Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1480 insertions, 0 deletions

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
new file mode 100644
index 000000000..1d948fee1
--- /dev/null
+++ b/drivers/spi/spi-s3c64xx.c
@@ -0,0 +1,1480 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (c) 2009 Samsung Electronics Co., Ltd.
+//      Jaswinder Singh <jassi.brar@samsung.com>
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+
+#include <linux/platform_data/spi-s3c64xx.h>
+
+#define MAX_SPI_PORTS		6
+#define S3C64XX_SPI_QUIRK_POLL		(1 << 0)
+#define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
+#define AUTOSUSPEND_TIMEOUT	2000
+
+/* Registers and bit-fields */
+
+#define S3C64XX_SPI_CH_CFG		0x00
+#define S3C64XX_SPI_CLK_CFG		0x04
+#define S3C64XX_SPI_MODE_CFG		0x08
+#define S3C64XX_SPI_SLAVE_SEL		0x0C
+#define S3C64XX_SPI_INT_EN		0x10
+#define S3C64XX_SPI_STATUS		0x14
+#define S3C64XX_SPI_TX_DATA		0x18
+#define S3C64XX_SPI_RX_DATA		0x1C
+#define S3C64XX_SPI_PACKET_CNT		0x20
+#define S3C64XX_SPI_PENDING_CLR		0x24
+#define S3C64XX_SPI_SWAP_CFG		0x28
+#define S3C64XX_SPI_FB_CLK		0x2C
+
+#define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
+#define S3C64XX_SPI_CH_SW_RST		(1<<5)
+#define S3C64XX_SPI_CH_SLAVE		(1<<4)
+#define S3C64XX_SPI_CPOL_L		(1<<3)
+#define S3C64XX_SPI_CPHA_B		(1<<2)
+#define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
+#define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
+
+#define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
+#define S3C64XX_SPI_CLKSEL_SRCSHFT	9
+#define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
+#define S3C64XX_SPI_PSR_MASK		0xff
+
+#define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
+#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
+#define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
+#define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
+#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
+#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
+#define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
+#define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
+#define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
+#define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
+#define S3C64XX_SPI_MODE_4BURST			(1<<0)
+
+#define S3C64XX_SPI_SLAVE_AUTO			(1<<1)
+#define S3C64XX_SPI_SLAVE_SIG_INACT		(1<<0)
+#define S3C64XX_SPI_SLAVE_NSC_CNT_2		(2<<4)
+
+#define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
+#define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
+#define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
+#define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
+#define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
+#define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
+#define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
+
+#define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
+#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR		(1<<4)
+#define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
+#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR		(1<<2)
+#define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
+#define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
+
+#define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
+
+#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
+#define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
+#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
+#define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
+#define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
+
+#define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
+#define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
+#define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
+#define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
+#define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
+#define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
+#define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
+#define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
+
+#define S3C64XX_SPI_FBCLK_MSK			(3<<0)
+
+#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
+#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
+				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
+#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i))
+#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \
+					FIFO_LVL_MASK(i))
+
+#define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
+#define S3C64XX_SPI_TRAILCNT_OFF	19
+
+#define S3C64XX_SPI_TRAILCNT		S3C64XX_SPI_MAX_TRAILCNT
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+#define is_polling(x)	(x->port_conf->quirks & S3C64XX_SPI_QUIRK_POLL)
+
+#define RXBUSY    (1<<2)
+#define TXBUSY    (1<<3)
+
+struct s3c64xx_spi_dma_data {
+	struct dma_chan *ch;
+	dma_cookie_t cookie;
+	enum dma_transfer_direction direction;
+};
+
+/**
+ * struct s3c64xx_spi_info - SPI Controller hardware info
+ * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
+ * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
+ * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
+ * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
+ * @clk_from_cmu: True, if the controller does not include a clock mux and
+ *	prescaler unit.
+ *
+ * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
+ * differ in some aspects such as the size of the fifo and spi bus clock
+ * setup. Such differences are specified to the driver using this structure
+ * which is provided as driver data to the driver.
+ */
+struct s3c64xx_spi_port_config {
+	int	fifo_lvl_mask[MAX_SPI_PORTS];
+	int	rx_lvl_offset;
+	int	tx_st_done;
+	int	quirks;
+	bool	high_speed;
+	bool	clk_from_cmu;
+	bool	clk_ioclk;
+};
+
+/**
+ * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
+ * @clk: Pointer to the spi clock.
+ * @src_clk: Pointer to the clock used to generate SPI signals.
+ * @ioclk: Pointer to the i/o clock between master and slave
+ * @master: Pointer to the SPI Protocol master.
+ * @cntrlr_info: Platform specific data for the controller this driver manages.
+ * @lock: Controller specific lock.
+ * @state: Set of FLAGS to indicate status.
+ * @rx_dmach: Controller's DMA channel for Rx.
+ * @tx_dmach: Controller's DMA channel for Tx.
+ * @sfr_start: BUS address of SPI controller regs.
+ * @regs: Pointer to ioremap'ed controller registers.
+ * @irq: interrupt
+ * @xfer_completion: To indicate completion of xfer task.
+ * @cur_mode: Stores the active configuration of the controller.
+ * @cur_bpw: Stores the active bits per word settings.
+ * @cur_speed: Stores the active xfer clock speed.
+ */
+struct s3c64xx_spi_driver_data {
+	void __iomem                    *regs;
+	struct clk                      *clk;
+	struct clk                      *src_clk;
+	struct clk                      *ioclk;
+	struct platform_device          *pdev;
+	struct spi_master               *master;
+	struct s3c64xx_spi_info  *cntrlr_info;
+	spinlock_t                      lock;
+	unsigned long                   sfr_start;
+	struct completion               xfer_completion;
+	unsigned                        state;
+	unsigned                        cur_mode, cur_bpw;
+	unsigned                        cur_speed;
+	struct s3c64xx_spi_dma_data	rx_dma;
+	struct s3c64xx_spi_dma_data	tx_dma;
+	struct s3c64xx_spi_port_config	*port_conf;
+	unsigned int			port_id;
+};
+
+static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
+{
+	void __iomem *regs = sdd->regs;
+	unsigned long loops;
+	u32 val;
+
+	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
+
+	val = readl(regs + S3C64XX_SPI_CH_CFG);
+	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
+	writel(val, regs + S3C64XX_SPI_CH_CFG);
+
+	val = readl(regs + S3C64XX_SPI_CH_CFG);
+	val |= S3C64XX_SPI_CH_SW_RST;
+	val &= ~S3C64XX_SPI_CH_HS_EN;
+	writel(val, regs + S3C64XX_SPI_CH_CFG);
+
+	/* Flush TxFIFO*/
+	loops = msecs_to_loops(1);
+	do {
+		val = readl(regs + S3C64XX_SPI_STATUS);
+	} while (TX_FIFO_LVL(val, sdd) && loops--);
+
+	if (loops == 0)
+		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
+
+	/* Flush RxFIFO*/
+	loops = msecs_to_loops(1);
+	do {
+		val = readl(regs + S3C64XX_SPI_STATUS);
+		if (RX_FIFO_LVL(val, sdd))
+			readl(regs + S3C64XX_SPI_RX_DATA);
+		else
+			break;
+	} while (loops--);
+
+	if (loops == 0)
+		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
+
+	val = readl(regs + S3C64XX_SPI_CH_CFG);
+	val &= ~S3C64XX_SPI_CH_SW_RST;
+	writel(val, regs + S3C64XX_SPI_CH_CFG);
+
+	val = readl(regs + S3C64XX_SPI_MODE_CFG);
+	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
+	writel(val, regs + S3C64XX_SPI_MODE_CFG);
+}
+
+static void s3c64xx_spi_dmacb(void *data)
+{
+	struct s3c64xx_spi_driver_data *sdd;
+	struct s3c64xx_spi_dma_data *dma = data;
+	unsigned long flags;
+
+	if (dma->direction == DMA_DEV_TO_MEM)
+		sdd = container_of(data,
+			struct s3c64xx_spi_driver_data, rx_dma);
+	else
+		sdd = container_of(data,
+			struct s3c64xx_spi_driver_data, tx_dma);
+
+	spin_lock_irqsave(&sdd->lock, flags);
+
+	if (dma->direction == DMA_DEV_TO_MEM) {
+		sdd->state &= ~RXBUSY;
+		if (!(sdd->state & TXBUSY))
+			complete(&sdd->xfer_completion);
+	} else {
+		sdd->state &= ~TXBUSY;
+		if (!(sdd->state & RXBUSY))
+			complete(&sdd->xfer_completion);
+	}
+
+	spin_unlock_irqrestore(&sdd->lock, flags);
+}
+
+static int prepare_dma(struct s3c64xx_spi_dma_data *dma,
+			struct sg_table *sgt)
+{
+	struct s3c64xx_spi_driver_data *sdd;
+	struct dma_slave_config config;
+	struct dma_async_tx_descriptor *desc;
+	int ret;
+
+	memset(&config, 0, sizeof(config));
+
+	if (dma->direction == DMA_DEV_TO_MEM) {
+		sdd = container_of((void *)dma,
+			struct s3c64xx_spi_driver_data, rx_dma);
+		config.direction = dma->direction;
+		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
+		config.src_addr_width = sdd->cur_bpw / 8;
+		config.src_maxburst = 1;
+		dmaengine_slave_config(dma->ch, &config);
+	} else {
+		sdd = container_of((void *)dma,
+			struct s3c64xx_spi_driver_data, tx_dma);
+		config.direction = dma->direction;
+		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
+		config.dst_addr_width = sdd->cur_bpw / 8;
+		config.dst_maxburst = 1;
+		dmaengine_slave_config(dma->ch, &config);
+	}
+
+	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
+				       dma->direction, DMA_PREP_INTERRUPT);
+	if (!desc) {
+		dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
+			dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
+		return -ENOMEM;
+	}
+
+	desc->callback = s3c64xx_spi_dmacb;
+	desc->callback_param = dma;
+
+	dma->cookie = dmaengine_submit(desc);
+	ret = dma_submit_error(dma->cookie);
+	if (ret) {
+		dev_err(&sdd->pdev->dev, "DMA submission failed");
+		return -EIO;
+	}
+
+	dma_async_issue_pending(dma->ch);
+	return 0;
+}
+
+static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct s3c64xx_spi_driver_data *sdd =
+					spi_master_get_devdata(spi->master);
+
+	if (sdd->cntrlr_info->no_cs)
+		return;
+
+	if (enable) {
+		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
+			writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+		} else {
+			u32 ssel = readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+
+			ssel |= (S3C64XX_SPI_SLAVE_AUTO |
+						S3C64XX_SPI_SLAVE_NSC_CNT_2);
+			writel(ssel, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+		}
+	} else {
+		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
+			writel(S3C64XX_SPI_SLAVE_SIG_INACT,
+			       sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+	}
+}
+
+static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
+{
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
+
+	if (is_polling(sdd))
+		return 0;
+
+	spi->dma_rx = sdd->rx_dma.ch;
+	spi->dma_tx = sdd->tx_dma.ch;
+
+	return 0;
+}
+
+static bool s3c64xx_spi_can_dma(struct spi_master *master,
+				struct spi_device *spi,
+				struct spi_transfer *xfer)
+{
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+	return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
+}
+
+static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
+				    struct spi_transfer *xfer, int dma_mode)
+{
+	void __iomem *regs = sdd->regs;
+	u32 modecfg, chcfg;
+	int ret = 0;
+
+	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
+	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
+
+	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
+	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
+
+	if (dma_mode) {
+		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
+	} else {
+		/* Always shift in data in FIFO, even if xfer is Tx only,
+		 * this helps setting PCKT_CNT value for generating clocks
+		 * as exactly needed.
+		 */
+		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
+		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
+					| S3C64XX_SPI_PACKET_CNT_EN,
+					regs + S3C64XX_SPI_PACKET_CNT);
+	}
+
+	if (xfer->tx_buf != NULL) {
+		sdd->state |= TXBUSY;
+		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
+		if (dma_mode) {
+			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
+			ret = prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
+		} else {
+			switch (sdd->cur_bpw) {
+			case 32:
+				iowrite32_rep(regs + S3C64XX_SPI_TX_DATA,
+					xfer->tx_buf, xfer->len / 4);
+				break;
+			case 16:
+				iowrite16_rep(regs + S3C64XX_SPI_TX_DATA,
+					xfer->tx_buf, xfer->len / 2);
+				break;
+			default:
+				iowrite8_rep(regs + S3C64XX_SPI_TX_DATA,
+					xfer->tx_buf, xfer->len);
+				break;
+			}
+		}
+	}
+
+	if (xfer->rx_buf != NULL) {
+		sdd->state |= RXBUSY;
+
+		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
+					&& !(sdd->cur_mode & SPI_CPHA))
+			chcfg |= S3C64XX_SPI_CH_HS_EN;
+
+		if (dma_mode) {
+			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
+			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
+			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
+					| S3C64XX_SPI_PACKET_CNT_EN,
+					regs + S3C64XX_SPI_PACKET_CNT);
+			ret = prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
+		}
+	}
+
+	if (ret)
+		return ret;
+
+	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
+	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
+
+	return 0;
+}
+
+static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
+					int timeout_ms)
+{
+	void __iomem *regs = sdd->regs;
+	unsigned long val = 1;
+	u32 status;
+
+	/* max fifo depth available */
+	u32 max_fifo = (FIFO_LVL_MASK(sdd) >> 1) + 1;
+
+	if (timeout_ms)
+		val = msecs_to_loops(timeout_ms);
+
+	do {
+		status = readl(regs + S3C64XX_SPI_STATUS);
+	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
+
+	/* return the actual received data length */
+	return RX_FIFO_LVL(status, sdd);
+}
+
+static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
+				struct spi_transfer *xfer)
+{
+	void __iomem *regs = sdd->regs;
+	unsigned long val;
+	u32 status;
+	int ms;
+
+	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
+	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
+	ms += 10; /* some tolerance */
+
+	val = msecs_to_jiffies(ms) + 10;
+	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
+
+	/*
+	 * If the previous xfer was completed within timeout, then
+	 * proceed further else return -EIO.
+	 * DmaTx returns after simply writing data in the FIFO,
+	 * w/o waiting for real transmission on the bus to finish.
+	 * DmaRx returns only after Dma read data from FIFO which
+	 * needs bus transmission to finish, so we don't worry if
+	 * Xfer involved Rx(with or without Tx).
+	 */
+	if (val && !xfer->rx_buf) {
+		val = msecs_to_loops(10);
+		status = readl(regs + S3C64XX_SPI_STATUS);
+		while ((TX_FIFO_LVL(status, sdd)
+			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
+		       && --val) {
+			cpu_relax();
+			status = readl(regs + S3C64XX_SPI_STATUS);
+		}
+
+	}
+
+	/* If timed out while checking rx/tx status return error */
+	if (!val)
+		return -EIO;
+
+	return 0;
+}
+
+static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
+				struct spi_transfer *xfer)
+{
+	void __iomem *regs = sdd->regs;
+	unsigned long val;
+	u32 status;
+	int loops;
+	u32 cpy_len;
+	u8 *buf;
+	int ms;
+
+	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
+	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
+	ms += 10; /* some tolerance */
+
+	val = msecs_to_loops(ms);
+	do {
+		status = readl(regs + S3C64XX_SPI_STATUS);
+	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
+
+	if (!val)
+		return -EIO;
+
+	/* If it was only Tx */
+	if (!xfer->rx_buf) {
+		sdd->state &= ~TXBUSY;
+		return 0;
+	}
+
+	/*
+	 * If the receive length is bigger than the controller fifo
+	 * size, calculate the loops and read the fifo as many times.
+	 * loops = length / max fifo size (calculated by using the
+	 * fifo mask).
+	 * For any size less than the fifo size the below code is
+	 * executed atleast once.
+	 */
+	loops = xfer->len / ((FIFO_LVL_MASK(sdd) >> 1) + 1);
+	buf = xfer->rx_buf;
+	do {
+		/* wait for data to be received in the fifo */
+		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
+						       (loops ? ms : 0));
+
+		switch (sdd->cur_bpw) {
+		case 32:
+			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
+				     buf, cpy_len / 4);
+			break;
+		case 16:
+			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
+				     buf, cpy_len / 2);
+			break;
+		default:
+			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
+				    buf, cpy_len);
+			break;
+		}
+
+		buf = buf + cpy_len;
+	} while (loops--);
+	sdd->state &= ~RXBUSY;
+
+	return 0;
+}
+
+static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
+{
+	void __iomem *regs = sdd->regs;
+	int ret;
+	u32 val;
+
+	/* Disable Clock */
+	if (!sdd->port_conf->clk_from_cmu) {
+		val = readl(regs + S3C64XX_SPI_CLK_CFG);
+		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
+		writel(val, regs + S3C64XX_SPI_CLK_CFG);
+	}
+
+	/* Set Polarity and Phase */
+	val = readl(regs + S3C64XX_SPI_CH_CFG);
+	val &= ~(S3C64XX_SPI_CH_SLAVE |
+			S3C64XX_SPI_CPOL_L |
+			S3C64XX_SPI_CPHA_B);
+
+	if (sdd->cur_mode & SPI_CPOL)
+		val |= S3C64XX_SPI_CPOL_L;
+
+	if (sdd->cur_mode & SPI_CPHA)
+		val |= S3C64XX_SPI_CPHA_B;
+
+	writel(val, regs + S3C64XX_SPI_CH_CFG);
+
+	/* Set Channel & DMA Mode */
+	val = readl(regs + S3C64XX_SPI_MODE_CFG);
+	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
+			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
+
+	switch (sdd->cur_bpw) {
+	case 32:
+		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
+		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
+		break;
+	case 16:
+		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
+		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
+		break;
+	default:
+		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
+		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
+		break;
+	}
+
+	writel(val, regs + S3C64XX_SPI_MODE_CFG);
+
+	if (sdd->port_conf->clk_from_cmu) {
+		/* The src_clk clock is divided internally by 2 */
+		ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
+		if (ret)
+			return ret;
+	} else {
+		/* Configure Clock */
+		val = readl(regs + S3C64XX_SPI_CLK_CFG);
+		val &= ~S3C64XX_SPI_PSR_MASK;
+		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
+				& S3C64XX_SPI_PSR_MASK);
+		writel(val, regs + S3C64XX_SPI_CLK_CFG);
+
+		/* Enable Clock */
+		val = readl(regs + S3C64XX_SPI_CLK_CFG);
+		val |= S3C64XX_SPI_ENCLK_ENABLE;
+		writel(val, regs + S3C64XX_SPI_CLK_CFG);
+	}
+
+	return 0;
+}
+
+#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
+
+static int s3c64xx_spi_prepare_message(struct spi_master *master,
+				       struct spi_message *msg)
+{
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+	struct spi_device *spi = msg->spi;
+	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
+
+	/* Configure feedback delay */
+	writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
+
+	return 0;
+}
+
+static int s3c64xx_spi_transfer_one(struct spi_master *master,
+				    struct spi_device *spi,
+				    struct spi_transfer *xfer)
+{
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+	const unsigned int fifo_len = (FIFO_LVL_MASK(sdd) >> 1) + 1;
+	const void *tx_buf = NULL;
+	void *rx_buf = NULL;
+	int target_len = 0, origin_len = 0;
+	int use_dma = 0;
+	int status;
+	u32 speed;
+	u8 bpw;
+	unsigned long flags;
+
+	reinit_completion(&sdd->xfer_completion);
+
+	/* Only BPW and Speed may change across transfers */
+	bpw = xfer->bits_per_word;
+	speed = xfer->speed_hz;
+
+	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
+		sdd->cur_bpw = bpw;
+		sdd->cur_speed = speed;
+		sdd->cur_mode = spi->mode;
+		status = s3c64xx_spi_config(sdd);
+		if (status)
+			return status;
+	}
+
+	if (!is_polling(sdd) && (xfer->len > fifo_len) &&
+	    sdd->rx_dma.ch && sdd->tx_dma.ch) {
+		use_dma = 1;
+
+	} else if (is_polling(sdd) && xfer->len > fifo_len) {
+		tx_buf = xfer->tx_buf;
+		rx_buf = xfer->rx_buf;
+		origin_len = xfer->len;
+
+		target_len = xfer->len;
+		if (xfer->len > fifo_len)
+			xfer->len = fifo_len;
+	}
+
+	do {
+		spin_lock_irqsave(&sdd->lock, flags);
+
+		/* Pending only which is to be done */
+		sdd->state &= ~RXBUSY;
+		sdd->state &= ~TXBUSY;
+
+		/* Start the signals */
+		s3c64xx_spi_set_cs(spi, true);
+
+		status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
+
+		spin_unlock_irqrestore(&sdd->lock, flags);
+
+		if (status) {
+			dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
+			break;
+		}
+
+		if (use_dma)
+			status = s3c64xx_wait_for_dma(sdd, xfer);
+		else
+			status = s3c64xx_wait_for_pio(sdd, xfer);
+
+		if (status) {
+			dev_err(&spi->dev,
+				"I/O Error: rx-%d tx-%d res:rx-%c tx-%c len-%d\n",
+				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
+				(sdd->state & RXBUSY) ? 'f' : 'p',
+				(sdd->state & TXBUSY) ? 'f' : 'p',
+				xfer->len);
+
+			if (use_dma) {
+				if (xfer->tx_buf && (sdd->state & TXBUSY))
+					dmaengine_terminate_all(sdd->tx_dma.ch);
+				if (xfer->rx_buf && (sdd->state & RXBUSY))
+					dmaengine_terminate_all(sdd->rx_dma.ch);
+			}
+		} else {
+			s3c64xx_flush_fifo(sdd);
+		}
+		if (target_len > 0) {
+			target_len -= xfer->len;
+
+			if (xfer->tx_buf)
+				xfer->tx_buf += xfer->len;
+
+			if (xfer->rx_buf)
+				xfer->rx_buf += xfer->len;
+
+			if (target_len > fifo_len)
+				xfer->len = fifo_len;
+			else
+				xfer->len = target_len;
+		}
+	} while (target_len > 0);
+
+	if (origin_len) {
+		/* Restore original xfer buffers and length */
+		xfer->tx_buf = tx_buf;
+		xfer->rx_buf = rx_buf;
+		xfer->len = origin_len;
+	}
+
+	return status;
+}
+
+static struct s3c64xx_spi_csinfo *s3c64xx_get_slave_ctrldata(
+				struct spi_device *spi)
+{
+	struct s3c64xx_spi_csinfo *cs;
+	struct device_node *slave_np, *data_np = NULL;
+	u32 fb_delay = 0;
+
+	slave_np = spi->dev.of_node;
+	if (!slave_np) {
+		dev_err(&spi->dev, "device node not found\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	data_np = of_get_child_by_name(slave_np, "controller-data");
+	if (!data_np) {
+		dev_err(&spi->dev, "child node 'controller-data' not found\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+	if (!cs) {
+		of_node_put(data_np);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
+	cs->fb_delay = fb_delay;
+	of_node_put(data_np);
+	return cs;
+}
+
+/*
+ * Here we only check the validity of requested configuration
+ * and save the configuration in a local data-structure.
+ * The controller is actually configured only just before we
+ * get a message to transfer.
+ */
+static int s3c64xx_spi_setup(struct spi_device *spi)
+{
+	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
+	struct s3c64xx_spi_driver_data *sdd;
+	int err;
+
+	sdd = spi_master_get_devdata(spi->master);
+	if (spi->dev.of_node) {
+		cs = s3c64xx_get_slave_ctrldata(spi);
+		spi->controller_data = cs;
+	} else if (cs) {
+		/* On non-DT platforms the SPI core will set spi->cs_gpio
+		 * to -ENOENT. The GPIO pin used to drive the chip select
+		 * is defined by using platform data so spi->cs_gpio value
+		 * has to be override to have the proper GPIO pin number.
+		 */
+		spi->cs_gpio = cs->line;
+	}
+
+	if (IS_ERR_OR_NULL(cs)) {
+		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi->chip_select);
+		return -ENODEV;
+	}
+
+	if (!spi_get_ctldata(spi)) {
+		if (gpio_is_valid(spi->cs_gpio)) {
+			err = gpio_request_one(spi->cs_gpio, GPIOF_OUT_INIT_HIGH,
+					       dev_name(&spi->dev));
+			if (err) {
+				dev_err(&spi->dev,
+					"Failed to get /CS gpio [%d]: %d\n",
+					spi->cs_gpio, err);
+				goto err_gpio_req;
+			}
+		}
+
+		spi_set_ctldata(spi, cs);
+	}
+
+	pm_runtime_get_sync(&sdd->pdev->dev);
+
+	/* Check if we can provide the requested rate */
+	if (!sdd->port_conf->clk_from_cmu) {
+		u32 psr, speed;
+
+		/* Max possible */
+		speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
+
+		if (spi->max_speed_hz > speed)
+			spi->max_speed_hz = speed;
+
+		psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
+		psr &= S3C64XX_SPI_PSR_MASK;
+		if (psr == S3C64XX_SPI_PSR_MASK)
+			psr--;
+
+		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
+		if (spi->max_speed_hz < speed) {
+			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
+				psr++;
+			} else {
+				err = -EINVAL;
+				goto setup_exit;
+			}
+		}
+
+		speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
+		if (spi->max_speed_hz >= speed) {
+			spi->max_speed_hz = speed;
+		} else {
+			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
+				spi->max_speed_hz);
+			err = -EINVAL;
+			goto setup_exit;
+		}
+	}
+
+	pm_runtime_mark_last_busy(&sdd->pdev->dev);
+	pm_runtime_put_autosuspend(&sdd->pdev->dev);
+	s3c64xx_spi_set_cs(spi, false);
+
+	return 0;
+
+setup_exit:
+	pm_runtime_mark_last_busy(&sdd->pdev->dev);
+	pm_runtime_put_autosuspend(&sdd->pdev->dev);
+	/* setup() returns with device de-selected */
+	s3c64xx_spi_set_cs(spi, false);
+
+	if (gpio_is_valid(spi->cs_gpio))
+		gpio_free(spi->cs_gpio);
+	spi_set_ctldata(spi, NULL);
+
+err_gpio_req:
+	if (spi->dev.of_node)
+		kfree(cs);
+
+	return err;
+}
+
+static void s3c64xx_spi_cleanup(struct spi_device *spi)
+{
+	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
+
+	if (gpio_is_valid(spi->cs_gpio)) {
+		gpio_free(spi->cs_gpio);
+		if (spi->dev.of_node)
+			kfree(cs);
+		else {
+			/* On non-DT platforms, the SPI core sets
+			 * spi->cs_gpio to -ENOENT and .setup()
+			 * overrides it with the GPIO pin value
+			 * passed using platform data.
+			 */
+			spi->cs_gpio = -ENOENT;
+		}
+	}
+
+	spi_set_ctldata(spi, NULL);
+}
+
+static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
+{
+	struct s3c64xx_spi_driver_data *sdd = data;
+	struct spi_master *spi = sdd->master;
+	unsigned int val, clr = 0;
+
+	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
+
+	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
+		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
+		dev_err(&spi->dev, "RX overrun\n");
+	}
+	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
+		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
+		dev_err(&spi->dev, "RX underrun\n");
+	}
+	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
+		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
+		dev_err(&spi->dev, "TX overrun\n");
+	}
+	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
+		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
+		dev_err(&spi->dev, "TX underrun\n");
+	}
+
+	/* Clear the pending irq by setting and then clearing it */
+	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
+	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
+
+	return IRQ_HANDLED;
+}
+
+static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
+{
+	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
+	void __iomem *regs = sdd->regs;
+	unsigned int val;
+
+	sdd->cur_speed = 0;
+
+	if (sci->no_cs)
+		writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+	else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
+		writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+
+	/* Disable Interrupts - we use Polling if not DMA mode */
+	writel(0, regs + S3C64XX_SPI_INT_EN);
+
+	if (!sdd->port_conf->clk_from_cmu)
+		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
+				regs + S3C64XX_SPI_CLK_CFG);
+	writel(0, regs + S3C64XX_SPI_MODE_CFG);
+	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
+
+	/* Clear any irq pending bits, should set and clear the bits */
+	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
+		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
+		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
+		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
+	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
+	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
+
+	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
+
+	val = readl(regs + S3C64XX_SPI_MODE_CFG);
+	val &= ~S3C64XX_SPI_MODE_4BURST;
+	val &= ~(S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
+	val |= (S3C64XX_SPI_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
+	writel(val, regs + S3C64XX_SPI_MODE_CFG);
+
+	s3c64xx_flush_fifo(sdd);
+}
+
+#ifdef CONFIG_OF
+static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
+{
+	struct s3c64xx_spi_info *sci;
+	u32 temp;
+
+	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
+	if (!sci)
+		return ERR_PTR(-ENOMEM);
+
+	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
+		dev_warn(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
+		sci->src_clk_nr = 0;
+	} else {
+		sci->src_clk_nr = temp;
+	}
+
+	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
+		dev_warn(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
+		sci->num_cs = 1;
+	} else {
+		sci->num_cs = temp;
+	}
+
+	sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
+
+	return sci;
+}
+#else
+static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
+{
+	return dev_get_platdata(dev);
+}
+#endif
+
+static const struct of_device_id s3c64xx_spi_dt_match[];
+
+static inline struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
+						struct platform_device *pdev)
+{
+#ifdef CONFIG_OF
+	if (pdev->dev.of_node) {
+		const struct of_device_id *match;
+		match = of_match_node(s3c64xx_spi_dt_match, pdev->dev.of_node);
+		return (struct s3c64xx_spi_port_config *)match->data;
+	}
+#endif
+	return (struct s3c64xx_spi_port_config *)
+			 platform_get_device_id(pdev)->driver_data;
+}
+
+static int s3c64xx_spi_probe(struct platform_device *pdev)
+{
+	struct resource	*mem_res;
+	struct s3c64xx_spi_driver_data *sdd;
+	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
+	struct spi_master *master;
+	int ret, irq;
+	char clk_name[16];
+
+	if (!sci && pdev->dev.of_node) {
+		sci = s3c64xx_spi_parse_dt(&pdev->dev);
+		if (IS_ERR(sci))
+			return PTR_ERR(sci);
+	}
+
+	if (!sci) {
+		dev_err(&pdev->dev, "platform_data missing!\n");
+		return -ENODEV;
+	}
+
+	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (mem_res == NULL) {
+		dev_err(&pdev->dev, "Unable to get SPI MEM resource\n");
+		return -ENXIO;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_warn(&pdev->dev, "Failed to get IRQ: %d\n", irq);
+		return irq;
+	}
+
+	master = spi_alloc_master(&pdev->dev,
+				sizeof(struct s3c64xx_spi_driver_data));
+	if (master == NULL) {
+		dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, master);
+
+	sdd = spi_master_get_devdata(master);
+	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
+	sdd->master = master;
+	sdd->cntrlr_info = sci;
+	sdd->pdev = pdev;
+	sdd->sfr_start = mem_res->start;
+	if (pdev->dev.of_node) {
+		ret = of_alias_get_id(pdev->dev.of_node, "spi");
+		if (ret < 0) {
+			dev_err(&pdev->dev, "failed to get alias id, errno %d\n",
+				ret);
+			goto err_deref_master;
+		}
+		sdd->port_id = ret;
+	} else {
+		sdd->port_id = pdev->id;
+	}
+
+	sdd->cur_bpw = 8;
+
+	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
+	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
+
+	master->dev.of_node = pdev->dev.of_node;
+	master->bus_num = sdd->port_id;
+	master->setup = s3c64xx_spi_setup;
+	master->cleanup = s3c64xx_spi_cleanup;
+	master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
+	master->prepare_message = s3c64xx_spi_prepare_message;
+	master->transfer_one = s3c64xx_spi_transfer_one;
+	master->num_chipselect = sci->num_cs;
+	master->dma_alignment = 8;
+	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
+					SPI_BPW_MASK(8);
+	/* the spi->mode bits understood by this driver: */
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+	master->auto_runtime_pm = true;
+	if (!is_polling(sdd))
+		master->can_dma = s3c64xx_spi_can_dma;
+
+	sdd->regs = devm_ioremap_resource(&pdev->dev, mem_res);
+	if (IS_ERR(sdd->regs)) {
+		ret = PTR_ERR(sdd->regs);
+		goto err_deref_master;
+	}
+
+	if (sci->cfg_gpio && sci->cfg_gpio()) {
+		dev_err(&pdev->dev, "Unable to config gpio\n");
+		ret = -EBUSY;
+		goto err_deref_master;
+	}
+
+	/* Setup clocks */
+	sdd->clk = devm_clk_get(&pdev->dev, "spi");
+	if (IS_ERR(sdd->clk)) {
+		dev_err(&pdev->dev, "Unable to acquire clock 'spi'\n");
+		ret = PTR_ERR(sdd->clk);
+		goto err_deref_master;
+	}
+
+	ret = clk_prepare_enable(sdd->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Couldn't enable clock 'spi'\n");
+		goto err_deref_master;
+	}
+
+	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
+	sdd->src_clk = devm_clk_get(&pdev->dev, clk_name);
+	if (IS_ERR(sdd->src_clk)) {
+		dev_err(&pdev->dev,
+			"Unable to acquire clock '%s'\n", clk_name);
+		ret = PTR_ERR(sdd->src_clk);
+		goto err_disable_clk;
+	}
+
+	ret = clk_prepare_enable(sdd->src_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Couldn't enable clock '%s'\n", clk_name);
+		goto err_disable_clk;
+	}
+
+	if (sdd->port_conf->clk_ioclk) {
+		sdd->ioclk = devm_clk_get(&pdev->dev, "spi_ioclk");
+		if (IS_ERR(sdd->ioclk)) {
+			dev_err(&pdev->dev, "Unable to acquire 'ioclk'\n");
+			ret = PTR_ERR(sdd->ioclk);
+			goto err_disable_src_clk;
+		}
+
+		ret = clk_prepare_enable(sdd->ioclk);
+		if (ret) {
+			dev_err(&pdev->dev, "Couldn't enable clock 'ioclk'\n");
+			goto err_disable_src_clk;
+		}
+	}
+
+	if (!is_polling(sdd)) {
+		/* Acquire DMA channels */
+		sdd->rx_dma.ch = dma_request_slave_channel_reason(&pdev->dev,
+								  "rx");
+		if (IS_ERR(sdd->rx_dma.ch)) {
+			dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
+			ret = PTR_ERR(sdd->rx_dma.ch);
+			goto err_disable_io_clk;
+		}
+		sdd->tx_dma.ch = dma_request_slave_channel_reason(&pdev->dev,
+								  "tx");
+		if (IS_ERR(sdd->tx_dma.ch)) {
+			dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
+			ret = PTR_ERR(sdd->tx_dma.ch);
+			goto err_release_rx_dma;
+		}
+	}
+
+	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	/* Setup Deufult Mode */
+	s3c64xx_spi_hwinit(sdd);
+
+	spin_lock_init(&sdd->lock);
+	init_completion(&sdd->xfer_completion);
+
+	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
+				"spi-s3c64xx", sdd);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
+			irq, ret);
+		goto err_pm_put;
+	}
+
+	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
+	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
+	       sdd->regs + S3C64XX_SPI_INT_EN);
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret != 0) {
+		dev_err(&pdev->dev, "cannot register SPI master: %d\n", ret);
+		goto err_pm_put;
+	}
+
+	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Slaves attached\n",
+					sdd->port_id, master->num_chipselect);
+	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
+					mem_res, (FIFO_LVL_MASK(sdd) >> 1) + 1);
+
+	pm_runtime_mark_last_busy(&pdev->dev);
+	pm_runtime_put_autosuspend(&pdev->dev);
+
+	return 0;
+
+err_pm_put:
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
+
+	if (!is_polling(sdd))
+		dma_release_channel(sdd->tx_dma.ch);
+err_release_rx_dma:
+	if (!is_polling(sdd))
+		dma_release_channel(sdd->rx_dma.ch);
+err_disable_io_clk:
+	clk_disable_unprepare(sdd->ioclk);
+err_disable_src_clk:
+	clk_disable_unprepare(sdd->src_clk);
+err_disable_clk:
+	clk_disable_unprepare(sdd->clk);
+err_deref_master:
+	spi_master_put(master);
+
+	return ret;
+}
+
+static int s3c64xx_spi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&pdev->dev);
+
+	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
+
+	if (!is_polling(sdd)) {
+		dma_release_channel(sdd->rx_dma.ch);
+		dma_release_channel(sdd->tx_dma.ch);
+	}
+
+	clk_disable_unprepare(sdd->ioclk);
+
+	clk_disable_unprepare(sdd->src_clk);
+
+	clk_disable_unprepare(sdd->clk);
+
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int s3c64xx_spi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+	int ret = spi_master_suspend(master);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_force_suspend(dev);
+	if (ret < 0)
+		return ret;
+
+	sdd->cur_speed = 0; /* Output Clock is stopped */
+
+	return 0;
+}
+
+static int s3c64xx_spi_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
+	int ret;
+
+	if (sci->cfg_gpio)
+		sci->cfg_gpio();
+
+	ret = pm_runtime_force_resume(dev);
+	if (ret < 0)
+		return ret;
+
+	return spi_master_resume(master);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int s3c64xx_spi_runtime_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+
+	clk_disable_unprepare(sdd->clk);
+	clk_disable_unprepare(sdd->src_clk);
+	clk_disable_unprepare(sdd->ioclk);
+
+	return 0;
+}
+
+static int s3c64xx_spi_runtime_resume(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
+	int ret;
+
+	if (sdd->port_conf->clk_ioclk) {
+		ret = clk_prepare_enable(sdd->ioclk);
+		if (ret != 0)
+			return ret;
+	}
+
+	ret = clk_prepare_enable(sdd->src_clk);
+	if (ret != 0)
+		goto err_disable_ioclk;
+
+	ret = clk_prepare_enable(sdd->clk);
+	if (ret != 0)
+		goto err_disable_src_clk;
+
+	s3c64xx_spi_hwinit(sdd);
+
+	return 0;
+
+err_disable_src_clk:
+	clk_disable_unprepare(sdd->src_clk);
+err_disable_ioclk:
+	clk_disable_unprepare(sdd->ioclk);
+
+	return ret;
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops s3c64xx_spi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
+	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
+			   s3c64xx_spi_runtime_resume, NULL)
+};
+
+static struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
+	.fifo_lvl_mask	= { 0x7f },
+	.rx_lvl_offset	= 13,
+	.tx_st_done	= 21,
+	.high_speed	= true,
+};
+
+static struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
+	.fifo_lvl_mask	= { 0x7f, 0x7F },
+	.rx_lvl_offset	= 13,
+	.tx_st_done	= 21,
+};
+
+static struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
+	.fifo_lvl_mask	= { 0x1ff, 0x7F },
+	.rx_lvl_offset	= 15,
+	.tx_st_done	= 25,
+	.high_speed	= true,
+};
+
+static struct s3c64xx_spi_port_config exynos4_spi_port_config = {
+	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
+	.rx_lvl_offset	= 15,
+	.tx_st_done	= 25,
+	.high_speed	= true,
+	.clk_from_cmu	= true,
+};
+
+static struct s3c64xx_spi_port_config exynos7_spi_port_config = {
+	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
+	.rx_lvl_offset	= 15,
+	.tx_st_done	= 25,
+	.high_speed	= true,
+	.clk_from_cmu	= true,
+	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
+	.fifo_lvl_mask	= { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
+	.rx_lvl_offset	= 15,
+	.tx_st_done	= 25,
+	.high_speed	= true,
+	.clk_from_cmu	= true,
+	.clk_ioclk	= true,
+	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
+	{
+		.name		= "s3c2443-spi",
+		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
+	}, {
+		.name		= "s3c6410-spi",
+		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
+	},
+	{ },
+};
+
+static const struct of_device_id s3c64xx_spi_dt_match[] = {
+	{ .compatible = "samsung,s3c2443-spi",
+			.data = (void *)&s3c2443_spi_port_config,
+	},
+	{ .compatible = "samsung,s3c6410-spi",
+			.data = (void *)&s3c6410_spi_port_config,
+	},
+	{ .compatible = "samsung,s5pv210-spi",
+			.data = (void *)&s5pv210_spi_port_config,
+	},
+	{ .compatible = "samsung,exynos4210-spi",
+			.data = (void *)&exynos4_spi_port_config,
+	},
+	{ .compatible = "samsung,exynos7-spi",
+			.data = (void *)&exynos7_spi_port_config,
+	},
+	{ .compatible = "samsung,exynos5433-spi",
+			.data = (void *)&exynos5433_spi_port_config,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
+
+static struct platform_driver s3c64xx_spi_driver = {
+	.driver = {
+		.name	= "s3c64xx-spi",
+		.pm = &s3c64xx_spi_pm,
+		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
+	},
+	.probe = s3c64xx_spi_probe,
+	.remove = s3c64xx_spi_remove,
+	.id_table = s3c64xx_spi_driver_ids,
+};
+MODULE_ALIAS("platform:s3c64xx-spi");
+
+module_platform_driver(s3c64xx_spi_driver);
+
+MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
+MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
+MODULE_LICENSE("GPL");