linux/drivers/spi/spi_mpc8xxx.c

1402 lines
33 KiB
C

/*
* MPC8xxx SPI controller driver.
*
* Maintainer: Kumar Gala
*
* Copyright (C) 2006 Polycom, 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/init.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/bug.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/device.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 <linux/of_spi.h>
#include <sysdev/fsl_soc.h>
#include <asm/cpm.h>
#include <asm/qe.h>
#include <asm/irq.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 mpc8xxx_spi_reg {
u8 res1[0x20];
__be32 mode;
__be32 event;
__be32 mask;
__be32 command;
__be32 transmit;
__be32 receive;
};
/* SPI Parameter RAM */
struct spi_pram {
__be16 rbase; /* Rx Buffer descriptor base address */
__be16 tbase; /* Tx Buffer descriptor base address */
u8 rfcr; /* Rx function code */
u8 tfcr; /* Tx function code */
__be16 mrblr; /* Max receive buffer length */
__be32 rstate; /* Internal */
__be32 rdp; /* Internal */
__be16 rbptr; /* Internal */
__be16 rbc; /* Internal */
__be32 rxtmp; /* Internal */
__be32 tstate; /* Internal */
__be32 tdp; /* Internal */
__be16 tbptr; /* Internal */
__be16 tbc; /* Internal */
__be32 txtmp; /* Internal */
__be32 res; /* Tx temp. */
__be16 rpbase; /* Relocation pointer (CPM1 only) */
__be16 res1; /* Reserved */
};
/* 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)
/* SPI Controller driver's private data. */
struct mpc8xxx_spi {
struct device *dev;
struct mpc8xxx_spi_reg __iomem *base;
/* rx & tx bufs from the spi_transfer */
const void *tx;
void *rx;
int subblock;
struct spi_pram __iomem *pram;
struct cpm_buf_desc __iomem *tx_bd;
struct cpm_buf_desc __iomem *rx_bd;
struct spi_transfer *xfer_in_progress;
/* dma addresses for CPM transfers */
dma_addr_t tx_dma;
dma_addr_t rx_dma;
bool map_tx_dma;
bool map_rx_dma;
dma_addr_t dma_dummy_tx;
dma_addr_t dma_dummy_rx;
/* functions to deal with different sized buffers */
void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *);
u32(*get_tx) (struct mpc8xxx_spi *);
unsigned int count;
unsigned int irq;
unsigned nsecs; /* (clock cycle time)/2 */
u32 spibrg; /* SPIBRG input clock */
u32 rx_shift; /* RX data reg shift when in qe mode */
u32 tx_shift; /* TX data reg shift when in qe mode */
unsigned int flags;
struct workqueue_struct *workqueue;
struct work_struct work;
struct list_head queue;
spinlock_t lock;
struct completion done;
};
static void *mpc8xxx_dummy_rx;
static DEFINE_MUTEX(mpc8xxx_dummy_rx_lock);
static int mpc8xxx_dummy_rx_refcnt;
struct spi_mpc8xxx_cs {
/* functions to deal with different sized buffers */
void (*get_rx) (u32 rx_data, struct mpc8xxx_spi *);
u32 (*get_tx) (struct mpc8xxx_spi *);
u32 rx_shift; /* RX data reg shift when in qe mode */
u32 tx_shift; /* TX data reg shift when in qe mode */
u32 hw_mode; /* Holds HW mode register settings */
};
static inline void mpc8xxx_spi_write_reg(__be32 __iomem *reg, u32 val)
{
out_be32(reg, val);
}
static inline u32 mpc8xxx_spi_read_reg(__be32 __iomem *reg)
{
return in_be32(reg);
}
#define MPC83XX_SPI_RX_BUF(type) \
static \
void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
{ \
type *rx = mpc8xxx_spi->rx; \
*rx++ = (type)(data >> mpc8xxx_spi->rx_shift); \
mpc8xxx_spi->rx = rx; \
}
#define MPC83XX_SPI_TX_BUF(type) \
static \
u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi) \
{ \
u32 data; \
const type *tx = mpc8xxx_spi->tx; \
if (!tx) \
return 0; \
data = *tx++ << mpc8xxx_spi->tx_shift; \
mpc8xxx_spi->tx = tx; \
return data; \
}
MPC83XX_SPI_RX_BUF(u8)
MPC83XX_SPI_RX_BUF(u16)
MPC83XX_SPI_RX_BUF(u32)
MPC83XX_SPI_TX_BUF(u8)
MPC83XX_SPI_TX_BUF(u16)
MPC83XX_SPI_TX_BUF(u32)
static void mpc8xxx_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;
__be32 __iomem *mode = &mspi->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);
mpc8xxx_spi_write_reg(mode, cs->hw_mode);
/* 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));
}
}
}
local_irq_restore(flags);
}
static void mpc8xxx_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;
mpc8xxx_spi_change_mode(spi);
if (pdata->cs_control)
pdata->cs_control(spi, pol);
}
}
static
int mpc8xxx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
struct mpc8xxx_spi *mpc8xxx_spi;
u8 bits_per_word, pm;
u32 hz;
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;
} else {
bits_per_word = 0;
hz = 0;
}
/* 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;
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;
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 / (hz * 64);
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 / (hz * 4);
if (pm)
pm--;
cs->hw_mode |= SPMODE_PM(pm);
mpc8xxx_spi_change_mode(spi);
return 0;
}
static void mpc8xxx_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;
xfer_ofs = mspi->xfer_in_progress->len - mspi->count;
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);
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(&mspi->base->command, SPCOM_STR);
}
static int mpc8xxx_spi_cpm_bufs(struct mpc8xxx_spi *mspi,
struct spi_transfer *t, bool is_dma_mapped)
{
struct device *dev = mspi->dev;
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 {
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 {
mspi->rx_dma = t->rx_dma;
}
/* enable rx ints */
mpc8xxx_spi_write_reg(&mspi->base->mask, SPIE_RXB);
mspi->xfer_in_progress = t;
mspi->count = t->len;
/* start CPM transfers */
mpc8xxx_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 mpc8xxx_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_tx_dma)
dma_unmap_single(dev, mspi->rx_dma, t->len, DMA_FROM_DEVICE);
mspi->xfer_in_progress = NULL;
}
static int mpc8xxx_spi_cpu_bufs(struct mpc8xxx_spi *mspi,
struct spi_transfer *t, unsigned int len)
{
u32 word;
mspi->count = len;
/* enable rx ints */
mpc8xxx_spi_write_reg(&mspi->base->mask, SPIM_NE);
/* transmit word */
word = mspi->get_tx(mspi);
mpc8xxx_spi_write_reg(&mspi->base->transmit, word);
return 0;
}
static int mpc8xxx_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);
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;
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 = mpc8xxx_spi_cpm_bufs(mpc8xxx_spi, t, is_dma_mapped);
else
ret = mpc8xxx_spi_cpu_bufs(mpc8xxx_spi, t, len);
if (ret)
return ret;
wait_for_completion(&mpc8xxx_spi->done);
/* disable rx ints */
mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mask, 0);
if (mpc8xxx_spi->flags & SPI_CPM_MODE)
mpc8xxx_spi_cpm_bufs_complete(mpc8xxx_spi);
return mpc8xxx_spi->count;
}
static void mpc8xxx_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 = mpc8xxx_spi_setup_transfer(spi, t);
if (status < 0)
break;
}
if (cs_change) {
mpc8xxx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
ndelay(nsecs);
}
cs_change = t->cs_change;
if (t->len)
status = mpc8xxx_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);
mpc8xxx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
ndelay(nsecs);
}
}
m->status = status;
m->complete(m->context);
if (status || !cs_change) {
ndelay(nsecs);
mpc8xxx_spi_chipselect(spi, BITBANG_CS_INACTIVE);
}
mpc8xxx_spi_setup_transfer(spi, NULL);
}
static void mpc8xxx_spi_work(struct work_struct *work)
{
struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi,
work);
spin_lock_irq(&mpc8xxx_spi->lock);
while (!list_empty(&mpc8xxx_spi->queue)) {
struct spi_message *m = container_of(mpc8xxx_spi->queue.next,
struct spi_message, queue);
list_del_init(&m->queue);
spin_unlock_irq(&mpc8xxx_spi->lock);
mpc8xxx_spi_do_one_msg(m);
spin_lock_irq(&mpc8xxx_spi->lock);
}
spin_unlock_irq(&mpc8xxx_spi->lock);
}
static int mpc8xxx_spi_setup(struct spi_device *spi)
{
struct mpc8xxx_spi *mpc8xxx_spi;
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);
hw_mode = cs->hw_mode; /* Save orginal settings */
cs->hw_mode = mpc8xxx_spi_read_reg(&mpc8xxx_spi->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 = mpc8xxx_spi_setup_transfer(spi, NULL);
if (retval < 0) {
cs->hw_mode = hw_mode; /* Restore settings */
return retval;
}
return 0;
}
static void mpc8xxx_spi_cpm_irq(struct mpc8xxx_spi *mspi, u32 events)
{
u16 len;
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(&mspi->base->event, events);
mspi->count -= len;
if (mspi->count)
mpc8xxx_spi_cpm_bufs_start(mspi);
else
complete(&mspi->done);
}
static void mpc8xxx_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
{
/* We need handle RX first */
if (events & SPIE_NE) {
u32 rx_data = mpc8xxx_spi_read_reg(&mspi->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(&mspi->base->event)) &
SPIE_NF) == 0)
cpu_relax();
/* Clear the events */
mpc8xxx_spi_write_reg(&mspi->base->event, events);
mspi->count -= 1;
if (mspi->count) {
u32 word = mspi->get_tx(mspi);
mpc8xxx_spi_write_reg(&mspi->base->transmit, word);
} else {
complete(&mspi->done);
}
}
static irqreturn_t mpc8xxx_spi_irq(s32 irq, void *context_data)
{
struct mpc8xxx_spi *mspi = context_data;
irqreturn_t ret = IRQ_NONE;
u32 events;
/* Get interrupt events(tx/rx) */
events = mpc8xxx_spi_read_reg(&mspi->base->event);
if (events)
ret = IRQ_HANDLED;
dev_dbg(mspi->dev, "%s: events %x\n", __func__, events);
if (mspi->flags & SPI_CPM_MODE)
mpc8xxx_spi_cpm_irq(mspi, events);
else
mpc8xxx_spi_cpu_irq(mspi, events);
return ret;
}
static int mpc8xxx_spi_transfer(struct spi_device *spi,
struct spi_message *m)
{
struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
unsigned long flags;
m->actual_length = 0;
m->status = -EINPROGRESS;
spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
list_add_tail(&m->queue, &mpc8xxx_spi->queue);
queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags);
return 0;
}
static void mpc8xxx_spi_cleanup(struct spi_device *spi)
{
kfree(spi->controller_state);
}
static void *mpc8xxx_spi_alloc_dummy_rx(void)
{
mutex_lock(&mpc8xxx_dummy_rx_lock);
if (!mpc8xxx_dummy_rx)
mpc8xxx_dummy_rx = kmalloc(SPI_MRBLR, GFP_KERNEL);
if (mpc8xxx_dummy_rx)
mpc8xxx_dummy_rx_refcnt++;
mutex_unlock(&mpc8xxx_dummy_rx_lock);
return mpc8xxx_dummy_rx;
}
static void mpc8xxx_spi_free_dummy_rx(void)
{
mutex_lock(&mpc8xxx_dummy_rx_lock);
switch (mpc8xxx_dummy_rx_refcnt) {
case 0:
WARN_ON(1);
break;
case 1:
kfree(mpc8xxx_dummy_rx);
mpc8xxx_dummy_rx = NULL;
/* fall through */
default:
mpc8xxx_dummy_rx_refcnt--;
break;
}
mutex_unlock(&mpc8xxx_dummy_rx_lock);
}
static unsigned long mpc8xxx_spi_cpm_get_pram(struct mpc8xxx_spi *mspi)
{
struct device *dev = mspi->dev;
struct device_node *np = dev_archdata_get_node(&dev->archdata);
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 mpc8xxx_spi_cpm_init(struct mpc8xxx_spi *mspi)
{
struct device *dev = mspi->dev;
struct device_node *np = dev_archdata_get_node(&dev->archdata);
const u32 *iprop;
int size;
unsigned long pram_ofs;
unsigned long bds_ofs;
if (!(mspi->flags & SPI_CPM_MODE))
return 0;
if (!mpc8xxx_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 = mpc8xxx_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, mpc8xxx_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:
mpc8xxx_spi_free_dummy_rx();
return -ENOMEM;
}
static void mpc8xxx_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));
mpc8xxx_spi_free_dummy_rx();
}
static const char *mpc8xxx_spi_strmode(unsigned int flags)
{
if (flags & SPI_QE_CPU_MODE) {
return "QE CPU";
} else if (flags & SPI_CPM_MODE) {
if (flags & SPI_QE)
return "QE";
else if (flags & SPI_CPM2)
return "CPM2";
else
return "CPM1";
}
return "CPU";
}
static struct spi_master * __devinit
mpc8xxx_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;
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);
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
| SPI_LSB_FIRST | SPI_LOOP;
master->setup = mpc8xxx_spi_setup;
master->transfer = mpc8xxx_spi_transfer;
master->cleanup = mpc8xxx_spi_cleanup;
mpc8xxx_spi = spi_master_get_devdata(master);
mpc8xxx_spi->dev = dev;
mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
mpc8xxx_spi->flags = pdata->flags;
mpc8xxx_spi->spibrg = pdata->sysclk;
ret = mpc8xxx_spi_cpm_init(mpc8xxx_spi);
if (ret)
goto err_cpm_init;
mpc8xxx_spi->rx_shift = 0;
mpc8xxx_spi->tx_shift = 0;
if (mpc8xxx_spi->flags & SPI_QE_CPU_MODE) {
mpc8xxx_spi->rx_shift = 16;
mpc8xxx_spi->tx_shift = 24;
}
init_completion(&mpc8xxx_spi->done);
mpc8xxx_spi->base = ioremap(mem->start, resource_size(mem));
if (mpc8xxx_spi->base == NULL) {
ret = -ENOMEM;
goto err_ioremap;
}
mpc8xxx_spi->irq = irq;
/* Register for SPI Interrupt */
ret = request_irq(mpc8xxx_spi->irq, mpc8xxx_spi_irq,
0, "mpc8xxx_spi", mpc8xxx_spi);
if (ret != 0)
goto unmap_io;
master->bus_num = pdata->bus_num;
master->num_chipselect = pdata->max_chipselect;
/* SPI controller initializations */
mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mode, 0);
mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->mask, 0);
mpc8xxx_spi_write_reg(&mpc8xxx_spi->base->command, 0);
mpc8xxx_spi_write_reg(&mpc8xxx_spi->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(&mpc8xxx_spi->base->mode, regval);
spin_lock_init(&mpc8xxx_spi->lock);
init_completion(&mpc8xxx_spi->done);
INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work);
INIT_LIST_HEAD(&mpc8xxx_spi->queue);
mpc8xxx_spi->workqueue = create_singlethread_workqueue(
dev_name(master->dev.parent));
if (mpc8xxx_spi->workqueue == NULL) {
ret = -EBUSY;
goto free_irq;
}
ret = spi_register_master(master);
if (ret < 0)
goto unreg_master;
dev_info(dev, "at 0x%p (irq = %d), %s mode\n", mpc8xxx_spi->base,
mpc8xxx_spi->irq, mpc8xxx_spi_strmode(mpc8xxx_spi->flags));
return master;
unreg_master:
destroy_workqueue(mpc8xxx_spi->workqueue);
free_irq:
free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
unmap_io:
iounmap(mpc8xxx_spi->base);
err_ioremap:
mpc8xxx_spi_cpm_free(mpc8xxx_spi);
err_cpm_init:
spi_master_put(master);
err:
return ERR_PTR(ret);
}
static int __devexit mpc8xxx_spi_remove(struct device *dev)
{
struct mpc8xxx_spi *mpc8xxx_spi;
struct spi_master *master;
master = dev_get_drvdata(dev);
mpc8xxx_spi = spi_master_get_devdata(master);
flush_workqueue(mpc8xxx_spi->workqueue);
destroy_workqueue(mpc8xxx_spi->workqueue);
spi_unregister_master(master);
free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
iounmap(mpc8xxx_spi->base);
mpc8xxx_spi_cpm_free(mpc8xxx_spi);
return 0;
}
struct mpc8xxx_spi_probe_info {
struct fsl_spi_platform_data pdata;
int *gpios;
bool *alow_flags;
};
static struct mpc8xxx_spi_probe_info *
to_of_pinfo(struct fsl_spi_platform_data *pdata)
{
return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
}
static void mpc8xxx_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_mpc8xxx_spi_get_chipselects(struct device *dev)
{
struct device_node *np = dev_archdata_get_node(&dev->archdata);
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 = mpc8xxx_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_mpc8xxx_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_mpc8xxx_spi_probe(struct of_device *ofdev,
const struct of_device_id *ofid)
{
struct device *dev = &ofdev->dev;
struct device_node *np = ofdev->node;
struct mpc8xxx_spi_probe_info *pinfo;
struct fsl_spi_platform_data *pdata;
struct spi_master *master;
struct resource mem;
struct resource irq;
const void *prop;
int ret = -ENOMEM;
pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
if (!pinfo)
return -ENOMEM;
pdata = &pinfo->pdata;
dev->platform_data = pdata;
/* Allocate bus num dynamically. */
pdata->bus_num = -1;
/* SPI controller is either clocked from QE or SoC clock. */
pdata->sysclk = get_brgfreq();
if (pdata->sysclk == -1) {
pdata->sysclk = fsl_get_sys_freq();
if (pdata->sysclk == -1) {
ret = -ENODEV;
goto err_clk;
}
}
prop = of_get_property(np, "mode", NULL);
if (prop && !strcmp(prop, "cpu-qe"))
pdata->flags = SPI_QE_CPU_MODE;
else if (prop && !strcmp(prop, "qe"))
pdata->flags = SPI_CPM_MODE | SPI_QE;
else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
pdata->flags = SPI_CPM_MODE | SPI_CPM2;
else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
pdata->flags = SPI_CPM_MODE | SPI_CPM1;
ret = of_mpc8xxx_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 = mpc8xxx_spi_probe(dev, &mem, irq.start);
if (IS_ERR(master)) {
ret = PTR_ERR(master);
goto err;
}
of_register_spi_devices(master, np);
return 0;
err:
of_mpc8xxx_spi_free_chipselects(dev);
err_clk:
kfree(pinfo);
return ret;
}
static int __devexit of_mpc8xxx_spi_remove(struct of_device *ofdev)
{
int ret;
ret = mpc8xxx_spi_remove(&ofdev->dev);
if (ret)
return ret;
of_mpc8xxx_spi_free_chipselects(&ofdev->dev);
return 0;
}
static const struct of_device_id of_mpc8xxx_spi_match[] = {
{ .compatible = "fsl,spi" },
{},
};
MODULE_DEVICE_TABLE(of, of_mpc8xxx_spi_match);
static struct of_platform_driver of_mpc8xxx_spi_driver = {
.name = "mpc8xxx_spi",
.match_table = of_mpc8xxx_spi_match,
.probe = of_mpc8xxx_spi_probe,
.remove = __devexit_p(of_mpc8xxx_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;
unsigned 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)
return -EINVAL;
master = mpc8xxx_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 mpc8xxx_spi_init(void)
{
legacy_driver_register();
return of_register_platform_driver(&of_mpc8xxx_spi_driver);
}
static void __exit mpc8xxx_spi_exit(void)
{
of_unregister_platform_driver(&of_mpc8xxx_spi_driver);
legacy_driver_unregister();
}
module_init(mpc8xxx_spi_init);
module_exit(mpc8xxx_spi_exit);
MODULE_AUTHOR("Kumar Gala");
MODULE_DESCRIPTION("Simple MPC8xxx SPI Driver");
MODULE_LICENSE("GPL");