spi: Add Freescale/Motorola Coldfire QSPI driver

Add support for the QSPI controller found some on Freescale/Motorola
Coldfire MCUs.

Full duplex, active high cs, spi modes 0-3 and word sizes 8-16 bits are
supported.  The hardware drives the MISO, MOSI and SCLK lines, but the chip
selects are managed via GPIO and must be configured by the board code.

The QSPI controller has an 80 byte buffer which allows us to transfer up to 16
words at a time.  For transfers longer than 16 words, we split the buffer in
half so we can update in one half while the controller is operating on the
other half.  Interrupt latencies then ultimately limits our sustained thru-put
to something less than half the maximum speed supported by the part.
Signed-off-by: Steven King <sfking@fdwdc.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/spi/Kconfig

@@ -100,6 +100,16 @@ config SPI_BUTTERFLY
 	  inexpensive battery powered microcontroller evaluation board.
 	  This same cable can be used to flash new firmware.
 
+config SPI_COLDFIRE_QSPI
+	tristate "Freescale Coldfire QSPI controller"
+	depends on (M520x || M523x || M5249 || M527x || M528x || M532x)
+	help
+	  This enables support for the Coldfire QSPI controller in master
+	  mode.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called coldfire_qspi.
+
 config SPI_DAVINCI
 	tristate "SPI controller driver for DaVinci/DA8xx SoC's"
 	depends on SPI_MASTER && ARCH_DAVINCI

drivers/spi/Makefile

@@ -16,6 +16,7 @@ obj-$(CONFIG_SPI_BFIN)			+= spi_bfin5xx.o
 obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o
 obj-$(CONFIG_SPI_AU1550)		+= au1550_spi.o
 obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o
+obj-$(CONFIG_SPI_COLDFIRE_QSPI)		+= coldfire_qspi.o
 obj-$(CONFIG_SPI_DAVINCI)		+= davinci_spi.o
 obj-$(CONFIG_SPI_DESIGNWARE)		+= dw_spi.o
 obj-$(CONFIG_SPI_DW_PCI)		+= dw_spi_pci.o

drivers/spi/coldfire_qspi.c

+/*
+ * Freescale/Motorola Coldfire Queued SPI driver
+ *
+ * Copyright 2010 Steven King <sfking@fdwdc.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
+ *
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+
+#include <asm/coldfire.h>
+#include <asm/mcfqspi.h>
+
+#define	DRIVER_NAME "mcfqspi"
+
+#define	MCFQSPI_BUSCLK			(MCF_BUSCLK / 2)
+
+#define	MCFQSPI_QMR			0x00
+#define		MCFQSPI_QMR_MSTR	0x8000
+#define		MCFQSPI_QMR_CPOL	0x0200
+#define		MCFQSPI_QMR_CPHA	0x0100
+#define	MCFQSPI_QDLYR			0x04
+#define		MCFQSPI_QDLYR_SPE	0x8000
+#define	MCFQSPI_QWR			0x08
+#define		MCFQSPI_QWR_HALT	0x8000
+#define		MCFQSPI_QWR_WREN	0x4000
+#define		MCFQSPI_QWR_CSIV	0x1000
+#define	MCFQSPI_QIR			0x0C
+#define		MCFQSPI_QIR_WCEFB	0x8000
+#define		MCFQSPI_QIR_ABRTB	0x4000
+#define		MCFQSPI_QIR_ABRTL	0x1000
+#define		MCFQSPI_QIR_WCEFE	0x0800
+#define		MCFQSPI_QIR_ABRTE	0x0400
+#define		MCFQSPI_QIR_SPIFE	0x0100
+#define		MCFQSPI_QIR_WCEF	0x0008
+#define		MCFQSPI_QIR_ABRT	0x0004
+#define		MCFQSPI_QIR_SPIF	0x0001
+#define	MCFQSPI_QAR			0x010
+#define		MCFQSPI_QAR_TXBUF	0x00
+#define		MCFQSPI_QAR_RXBUF	0x10
+#define		MCFQSPI_QAR_CMDBUF	0x20
+#define	MCFQSPI_QDR			0x014
+#define	MCFQSPI_QCR			0x014
+#define		MCFQSPI_QCR_CONT	0x8000
+#define		MCFQSPI_QCR_BITSE	0x4000
+#define		MCFQSPI_QCR_DT		0x2000
+
+struct mcfqspi {
+	void __iomem *iobase;
+	int irq;
+	struct clk *clk;
+	struct mcfqspi_cs_control *cs_control;
+
+	wait_queue_head_t waitq;
+
+	struct work_struct work;
+	struct workqueue_struct *workq;
+	spinlock_t lock;
+	struct list_head msgq;
+};
+
+static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QMR);
+}
+
+static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
+}
+
+static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
+{
+	return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
+}
+
+static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QWR);
+}
+
+static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QIR);
+}
+
+static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QAR);
+}
+
+static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
+{
+	writew(val, mcfqspi->iobase + MCFQSPI_QDR);
+}
+
+static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
+{
+	return readw(mcfqspi->iobase + MCFQSPI_QDR);
+}
+
+static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
+			    bool cs_high)
+{
+	mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
+}
+
+static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
+				bool cs_high)
+{
+	mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
+}
+
+static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
+{
+	return (mcfqspi->cs_control && mcfqspi->cs_control->setup) ?
+		mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
+}
+
+static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
+{
+	if (mcfqspi->cs_control && mcfqspi->cs_control->teardown)
+		mcfqspi->cs_control->teardown(mcfqspi->cs_control);
+}
+
+static u8 mcfqspi_qmr_baud(u32 speed_hz)
+{
+	return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
+}
+
+static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
+{
+	return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
+}
+
+static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
+{
+	struct mcfqspi *mcfqspi = dev_id;
+
+	/* clear interrupt */
+	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
+	wake_up(&mcfqspi->waitq);
+
+	return IRQ_HANDLED;
+}
+
+static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
+				  const u8 *txbuf, u8 *rxbuf)
+{
+	unsigned i, n, offset = 0;
+
+	n = min(count, 16u);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
+	for (i = 0; i < n; ++i)
+		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
+	if (txbuf)
+		for (i = 0; i < n; ++i)
+			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+	else
+		for (i = 0; i < count; ++i)
+			mcfqspi_wr_qdr(mcfqspi, 0);
+
+	count -= n;
+	if (count) {
+		u16 qwr = 0xf08;
+		mcfqspi_wr_qwr(mcfqspi, 0x700);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+
+		do {
+			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+			mcfqspi_wr_qwr(mcfqspi, qwr);
+			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+			if (rxbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_RXBUF + offset);
+				for (i = 0; i < 8; ++i)
+					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			}
+			n = min(count, 8u);
+			if (txbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_TXBUF + offset);
+				for (i = 0; i < n; ++i)
+					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+			}
+			qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
+			offset ^= 8;
+			count -= n;
+		} while (count);
+		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+		mcfqspi_wr_qwr(mcfqspi, qwr);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+		if (rxbuf) {
+			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+			for (i = 0; i < 8; ++i)
+				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			offset ^= 8;
+		}
+	} else {
+		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+	}
+	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+	if (rxbuf) {
+		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+		for (i = 0; i < n; ++i)
+			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+	}
+}
+
+static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
+				   const u16 *txbuf, u16 *rxbuf)
+{
+	unsigned i, n, offset = 0;
+
+	n = min(count, 16u);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
+	for (i = 0; i < n; ++i)
+		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
+
+	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
+	if (txbuf)
+		for (i = 0; i < n; ++i)
+			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+	else
+		for (i = 0; i < count; ++i)
+			mcfqspi_wr_qdr(mcfqspi, 0);
+
+	count -= n;
+	if (count) {
+		u16 qwr = 0xf08;
+		mcfqspi_wr_qwr(mcfqspi, 0x700);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+
+		do {
+			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+			mcfqspi_wr_qwr(mcfqspi, qwr);
+			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+			if (rxbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_RXBUF + offset);
+				for (i = 0; i < 8; ++i)
+					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			}
+			n = min(count, 8u);
+			if (txbuf) {
+				mcfqspi_wr_qar(mcfqspi,
+					       MCFQSPI_QAR_TXBUF + offset);
+				for (i = 0; i < n; ++i)
+					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
+			}
+			qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
+			offset ^= 8;
+			count -= n;
+		} while (count);
+		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+		mcfqspi_wr_qwr(mcfqspi, qwr);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+		if (rxbuf) {
+			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+			for (i = 0; i < 8; ++i)
+				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+			offset ^= 8;
+		}
+	} else {
+		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
+		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
+	}
+	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
+	if (rxbuf) {
+		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
+		for (i = 0; i < n; ++i)
+			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
+	}
+}
+
+static void mcfqspi_work(struct work_struct *work)
+{
+	struct mcfqspi *mcfqspi = container_of(work, struct mcfqspi, work);
+	unsigned long flags;
+
+	spin_lock_irqsave(&mcfqspi->lock, flags);
+	while (!list_empty(&mcfqspi->msgq)) {
+		struct spi_message *msg;
+		struct spi_device *spi;
+		struct spi_transfer *xfer;
+		int status = 0;
+
+		msg = container_of(mcfqspi->msgq.next, struct spi_message,
+				   queue);
+
+		list_del_init(&mcfqspi->msgq);
+		spin_unlock_irqrestore(&mcfqspi->lock, flags);
+
+		spi = msg->spi;
+
+		list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+			bool cs_high = spi->mode & SPI_CS_HIGH;
+			u16 qmr = MCFQSPI_QMR_MSTR;
+
+			if (xfer->bits_per_word)
+				qmr |= xfer->bits_per_word << 10;
+			else
+				qmr |= spi->bits_per_word << 10;
+			if (spi->mode & SPI_CPHA)
+				qmr |= MCFQSPI_QMR_CPHA;
+			if (spi->mode & SPI_CPOL)
+				qmr |= MCFQSPI_QMR_CPOL;
+			if (xfer->speed_hz)
+				qmr |= mcfqspi_qmr_baud(xfer->speed_hz);
+			else
+				qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
+			mcfqspi_wr_qmr(mcfqspi, qmr);
+
+			mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
+
+			mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
+			if ((xfer->bits_per_word ? xfer->bits_per_word :
+						spi->bits_per_word) == 8)
+				mcfqspi_transfer_msg8(mcfqspi, xfer->len,
+						      xfer->tx_buf,
+						      xfer->rx_buf);
+			else
+				mcfqspi_transfer_msg16(mcfqspi, xfer->len / 2,
+						       xfer->tx_buf,
+						       xfer->rx_buf);
+			mcfqspi_wr_qir(mcfqspi, 0);
+
+			if (xfer->delay_usecs)
+				udelay(xfer->delay_usecs);
+			if (xfer->cs_change) {
+				if (!list_is_last(&xfer->transfer_list,
+						  &msg->transfers))
+					mcfqspi_cs_deselect(mcfqspi,
+							    spi->chip_select,
+							    cs_high);
+			} else {
+				if (list_is_last(&xfer->transfer_list,
+						 &msg->transfers))
+					mcfqspi_cs_deselect(mcfqspi,
+							    spi->chip_select,
+							    cs_high);
+			}
+			msg->actual_length += xfer->len;
+		}
+		msg->status = status;
+		msg->complete(msg->context);
+
+		spin_lock_irqsave(&mcfqspi->lock, flags);
+	}
+	spin_unlock_irqrestore(&mcfqspi->lock, flags);
+}
+
+static int mcfqspi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	struct mcfqspi *mcfqspi;
+	struct spi_transfer *xfer;
+	unsigned long flags;
+
+	mcfqspi = spi_master_get_devdata(spi->master);
+
+	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+		if (xfer->bits_per_word && ((xfer->bits_per_word < 8)
+					|| (xfer->bits_per_word > 16))) {
+			dev_dbg(&spi->dev,
+				"%d bits per word is not supported\n",
+				xfer->bits_per_word);
+			goto fail;
+		}
+		if (xfer->speed_hz) {
+			u32 real_speed = MCFQSPI_BUSCLK /
+				mcfqspi_qmr_baud(xfer->speed_hz);
+			if (real_speed != xfer->speed_hz)
+				dev_dbg(&spi->dev,
+					"using speed %d instead of %d\n",
+					real_speed, xfer->speed_hz);
+		}
+	}
+	msg->status = -EINPROGRESS;
+	msg->actual_length = 0;
+
+	spin_lock_irqsave(&mcfqspi->lock, flags);
+	list_add_tail(&msg->queue, &mcfqspi->msgq);
+	queue_work(mcfqspi->workq, &mcfqspi->work);
+	spin_unlock_irqrestore(&mcfqspi->lock, flags);
+
+	return 0;
+fail:
+	msg->status = -EINVAL;
+	return -EINVAL;
+}
+
+static int mcfqspi_setup(struct spi_device *spi)
+{
+	if ((spi->bits_per_word < 8) || (spi->bits_per_word > 16)) {
+		dev_dbg(&spi->dev, "%d bits per word is not supported\n",
+			spi->bits_per_word);
+		return -EINVAL;
+	}
+	if (spi->chip_select >= spi->master->num_chipselect) {
+		dev_dbg(&spi->dev, "%d chip select is out of range\n",
+			spi->chip_select);
+		return -EINVAL;
+	}
+
+	mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
+			    spi->chip_select, spi->mode & SPI_CS_HIGH);
+
+	dev_dbg(&spi->dev,
+			"bits per word %d, chip select %d, speed %d KHz\n",
+			spi->bits_per_word, spi->chip_select,
+			(MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
+			/ 1000);
+
+	return 0;
+}
+
+static int __devinit mcfqspi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct mcfqspi *mcfqspi;
+	struct resource *res;
+	struct mcfqspi_platform_data *pdata;
+	int status;
+
+	master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
+	if (master == NULL) {
+		dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
+		return -ENOMEM;
+	}
+
+	mcfqspi = spi_master_get_devdata(master);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_dbg(&pdev->dev, "platform_get_resource failed\n");
+		status = -ENXIO;
+		goto fail0;
+	}
+
+	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+		dev_dbg(&pdev->dev, "request_mem_region failed\n");
+		status = -EBUSY;
+		goto fail0;
+	}
+
+	mcfqspi->iobase = ioremap(res->start, resource_size(res));
+	if (!mcfqspi->iobase) {
+		dev_dbg(&pdev->dev, "ioremap failed\n");
+		status = -ENOMEM;
+		goto fail1;
+	}
+
+	mcfqspi->irq = platform_get_irq(pdev, 0);
+	if (mcfqspi->irq < 0) {
+		dev_dbg(&pdev->dev, "platform_get_irq failed\n");
+		status = -ENXIO;
+		goto fail2;
+	}
+
+	status = request_irq(mcfqspi->irq, mcfqspi_irq_handler, IRQF_DISABLED,
+			     pdev->name, mcfqspi);
+	if (status) {
+		dev_dbg(&pdev->dev, "request_irq failed\n");
+		goto fail2;
+	}
+
+	mcfqspi->clk = clk_get(&pdev->dev, "qspi_clk");
+	if (IS_ERR(mcfqspi->clk)) {
+		dev_dbg(&pdev->dev, "clk_get failed\n");
+		status = PTR_ERR(mcfqspi->clk);
+		goto fail3;
+	}
+	clk_enable(mcfqspi->clk);
+
+	mcfqspi->workq = create_singlethread_workqueue(dev_name(master->dev.parent));
+	if (!mcfqspi->workq) {
+		dev_dbg(&pdev->dev, "create_workqueue failed\n");
+		status = -ENOMEM;
+		goto fail4;
+	}
+	INIT_WORK(&mcfqspi->work, mcfqspi_work);
+	spin_lock_init(&mcfqspi->lock);
+	INIT_LIST_HEAD(&mcfqspi->msgq);
+	init_waitqueue_head(&mcfqspi->waitq);
+
+	pdata = pdev->dev.platform_data;
+	if (!pdata) {
+		dev_dbg(&pdev->dev, "platform data is missing\n");
+		goto fail5;
+	}
+	master->bus_num = pdata->bus_num;
+	master->num_chipselect = pdata->num_chipselect;
+
+	mcfqspi->cs_control = pdata->cs_control;
+	status = mcfqspi_cs_setup(mcfqspi);
+	if (status) {
+		dev_dbg(&pdev->dev, "error initializing cs_control\n");
+		goto fail5;
+	}
+
+	master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
+	master->setup = mcfqspi_setup;
+	master->transfer = mcfqspi_transfer;
+
+	platform_set_drvdata(pdev, master);
+
+	status = spi_register_master(master);
+	if (status) {
+		dev_dbg(&pdev->dev, "spi_register_master failed\n");
+		goto fail6;
+	}
+	dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
+
+	return 0;
+
+fail6:
+	mcfqspi_cs_teardown(mcfqspi);
+fail5:
+	destroy_workqueue(mcfqspi->workq);
+fail4:
+	clk_disable(mcfqspi->clk);
+	clk_put(mcfqspi->clk);
+fail3:
+	free_irq(mcfqspi->irq, mcfqspi);
+fail2:
+	iounmap(mcfqspi->iobase);
+fail1:
+	release_mem_region(res->start, resource_size(res));
+fail0:
+	spi_master_put(master);
+
+	dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
+
+	return status;
+}
+
+static int __devexit mcfqspi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master = platform_get_drvdata(pdev);
+	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	/* disable the hardware (set the baud rate to 0) */
+	mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
+
+	platform_set_drvdata(pdev, NULL);
+	mcfqspi_cs_teardown(mcfqspi);
+	destroy_workqueue(mcfqspi->workq);
+	clk_disable(mcfqspi->clk);
+	clk_put(mcfqspi->clk);
+	free_irq(mcfqspi->irq, mcfqspi);
+	iounmap(mcfqspi->iobase);
+	release_mem_region(res->start, resource_size(res));
+	spi_unregister_master(master);
+	spi_master_put(master);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int mcfqspi_suspend(struct device *dev)
+{
+	struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
+
+	clk_disable(mcfqspi->clk);
+
+	return 0;
+}
+
+static int mcfqspi_resume(struct device *dev)
+{
+	struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
+
+	clk_enable(mcfqspi->clk);
+
+	return 0;
+}
+
+static struct dev_pm_ops mcfqspi_dev_pm_ops = {
+	.suspend	= mcfqspi_suspend,
+	.resume		= mcfqspi_resume,
+};
+
+#define	MCFQSPI_DEV_PM_OPS	(&mcfqspi_dev_pm_ops)
+#else
+#define	MCFQSPI_DEV_PM_OPS	NULL
+#endif
+
+static struct platform_driver mcfqspi_driver = {
+	.driver.name	= DRIVER_NAME,
+	.driver.owner	= THIS_MODULE,
+	.driver.pm	= MCFQSPI_DEV_PM_OPS,
+	.remove		= __devexit_p(mcfqspi_remove),
+};
+
+static int __init mcfqspi_init(void)
+{
+	return platform_driver_probe(&mcfqspi_driver, mcfqspi_probe);
+}
+module_init(mcfqspi_init);
+
+static void __exit mcfqspi_exit(void)
+{
+	platform_driver_unregister(&mcfqspi_driver);
+}
+module_exit(mcfqspi_exit);
+
+MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
+MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);