diff mbox

[v2] spi: add spi controller master driver for Blackfin 6xx processor

Message ID 1371583828-23788-1-git-send-email-scott.jiang.linux@gmail.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Scott Jiang June 18, 2013, 7:30 p.m. UTC
New spi controller is integrated into Blackfin 6xx 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>
---
 drivers/spi/Kconfig       |    8 +-
 drivers/spi/Makefile      |    1 +
 drivers/spi/spi-bfin6xx.c |  996 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1004 insertions(+), 1 deletions(-)
 create mode 100644 drivers/spi/spi-bfin6xx.c

Comments

Scott Jiang June 21, 2013, 4:48 a.m. UTC | #1
Hi Mark,
>
>> +MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
>
> Why not call the driver something like bfin_spi3 then?

Do you mean the driver name or file name? It's the same with spi-bfin5xx driver.
The test script may use the same name for 5xx and 6xx boards.

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Scott Jiang June 26, 2013, 5:06 a.m. UTC | #2
Hi Mark,

>
>> +     switch (spi->bits_per_word) {
>> +     case 8:
>> +     case 16:
>> +     case 32:
>> +             break;
>> +     default:
>> +             dev_err(&spi->dev, "%d bits_per_word is not supported\n",
>> +                             spi->bits_per_word);
>> +             return -EINVAL;
>> +     }
>
> Just set bits_per_word_mask in the master struct and let the core do
> this for you.
>
This check is in spi_setup, but master->bits_per_word_mask check is delayed to
each transfer. Don't you think master->bits_per_word_mask also should be tested
in spi_setup?

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Scott Jiang July 19, 2013, 9:07 a.m. UTC | #3
Hi Mark,

>
>> +static int __init bfin_spi_init(void)
>> +{
>> +     return platform_driver_probe(&bfin_spi_driver, bfin_spi_probe);
>> +}
>> +subsys_initcall(bfin_spi_init);
>
> Should really use module_platform_driver() on modern systems, the
> deferred probe infrastructure should remove the need for faffing around
> with init order.
>
When I convert to use module_platform_driver(), I found some driver depend on
SPI_MASTER start up before spi master probe driver. So how can I control this
init order?

Thanks,
Scott

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Scott Jiang July 19, 2013, 10:22 a.m. UTC | #4
Hi Mark,

>> > Should really use module_platform_driver() on modern systems, the
>> > deferred probe infrastructure should remove the need for faffing around
>> > with init order.
>
>> When I convert to use module_platform_driver(), I found some driver depend on
>> SPI_MASTER start up before spi master probe driver. So how can I control this
>> init order?
>
> Could you be more explicit about the dependencies here?  Are these other
> drivers using -EPROBE_DEFER as they should?

No, it returns ENODEV if spi_busnum_to_master(0) fail. It's a fb
driver and /drivers/video
is before /drivers/spi in link order. So I should do more work on this
fb driver instead of
spi master driver to make probe deferral mechanism work, right?

Scott

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diff mbox

Patch

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 864d87f..d64bbeb 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -87,10 +87,16 @@  config SPI_BCM2835
 
 config SPI_BFIN5XX
 	tristate "SPI controller driver for ADI Blackfin5xx"
-	depends on BLACKFIN
+	depends on BLACKFIN && !BF60x
 	help
 	  This is the SPI controller master driver for Blackfin 5xx processor.
 
+config SPI_BFIN6XX
+	tristate "SPI controller driver for ADI Blackfin6xx"
+	depends on BF60x
+	help
+	  This is the SPI controller master driver for Blackfin 6xx processor.
+
 config SPI_BFIN_SPORT
 	tristate "SPI bus via Blackfin SPORT"
 	depends on BLACKFIN
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 33f9c09..0114a26 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -17,6 +17,7 @@  obj-$(CONFIG_SPI_AU1550)		+= spi-au1550.o
 obj-$(CONFIG_SPI_BCM2835)		+= spi-bcm2835.o
 obj-$(CONFIG_SPI_BCM63XX)		+= spi-bcm63xx.o
 obj-$(CONFIG_SPI_BFIN5XX)		+= spi-bfin5xx.o
+obj-$(CONFIG_SPI_BFIN6XX)               += spi-bfin6xx.o
 obj-$(CONFIG_SPI_BFIN_SPORT)		+= spi-bfin-sport.o
 obj-$(CONFIG_SPI_BITBANG)		+= spi-bitbang.o
 obj-$(CONFIG_SPI_BUTTERFLY)		+= spi-butterfly.o
diff --git a/drivers/spi/spi-bfin6xx.c b/drivers/spi/spi-bfin6xx.c
new file mode 100644
index 0000000..6c9bae3
--- /dev/null
+++ b/drivers/spi/spi-bfin6xx.c
@@ -0,0 +1,996 @@ 
+/*
+ * 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/bfin6xx_spi.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;
+
+	switch (spi->bits_per_word) {
+	case 8:
+	case 16:
+	case 32:
+		break;
+	default:
+		dev_err(&spi->dev, "%d bits_per_word is not supported\n",
+				spi->bits_per_word);
+		return -EINVAL;
+	}
+
+	if (!chip) {
+		struct bfin6xx_spi_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 bfin6xx_spi_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;
+
+	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)) {
+		dev_err(dev, "can not map register memory\n");
+		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-spi");
+	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;
+}
+static const struct dev_pm_ops bfin_spi_pm_ops = {
+	.suspend = bfin_spi_suspend,
+	.resume  = bfin_spi_resume,
+};
+#endif /* CONFIG_PM */
+
+MODULE_ALIAS("platform:bfin-spi");
+static struct platform_driver bfin_spi_driver = {
+	.driver	= {
+		.name	= "bfin-spi",
+		.owner	= THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm     = &bfin_spi_pm_ops,
+#endif
+	},
+	.remove		= bfin_spi_remove,
+};
+
+static int __init bfin_spi_init(void)
+{
+	return platform_driver_probe(&bfin_spi_driver, bfin_spi_probe);
+}
+subsys_initcall(bfin_spi_init);
+
+static void __exit bfin_spi_exit(void)
+{
+	platform_driver_unregister(&bfin_spi_driver);
+}
+module_exit(bfin_spi_exit);
+
+MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
+MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
+MODULE_LICENSE("GPL v2");