X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fspi%2Fspi-sirf.c;fp=kernel%2Fdrivers%2Fspi%2Fspi-sirf.c;h=f5715c9f68b0e0cb3dd2f7f568fed38798820796;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git

diff --git a/kernel/drivers/spi/spi-sirf.c b/kernel/drivers/spi/spi-sirf.c
new file mode 100644
index 000000000..f5715c9f6
--- /dev/null
+++ b/kernel/drivers/spi/spi-sirf.c
@@ -0,0 +1,838 @@
+/*
+ * SPI bus driver for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/of_gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/reset.h>
+
+#define DRIVER_NAME "sirfsoc_spi"
+
+#define SIRFSOC_SPI_CTRL		0x0000
+#define SIRFSOC_SPI_CMD			0x0004
+#define SIRFSOC_SPI_TX_RX_EN		0x0008
+#define SIRFSOC_SPI_INT_EN		0x000C
+#define SIRFSOC_SPI_INT_STATUS		0x0010
+#define SIRFSOC_SPI_TX_DMA_IO_CTRL	0x0100
+#define SIRFSOC_SPI_TX_DMA_IO_LEN	0x0104
+#define SIRFSOC_SPI_TXFIFO_CTRL		0x0108
+#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK	0x010C
+#define SIRFSOC_SPI_TXFIFO_OP		0x0110
+#define SIRFSOC_SPI_TXFIFO_STATUS	0x0114
+#define SIRFSOC_SPI_TXFIFO_DATA		0x0118
+#define SIRFSOC_SPI_RX_DMA_IO_CTRL	0x0120
+#define SIRFSOC_SPI_RX_DMA_IO_LEN	0x0124
+#define SIRFSOC_SPI_RXFIFO_CTRL		0x0128
+#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK	0x012C
+#define SIRFSOC_SPI_RXFIFO_OP		0x0130
+#define SIRFSOC_SPI_RXFIFO_STATUS	0x0134
+#define SIRFSOC_SPI_RXFIFO_DATA		0x0138
+#define SIRFSOC_SPI_DUMMY_DELAY_CTL	0x0144
+
+/* SPI CTRL register defines */
+#define SIRFSOC_SPI_SLV_MODE		BIT(16)
+#define SIRFSOC_SPI_CMD_MODE		BIT(17)
+#define SIRFSOC_SPI_CS_IO_OUT		BIT(18)
+#define SIRFSOC_SPI_CS_IO_MODE		BIT(19)
+#define SIRFSOC_SPI_CLK_IDLE_STAT	BIT(20)
+#define SIRFSOC_SPI_CS_IDLE_STAT	BIT(21)
+#define SIRFSOC_SPI_TRAN_MSB		BIT(22)
+#define SIRFSOC_SPI_DRV_POS_EDGE	BIT(23)
+#define SIRFSOC_SPI_CS_HOLD_TIME	BIT(24)
+#define SIRFSOC_SPI_CLK_SAMPLE_MODE	BIT(25)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8	(0 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12	(1 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16	(2 << 26)
+#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32	(3 << 26)
+#define SIRFSOC_SPI_CMD_BYTE_NUM(x)	((x & 3) << 28)
+#define SIRFSOC_SPI_ENA_AUTO_CLR	BIT(30)
+#define SIRFSOC_SPI_MUL_DAT_MODE	BIT(31)
+
+/* Interrupt Enable */
+#define SIRFSOC_SPI_RX_DONE_INT_EN	BIT(0)
+#define SIRFSOC_SPI_TX_DONE_INT_EN	BIT(1)
+#define SIRFSOC_SPI_RX_OFLOW_INT_EN	BIT(2)
+#define SIRFSOC_SPI_TX_UFLOW_INT_EN	BIT(3)
+#define SIRFSOC_SPI_RX_IO_DMA_INT_EN	BIT(4)
+#define SIRFSOC_SPI_TX_IO_DMA_INT_EN	BIT(5)
+#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN	BIT(6)
+#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN	BIT(7)
+#define SIRFSOC_SPI_RXFIFO_THD_INT_EN	BIT(8)
+#define SIRFSOC_SPI_TXFIFO_THD_INT_EN	BIT(9)
+#define SIRFSOC_SPI_FRM_END_INT_EN	BIT(10)
+
+#define SIRFSOC_SPI_INT_MASK_ALL	0x1FFF
+
+/* Interrupt status */
+#define SIRFSOC_SPI_RX_DONE		BIT(0)
+#define SIRFSOC_SPI_TX_DONE		BIT(1)
+#define SIRFSOC_SPI_RX_OFLOW		BIT(2)
+#define SIRFSOC_SPI_TX_UFLOW		BIT(3)
+#define SIRFSOC_SPI_RX_IO_DMA		BIT(4)
+#define SIRFSOC_SPI_RX_FIFO_FULL	BIT(6)
+#define SIRFSOC_SPI_TXFIFO_EMPTY	BIT(7)
+#define SIRFSOC_SPI_RXFIFO_THD_REACH	BIT(8)
+#define SIRFSOC_SPI_TXFIFO_THD_REACH	BIT(9)
+#define SIRFSOC_SPI_FRM_END		BIT(10)
+
+/* TX RX enable */
+#define SIRFSOC_SPI_RX_EN		BIT(0)
+#define SIRFSOC_SPI_TX_EN		BIT(1)
+#define SIRFSOC_SPI_CMD_TX_EN		BIT(2)
+
+#define SIRFSOC_SPI_IO_MODE_SEL		BIT(0)
+#define SIRFSOC_SPI_RX_DMA_FLUSH	BIT(2)
+
+/* FIFO OPs */
+#define SIRFSOC_SPI_FIFO_RESET		BIT(0)
+#define SIRFSOC_SPI_FIFO_START		BIT(1)
+
+/* FIFO CTRL */
+#define SIRFSOC_SPI_FIFO_WIDTH_BYTE	(0 << 0)
+#define SIRFSOC_SPI_FIFO_WIDTH_WORD	(1 << 0)
+#define SIRFSOC_SPI_FIFO_WIDTH_DWORD	(2 << 0)
+
+/* FIFO Status */
+#define	SIRFSOC_SPI_FIFO_LEVEL_MASK	0xFF
+#define SIRFSOC_SPI_FIFO_FULL		BIT(8)
+#define SIRFSOC_SPI_FIFO_EMPTY		BIT(9)
+
+/* 256 bytes rx/tx FIFO */
+#define SIRFSOC_SPI_FIFO_SIZE		256
+#define SIRFSOC_SPI_DAT_FRM_LEN_MAX	(64 * 1024)
+
+#define SIRFSOC_SPI_FIFO_SC(x)		((x) & 0x3F)
+#define SIRFSOC_SPI_FIFO_LC(x)		(((x) & 0x3F) << 10)
+#define SIRFSOC_SPI_FIFO_HC(x)		(((x) & 0x3F) << 20)
+#define SIRFSOC_SPI_FIFO_THD(x)		(((x) & 0xFF) << 2)
+
+/*
+ * only if the rx/tx buffer and transfer size are 4-bytes aligned, we use dma
+ * due to the limitation of dma controller
+ */
+
+#define ALIGNED(x) (!((u32)x & 0x3))
+#define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \
+	ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE))
+
+#define SIRFSOC_MAX_CMD_BYTES	4
+#define SIRFSOC_SPI_DEFAULT_FRQ 1000000
+
+struct sirfsoc_spi {
+	struct spi_bitbang bitbang;
+	struct completion rx_done;
+	struct completion tx_done;
+
+	void __iomem *base;
+	u32 ctrl_freq;  /* SPI controller clock speed */
+	struct clk *clk;
+
+	/* rx & tx bufs from the spi_transfer */
+	const void *tx;
+	void *rx;
+
+	/* place received word into rx buffer */
+	void (*rx_word) (struct sirfsoc_spi *);
+	/* get word from tx buffer for sending */
+	void (*tx_word) (struct sirfsoc_spi *);
+
+	/* number of words left to be tranmitted/received */
+	unsigned int left_tx_word;
+	unsigned int left_rx_word;
+
+	/* rx & tx DMA channels */
+	struct dma_chan *rx_chan;
+	struct dma_chan *tx_chan;
+	dma_addr_t src_start;
+	dma_addr_t dst_start;
+	void *dummypage;
+	int word_width; /* in bytes */
+
+	/*
+	 * if tx size is not more than 4 and rx size is NULL, use
+	 * command model
+	 */
+	bool	tx_by_cmd;
+	bool	hw_cs;
+};
+
+static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
+{
+	u32 data;
+	u8 *rx = sspi->rx;
+
+	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+	if (rx) {
+		*rx++ = (u8) data;
+		sspi->rx = rx;
+	}
+
+	sspi->left_rx_word--;
+}
+
+static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
+{
+	u32 data = 0;
+	const u8 *tx = sspi->tx;
+
+	if (tx) {
+		data = *tx++;
+		sspi->tx = tx;
+	}
+
+	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+	sspi->left_tx_word--;
+}
+
+static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
+{
+	u32 data;
+	u16 *rx = sspi->rx;
+
+	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+	if (rx) {
+		*rx++ = (u16) data;
+		sspi->rx = rx;
+	}
+
+	sspi->left_rx_word--;
+}
+
+static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
+{
+	u32 data = 0;
+	const u16 *tx = sspi->tx;
+
+	if (tx) {
+		data = *tx++;
+		sspi->tx = tx;
+	}
+
+	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+	sspi->left_tx_word--;
+}
+
+static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
+{
+	u32 data;
+	u32 *rx = sspi->rx;
+
+	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
+
+	if (rx) {
+		*rx++ = (u32) data;
+		sspi->rx = rx;
+	}
+
+	sspi->left_rx_word--;
+
+}
+
+static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
+{
+	u32 data = 0;
+	const u32 *tx = sspi->tx;
+
+	if (tx) {
+		data = *tx++;
+		sspi->tx = tx;
+	}
+
+	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
+	sspi->left_tx_word--;
+}
+
+static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
+{
+	struct sirfsoc_spi *sspi = dev_id;
+	u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);
+	if (sspi->tx_by_cmd && (spi_stat & SIRFSOC_SPI_FRM_END)) {
+		complete(&sspi->tx_done);
+		writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+		writel(SIRFSOC_SPI_INT_MASK_ALL,
+				sspi->base + SIRFSOC_SPI_INT_STATUS);
+		return IRQ_HANDLED;
+	}
+
+	/* Error Conditions */
+	if (spi_stat & SIRFSOC_SPI_RX_OFLOW ||
+			spi_stat & SIRFSOC_SPI_TX_UFLOW) {
+		complete(&sspi->tx_done);
+		complete(&sspi->rx_done);
+		writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+		writel(SIRFSOC_SPI_INT_MASK_ALL,
+				sspi->base + SIRFSOC_SPI_INT_STATUS);
+		return IRQ_HANDLED;
+	}
+	if (spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY)
+		complete(&sspi->tx_done);
+	while (!(readl(sspi->base + SIRFSOC_SPI_INT_STATUS) &
+		SIRFSOC_SPI_RX_IO_DMA))
+		cpu_relax();
+	complete(&sspi->rx_done);
+	writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
+	writel(SIRFSOC_SPI_INT_MASK_ALL,
+			sspi->base + SIRFSOC_SPI_INT_STATUS);
+
+	return IRQ_HANDLED;
+}
+
+static void spi_sirfsoc_dma_fini_callback(void *data)
+{
+	struct completion *dma_complete = data;
+
+	complete(dma_complete);
+}
+
+static void spi_sirfsoc_cmd_transfer(struct spi_device *spi,
+	struct spi_transfer *t)
+{
+	struct sirfsoc_spi *sspi;
+	int timeout = t->len * 10;
+	u32 cmd;
+
+	sspi = spi_master_get_devdata(spi->master);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	memcpy(&cmd, sspi->tx, t->len);
+	if (sspi->word_width == 1 && !(spi->mode & SPI_LSB_FIRST))
+		cmd = cpu_to_be32(cmd) >>
+			((SIRFSOC_MAX_CMD_BYTES - t->len) * 8);
+	if (sspi->word_width == 2 && t->len == 4 &&
+			(!(spi->mode & SPI_LSB_FIRST)))
+		cmd = ((cmd & 0xffff) << 16) | (cmd >> 16);
+	writel(cmd, sspi->base + SIRFSOC_SPI_CMD);
+	writel(SIRFSOC_SPI_FRM_END_INT_EN,
+		sspi->base + SIRFSOC_SPI_INT_EN);
+	writel(SIRFSOC_SPI_CMD_TX_EN,
+		sspi->base + SIRFSOC_SPI_TX_RX_EN);
+	if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) {
+		dev_err(&spi->dev, "cmd transfer timeout\n");
+		return;
+	}
+	sspi->left_rx_word -= t->len;
+}
+
+static void spi_sirfsoc_dma_transfer(struct spi_device *spi,
+	struct spi_transfer *t)
+{
+	struct sirfsoc_spi *sspi;
+	struct dma_async_tx_descriptor *rx_desc, *tx_desc;
+	int timeout = t->len * 10;
+
+	sspi = spi_master_get_devdata(spi->master);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
+	writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
+	if (sspi->left_tx_word < SIRFSOC_SPI_DAT_FRM_LEN_MAX) {
+		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
+			SIRFSOC_SPI_ENA_AUTO_CLR | SIRFSOC_SPI_MUL_DAT_MODE,
+			sspi->base + SIRFSOC_SPI_CTRL);
+		writel(sspi->left_tx_word - 1,
+				sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+		writel(sspi->left_tx_word - 1,
+				sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+	} else {
+		writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
+			sspi->base + SIRFSOC_SPI_CTRL);
+		writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+		writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+	}
+	sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len,
+					(t->tx_buf != t->rx_buf) ?
+					DMA_FROM_DEVICE : DMA_BIDIRECTIONAL);
+	rx_desc = dmaengine_prep_slave_single(sspi->rx_chan,
+		sspi->dst_start, t->len, DMA_DEV_TO_MEM,
+		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	rx_desc->callback = spi_sirfsoc_dma_fini_callback;
+	rx_desc->callback_param = &sspi->rx_done;
+
+	sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len,
+					(t->tx_buf != t->rx_buf) ?
+					DMA_TO_DEVICE : DMA_BIDIRECTIONAL);
+	tx_desc = dmaengine_prep_slave_single(sspi->tx_chan,
+		sspi->src_start, t->len, DMA_MEM_TO_DEV,
+		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	tx_desc->callback = spi_sirfsoc_dma_fini_callback;
+	tx_desc->callback_param = &sspi->tx_done;
+
+	dmaengine_submit(tx_desc);
+	dmaengine_submit(rx_desc);
+	dma_async_issue_pending(sspi->tx_chan);
+	dma_async_issue_pending(sspi->rx_chan);
+	writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN,
+			sspi->base + SIRFSOC_SPI_TX_RX_EN);
+	if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0) {
+		dev_err(&spi->dev, "transfer timeout\n");
+		dmaengine_terminate_all(sspi->rx_chan);
+	} else
+		sspi->left_rx_word = 0;
+	/*
+	 * we only wait tx-done event if transferring by DMA. for PIO,
+	 * we get rx data by writing tx data, so if rx is done, tx has
+	 * done earlier
+	 */
+	if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) {
+		dev_err(&spi->dev, "transfer timeout\n");
+		dmaengine_terminate_all(sspi->tx_chan);
+	}
+	dma_unmap_single(&spi->dev, sspi->src_start, t->len, DMA_TO_DEVICE);
+	dma_unmap_single(&spi->dev, sspi->dst_start, t->len, DMA_FROM_DEVICE);
+	/* TX, RX FIFO stop */
+	writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	if (sspi->left_tx_word >= SIRFSOC_SPI_DAT_FRM_LEN_MAX)
+		writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
+}
+
+static void spi_sirfsoc_pio_transfer(struct spi_device *spi,
+		struct spi_transfer *t)
+{
+	struct sirfsoc_spi *sspi;
+	int timeout = t->len * 10;
+
+	sspi = spi_master_get_devdata(spi->master);
+	do {
+		writel(SIRFSOC_SPI_FIFO_RESET,
+			sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+		writel(SIRFSOC_SPI_FIFO_RESET,
+			sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+		writel(SIRFSOC_SPI_FIFO_START,
+			sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+		writel(SIRFSOC_SPI_FIFO_START,
+			sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+		writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
+		writel(SIRFSOC_SPI_INT_MASK_ALL,
+			sspi->base + SIRFSOC_SPI_INT_STATUS);
+		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
+			SIRFSOC_SPI_MUL_DAT_MODE | SIRFSOC_SPI_ENA_AUTO_CLR,
+			sspi->base + SIRFSOC_SPI_CTRL);
+		writel(min(sspi->left_tx_word, (u32)(256 / sspi->word_width))
+				- 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
+		writel(min(sspi->left_rx_word, (u32)(256 / sspi->word_width))
+				- 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
+		while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS)
+			& SIRFSOC_SPI_FIFO_FULL)) && sspi->left_tx_word)
+			sspi->tx_word(sspi);
+		writel(SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN |
+			SIRFSOC_SPI_TX_UFLOW_INT_EN |
+			SIRFSOC_SPI_RX_OFLOW_INT_EN |
+			SIRFSOC_SPI_RX_IO_DMA_INT_EN,
+			sspi->base + SIRFSOC_SPI_INT_EN);
+		writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN,
+			sspi->base + SIRFSOC_SPI_TX_RX_EN);
+		if (!wait_for_completion_timeout(&sspi->tx_done, timeout) ||
+			!wait_for_completion_timeout(&sspi->rx_done, timeout)) {
+			dev_err(&spi->dev, "transfer timeout\n");
+			break;
+		}
+		while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
+			& SIRFSOC_SPI_FIFO_EMPTY)) && sspi->left_rx_word)
+			sspi->rx_word(sspi);
+		writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+		writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	} while (sspi->left_tx_word != 0 || sspi->left_rx_word != 0);
+}
+
+static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct sirfsoc_spi *sspi;
+	sspi = spi_master_get_devdata(spi->master);
+
+	sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage;
+	sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage;
+	sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width;
+	reinit_completion(&sspi->rx_done);
+	reinit_completion(&sspi->tx_done);
+	/*
+	 * in the transfer, if transfer data using command register with rx_buf
+	 * null, just fill command data into command register and wait for its
+	 * completion.
+	 */
+	if (sspi->tx_by_cmd)
+		spi_sirfsoc_cmd_transfer(spi, t);
+	else if (IS_DMA_VALID(t))
+		spi_sirfsoc_dma_transfer(spi, t);
+	else
+		spi_sirfsoc_pio_transfer(spi, t);
+
+	return t->len - sspi->left_rx_word * sspi->word_width;
+}
+
+static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
+{
+	struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
+
+	if (sspi->hw_cs) {
+		u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
+		switch (value) {
+		case BITBANG_CS_ACTIVE:
+			if (spi->mode & SPI_CS_HIGH)
+				regval |= SIRFSOC_SPI_CS_IO_OUT;
+			else
+				regval &= ~SIRFSOC_SPI_CS_IO_OUT;
+			break;
+		case BITBANG_CS_INACTIVE:
+			if (spi->mode & SPI_CS_HIGH)
+				regval &= ~SIRFSOC_SPI_CS_IO_OUT;
+			else
+				regval |= SIRFSOC_SPI_CS_IO_OUT;
+			break;
+		}
+		writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
+	} else {
+		switch (value) {
+		case BITBANG_CS_ACTIVE:
+			gpio_direction_output(spi->cs_gpio,
+					spi->mode & SPI_CS_HIGH ? 1 : 0);
+			break;
+		case BITBANG_CS_INACTIVE:
+			gpio_direction_output(spi->cs_gpio,
+					spi->mode & SPI_CS_HIGH ? 0 : 1);
+			break;
+		}
+	}
+}
+
+static int
+spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
+{
+	struct sirfsoc_spi *sspi;
+	u8 bits_per_word = 0;
+	int hz = 0;
+	u32 regval;
+	u32 txfifo_ctrl, rxfifo_ctrl;
+	u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;
+
+	sspi = spi_master_get_devdata(spi->master);
+
+	bits_per_word = (t) ? t->bits_per_word : spi->bits_per_word;
+	hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
+
+	regval = (sspi->ctrl_freq / (2 * hz)) - 1;
+	if (regval > 0xFFFF || regval < 0) {
+		dev_err(&spi->dev, "Speed %d not supported\n", hz);
+		return -EINVAL;
+	}
+
+	switch (bits_per_word) {
+	case 8:
+		regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
+		sspi->rx_word = spi_sirfsoc_rx_word_u8;
+		sspi->tx_word = spi_sirfsoc_tx_word_u8;
+		break;
+	case 12:
+	case 16:
+		regval |= (bits_per_word ==  12) ?
+			SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
+			SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
+		sspi->rx_word = spi_sirfsoc_rx_word_u16;
+		sspi->tx_word = spi_sirfsoc_tx_word_u16;
+		break;
+	case 32:
+		regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
+		sspi->rx_word = spi_sirfsoc_rx_word_u32;
+		sspi->tx_word = spi_sirfsoc_tx_word_u32;
+		break;
+	default:
+		BUG();
+	}
+
+	sspi->word_width = DIV_ROUND_UP(bits_per_word, 8);
+	txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
+					   (sspi->word_width >> 1);
+	rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
+					   (sspi->word_width >> 1);
+
+	if (!(spi->mode & SPI_CS_HIGH))
+		regval |= SIRFSOC_SPI_CS_IDLE_STAT;
+	if (!(spi->mode & SPI_LSB_FIRST))
+		regval |= SIRFSOC_SPI_TRAN_MSB;
+	if (spi->mode & SPI_CPOL)
+		regval |= SIRFSOC_SPI_CLK_IDLE_STAT;
+
+	/*
+	 * Data should be driven at least 1/2 cycle before the fetch edge
+	 * to make sure that data gets stable at the fetch edge.
+	 */
+	if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
+	    (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
+		regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
+	else
+		regval |= SIRFSOC_SPI_DRV_POS_EDGE;
+
+	writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) |
+			SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
+			SIRFSOC_SPI_FIFO_HC(2),
+		sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
+	writel(SIRFSOC_SPI_FIFO_SC(2) |
+			SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
+			SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
+		sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
+	writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
+	writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);
+
+	if (t && t->tx_buf && !t->rx_buf && (t->len <= SIRFSOC_MAX_CMD_BYTES)) {
+		regval |= (SIRFSOC_SPI_CMD_BYTE_NUM((t->len - 1)) |
+				SIRFSOC_SPI_CMD_MODE);
+		sspi->tx_by_cmd = true;
+	} else {
+		regval &= ~SIRFSOC_SPI_CMD_MODE;
+		sspi->tx_by_cmd = false;
+	}
+	/*
+	 * it should never set to hardware cs mode because in hardware cs mode,
+	 * cs signal can't controlled by driver.
+	 */
+	regval |= SIRFSOC_SPI_CS_IO_MODE;
+	writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
+
+	if (IS_DMA_VALID(t)) {
+		/* Enable DMA mode for RX, TX */
+		writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
+		writel(SIRFSOC_SPI_RX_DMA_FLUSH,
+			sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
+	} else {
+		/* Enable IO mode for RX, TX */
+		writel(SIRFSOC_SPI_IO_MODE_SEL,
+			sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
+		writel(SIRFSOC_SPI_IO_MODE_SEL,
+			sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
+	}
+
+	return 0;
+}
+
+static int spi_sirfsoc_setup(struct spi_device *spi)
+{
+	struct sirfsoc_spi *sspi;
+
+	sspi = spi_master_get_devdata(spi->master);
+
+	if (spi->cs_gpio == -ENOENT)
+		sspi->hw_cs = true;
+	else
+		sspi->hw_cs = false;
+	return spi_sirfsoc_setup_transfer(spi, NULL);
+}
+
+static int spi_sirfsoc_probe(struct platform_device *pdev)
+{
+	struct sirfsoc_spi *sspi;
+	struct spi_master *master;
+	struct resource *mem_res;
+	int irq;
+	int i, ret;
+
+	ret = device_reset(&pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "SPI reset failed!\n");
+		return ret;
+	}
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*sspi));
+	if (!master) {
+		dev_err(&pdev->dev, "Unable to allocate SPI master\n");
+		return -ENOMEM;
+	}
+	platform_set_drvdata(pdev, master);
+	sspi = spi_master_get_devdata(master);
+
+	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	sspi->base = devm_ioremap_resource(&pdev->dev, mem_res);
+	if (IS_ERR(sspi->base)) {
+		ret = PTR_ERR(sspi->base);
+		goto free_master;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = -ENXIO;
+		goto free_master;
+	}
+	ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
+				DRIVER_NAME, sspi);
+	if (ret)
+		goto free_master;
+
+	sspi->bitbang.master = master;
+	sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
+	sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
+	sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
+	sspi->bitbang.master->setup = spi_sirfsoc_setup;
+	master->bus_num = pdev->id;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH;
+	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(12) |
+					SPI_BPW_MASK(16) | SPI_BPW_MASK(32);
+	master->max_speed_hz = SIRFSOC_SPI_DEFAULT_FRQ;
+	sspi->bitbang.master->dev.of_node = pdev->dev.of_node;
+
+	/* request DMA channels */
+	sspi->rx_chan = dma_request_slave_channel(&pdev->dev, "rx");
+	if (!sspi->rx_chan) {
+		dev_err(&pdev->dev, "can not allocate rx dma channel\n");
+		ret = -ENODEV;
+		goto free_master;
+	}
+	sspi->tx_chan = dma_request_slave_channel(&pdev->dev, "tx");
+	if (!sspi->tx_chan) {
+		dev_err(&pdev->dev, "can not allocate tx dma channel\n");
+		ret = -ENODEV;
+		goto free_rx_dma;
+	}
+
+	sspi->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(sspi->clk)) {
+		ret = PTR_ERR(sspi->clk);
+		goto free_tx_dma;
+	}
+	clk_prepare_enable(sspi->clk);
+	sspi->ctrl_freq = clk_get_rate(sspi->clk);
+
+	init_completion(&sspi->rx_done);
+	init_completion(&sspi->tx_done);
+
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	/* We are not using dummy delay between command and data */
+	writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);
+
+	sspi->dummypage = kmalloc(2 * PAGE_SIZE, GFP_KERNEL);
+	if (!sspi->dummypage) {
+		ret = -ENOMEM;
+		goto free_clk;
+	}
+
+	ret = spi_bitbang_start(&sspi->bitbang);
+	if (ret)
+		goto free_dummypage;
+	for (i = 0; master->cs_gpios && i < master->num_chipselect; i++) {
+		if (master->cs_gpios[i] == -ENOENT)
+			continue;
+		if (!gpio_is_valid(master->cs_gpios[i])) {
+			dev_err(&pdev->dev, "no valid gpio\n");
+			ret = -EINVAL;
+			goto free_dummypage;
+		}
+		ret = devm_gpio_request(&pdev->dev,
+				master->cs_gpios[i], DRIVER_NAME);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to request gpio\n");
+			goto free_dummypage;
+		}
+	}
+	dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);
+
+	return 0;
+free_dummypage:
+	kfree(sspi->dummypage);
+free_clk:
+	clk_disable_unprepare(sspi->clk);
+	clk_put(sspi->clk);
+free_tx_dma:
+	dma_release_channel(sspi->tx_chan);
+free_rx_dma:
+	dma_release_channel(sspi->rx_chan);
+free_master:
+	spi_master_put(master);
+
+	return ret;
+}
+
+static int  spi_sirfsoc_remove(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct sirfsoc_spi *sspi;
+
+	master = platform_get_drvdata(pdev);
+	sspi = spi_master_get_devdata(master);
+
+	spi_bitbang_stop(&sspi->bitbang);
+	kfree(sspi->dummypage);
+	clk_disable_unprepare(sspi->clk);
+	clk_put(sspi->clk);
+	dma_release_channel(sspi->rx_chan);
+	dma_release_channel(sspi->tx_chan);
+	spi_master_put(master);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int spi_sirfsoc_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = spi_master_suspend(master);
+	if (ret)
+		return ret;
+
+	clk_disable(sspi->clk);
+	return 0;
+}
+
+static int spi_sirfsoc_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
+
+	clk_enable(sspi->clk);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
+	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
+
+	return spi_master_resume(master);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(spi_sirfsoc_pm_ops, spi_sirfsoc_suspend,
+			 spi_sirfsoc_resume);
+
+static const struct of_device_id spi_sirfsoc_of_match[] = {
+	{ .compatible = "sirf,prima2-spi", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, spi_sirfsoc_of_match);
+
+static struct platform_driver spi_sirfsoc_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.pm     = &spi_sirfsoc_pm_ops,
+		.of_match_table = spi_sirfsoc_of_match,
+	},
+	.probe = spi_sirfsoc_probe,
+	.remove = spi_sirfsoc_remove,
+};
+module_platform_driver(spi_sirfsoc_driver);
+MODULE_DESCRIPTION("SiRF SoC SPI master driver");
+MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>");
+MODULE_AUTHOR("Barry Song <Baohua.Song@csr.com>");
+MODULE_LICENSE("GPL v2");