spi-fsl-espi.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>
/* 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)
#define FSL_ESPI_FIFO_SIZE 32
#define FSL_ESPI_RXTHR 15
/* Default mode/csmode for eSPI controller */
#define SPMODE_INIT_VAL (SPMODE_TXTHR(4) | SPMODE_RXTHR(FSL_ESPI_RXTHR))
#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
struct fsl_espi {
struct device *dev;
void __iomem *reg_base;
struct list_head *m_transfers;
struct spi_transfer *tx_t;
unsigned int tx_pos;
bool tx_done;
struct spi_transfer *rx_t;
unsigned int rx_pos;
bool rx_done;
bool swab;
unsigned int rxskip;
spinlock_t lock;
u32 spibrg; /* SPIBRG input clock */
struct completion done;
};
struct fsl_espi_cs {
u32 hw_mode;
};
static inline u32 fsl_espi_read_reg(struct fsl_espi *espi, int offset)
{
return ioread32be(espi->reg_base + offset);
}
static inline u16 fsl_espi_read_reg16(struct fsl_espi *espi, int offset)
{
return ioread16be(espi->reg_base + offset);
}
static inline u8 fsl_espi_read_reg8(struct fsl_espi *espi, int offset)
{
return ioread8(espi->reg_base + offset);
}
static inline void fsl_espi_write_reg(struct fsl_espi *espi, int offset,
u32 val)
{
iowrite32be(val, espi->reg_base + offset);
}
static inline void fsl_espi_write_reg16(struct fsl_espi *espi, int offset,
u16 val)
{
iowrite16be(val, espi->reg_base + offset);
}
static inline void fsl_espi_write_reg8(struct fsl_espi *espi, int offset,
u8 val)
{
iowrite8(val, espi->reg_base + offset);
}
static int fsl_espi_check_message(struct spi_message *m)
{
struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
struct spi_transfer *t, *first;
if (m->frame_length > SPCOM_TRANLEN_MAX) {
dev_err(espi->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(espi->dev, "bits_per_word/speed_hz should be the same for all transfers\n");
return -EINVAL;
}
}
/* ESPI supports MSB-first transfers for word size 8 / 16 only */
if (!(m->spi->mode & SPI_LSB_FIRST) && first->bits_per_word != 8 &&
first->bits_per_word != 16) {
dev_err(espi->dev,
"MSB-first transfer not supported for wordsize %u\n",
first->bits_per_word);
return -EINVAL;
}
return 0;
}
static unsigned int fsl_espi_check_rxskip_mode(struct spi_message *m)
{
struct spi_transfer *t;
unsigned int i = 0, rxskip = 0;
/*
* prerequisites for ESPI rxskip mode:
* - message has two transfers
* - first transfer is a write and second is a read
*
* In addition the current low-level transfer mechanism requires
* that the rxskip bytes fit into the TX FIFO. Else the transfer
* would hang because after the first FSL_ESPI_FIFO_SIZE bytes
* the TX FIFO isn't re-filled.
*/
list_for_each_entry(t, &m->transfers, transfer_list) {
if (i == 0) {
if (!t->tx_buf || t->rx_buf ||
t->len > FSL_ESPI_FIFO_SIZE)
return 0;
rxskip = t->len;
} else if (i == 1) {
if (t->tx_buf || !t->rx_buf)
return 0;
}
i++;
}
return i == 2 ? rxskip : 0;
}
static void fsl_espi_fill_tx_fifo(struct fsl_espi *espi, u32 events)
{
u32 tx_fifo_avail;
unsigned int tx_left;
const void *tx_buf;
/* if events is zero transfer has not started and tx fifo is empty */
tx_fifo_avail = events ? SPIE_TXCNT(events) : FSL_ESPI_FIFO_SIZE;
start:
tx_left = espi->tx_t->len - espi->tx_pos;
tx_buf = espi->tx_t->tx_buf;
while (tx_fifo_avail >= min(4U, tx_left) && tx_left) {
if (tx_left >= 4) {
if (!tx_buf)
fsl_espi_write_reg(espi, ESPI_SPITF, 0);
else if (espi->swab)
fsl_espi_write_reg(espi, ESPI_SPITF,
swahb32p(tx_buf + espi->tx_pos));
else
fsl_espi_write_reg(espi, ESPI_SPITF,
*(u32 *)(tx_buf + espi->tx_pos));
espi->tx_pos += 4;
tx_left -= 4;
tx_fifo_avail -= 4;
} else if (tx_left >= 2 && tx_buf && espi->swab) {
fsl_espi_write_reg16(espi, ESPI_SPITF,
swab16p(tx_buf + espi->tx_pos));
espi->tx_pos += 2;
tx_left -= 2;
tx_fifo_avail -= 2;
} else {
if (!tx_buf)
fsl_espi_write_reg8(espi, ESPI_SPITF, 0);
else
fsl_espi_write_reg8(espi, ESPI_SPITF,
*(u8 *)(tx_buf + espi->tx_pos));
espi->tx_pos += 1;
tx_left -= 1;
tx_fifo_avail -= 1;
}
}
if (!tx_left) {
/* Last transfer finished, in rxskip mode only one is needed */
if (list_is_last(&espi->tx_t->transfer_list,
espi->m_transfers) || espi->rxskip) {
espi->tx_done = true;
return;
}
espi->tx_t = list_next_entry(espi->tx_t, transfer_list);
espi->tx_pos = 0;
/* continue with next transfer if tx fifo is not full */
if (tx_fifo_avail)
goto start;
}
}
static void fsl_espi_read_rx_fifo(struct fsl_espi *espi, u32 events)
{
u32 rx_fifo_avail = SPIE_RXCNT(events);
unsigned int rx_left;
void *rx_buf;
start:
rx_left = espi->rx_t->len - espi->rx_pos;
rx_buf = espi->rx_t->rx_buf;
while (rx_fifo_avail >= min(4U, rx_left) && rx_left) {
if (rx_left >= 4) {
u32 val = fsl_espi_read_reg(espi, ESPI_SPIRF);
if (rx_buf && espi->swab)
*(u32 *)(rx_buf + espi->rx_pos) = swahb32(val);
else if (rx_buf)
*(u32 *)(rx_buf + espi->rx_pos) = val;
espi->rx_pos += 4;
rx_left -= 4;
rx_fifo_avail -= 4;
} else if (rx_left >= 2 && rx_buf && espi->swab) {
u16 val = fsl_espi_read_reg16(espi, ESPI_SPIRF);
*(u16 *)(rx_buf + espi->rx_pos) = swab16(val);
espi->rx_pos += 2;
rx_left -= 2;
rx_fifo_avail -= 2;
} else {
u8 val = fsl_espi_read_reg8(espi, ESPI_SPIRF);
if (rx_buf)
*(u8 *)(rx_buf + espi->rx_pos) = val;
espi->rx_pos += 1;
rx_left -= 1;
rx_fifo_avail -= 1;
}
}
if (!rx_left) {
if (list_is_last(&espi->rx_t->transfer_list,
espi->m_transfers)) {
espi->rx_done = true;
return;
}
espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
espi->rx_pos = 0;
/* continue with next transfer if rx fifo is not empty */
if (rx_fifo_avail)
goto start;
}
}
static void fsl_espi_setup_transfer(struct spi_device *spi,
struct spi_transfer *t)
{
struct fsl_espi *espi = spi_master_get_devdata(spi->master);
int bits_per_word = t ? t->bits_per_word : spi->bits_per_word;
u32 pm, hz = t ? t->speed_hz : spi->max_speed_hz;
struct fsl_espi_cs *cs = spi_get_ctldata(spi);
u32 hw_mode_old = cs->hw_mode;
/* 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);
pm = DIV_ROUND_UP(espi->spibrg, hz * 4) - 1;
if (pm > 15) {
cs->hw_mode |= CSMODE_DIV16;
pm = DIV_ROUND_UP(espi->spibrg, hz * 16 * 4) - 1;
}
cs->hw_mode |= CSMODE_PM(pm);
/* don't write the mode register if the mode doesn't change */
if (cs->hw_mode != hw_mode_old)
fsl_espi_write_reg(espi, ESPI_SPMODEx(spi->chip_select),
cs->hw_mode);
}
static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t)
{
struct fsl_espi *espi = spi_master_get_devdata(spi->master);
unsigned int rx_len = t->len;
u32 mask, spcom;
int ret;
reinit_completion(&espi->done);
/* Set SPCOM[CS] and SPCOM[TRANLEN] field */
spcom = SPCOM_CS(spi->chip_select);
spcom |= SPCOM_TRANLEN(t->len - 1);
/* configure RXSKIP mode */
if (espi->rxskip) {
spcom |= SPCOM_RXSKIP(espi->rxskip);
rx_len = t->len - espi->rxskip;
if (t->rx_nbits == SPI_NBITS_DUAL)
spcom |= SPCOM_DO;
}
fsl_espi_write_reg(espi, ESPI_SPCOM, spcom);
/* enable interrupts */
mask = SPIM_DON;
if (rx_len > FSL_ESPI_FIFO_SIZE)
mask |= SPIM_RXT;
fsl_espi_write_reg(espi, ESPI_SPIM, mask);
/* Prevent filling the fifo from getting interrupted */
spin_lock_irq(&espi->lock);
fsl_espi_fill_tx_fifo(espi, 0);
spin_unlock_irq(&espi->lock);
/* Won't hang up forever, SPI bus sometimes got lost interrupts... */
ret = wait_for_completion_timeout(&espi->done, 2 * HZ);
if (ret == 0)
dev_err(espi->dev, "Transfer timed out!\n");
/* disable rx ints */
fsl_espi_write_reg(espi, ESPI_SPIM, 0);
return ret == 0 ? -ETIMEDOUT : 0;
}
static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans)
{
struct fsl_espi *espi = spi_master_get_devdata(m->spi->master);
struct spi_device *spi = m->spi;
int ret;
/* In case of LSB-first and bits_per_word > 8 byte-swap all words */
espi->swab = spi->mode & SPI_LSB_FIRST && trans->bits_per_word > 8;
espi->m_transfers = &m->transfers;
espi->tx_t = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
espi->tx_pos = 0;
espi->tx_done = false;
espi->rx_t = list_first_entry(&m->transfers, struct spi_transfer,
transfer_list);
espi->rx_pos = 0;
espi->rx_done = false;
espi->rxskip = fsl_espi_check_rxskip_mode(m);
if (trans->rx_nbits == SPI_NBITS_DUAL && !espi->rxskip) {
dev_err(espi->dev, "Dual output mode requires RXSKIP mode!\n");
return -EINVAL;
}
/* In RXSKIP mode skip first transfer for reads */
if (espi->rxskip)
espi->rx_t = list_next_entry(espi->rx_t, transfer_list);
fsl_espi_setup_transfer(spi, trans);
ret = fsl_espi_bufs(spi, trans);
if (trans->delay_usecs)
udelay(trans->delay_usecs);
return ret;
}
static int fsl_espi_do_one_msg(struct spi_master *master,
struct spi_message *m)
{
unsigned int delay_usecs = 0, rx_nbits = 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;
if (t->rx_nbits > rx_nbits)
rx_nbits = t->rx_nbits;
}
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.rx_nbits = rx_nbits;
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 fsl_espi *espi;
u32 loop_mode;
struct fsl_espi_cs *cs = spi_get_ctldata(spi);
if (!cs) {
cs = kzalloc(sizeof(*cs), GFP_KERNEL);
if (!cs)
return -ENOMEM;
spi_set_ctldata(spi, cs);
}
espi = spi_master_get_devdata(spi->master);
pm_runtime_get_sync(espi->dev);
cs->hw_mode = fsl_espi_read_reg(espi, 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(espi, ESPI_SPMODE);
loop_mode &= ~SPMODE_LOOP;
if (spi->mode & SPI_LOOP)
loop_mode |= SPMODE_LOOP;
fsl_espi_write_reg(espi, ESPI_SPMODE, loop_mode);
fsl_espi_setup_transfer(spi, NULL);
pm_runtime_mark_last_busy(espi->dev);
pm_runtime_put_autosuspend(espi->dev);
return 0;
}
static void fsl_espi_cleanup(struct spi_device *spi)
{
struct fsl_espi_cs *cs = spi_get_ctldata(spi);
kfree(cs);
spi_set_ctldata(spi, NULL);
}
static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events)
{
if (!espi->rx_done)
fsl_espi_read_rx_fifo(espi, events);
if (!espi->tx_done)
fsl_espi_fill_tx_fifo(espi, events);
if (!espi->tx_done || !espi->rx_done)
return;
/* we're done, but check for errors before returning */
events = fsl_espi_read_reg(espi, ESPI_SPIE);
if (!(events & SPIE_DON))
dev_err(espi->dev,
"Transfer done but SPIE_DON isn't set!\n");
if (SPIE_RXCNT(events) || SPIE_TXCNT(events) != FSL_ESPI_FIFO_SIZE) {
dev_err(espi->dev, "Transfer done but rx/tx fifo's aren't empty!\n");
dev_err(espi->dev, "SPIE_RXCNT = %d, SPIE_TXCNT = %d\n",
SPIE_RXCNT(events), SPIE_TXCNT(events));
}
complete(&espi->done);
}
static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
{
struct fsl_espi *espi = context_data;
u32 events;
spin_lock(&espi->lock);
/* Get interrupt events(tx/rx) */
events = fsl_espi_read_reg(espi, ESPI_SPIE);
if (!events) {
spin_unlock(&espi->lock);
return IRQ_NONE;
}
dev_vdbg(espi->dev, "%s: events %x\n", __func__, events);
fsl_espi_cpu_irq(espi, events);
/* Clear the events */
fsl_espi_write_reg(espi, ESPI_SPIE, events);
spin_unlock(&espi->lock);
return IRQ_HANDLED;
}
#ifdef CONFIG_PM
static int fsl_espi_runtime_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct fsl_espi *espi = spi_master_get_devdata(master);
u32 regval;
regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
regval &= ~SPMODE_ENABLE;
fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
return 0;
}
static int fsl_espi_runtime_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
struct fsl_espi *espi = spi_master_get_devdata(master);
u32 regval;
regval = fsl_espi_read_reg(espi, ESPI_SPMODE);
regval |= SPMODE_ENABLE;
fsl_espi_write_reg(espi, ESPI_SPMODE, regval);
return 0;
}
#endif
static size_t fsl_espi_max_message_size(struct spi_device *spi)
{
return SPCOM_TRANLEN_MAX;
}
static void fsl_espi_init_regs(struct device *dev, bool initial)
{
struct spi_master *master = dev_get_drvdata(dev);
struct fsl_espi *espi = spi_master_get_devdata(master);
struct device_node *nc;
u32 csmode, cs, prop;
int ret;
/* SPI controller initializations */
fsl_espi_write_reg(espi, ESPI_SPMODE, 0);
fsl_espi_write_reg(espi, ESPI_SPIM, 0);
fsl_espi_write_reg(espi, ESPI_SPCOM, 0);
fsl_espi_write_reg(espi, ESPI_SPIE, 0xffffffff);
/* Init eSPI CS mode register */
for_each_available_child_of_node(master->dev.of_node, nc) {
/* get chip select */
ret = of_property_read_u32(nc, "reg", &cs);
if (ret || cs >= master->num_chipselect)
continue;
csmode = CSMODE_INIT_VAL;
/* check if CSBEF is set in device tree */
ret = of_property_read_u32(nc, "fsl,csbef", &prop);
if (!ret) {
csmode &= ~(CSMODE_BEF(0xf));
csmode |= CSMODE_BEF(prop);
}
/* check if CSAFT is set in device tree */
ret = of_property_read_u32(nc, "fsl,csaft", &prop);
if (!ret) {
csmode &= ~(CSMODE_AFT(0xf));
csmode |= CSMODE_AFT(prop);
}
fsl_espi_write_reg(espi, ESPI_SPMODEx(cs), csmode);
if (initial)
dev_info(dev, "cs=%u, init_csmode=0x%x\n", cs, csmode);
}
/* Enable SPI interface */
fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE);
}
static int fsl_espi_probe(struct device *dev, struct resource *mem,
unsigned int irq, unsigned int num_cs)
{
struct spi_master *master;
struct fsl_espi *espi;
int ret;
master = spi_alloc_master(dev, sizeof(struct fsl_espi));
if (!master)
return -ENOMEM;
dev_set_drvdata(dev, master);
master->mode_bits = SPI_RX_DUAL | SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
SPI_LSB_FIRST | SPI_LOOP;
master->dev.of_node = dev->of_node;
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;
master->num_chipselect = num_cs;
espi = spi_master_get_devdata(master);
spin_lock_init(&espi->lock);
espi->dev = dev;
espi->spibrg = fsl_get_sys_freq();
if (espi->spibrg == -1) {
dev_err(dev, "Can't get sys frequency!\n");
ret = -EINVAL;
goto err_probe;
}
/* determined by clock divider fields DIV16/PM in register SPMODEx */
master->min_speed_hz = DIV_ROUND_UP(espi->spibrg, 4 * 16 * 16);
master->max_speed_hz = DIV_ROUND_UP(espi->spibrg, 4);
init_completion(&espi->done);
espi->reg_base = devm_ioremap_resource(dev, mem);
if (IS_ERR(espi->reg_base)) {
ret = PTR_ERR(espi->reg_base);
goto err_probe;
}
/* Register for SPI Interrupt */
ret = devm_request_irq(dev, irq, fsl_espi_irq, 0, "fsl_espi", espi);
if (ret)
goto err_probe;
fsl_espi_init_regs(dev, true);
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 = %u)\n", espi->reg_base, 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;
u32 num_cs;
int ret;
ret = of_property_read_u32(np, "fsl,espi-num-chipselects", &num_cs);
if (ret) {
dev_err(dev, "No 'fsl,espi-num-chipselects' property\n");
return 0;
}
return num_cs;
}
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, num_cs;
int ret;
if (of_property_read_bool(np, "mode")) {
dev_err(dev, "mode property is not supported on ESPI!\n");
return -EINVAL;
}
num_cs = of_fsl_espi_get_chipselects(dev);
if (!num_cs)
return -EINVAL;
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, num_cs);
}
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;
}
return pm_runtime_force_suspend(dev);
}
static int of_fsl_espi_resume(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
int ret;
fsl_espi_init_regs(dev, false);
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");