Add Freescale DSPI driver for Vybrid VF610 platform

From: Chao Fu <[email protected]>

The serial peripheral interface (SPI) module implemented on Freescale Vybrid platform provides a synchronous serial bus for communication between Vybrid and the external peripheral device.
The SPI supports full-duplex, three-wire synchronous transfer, has TX/RX FIFO with depth of four entries.

This driver is the SPI master mode driver and has been tested on Vybrid VF610TWR board.

Signed-off-by Alison Wang <[email protected]>

Signed-off-by Chao Fu <[email protected]>

---
Changes in v2: None

 drivers/spi/Kconfig        |   6 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-fsl-dspi.c | 673 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 680 insertions(+)
 create mode 100644 drivers/spi/spi-fsl-dspi.c

drivers/spi/Kconfig +6 -0

index 89cbbab..068715d 100644
@@ -248,6 +248,12 @@ config SPI_FSL_SPI
 	  This also enables using the Aeroflex Gaisler GRLIB SPI controller in
 	  master mode.
 
+config SPI_FSL_DSPI
+         tristate "Freescale DSPI controller"
+         help
+         This enables support for the Freescale DSPI controller in master
+         mode.
+
 config SPI_FSL_ESPI
 	bool "Freescale eSPI controller"
 	depends on FSL_SOC

drivers/spi/Makefile +1 -0

index 33f9c09..78416fd 100644
@@ -31,6 +31,7 @@ obj-$(CONFIG_SPI_EP93XX)		+= spi-ep93xx.o
 obj-$(CONFIG_SPI_FALCON)		+= spi-falcon.o
 obj-$(CONFIG_SPI_FSL_CPM)		+= spi-fsl-cpm.o
 obj-$(CONFIG_SPI_FSL_LIB)		+= spi-fsl-lib.o
+obj-$(CONFIG_SPI_FSL_DSPI)		+= spi-fsl-dspi.o
 obj-$(CONFIG_SPI_FSL_ESPI)		+= spi-fsl-espi.o
 obj-$(CONFIG_SPI_FSL_SPI)		+= spi-fsl-spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi-gpio.o

drivers/spi/spi-fsl-dspi.c new file +77 -0

new file mode 100644
index 0000000..a187b6f
@@ -0,0 +1,673 @@
+/*
+ * drivers/spi/spi-fsl-dspi.c
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * Freescale DSPI driver
+ * This file contains a driver for the Freescale DSPI
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#define DRIVER_NAME "fsl-dspi"
+
+#define TRAN_STATE_RX_VOID		0x01
+#define TRAN_STATE_TX_VOID		0x02
+#define TRAN_STATE_WORD_ODD_NUM		0x04
+
+#define DSPI_FIFO_SIZE			4
+
+#define SPI_MCR			0x00
+#define SPI_TCR			0x08
+
+#define SPI_CTAR(x)		(0x0c + (x * 4))
+#define SPI_CTAR_FMSZ(x)	(((x) & 0x0000000f) << 27)
+#define SPI_CTAR_CPOL(x)	((x) << 26)
+#define SPI_CTAR_CPHA(x)	((x) << 25)
+#define SPI_CTAR_PCSSCR(x)	(((x) & 0x00000003) << 22)
+#define SPI_CTAR_PASC(x)	(((x) & 0x00000003) << 20)
+#define SPI_CTAR_PDT(x)		(((x) & 0x00000003) << 18)
+#define SPI_CTAR_PBR(x)		(((x) & 0x00000003) << 16)
+#define SPI_CTAR_CSSCK(x)	(((x) & 0x0000000f) << 12)
+#define SPI_CTAR_ASC(x)		(((x) & 0x0000000f) << 8)
+#define SPI_CTAR_DT(x)		(((x) & 0x0000000f) << 4)
+#define SPI_CTAR_BR(x)		((x) & 0x0000000f)
+
+#define SPI_CTAR0_SLAVE		0x0c
+
+#define SPI_SR			0x2c
+#define SPI_SR_EOQF		0x10000000
+
+#define SPI_RSER		0x30
+#define SPI_RSER_EOQFE		0x10000000
+
+#define SPI_PUSHR		0x34
+#define SPI_PUSHR_CONT		(1 << 31)
+#define SPI_PUSHR_CTAS(x)	(((x) & 0x00000007) << 28)
+#define SPI_PUSHR_EOQ		(1 << 27)
+#define SPI_PUSHR_CTCNT		(1 << 26)
+#define SPI_PUSHR_PCS(x)	(((1 << x) & 0x0000003f) << 16)
+#define SPI_PUSHR_TXDATA(x)	((x) & 0x0000ffff)
+
+#define SPI_PUSHR_SLAVE		0x34
+
+#define SPI_POPR		0x38
+#define SPI_POPR_RXDATA(x)	((x) & 0x0000ffff)
+
+#define SPI_TXFR0		0x3c
+#define SPI_TXFR1		0x40

drivers/spi/spi-fsl-dspi.c new file +41 -0

+
+#define SPI_CS_INIT		0x01
+#define SPI_CS_ASSERT		0x02
+#define SPI_CS_DROP		0x04
+
+struct DSPI_MCR {
+	unsigned halt:1;
+	unsigned reserved71:7;
+	unsigned smpl_pt:2;
+	unsigned clr_rxf:1;
+	unsigned clr_tx:1;
+	unsigned dis_rxf:1;
+	unsigned dis_tx:1;
+	unsigned mdis:1;
+	unsigned reserved15:1;
+	unsigned pcsis:8;
+	unsigned rooe:1;
+	unsigned pcsse:1;
+	unsigned mtfe:1;
+	unsigned frz:1;
+	unsigned dconf:2;
+	unsigned cont_scke:1;
+	unsigned master:1;
+};
+
+struct DSPI_CTAR {
+	unsigned br:4;
+	unsigned dt:4;
+	unsigned asc:4;
+	unsigned cssck:4;
+	unsigned pbr:2;
+	unsigned pdt:2;
+	unsigned pasc:2;
+	unsigned pcssck:2;
+	unsigned lsbfe:1;
+	unsigned cpha:1;
+	unsigned cpol:1;
+	unsigned fmsz:4;
+	unsigned dbr:1;
+};
+

drivers/spi/spi-fsl-dspi.c new file +44 -0

+	u16 void_write_data;
+};
+
+struct fsl_dspi {
+	struct platform_device *pdev;
+	struct spi_master *master;
+
+	void *base;
+	int irq;
+	struct clk *clk;
+
+	struct spi_message *cur_msg;
+	struct spi_transfer *cur_transfer;
+	struct chip_data *cur_chip;
+	size_t len;
+	void *tx;
+	void *tx_end;
+	void *rx;
+	void *rx_end;
+	char dataflags;
+	u8 cs;
+	u16 void_write_data;
+	unsigned	cs_change:1;
+
+	wait_queue_head_t waitq;
+	u32 waitflags;
+};
+
+/* SPI local functions */
+static inline int is_word_transfer(struct fsl_dspi *dspi)
+{
+	return ((readl(dspi->base + SPI_CTAR(dspi->cs)) & SPI_FRAME_BITS)
+			== SPI_FRAME_BITS_8) ? 0 : 1;
+}
+
+static void set_8bit_transfer_mode(struct fsl_dspi *dspi)
+{
+	u32 temp;
+
+	temp = readl(dspi->base + SPI_CTAR(dspi->cs));
+	temp &= ~SPI_FRAME_BITS;
+	temp |= SPI_FRAME_BITS_8;
+	writel(temp, dspi->base + SPI_CTAR(dspi->cs));
+}

drivers/spi/spi-fsl-dspi.c new file +11 -0

+
+static unsigned char hz_to_spi_baud(int pbr, int dbr, int speed_hz,
+		unsigned long clkrate)
+{
+	/* Valid baud rate pre-scaler values */
+	int pbr_tbl[4] = {2, 3, 5, 7};
+	int brs[16] = {	2,	4,	6,	8,
+		16,	32,	64,	128,
+		256,	512,	1024,	2048,
+		4096,	8192,	16384,	32768 };
+	int temp, index = 0;

drivers/spi/spi-fsl-dspi.c new file +4 -0

+
+static int dspi_transfer_write(struct fsl_dspi *dspi)
+{
+	int tx_count = 0;

drivers/spi/spi-fsl-dspi.c new file +90 -0

+	if (tx_word && (dspi->len == 1)) {
+		dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM;
+		set_8bit_transfer_mode(dspi);
+		tx_word = 0;
+	}
+	while (dspi->len && (tx_count < DSPI_FIFO_SIZE)) {
+		if (tx_word) {
+			if (dspi->len == 1)
+				break;
+
+			if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) {
+				d16 = *(u16 *)dspi->tx;
+				dspi->tx += 2;
+			} else {
+				d16 = dspi->void_write_data;
+			}
+
+			dspi_pushr = SPI_PUSHR_TXDATA(d16) |
+				SPI_PUSHR_PCS(dspi->cs) |
+				SPI_PUSHR_CTAS(dspi->cs) |
+				SPI_PUSHR_CONT;
+
+			dspi->len -= 2;
+		} else {
+			if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) {
+
+				d8 = *(u8 *)dspi->tx;
+				dspi->tx++;
+			} else {
+				d8 = (u8)dspi->void_write_data;
+			}
+
+			dspi_pushr = SPI_PUSHR_TXDATA(d8) |
+				SPI_PUSHR_PCS(dspi->cs) |
+				SPI_PUSHR_CTAS(dspi->cs) |
+				SPI_PUSHR_CONT;
+
+			dspi->len--;
+		}
+
+		if (dspi->len == 0
+				|| tx_count == DSPI_FIFO_SIZE - 1) {
+			/* last transfer in the queue */
+			dspi_pushr |= SPI_PUSHR_EOQ;
+			if ((dspi->cs_change)
+					&& (!dspi->len))
+				dspi_pushr &= ~SPI_PUSHR_CONT;
+		} else if (tx_word && (dspi->len == 1))
+			dspi_pushr |= SPI_PUSHR_EOQ;
+
+		if (first) {
+			first = 0;
+			dspi_pushr |= SPI_PUSHR_CTCNT; /* clear counter */
+		}
+
+		writel(dspi_pushr, dspi->base + SPI_PUSHR);
+		tx_count++;
+	}
+
+	return tx_count * (tx_word + 1);
+}
+static int dspi_transfer_read(struct fsl_dspi *dspi)
+{
+	int rx_count = 0;
+	int rx_word = is_word_transfer(dspi);
+	u16 d;
+	while ((dspi->rx < dspi->rx_end)
+			&& (rx_count < DSPI_FIFO_SIZE)) {
+		if (rx_word) {
+			if ((dspi->rx_end - dspi->rx) == 1)
+				break;
+
+			d = SPI_POPR_RXDATA(readl(dspi->base + SPI_POPR));
+
+			if (!(dspi->dataflags & TRAN_STATE_RX_VOID))
+				*(u16 *)dspi->rx = d;
+			dspi->rx += 2;
+
+		} else {
+			d = SPI_POPR_RXDATA(readl(dspi->base + SPI_POPR));
+			if (!(dspi->dataflags & TRAN_STATE_RX_VOID))
+				*(u8 *)dspi->rx = d;
+			dspi->rx++;
+		}
+		rx_count++;
+	}
+
+	return rx_count;
+}
+

drivers/spi/spi-fsl-dspi.c new file +26 -0

+		dspi->cur_msg = message;
+		dspi->cur_transfer = transfer;
+		dspi->cur_chip = spi_get_ctldata(spi);
+		dspi->cs = spi->chip_select;
+		if (dspi->cur_transfer->transfer_list.next
+				== &dspi->cur_msg->transfers)
+			transfer->cs_change = 1;
+		dspi->cs_change = transfer->cs_change;
+		dspi->void_write_data = dspi->cur_chip->void_write_data;
+
+		dspi_setup_chip(dspi);
+
+		dspi->dataflags = 0;
+		dspi->tx = (void *)transfer->tx_buf;
+		dspi->tx_end = dspi->tx + transfer->len;
+		dspi->rx = transfer->rx_buf;
+		dspi->rx_end = dspi->rx + transfer->len;
+		dspi->len = transfer->len;
+
+		if (!dspi->rx)
+			dspi->dataflags |= TRAN_STATE_RX_VOID;
+
+		if (!dspi->tx)
+			dspi->dataflags |= TRAN_STATE_TX_VOID;
+
+		if (transfer->speed_hz)

drivers/spi/spi-fsl-dspi.c new file +57 -0

+		dspi->waitflags = 0;
+
+		if (transfer->delay_usecs)
+			udelay(transfer->delay_usecs);
+	}
+	message->status = status;
+	spi_finalize_current_message(master);
+
+	return status;
+}
+
+static int dspi_prepare_transfer_hw(struct spi_master *master)
+{
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&dspi->pdev->dev);
+
+	return 0;
+}
+
+static int dspi_unprepare_transfer_hw(struct spi_master *master)
+{
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_put_sync(&dspi->pdev->dev);
+
+	return 0;
+}
+
+static int dspi_setup(struct spi_device *spi)
+{
+	struct chip_data *chip;
+	struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
+	struct device_node *np = spi->dev.of_node;
+	unsigned char br = 0;
+	unsigned int dbr = 0 , pbr = 0;
+
+	/* Only alloc on first setup */
+	chip = spi_get_ctldata(spi);
+	if (chip == NULL) {
+		chip = kcalloc(1, sizeof(struct chip_data), GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+	}
+
+	chip->mcr.master = 1;
+	chip->mcr.cont_scke = 0;
+	chip->mcr.dconf = 0;
+	chip->mcr.frz = 0;
+	chip->mcr.mtfe = 0;
+	chip->mcr.pcsse = 0;
+	chip->mcr.rooe = 0;
+	chip->mcr.pcsis = 0xFF;
+	chip->mcr.reserved15 = 0;
+	chip->mcr.mdis = 0;
+	chip->mcr.dis_tx = 0;
+	chip->mcr.dis_rxf = 0;

drivers/spi/spi-fsl-dspi.c new file +119 -0

+	br = hz_to_spi_baud(chip->ctar.pbr, chip->ctar.dbr,
+			spi->max_speed_hz, clk_get_rate(dspi->clk));
+	chip->ctar.br = br;
+	chip->ctar.pcssck = 0;
+	chip->ctar.pasc = 0;
+	chip->ctar.pdt = 0;
+	chip->ctar.cssck = 0;
+	chip->ctar.asc = 0;
+	chip->ctar.dt = 0;
+
+	spi_set_ctldata(spi, chip);
+
+	return 0;
+}
+
+static void dspi_cleanup(struct spi_device *spi)
+{
+	struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
+
+	dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
+			spi->master->bus_num, spi->chip_select);
+
+	kfree(chip);
+}
+
+static irqreturn_t dspi_interrupt(int irq, void *dev_id)
+{
+	struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
+	struct spi_message *msg = dspi->cur_msg;
+
+	writel(SPI_SR_EOQF, dspi->base + SPI_SR);
+
+	if (!dspi->cur_msg) {
+		u32 irq_status = readl(dspi->base + SPI_SR);
+		printk(KERN_ERR "Bad message or transfer state handler. "
+				"IRQ status = %x\n", irq_status);
+		return IRQ_HANDLED;
+	}
+
+	dspi_transfer_read(dspi);
+
+	if (!dspi->len) {
+		/*
+		 * Finished now - fall through and schedule next
+		 * transfer tasklet
+		 */
+		if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM)
+			set_16bit_transfer_mode(dspi);
+		dspi->waitflags = 1;
+		wake_up_interruptible(&dspi->waitq);
+
+	} else {
+		/* not finished yet - keep going */
+		msg->actual_length += dspi_transfer_write(dspi);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static struct of_device_id fsl_dspi_dt_ids[] = {
+	{ .compatible = "fsl,vf610-dspi", .data = NULL, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
+
+#ifdef CONFIG_PM_SLEEP
+static int dspi_suspend(struct device *dev)
+{
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	spi_master_suspend(master);
+	clk_disable_unprepare(dspi->clk);
+
+	return 0;
+}
+
+static int dspi_resume(struct device *dev)
+{
+
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	clk_prepare_enable(dspi->clk);
+	spi_master_resume(master);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops dspi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(dspi_suspend, dspi_resume)
+};
+
+static int dspi_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct spi_master *master;
+	struct fsl_dspi *dspi;
+	struct resource *res;
+	int ret = 0, cs_num, bus_num;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi));
+	if (!master)
+		return -ENOMEM;
+
+	dspi = spi_master_get_devdata(master);
+	dspi->master = master;
+
+	master->cleanup = dspi_cleanup;
+	master->setup = dspi_setup;
+	master->transfer = NULL;
+	master->transfer_one_message = dspi_transfer_one_message;
+	master->prepare_transfer_hardware = dspi_prepare_transfer_hw;
+	master->unprepare_transfer_hardware = dspi_unprepare_transfer_hw;
+	master->mode_bits = SPI_CPOL | SPI_CPHA;
+	master->bits_per_word_mask = SPI_BPW_MASK(4) | SPI_BPW_MASK(8) |
+					SPI_BPW_MASK(16);
+	master->dev.of_node = pdev->dev.of_node;

drivers/spi/spi-fsl-dspi.c new file +33 -0

+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "can't get platform resource\n");
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	dspi->base = devm_ioremap_resource(&pdev->dev, res);
+	if (!dspi->base) {
+		ret = EINVAL;
+		goto fail;
+	}
+
+	dspi->irq = platform_get_irq(pdev, 0);
+	if (dspi->irq < 0) {
+		dev_err(&pdev->dev, "can't get platform irq\n");
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, 0,
+			pdev->name, dspi);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
+		goto fail;
+	}
+
+	dspi->clk = devm_clk_get(&pdev->dev, "dspi");
+	if (IS_ERR(dspi->clk)) {
+		dev_err(&pdev->dev, "unable to get clock\n");
+		goto fail;
+	}

drivers/spi/spi-fsl-dspi.c new file +7 -0

+		goto fail;
+	}
+
+	printk(KERN_INFO "Freescale DSPI master initialized\n");
+	return ret;
+
+fail:

drivers/spi/spi-fsl-dspi.c new file +17 -0

+
+	return 0;
+}
+
+static struct platform_driver fsl_dspi_driver = {
+	.driver.name    = DRIVER_NAME,
+	.driver.of_match_table = fsl_dspi_dt_ids,
+	.driver.owner   = THIS_MODULE,
+	.driver.pm = &dspi_pm,
+	.probe          = dspi_probe,
+	.remove		= dspi_remove,
+};
+module_platform_driver(fsl_dspi_driver);
+
+MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);

Signature · 8 lines

1.8.0



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On Wed, Jul 24, 2013 at 01:32:23PM +0800, Chao Fu wrote:

drivers/spi/spi-fsl-dspi.c line 240

Quoted 4 lines

drivers/spi/spi-fsl-dspi.c new file +4 -0

+	tx_word = is_word_transfer(dspi);
+	/* If we are in word mode, but only have a single byte to transfer
+	 * then switch to byte mode temporarily.  Will switch back at the
+	 * end of the transfer. */

Not sure if I understand this, but if you are in word mode then I would consider it a bug when there's only one byte to transfer.

drivers/spi/spi-fsl-dspi.c line 395

Quoted 8 lines

drivers/spi/spi-fsl-dspi.c new file +8 -0

+static int dspi_prepare_transfer_hw(struct spi_master *master)
+{
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&dspi->pdev->dev);
+
+	return 0;
+}

On Wed, Jul 24, 2013 at 01:32:23PM +0800, Chao Fu wrote:

drivers/spi/spi-fsl-dspi.c line 240

Quoted 4 lines

drivers/spi/spi-fsl-dspi.c new file +4 -0

+	tx_word = is_word_transfer(dspi);
+	/* If we are in word mode, but only have a single byte to transfer
+	 * then switch to byte mode temporarily.  Will switch back at the
+	 * end of the transfer. */

Not sure if I understand this, but if you are in word mode then I would consider it a bug when there's only one byte to transfer.

drivers/spi/spi-fsl-dspi.c line 395

Quoted 7 lines

drivers/spi/spi-fsl-dspi.c new file +7 -0

+static int dspi_prepare_transfer_hw(struct spi_master *master) {
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&dspi->pdev->dev);
+
+	return 0;
+}

From: Chao Fu <[email protected]>

The serial peripheral interface (SPI) module implemented on Freescale Vybrid platform provides a synchronous serial bus for communication between Vybrid and the external peripheral device.
The SPI supports full-duplex, three-wire synchronous transfer, has TX/RX FIFO with depth of four entries.

This driver is the SPI master mode driver and has been tested on Vybrid VF610TWR board.

Signed-off-by Alison Wang <[email protected]>

Signed-off-by Chao Fu <[email protected]>

---
Changes in v2: None

 drivers/spi/Kconfig        |   6 +
 drivers/spi/Makefile       |   1 +
 drivers/spi/spi-fsl-dspi.c | 673 
+++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 680 insertions(+)
 create mode 100644 drivers/spi/spi-fsl-dspi.c

drivers/spi/Kconfig index renamed from drivers/spi/Kconfig +0 -0

89cbbab..068715d 100644

drivers/spi/Kconfig +6 -0

@@ -248,6 +248,12 @@ config SPI_FSL_SPI
 	  This also enables using the Aeroflex Gaisler GRLIB SPI controller in
 	  master mode.
 
+config SPI_FSL_DSPI
+         tristate "Freescale DSPI controller"
+         help
+         This enables support for the Freescale DSPI controller in master
+         mode.
+
 config SPI_FSL_ESPI
 	bool "Freescale eSPI controller"
 	depends on FSL_SOC

drivers/spi/Makefile index renamed from drivers/spi/Makefile +0 -0

33f9c09..78416fd 100644

drivers/spi/Makefile +1 -0

@@ -31,6 +31,7 @@ obj-$(CONFIG_SPI_EP93XX)		+= spi-ep93xx.o
 obj-$(CONFIG_SPI_FALCON)		+= spi-falcon.o
 obj-$(CONFIG_SPI_FSL_CPM)		+= spi-fsl-cpm.o
 obj-$(CONFIG_SPI_FSL_LIB)		+= spi-fsl-lib.o
+obj-$(CONFIG_SPI_FSL_DSPI)		+= spi-fsl-dspi.o
 obj-$(CONFIG_SPI_FSL_ESPI)		+= spi-fsl-espi.o
 obj-$(CONFIG_SPI_FSL_SPI)		+= spi-fsl-spi.o
 obj-$(CONFIG_SPI_GPIO)			+= spi-gpio.o

drivers/spi/spi-fsl-dspi.c new file +79 -0

new file mode 100644 index 0000000..a187b6f
@@ -0,0 +1,673 @@
+/*
+ * drivers/spi/spi-fsl-dspi.c
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * Freescale DSPI driver
+ * This file contains a driver for the Freescale DSPI
+ *
+ * This program is free software; you can redistribute it and/or 
+modify
+ * it under the terms of the GNU General Public License as published 
+by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#define DRIVER_NAME "fsl-dspi"
+
+#define TRAN_STATE_RX_VOID		0x01
+#define TRAN_STATE_TX_VOID		0x02
+#define TRAN_STATE_WORD_ODD_NUM		0x04
+
+#define DSPI_FIFO_SIZE			4
+
+#define SPI_MCR			0x00
+#define SPI_TCR			0x08
+
+#define SPI_CTAR(x)		(0x0c + (x * 4))
+#define SPI_CTAR_FMSZ(x)	(((x) & 0x0000000f) << 27)
+#define SPI_CTAR_CPOL(x)	((x) << 26)
+#define SPI_CTAR_CPHA(x)	((x) << 25)
+#define SPI_CTAR_PCSSCR(x)	(((x) & 0x00000003) << 22)
+#define SPI_CTAR_PASC(x)	(((x) & 0x00000003) << 20)
+#define SPI_CTAR_PDT(x)		(((x) & 0x00000003) << 18)
+#define SPI_CTAR_PBR(x)		(((x) & 0x00000003) << 16)
+#define SPI_CTAR_CSSCK(x)	(((x) & 0x0000000f) << 12)
+#define SPI_CTAR_ASC(x)		(((x) & 0x0000000f) << 8)
+#define SPI_CTAR_DT(x)		(((x) & 0x0000000f) << 4)
+#define SPI_CTAR_BR(x)		((x) & 0x0000000f)
+
+#define SPI_CTAR0_SLAVE		0x0c
+
+#define SPI_SR			0x2c
+#define SPI_SR_EOQF		0x10000000
+
+#define SPI_RSER		0x30
+#define SPI_RSER_EOQFE		0x10000000
+
+#define SPI_PUSHR		0x34
+#define SPI_PUSHR_CONT		(1 << 31)
+#define SPI_PUSHR_CTAS(x)	(((x) & 0x00000007) << 28)
+#define SPI_PUSHR_EOQ		(1 << 27)
+#define SPI_PUSHR_CTCNT		(1 << 26)
+#define SPI_PUSHR_PCS(x)	(((1 << x) & 0x0000003f) << 16)
+#define SPI_PUSHR_TXDATA(x)	((x) & 0x0000ffff)
+
+#define SPI_PUSHR_SLAVE		0x34
+
+#define SPI_POPR		0x38
+#define SPI_POPR_RXDATA(x)	((x) & 0x0000ffff)
+
+#define SPI_TXFR0		0x3c
+#define SPI_TXFR1		0x40

drivers/spi/spi-fsl-dspi.c new file +41 -0

+
+#define SPI_CS_INIT		0x01
+#define SPI_CS_ASSERT		0x02
+#define SPI_CS_DROP		0x04
+
+struct DSPI_MCR {
+	unsigned halt:1;
+	unsigned reserved71:7;
+	unsigned smpl_pt:2;
+	unsigned clr_rxf:1;
+	unsigned clr_tx:1;
+	unsigned dis_rxf:1;
+	unsigned dis_tx:1;
+	unsigned mdis:1;
+	unsigned reserved15:1;
+	unsigned pcsis:8;
+	unsigned rooe:1;
+	unsigned pcsse:1;
+	unsigned mtfe:1;
+	unsigned frz:1;
+	unsigned dconf:2;
+	unsigned cont_scke:1;
+	unsigned master:1;
+};
+
+struct DSPI_CTAR {
+	unsigned br:4;
+	unsigned dt:4;
+	unsigned asc:4;
+	unsigned cssck:4;
+	unsigned pbr:2;
+	unsigned pdt:2;
+	unsigned pasc:2;
+	unsigned pcssck:2;
+	unsigned lsbfe:1;
+	unsigned cpha:1;
+	unsigned cpol:1;
+	unsigned fmsz:4;
+	unsigned dbr:1;
+};
+

drivers/spi/spi-fsl-dspi.c new file +39 -0

+	u16 void_write_data;
+};
+
+struct fsl_dspi {
+	struct platform_device *pdev;
+	struct spi_master *master;
+
+	void *base;
+	int irq;
+	struct clk *clk;
+
+	struct spi_message *cur_msg;
+	struct spi_transfer *cur_transfer;
+	struct chip_data *cur_chip;
+	size_t len;
+	void *tx;
+	void *tx_end;
+	void *rx;
+	void *rx_end;
+	char dataflags;
+	u8 cs;
+	u16 void_write_data;
+	unsigned	cs_change:1;
+
+	wait_queue_head_t waitq;
+	u32 waitflags;
+};
+
+/* SPI local functions */
+static inline int is_word_transfer(struct fsl_dspi *dspi) {
+	return ((readl(dspi->base + SPI_CTAR(dspi->cs)) & SPI_FRAME_BITS)
+			== SPI_FRAME_BITS_8) ? 0 : 1;
+}
+
+static void set_8bit_transfer_mode(struct fsl_dspi *dspi) {
+	u32 temp;
+
+	temp = readl(dspi->base + SPI_CTAR(dspi->cs));
+	temp &= ~SPI_FRAME_BITS;

drivers/spi/spi-fsl-dspi.c new file +11 -0

+
+static unsigned char hz_to_spi_baud(int pbr, int dbr, int speed_hz,
+		unsigned long clkrate)
+{
+	/* Valid baud rate pre-scaler values */
+	int pbr_tbl[4] = {2, 3, 5, 7};
+	int brs[16] = {	2,	4,	6,	8,
+		16,	32,	64,	128,
+		256,	512,	1024,	2048,
+		4096,	8192,	16384,	32768 };
+	int temp, index = 0;

drivers/spi/spi-fsl-dspi.c new file +89 -0

+	if (tx_word && (dspi->len == 1)) {
+		dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM;
+		set_8bit_transfer_mode(dspi);
+		tx_word = 0;
+	}
+	while (dspi->len && (tx_count < DSPI_FIFO_SIZE)) {
+		if (tx_word) {
+			if (dspi->len == 1)
+				break;
+
+			if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) {
+				d16 = *(u16 *)dspi->tx;
+				dspi->tx += 2;
+			} else {
+				d16 = dspi->void_write_data;
+			}
+
+			dspi_pushr = SPI_PUSHR_TXDATA(d16) |
+				SPI_PUSHR_PCS(dspi->cs) |
+				SPI_PUSHR_CTAS(dspi->cs) |
+				SPI_PUSHR_CONT;
+
+			dspi->len -= 2;
+		} else {
+			if (!(dspi->dataflags & TRAN_STATE_TX_VOID)) {
+
+				d8 = *(u8 *)dspi->tx;
+				dspi->tx++;
+			} else {
+				d8 = (u8)dspi->void_write_data;
+			}
+
+			dspi_pushr = SPI_PUSHR_TXDATA(d8) |
+				SPI_PUSHR_PCS(dspi->cs) |
+				SPI_PUSHR_CTAS(dspi->cs) |
+				SPI_PUSHR_CONT;
+
+			dspi->len--;
+		}
+
+		if (dspi->len == 0
+				|| tx_count == DSPI_FIFO_SIZE - 1) {
+			/* last transfer in the queue */
+			dspi_pushr |= SPI_PUSHR_EOQ;
+			if ((dspi->cs_change)
+					&& (!dspi->len))
+				dspi_pushr &= ~SPI_PUSHR_CONT;
+		} else if (tx_word && (dspi->len == 1))
+			dspi_pushr |= SPI_PUSHR_EOQ;
+
+		if (first) {
+			first = 0;
+			dspi_pushr |= SPI_PUSHR_CTCNT; /* clear counter */
+		}
+
+		writel(dspi_pushr, dspi->base + SPI_PUSHR);
+		tx_count++;
+	}
+
+	return tx_count * (tx_word + 1);
+}
+static int dspi_transfer_read(struct fsl_dspi *dspi) {
+	int rx_count = 0;
+	int rx_word = is_word_transfer(dspi);
+	u16 d;
+	while ((dspi->rx < dspi->rx_end)
+			&& (rx_count < DSPI_FIFO_SIZE)) {
+		if (rx_word) {
+			if ((dspi->rx_end - dspi->rx) == 1)
+				break;
+
+			d = SPI_POPR_RXDATA(readl(dspi->base + SPI_POPR));
+
+			if (!(dspi->dataflags & TRAN_STATE_RX_VOID))
+				*(u16 *)dspi->rx = d;
+			dspi->rx += 2;
+
+		} else {
+			d = SPI_POPR_RXDATA(readl(dspi->base + SPI_POPR));
+			if (!(dspi->dataflags & TRAN_STATE_RX_VOID))
+				*(u8 *)dspi->rx = d;
+			dspi->rx++;
+		}
+		rx_count++;
+	}
+
+	return rx_count;
+}
+

drivers/spi/spi-fsl-dspi.c new file +26 -0

+		dspi->cur_msg = message;
+		dspi->cur_transfer = transfer;
+		dspi->cur_chip = spi_get_ctldata(spi);
+		dspi->cs = spi->chip_select;
+		if (dspi->cur_transfer->transfer_list.next
+				== &dspi->cur_msg->transfers)
+			transfer->cs_change = 1;
+		dspi->cs_change = transfer->cs_change;
+		dspi->void_write_data = dspi->cur_chip->void_write_data;
+
+		dspi_setup_chip(dspi);
+
+		dspi->dataflags = 0;
+		dspi->tx = (void *)transfer->tx_buf;
+		dspi->tx_end = dspi->tx + transfer->len;
+		dspi->rx = transfer->rx_buf;
+		dspi->rx_end = dspi->rx + transfer->len;
+		dspi->len = transfer->len;
+
+		if (!dspi->rx)
+			dspi->dataflags |= TRAN_STATE_RX_VOID;
+
+		if (!dspi->tx)
+			dspi->dataflags |= TRAN_STATE_TX_VOID;
+
+		if (transfer->speed_hz)

drivers/spi/spi-fsl-dspi.c new file +54 -0

+		dspi->waitflags = 0;
+
+		if (transfer->delay_usecs)
+			udelay(transfer->delay_usecs);
+	}
+	message->status = status;
+	spi_finalize_current_message(master);
+
+	return status;
+}
+
+static int dspi_prepare_transfer_hw(struct spi_master *master) {
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_get_sync(&dspi->pdev->dev);
+
+	return 0;
+}
+
+static int dspi_unprepare_transfer_hw(struct spi_master *master) {
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	pm_runtime_put_sync(&dspi->pdev->dev);
+
+	return 0;
+}
+
+static int dspi_setup(struct spi_device *spi) {
+	struct chip_data *chip;
+	struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
+	struct device_node *np = spi->dev.of_node;
+	unsigned char br = 0;
+	unsigned int dbr = 0 , pbr = 0;
+
+	/* Only alloc on first setup */
+	chip = spi_get_ctldata(spi);
+	if (chip == NULL) {
+		chip = kcalloc(1, sizeof(struct chip_data), GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+	}
+
+	chip->mcr.master = 1;
+	chip->mcr.cont_scke = 0;
+	chip->mcr.dconf = 0;
+	chip->mcr.frz = 0;
+	chip->mcr.mtfe = 0;
+	chip->mcr.pcsse = 0;
+	chip->mcr.rooe = 0;
+	chip->mcr.pcsis = 0xFF;
+	chip->mcr.reserved15 = 0;
+	chip->mcr.mdis = 0;
+	chip->mcr.dis_tx = 0;
+	chip->mcr.dis_rxf = 0;

drivers/spi/spi-fsl-dspi.c new file +113 -0

+	br = hz_to_spi_baud(chip->ctar.pbr, chip->ctar.dbr,
+			spi->max_speed_hz, clk_get_rate(dspi->clk));
+	chip->ctar.br = br;
+	chip->ctar.pcssck = 0;
+	chip->ctar.pasc = 0;
+	chip->ctar.pdt = 0;
+	chip->ctar.cssck = 0;
+	chip->ctar.asc = 0;
+	chip->ctar.dt = 0;
+
+	spi_set_ctldata(spi, chip);
+
+	return 0;
+}
+
+static void dspi_cleanup(struct spi_device *spi) {
+	struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
+
+	dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
+			spi->master->bus_num, spi->chip_select);
+
+	kfree(chip);
+}
+
+static irqreturn_t dspi_interrupt(int irq, void *dev_id) {
+	struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
+	struct spi_message *msg = dspi->cur_msg;
+
+	writel(SPI_SR_EOQF, dspi->base + SPI_SR);
+
+	if (!dspi->cur_msg) {
+		u32 irq_status = readl(dspi->base + SPI_SR);
+		printk(KERN_ERR "Bad message or transfer state handler. "
+				"IRQ status = %x\n", irq_status);
+		return IRQ_HANDLED;
+	}
+
+	dspi_transfer_read(dspi);
+
+	if (!dspi->len) {
+		/*
+		 * Finished now - fall through and schedule next
+		 * transfer tasklet
+		 */
+		if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM)
+			set_16bit_transfer_mode(dspi);
+		dspi->waitflags = 1;
+		wake_up_interruptible(&dspi->waitq);
+
+	} else {
+		/* not finished yet - keep going */
+		msg->actual_length += dspi_transfer_write(dspi);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static struct of_device_id fsl_dspi_dt_ids[] = {
+	{ .compatible = "fsl,vf610-dspi", .data = NULL, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
+
+#ifdef CONFIG_PM_SLEEP
+static int dspi_suspend(struct device *dev) {
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	spi_master_suspend(master);
+	clk_disable_unprepare(dspi->clk);
+
+	return 0;
+}
+
+static int dspi_resume(struct device *dev) {
+
+	struct spi_master *master = dev_get_drvdata(dev);
+	struct fsl_dspi *dspi = spi_master_get_devdata(master);
+
+	clk_prepare_enable(dspi->clk);
+	spi_master_resume(master);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops dspi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(dspi_suspend, dspi_resume) };
+
+static int dspi_probe(struct platform_device *pdev) {
+	struct device_node *np = pdev->dev.of_node;
+	struct spi_master *master;
+	struct fsl_dspi *dspi;
+	struct resource *res;
+	int ret = 0, cs_num, bus_num;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi));
+	if (!master)
+		return -ENOMEM;
+
+	dspi = spi_master_get_devdata(master);
+	dspi->master = master;
+
+	master->cleanup = dspi_cleanup;
+	master->setup = dspi_setup;
+	master->transfer = NULL;
+	master->transfer_one_message = dspi_transfer_one_message;
+	master->prepare_transfer_hardware = dspi_prepare_transfer_hw;
+	master->unprepare_transfer_hardware = dspi_unprepare_transfer_hw;
+	master->mode_bits = SPI_CPOL | SPI_CPHA;
+	master->bits_per_word_mask = SPI_BPW_MASK(4) | SPI_BPW_MASK(8) |
+					SPI_BPW_MASK(16);
+	master->dev.of_node = pdev->dev.of_node;

drivers/spi/spi-fsl-dspi.c new file +33 -0

+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "can't get platform resource\n");
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	dspi->base = devm_ioremap_resource(&pdev->dev, res);
+	if (!dspi->base) {
+		ret = EINVAL;
+		goto fail;
+	}
+
+	dspi->irq = platform_get_irq(pdev, 0);
+	if (dspi->irq < 0) {
+		dev_err(&pdev->dev, "can't get platform irq\n");
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, 0,
+			pdev->name, dspi);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
+		goto fail;
+	}
+
+	dspi->clk = devm_clk_get(&pdev->dev, "dspi");
+	if (IS_ERR(dspi->clk)) {
+		dev_err(&pdev->dev, "unable to get clock\n");
+		goto fail;
+	}

drivers/spi/spi-fsl-dspi.c new file +6 -0

+		goto fail;
+	}
+
+	printk(KERN_INFO "Freescale DSPI master initialized\n");
+	return ret;
+

drivers/spi/spi-fsl-dspi.c new file +16 -1

+
+	return 0;
+}
+
+static struct platform_driver fsl_dspi_driver = {
+	.driver.name    = DRIVER_NAME,
+	.driver.of_match_table = fsl_dspi_dt_ids,
+	.driver.owner   = THIS_MODULE,
+	.driver.pm = &dspi_pm,
+	.probe          = dspi_probe,
+	.remove		= dspi_remove,
+};
+module_platform_driver(fsl_dspi_driver);
+
+MODULE_DESCRIPTION("Freescale DSPI Controller Driver"); 
+MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:" DRIVER_NAME);
--

1.8.0

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