spi: controller driver for Designware SPI core

Driver for the Designware SPI core, it supports multipul interfaces like
PCI/APB etc.  User can use "dw_apb_ssi_db.pdf" from Synopsys as HW
datasheet.

[randy.dunlap@oracle.com: fix build]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Feng Tang 2009-12-14 14:20:22 -08:00 committed by Grant Likely
parent db389b6143
commit e24c745272
5 changed files with 1337 additions and 0 deletions

View file

@ -292,6 +292,16 @@ config SPI_NUC900
# Add new SPI master controllers in alphabetical order above this line
#
config SPI_DESIGNWARE
bool "DesignWare SPI controller core support"
depends on SPI_MASTER
help
general driver for SPI controller core from DesignWare
config SPI_DW_PCI
tristate "PCI interface driver for DW SPI core"
depends on SPI_DESIGNWARE && PCI
#
# There are lots of SPI device types, with sensors and memory
# being probably the most widely used ones.

View file

@ -16,6 +16,8 @@ obj-$(CONFIG_SPI_BFIN) += spi_bfin5xx.o
obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o
obj-$(CONFIG_SPI_AU1550) += au1550_spi.o
obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o
obj-$(CONFIG_SPI_DESIGNWARE) += dw_spi.o
obj-$(CONFIG_SPI_DW_PCI) += dw_spi_pci.o
obj-$(CONFIG_SPI_GPIO) += spi_gpio.o
obj-$(CONFIG_SPI_IMX) += spi_imx.o
obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o

944
drivers/spi/dw_spi.c Normal file
View file

@ -0,0 +1,944 @@
/*
* dw_spi.c - Designware SPI core controller driver (refer pxa2xx_spi.c)
*
* Copyright (c) 2009, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/highmem.h>
#include <linux/delay.h>
#include <linux/spi/dw_spi.h>
#include <linux/spi/spi.h>
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#endif
#define START_STATE ((void *)0)
#define RUNNING_STATE ((void *)1)
#define DONE_STATE ((void *)2)
#define ERROR_STATE ((void *)-1)
#define QUEUE_RUNNING 0
#define QUEUE_STOPPED 1
#define MRST_SPI_DEASSERT 0
#define MRST_SPI_ASSERT 1
/* Slave spi_dev related */
struct chip_data {
u16 cr0;
u8 cs; /* chip select pin */
u8 n_bytes; /* current is a 1/2/4 byte op */
u8 tmode; /* TR/TO/RO/EEPROM */
u8 type; /* SPI/SSP/MicroWire */
u8 poll_mode; /* 1 means use poll mode */
u32 dma_width;
u32 rx_threshold;
u32 tx_threshold;
u8 enable_dma;
u8 bits_per_word;
u16 clk_div; /* baud rate divider */
u32 speed_hz; /* baud rate */
int (*write)(struct dw_spi *dws);
int (*read)(struct dw_spi *dws);
void (*cs_control)(u32 command);
};
#ifdef CONFIG_DEBUG_FS
static int spi_show_regs_open(struct inode *inode, struct file *file)
{
file->private_data = inode->i_private;
return 0;
}
#define SPI_REGS_BUFSIZE 1024
static ssize_t spi_show_regs(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct dw_spi *dws;
char *buf;
u32 len = 0;
ssize_t ret;
dws = file->private_data;
buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL);
if (!buf)
return 0;
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"MRST SPI0 registers:\n");
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"=================================\n");
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"CTRL0: \t\t0x%08x\n", dw_readl(dws, ctrl0));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"CTRL1: \t\t0x%08x\n", dw_readl(dws, ctrl1));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"SSIENR: \t0x%08x\n", dw_readl(dws, ssienr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"SER: \t\t0x%08x\n", dw_readl(dws, ser));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"BAUDR: \t\t0x%08x\n", dw_readl(dws, baudr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"TXFTLR: \t0x%08x\n", dw_readl(dws, txfltr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"RXFTLR: \t0x%08x\n", dw_readl(dws, rxfltr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"TXFLR: \t\t0x%08x\n", dw_readl(dws, txflr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"RXFLR: \t\t0x%08x\n", dw_readl(dws, rxflr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"SR: \t\t0x%08x\n", dw_readl(dws, sr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"IMR: \t\t0x%08x\n", dw_readl(dws, imr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"ISR: \t\t0x%08x\n", dw_readl(dws, isr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"DMACR: \t\t0x%08x\n", dw_readl(dws, dmacr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"DMATDLR: \t0x%08x\n", dw_readl(dws, dmatdlr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"DMARDLR: \t0x%08x\n", dw_readl(dws, dmardlr));
len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
"=================================\n");
ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
kfree(buf);
return ret;
}
static const struct file_operations mrst_spi_regs_ops = {
.owner = THIS_MODULE,
.open = spi_show_regs_open,
.read = spi_show_regs,
};
static int mrst_spi_debugfs_init(struct dw_spi *dws)
{
dws->debugfs = debugfs_create_dir("mrst_spi", NULL);
if (!dws->debugfs)
return -ENOMEM;
debugfs_create_file("registers", S_IFREG | S_IRUGO,
dws->debugfs, (void *)dws, &mrst_spi_regs_ops);
return 0;
}
static void mrst_spi_debugfs_remove(struct dw_spi *dws)
{
if (dws->debugfs)
debugfs_remove_recursive(dws->debugfs);
}
#else
static inline int mrst_spi_debugfs_init(struct dw_spi *dws)
{
}
static inline void mrst_spi_debugfs_remove(struct dw_spi *dws)
{
}
#endif /* CONFIG_DEBUG_FS */
static void wait_till_not_busy(struct dw_spi *dws)
{
unsigned long end = jiffies + usecs_to_jiffies(1000);
while (time_before(jiffies, end)) {
if (!(dw_readw(dws, sr) & SR_BUSY))
return;
}
dev_err(&dws->master->dev,
"DW SPI: Stutus keeps busy for 1000us after a read/write!\n");
}
static void flush(struct dw_spi *dws)
{
while (dw_readw(dws, sr) & SR_RF_NOT_EMPT)
dw_readw(dws, dr);
wait_till_not_busy(dws);
}
static void null_cs_control(u32 command)
{
}
static int null_writer(struct dw_spi *dws)
{
u8 n_bytes = dws->n_bytes;
if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
|| (dws->tx == dws->tx_end))
return 0;
dw_writew(dws, dr, 0);
dws->tx += n_bytes;
wait_till_not_busy(dws);
return 1;
}
static int null_reader(struct dw_spi *dws)
{
u8 n_bytes = dws->n_bytes;
while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
&& (dws->rx < dws->rx_end)) {
dw_readw(dws, dr);
dws->rx += n_bytes;
}
wait_till_not_busy(dws);
return dws->rx == dws->rx_end;
}
static int u8_writer(struct dw_spi *dws)
{
if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
|| (dws->tx == dws->tx_end))
return 0;
dw_writew(dws, dr, *(u8 *)(dws->tx));
++dws->tx;
wait_till_not_busy(dws);
return 1;
}
static int u8_reader(struct dw_spi *dws)
{
while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
&& (dws->rx < dws->rx_end)) {
*(u8 *)(dws->rx) = dw_readw(dws, dr);
++dws->rx;
}
wait_till_not_busy(dws);
return dws->rx == dws->rx_end;
}
static int u16_writer(struct dw_spi *dws)
{
if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
|| (dws->tx == dws->tx_end))
return 0;
dw_writew(dws, dr, *(u16 *)(dws->tx));
dws->tx += 2;
wait_till_not_busy(dws);
return 1;
}
static int u16_reader(struct dw_spi *dws)
{
u16 temp;
while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
&& (dws->rx < dws->rx_end)) {
temp = dw_readw(dws, dr);
*(u16 *)(dws->rx) = temp;
dws->rx += 2;
}
wait_till_not_busy(dws);
return dws->rx == dws->rx_end;
}
static void *next_transfer(struct dw_spi *dws)
{
struct spi_message *msg = dws->cur_msg;
struct spi_transfer *trans = dws->cur_transfer;
/* Move to next transfer */
if (trans->transfer_list.next != &msg->transfers) {
dws->cur_transfer =
list_entry(trans->transfer_list.next,
struct spi_transfer,
transfer_list);
return RUNNING_STATE;
} else
return DONE_STATE;
}
/*
* Note: first step is the protocol driver prepares
* a dma-capable memory, and this func just need translate
* the virt addr to physical
*/
static int map_dma_buffers(struct dw_spi *dws)
{
if (!dws->cur_msg->is_dma_mapped || !dws->dma_inited
|| !dws->cur_chip->enable_dma)
return 0;
if (dws->cur_transfer->tx_dma)
dws->tx_dma = dws->cur_transfer->tx_dma;
if (dws->cur_transfer->rx_dma)
dws->rx_dma = dws->cur_transfer->rx_dma;
return 1;
}
/* Caller already set message->status; dma and pio irqs are blocked */
static void giveback(struct dw_spi *dws)
{
struct spi_transfer *last_transfer;
unsigned long flags;
struct spi_message *msg;
spin_lock_irqsave(&dws->lock, flags);
msg = dws->cur_msg;
dws->cur_msg = NULL;
dws->cur_transfer = NULL;
dws->prev_chip = dws->cur_chip;
dws->cur_chip = NULL;
dws->dma_mapped = 0;
queue_work(dws->workqueue, &dws->pump_messages);
spin_unlock_irqrestore(&dws->lock, flags);
last_transfer = list_entry(msg->transfers.prev,
struct spi_transfer,
transfer_list);
if (!last_transfer->cs_change)
dws->cs_control(MRST_SPI_DEASSERT);
msg->state = NULL;
if (msg->complete)
msg->complete(msg->context);
}
static void int_error_stop(struct dw_spi *dws, const char *msg)
{
/* Stop and reset hw */
flush(dws);
spi_enable_chip(dws, 0);
dev_err(&dws->master->dev, "%s\n", msg);
dws->cur_msg->state = ERROR_STATE;
tasklet_schedule(&dws->pump_transfers);
}
static void transfer_complete(struct dw_spi *dws)
{
/* Update total byte transfered return count actual bytes read */
dws->cur_msg->actual_length += dws->len;
/* Move to next transfer */
dws->cur_msg->state = next_transfer(dws);
/* Handle end of message */
if (dws->cur_msg->state == DONE_STATE) {
dws->cur_msg->status = 0;
giveback(dws);
} else
tasklet_schedule(&dws->pump_transfers);
}
static irqreturn_t interrupt_transfer(struct dw_spi *dws)
{
u16 irq_status, irq_mask = 0x3f;
irq_status = dw_readw(dws, isr) & irq_mask;
/* Error handling */
if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
dw_readw(dws, txoicr);
dw_readw(dws, rxoicr);
dw_readw(dws, rxuicr);
int_error_stop(dws, "interrupt_transfer: fifo overrun");
return IRQ_HANDLED;
}
/* INT comes from tx */
if (dws->tx && (irq_status & SPI_INT_TXEI)) {
while (dws->tx < dws->tx_end)
dws->write(dws);
if (dws->tx == dws->tx_end) {
spi_mask_intr(dws, SPI_INT_TXEI);
transfer_complete(dws);
}
}
/* INT comes from rx */
if (dws->rx && (irq_status & SPI_INT_RXFI)) {
if (dws->read(dws))
transfer_complete(dws);
}
return IRQ_HANDLED;
}
static irqreturn_t dw_spi_irq(int irq, void *dev_id)
{
struct dw_spi *dws = dev_id;
if (!dws->cur_msg) {
spi_mask_intr(dws, SPI_INT_TXEI);
/* Never fail */
return IRQ_HANDLED;
}
return dws->transfer_handler(dws);
}
/* Must be called inside pump_transfers() */
static void poll_transfer(struct dw_spi *dws)
{
if (dws->tx) {
while (dws->write(dws))
dws->read(dws);
}
dws->read(dws);
transfer_complete(dws);
}
static void dma_transfer(struct dw_spi *dws, int cs_change)
{
}
static void pump_transfers(unsigned long data)
{
struct dw_spi *dws = (struct dw_spi *)data;
struct spi_message *message = NULL;
struct spi_transfer *transfer = NULL;
struct spi_transfer *previous = NULL;
struct spi_device *spi = NULL;
struct chip_data *chip = NULL;
u8 bits = 0;
u8 imask = 0;
u8 cs_change = 0;
u16 clk_div = 0;
u32 speed = 0;
u32 cr0 = 0;
/* Get current state information */
message = dws->cur_msg;
transfer = dws->cur_transfer;
chip = dws->cur_chip;
spi = message->spi;
if (message->state == ERROR_STATE) {
message->status = -EIO;
goto early_exit;
}
/* Handle end of message */
if (message->state == DONE_STATE) {
message->status = 0;
goto early_exit;
}
/* Delay if requested at end of transfer*/
if (message->state == RUNNING_STATE) {
previous = list_entry(transfer->transfer_list.prev,
struct spi_transfer,
transfer_list);
if (previous->delay_usecs)
udelay(previous->delay_usecs);
}
dws->n_bytes = chip->n_bytes;
dws->dma_width = chip->dma_width;
dws->cs_control = chip->cs_control;
dws->rx_dma = transfer->rx_dma;
dws->tx_dma = transfer->tx_dma;
dws->tx = (void *)transfer->tx_buf;
dws->tx_end = dws->tx + transfer->len;
dws->rx = transfer->rx_buf;
dws->rx_end = dws->rx + transfer->len;
dws->write = dws->tx ? chip->write : null_writer;
dws->read = dws->rx ? chip->read : null_reader;
dws->cs_change = transfer->cs_change;
dws->len = dws->cur_transfer->len;
if (chip != dws->prev_chip)
cs_change = 1;
cr0 = chip->cr0;
/* Handle per transfer options for bpw and speed */
if (transfer->speed_hz) {
speed = chip->speed_hz;
if (transfer->speed_hz != speed) {
speed = transfer->speed_hz;
if (speed > dws->max_freq) {
printk(KERN_ERR "MRST SPI0: unsupported"
"freq: %dHz\n", speed);
message->status = -EIO;
goto early_exit;
}
/* clk_div doesn't support odd number */
clk_div = dws->max_freq / speed;
clk_div = (clk_div >> 1) << 1;
chip->speed_hz = speed;
chip->clk_div = clk_div;
}
}
if (transfer->bits_per_word) {
bits = transfer->bits_per_word;
switch (bits) {
case 8:
dws->n_bytes = 1;
dws->dma_width = 1;
dws->read = (dws->read != null_reader) ?
u8_reader : null_reader;
dws->write = (dws->write != null_writer) ?
u8_writer : null_writer;
break;
case 16:
dws->n_bytes = 2;
dws->dma_width = 2;
dws->read = (dws->read != null_reader) ?
u16_reader : null_reader;
dws->write = (dws->write != null_writer) ?
u16_writer : null_writer;
break;
default:
printk(KERN_ERR "MRST SPI0: unsupported bits:"
"%db\n", bits);
message->status = -EIO;
goto early_exit;
}
cr0 = (bits - 1)
| (chip->type << SPI_FRF_OFFSET)
| (spi->mode << SPI_MODE_OFFSET)
| (chip->tmode << SPI_TMOD_OFFSET);
}
message->state = RUNNING_STATE;
/* Check if current transfer is a DMA transaction */
dws->dma_mapped = map_dma_buffers(dws);
if (!dws->dma_mapped && !chip->poll_mode) {
if (dws->rx)
imask |= SPI_INT_RXFI;
if (dws->tx)
imask |= SPI_INT_TXEI;
dws->transfer_handler = interrupt_transfer;
}
/*
* Reprogram registers only if
* 1. chip select changes
* 2. clk_div is changed
* 3. control value changes
*/
if (dw_readw(dws, ctrl0) != cr0 || cs_change || clk_div) {
spi_enable_chip(dws, 0);
if (dw_readw(dws, ctrl0) != cr0)
dw_writew(dws, ctrl0, cr0);
/* Set the interrupt mask, for poll mode just diable all int */
spi_mask_intr(dws, 0xff);
if (!chip->poll_mode)
spi_umask_intr(dws, imask);
spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
spi_chip_sel(dws, spi->chip_select);
spi_enable_chip(dws, 1);
if (cs_change)
dws->prev_chip = chip;
}
if (dws->dma_mapped)
dma_transfer(dws, cs_change);
if (chip->poll_mode)
poll_transfer(dws);
return;
early_exit:
giveback(dws);
return;
}
static void pump_messages(struct work_struct *work)
{
struct dw_spi *dws =
container_of(work, struct dw_spi, pump_messages);
unsigned long flags;
/* Lock queue and check for queue work */
spin_lock_irqsave(&dws->lock, flags);
if (list_empty(&dws->queue) || dws->run == QUEUE_STOPPED) {
dws->busy = 0;
spin_unlock_irqrestore(&dws->lock, flags);
return;
}
/* Make sure we are not already running a message */
if (dws->cur_msg) {
spin_unlock_irqrestore(&dws->lock, flags);
return;
}
/* Extract head of queue */
dws->cur_msg = list_entry(dws->queue.next, struct spi_message, queue);
list_del_init(&dws->cur_msg->queue);
/* Initial message state*/
dws->cur_msg->state = START_STATE;
dws->cur_transfer = list_entry(dws->cur_msg->transfers.next,
struct spi_transfer,
transfer_list);
dws->cur_chip = spi_get_ctldata(dws->cur_msg->spi);
/* Mark as busy and launch transfers */
tasklet_schedule(&dws->pump_transfers);
dws->busy = 1;
spin_unlock_irqrestore(&dws->lock, flags);
}
/* spi_device use this to queue in their spi_msg */
static int dw_spi_transfer(struct spi_device *spi, struct spi_message *msg)
{
struct dw_spi *dws = spi_master_get_devdata(spi->master);
unsigned long flags;
spin_lock_irqsave(&dws->lock, flags);
if (dws->run == QUEUE_STOPPED) {
spin_unlock_irqrestore(&dws->lock, flags);
return -ESHUTDOWN;
}
msg->actual_length = 0;
msg->status = -EINPROGRESS;
msg->state = START_STATE;
list_add_tail(&msg->queue, &dws->queue);
if (dws->run == QUEUE_RUNNING && !dws->busy) {
if (dws->cur_transfer || dws->cur_msg)
queue_work(dws->workqueue,
&dws->pump_messages);
else {
/* If no other data transaction in air, just go */
spin_unlock_irqrestore(&dws->lock, flags);
pump_messages(&dws->pump_messages);
return 0;
}
}
spin_unlock_irqrestore(&dws->lock, flags);
return 0;
}
/* This may be called twice for each spi dev */
static int dw_spi_setup(struct spi_device *spi)
{
struct dw_spi_chip *chip_info = NULL;
struct chip_data *chip;
if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
return -EINVAL;
/* Only alloc on first setup */
chip = spi_get_ctldata(spi);
if (!chip) {
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->cs_control = null_cs_control;
chip->enable_dma = 0;
}
/*
* Protocol drivers may change the chip settings, so...
* if chip_info exists, use it
*/
chip_info = spi->controller_data;
/* chip_info doesn't always exist */
if (chip_info) {
if (chip_info->cs_control)
chip->cs_control = chip_info->cs_control;
chip->poll_mode = chip_info->poll_mode;
chip->type = chip_info->type;
chip->rx_threshold = 0;
chip->tx_threshold = 0;
chip->enable_dma = chip_info->enable_dma;
}
if (spi->bits_per_word <= 8) {
chip->n_bytes = 1;
chip->dma_width = 1;
chip->read = u8_reader;
chip->write = u8_writer;
} else if (spi->bits_per_word <= 16) {
chip->n_bytes = 2;
chip->dma_width = 2;
chip->read = u16_reader;
chip->write = u16_writer;
} else {
/* Never take >16b case for MRST SPIC */
dev_err(&spi->dev, "invalid wordsize\n");
return -EINVAL;
}
chip->bits_per_word = spi->bits_per_word;
chip->speed_hz = spi->max_speed_hz;
if (chip->speed_hz)
chip->clk_div = 25000000 / chip->speed_hz;
else
chip->clk_div = 8; /* default value */
chip->tmode = 0; /* Tx & Rx */
/* Default SPI mode is SCPOL = 0, SCPH = 0 */
chip->cr0 = (chip->bits_per_word - 1)
| (chip->type << SPI_FRF_OFFSET)
| (spi->mode << SPI_MODE_OFFSET)
| (chip->tmode << SPI_TMOD_OFFSET);
spi_set_ctldata(spi, chip);
return 0;
}
static void dw_spi_cleanup(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata(spi);
kfree(chip);
}
static int __init init_queue(struct dw_spi *dws)
{
INIT_LIST_HEAD(&dws->queue);
spin_lock_init(&dws->lock);
dws->run = QUEUE_STOPPED;
dws->busy = 0;
tasklet_init(&dws->pump_transfers,
pump_transfers, (unsigned long)dws);
INIT_WORK(&dws->pump_messages, pump_messages);
dws->workqueue = create_singlethread_workqueue(
dev_name(dws->master->dev.parent));
if (dws->workqueue == NULL)
return -EBUSY;
return 0;
}
static int start_queue(struct dw_spi *dws)
{
unsigned long flags;
spin_lock_irqsave(&dws->lock, flags);
if (dws->run == QUEUE_RUNNING || dws->busy) {
spin_unlock_irqrestore(&dws->lock, flags);
return -EBUSY;
}
dws->run = QUEUE_RUNNING;
dws->cur_msg = NULL;
dws->cur_transfer = NULL;
dws->cur_chip = NULL;
dws->prev_chip = NULL;
spin_unlock_irqrestore(&dws->lock, flags);
queue_work(dws->workqueue, &dws->pump_messages);
return 0;
}
static int stop_queue(struct dw_spi *dws)
{
unsigned long flags;
unsigned limit = 50;
int status = 0;
spin_lock_irqsave(&dws->lock, flags);
dws->run = QUEUE_STOPPED;
while (!list_empty(&dws->queue) && dws->busy && limit--) {
spin_unlock_irqrestore(&dws->lock, flags);
msleep(10);
spin_lock_irqsave(&dws->lock, flags);
}
if (!list_empty(&dws->queue) || dws->busy)
status = -EBUSY;
spin_unlock_irqrestore(&dws->lock, flags);
return status;
}
static int destroy_queue(struct dw_spi *dws)
{
int status;
status = stop_queue(dws);
if (status != 0)
return status;
destroy_workqueue(dws->workqueue);
return 0;
}
/* Restart the controller, disable all interrupts, clean rx fifo */
static void spi_hw_init(struct dw_spi *dws)
{
spi_enable_chip(dws, 0);
spi_mask_intr(dws, 0xff);
spi_enable_chip(dws, 1);
flush(dws);
}
int __devinit dw_spi_add_host(struct dw_spi *dws)
{
struct spi_master *master;
int ret;
BUG_ON(dws == NULL);
master = spi_alloc_master(dws->parent_dev, 0);
if (!master) {
ret = -ENOMEM;
goto exit;
}
dws->master = master;
dws->type = SSI_MOTO_SPI;
dws->prev_chip = NULL;
dws->dma_inited = 0;
dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
ret = request_irq(dws->irq, dw_spi_irq, 0,
"dw_spi", dws);
if (ret < 0) {
dev_err(&master->dev, "can not get IRQ\n");
goto err_free_master;
}
master->mode_bits = SPI_CPOL | SPI_CPHA;
master->bus_num = dws->bus_num;
master->num_chipselect = dws->num_cs;
master->cleanup = dw_spi_cleanup;
master->setup = dw_spi_setup;
master->transfer = dw_spi_transfer;
dws->dma_inited = 0;
/* Basic HW init */
spi_hw_init(dws);
/* Initial and start queue */
ret = init_queue(dws);
if (ret) {
dev_err(&master->dev, "problem initializing queue\n");
goto err_diable_hw;
}
ret = start_queue(dws);
if (ret) {
dev_err(&master->dev, "problem starting queue\n");
goto err_diable_hw;
}
spi_master_set_devdata(master, dws);
ret = spi_register_master(master);
if (ret) {
dev_err(&master->dev, "problem registering spi master\n");
goto err_queue_alloc;
}
mrst_spi_debugfs_init(dws);
return 0;
err_queue_alloc:
destroy_queue(dws);
err_diable_hw:
spi_enable_chip(dws, 0);
free_irq(dws->irq, dws);
err_free_master:
spi_master_put(master);
exit:
return ret;
}
EXPORT_SYMBOL(dw_spi_add_host);
void __devexit dw_spi_remove_host(struct dw_spi *dws)
{
int status = 0;
if (!dws)
return;
mrst_spi_debugfs_remove(dws);
/* Remove the queue */
status = destroy_queue(dws);
if (status != 0)
dev_err(&dws->master->dev, "dw_spi_remove: workqueue will not "
"complete, message memory not freed\n");
spi_enable_chip(dws, 0);
/* Disable clk */
spi_set_clk(dws, 0);
free_irq(dws->irq, dws);
/* Disconnect from the SPI framework */
spi_unregister_master(dws->master);
}
int dw_spi_suspend_host(struct dw_spi *dws)
{
int ret = 0;
ret = stop_queue(dws);
if (ret)
return ret;
spi_enable_chip(dws, 0);
spi_set_clk(dws, 0);
return ret;
}
EXPORT_SYMBOL(dw_spi_suspend_host);
int dw_spi_resume_host(struct dw_spi *dws)
{
int ret;
spi_hw_init(dws);
ret = start_queue(dws);
if (ret)
dev_err(&dws->master->dev, "fail to start queue (%d)\n", ret);
return ret;
}
EXPORT_SYMBOL(dw_spi_resume_host);
MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");
MODULE_LICENSE("GPL v2");

169
drivers/spi/dw_spi_pci.c Normal file
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@ -0,0 +1,169 @@
/*
* mrst_spi_pci.c - PCI interface driver for DW SPI Core
*
* Copyright (c) 2009, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/spi/dw_spi.h>
#include <linux/spi/spi.h>
#define DRIVER_NAME "dw_spi_pci"
struct dw_spi_pci {
struct pci_dev *pdev;
struct dw_spi dws;
};
static int __devinit spi_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
struct dw_spi_pci *dwpci;
struct dw_spi *dws;
int pci_bar = 0;
int ret;
printk(KERN_INFO "DW: found PCI SPI controller(ID: %04x:%04x)\n",
pdev->vendor, pdev->device);
ret = pci_enable_device(pdev);
if (ret)
return ret;
dwpci = kzalloc(sizeof(struct dw_spi_pci), GFP_KERNEL);
if (!dwpci) {
ret = -ENOMEM;
goto err_disable;
}
dwpci->pdev = pdev;
dws = &dwpci->dws;
/* Get basic io resource and map it */
dws->paddr = pci_resource_start(pdev, pci_bar);
dws->iolen = pci_resource_len(pdev, pci_bar);
ret = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
if (ret)
goto err_kfree;
dws->regs = ioremap_nocache((unsigned long)dws->paddr,
pci_resource_len(pdev, pci_bar));
if (!dws->regs) {
ret = -ENOMEM;
goto err_release_reg;
}
dws->parent_dev = &pdev->dev;
dws->bus_num = 0;
dws->num_cs = 4;
dws->max_freq = 25000000; /* for Moorestwon */
dws->irq = pdev->irq;
ret = dw_spi_add_host(dws);
if (ret)
goto err_unmap;
/* PCI hook and SPI hook use the same drv data */
pci_set_drvdata(pdev, dwpci);
return 0;
err_unmap:
iounmap(dws->regs);
err_release_reg:
pci_release_region(pdev, pci_bar);
err_kfree:
kfree(dwpci);
err_disable:
pci_disable_device(pdev);
return ret;
}
static void __devexit spi_pci_remove(struct pci_dev *pdev)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
pci_set_drvdata(pdev, NULL);
iounmap(dwpci->dws.regs);
pci_release_region(pdev, 0);
kfree(dwpci);
pci_disable_device(pdev);
}
#ifdef CONFIG_PM
static int spi_suspend(struct pci_dev *pdev, pm_message_t state)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
int ret;
ret = dw_spi_suspend_host(&dwpci->dws);
if (ret)
return ret;
pci_save_state(pdev);
pci_disable_device(pdev);
pci_set_power_state(pdev, pci_choose_state(pdev, state));
return ret;
}
static int spi_resume(struct pci_dev *pdev)
{
struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
int ret;
pci_set_power_state(pdev, PCI_D0);
pci_restore_state(pdev);
ret = pci_enable_device(pdev);
if (ret)
return ret;
return dw_spi_resume_host(&dwpci->dws);
}
#else
#define spi_suspend NULL
#define spi_resume NULL
#endif
static const struct pci_device_id pci_ids[] __devinitdata = {
/* Intel Moorestown platform SPI controller 0 */
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0800) },
{},
};
static struct pci_driver dw_spi_driver = {
.name = DRIVER_NAME,
.id_table = pci_ids,
.probe = spi_pci_probe,
.remove = __devexit_p(spi_pci_remove),
.suspend = spi_suspend,
.resume = spi_resume,
};
static int __init mrst_spi_init(void)
{
return pci_register_driver(&dw_spi_driver);
}
static void __exit mrst_spi_exit(void)
{
pci_unregister_driver(&dw_spi_driver);
}
module_init(mrst_spi_init);
module_exit(mrst_spi_exit);
MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
MODULE_DESCRIPTION("PCI interface driver for DW SPI Core");
MODULE_LICENSE("GPL v2");

212
include/linux/spi/dw_spi.h Normal file
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@ -0,0 +1,212 @@
#ifndef DW_SPI_HEADER_H
#define DW_SPI_HEADER_H
#include <linux/io.h>
/* Bit fields in CTRLR0 */
#define SPI_DFS_OFFSET 0
#define SPI_FRF_OFFSET 4
#define SPI_FRF_SPI 0x0
#define SPI_FRF_SSP 0x1
#define SPI_FRF_MICROWIRE 0x2
#define SPI_FRF_RESV 0x3
#define SPI_MODE_OFFSET 6
#define SPI_SCPH_OFFSET 6
#define SPI_SCOL_OFFSET 7
#define SPI_TMOD_OFFSET 8
#define SPI_TMOD_TR 0x0 /* xmit & recv */
#define SPI_TMOD_TO 0x1 /* xmit only */
#define SPI_TMOD_RO 0x2 /* recv only */
#define SPI_TMOD_EPROMREAD 0x3 /* eeprom read mode */
#define SPI_SLVOE_OFFSET 10
#define SPI_SRL_OFFSET 11
#define SPI_CFS_OFFSET 12
/* Bit fields in SR, 7 bits */
#define SR_MASK 0x7f /* cover 7 bits */
#define SR_BUSY (1 << 0)
#define SR_TF_NOT_FULL (1 << 1)
#define SR_TF_EMPT (1 << 2)
#define SR_RF_NOT_EMPT (1 << 3)
#define SR_RF_FULL (1 << 4)
#define SR_TX_ERR (1 << 5)
#define SR_DCOL (1 << 6)
/* Bit fields in ISR, IMR, RISR, 7 bits */
#define SPI_INT_TXEI (1 << 0)
#define SPI_INT_TXOI (1 << 1)
#define SPI_INT_RXUI (1 << 2)
#define SPI_INT_RXOI (1 << 3)
#define SPI_INT_RXFI (1 << 4)
#define SPI_INT_MSTI (1 << 5)
/* TX RX interrupt level threshhold, max can be 256 */
#define SPI_INT_THRESHOLD 32
enum dw_ssi_type {
SSI_MOTO_SPI = 0,
SSI_TI_SSP,
SSI_NS_MICROWIRE,
};
struct dw_spi_reg {
u32 ctrl0;
u32 ctrl1;
u32 ssienr;
u32 mwcr;
u32 ser;
u32 baudr;
u32 txfltr;
u32 rxfltr;
u32 txflr;
u32 rxflr;
u32 sr;
u32 imr;
u32 isr;
u32 risr;
u32 txoicr;
u32 rxoicr;
u32 rxuicr;
u32 msticr;
u32 icr;
u32 dmacr;
u32 dmatdlr;
u32 dmardlr;
u32 idr;
u32 version;
u32 dr; /* Currently oper as 32 bits,
though only low 16 bits matters */
} __packed;
struct dw_spi {
struct spi_master *master;
struct spi_device *cur_dev;
struct device *parent_dev;
enum dw_ssi_type type;
void __iomem *regs;
unsigned long paddr;
u32 iolen;
int irq;
u32 max_freq; /* max bus freq supported */
u16 bus_num;
u16 num_cs; /* supported slave numbers */
/* Driver message queue */
struct workqueue_struct *workqueue;
struct work_struct pump_messages;
spinlock_t lock;
struct list_head queue;
int busy;
int run;
/* Message Transfer pump */
struct tasklet_struct pump_transfers;
/* Current message transfer state info */
struct spi_message *cur_msg;
struct spi_transfer *cur_transfer;
struct chip_data *cur_chip;
struct chip_data *prev_chip;
size_t len;
void *tx;
void *tx_end;
void *rx;
void *rx_end;
int dma_mapped;
dma_addr_t rx_dma;
dma_addr_t tx_dma;
size_t rx_map_len;
size_t tx_map_len;
u8 n_bytes; /* current is a 1/2 bytes op */
u8 max_bits_per_word; /* maxim is 16b */
u32 dma_width;
int cs_change;
int (*write)(struct dw_spi *dws);
int (*read)(struct dw_spi *dws);
irqreturn_t (*transfer_handler)(struct dw_spi *dws);
void (*cs_control)(u32 command);
/* Dma info */
int dma_inited;
struct dma_chan *txchan;
struct dma_chan *rxchan;
int txdma_done;
int rxdma_done;
u64 tx_param;
u64 rx_param;
struct device *dma_dev;
dma_addr_t dma_addr;
/* Bus interface info */
void *priv;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs;
#endif
};
#define dw_readl(dw, name) \
__raw_readl(&(((struct dw_spi_reg *)dw->regs)->name))
#define dw_writel(dw, name, val) \
__raw_writel((val), &(((struct dw_spi_reg *)dw->regs)->name))
#define dw_readw(dw, name) \
__raw_readw(&(((struct dw_spi_reg *)dw->regs)->name))
#define dw_writew(dw, name, val) \
__raw_writew((val), &(((struct dw_spi_reg *)dw->regs)->name))
static inline void spi_enable_chip(struct dw_spi *dws, int enable)
{
dw_writel(dws, ssienr, (enable ? 1 : 0));
}
static inline void spi_set_clk(struct dw_spi *dws, u16 div)
{
dw_writel(dws, baudr, div);
}
static inline void spi_chip_sel(struct dw_spi *dws, u16 cs)
{
if (cs > dws->num_cs)
return;
dw_writel(dws, ser, 1 << cs);
}
/* Disable IRQ bits */
static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)
{
u32 new_mask;
new_mask = dw_readl(dws, imr) & ~mask;
dw_writel(dws, imr, new_mask);
}
/* Enable IRQ bits */
static inline void spi_umask_intr(struct dw_spi *dws, u32 mask)
{
u32 new_mask;
new_mask = dw_readl(dws, imr) | mask;
dw_writel(dws, imr, new_mask);
}
/*
* Each SPI slave device to work with dw_api controller should
* has such a structure claiming its working mode (PIO/DMA etc),
* which can be save in the "controller_data" member of the
* struct spi_device
*/
struct dw_spi_chip {
u8 poll_mode; /* 0 for contoller polling mode */
u8 type; /* SPI/SSP/Micrwire */
u8 enable_dma;
void (*cs_control)(u32 command);
};
extern int dw_spi_add_host(struct dw_spi *dws);
extern void dw_spi_remove_host(struct dw_spi *dws);
extern int dw_spi_suspend_host(struct dw_spi *dws);
extern int dw_spi_resume_host(struct dw_spi *dws);
#endif /* DW_SPI_HEADER_H */