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authorGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
committerGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
commitca632f556697d45d67ed5cada7cedf3ddfe0db4b (patch)
treef393534b929abb32813ea5c495f1ac6d93a10d1d /drivers/spi/spi-fsl-spi.c
parent8c99268431a117207a89be5167ecd69429fd4bda (diff)
downloadlinux-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.tar.gz
spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.

This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.

v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
      be the predominant pattern for subsystem prefixes.
    - Clean up filenames in Kconfig and header comment blocks

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/spi/spi-fsl-spi.c')
-rw-r--r--drivers/spi/spi-fsl-spi.c1192
1 files changed, 1192 insertions, 0 deletions
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
new file mode 100644
index 000000000000..e013117a404d
--- /dev/null
+++ b/drivers/spi/spi-fsl-spi.c
@@ -0,0 +1,1192 @@
+/*
+ * Freescale SPI controller driver.
+ *
+ * Maintainer: Kumar Gala
+ *
+ * Copyright (C) 2006 Polycom, Inc.
+ * Copyright 2010 Freescale Semiconductor, Inc.
+ *
+ * CPM SPI and QE buffer descriptors mode support:
+ * Copyright (c) 2009  MontaVista Software, Inc.
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.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.
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/platform_device.h>
+#include <linux/fsl_devices.h>
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+
+#include <sysdev/fsl_soc.h>
+#include <asm/cpm.h>
+#include <asm/qe.h>
+
+#include "spi-fsl-lib.h"
+
+/* CPM1 and CPM2 are mutually exclusive. */
+#ifdef CONFIG_CPM1
+#include <asm/cpm1.h>
+#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_CH_SPI, 0)
+#else
+#include <asm/cpm2.h>
+#define CPM_SPI_CMD mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK, 0, 0)
+#endif
+
+/* SPI Controller registers */
+struct fsl_spi_reg {
+	u8 res1[0x20];
+	__be32 mode;
+	__be32 event;
+	__be32 mask;
+	__be32 command;
+	__be32 transmit;
+	__be32 receive;
+};
+
+/* SPI Controller mode register definitions */
+#define	SPMODE_LOOP		(1 << 30)
+#define	SPMODE_CI_INACTIVEHIGH	(1 << 29)
+#define	SPMODE_CP_BEGIN_EDGECLK	(1 << 28)
+#define	SPMODE_DIV16		(1 << 27)
+#define	SPMODE_REV		(1 << 26)
+#define	SPMODE_MS		(1 << 25)
+#define	SPMODE_ENABLE		(1 << 24)
+#define	SPMODE_LEN(x)		((x) << 20)
+#define	SPMODE_PM(x)		((x) << 16)
+#define	SPMODE_OP		(1 << 14)
+#define	SPMODE_CG(x)		((x) << 7)
+
+/*
+ * Default for SPI Mode:
+ *	SPI MODE 0 (inactive low, phase middle, MSB, 8-bit length, slow clk
+ */
+#define	SPMODE_INIT_VAL (SPMODE_CI_INACTIVEHIGH | SPMODE_DIV16 | SPMODE_REV | \
+			 SPMODE_MS | SPMODE_LEN(7) | SPMODE_PM(0xf))
+
+/* SPIE register values */
+#define	SPIE_NE		0x00000200	/* Not empty */
+#define	SPIE_NF		0x00000100	/* Not full */
+
+/* SPIM register values */
+#define	SPIM_NE		0x00000200	/* Not empty */
+#define	SPIM_NF		0x00000100	/* Not full */
+
+#define	SPIE_TXB	0x00000200	/* Last char is written to tx fifo */
+#define	SPIE_RXB	0x00000100	/* Last char is written to rx buf */
+
+/* SPCOM register values */
+#define	SPCOM_STR	(1 << 23)	/* Start transmit */
+
+#define	SPI_PRAM_SIZE	0x100
+#define	SPI_MRBLR	((unsigned int)PAGE_SIZE)
+
+static void *fsl_dummy_rx;
+static DEFINE_MUTEX(fsl_dummy_rx_lock);
+static int fsl_dummy_rx_refcnt;
+
+static void fsl_spi_change_mode(struct spi_device *spi)
+{
+	struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+	struct spi_mpc8xxx_cs *cs = spi->controller_state;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+	__be32 __iomem *mode = &reg_base->mode;
+	unsigned long flags;
+
+	if (cs->hw_mode == mpc8xxx_spi_read_reg(mode))
+		return;
+
+	/* Turn off IRQs locally to minimize time that SPI is disabled. */
+	local_irq_save(flags);
+
+	/* Turn off SPI unit prior changing mode */
+	mpc8xxx_spi_write_reg(mode, cs->hw_mode & ~SPMODE_ENABLE);
+
+	/* When in CPM mode, we need to reinit tx and rx. */
+	if (mspi->flags & SPI_CPM_MODE) {
+		if (mspi->flags & SPI_QE) {
+			qe_issue_cmd(QE_INIT_TX_RX, mspi->subblock,
+				     QE_CR_PROTOCOL_UNSPECIFIED, 0);
+		} else {
+			cpm_command(CPM_SPI_CMD, CPM_CR_INIT_TRX);
+			if (mspi->flags & SPI_CPM1) {
+				out_be16(&mspi->pram->rbptr,
+					 in_be16(&mspi->pram->rbase));
+				out_be16(&mspi->pram->tbptr,
+					 in_be16(&mspi->pram->tbase));
+			}
+		}
+	}
+	mpc8xxx_spi_write_reg(mode, cs->hw_mode);
+	local_irq_restore(flags);
+}
+
+static void fsl_spi_chipselect(struct spi_device *spi, int value)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	struct fsl_spi_platform_data *pdata = spi->dev.parent->platform_data;
+	bool pol = spi->mode & SPI_CS_HIGH;
+	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
+
+	if (value == BITBANG_CS_INACTIVE) {
+		if (pdata->cs_control)
+			pdata->cs_control(spi, !pol);
+	}
+
+	if (value == BITBANG_CS_ACTIVE) {
+		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;
+
+		fsl_spi_change_mode(spi);
+
+		if (pdata->cs_control)
+			pdata->cs_control(spi, pol);
+	}
+}
+
+static int mspi_apply_cpu_mode_quirks(struct spi_mpc8xxx_cs *cs,
+				struct spi_device *spi,
+				struct mpc8xxx_spi *mpc8xxx_spi,
+				int bits_per_word)
+{
+	cs->rx_shift = 0;
+	cs->tx_shift = 0;
+	if (bits_per_word <= 8) {
+		cs->get_rx = mpc8xxx_spi_rx_buf_u8;
+		cs->get_tx = mpc8xxx_spi_tx_buf_u8;
+		if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+			cs->rx_shift = 16;
+			cs->tx_shift = 24;
+		}
+	} else if (bits_per_word <= 16) {
+		cs->get_rx = mpc8xxx_spi_rx_buf_u16;
+		cs->get_tx = mpc8xxx_spi_tx_buf_u16;
+		if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+			cs->rx_shift = 16;
+			cs->tx_shift = 16;
+		}
+	} else if (bits_per_word <= 32) {
+		cs->get_rx = mpc8xxx_spi_rx_buf_u32;
+		cs->get_tx = mpc8xxx_spi_tx_buf_u32;
+	} else
+		return -EINVAL;
+
+	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE &&
+	    spi->mode & SPI_LSB_FIRST) {
+		cs->tx_shift = 0;
+		if (bits_per_word <= 8)
+			cs->rx_shift = 8;
+		else
+			cs->rx_shift = 0;
+	}
+	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;
+
+	return bits_per_word;
+}
+
+static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs,
+				struct spi_device *spi,
+				int bits_per_word)
+{
+	/* QE uses Little Endian for words > 8
+	 * so transform all words > 8 into 8 bits
+	 * Unfortnatly that doesn't work for LSB so
+	 * reject these for now */
+	/* Note: 32 bits word, LSB works iff
+	 * tfcr/rfcr is set to CPMFCR_GBL */
+	if (spi->mode & SPI_LSB_FIRST &&
+	    bits_per_word > 8)
+		return -EINVAL;
+	if (bits_per_word > 8)
+		return 8; /* pretend its 8 bits */
+	return bits_per_word;
+}
+
+static int fsl_spi_setup_transfer(struct spi_device *spi,
+					struct spi_transfer *t)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	int bits_per_word = 0;
+	u8 pm;
+	u32 hz = 0;
+	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
+
+	mpc8xxx_spi = spi_master_get_devdata(spi->master);
+
+	if (t) {
+		bits_per_word = t->bits_per_word;
+		hz = t->speed_hz;
+	}
+
+	/* spi_transfer level calls that work per-word */
+	if (!bits_per_word)
+		bits_per_word = spi->bits_per_word;
+
+	/* Make sure its a bit width we support [4..16, 32] */
+	if ((bits_per_word < 4)
+	    || ((bits_per_word > 16) && (bits_per_word != 32)))
+		return -EINVAL;
+
+	if (!hz)
+		hz = spi->max_speed_hz;
+
+	if (!(mpc8xxx_spi->flags & SPI_CPM_MODE))
+		bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi,
+							   mpc8xxx_spi,
+							   bits_per_word);
+	else if (mpc8xxx_spi->flags & SPI_QE)
+		bits_per_word = mspi_apply_qe_mode_quirks(cs, spi,
+							  bits_per_word);
+
+	if (bits_per_word < 0)
+		return bits_per_word;
+
+	if (bits_per_word == 32)
+		bits_per_word = 0;
+	else
+		bits_per_word = bits_per_word - 1;
+
+	/* mask out bits we are going to set */
+	cs->hw_mode &= ~(SPMODE_LEN(0xF) | SPMODE_DIV16
+				  | SPMODE_PM(0xF));
+
+	cs->hw_mode |= SPMODE_LEN(bits_per_word);
+
+	if ((mpc8xxx_spi->spibrg / hz) > 64) {
+		cs->hw_mode |= SPMODE_DIV16;
+		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
+
+		WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
+			  "Will use %d Hz instead.\n", dev_name(&spi->dev),
+			  hz, mpc8xxx_spi->spibrg / 1024);
+		if (pm > 16)
+			pm = 16;
+	} else {
+		pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
+	}
+	if (pm)
+		pm--;
+
+	cs->hw_mode |= SPMODE_PM(pm);
+
+	fsl_spi_change_mode(spi);
+	return 0;
+}
+
+static void fsl_spi_cpm_bufs_start(struct mpc8xxx_spi *mspi)
+{
+	struct cpm_buf_desc __iomem *tx_bd = mspi->tx_bd;
+	struct cpm_buf_desc __iomem *rx_bd = mspi->rx_bd;
+	unsigned int xfer_len = min(mspi->count, SPI_MRBLR);
+	unsigned int xfer_ofs;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	xfer_ofs = mspi->xfer_in_progress->len - mspi->count;
+
+	if (mspi->rx_dma == mspi->dma_dummy_rx)
+		out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma);
+	else
+		out_be32(&rx_bd->cbd_bufaddr, mspi->rx_dma + xfer_ofs);
+	out_be16(&rx_bd->cbd_datlen, 0);
+	out_be16(&rx_bd->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT | BD_SC_WRAP);
+
+	if (mspi->tx_dma == mspi->dma_dummy_tx)
+		out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma);
+	else
+		out_be32(&tx_bd->cbd_bufaddr, mspi->tx_dma + xfer_ofs);
+	out_be16(&tx_bd->cbd_datlen, xfer_len);
+	out_be16(&tx_bd->cbd_sc, BD_SC_READY | BD_SC_INTRPT | BD_SC_WRAP |
+				 BD_SC_LAST);
+
+	/* start transfer */
+	mpc8xxx_spi_write_reg(&reg_base->command, SPCOM_STR);
+}
+
+static int fsl_spi_cpm_bufs(struct mpc8xxx_spi *mspi,
+				struct spi_transfer *t, bool is_dma_mapped)
+{
+	struct device *dev = mspi->dev;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	if (is_dma_mapped) {
+		mspi->map_tx_dma = 0;
+		mspi->map_rx_dma = 0;
+	} else {
+		mspi->map_tx_dma = 1;
+		mspi->map_rx_dma = 1;
+	}
+
+	if (!t->tx_buf) {
+		mspi->tx_dma = mspi->dma_dummy_tx;
+		mspi->map_tx_dma = 0;
+	}
+
+	if (!t->rx_buf) {
+		mspi->rx_dma = mspi->dma_dummy_rx;
+		mspi->map_rx_dma = 0;
+	}
+
+	if (mspi->map_tx_dma) {
+		void *nonconst_tx = (void *)mspi->tx; /* shut up gcc */
+
+		mspi->tx_dma = dma_map_single(dev, nonconst_tx, t->len,
+					      DMA_TO_DEVICE);
+		if (dma_mapping_error(dev, mspi->tx_dma)) {
+			dev_err(dev, "unable to map tx dma\n");
+			return -ENOMEM;
+		}
+	} else if (t->tx_buf) {
+		mspi->tx_dma = t->tx_dma;
+	}
+
+	if (mspi->map_rx_dma) {
+		mspi->rx_dma = dma_map_single(dev, mspi->rx, t->len,
+					      DMA_FROM_DEVICE);
+		if (dma_mapping_error(dev, mspi->rx_dma)) {
+			dev_err(dev, "unable to map rx dma\n");
+			goto err_rx_dma;
+		}
+	} else if (t->rx_buf) {
+		mspi->rx_dma = t->rx_dma;
+	}
+
+	/* enable rx ints */
+	mpc8xxx_spi_write_reg(&reg_base->mask, SPIE_RXB);
+
+	mspi->xfer_in_progress = t;
+	mspi->count = t->len;
+
+	/* start CPM transfers */
+	fsl_spi_cpm_bufs_start(mspi);
+
+	return 0;
+
+err_rx_dma:
+	if (mspi->map_tx_dma)
+		dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
+	return -ENOMEM;
+}
+
+static void fsl_spi_cpm_bufs_complete(struct mpc8xxx_spi *mspi)
+{
+	struct device *dev = mspi->dev;
+	struct spi_transfer *t = mspi->xfer_in_progress;
+
+	if (mspi->map_tx_dma)
+		dma_unmap_single(dev, mspi->tx_dma, t->len, DMA_TO_DEVICE);
+	if (mspi->map_rx_dma)
+		dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE);
+	mspi->xfer_in_progress = NULL;
+}
+
+static int fsl_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
+				struct spi_transfer *t, unsigned int len)
+{
+	u32 word;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	mspi->count = len;
+
+	/* enable rx ints */
+	mpc8xxx_spi_write_reg(&reg_base->mask, SPIM_NE);
+
+	/* transmit word */
+	word = mspi->get_tx(mspi);
+	mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+
+	return 0;
+}
+
+static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t,
+			    bool is_dma_mapped)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+	struct fsl_spi_reg *reg_base;
+	unsigned int len = t->len;
+	u8 bits_per_word;
+	int ret;
+
+	reg_base = mpc8xxx_spi->reg_base;
+	bits_per_word = spi->bits_per_word;
+	if (t->bits_per_word)
+		bits_per_word = t->bits_per_word;
+
+	if (bits_per_word > 8) {
+		/* invalid length? */
+		if (len & 1)
+			return -EINVAL;
+		len /= 2;
+	}
+	if (bits_per_word > 16) {
+		/* invalid length? */
+		if (len & 1)
+			return -EINVAL;
+		len /= 2;
+	}
+
+	mpc8xxx_spi->tx = t->tx_buf;
+	mpc8xxx_spi->rx = t->rx_buf;
+
+	INIT_COMPLETION(mpc8xxx_spi->done);
+
+	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
+		ret = fsl_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
+	else
+		ret = fsl_spi_cpu_bufs(mpc8xxx_spi, t, len);
+	if (ret)
+		return ret;
+
+	wait_for_completion(&mpc8xxx_spi->done);
+
+	/* disable rx ints */
+	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+
+	if (mpc8xxx_spi->flags & SPI_CPM_MODE)
+		fsl_spi_cpm_bufs_complete(mpc8xxx_spi);
+
+	return mpc8xxx_spi->count;
+}
+
+static void fsl_spi_do_one_msg(struct spi_message *m)
+{
+	struct spi_device *spi = m->spi;
+	struct spi_transfer *t;
+	unsigned int cs_change;
+	const int nsecs = 50;
+	int status;
+
+	cs_change = 1;
+	status = 0;
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		if (t->bits_per_word || t->speed_hz) {
+			/* Don't allow changes if CS is active */
+			status = -EINVAL;
+
+			if (cs_change)
+				status = fsl_spi_setup_transfer(spi, t);
+			if (status < 0)
+				break;
+		}
+
+		if (cs_change) {
+			fsl_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+			ndelay(nsecs);
+		}
+		cs_change = t->cs_change;
+		if (t->len)
+			status = fsl_spi_bufs(spi, t, m->is_dma_mapped);
+		if (status) {
+			status = -EMSGSIZE;
+			break;
+		}
+		m->actual_length += t->len;
+
+		if (t->delay_usecs)
+			udelay(t->delay_usecs);
+
+		if (cs_change) {
+			ndelay(nsecs);
+			fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+			ndelay(nsecs);
+		}
+	}
+
+	m->status = status;
+	m->complete(m->context);
+
+	if (status || !cs_change) {
+		ndelay(nsecs);
+		fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE);
+	}
+
+	fsl_spi_setup_transfer(spi, NULL);
+}
+
+static int fsl_spi_setup(struct spi_device *spi)
+{
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_spi_reg *reg_base;
+	int retval;
+	u32 hw_mode;
+	struct spi_mpc8xxx_cs	*cs = spi->controller_state;
+
+	if (!spi->max_speed_hz)
+		return -EINVAL;
+
+	if (!cs) {
+		cs = kzalloc(sizeof *cs, GFP_KERNEL);
+		if (!cs)
+			return -ENOMEM;
+		spi->controller_state = cs;
+	}
+	mpc8xxx_spi = spi_master_get_devdata(spi->master);
+
+	reg_base = mpc8xxx_spi->reg_base;
+
+	hw_mode = cs->hw_mode; /* Save original settings */
+	cs->hw_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
+	/* mask out bits we are going to set */
+	cs->hw_mode &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
+			 | SPMODE_REV | SPMODE_LOOP);
+
+	if (spi->mode & SPI_CPHA)
+		cs->hw_mode |= SPMODE_CP_BEGIN_EDGECLK;
+	if (spi->mode & SPI_CPOL)
+		cs->hw_mode |= SPMODE_CI_INACTIVEHIGH;
+	if (!(spi->mode & SPI_LSB_FIRST))
+		cs->hw_mode |= SPMODE_REV;
+	if (spi->mode & SPI_LOOP)
+		cs->hw_mode |= SPMODE_LOOP;
+
+	retval = fsl_spi_setup_transfer(spi, NULL);
+	if (retval < 0) {
+		cs->hw_mode = hw_mode; /* Restore settings */
+		return retval;
+	}
+	return 0;
+}
+
+static void fsl_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+	u16 len;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	dev_dbg(mspi->dev, "%s: bd datlen %d, count %d\n", __func__,
+		in_be16(&mspi->rx_bd->cbd_datlen), mspi->count);
+
+	len = in_be16(&mspi->rx_bd->cbd_datlen);
+	if (len > mspi->count) {
+		WARN_ON(1);
+		len = mspi->count;
+	}
+
+	/* Clear the events */
+	mpc8xxx_spi_write_reg(&reg_base->event, events);
+
+	mspi->count -= len;
+	if (mspi->count)
+		fsl_spi_cpm_bufs_start(mspi);
+	else
+		complete(&mspi->done);
+}
+
+static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	/* We need handle RX first */
+	if (events & SPIE_NE) {
+		u32 rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
+
+		if (mspi->rx)
+			mspi->get_rx(rx_data, mspi);
+	}
+
+	if ((events & SPIE_NF) == 0)
+		/* spin until TX is done */
+		while (((events =
+			mpc8xxx_spi_read_reg(&reg_base->event)) &
+						SPIE_NF) == 0)
+			cpu_relax();
+
+	/* Clear the events */
+	mpc8xxx_spi_write_reg(&reg_base->event, events);
+
+	mspi->count -= 1;
+	if (mspi->count) {
+		u32 word = mspi->get_tx(mspi);
+
+		mpc8xxx_spi_write_reg(&reg_base->transmit, word);
+	} else {
+		complete(&mspi->done);
+	}
+}
+
+static irqreturn_t fsl_spi_irq(s32 irq, void *context_data)
+{
+	struct mpc8xxx_spi *mspi = context_data;
+	irqreturn_t ret = IRQ_NONE;
+	u32 events;
+	struct fsl_spi_reg *reg_base = mspi->reg_base;
+
+	/* Get interrupt events(tx/rx) */
+	events = mpc8xxx_spi_read_reg(&reg_base->event);
+	if (events)
+		ret = IRQ_HANDLED;
+
+	dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
+
+	if (mspi->flags & SPI_CPM_MODE)
+		fsl_spi_cpm_irq(mspi, events);
+	else
+		fsl_spi_cpu_irq(mspi, events);
+
+	return ret;
+}
+
+static void *fsl_spi_alloc_dummy_rx(void)
+{
+	mutex_lock(&fsl_dummy_rx_lock);
+
+	if (!fsl_dummy_rx)
+		fsl_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL);
+	if (fsl_dummy_rx)
+		fsl_dummy_rx_refcnt++;
+
+	mutex_unlock(&fsl_dummy_rx_lock);
+
+	return fsl_dummy_rx;
+}
+
+static void fsl_spi_free_dummy_rx(void)
+{
+	mutex_lock(&fsl_dummy_rx_lock);
+
+	switch (fsl_dummy_rx_refcnt) {
+	case 0:
+		WARN_ON(1);
+		break;
+	case 1:
+		kfree(fsl_dummy_rx);
+		fsl_dummy_rx = NULL;
+		/* fall through */
+	default:
+		fsl_dummy_rx_refcnt--;
+		break;
+	}
+
+	mutex_unlock(&fsl_dummy_rx_lock);
+}
+
+static unsigned long fsl_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
+{
+	struct device *dev = mspi->dev;
+	struct device_node *np = dev->of_node;
+	const u32 *iprop;
+	int size;
+	unsigned long spi_base_ofs;
+	unsigned long pram_ofs = -ENOMEM;
+
+	/* Can't use of_address_to_resource(), QE muram isn't at 0. */
+	iprop = of_get_property(np, "reg", &size);
+
+	/* QE with a fixed pram location? */
+	if (mspi->flags & SPI_QE && iprop && size == sizeof(*iprop) * 4)
+		return cpm_muram_alloc_fixed(iprop[2], SPI_PRAM_SIZE);
+
+	/* QE but with a dynamic pram location? */
+	if (mspi->flags & SPI_QE) {
+		pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
+		qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, mspi->subblock,
+				QE_CR_PROTOCOL_UNSPECIFIED, pram_ofs);
+		return pram_ofs;
+	}
+
+	/* CPM1 and CPM2 pram must be at a fixed addr. */
+	if (!iprop || size != sizeof(*iprop) * 4)
+		return -ENOMEM;
+
+	spi_base_ofs = cpm_muram_alloc_fixed(iprop[2], 2);
+	if (IS_ERR_VALUE(spi_base_ofs))
+		return -ENOMEM;
+
+	if (mspi->flags & SPI_CPM2) {
+		pram_ofs = cpm_muram_alloc(SPI_PRAM_SIZE, 64);
+		if (!IS_ERR_VALUE(pram_ofs)) {
+			u16 __iomem *spi_base = cpm_muram_addr(spi_base_ofs);
+
+			out_be16(spi_base, pram_ofs);
+		}
+	} else {
+		struct spi_pram __iomem *pram = cpm_muram_addr(spi_base_ofs);
+		u16 rpbase = in_be16(&pram->rpbase);
+
+		/* Microcode relocation patch applied? */
+		if (rpbase)
+			pram_ofs = rpbase;
+		else
+			return spi_base_ofs;
+	}
+
+	cpm_muram_free(spi_base_ofs);
+	return pram_ofs;
+}
+
+static int fsl_spi_cpm_init(struct mpc8xxx_spi *mspi)
+{
+	struct device *dev = mspi->dev;
+	struct device_node *np = dev->of_node;
+	const u32 *iprop;
+	int size;
+	unsigned long pram_ofs;
+	unsigned long bds_ofs;
+
+	if (!(mspi->flags & SPI_CPM_MODE))
+		return 0;
+
+	if (!fsl_spi_alloc_dummy_rx())
+		return -ENOMEM;
+
+	if (mspi->flags & SPI_QE) {
+		iprop = of_get_property(np, "cell-index", &size);
+		if (iprop && size == sizeof(*iprop))
+			mspi->subblock = *iprop;
+
+		switch (mspi->subblock) {
+		default:
+			dev_warn(dev, "cell-index unspecified, assuming SPI1");
+			/* fall through */
+		case 0:
+			mspi->subblock = QE_CR_SUBBLOCK_SPI1;
+			break;
+		case 1:
+			mspi->subblock = QE_CR_SUBBLOCK_SPI2;
+			break;
+		}
+	}
+
+	pram_ofs = fsl_spi_cpm_get_pram(mspi);
+	if (IS_ERR_VALUE(pram_ofs)) {
+		dev_err(dev, "can't allocate spi parameter ram\n");
+		goto err_pram;
+	}
+
+	bds_ofs = cpm_muram_alloc(sizeof(*mspi->tx_bd) +
+				  sizeof(*mspi->rx_bd), 8);
+	if (IS_ERR_VALUE(bds_ofs)) {
+		dev_err(dev, "can't allocate bds\n");
+		goto err_bds;
+	}
+
+	mspi->dma_dummy_tx = dma_map_single(dev, empty_zero_page, PAGE_SIZE,
+					    DMA_TO_DEVICE);
+	if (dma_mapping_error(dev, mspi->dma_dummy_tx)) {
+		dev_err(dev, "unable to map dummy tx buffer\n");
+		goto err_dummy_tx;
+	}
+
+	mspi->dma_dummy_rx = dma_map_single(dev, fsl_dummy_rx, SPI_MRBLR,
+					    DMA_FROM_DEVICE);
+	if (dma_mapping_error(dev, mspi->dma_dummy_rx)) {
+		dev_err(dev, "unable to map dummy rx buffer\n");
+		goto err_dummy_rx;
+	}
+
+	mspi->pram = cpm_muram_addr(pram_ofs);
+
+	mspi->tx_bd = cpm_muram_addr(bds_ofs);
+	mspi->rx_bd = cpm_muram_addr(bds_ofs + sizeof(*mspi->tx_bd));
+
+	/* Initialize parameter ram. */
+	out_be16(&mspi->pram->tbase, cpm_muram_offset(mspi->tx_bd));
+	out_be16(&mspi->pram->rbase, cpm_muram_offset(mspi->rx_bd));
+	out_8(&mspi->pram->tfcr, CPMFCR_EB | CPMFCR_GBL);
+	out_8(&mspi->pram->rfcr, CPMFCR_EB | CPMFCR_GBL);
+	out_be16(&mspi->pram->mrblr, SPI_MRBLR);
+	out_be32(&mspi->pram->rstate, 0);
+	out_be32(&mspi->pram->rdp, 0);
+	out_be16(&mspi->pram->rbptr, 0);
+	out_be16(&mspi->pram->rbc, 0);
+	out_be32(&mspi->pram->rxtmp, 0);
+	out_be32(&mspi->pram->tstate, 0);
+	out_be32(&mspi->pram->tdp, 0);
+	out_be16(&mspi->pram->tbptr, 0);
+	out_be16(&mspi->pram->tbc, 0);
+	out_be32(&mspi->pram->txtmp, 0);
+
+	return 0;
+
+err_dummy_rx:
+	dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
+err_dummy_tx:
+	cpm_muram_free(bds_ofs);
+err_bds:
+	cpm_muram_free(pram_ofs);
+err_pram:
+	fsl_spi_free_dummy_rx();
+	return -ENOMEM;
+}
+
+static void fsl_spi_cpm_free(struct mpc8xxx_spi *mspi)
+{
+	struct device *dev = mspi->dev;
+
+	dma_unmap_single(dev, mspi->dma_dummy_rx, SPI_MRBLR, DMA_FROM_DEVICE);
+	dma_unmap_single(dev, mspi->dma_dummy_tx, PAGE_SIZE, DMA_TO_DEVICE);
+	cpm_muram_free(cpm_muram_offset(mspi->tx_bd));
+	cpm_muram_free(cpm_muram_offset(mspi->pram));
+	fsl_spi_free_dummy_rx();
+}
+
+static void fsl_spi_remove(struct mpc8xxx_spi *mspi)
+{
+	iounmap(mspi->reg_base);
+	fsl_spi_cpm_free(mspi);
+}
+
+static struct spi_master * __devinit fsl_spi_probe(struct device *dev,
+		struct resource *mem, unsigned int irq)
+{
+	struct fsl_spi_platform_data *pdata = dev->platform_data;
+	struct spi_master *master;
+	struct mpc8xxx_spi *mpc8xxx_spi;
+	struct fsl_spi_reg *reg_base;
+	u32 regval;
+	int ret = 0;
+
+	master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
+	if (master == NULL) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	dev_set_drvdata(dev, master);
+
+	ret = mpc8xxx_spi_probe(dev, mem, irq);
+	if (ret)
+		goto err_probe;
+
+	master->setup = fsl_spi_setup;
+
+	mpc8xxx_spi = spi_master_get_devdata(master);
+	mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg;
+	mpc8xxx_spi->spi_remove = fsl_spi_remove;
+
+
+	ret = fsl_spi_cpm_init(mpc8xxx_spi);
+	if (ret)
+		goto err_cpm_init;
+
+	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+		mpc8xxx_spi->rx_shift = 16;
+		mpc8xxx_spi->tx_shift = 24;
+	}
+
+	mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
+	if (mpc8xxx_spi->reg_base == NULL) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
+
+	/* Register for SPI Interrupt */
+	ret = request_irq(mpc8xxx_spi->irq, fsl_spi_irq,
+			  0, "fsl_spi", mpc8xxx_spi);
+
+	if (ret != 0)
+		goto free_irq;
+
+	reg_base = mpc8xxx_spi->reg_base;
+
+	/* SPI controller initializations */
+	mpc8xxx_spi_write_reg(&reg_base->mode, 0);
+	mpc8xxx_spi_write_reg(&reg_base->mask, 0);
+	mpc8xxx_spi_write_reg(&reg_base->command, 0);
+	mpc8xxx_spi_write_reg(&reg_base->event, 0xffffffff);
+
+	/* Enable SPI interface */
+	regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+	if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE)
+		regval |= SPMODE_OP;
+
+	mpc8xxx_spi_write_reg(&reg_base->mode, regval);
+
+	ret = spi_register_master(master);
+	if (ret < 0)
+		goto unreg_master;
+
+	dev_info(dev, "at 0x%p (irq = %d), %s mode\n", reg_base,
+		 mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
+
+	return master;
+
+unreg_master:
+	free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
+free_irq:
+	iounmap(mpc8xxx_spi->reg_base);
+err_ioremap:
+	fsl_spi_cpm_free(mpc8xxx_spi);
+err_cpm_init:
+err_probe:
+	spi_master_put(master);
+err:
+	return ERR_PTR(ret);
+}
+
+static void fsl_spi_cs_control(struct spi_device *spi, bool on)
+{
+	struct device *dev = spi->dev.parent;
+	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
+	u16 cs = spi->chip_select;
+	int gpio = pinfo->gpios[cs];
+	bool alow = pinfo->alow_flags[cs];
+
+	gpio_set_value(gpio, on ^ alow);
+}
+
+static int of_fsl_spi_get_chipselects(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct fsl_spi_platform_data *pdata = dev->platform_data;
+	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+	unsigned int ngpios;
+	int i = 0;
+	int ret;
+
+	ngpios = of_gpio_count(np);
+	if (!ngpios) {
+		/*
+		 * SPI w/o chip-select line. One SPI device is still permitted
+		 * though.
+		 */
+		pdata->max_chipselect = 1;
+		return 0;
+	}
+
+	pinfo->gpios = kmalloc(ngpios * sizeof(*pinfo->gpios), GFP_KERNEL);
+	if (!pinfo->gpios)
+		return -ENOMEM;
+	memset(pinfo->gpios, -1, ngpios * sizeof(*pinfo->gpios));
+
+	pinfo->alow_flags = kzalloc(ngpios * sizeof(*pinfo->alow_flags),
+				    GFP_KERNEL);
+	if (!pinfo->alow_flags) {
+		ret = -ENOMEM;
+		goto err_alloc_flags;
+	}
+
+	for (; i < ngpios; i++) {
+		int gpio;
+		enum of_gpio_flags flags;
+
+		gpio = of_get_gpio_flags(np, i, &flags);
+		if (!gpio_is_valid(gpio)) {
+			dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
+			ret = gpio;
+			goto err_loop;
+		}
+
+		ret = gpio_request(gpio, dev_name(dev));
+		if (ret) {
+			dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
+			goto err_loop;
+		}
+
+		pinfo->gpios[i] = gpio;
+		pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
+
+		ret = gpio_direction_output(pinfo->gpios[i],
+					    pinfo->alow_flags[i]);
+		if (ret) {
+			dev_err(dev, "can't set output direction for gpio "
+				"#%d: %d\n", i, ret);
+			goto err_loop;
+		}
+	}
+
+	pdata->max_chipselect = ngpios;
+	pdata->cs_control = fsl_spi_cs_control;
+
+	return 0;
+
+err_loop:
+	while (i >= 0) {
+		if (gpio_is_valid(pinfo->gpios[i]))
+			gpio_free(pinfo->gpios[i]);
+		i--;
+	}
+
+	kfree(pinfo->alow_flags);
+	pinfo->alow_flags = NULL;
+err_alloc_flags:
+	kfree(pinfo->gpios);
+	pinfo->gpios = NULL;
+	return ret;
+}
+
+static int of_fsl_spi_free_chipselects(struct device *dev)
+{
+	struct fsl_spi_platform_data *pdata = dev->platform_data;
+	struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+	int i;
+
+	if (!pinfo->gpios)
+		return 0;
+
+	for (i = 0; i < pdata->max_chipselect; i++) {
+		if (gpio_is_valid(pinfo->gpios[i]))
+			gpio_free(pinfo->gpios[i]);
+	}
+
+	kfree(pinfo->gpios);
+	kfree(pinfo->alow_flags);
+	return 0;
+}
+
+static int __devinit of_fsl_spi_probe(struct platform_device *ofdev)
+{
+	struct device *dev = &ofdev->dev;
+	struct device_node *np = ofdev->dev.of_node;
+	struct spi_master *master;
+	struct resource mem;
+	struct resource irq;
+	int ret = -ENOMEM;
+
+	ret = of_mpc8xxx_spi_probe(ofdev);
+	if (ret)
+		return ret;
+
+	ret = of_fsl_spi_get_chipselects(dev);
+	if (ret)
+		goto err;
+
+	ret = of_address_to_resource(np, 0, &mem);
+	if (ret)
+		goto err;
+
+	ret = of_irq_to_resource(np, 0, &irq);
+	if (!ret) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	master = fsl_spi_probe(dev, &mem, irq.start);
+	if (IS_ERR(master)) {
+		ret = PTR_ERR(master);
+		goto err;
+	}
+
+	return 0;
+
+err:
+	of_fsl_spi_free_chipselects(dev);
+	return ret;
+}
+
+static int __devexit of_fsl_spi_remove(struct platform_device *ofdev)
+{
+	int ret;
+
+	ret = mpc8xxx_spi_remove(&ofdev->dev);
+	if (ret)
+		return ret;
+	of_fsl_spi_free_chipselects(&ofdev->dev);
+	return 0;
+}
+
+static const struct of_device_id of_fsl_spi_match[] = {
+	{ .compatible = "fsl,spi" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, of_fsl_spi_match);
+
+static struct platform_driver of_fsl_spi_driver = {
+	.driver = {
+		.name = "fsl_spi",
+		.owner = THIS_MODULE,
+		.of_match_table = of_fsl_spi_match,
+	},
+	.probe		= of_fsl_spi_probe,
+	.remove		= __devexit_p(of_fsl_spi_remove),
+};
+
+#ifdef CONFIG_MPC832x_RDB
+/*
+ * XXX XXX XXX
+ * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
+ * only. The driver should go away soon, since newer MPC8323E-RDB's device
+ * tree can work with OpenFirmware driver. But for now we support old trees
+ * as well.
+ */
+static int __devinit plat_mpc8xxx_spi_probe(struct platform_device *pdev)
+{
+	struct resource *mem;
+	int irq;
+	struct spi_master *master;
+
+	if (!pdev->dev.platform_data)
+		return -EINVAL;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem)
+		return -EINVAL;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	master = fsl_spi_probe(&pdev->dev, mem, irq);
+	if (IS_ERR(master))
+		return PTR_ERR(master);
+	return 0;
+}
+
+static int __devexit plat_mpc8xxx_spi_remove(struct platform_device *pdev)
+{
+	return mpc8xxx_spi_remove(&pdev->dev);
+}
+
+MODULE_ALIAS("platform:mpc8xxx_spi");
+static struct platform_driver mpc8xxx_spi_driver = {
+	.probe = plat_mpc8xxx_spi_probe,
+	.remove = __devexit_p(plat_mpc8xxx_spi_remove),
+	.driver = {
+		.name = "mpc8xxx_spi",
+		.owner = THIS_MODULE,
+	},
+};
+
+static bool legacy_driver_failed;
+
+static void __init legacy_driver_register(void)
+{
+	legacy_driver_failed = platform_driver_register(&mpc8xxx_spi_driver);
+}
+
+static void __exit legacy_driver_unregister(void)
+{
+	if (legacy_driver_failed)
+		return;
+	platform_driver_unregister(&mpc8xxx_spi_driver);
+}
+#else
+static void __init legacy_driver_register(void) {}
+static void __exit legacy_driver_unregister(void) {}
+#endif /* CONFIG_MPC832x_RDB */
+
+static int __init fsl_spi_init(void)
+{
+	legacy_driver_register();
+	return platform_driver_register(&of_fsl_spi_driver);
+}
+module_init(fsl_spi_init);
+
+static void __exit fsl_spi_exit(void)
+{
+	platform_driver_unregister(&of_fsl_spi_driver);
+	legacy_driver_unregister();
+}
+module_exit(fsl_spi_exit);
+
+MODULE_AUTHOR("Kumar Gala");
+MODULE_DESCRIPTION("Simple Freescale SPI Driver");
+MODULE_LICENSE("GPL");