Merge remote-tracking branches 'spi/topic/delay', 'spi/topic/dw',...

Merge remote-tracking branches 'spi/topic/delay', 'spi/topic/dw', 'spi/topic/fsl-dspi' and 'spi/topic/fsl-espi' into spi-next

drivers/spi/Kconfig

@@ -380,7 +380,6 @@ config SPI_FSL_DSPI
 config SPI_FSL_ESPI
 	tristate "Freescale eSPI controller"
 	depends on FSL_SOC
-	select SPI_FSL_LIB
 	help
 	  This enables using the Freescale eSPI controllers in master mode.
 	  From MPC8536, 85xx platform uses the controller, and all P10xx,

drivers/spi/spi-dw.c

@@ -502,6 +502,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 	master->handle_err = dw_spi_handle_err;
 	master->max_speed_hz = dws->max_freq;
 	master->dev.of_node = dev->of_node;
+	master->flags = SPI_MASTER_GPIO_SS;
 
 	/* Basic HW init */
 	spi_hw_init(dev, dws);

drivers/spi/spi-fsl-dspi.c

@@ -15,6 +15,8 @@
 
 #include <linux/clk.h>
 #include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/interrupt.h>
@@ -40,6 +42,7 @@
 #define TRAN_STATE_WORD_ODD_NUM	0x04
 
 #define DSPI_FIFO_SIZE			4
+#define DSPI_DMA_BUFSIZE		(DSPI_FIFO_SIZE * 1024)
 
 #define SPI_MCR		0x00
 #define SPI_MCR_MASTER		(1 << 31)
@@ -72,6 +75,11 @@
 #define SPI_SR_TCFQF		0x80000000
 #define SPI_SR_CLEAR		0xdaad0000
 
+#define SPI_RSER_TFFFE		BIT(25)
+#define SPI_RSER_TFFFD		BIT(24)
+#define SPI_RSER_RFDFE		BIT(17)
+#define SPI_RSER_RFDFD		BIT(16)
+
 #define SPI_RSER		0x30
 #define SPI_RSER_EOQFE		0x10000000
 #define SPI_RSER_TCFQE		0x80000000
@@ -109,6 +117,8 @@
 
 #define SPI_TCR_TCNT_MAX	0x10000
 
+#define DMA_COMPLETION_TIMEOUT	msecs_to_jiffies(3000)
+
 struct chip_data {
 	u32 mcr_val;
 	u32 ctar_val;
@@ -118,6 +128,7 @@ struct chip_data {
 enum dspi_trans_mode {
 	DSPI_EOQ_MODE = 0,
 	DSPI_TCFQ_MODE,
+	DSPI_DMA_MODE,
 };
 
 struct fsl_dspi_devtype_data {
@@ -126,7 +137,7 @@ struct fsl_dspi_devtype_data {
 };
 
 static const struct fsl_dspi_devtype_data vf610_data = {
-	.trans_mode = DSPI_EOQ_MODE,
+	.trans_mode = DSPI_DMA_MODE,
 	.max_clock_factor = 2,
 };
 
@@ -140,6 +151,23 @@ static const struct fsl_dspi_devtype_data ls2085a_data = {
 	.max_clock_factor = 8,
 };
 
+struct fsl_dspi_dma {
+	/* Length of transfer in words of DSPI_FIFO_SIZE */
+	u32 curr_xfer_len;
+
+	u32 *tx_dma_buf;
+	struct dma_chan *chan_tx;
+	dma_addr_t tx_dma_phys;
+	struct completion cmd_tx_complete;
+	struct dma_async_tx_descriptor *tx_desc;
+
+	u32 *rx_dma_buf;
+	struct dma_chan *chan_rx;
+	dma_addr_t rx_dma_phys;
+	struct completion cmd_rx_complete;
+	struct dma_async_tx_descriptor *rx_desc;
+};
+
 struct fsl_dspi {
 	struct spi_master	*master;
 	struct platform_device	*pdev;
@@ -166,8 +194,11 @@ struct fsl_dspi {
 	u32			waitflags;
 
 	u32			spi_tcnt;
+	struct fsl_dspi_dma	*dma;
 };
 
+static u32 dspi_data_to_pushr(struct fsl_dspi *dspi, int tx_word);
+
 static inline int is_double_byte_mode(struct fsl_dspi *dspi)
 {
 	unsigned int val;
@@ -177,6 +208,255 @@ static inline int is_double_byte_mode(struct fsl_dspi *dspi)
 	return ((val & SPI_FRAME_BITS_MASK) == SPI_FRAME_BITS(8)) ? 0 : 1;
 }
 
+static void dspi_tx_dma_callback(void *arg)
+{
+	struct fsl_dspi *dspi = arg;
+	struct fsl_dspi_dma *dma = dspi->dma;
+
+	complete(&dma->cmd_tx_complete);
+}
+
+static void dspi_rx_dma_callback(void *arg)
+{
+	struct fsl_dspi *dspi = arg;
+	struct fsl_dspi_dma *dma = dspi->dma;
+	int rx_word;
+	int i;
+	u16 d;
+
+	rx_word = is_double_byte_mode(dspi);
+
+	if (!(dspi->dataflags & TRAN_STATE_RX_VOID)) {
+		for (i = 0; i < dma->curr_xfer_len; i++) {
+			d = dspi->dma->rx_dma_buf[i];
+			rx_word ? (*(u16 *)dspi->rx = d) :
+						(*(u8 *)dspi->rx = d);
+			dspi->rx += rx_word + 1;
+		}
+	}
+
+	complete(&dma->cmd_rx_complete);
+}
+
+static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
+{
+	struct fsl_dspi_dma *dma = dspi->dma;
+	struct device *dev = &dspi->pdev->dev;
+	int time_left;
+	int tx_word;
+	int i;
+
+	tx_word = is_double_byte_mode(dspi);
+
+	for (i = 0; i < dma->curr_xfer_len; i++) {
+		dspi->dma->tx_dma_buf[i] = dspi_data_to_pushr(dspi, tx_word);
+		if ((dspi->cs_change) && (!dspi->len))
+			dspi->dma->tx_dma_buf[i] &= ~SPI_PUSHR_CONT;
+	}
+
+	dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
+					dma->tx_dma_phys,
+					dma->curr_xfer_len *
+					DMA_SLAVE_BUSWIDTH_4_BYTES,
+					DMA_MEM_TO_DEV,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!dma->tx_desc) {
+		dev_err(dev, "Not able to get desc for DMA xfer\n");
+		return -EIO;
+	}
+
+	dma->tx_desc->callback = dspi_tx_dma_callback;
+	dma->tx_desc->callback_param = dspi;
+	if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
+		dev_err(dev, "DMA submit failed\n");
+		return -EINVAL;
+	}
+
+	dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
+					dma->rx_dma_phys,
+					dma->curr_xfer_len *
+					DMA_SLAVE_BUSWIDTH_4_BYTES,
+					DMA_DEV_TO_MEM,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!dma->rx_desc) {
+		dev_err(dev, "Not able to get desc for DMA xfer\n");
+		return -EIO;
+	}
+
+	dma->rx_desc->callback = dspi_rx_dma_callback;
+	dma->rx_desc->callback_param = dspi;
+	if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
+		dev_err(dev, "DMA submit failed\n");
+		return -EINVAL;
+	}
+
+	reinit_completion(&dspi->dma->cmd_rx_complete);
+	reinit_completion(&dspi->dma->cmd_tx_complete);
+
+	dma_async_issue_pending(dma->chan_rx);
+	dma_async_issue_pending(dma->chan_tx);
+
+	time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
+					DMA_COMPLETION_TIMEOUT);
+	if (time_left == 0) {
+		dev_err(dev, "DMA tx timeout\n");
+		dmaengine_terminate_all(dma->chan_tx);
+		dmaengine_terminate_all(dma->chan_rx);
+		return -ETIMEDOUT;
+	}
+
+	time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
+					DMA_COMPLETION_TIMEOUT);
+	if (time_left == 0) {
+		dev_err(dev, "DMA rx timeout\n");
+		dmaengine_terminate_all(dma->chan_tx);
+		dmaengine_terminate_all(dma->chan_rx);
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int dspi_dma_xfer(struct fsl_dspi *dspi)
+{
+	struct fsl_dspi_dma *dma = dspi->dma;
+	struct device *dev = &dspi->pdev->dev;
+	int curr_remaining_bytes;
+	int bytes_per_buffer;
+	int word = 1;
+	int ret = 0;
+
+	if (is_double_byte_mode(dspi))
+		word = 2;
+	curr_remaining_bytes = dspi->len;
+	bytes_per_buffer = DSPI_DMA_BUFSIZE / DSPI_FIFO_SIZE;
+	while (curr_remaining_bytes) {
+		/* Check if current transfer fits the DMA buffer */
+		dma->curr_xfer_len = curr_remaining_bytes / word;
+		if (dma->curr_xfer_len > bytes_per_buffer)
+			dma->curr_xfer_len = bytes_per_buffer;
+
+		ret = dspi_next_xfer_dma_submit(dspi);
+		if (ret) {
+			dev_err(dev, "DMA transfer failed\n");
+			goto exit;
+
+		} else {
+			curr_remaining_bytes -= dma->curr_xfer_len * word;
+			if (curr_remaining_bytes < 0)
+				curr_remaining_bytes = 0;
+		}
+	}
+
+exit:
+	return ret;
+}
+
+static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
+{
+	struct fsl_dspi_dma *dma;
+	struct dma_slave_config cfg;
+	struct device *dev = &dspi->pdev->dev;
+	int ret;
+
+	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
+	if (!dma)
+		return -ENOMEM;
+
+	dma->chan_rx = dma_request_slave_channel(dev, "rx");
+	if (!dma->chan_rx) {
+		dev_err(dev, "rx dma channel not available\n");
+		ret = -ENODEV;
+		return ret;
+	}
+
+	dma->chan_tx = dma_request_slave_channel(dev, "tx");
+	if (!dma->chan_tx) {
+		dev_err(dev, "tx dma channel not available\n");
+		ret = -ENODEV;
+		goto err_tx_channel;
+	}
+
+	dma->tx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
+					&dma->tx_dma_phys, GFP_KERNEL);
+	if (!dma->tx_dma_buf) {
+		ret = -ENOMEM;
+		goto err_tx_dma_buf;
+	}
+
+	dma->rx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
+					&dma->rx_dma_phys, GFP_KERNEL);
+	if (!dma->rx_dma_buf) {
+		ret = -ENOMEM;
+		goto err_rx_dma_buf;
+	}
+
+	cfg.src_addr = phy_addr + SPI_POPR;
+	cfg.dst_addr = phy_addr + SPI_PUSHR;
+	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.src_maxburst = 1;
+	cfg.dst_maxburst = 1;
+
+	cfg.direction = DMA_DEV_TO_MEM;
+	ret = dmaengine_slave_config(dma->chan_rx, &cfg);
+	if (ret) {
+		dev_err(dev, "can't configure rx dma channel\n");
+		ret = -EINVAL;
+		goto err_slave_config;
+	}
+
+	cfg.direction = DMA_MEM_TO_DEV;
+	ret = dmaengine_slave_config(dma->chan_tx, &cfg);
+	if (ret) {
+		dev_err(dev, "can't configure tx dma channel\n");
+		ret = -EINVAL;
+		goto err_slave_config;
+	}
+
+	dspi->dma = dma;
+	init_completion(&dma->cmd_tx_complete);
+	init_completion(&dma->cmd_rx_complete);
+
+	return 0;
+
+err_slave_config:
+	dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
+			dma->rx_dma_buf, dma->rx_dma_phys);
+err_rx_dma_buf:
+	dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
+			dma->tx_dma_buf, dma->tx_dma_phys);
+err_tx_dma_buf:
+	dma_release_channel(dma->chan_tx);
+err_tx_channel:
+	dma_release_channel(dma->chan_rx);
+
+	devm_kfree(dev, dma);
+	dspi->dma = NULL;
+
+	return ret;
+}
+
+static void dspi_release_dma(struct fsl_dspi *dspi)
+{
+	struct fsl_dspi_dma *dma = dspi->dma;
+	struct device *dev = &dspi->pdev->dev;
+
+	if (dma) {
+		if (dma->chan_tx) {
+			dma_unmap_single(dev, dma->tx_dma_phys,
+					DSPI_DMA_BUFSIZE, DMA_TO_DEVICE);
+			dma_release_channel(dma->chan_tx);
+		}
+
+		if (dma->chan_rx) {
+			dma_unmap_single(dev, dma->rx_dma_phys,
+					DSPI_DMA_BUFSIZE, DMA_FROM_DEVICE);
+			dma_release_channel(dma->chan_rx);
+		}
+	}
+}
+
 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
 		unsigned long clkrate)
 {
@@ -425,6 +705,12 @@ static int dspi_transfer_one_message(struct spi_master *master,
 			regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_TCFQE);
 			dspi_tcfq_write(dspi);
 			break;
+		case DSPI_DMA_MODE:
+			regmap_write(dspi->regmap, SPI_RSER,
+				SPI_RSER_TFFFE | SPI_RSER_TFFFD |
+				SPI_RSER_RFDFE | SPI_RSER_RFDFD);
+			status = dspi_dma_xfer(dspi);
+			break;
 		default:
 			dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
 				trans_mode);
@@ -432,9 +718,13 @@ static int dspi_transfer_one_message(struct spi_master *master,
 			goto out;
 		}
 
-		if (wait_event_interruptible(dspi->waitq, dspi->waitflags))
-			dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n");
+		if (trans_mode != DSPI_DMA_MODE) {
+			if (wait_event_interruptible(dspi->waitq,
+						dspi->waitflags))
+				dev_err(&dspi->pdev->dev,
+					"wait transfer complete fail!\n");
 			dspi->waitflags = 0;
+		}
 
 		if (transfer->delay_usecs)
 			udelay(transfer->delay_usecs);
@@ -740,6 +1030,13 @@ static int dspi_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_master_put;
 
+	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
+		if (dspi_request_dma(dspi, res->start)) {
+			dev_err(&pdev->dev, "can't get dma channels\n");
+			goto out_clk_put;
+		}
+	}
+
 	master->max_speed_hz =
 		clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
 
@@ -768,6 +1065,7 @@ static int dspi_remove(struct platform_device *pdev)
 	struct fsl_dspi *dspi = spi_master_get_devdata(master);
 
 	/* Disconnect from the SPI framework */
+	dspi_release_dma(dspi);
 	clk_disable_unprepare(dspi->clk);
 	spi_unregister_master(dspi->master);
 

drivers/spi/spi-fsl-espi.c

@@ -23,8 +23,6 @@
 #include <linux/pm_runtime.h>
 #include <sysdev/fsl_soc.h>
 
-#include "spi-fsl-lib.h"
-
 /* eSPI Controller registers */
 #define ESPI_SPMODE	0x00	/* eSPI mode register */
 #define ESPI_SPIE	0x04	/* eSPI event register */
@@ -54,8 +52,11 @@
 #define CSMODE_AFT(x)		((x) << 8)
 #define CSMODE_CG(x)		((x) << 3)
 
+#define FSL_ESPI_FIFO_SIZE	32
+#define FSL_ESPI_RXTHR		15
+
 /* Default mode/csmode for eSPI controller */
-#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
+#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(FSL_ESPI_RXTHR))
 #define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
 		| CSMODE_AFT(0) | CSMODE_CG(1))
 
@@ -90,219 +91,342 @@
 
 #define AUTOSUSPEND_TIMEOUT 2000
 
-static inline u32 fsl_espi_read_reg(struct mpc8xxx_spi *mspi, int offset)
+struct fsl_espi {
+	struct device *dev;
+	void __iomem *reg_base;
+
+	struct list_head *m_transfers;
+	struct spi_transfer *tx_t;
+	unsigned int tx_pos;
+	bool tx_done;
+	struct spi_transfer *rx_t;
+	unsigned int rx_pos;
+	bool rx_done;
+
+	bool swab;
+	unsigned int rxskip;
+
+	spinlock_t lock;
+
+	u32 spibrg;             /* SPIBRG input clock */
+
+	struct completion done;
+};
+
+struct fsl_espi_cs {
+	u32 hw_mode;
+};
+
+static inline u32 fsl_espi_read_reg(struct fsl_espi *espi, int offset)
 {
-	return ioread32be(mspi->reg_base + offset);
+	return ioread32be(espi->reg_base + offset);
 }
 
-static inline u8 fsl_espi_read_reg8(struct mpc8xxx_spi *mspi, int offset)
+static inline u16 fsl_espi_read_reg16(struct fsl_espi *espi, int offset)
 {
-	return ioread8(mspi->reg_base + offset);
+	return ioread16be(espi->reg_base + offset);
 }
 
-static inline void fsl_espi_write_reg(struct mpc8xxx_spi *mspi, int offset,
-				      u32 val)
+static inline u8 fsl_espi_read_reg8(struct fsl_espi *espi, int offset)
 {
-	iowrite32be(val, mspi->reg_base + offset);
+	return ioread8(espi->reg_base + offset);
 }
 
-static inline void fsl_espi_write_reg8(struct mpc8xxx_spi *mspi, int offset,
-				       u8 val)
+static inline void fsl_espi_write_reg(struct fsl_espi *espi, int offset,
+				      u32 val)
 {
-	iowrite8(val, mspi->reg_base + offset);
+	iowrite32be(val, espi->reg_base + offset);
 }
 
-static void fsl_espi_copy_to_buf(struct spi_message *m,
-				 struct mpc8xxx_spi *mspi)
+static inline void fsl_espi_write_reg16(struct fsl_espi *espi, int offset,
+					u16 val)
 {
-	struct spi_transfer *t;
-	u8 *buf = mspi->local_buf;
-
-	list_for_each_entry(t, &m->transfers, transfer_list) {
-		if (t->tx_buf)
-			memcpy(buf, t->tx_buf, t->len);
-		else
-			memset(buf, 0, t->len);
-		buf += t->len;
-	}
+	iowrite16be(val, espi->reg_base + offset);
 }
 
-static void fsl_espi_copy_from_buf(struct spi_message *m,
-				   struct mpc8xxx_spi *mspi)
+static inline void fsl_espi_write_reg8(struct fsl_espi *espi, int offset,
+				       u8 val)
 {
-	struct spi_transfer *t;
-	u8 *buf = mspi->local_buf;
-
-	list_for_each_entry(t, &m->transfers, transfer_list) {
-		if (t->rx_buf)
-			memcpy(t->rx_buf, buf, t->len);
-		buf += t->len;
-	}
+	iowrite8(val, espi->reg_base + offset);
 }
 
 static int fsl_espi_check_message(struct spi_message *m)
 {
-	struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
+	struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
 	struct spi_transfer *t, *first;
 
 	if (m->frame_length > SPCOM_TRANLEN_MAX) {
-		dev_err(mspi->dev, "message too long, size is %u bytes\n",
+		dev_err(espi->dev, "message too long, size is %u bytes\n",
 			m->frame_length);
 		return -EMSGSIZE;
 	}
 
 	first = list_first_entry(&m->transfers, struct spi_transfer,
 				 transfer_list);
+
 	list_for_each_entry(t, &m->transfers, transfer_list) {
 		if (first->bits_per_word != t->bits_per_word ||
 		    first->speed_hz != t->speed_hz) {
-			dev_err(mspi->dev, "bits_per_word/speed_hz should be the same for all transfers\n");
+			dev_err(espi->dev, "bits_per_word/speed_hz should be the same for all transfers\n");
 			return -EINVAL;
 		}
 	}
 
+	/* ESPI supports MSB-first transfers for word size 8 / 16 only */
+	if (!(m->spi->mode & SPI_LSB_FIRST) && first->bits_per_word != 8 &&
+	    first->bits_per_word != 16) {
+		dev_err(espi->dev,
+			"MSB-first transfer not supported for wordsize %u\n",
+			first->bits_per_word);
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
-static void fsl_espi_change_mode(struct spi_device *spi)
+static unsigned int fsl_espi_check_rxskip_mode(struct spi_message *m)
 {
-	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
-	struct spi_mpc8xxx_cs *cs = spi->controller_state;
-	u32 tmp;
-	unsigned long flags;
-
-	/* Turn off IRQs locally to minimize time that SPI is disabled. */
-	local_irq_save(flags);
-
-	/* Turn off SPI unit prior changing mode */
-	tmp = fsl_espi_read_reg(mspi, ESPI_SPMODE);
-	fsl_espi_write_reg(mspi, ESPI_SPMODE, tmp & ~SPMODE_ENABLE);
-	fsl_espi_write_reg(mspi, ESPI_SPMODEx(spi->chip_select),
-			      cs->hw_mode);
-	fsl_espi_write_reg(mspi, ESPI_SPMODE, tmp);
+	struct spi_transfer *t;
+	unsigned int i = 0, rxskip = 0;
 
-	local_irq_restore(flags);
+	/*
+	 * prerequisites for ESPI rxskip mode:
+	 * - message has two transfers
+	 * - first transfer is a write and second is a read
+	 *
+	 * In addition the current low-level transfer mechanism requires
+	 * that the rxskip bytes fit into the TX FIFO. Else the transfer
+	 * would hang because after the first FSL_ESPI_FIFO_SIZE bytes
+	 * the TX FIFO isn't re-filled.
+	 */
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		if (i == 0) {
+			if (!t->tx_buf || t->rx_buf ||
+			    t->len > FSL_ESPI_FIFO_SIZE)
+				return 0;
+			rxskip = t->len;
+		} else if (i == 1) {
+			if (t->tx_buf || !t->rx_buf)
+				return 0;
+		}
+		i++;
+	}
+
+	return i == 2 ? rxskip : 0;
 }
 
-static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
+static void fsl_espi_fill_tx_fifo(struct fsl_espi *espi, u32 events)
 {
-	u32 data;
-	u16 data_h;
-	u16 data_l;
-	const u32 *tx = mpc8xxx_spi->tx;
+	u32 tx_fifo_avail;
+	unsigned int tx_left;
+	const void *tx_buf;
+
+	/* if events is zero transfer has not started and tx fifo is empty */
+	tx_fifo_avail = events ? SPIE_TXCNT(events) :  FSL_ESPI_FIFO_SIZE;
+start:
+	tx_left = espi->tx_t->len - espi->tx_pos;
+	tx_buf = espi->tx_t->tx_buf;
+	while (tx_fifo_avail >= min(4U, tx_left) && tx_left) {
+		if (tx_left >= 4) {
+			if (!tx_buf)
+				fsl_espi_write_reg(espi, ESPI_SPITF, 0);
+			else if (espi->swab)
+				fsl_espi_write_reg(espi, ESPI_SPITF,
+					swahb32p(tx_buf + espi->tx_pos));
+			else
+				fsl_espi_write_reg(espi, ESPI_SPITF,
+					*(u32 *)(tx_buf + espi->tx_pos));
+			espi->tx_pos += 4;
+			tx_left -= 4;
+			tx_fifo_avail -= 4;
+		} else if (tx_left >= 2 && tx_buf && espi->swab) {
+			fsl_espi_write_reg16(espi, ESPI_SPITF,
+					swab16p(tx_buf + espi->tx_pos));
+			espi->tx_pos += 2;
+			tx_left -= 2;
+			tx_fifo_avail -= 2;
+		} else {
+			if (!tx_buf)
+				fsl_espi_write_reg8(espi, ESPI_SPITF, 0);
+			else
+				fsl_espi_write_reg8(espi, ESPI_SPITF,
+					*(u8 *)(tx_buf + espi->tx_pos));
+			espi->tx_pos += 1;
+			tx_left -= 1;
+			tx_fifo_avail -= 1;
+		}
+	}
 
-	if (!tx)
-		return 0;
+	if (!tx_left) {
+		/* Last transfer finished, in rxskip mode only one is needed */
+		if (list_is_last(&espi->tx_t->transfer_list,
+		    espi->m_transfers) || espi->rxskip) {
+			espi->tx_done = true;
+			return;
+		}
+		espi->tx_t = list_next_entry(espi->tx_t, transfer_list);
+		espi->tx_pos = 0;
+		/* continue with next transfer if tx fifo is not full */
+		if (tx_fifo_avail)
+			goto start;
+	}
+}
+
+static void fsl_espi_read_rx_fifo(struct fsl_espi *espi, u32 events)
+{
+	u32 rx_fifo_avail = SPIE_RXCNT(events);
+	unsigned int rx_left;
+	void *rx_buf;
+
+start:
+	rx_left = espi->rx_t->len - espi->rx_pos;
+	rx_buf = espi->rx_t->rx_buf;
+	while (rx_fifo_avail >= min(4U, rx_left) && rx_left) {
+		if (rx_left >= 4) {
+			u32 val = fsl_espi_read_reg(espi, ESPI_SPIRF);
+
+			if (rx_buf && espi->swab)
+				*(u32 *)(rx_buf + espi->rx_pos) = swahb32(val);
+			else if (rx_buf)
+				*(u32 *)(rx_buf + espi->rx_pos) = val;
+			espi->rx_pos += 4;
+			rx_left -= 4;
+			rx_fifo_avail -= 4;
+		} else if (rx_left >= 2 && rx_buf && espi->swab) {
+			u16 val = fsl_espi_read_reg16(espi, ESPI_SPIRF);
+
+			*(u16 *)(rx_buf + espi->rx_pos) = swab16(val);
+			espi->rx_pos += 2;
+			rx_left -= 2;
+			rx_fifo_avail -= 2;
+		} else {
+			u8 val = fsl_espi_read_reg8(espi, ESPI_SPIRF);
 
-	data = *tx++ << mpc8xxx_spi->tx_shift;
-	data_l = data & 0xffff;
-	data_h = (data >> 16) & 0xffff;
-	swab16s(&data_l);
-	swab16s(&data_h);
-	data = data_h | data_l;
+			if (rx_buf)
+				*(u8 *)(rx_buf + espi->rx_pos) = val;
+			espi->rx_pos += 1;
+			rx_left -= 1;
+			rx_fifo_avail -= 1;
+		}
+	}
 
-	mpc8xxx_spi->tx = tx;
-	return data;
+	if (!rx_left) {
+		if (list_is_last(&espi->rx_t->transfer_list,
+		    espi->m_transfers)) {
+			espi->rx_done = true;
+			return;
+		}
+		espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
+		espi->rx_pos = 0;
+		/* continue with next transfer if rx fifo is not empty */
+		if (rx_fifo_avail)
+			goto start;
+	}
 }
 
 static void fsl_espi_setup_transfer(struct spi_device *spi,
 					struct spi_transfer *t)
 {
-	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	struct fsl_espi *espi = spi_master_get_devdata(spi->master);
 	int bits_per_word = t ? t->bits_per_word : spi->bits_per_word;
-	u32 hz = t ? t->speed_hz : spi->max_speed_hz;
-	u8 pm;
-	struct spi_mpc8xxx_cs *cs = spi->controller_state;
-
-	cs->rx_shift = 0;
-	cs->tx_shift = 0;
-	cs->get_rx = mpc8xxx_spi_rx_buf_u32;
-	cs->get_tx = mpc8xxx_spi_tx_buf_u32;
-	if (bits_per_word <= 8) {
-		cs->rx_shift = 8 - bits_per_word;
-	} else {
-		cs->rx_shift = 16 - bits_per_word;
-		if (spi->mode & SPI_LSB_FIRST)
-			cs->get_tx = fsl_espi_tx_buf_lsb;
-	}
-
-	mpc8xxx_spi->rx_shift = cs->rx_shift;
-	mpc8xxx_spi->tx_shift = cs->tx_shift;
-	mpc8xxx_spi->get_rx = cs->get_rx;
-	mpc8xxx_spi->get_tx = cs->get_tx;
+	u32 pm, hz = t ? t->speed_hz : spi->max_speed_hz;
+	struct fsl_espi_cs *cs = spi_get_ctldata(spi);
+	u32 hw_mode_old = cs->hw_mode;
 
 	/* mask out bits we are going to set */
 	cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
 
 	cs->hw_mode |= CSMODE_LEN(bits_per_word - 1);
 
-	if ((mpc8xxx_spi->spibrg / hz) > 64) {
-		cs->hw_mode |= CSMODE_DIV16;
-		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
+	pm = DIV_ROUND_UP(espi->spibrg, hz * 4) - 1;
 
-		WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. "
-			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
-				hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1)));
-		if (pm > 33)
-			pm = 33;
-	} else {
-		pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
+	if (pm > 15) {
+		cs->hw_mode |= CSMODE_DIV16;
+		pm = DIV_ROUND_UP(espi->spibrg, hz * 16 * 4) - 1;
 	}
-	if (pm)
-		pm--;
-	if (pm < 2)
-		pm = 2;
 
 	cs->hw_mode |= CSMODE_PM(pm);
 
-	fsl_espi_change_mode(spi);
+	/* don't write the mode register if the mode doesn't change */
+	if (cs->hw_mode != hw_mode_old)
+		fsl_espi_write_reg(espi, ESPI_SPMODEx(spi->chip_select),
+				   cs->hw_mode);
 }
 
 static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
 {
-	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
-	u32 word;
+	struct fsl_espi *espi = spi_master_get_devdata(spi->master);
+	unsigned int rx_len = t->len;
+	u32 mask, spcom;
 	int ret;
 
-	mpc8xxx_spi->len = t->len;
-	mpc8xxx_spi->count = roundup(t->len, 4) / 4;
-
-	mpc8xxx_spi->tx = t->tx_buf;
-	mpc8xxx_spi->rx = t->rx_buf;
-
-	reinit_completion(&mpc8xxx_spi->done);
+	reinit_completion(&espi->done);
 
 	/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM,
-		(SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
+	spcom = SPCOM_CS(spi->chip_select);
+	spcom |= SPCOM_TRANLEN(t->len - 1);
+
+	/* configure RXSKIP mode */
+	if (espi->rxskip) {
+		spcom |= SPCOM_RXSKIP(espi->rxskip);
+		rx_len = t->len - espi->rxskip;
+		if (t->rx_nbits == SPI_NBITS_DUAL)
+			spcom |= SPCOM_DO;
+	}
+
+	fsl_espi_write_reg(espi, ESPI_SPCOM, spcom);
 
-	/* enable rx ints */
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, SPIM_RNE);
+	/* enable interrupts */
+	mask = SPIM_DON;
+	if (rx_len > FSL_ESPI_FIFO_SIZE)
+		mask |= SPIM_RXT;
+	fsl_espi_write_reg(espi, ESPI_SPIM, mask);
 
-	/* transmit word */
-	word = mpc8xxx_spi->get_tx(mpc8xxx_spi);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPITF, word);
+	/* Prevent filling the fifo from getting interrupted */
+	spin_lock_irq(&espi->lock);
+	fsl_espi_fill_tx_fifo(espi, 0);
+	spin_unlock_irq(&espi->lock);
 
 	/* Won't hang up forever, SPI bus sometimes got lost interrupts... */
-	ret = wait_for_completion_timeout(&mpc8xxx_spi->done, 2 * HZ);
+	ret = wait_for_completion_timeout(&espi->done, 2 * HZ);
 	if (ret == 0)
-		dev_err(mpc8xxx_spi->dev,
-			"Transaction hanging up (left %d bytes)\n",
-			mpc8xxx_spi->count);
+		dev_err(espi->dev, "Transfer timed out!\n");
 
 	/* disable rx ints */
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
+	fsl_espi_write_reg(espi, ESPI_SPIM, 0);
 
-	return mpc8xxx_spi->count > 0 ? -EMSGSIZE : 0;
+	return ret == 0 ? -ETIMEDOUT : 0;
 }
 
 static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans)
 {
-	struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
+	struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
 	struct spi_device *spi = m->spi;
 	int ret;
 
-	fsl_espi_copy_to_buf(m, mspi);
+	/* In case of LSB-first and bits_per_word > 8 byte-swap all words */
+	espi->swab = spi->mode & SPI_LSB_FIRST && trans->bits_per_word > 8;
+
+	espi->m_transfers = &m->transfers;
+	espi->tx_t = list_first_entry(&m->transfers, struct spi_transfer,
+				      transfer_list);
+	espi->tx_pos = 0;
+	espi->tx_done = false;
+	espi->rx_t = list_first_entry(&m->transfers, struct spi_transfer,
+				      transfer_list);
+	espi->rx_pos = 0;
+	espi->rx_done = false;
+
+	espi->rxskip = fsl_espi_check_rxskip_mode(m);
+	if (trans->rx_nbits == SPI_NBITS_DUAL && !espi->rxskip) {
+		dev_err(espi->dev, "Dual output mode requires RXSKIP mode!\n");
+		return -EINVAL;
+	}
+
+	/* In RXSKIP mode skip first transfer for reads */
+	if (espi->rxskip)
+		espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
+
 	fsl_espi_setup_transfer(spi, trans);
 
 	ret = fsl_espi_bufs(spi, trans);
@@ -310,19 +434,13 @@ static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans)
 	if (trans->delay_usecs)
 		udelay(trans->delay_usecs);
 
-	fsl_espi_setup_transfer(spi, NULL);
-
-	if (!ret)
-		fsl_espi_copy_from_buf(m, mspi);
-
 	return ret;
 }
 
 static int fsl_espi_do_one_msg(struct spi_master *master,
 			       struct spi_message *m)
 {
-	struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
-	unsigned int delay_usecs = 0;
+	unsigned int delay_usecs = 0, rx_nbits = 0;
 	struct spi_transfer *t, trans = {};
 	int ret;
 
@@ -333,6 +451,8 @@ static int fsl_espi_do_one_msg(struct spi_master *master,
 	list_for_each_entry(t, &m->transfers, transfer_list) {
 		if (t->delay_usecs > delay_usecs)
 			delay_usecs = t->delay_usecs;
+		if (t->rx_nbits > rx_nbits)
+			rx_nbits = t->rx_nbits;
 	}
 
 	t = list_first_entry(&m->transfers, struct spi_transfer,
@@ -342,8 +462,7 @@ static int fsl_espi_do_one_msg(struct spi_master *master,
 	trans.speed_hz = t->speed_hz;
 	trans.bits_per_word = t->bits_per_word;
 	trans.delay_usecs = delay_usecs;
-	trans.tx_buf = mspi->local_buf;
-	trans.rx_buf = mspi->local_buf;
+	trans.rx_nbits = rx_nbits;
 
 	if (trans.len)
 		ret = fsl_espi_trans(m, &trans);
@@ -360,12 +479,9 @@ static int fsl_espi_do_one_msg(struct spi_master *master,
 
 static int fsl_espi_setup(struct spi_device *spi)
 {
-	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_espi *espi;
 	u32 loop_mode;
-	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
-
-	if (!spi->max_speed_hz)
-		return -EINVAL;
+	struct fsl_espi_cs *cs = spi_get_ctldata(spi);
 
 	if (!cs) {
 		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
@@ -374,12 +490,11 @@ static int fsl_espi_setup(struct spi_device *spi)
 		spi_set_ctldata(spi, cs);
 	}
 
-	mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	espi = spi_master_get_devdata(spi->master);
 
-	pm_runtime_get_sync(mpc8xxx_spi->dev);
+	pm_runtime_get_sync(espi->dev);
 
-	cs->hw_mode = fsl_espi_read_reg(mpc8xxx_spi,
-					   ESPI_SPMODEx(spi->chip_select));
+	cs->hw_mode = fsl_espi_read_reg(espi, ESPI_SPMODEx(spi->chip_select));
 	/* mask out bits we are going to set */
 	cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
 			 | CSMODE_REV);
@@ -392,115 +507,74 @@ static int fsl_espi_setup(struct spi_device *spi)
 		cs->hw_mode |= CSMODE_REV;
 
 	/* Handle the loop mode */
-	loop_mode = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
+	loop_mode = fsl_espi_read_reg(espi, ESPI_SPMODE);
 	loop_mode &= ~SPMODE_LOOP;
 	if (spi->mode & SPI_LOOP)
 		loop_mode |= SPMODE_LOOP;
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, loop_mode);
+	fsl_espi_write_reg(espi, ESPI_SPMODE, loop_mode);
 
 	fsl_espi_setup_transfer(spi, NULL);
 
-	pm_runtime_mark_last_busy(mpc8xxx_spi->dev);
-	pm_runtime_put_autosuspend(mpc8xxx_spi->dev);
+	pm_runtime_mark_last_busy(espi->dev);
+	pm_runtime_put_autosuspend(espi->dev);
 
 	return 0;
 }
 
 static void fsl_espi_cleanup(struct spi_device *spi)
 {
-	struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
+	struct fsl_espi_cs *cs = spi_get_ctldata(spi);
 
 	kfree(cs);
 	spi_set_ctldata(spi, NULL);
 }
 
-static void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
+static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events)
 {
-	/* We need handle RX first */
-	if (events & SPIE_RNE) {
-		u32 rx_data, tmp;
-		u8 rx_data_8;
-		int rx_nr_bytes = 4;
-		int ret;
-
-		/* Spin until RX is done */
-		if (SPIE_RXCNT(events) < min(4, mspi->len)) {
-			ret = spin_event_timeout(
-				!(SPIE_RXCNT(events =
-				fsl_espi_read_reg(mspi, ESPI_SPIE)) <
-						min(4, mspi->len)),
-						10000, 0); /* 10 msec */
-			if (!ret)
-				dev_err(mspi->dev,
-					 "tired waiting for SPIE_RXCNT\n");
-		}
+	if (!espi->rx_done)
+		fsl_espi_read_rx_fifo(espi, events);
 
-		if (mspi->len >= 4) {
-			rx_data = fsl_espi_read_reg(mspi, ESPI_SPIRF);
-		} else if (mspi->len <= 0) {
-			dev_err(mspi->dev,
-				"unexpected RX(SPIE_RNE) interrupt occurred,\n"
-				"(local rxlen %d bytes, reg rxlen %d bytes)\n",
-				min(4, mspi->len), SPIE_RXCNT(events));
-			rx_nr_bytes = 0;
-		} else {
-			rx_nr_bytes = mspi->len;
-			tmp = mspi->len;
-			rx_data = 0;
-			while (tmp--) {
-				rx_data_8 = fsl_espi_read_reg8(mspi,
-							       ESPI_SPIRF);
-				rx_data |= (rx_data_8 << (tmp * 8));
-			}
+	if (!espi->tx_done)
+		fsl_espi_fill_tx_fifo(espi, events);
 
-			rx_data <<= (4 - mspi->len) * 8;
-		}
-
-		mspi->len -= rx_nr_bytes;
-
-		if (rx_nr_bytes && mspi->rx)
-			mspi->get_rx(rx_data, mspi);
-	}
+	if (!espi->tx_done || !espi->rx_done)
+		return;
 
-	if (!(events & SPIE_TNF)) {
-		int ret;
+	/* we're done, but check for errors before returning */
+	events = fsl_espi_read_reg(espi, ESPI_SPIE);
 
-		/* spin until TX is done */
-		ret = spin_event_timeout(((events = fsl_espi_read_reg(
-				mspi, ESPI_SPIE)) & SPIE_TNF), 1000, 0);
-		if (!ret) {
-			dev_err(mspi->dev, "tired waiting for SPIE_TNF\n");
-			complete(&mspi->done);
-			return;
-		}
-	}
+	if (!(events & SPIE_DON))
+		dev_err(espi->dev,
+			"Transfer done but SPIE_DON isn't set!\n");
 
-	mspi->count -= 1;
-	if (mspi->count) {
-		u32 word = mspi->get_tx(mspi);
+	if (SPIE_RXCNT(events) || SPIE_TXCNT(events) != FSL_ESPI_FIFO_SIZE)
+		dev_err(espi->dev, "Transfer done but rx/tx fifo's aren't empty!\n");
 
-		fsl_espi_write_reg(mspi, ESPI_SPITF, word);
-	} else {
-		complete(&mspi->done);
-	}
+	complete(&espi->done);
 }
 
 static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
 {
-	struct mpc8xxx_spi *mspi = context_data;
+	struct fsl_espi *espi = context_data;
 	u32 events;
 
+	spin_lock(&espi->lock);
+
 	/* Get interrupt events(tx/rx) */
-	events = fsl_espi_read_reg(mspi, ESPI_SPIE);
-	if (!events)
+	events = fsl_espi_read_reg(espi, ESPI_SPIE);
+	if (!events) {
+		spin_unlock(&espi->lock);
 		return IRQ_NONE;
+	}
 
-	dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
+	dev_vdbg(espi->dev, "%s: events %x\n", __func__, events);
 
-	fsl_espi_cpu_irq(mspi, events);
+	fsl_espi_cpu_irq(espi, events);
 
 	/* Clear the events */
-	fsl_espi_write_reg(mspi, ESPI_SPIE, events);
+	fsl_espi_write_reg(espi, ESPI_SPIE, events);
+
+	spin_unlock(&espi->lock);
 
 	return IRQ_HANDLED;
 }
@@ -509,12 +583,12 @@ static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
 static int fsl_espi_runtime_suspend(struct device *dev)
 {
 	struct spi_master *master = dev_get_drvdata(dev);
-	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
+	struct fsl_espi *espi = spi_master_get_devdata(master);
 	u32 regval;
 
-	regval = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
+	regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
 	regval &= ~SPMODE_ENABLE;
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
+	fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
 
 	return 0;
 }
@@ -522,12 +596,12 @@ static int fsl_espi_runtime_suspend(struct device *dev)
 static int fsl_espi_runtime_resume(struct device *dev)
 {
 	struct spi_master *master = dev_get_drvdata(dev);
-	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
+	struct fsl_espi *espi = spi_master_get_devdata(master);
 	u32 regval;
 
-	regval = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
+	regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
 	regval |= SPMODE_ENABLE;
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
+	fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
 
 	return 0;
 }
@@ -538,96 +612,105 @@ static size_t fsl_espi_max_message_size(struct spi_device *spi)
 	return SPCOM_TRANLEN_MAX;
 }
 
+static void fsl_espi_init_regs(struct device *dev, bool initial)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct fsl_espi *espi = spi_master_get_devdata(master);
+	struct device_node *nc;
+	u32 csmode, cs, prop;
+	int ret;
+
+	/* SPI controller initializations */
+	fsl_espi_write_reg(espi, ESPI_SPMODE, 0);
+	fsl_espi_write_reg(espi, ESPI_SPIM, 0);
+	fsl_espi_write_reg(espi, ESPI_SPCOM, 0);
+	fsl_espi_write_reg(espi, ESPI_SPIE, 0xffffffff);
+
+	/* Init eSPI CS mode register */
+	for_each_available_child_of_node(master->dev.of_node, nc) {
+		/* get chip select */
+		ret = of_property_read_u32(nc, "reg", &cs);
+		if (ret || cs >= master->num_chipselect)
+			continue;
+
+		csmode = CSMODE_INIT_VAL;
+
+		/* check if CSBEF is set in device tree */
+		ret = of_property_read_u32(nc, "fsl,csbef", &prop);
+		if (!ret) {
+			csmode &= ~(CSMODE_BEF(0xf));
+			csmode |= CSMODE_BEF(prop);
+		}
+
+		/* check if CSAFT is set in device tree */
+		ret = of_property_read_u32(nc, "fsl,csaft", &prop);
+		if (!ret) {
+			csmode &= ~(CSMODE_AFT(0xf));
+			csmode |= CSMODE_AFT(prop);
+		}
+
+		fsl_espi_write_reg(espi, ESPI_SPMODEx(cs), csmode);
+
+		if (initial)
+			dev_info(dev, "cs=%u, init_csmode=0x%x\n", cs, csmode);
+	}
+
+	/* Enable SPI interface */
+	fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE);
+}
+
 static int fsl_espi_probe(struct device *dev, struct resource *mem,
-			  unsigned int irq)
+			  unsigned int irq, unsigned int num_cs)
 {
-	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
 	struct spi_master *master;
-	struct mpc8xxx_spi *mpc8xxx_spi;
-	struct device_node *nc;
-	const __be32 *prop;
-	u32 regval, csmode;
-	int i, len, ret;
+	struct fsl_espi *espi;
+	int ret;
 
-	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
+	master = spi_alloc_master(dev, sizeof(struct fsl_espi));
 	if (!master)
 		return -ENOMEM;
 
 	dev_set_drvdata(dev, master);
 
-	mpc8xxx_spi_probe(dev, mem, irq);
-
+	master->mode_bits = SPI_RX_DUAL | SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
+			    SPI_LSB_FIRST | SPI_LOOP;
+	master->dev.of_node = dev->of_node;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
 	master->setup = fsl_espi_setup;
 	master->cleanup = fsl_espi_cleanup;
 	master->transfer_one_message = fsl_espi_do_one_msg;
 	master->auto_runtime_pm = true;
 	master->max_message_size = fsl_espi_max_message_size;
+	master->num_chipselect = num_cs;
 
-	mpc8xxx_spi = spi_master_get_devdata(master);
+	espi = spi_master_get_devdata(master);
+	spin_lock_init(&espi->lock);
 
-	mpc8xxx_spi->local_buf =
-		devm_kmalloc(dev, SPCOM_TRANLEN_MAX, GFP_KERNEL);
-	if (!mpc8xxx_spi->local_buf) {
-		ret = -ENOMEM;
+	espi->dev = dev;
+	espi->spibrg = fsl_get_sys_freq();
+	if (espi->spibrg == -1) {
+		dev_err(dev, "Can't get sys frequency!\n");
+		ret = -EINVAL;
 		goto err_probe;
 	}
+	/* determined by clock divider fields DIV16/PM in register SPMODEx */
+	master->min_speed_hz = DIV_ROUND_UP(espi->spibrg, 4 * 16 * 16);
+	master->max_speed_hz = DIV_ROUND_UP(espi->spibrg, 4);
+
+	init_completion(&espi->done);
 
-	mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
-	if (IS_ERR(mpc8xxx_spi->reg_base)) {
-		ret = PTR_ERR(mpc8xxx_spi->reg_base);
+	espi->reg_base = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(espi->reg_base)) {
+		ret = PTR_ERR(espi->reg_base);
 		goto err_probe;
 	}
 
 	/* Register for SPI Interrupt */
-	ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_espi_irq,
-			  0, "fsl_espi", mpc8xxx_spi);
+	ret = devm_request_irq(dev, irq, fsl_espi_irq, 0, "fsl_espi", espi);
 	if (ret)
 		goto err_probe;
 
-	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
-		mpc8xxx_spi->rx_shift = 16;
-		mpc8xxx_spi->tx_shift = 24;
-	}
-
-	/* SPI controller initializations */
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIE, 0xffffffff);
-
-	/* Init eSPI CS mode register */
-	for_each_available_child_of_node(master->dev.of_node, nc) {
-		/* get chip select */
-		prop = of_get_property(nc, "reg", &len);
-		if (!prop || len < sizeof(*prop))
-			continue;
-		i = be32_to_cpup(prop);
-		if (i < 0 || i >= pdata->max_chipselect)
-			continue;
-
-		csmode = CSMODE_INIT_VAL;
-		/* check if CSBEF is set in device tree */
-		prop = of_get_property(nc, "fsl,csbef", &len);
-		if (prop && len >= sizeof(*prop)) {
-			csmode &= ~(CSMODE_BEF(0xf));
-			csmode |= CSMODE_BEF(be32_to_cpup(prop));
-		}
-		/* check if CSAFT is set in device tree */
-		prop = of_get_property(nc, "fsl,csaft", &len);
-		if (prop && len >= sizeof(*prop)) {
-			csmode &= ~(CSMODE_AFT(0xf));
-			csmode |= CSMODE_AFT(be32_to_cpup(prop));
-		}
-		fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODEx(i), csmode);
-
-		dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
-	}
-
-	/* Enable SPI interface */
-	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
-
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
+	fsl_espi_init_regs(dev, true);
 
 	pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT);
 	pm_runtime_use_autosuspend(dev);
@@ -639,8 +722,7 @@ static int fsl_espi_probe(struct device *dev, struct resource *mem,
 	if (ret < 0)
 		goto err_pm;
 
-	dev_info(dev, "at 0x%p (irq = %d)\n", mpc8xxx_spi->reg_base,
-		 mpc8xxx_spi->irq);
+	dev_info(dev, "at 0x%p (irq = %u)\n", espi->reg_base, irq);
 
 	pm_runtime_mark_last_busy(dev);
 	pm_runtime_put_autosuspend(dev);
@@ -659,20 +741,16 @@ static int fsl_espi_probe(struct device *dev, struct resource *mem,
 static int of_fsl_espi_get_chipselects(struct device *dev)
 {
 	struct device_node *np = dev->of_node;
-	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
-	const u32 *prop;
-	int len;
+	u32 num_cs;
+	int ret;
 
-	prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
-	if (!prop || len < sizeof(*prop)) {
+	ret = of_property_read_u32(np, "fsl,espi-num-chipselects", &num_cs);
+	if (ret) {
 		dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
-		return -EINVAL;
+		return 0;
 	}
 
-	pdata->max_chipselect = *prop;
-	pdata->cs_control = NULL;
-
-	return 0;
+	return num_cs;
 }
 
 static int of_fsl_espi_probe(struct platform_device *ofdev)
@@ -680,16 +758,17 @@ static int of_fsl_espi_probe(struct platform_device *ofdev)
 	struct device *dev = &ofdev->dev;
 	struct device_node *np = ofdev->dev.of_node;
 	struct resource mem;
-	unsigned int irq;
+	unsigned int irq, num_cs;
 	int ret;
 
-	ret = of_mpc8xxx_spi_probe(ofdev);
-	if (ret)
-		return ret;
+	if (of_property_read_bool(np, "mode")) {
+		dev_err(dev, "mode property is not supported on ESPI!\n");
+		return -EINVAL;
+	}
 
-	ret = of_fsl_espi_get_chipselects(dev);
-	if (ret)
-		return ret;
+	num_cs = of_fsl_espi_get_chipselects(dev);
+	if (!num_cs)
+		return -EINVAL;
 
 	ret = of_address_to_resource(np, 0, &mem);
 	if (ret)
@@ -699,7 +778,7 @@ static int of_fsl_espi_probe(struct platform_device *ofdev)
 	if (!irq)
 		return -EINVAL;
 
-	return fsl_espi_probe(dev, &mem, irq);
+	return fsl_espi_probe(dev, &mem, irq, num_cs);
 }
 
 static int of_fsl_espi_remove(struct platform_device *dev)
@@ -721,38 +800,15 @@ static int of_fsl_espi_suspend(struct device *dev)
 		return ret;
 	}
 
-	ret = pm_runtime_force_suspend(dev);
-	if (ret < 0)
-		return ret;
-
-	return 0;
+	return pm_runtime_force_suspend(dev);
 }
 
 static int of_fsl_espi_resume(struct device *dev)
 {
-	struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
 	struct spi_master *master = dev_get_drvdata(dev);
-	struct mpc8xxx_spi *mpc8xxx_spi;
-	u32 regval;
-	int i, ret;
-
-	mpc8xxx_spi = spi_master_get_devdata(master);
-
-	/* SPI controller initializations */
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM, 0);
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIE, 0xffffffff);
-
-	/* Init eSPI CS mode register */
-	for (i = 0; i < pdata->max_chipselect; i++)
-		fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODEx(i),
-				      CSMODE_INIT_VAL);
-
-	/* Enable SPI interface */
-	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+	int ret;
 
-	fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
+	fsl_espi_init_regs(dev, false);
 
 	ret = pm_runtime_force_resume(dev);
 	if (ret < 0)

drivers/spi/spi-fsl-lib.h

@@ -28,10 +28,6 @@ struct mpc8xxx_spi {
 	/* rx & tx bufs from the spi_transfer */
 	const void *tx;
 	void *rx;
-#if IS_ENABLED(CONFIG_SPI_FSL_ESPI)
-	int len;
-	u8 *local_buf;
-#endif
 
 	int subblock;
 	struct spi_pram __iomem *pram;

drivers/spi/spi.c

@@ -1042,8 +1042,14 @@ static int spi_transfer_one_message(struct spi_master *master,
 		if (msg->status != -EINPROGRESS)
 			goto out;
 
-		if (xfer->delay_usecs)
-			udelay(xfer->delay_usecs);
+		if (xfer->delay_usecs) {
+			u16 us = xfer->delay_usecs;
+
+			if (us <= 10)
+				udelay(us);
+			else
+				usleep_range(us, us + DIV_ROUND_UP(us, 10));
+		}
 
 		if (xfer->cs_change) {
 			if (list_is_last(&xfer->transfer_list,