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path: root/drivers/spi/spi-fsl-espi.c
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Diffstat (limited to 'drivers/spi/spi-fsl-espi.c')
-rw-r--r--drivers/spi/spi-fsl-espi.c762
1 files changed, 762 insertions, 0 deletions
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
new file mode 100644
index 000000000000..54e499d5f92c
--- /dev/null
+++ b/drivers/spi/spi-fsl-espi.c
@@ -0,0 +1,762 @@
+/*
+ * Freescale eSPI controller driver.
+ *
+ * Copyright 2010 Freescale Semiconductor, Inc.
+ *
+ * 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/delay.h>
+#include <linux/irq.h>
+#include <linux/spi/spi.h>
+#include <linux/platform_device.h>
+#include <linux/fsl_devices.h>
+#include <linux/mm.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_spi.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <sysdev/fsl_soc.h>
+
+#include "spi-fsl-lib.h"
+
+/* eSPI Controller registers */
+struct fsl_espi_reg {
+ __be32 mode; /* 0x000 - eSPI mode register */
+ __be32 event; /* 0x004 - eSPI event register */
+ __be32 mask; /* 0x008 - eSPI mask register */
+ __be32 command; /* 0x00c - eSPI command register */
+ __be32 transmit; /* 0x010 - eSPI transmit FIFO access register*/
+ __be32 receive; /* 0x014 - eSPI receive FIFO access register*/
+ u8 res[8]; /* 0x018 - 0x01c reserved */
+ __be32 csmode[4]; /* 0x020 - 0x02c eSPI cs mode register */
+};
+
+struct fsl_espi_transfer {
+ const void *tx_buf;
+ void *rx_buf;
+ unsigned len;
+ unsigned n_tx;
+ unsigned n_rx;
+ unsigned actual_length;
+ int status;
+};
+
+/* eSPI Controller mode register definitions */
+#define SPMODE_ENABLE (1 << 31)
+#define SPMODE_LOOP (1 << 30)
+#define SPMODE_TXTHR(x) ((x) << 8)
+#define SPMODE_RXTHR(x) ((x) << 0)
+
+/* eSPI Controller CS mode register definitions */
+#define CSMODE_CI_INACTIVEHIGH (1 << 31)
+#define CSMODE_CP_BEGIN_EDGECLK (1 << 30)
+#define CSMODE_REV (1 << 29)
+#define CSMODE_DIV16 (1 << 28)
+#define CSMODE_PM(x) ((x) << 24)
+#define CSMODE_POL_1 (1 << 20)
+#define CSMODE_LEN(x) ((x) << 16)
+#define CSMODE_BEF(x) ((x) << 12)
+#define CSMODE_AFT(x) ((x) << 8)
+#define CSMODE_CG(x) ((x) << 3)
+
+/* Default mode/csmode for eSPI controller */
+#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(3))
+#define CSMODE_INIT_VAL (CSMODE_POL_1 | CSMODE_BEF(0) \
+ | CSMODE_AFT(0) | CSMODE_CG(1))
+
+/* 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_RXCNT(reg) ((reg >> 24) & 0x3F)
+#define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F)
+
+/* SPCOM register values */
+#define SPCOM_CS(x) ((x) << 30)
+#define SPCOM_TRANLEN(x) ((x) << 0)
+#define SPCOM_TRANLEN_MAX 0xFFFF /* Max transaction length */
+
+static void fsl_espi_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_espi_reg *reg_base = mspi->reg_base;
+ __be32 __iomem *mode = &reg_base->csmode[spi->chip_select];
+ __be32 __iomem *espi_mode = &reg_base->mode;
+ 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 = mpc8xxx_spi_read_reg(espi_mode);
+ mpc8xxx_spi_write_reg(espi_mode, tmp & ~SPMODE_ENABLE);
+ mpc8xxx_spi_write_reg(mode, cs->hw_mode);
+ mpc8xxx_spi_write_reg(espi_mode, tmp);
+
+ local_irq_restore(flags);
+}
+
+static u32 fsl_espi_tx_buf_lsb(struct mpc8xxx_spi *mpc8xxx_spi)
+{
+ u32 data;
+ u16 data_h;
+ u16 data_l;
+ const u32 *tx = mpc8xxx_spi->tx;
+
+ if (!tx)
+ return 0;
+
+ 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;
+
+ mpc8xxx_spi->tx = tx;
+ return data;
+}
+
+static int fsl_espi_setup_transfer(struct spi_device *spi,
+ struct spi_transfer *t)
+{
+ struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+ int bits_per_word = 0;
+ u8 pm;
+ u32 hz = 0;
+ struct spi_mpc8xxx_cs *cs = spi->controller_state;
+
+ 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] */
+ if ((bits_per_word < 4) || (bits_per_word > 16))
+ return -EINVAL;
+
+ if (!hz)
+ hz = spi->max_speed_hz;
+
+ 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 if (bits_per_word <= 16) {
+ cs->rx_shift = 16 - bits_per_word;
+ if (spi->mode & SPI_LSB_FIRST)
+ cs->get_tx = fsl_espi_tx_buf_lsb;
+ } else {
+ return -EINVAL;
+ }
+
+ 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;
+
+ bits_per_word = bits_per_word - 1;
+
+ /* 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);
+
+ if ((mpc8xxx_spi->spibrg / hz) > 64) {
+ cs->hw_mode |= CSMODE_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 |= CSMODE_PM(pm);
+
+ fsl_espi_change_mode(spi);
+ return 0;
+}
+
+static int fsl_espi_cpu_bufs(struct mpc8xxx_spi *mspi, struct spi_transfer *t,
+ unsigned int len)
+{
+ u32 word;
+ struct fsl_espi_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_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
+{
+ struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
+ struct fsl_espi_reg *reg_base = mpc8xxx_spi->reg_base;
+ unsigned int len = t->len;
+ u8 bits_per_word;
+ int ret;
+
+ bits_per_word = spi->bits_per_word;
+ if (t->bits_per_word)
+ bits_per_word = t->bits_per_word;
+
+ mpc8xxx_spi->len = t->len;
+ len = roundup(len, 4) / 4;
+
+ mpc8xxx_spi->tx = t->tx_buf;
+ mpc8xxx_spi->rx = t->rx_buf;
+
+ INIT_COMPLETION(mpc8xxx_spi->done);
+
+ /* Set SPCOM[CS] and SPCOM[TRANLEN] field */
+ if ((t->len - 1) > SPCOM_TRANLEN_MAX) {
+ dev_err(mpc8xxx_spi->dev, "Transaction length (%d)"
+ " beyond the SPCOM[TRANLEN] field\n", t->len);
+ return -EINVAL;
+ }
+ mpc8xxx_spi_write_reg(&reg_base->command,
+ (SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
+
+ ret = fsl_espi_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);
+
+ return mpc8xxx_spi->count;
+}
+
+static inline void fsl_espi_addr2cmd(unsigned int addr, u8 *cmd)
+{
+ if (cmd) {
+ cmd[1] = (u8)(addr >> 16);
+ cmd[2] = (u8)(addr >> 8);
+ cmd[3] = (u8)(addr >> 0);
+ }
+}
+
+static inline unsigned int fsl_espi_cmd2addr(u8 *cmd)
+{
+ if (cmd)
+ return cmd[1] << 16 | cmd[2] << 8 | cmd[3] << 0;
+
+ return 0;
+}
+
+static void fsl_espi_do_trans(struct spi_message *m,
+ struct fsl_espi_transfer *tr)
+{
+ struct spi_device *spi = m->spi;
+ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+ struct fsl_espi_transfer *espi_trans = tr;
+ struct spi_message message;
+ struct spi_transfer *t, *first, trans;
+ int status = 0;
+
+ spi_message_init(&message);
+ memset(&trans, 0, sizeof(trans));
+
+ 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)) {
+ espi_trans->status = -EINVAL;
+ dev_err(mspi->dev, "bits_per_word/speed_hz should be"
+ " same for the same SPI transfer\n");
+ return;
+ }
+
+ trans.speed_hz = t->speed_hz;
+ trans.bits_per_word = t->bits_per_word;
+ trans.delay_usecs = max(first->delay_usecs, t->delay_usecs);
+ }
+
+ trans.len = espi_trans->len;
+ trans.tx_buf = espi_trans->tx_buf;
+ trans.rx_buf = espi_trans->rx_buf;
+ spi_message_add_tail(&trans, &message);
+
+ list_for_each_entry(t, &message.transfers, transfer_list) {
+ if (t->bits_per_word || t->speed_hz) {
+ status = -EINVAL;
+
+ status = fsl_espi_setup_transfer(spi, t);
+ if (status < 0)
+ break;
+ }
+
+ if (t->len)
+ status = fsl_espi_bufs(spi, t);
+
+ if (status) {
+ status = -EMSGSIZE;
+ break;
+ }
+
+ if (t->delay_usecs)
+ udelay(t->delay_usecs);
+ }
+
+ espi_trans->status = status;
+ fsl_espi_setup_transfer(spi, NULL);
+}
+
+static void fsl_espi_cmd_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+{
+ struct spi_transfer *t;
+ u8 *local_buf;
+ int i = 0;
+ struct fsl_espi_transfer *espi_trans = trans;
+
+ local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+ if (!local_buf) {
+ espi_trans->status = -ENOMEM;
+ return;
+ }
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->tx_buf) {
+ memcpy(local_buf + i, t->tx_buf, t->len);
+ i += t->len;
+ }
+ }
+
+ espi_trans->tx_buf = local_buf;
+ espi_trans->rx_buf = local_buf + espi_trans->n_tx;
+ fsl_espi_do_trans(m, espi_trans);
+
+ espi_trans->actual_length = espi_trans->len;
+ kfree(local_buf);
+}
+
+static void fsl_espi_rw_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+{
+ struct fsl_espi_transfer *espi_trans = trans;
+ unsigned int n_tx = espi_trans->n_tx;
+ unsigned int n_rx = espi_trans->n_rx;
+ struct spi_transfer *t;
+ u8 *local_buf;
+ u8 *rx_buf = rx_buff;
+ unsigned int trans_len;
+ unsigned int addr;
+ int i, pos, loop;
+
+ local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+ if (!local_buf) {
+ espi_trans->status = -ENOMEM;
+ return;
+ }
+
+ for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) {
+ trans_len = n_rx - pos;
+ if (trans_len > SPCOM_TRANLEN_MAX - n_tx)
+ trans_len = SPCOM_TRANLEN_MAX - n_tx;
+
+ i = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->tx_buf) {
+ memcpy(local_buf + i, t->tx_buf, t->len);
+ i += t->len;
+ }
+ }
+
+ if (pos > 0) {
+ addr = fsl_espi_cmd2addr(local_buf);
+ addr += pos;
+ fsl_espi_addr2cmd(addr, local_buf);
+ }
+
+ espi_trans->n_tx = n_tx;
+ espi_trans->n_rx = trans_len;
+ espi_trans->len = trans_len + n_tx;
+ espi_trans->tx_buf = local_buf;
+ espi_trans->rx_buf = local_buf + n_tx;
+ fsl_espi_do_trans(m, espi_trans);
+
+ memcpy(rx_buf + pos, espi_trans->rx_buf + n_tx, trans_len);
+
+ if (loop > 0)
+ espi_trans->actual_length += espi_trans->len - n_tx;
+ else
+ espi_trans->actual_length += espi_trans->len;
+ }
+
+ kfree(local_buf);
+}
+
+static void fsl_espi_do_one_msg(struct spi_message *m)
+{
+ struct spi_transfer *t;
+ u8 *rx_buf = NULL;
+ unsigned int n_tx = 0;
+ unsigned int n_rx = 0;
+ struct fsl_espi_transfer espi_trans;
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->tx_buf)
+ n_tx += t->len;
+ if (t->rx_buf) {
+ n_rx += t->len;
+ rx_buf = t->rx_buf;
+ }
+ }
+
+ espi_trans.n_tx = n_tx;
+ espi_trans.n_rx = n_rx;
+ espi_trans.len = n_tx + n_rx;
+ espi_trans.actual_length = 0;
+ espi_trans.status = 0;
+
+ if (!rx_buf)
+ fsl_espi_cmd_trans(m, &espi_trans, NULL);
+ else
+ fsl_espi_rw_trans(m, &espi_trans, rx_buf);
+
+ m->actual_length = espi_trans.actual_length;
+ m->status = espi_trans.status;
+ m->complete(m->context);
+}
+
+static int fsl_espi_setup(struct spi_device *spi)
+{
+ struct mpc8xxx_spi *mpc8xxx_spi;
+ struct fsl_espi_reg *reg_base;
+ int retval;
+ u32 hw_mode;
+ u32 loop_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->csmode[spi->chip_select]);
+ /* mask out bits we are going to set */
+ cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
+ | CSMODE_REV);
+
+ if (spi->mode & SPI_CPHA)
+ cs->hw_mode |= CSMODE_CP_BEGIN_EDGECLK;
+ if (spi->mode & SPI_CPOL)
+ cs->hw_mode |= CSMODE_CI_INACTIVEHIGH;
+ if (!(spi->mode & SPI_LSB_FIRST))
+ cs->hw_mode |= CSMODE_REV;
+
+ /* Handle the loop mode */
+ loop_mode = mpc8xxx_spi_read_reg(&reg_base->mode);
+ loop_mode &= ~SPMODE_LOOP;
+ if (spi->mode & SPI_LOOP)
+ loop_mode |= SPMODE_LOOP;
+ mpc8xxx_spi_write_reg(&reg_base->mode, loop_mode);
+
+ retval = fsl_espi_setup_transfer(spi, NULL);
+ if (retval < 0) {
+ cs->hw_mode = hw_mode; /* Restore settings */
+ return retval;
+ }
+ return 0;
+}
+
+void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
+{
+ struct fsl_espi_reg *reg_base = mspi->reg_base;
+
+ /* We need handle RX first */
+ if (events & SPIE_NE) {
+ u32 rx_data, tmp;
+ u8 rx_data_8;
+
+ /* Spin until RX is done */
+ while (SPIE_RXCNT(events) < min(4, mspi->len)) {
+ cpu_relax();
+ events = mpc8xxx_spi_read_reg(&reg_base->event);
+ }
+
+ if (mspi->len >= 4) {
+ rx_data = mpc8xxx_spi_read_reg(&reg_base->receive);
+ } else {
+ tmp = mspi->len;
+ rx_data = 0;
+ while (tmp--) {
+ rx_data_8 = in_8((u8 *)&reg_base->receive);
+ rx_data |= (rx_data_8 << (tmp * 8));
+ }
+
+ rx_data <<= (4 - mspi->len) * 8;
+ }
+
+ mspi->len -= 4;
+
+ if (mspi->rx)
+ mspi->get_rx(rx_data, mspi);
+ }
+
+ if (!(events & SPIE_NF)) {
+ int ret;
+
+ /* spin until TX is done */
+ ret = spin_event_timeout(((events = mpc8xxx_spi_read_reg(
+ &reg_base->event)) & SPIE_NF) == 0, 1000, 0);
+ if (!ret) {
+ dev_err(mspi->dev, "tired waiting for SPIE_NF\n");
+ return;
+ }
+ }
+
+ /* 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_espi_irq(s32 irq, void *context_data)
+{
+ struct mpc8xxx_spi *mspi = context_data;
+ struct fsl_espi_reg *reg_base = mspi->reg_base;
+ irqreturn_t ret = IRQ_NONE;
+ u32 events;
+
+ /* Get interrupt events(tx/rx) */
+ events = mpc8xxx_spi_read_reg(&reg_base->event);
+ if (events)
+ ret = IRQ_HANDLED;
+
+ dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
+
+ fsl_espi_cpu_irq(mspi, events);
+
+ return ret;
+}
+
+static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
+{
+ iounmap(mspi->reg_base);
+}
+
+static struct spi_master * __devinit fsl_espi_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_espi_reg *reg_base;
+ u32 regval;
+ int i, ret = 0;
+
+ master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
+ if (!master) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ dev_set_drvdata(dev, master);
+
+ ret = mpc8xxx_spi_probe(dev, mem, irq);
+ if (ret)
+ goto err_probe;
+
+ master->setup = fsl_espi_setup;
+
+ mpc8xxx_spi = spi_master_get_devdata(master);
+ mpc8xxx_spi->spi_do_one_msg = fsl_espi_do_one_msg;
+ mpc8xxx_spi->spi_remove = fsl_espi_remove;
+
+ mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
+ if (!mpc8xxx_spi->reg_base) {
+ ret = -ENOMEM;
+ goto err_probe;
+ }
+
+ reg_base = mpc8xxx_spi->reg_base;
+
+ /* Register for SPI Interrupt */
+ ret = request_irq(mpc8xxx_spi->irq, fsl_espi_irq,
+ 0, "fsl_espi", mpc8xxx_spi);
+ if (ret)
+ goto free_irq;
+
+ if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
+ mpc8xxx_spi->rx_shift = 16;
+ mpc8xxx_spi->tx_shift = 24;
+ }
+
+ /* 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);
+
+ /* Init eSPI CS mode register */
+ for (i = 0; i < pdata->max_chipselect; i++)
+ mpc8xxx_spi_write_reg(&reg_base->csmode[i], CSMODE_INIT_VAL);
+
+ /* Enable SPI interface */
+ regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
+
+ 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)\n", reg_base, mpc8xxx_spi->irq);
+
+ return master;
+
+unreg_master:
+ free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
+free_irq:
+ iounmap(mpc8xxx_spi->reg_base);
+err_probe:
+ spi_master_put(master);
+err:
+ return ERR_PTR(ret);
+}
+
+static int of_fsl_espi_get_chipselects(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct fsl_spi_platform_data *pdata = dev->platform_data;
+ const u32 *prop;
+ int len;
+
+ prop = of_get_property(np, "fsl,espi-num-chipselects", &len);
+ if (!prop || len < sizeof(*prop)) {
+ dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
+ return -EINVAL;
+ }
+
+ pdata->max_chipselect = *prop;
+ pdata->cs_control = NULL;
+
+ return 0;
+}
+
+static int __devinit of_fsl_espi_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_espi_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_espi_probe(dev, &mem, irq.start);
+ if (IS_ERR(master)) {
+ ret = PTR_ERR(master);
+ goto err;
+ }
+
+ return 0;
+
+err:
+ return ret;
+}
+
+static int __devexit of_fsl_espi_remove(struct platform_device *dev)
+{
+ return mpc8xxx_spi_remove(&dev->dev);
+}
+
+static const struct of_device_id of_fsl_espi_match[] = {
+ { .compatible = "fsl,mpc8536-espi" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, of_fsl_espi_match);
+
+static struct platform_driver fsl_espi_driver = {
+ .driver = {
+ .name = "fsl_espi",
+ .owner = THIS_MODULE,
+ .of_match_table = of_fsl_espi_match,
+ },
+ .probe = of_fsl_espi_probe,
+ .remove = __devexit_p(of_fsl_espi_remove),
+};
+
+static int __init fsl_espi_init(void)
+{
+ return platform_driver_register(&fsl_espi_driver);
+}
+module_init(fsl_espi_init);
+
+static void __exit fsl_espi_exit(void)
+{
+ platform_driver_unregister(&fsl_espi_driver);
+}
+module_exit(fsl_espi_exit);
+
+MODULE_AUTHOR("Mingkai Hu");
+MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
+MODULE_LICENSE("GPL");