfin_spi_device *chip = drv_data->cur_chip;
+	u32 dma_config;
+	unsigned long word_count, word_size;
+	void *tx_buf, *rx_buf;
+
+	switch (t->bits_per_word) {
+	case 8:
+		dma_config = WDSIZE_8 | PSIZE_8;
+		word_count = drv_data->transfer_len;
+		word_size = 1;
+		break;
+	case 16:
+		dma_config = WDSIZE_16 | PSIZE_16;
+		word_count = drv_data->transfer_len / 2;
+		word_size = 2;
+		break;
+	default:
+		dma_config = WDSIZE_32 | PSIZE_32;
+		word_count = drv_data->transfer_len / 4;
+		word_size = 4;
+		break;
+	}
+
+	if (!drv_data->rx) {
+		tx_buf = drv_data->tx;
+		rx_buf = &drv_data->dummy_buffer;
+		drv_data->tx_dma_size = drv_data->transfer_len;
+		drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer);
+		set_dma_x_modify(drv_data->tx_dma, word_size);
+		set_dma_x_modify(drv_data->rx_dma, 0);
+	} else if (!drv_data->tx) {
+		drv_data->dummy_buffer = chip->tx_dummy_val;
+		tx_buf = &drv_data->dummy_buffer;
+		rx_buf = drv_data->rx;
+		drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer);
+		drv_data->rx_dma_size = drv_data->transfer_len;
+		set_dma_x_modify(drv_data->tx_dma, 0);
+		set_dma_x_modify(drv_data->rx_dma, word_size);
+	} else {
+		tx_buf = drv_data->tx;
+		rx_buf = drv_data->rx;
+		drv_data->tx_dma_size = drv_data->rx_dma_size
+					= drv_data->transfer_len;
+		set_dma_x_modify(drv_data->tx_dma, word_size);
+		set_dma_x_modify(drv_data->rx_dma, word_size);
+	}
+
+	drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev,
+				(void *)tx_buf,
+				drv_data->tx_dma_size,
+				DMA_TO_DEVICE);
+	if (dma_mapping_error(&msg->spi->dev,
+				drv_data->tx_dma_addr))
+		return -ENOMEM;
+
+	drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev,
+				(void *)rx_buf,
+				drv_data->rx_dma_size,
+				DMA_FROM_DEVICE);
+	if (dma_mapping_error(&msg->spi->dev,
+				drv_data->rx_dma_addr)) {
+		dma_unmap_single(&msg->spi->dev,
+				drv_data->tx_dma_addr,
+				drv_data->tx_dma_size,
+				DMA_TO_DEVICE);
+		return -ENOMEM;
+	}
+
+	dummy_read(drv_data);
+	set_dma_x_count(drv_data->tx_dma, word_count);
+	set_dma_x_count(drv_data->rx_dma, word_count);
+	set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr);
+	set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr);
+	dma_config |= DMAFLOW_STOP | RESTART | DI_EN;
+	set_dma_config(drv_data->tx_dma, dma_config);
+	set_dma_config(drv_data->rx_dma, dma_config | WNR);
+	enable_dma(drv_data->tx_dma);
+	enable_dma(drv_data->rx_dma);
+	SSYNC();
+
+	bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN | SPI_RXCTL_RDR_NE);
+	SSYNC();
+	bfin_write(&drv_data->regs->tx_control,
+			SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF);
+
+	return 0;
+}
+
+static int bfin_spi_pio_xfer(struct bfin_spi_master *drv_data)
+{
+	struct spi_message *msg = drv_data->cur_msg;
+
+	if (!drv_data->rx) {
+		/* write only half duplex */
+		drv_data->ops->write(drv_data);
+		if (drv_data->tx != drv_data->tx_end)
+			return -EIO;
+	} else if (!drv_data->tx) {
+		/* read only half duplex */
+		drv_data->ops->read(drv_data);
+		if (drv_data->rx != drv_data->rx_end)
+			return -EIO;
+	} else {
+		/* full duplex mode */
+		drv_data->ops->duplex(drv_data);
+		if (drv_data->tx != drv_data->tx_end)
+			return -EIO;
+	}
+
+	if (!bfin_spi_flush(drv_data))
+		return -EIO;
+	msg->actual_length += drv_data->transfer_len;
+	tasklet_schedule(&drv_data->pump_transfers);
+	return 0;
+}
+
+static void bfin_spi_pump_transfers(unsigned long data)
+{
+	struct bfin_spi_master *drv_data = (struct bfin_spi_master *)data;
+	struct spi_message *msg = NULL;
+	struct spi_transfer *t = NULL;
+	struct bfin_spi_device *chip = NULL;
+	int ret;
+
+	/* Get current state information */
+	msg = drv_data->cur_msg;
+	t = drv_data->cur_transfer;
+	chip = drv_data->cur_chip;
+
+	/* Handle for abort */
+	if (drv_data->state == ERROR_STATE) {
+		msg->status = -EIO;
+		bfin_spi_giveback(drv_data);
+		return;
+	}
+
+	if (drv_data->state == RUNNING_STATE) {
+		if (t->delay_usecs)
+			udelay(t->delay_usecs);
+		if (t->cs_change)
+			bfin_spi_cs_deactive(drv_data, chip);
+		bfin_spi_next_transfer(drv_data);
+		t = drv_data->cur_transfer;
+	}
+	/* Handle end of message */
+	if (drv_data->state == DONE_STATE) {
+		msg->status = 0;
+		bfin_spi_giveback(drv_data);
+		return;
+	}
+
+	if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) {
+		/* Schedule next transfer tasklet */
+		tasklet_schedule(&drv_data->pump_transfers);
+		return;
+	}
+
+	ret = bfin_spi_setup_transfer(drv_data);
+	if (ret) {
+		msg->status = ret;
+		bfin_spi_giveback(drv_data);
+	}
+
+	bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+	bfin_spi_cs_active(drv_data, chip);
+	drv_data->state = RUNNING_STATE;
+
+	if (chip->enable_dma)
+		ret = bfin_spi_dma_xfer(drv_data);
+	else
+		ret = bfin_spi_pio_xfer(drv_data);
+	if (ret) {
+		msg->status = ret;
+		bfin_spi_giveback(drv_data);
+	}
+}
+
+static int bfin_spi_transfer_one_message(struct spi_master *master,
+					struct spi_message *m)
+{
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+	drv_data->cur_msg = m;
+	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
+	bfin_spi_restore_state(drv_data);
+
+	drv_data->state = START_STATE;
+	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
+					    struct spi_transfer, transfer_list);
+
+	tasklet_schedule(&drv_data->pump_transfers);
+	return 0;
+}
+
+#define MAX_SPI_SSEL	7
+
+static const u16 ssel[][MAX_SPI_SSEL] = {
+	{P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
+	P_SPI0_SSEL4, P_SPI0_SSEL5,
+	P_SPI0_SSEL6, P_SPI0_SSEL7},
+
+	{P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
+	P_SPI1_SSEL4, P_SPI1_SSEL5,
+	P_SPI1_SSEL6, P_SPI1_SSEL7},
+
+	{P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
+	P_SPI2_SSEL4, P_SPI2_SSEL5,
+	P_SPI2_SSEL6, P_SPI2_SSEL7},
+};
+
+static int bfin_spi_setup(struct spi_device *spi)
+{
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
+	struct bfin_spi_device *chip = spi_get_ctldata(spi);
+	u32 bfin_ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE;
+	int ret = -EINVAL;
+
+	if (!chip) {
+		struct bfin_spi3_chip *chip_info = spi->controller_data;
+
+		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+		if (!chip) {
+			dev_err(&spi->dev, "can not allocate chip data\n");
+			return -ENOMEM;
+		}
+		if (chip_info) {
+			if (chip_info->control & ~bfin_ctl_reg) {
+				dev_err(&spi->dev,
+					"do not set bits that the SPI framework manages\n");
+				goto error;
+			}
+			chip->control = chip_info->control;
+			chip->cs_chg_udelay = chip_info->cs_chg_udelay;
+			chip->tx_dummy_val = chip_info->tx_dummy_val;
+			chip->enable_dma = chip_info->enable_dma;
+		}
+		chip->cs = spi->chip_select;
+		if (chip->cs < MAX_CTRL_CS) {
+			chip->ssel = (1 << chip->cs) << 8;
+			ret = peripheral_request(ssel[spi->master->bus_num]
+					[chip->cs-1], dev_name(&spi->dev));
+			if (ret) {
+				dev_err(&spi->dev, "peripheral_request() error\n");
+				goto error;
+			}
+		} else {
+			chip->cs_gpio = chip->cs - MAX_CTRL_CS;
+			ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH,
+						dev_name(&spi->dev));
+			if (ret) {
+				dev_err(&spi->dev, "gpio_request_one() error\n");
+				goto error;
+			}
+		}
+		spi_set_ctldata(spi, chip);
+	}
+
+	/* force a default base state */
+	chip->control &= bfin_ctl_reg;
+
+	if (spi->mode & SPI_CPOL)
+		chip->control |= SPI_CTL_CPOL;
+	if (spi->mode & SPI_CPHA)
+		chip->control |= SPI_CTL_CPHA;
+	if (spi->mode & SPI_LSB_FIRST)
+		chip->control |= SPI_CTL_LSBF;
+	chip->control |= SPI_CTL_MSTR;
+	/* we choose software to controll cs */
+	chip->control &= ~SPI_CTL_ASSEL;
+
+	chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz);
+
+	bfin_spi_cs_enable(drv_data, chip);
+	bfin_spi_cs_deactive(drv_data, chip);
+
+	return 0;
+error:
+	if (chip) {
+		kfree(chip);
+		spi_set_ctldata(spi, NULL);
+	}
+
+	return ret;
+}
+
+static void bfin_spi_cleanup(struct spi_device *spi)
+{
+	struct bfin_spi_device *chip = spi_get_ctldata(spi);
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
+
+	if (!chip)
+		return;
+
+	if (chip->cs < MAX_CTRL_CS) {
+		peripheral_free(ssel[spi->master->bus_num]
+					[chip->cs-1]);
+		bfin_spi_cs_disable(drv_data, chip);
+	} else {
+		gpio_free(chip->cs_gpio);
+	}
+
+	kfree(chip);
+	spi_set_ctldata(spi, NULL);
+}
+
+static irqreturn_t bfin_spi_tx_dma_isr(int irq, void *dev_id)
+{
+	struct bfin_spi_master *drv_data = dev_id;
+	u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma);
+
+	clear_dma_irqstat(drv_data->tx_dma);
+	if (dma_stat & DMA_DONE) {
+		drv_data->tx_num++;
+	} else {
+		dev_err(&drv_data->master->dev,
+				"spi tx dma error: %d\n", dma_stat);
+		if (drv_data->tx)
+			drv_data->state = ERROR_STATE;
+	}
+	bfin_write_and(&drv_data->regs->tx_control, ~SPI_TXCTL_TDR_NF);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t bfin_spi_rx_dma_isr(int irq, void *dev_id)
+{
+	struct bfin_spi_master *drv_data = dev_id;
+	struct spi_message *msg = drv_data->cur_msg;
+	u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma);
+
+	clear_dma_irqstat(drv_data->rx_dma);
+	if (dma_stat & DMA_DONE) {
+		drv_data->rx_num++;
+		/* we may fail on tx dma */
+		if (drv_data->state != ERROR_STATE)
+			msg->actual_length += drv_data->transfer_len;
+	} else {
+		drv_data->state = ERROR_STATE;
+		dev_err(&drv_data->master->dev,
+				"spi rx dma error: %d\n", dma_stat);
+	}
+	bfin_write(&drv_data->regs->tx_control, 0);
+	bfin_write(&drv_data->regs->rx_control, 0);
+	if (drv_data->rx_num != drv_data->tx_num)
+		dev_dbg(&drv_data->master->dev,
+				"dma interrupt missing: tx=%d,rx=%d\n",
+				drv_data->tx_num, drv_data->rx_num);
+	tasklet_schedule(&drv_data->pump_transfers);
+	return IRQ_HANDLED;
+}
+
+static int bfin_spi_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct bfin_spi3_master *info = dev->platform_data;
+	struct spi_master *master;
+	struct bfin_spi_master *drv_data;
+	struct resource *mem, *res;
+	unsigned int tx_dma, rx_dma;
+	unsigned long sclk;
+	int ret;
+
+	if (!info) {
+		dev_err(dev, "platform data missing!\n");
+		return -ENODEV;
+	}
+
+	sclk = get_sclk1();
+	if (!sclk) {
+		dev_err(dev, "can not get sclk1\n");
+		return -ENXIO;
+	}
+
+	/* get register base and tx/rx dma */
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(dev, "can not get register base\n");
+		return -ENXIO;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	if (!res) {
+		dev_err(dev, "can not get tx dma resource\n");
+		return -ENXIO;
+	}
+	tx_dma = res->start;
+
+	res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+	if (!res) {
+		dev_err(dev, "can not get rx dma resource\n");
+		return -ENXIO;
+	}
+	rx_dma = res->start;
+
+	/* allocate master with space for drv_data */
+	master = spi_alloc_master(dev, sizeof(*drv_data));
+	if (!master) {
+		dev_err(dev, "can not alloc spi_master\n");
+		return -ENOMEM;
+	}
+	platform_set_drvdata(pdev, master);
+
+	/* the mode bits supported by this driver */
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+
+	master->bus_num = pdev->id;
+	master->num_chipselect = info->num_chipselect;
+	master->cleanup = bfin_spi_cleanup;
+	master->setup = bfin_spi_setup;
+	master->transfer_one_message = bfin_spi_transfer_one_message;
+	master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
+
+	drv_data = spi_master_get_devdata(master);
+	drv_data->master = master;
+	drv_data->tx_dma = tx_dma;
+	drv_data->rx_dma = rx_dma;
+	drv_data->pin_req = info->pin_req;
+	drv_data->sclk = sclk;
+
+	drv_data->regs = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(drv_data->regs)) {
+		ret = PTR_ERR(drv_data->regs);
+		goto err_put_master;
+	}
+
+	/* request tx and rx dma */
+	ret = request_dma(tx_dma, "SPI_TX_DMA");
+	if (ret) {
+		dev_err(dev, "can not request SPI TX DMA channel\n");
+		goto err_put_master;
+	}
+	set_dma_callback(tx_dma, bfin_spi_tx_dma_isr, drv_data);
+
+	ret = request_dma(rx_dma, "SPI_RX_DMA");
+	if (ret) {
+		dev_err(dev, "can not request SPI RX DMA channel\n");
+		goto err_free_tx_dma;
+	}
+	set_dma_callback(drv_data->rx_dma, bfin_spi_rx_dma_isr, drv_data);
+
+	/* request CLK, MOSI and MISO */
+	ret = peripheral_request_list(drv_data->pin_req, "bfin-spi3");
+	if (ret < 0) {
+		dev_err(dev, "can not request spi pins\n");
+		goto err_free_rx_dma;
+	}
+
+	bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
+	bfin_write(&drv_data->regs->ssel, 0x0000FE00);
+	bfin_write(&drv_data->regs->delay, 0x0);
+
+	tasklet_init(&drv_data->pump_transfers,
+			bfin_spi_pump_transfers, (unsigned long)drv_data);
+	/* register with the SPI framework */
+	ret = spi_register_master(master);
+	if (ret) {
+		dev_err(dev, "can not  register spi master\n");
+		goto err_free_peripheral;
+	}
+
+	return ret;
+
+err_free_peripheral:
+	peripheral_free_list(drv_data->pin_req);
+err_free_rx_dma:
+	free_dma(rx_dma);
+err_free_tx_dma:
+	free_dma(tx_dma);
+err_put_master:
+	platform_set_drvdata(pdev, NULL);
+	spi_master_put(master);
+
+	return ret;
+}
+
+static int bfin_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+	bfin_spi_disable(drv_data);
+
+	peripheral_free_list(drv_data->pin_req);
+	free_dma(drv_data->rx_dma);
+	free_dma(drv_data->tx_dma);
+
+	platform_set_drvdata(pdev, NULL);
+	spi_unregister_master(drv_data->master);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int bfin_spi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+	spi_master_suspend(master);
+
+	drv_data->control = bfin_read(&drv_data->regs->control);
+	drv_data->ssel = bfin_read(&drv_data->regs->ssel);
+
+	bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
+	bfin_write(&drv_data->regs->ssel, 0x0000FE00);
+	dma_disable_irq(drv_data->rx_dma);
+	dma_disable_irq(drv_data->tx_dma);
+
+	return 0;
+}
+
+static int bfin_spi_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+	int ret = 0;
+
+	/* bootrom may modify spi and dma status when resume in spi boot mode */
+	disable_dma(drv_data->rx_dma);
+
+	dma_enable_irq(drv_data->rx_dma);
+	dma_enable_irq(drv_data->tx_dma);
+	bfin_write(&drv_data->regs->control, drv_data->control);
+	bfin_write(&drv_data->regs->ssel, drv_data->ssel);
+
+	ret = spi_master_resume(master);
+	if (ret) {
+		free_dma(drv_data->rx_dma);
+		free_dma(drv_data->tx_dma);
+	}
+
+	return ret;
+}
+#endif
+static const struct dev_pm_ops bfin_spi_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(bfin_spi_suspend, bfin_spi_resume)
+};
+
+MODULE_ALIAS("platform:bfin-spi3");
+static struct platform_driver bfin_spi_driver = {
+	.driver	= {
+		.name	= "bfin-spi3",
+		.owner	= THIS_MODULE,
+		.pm     = &bfin_spi_pm_ops,
+	},
+	.remove		= bfin_spi_remove,
+};
+
+module_platform_driver_probe(bfin_spi_driver, bfin_spi_probe);
+
+MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
+MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
+MODULE_LICENSE("GPL v2");