linux/drivers/spi/spi-fsl-espi.c

791 lines
20 KiB
C

/*
* 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/delay.h>
#include <linux/err.h>
#include <linux/fsl_devices.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
#include <sysdev/fsl_soc.h>
#include "spi-fsl-lib.h"
/* eSPI Controller registers */
#define ESPI_SPMODE 0x00 /* eSPI mode register */
#define ESPI_SPIE 0x04 /* eSPI event register */
#define ESPI_SPIM 0x08 /* eSPI mask register */
#define ESPI_SPCOM 0x0c /* eSPI command register */
#define ESPI_SPITF 0x10 /* eSPI transmit FIFO access register*/
#define ESPI_SPIRF 0x14 /* eSPI receive FIFO access register*/
#define ESPI_SPMODE0 0x20 /* eSPI cs0 mode register */
#define ESPI_SPMODEx(x) (ESPI_SPMODE0 + (x) * 4)
/* eSPI Controller mode register definitions */
#define SPMODE_ENABLE BIT(31)
#define SPMODE_LOOP BIT(30)
#define SPMODE_TXTHR(x) ((x) << 8)
#define SPMODE_RXTHR(x) ((x) << 0)
/* eSPI Controller CS mode register definitions */
#define CSMODE_CI_INACTIVEHIGH BIT(31)
#define CSMODE_CP_BEGIN_EDGECLK BIT(30)
#define CSMODE_REV BIT(29)
#define CSMODE_DIV16 BIT(28)
#define CSMODE_PM(x) ((x) << 24)
#define CSMODE_POL_1 BIT(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_RXCNT(reg) ((reg >> 24) & 0x3F)
#define SPIE_TXCNT(reg) ((reg >> 16) & 0x3F)
#define SPIE_TXE BIT(15) /* TX FIFO empty */
#define SPIE_DON BIT(14) /* TX done */
#define SPIE_RXT BIT(13) /* RX FIFO threshold */
#define SPIE_RXF BIT(12) /* RX FIFO full */
#define SPIE_TXT BIT(11) /* TX FIFO threshold*/
#define SPIE_RNE BIT(9) /* RX FIFO not empty */
#define SPIE_TNF BIT(8) /* TX FIFO not full */
/* SPIM register values */
#define SPIM_TXE BIT(15) /* TX FIFO empty */
#define SPIM_DON BIT(14) /* TX done */
#define SPIM_RXT BIT(13) /* RX FIFO threshold */
#define SPIM_RXF BIT(12) /* RX FIFO full */
#define SPIM_TXT BIT(11) /* TX FIFO threshold*/
#define SPIM_RNE BIT(9) /* RX FIFO not empty */
#define SPIM_TNF BIT(8) /* TX FIFO not full */
/* SPCOM register values */
#define SPCOM_CS(x) ((x) << 30)
#define SPCOM_DO BIT(28) /* Dual output */
#define SPCOM_TO BIT(27) /* TX only */
#define SPCOM_RXSKIP(x) ((x) << 16)
#define SPCOM_TRANLEN(x) ((x) << 0)
#define SPCOM_TRANLEN_MAX 0x10000 /* Max transaction length */
#define AUTOSUSPEND_TIMEOUT 2000
static inline u32 fsl_espi_read_reg(struct mpc8xxx_spi *mspi, int offset)
{
return ioread32be(mspi->reg_base + offset);
}
static inline u8 fsl_espi_read_reg8(struct mpc8xxx_spi *mspi, int offset)
{
return ioread8(mspi->reg_base + offset);
}
static inline void fsl_espi_write_reg(struct mpc8xxx_spi *mspi, int offset,
u32 val)
{
iowrite32be(val, mspi->reg_base + offset);
}
static inline void fsl_espi_write_reg8(struct mpc8xxx_spi *mspi, int offset,
u8 val)
{
iowrite8(val, mspi->reg_base + offset);
}
static void fsl_espi_copy_to_buf(struct spi_message *m,
struct mpc8xxx_spi *mspi)
{
struct spi_transfer *t;
u8 *buf = mspi->local_buf;
list_for_each_entry(t, &m->transfers, transfer_list) {
if (t->tx_buf)
memcpy(buf, t->tx_buf, t->len);
else
memset(buf, 0, t->len);
buf += t->len;
}
}
static void fsl_espi_copy_from_buf(struct spi_message *m,
struct mpc8xxx_spi *mspi)
{
struct spi_transfer *t;
u8 *buf = mspi->local_buf;
list_for_each_entry(t, &m->transfers, transfer_list) {
if (t->rx_buf)
memcpy(t->rx_buf, buf, t->len);
buf += t->len;
}
}
static int fsl_espi_check_message(struct spi_message *m)
{
struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
struct spi_transfer *t, *first;
if (m->frame_length > SPCOM_TRANLEN_MAX) {
dev_err(mspi->dev, "message too long, size is %u bytes\n",
m->frame_length);
return -EMSGSIZE;
}
first = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
list_for_each_entry(t, &m->transfers, transfer_list) {
if (first->bits_per_word != t->bits_per_word ||
first->speed_hz != t->speed_hz) {
dev_err(mspi->dev, "bits_per_word/speed_hz should be the same for all transfers\n");
return -EINVAL;
}
}
return 0;
}
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;
u32 tmp;
unsigned long flags;
/* Turn off IRQs locally to minimize time that SPI is disabled. */
local_irq_save(flags);
/* Turn off SPI unit prior changing mode */
tmp = fsl_espi_read_reg(mspi, ESPI_SPMODE);
fsl_espi_write_reg(mspi, ESPI_SPMODE, tmp & ~SPMODE_ENABLE);
fsl_espi_write_reg(mspi, ESPI_SPMODEx(spi->chip_select),
cs->hw_mode);
fsl_espi_write_reg(mspi, ESPI_SPMODE, tmp);
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 void 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 = t ? t->bits_per_word : spi->bits_per_word;
u32 hz = t ? t->speed_hz : spi->max_speed_hz;
u8 pm;
struct spi_mpc8xxx_cs *cs = spi->controller_state;
cs->rx_shift = 0;
cs->tx_shift = 0;
cs->get_rx = mpc8xxx_spi_rx_buf_u32;
cs->get_tx = mpc8xxx_spi_tx_buf_u32;
if (bits_per_word <= 8) {
cs->rx_shift = 8 - bits_per_word;
} else {
cs->rx_shift = 16 - bits_per_word;
if (spi->mode & SPI_LSB_FIRST)
cs->get_tx = fsl_espi_tx_buf_lsb;
}
mpc8xxx_spi->rx_shift = cs->rx_shift;
mpc8xxx_spi->tx_shift = cs->tx_shift;
mpc8xxx_spi->get_rx = cs->get_rx;
mpc8xxx_spi->get_tx = cs->get_tx;
/* mask out bits we are going to set */
cs->hw_mode &= ~(CSMODE_LEN(0xF) | CSMODE_DIV16 | CSMODE_PM(0xF));
cs->hw_mode |= CSMODE_LEN(bits_per_word - 1);
if ((mpc8xxx_spi->spibrg / hz) > 64) {
cs->hw_mode |= CSMODE_DIV16;
pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
WARN_ONCE(pm > 33, "%s: Requested speed is too low: %d Hz. "
"Will use %d Hz instead.\n", dev_name(&spi->dev),
hz, mpc8xxx_spi->spibrg / (4 * 16 * (32 + 1)));
if (pm > 33)
pm = 33;
} else {
pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
}
if (pm)
pm--;
if (pm < 2)
pm = 2;
cs->hw_mode |= CSMODE_PM(pm);
fsl_espi_change_mode(spi);
}
static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
{
struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
u32 word;
int ret;
mpc8xxx_spi->len = t->len;
mpc8xxx_spi->count = roundup(t->len, 4) / 4;
mpc8xxx_spi->tx = t->tx_buf;
mpc8xxx_spi->rx = t->rx_buf;
reinit_completion(&mpc8xxx_spi->done);
/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM,
(SPCOM_CS(spi->chip_select) | SPCOM_TRANLEN(t->len - 1)));
/* enable rx ints */
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, SPIM_RNE);
/* transmit word */
word = mpc8xxx_spi->get_tx(mpc8xxx_spi);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPITF, word);
/* Won't hang up forever, SPI bus sometimes got lost interrupts... */
ret = wait_for_completion_timeout(&mpc8xxx_spi->done, 2 * HZ);
if (ret == 0)
dev_err(mpc8xxx_spi->dev,
"Transaction hanging up (left %d bytes)\n",
mpc8xxx_spi->count);
/* disable rx ints */
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
return mpc8xxx_spi->count > 0 ? -EMSGSIZE : 0;
}
static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans)
{
struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
struct spi_device *spi = m->spi;
int ret;
fsl_espi_copy_to_buf(m, mspi);
fsl_espi_setup_transfer(spi, trans);
ret = fsl_espi_bufs(spi, trans);
if (trans->delay_usecs)
udelay(trans->delay_usecs);
fsl_espi_setup_transfer(spi, NULL);
if (!ret)
fsl_espi_copy_from_buf(m, mspi);
return ret;
}
static int fsl_espi_do_one_msg(struct spi_master *master,
struct spi_message *m)
{
struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
unsigned int delay_usecs = 0;
struct spi_transfer *t, trans = {};
int ret;
ret = fsl_espi_check_message(m);
if (ret)
goto out;
list_for_each_entry(t, &m->transfers, transfer_list) {
if (t->delay_usecs > delay_usecs)
delay_usecs = t->delay_usecs;
}
t = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
trans.len = m->frame_length;
trans.speed_hz = t->speed_hz;
trans.bits_per_word = t->bits_per_word;
trans.delay_usecs = delay_usecs;
trans.tx_buf = mspi->local_buf;
trans.rx_buf = mspi->local_buf;
if (trans.len)
ret = fsl_espi_trans(m, &trans);
m->actual_length = ret ? 0 : trans.len;
out:
if (m->status == -EINPROGRESS)
m->status = ret;
spi_finalize_current_message(master);
return ret;
}
static int fsl_espi_setup(struct spi_device *spi)
{
struct mpc8xxx_spi *mpc8xxx_spi;
u32 loop_mode;
struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
if (!spi->max_speed_hz)
return -EINVAL;
if (!cs) {
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs)
return -ENOMEM;
spi_set_ctldata(spi, cs);
}
mpc8xxx_spi = spi_master_get_devdata(spi->master);
pm_runtime_get_sync(mpc8xxx_spi->dev);
cs->hw_mode = fsl_espi_read_reg(mpc8xxx_spi,
ESPI_SPMODEx(spi->chip_select));
/* mask out bits we are going to set */
cs->hw_mode &= ~(CSMODE_CP_BEGIN_EDGECLK | CSMODE_CI_INACTIVEHIGH
| CSMODE_REV);
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 = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
loop_mode &= ~SPMODE_LOOP;
if (spi->mode & SPI_LOOP)
loop_mode |= SPMODE_LOOP;
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, loop_mode);
fsl_espi_setup_transfer(spi, NULL);
pm_runtime_mark_last_busy(mpc8xxx_spi->dev);
pm_runtime_put_autosuspend(mpc8xxx_spi->dev);
return 0;
}
static void fsl_espi_cleanup(struct spi_device *spi)
{
struct spi_mpc8xxx_cs *cs = spi_get_ctldata(spi);
kfree(cs);
spi_set_ctldata(spi, NULL);
}
static void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
{
/* We need handle RX first */
if (events & SPIE_RNE) {
u32 rx_data, tmp;
u8 rx_data_8;
int rx_nr_bytes = 4;
int ret;
/* Spin until RX is done */
if (SPIE_RXCNT(events) < min(4, mspi->len)) {
ret = spin_event_timeout(
!(SPIE_RXCNT(events =
fsl_espi_read_reg(mspi, ESPI_SPIE)) <
min(4, mspi->len)),
10000, 0); /* 10 msec */
if (!ret)
dev_err(mspi->dev,
"tired waiting for SPIE_RXCNT\n");
}
if (mspi->len >= 4) {
rx_data = fsl_espi_read_reg(mspi, ESPI_SPIRF);
} else if (mspi->len <= 0) {
dev_err(mspi->dev,
"unexpected RX(SPIE_RNE) interrupt occurred,\n"
"(local rxlen %d bytes, reg rxlen %d bytes)\n",
min(4, mspi->len), SPIE_RXCNT(events));
rx_nr_bytes = 0;
} else {
rx_nr_bytes = mspi->len;
tmp = mspi->len;
rx_data = 0;
while (tmp--) {
rx_data_8 = fsl_espi_read_reg8(mspi,
ESPI_SPIRF);
rx_data |= (rx_data_8 << (tmp * 8));
}
rx_data <<= (4 - mspi->len) * 8;
}
mspi->len -= rx_nr_bytes;
if (rx_nr_bytes && mspi->rx)
mspi->get_rx(rx_data, mspi);
}
if (!(events & SPIE_TNF)) {
int ret;
/* spin until TX is done */
ret = spin_event_timeout(((events = fsl_espi_read_reg(
mspi, ESPI_SPIE)) & SPIE_TNF), 1000, 0);
if (!ret) {
dev_err(mspi->dev, "tired waiting for SPIE_TNF\n");
complete(&mspi->done);
return;
}
}
mspi->count -= 1;
if (mspi->count) {
u32 word = mspi->get_tx(mspi);
fsl_espi_write_reg(mspi, ESPI_SPITF, word);
} else {
complete(&mspi->done);
}
}
static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
{
struct mpc8xxx_spi *mspi = context_data;
u32 events;
/* Get interrupt events(tx/rx) */
events = fsl_espi_read_reg(mspi, ESPI_SPIE);
if (!events)
return IRQ_NONE;
dev_vdbg(mspi->dev, "%s: events %x\n", __func__, events);
fsl_espi_cpu_irq(mspi, events);
/* Clear the events */
fsl_espi_write_reg(mspi, ESPI_SPIE, events);
return IRQ_HANDLED;
}
#ifdef CONFIG_PM
static int fsl_espi_runtime_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
u32 regval;
regval = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
regval &= ~SPMODE_ENABLE;
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
return 0;
}
static int fsl_espi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(master);
u32 regval;
regval = fsl_espi_read_reg(mpc8xxx_spi, ESPI_SPMODE);
regval |= SPMODE_ENABLE;
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
return 0;
}
#endif
static size_t fsl_espi_max_message_size(struct spi_device *spi)
{
return SPCOM_TRANLEN_MAX;
}
static int fsl_espi_probe(struct device *dev, struct resource *mem,
unsigned int irq)
{
struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
struct spi_master *master;
struct mpc8xxx_spi *mpc8xxx_spi;
struct device_node *nc;
const __be32 *prop;
u32 regval, csmode;
int i, len, ret;
master = spi_alloc_master(dev, sizeof(struct mpc8xxx_spi));
if (!master)
return -ENOMEM;
dev_set_drvdata(dev, master);
mpc8xxx_spi_probe(dev, mem, irq);
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
master->setup = fsl_espi_setup;
master->cleanup = fsl_espi_cleanup;
master->transfer_one_message = fsl_espi_do_one_msg;
master->auto_runtime_pm = true;
master->max_message_size = fsl_espi_max_message_size;
mpc8xxx_spi = spi_master_get_devdata(master);
mpc8xxx_spi->local_buf =
devm_kmalloc(dev, SPCOM_TRANLEN_MAX, GFP_KERNEL);
if (!mpc8xxx_spi->local_buf) {
ret = -ENOMEM;
goto err_probe;
}
mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
if (IS_ERR(mpc8xxx_spi->reg_base)) {
ret = PTR_ERR(mpc8xxx_spi->reg_base);
goto err_probe;
}
/* Register for SPI Interrupt */
ret = devm_request_irq(dev, mpc8xxx_spi->irq, fsl_espi_irq,
0, "fsl_espi", mpc8xxx_spi);
if (ret)
goto err_probe;
if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
mpc8xxx_spi->rx_shift = 16;
mpc8xxx_spi->tx_shift = 24;
}
/* SPI controller initializations */
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIE, 0xffffffff);
/* Init eSPI CS mode register */
for_each_available_child_of_node(master->dev.of_node, nc) {
/* get chip select */
prop = of_get_property(nc, "reg", &len);
if (!prop || len < sizeof(*prop))
continue;
i = be32_to_cpup(prop);
if (i < 0 || i >= pdata->max_chipselect)
continue;
csmode = CSMODE_INIT_VAL;
/* check if CSBEF is set in device tree */
prop = of_get_property(nc, "fsl,csbef", &len);
if (prop && len >= sizeof(*prop)) {
csmode &= ~(CSMODE_BEF(0xf));
csmode |= CSMODE_BEF(be32_to_cpup(prop));
}
/* check if CSAFT is set in device tree */
prop = of_get_property(nc, "fsl,csaft", &len);
if (prop && len >= sizeof(*prop)) {
csmode &= ~(CSMODE_AFT(0xf));
csmode |= CSMODE_AFT(be32_to_cpup(prop));
}
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODEx(i), csmode);
dev_info(dev, "cs=%d, init_csmode=0x%x\n", i, csmode);
}
/* Enable SPI interface */
regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
pm_runtime_set_autosuspend_delay(dev, AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
ret = devm_spi_register_master(dev, master);
if (ret < 0)
goto err_pm;
dev_info(dev, "at 0x%p (irq = %d)\n", mpc8xxx_spi->reg_base,
mpc8xxx_spi->irq);
pm_runtime_mark_last_busy(dev);
pm_runtime_put_autosuspend(dev);
return 0;
err_pm:
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
pm_runtime_set_suspended(dev);
err_probe:
spi_master_put(master);
return 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_get_platdata(dev);
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 of_fsl_espi_probe(struct platform_device *ofdev)
{
struct device *dev = &ofdev->dev;
struct device_node *np = ofdev->dev.of_node;
struct resource mem;
unsigned int irq;
int ret;
ret = of_mpc8xxx_spi_probe(ofdev);
if (ret)
return ret;
ret = of_fsl_espi_get_chipselects(dev);
if (ret)
return ret;
ret = of_address_to_resource(np, 0, &mem);
if (ret)
return ret;
irq = irq_of_parse_and_map(np, 0);
if (!irq)
return -EINVAL;
return fsl_espi_probe(dev, &mem, irq);
}
static int of_fsl_espi_remove(struct platform_device *dev)
{
pm_runtime_disable(&dev->dev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int of_fsl_espi_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
int ret;
ret = spi_master_suspend(master);
if (ret) {
dev_warn(dev, "cannot suspend master\n");
return ret;
}
ret = pm_runtime_force_suspend(dev);
if (ret < 0)
return ret;
return 0;
}
static int of_fsl_espi_resume(struct device *dev)
{
struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
struct spi_master *master = dev_get_drvdata(dev);
struct mpc8xxx_spi *mpc8xxx_spi;
u32 regval;
int i, ret;
mpc8xxx_spi = spi_master_get_devdata(master);
/* SPI controller initializations */
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIM, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPCOM, 0);
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPIE, 0xffffffff);
/* Init eSPI CS mode register */
for (i = 0; i < pdata->max_chipselect; i++)
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODEx(i),
CSMODE_INIT_VAL);
/* Enable SPI interface */
regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE;
fsl_espi_write_reg(mpc8xxx_spi, ESPI_SPMODE, regval);
ret = pm_runtime_force_resume(dev);
if (ret < 0)
return ret;
return spi_master_resume(master);
}
#endif /* CONFIG_PM_SLEEP */
static const struct dev_pm_ops espi_pm = {
SET_RUNTIME_PM_OPS(fsl_espi_runtime_suspend,
fsl_espi_runtime_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(of_fsl_espi_suspend, of_fsl_espi_resume)
};
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",
.of_match_table = of_fsl_espi_match,
.pm = &espi_pm,
},
.probe = of_fsl_espi_probe,
.remove = of_fsl_espi_remove,
};
module_platform_driver(fsl_espi_driver);
MODULE_AUTHOR("Mingkai Hu");
MODULE_DESCRIPTION("Enhanced Freescale SPI Driver");
MODULE_LICENSE("GPL");