1.需求：通过gsip引脚接收来自fpga的数据等待接收中断，然后中断到来后，113的spi驱动为主控读取fpga的spi数据，数据量12800字节，驱动设置了10个缓冲区映射内存，spi内次写入一个缓冲区。中断频率为25Hz。应用程序通过map映射会读取存在的10个里面的ok的缓冲区。
2.现状：驱动代码基于imx6ull linux4.9版本修改，驱动已经编译通过，并且可以使用read、write接口正常的进行spi通讯（1000字节以内）。但是如果是使用GPIS中断函数来完成spi的读取，调用同样的spi读写函数，spi不能正常工作，会提示：“Bufferless transfer has length ”，错误来自spi.c。（注意，gpio中断是fpga的引脚给T113的引脚，代码中通过中断函数触发spi的一次传输）
3.驱动文件是：fsfpgain.c；read、write测试app是：test_spidev.c；gpio中断来读取spi测试app是：test_fsfpgain.c
下面是三个文件的代码：
fsfpgain.c
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/gpio.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/of_gpio.h>
#include <linux/semaphore.h>
#include <linux/timer.h>
#include <linux/spi/spi.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/atomic.h>
#include <linux/irq.h>
#include <linux/of_irq.h>
#include <asm/mach/map.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <linux/spi/spi.h>
#include <linux/spi/spidev.h>
#include <linux/acpi.h>
#include <linux/of_irq.h>
#include <asm/mach/map.h>
#include <asm/uaccess.h>
#include <asm/io.h>
/*
* This supports access to SPI devices using normal userspace I/O calls.
* Note that while traditional UNIX/POSIX I/O semantics are half duplex,
* and often mask message boundaries, full SPI support requires full duplex
* transfers. There are several kinds of internal message boundaries to
* handle chipselect management and other protocol options.
*
* SPI has a character major number assigned. We allocate minor numbers
* dynamically using a bitmask. You must use hotplug tools, such as udev
* (or mdev with busybox) to create and destroy the /dev/spidevB.C device
* nodes, since there is no fixed association of minor numbers with any
* particular SPI bus or device.
*/
#define SPIDEV_MAJOR 153 /* assigned */
#define N_SPI_MINORS 32 /* ... up to 256 */
static DECLARE_BITMAP(minors, N_SPI_MINORS);
/* Bit masks for spi_device.mode management. Note that incorrect
* settings for some settings can cause *lots* of trouble for other
* devices on a shared bus:
*
* - CS_HIGH ... this device will be active when it shouldn't be
* - 3WIRE ... when active, it won't behave as it should
* - NO_CS ... there will be no explicit message boundaries; this
* is completely incompatible with the shared bus model
* - READY ... transfers may proceed when they shouldn't.
*
* REVISIT should changing those flags be privileged?
*/
#define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \
| SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP \
| SPI_NO_CS | SPI_READY | SPI_TX_DUAL \
| SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)
#define DMAC_CNLL_MAX_NUM 32
#define DMAC_ONE_TR_NUM 1000 //一次spi从fpga读取的大小
#define DMAC_MAX_TRF_SIZE DMAC_CNLL_MAX_NUM*DMAC_ONE_TR_NUM
#define DMA_RECV_MAX_NUM 10//环形缓冲器大小
#define VER 0x20000113
#define NEXT_BUF(x) (((x+1) < DMA_RECV_MAX_NUM) ? (x+1) : 0)
struct mem_addr{
char* v_adr;
dma_addr_t p_adr;
};//内存物理地址和虚拟地址
//环形缓冲器，分块保存每个dma头物理地址
struct buffer_cut{
unsigned int recv_num;
unsigned int last_buf_len;//最后一块内存的长度
dma_addr_t pr_buf_fpga[DMA_RECV_MAX_NUM][DMAC_CNLL_MAX_NUM];
};
struct spidev_data {
dev_t devt;
spinlock_t spi_lock;
struct spi_device *spi;
struct list_head device_entry;
/* TX/RX buffers are NULL unless this device is open (users > 0) */
struct mutex buf_lock;
unsigned users;
u8 *tx_buffer;
u8 *rx_buffer;
u32 speed_hz;
/*connet app param*/
struct spi_transfer t;
struct spi_message m;
struct buffer_cut *buf_cut;
int irq_gpio;
int irq_num; //fpga中断号
struct mem_addr rxbuf;
int spi_len;//spi dma 单次长度
bool b_workflag;//工作状态
bool b_printk;//调试打印状态
unsigned int send_data_len;//与fpga通讯一次交换数据的长度
struct semaphore spi_sema;//信号量 表示环形缓冲区内的可读数据量
int recv_buf_no;//接收到的数据块号码
int copy_recv_buf_no;//被复制的“接收到的数据块号码”防止被中断修改数据
int read_buf_no;//可读取的数据块号码
};
static LIST_HEAD(device_list);
static DEFINE_MUTEX(device_list_lock);
static void init_p_buf_cut(struct spidev_data *spidev);
static unsigned bufsiz = 40960;
module_param(bufsiz, uint, S_IRUGO);
MODULE_PARM_DESC(bufsiz, "data bytes in biggest supported SPI message");
/*-------------------------------------------------------------------------*/
/*add shiguojie */
static inline ssize_t
spidev_sync_write(struct spidev_data *spidev, size_t len);
static ssize_t
spidev_sync(struct spidev_data *spidev)
{
int status;
struct spi_device *spi;
spin_lock_irq(&spidev->spi_lock);
spi = spidev->spi;
spin_unlock_irq(&spidev->spi_lock);
if (spi == NULL)
status = -ESHUTDOWN;
else
status = spi_sync(spi, &spidev->m);
printk("fsfpgain: spidev_sync re-%d\n",status);
if (status == 0)
status = spidev->m.actual_length;
printk("fsfpgain: spidev_sync %d-%d-%d\n",spidev->t.speed_hz,spidev->t.len,status);
return status;
}
static inline ssize_t
spidev_sync_read(struct spidev_data *spidev, size_t len)
{
struct spi_transfer t = {
.rx_buf = spidev->rx_buffer,
.len = len,
.speed_hz = spidev->speed_hz,
};
spi_message_init(&spidev->m);
spi_message_add_tail(&t, &spidev->m);
return spidev_sync(spidev);
}
static void spi_fpga_recv(struct spidev_data* spidev)
{
int i = 0;
int status = -1;
struct buffer_cut *_p = spidev->buf_cut;
int _no = spidev->recv_buf_no;
//gpio_set_value(fsfpgaindev.cs_gpio, 0);
printk("fafpgain:spi_fpga_recv %d-%d",_p->recv_num,spidev->buf_cut->last_buf_len);
mutex_lock(&spidev->buf_lock);
for (i = 0; i < _p->recv_num; i++)
{
spidev_sync_write(spidev,DMAC_ONE_TR_NUM);
memcpy((void*)spidev->buf_cut->pr_buf_fpga[_no][i],spidev->rx_buffer,DMAC_ONE_TR_NUM);
}
if(spidev->buf_cut->last_buf_len)
{
spidev_sync_read(spidev,spidev->buf_cut->last_buf_len);
memcpy((void*)spidev->buf_cut->pr_buf_fpga[_no][i],spidev->rx_buffer,spidev->buf_cut->last_buf_len);
}
mutex_unlock(&spidev->buf_lock);
}
static irqreturn_t irq_gpio_spi_handler(int irq, void *dev_id)
{
//printk("irq_gpio_spi_handler run\r\n");
return IRQ_WAKE_THREAD;
}
static irqreturn_t irq_gpio_spi_thread_func(int irq, void *data)
{
struct spidev_data *spidev = (struct spidev_data*)data;
if(spidev->b_workflag)
{
printk("fsfpgain:irq_gpio rec buf[%d],add:%x\r\n",
spidev->recv_buf_no,spidev->buf_cut->pr_buf_fpga[spidev->recv_buf_no][0]);
spi_fpga_recv(spidev);//读取一次
//fsfpgaindev.read_buf_no = fsfpgaindev.recv_buf_no;
spidev->recv_buf_no = NEXT_BUF(spidev->recv_buf_no);//取出下个环形缓冲器编号
up(&spidev->spi_sema);
spidev->b_workflag = 0;//test
}
return IRQ_HANDLED;
}
void setSpidev_data(struct spidev_data *spidev)
{
int ret = 0;
spidev->speed_hz = 10000000;
spidev->t.speed_hz = spidev->speed_hz;
spidev->b_workflag = 0;//初始化工作状态为不工作
spidev->send_data_len = 0;//初始化spi收发数据长度为0
spidev->recv_buf_no = 0;
spidev->read_buf_no = 0;
spidev->copy_recv_buf_no = 0;
spidev->spi->mode = SPI_MODE_1;
ret = spi_setup(spidev->spi);
printk("fsfpgain:spi_setup re:%d\n",ret);
//set map
spidev->buf_cut = kzalloc(sizeof(struct buffer_cut), GFP_KERNEL);
printk("fsfpgain:rxvadr value:0x%lx padr:0x%x\r\n",(long)spidev->rxbuf.v_adr,spidev->rxbuf.p_adr);
printk("fsfpgain:rxvadr addr:0x%lx padr:0x%x\r\n",(long)&spidev->rxbuf.v_adr,&spidev->rxbuf.p_adr);
if((dma_set_coherent_mask(&spidev->spi->dev,DMA_BIT_MASK(32))) != 0)
{
dev_err(&spidev->spi->dev,"Failed to set 32-bit DMA mask\n");
return -ENODEV;
}
spidev->rxbuf.v_adr = dma_alloc_coherent(&spidev->spi->dev,DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM,&spidev->rxbuf.p_adr,GFP_KERNEL|GFP_DMA);
//set irq
struct device_node *nd = of_get_parent(spidev->spi->dev.of_node);
struct device_node *child;
if(NULL == nd){
printk("fsfpgain:nd get error\r\n");
}else
{
printk("fsfpgain:Child scan\r\n");
for_each_child_of_node(nd, child)
{
printk("Child node name: %s\r\n", of_node_full_name(child));
break;
}
}
spidev->irq_gpio = of_get_named_gpio(child, "irq-gpio", 0);
if (spidev->irq_gpio < 0)
{
printk("fsfpgaindev.irq_gpio get error\r\n");
}
ret = gpio_request(spidev->irq_gpio, "irq_gpio");
if(0 == ret)
printk("fsfpgain:gpio request irq gpio ok\r\n");
else
printk("fsfpgain:gpio request ret:%d\r\n",ret);
gpio_direction_input(spidev->irq_gpio);
spidev->irq_num = gpio_to_irq(spidev->irq_gpio);
ret = request_threaded_irq(spidev->irq_num, irq_gpio_spi_handler,irq_gpio_spi_thread_func,IRQF_TRIGGER_RISING, "irq_gpio", spidev);
if(0 > ret)
{
printk("request_irq error\r\n");
}
else
{
printk("fsfpgain irq_num:%d\n",spidev->irq_num);
}
return;
}
void resetSpidev_data(struct spidev_data *spidev)
{
free_irq(spidev->irq_num, spidev);
gpio_direction_output(spidev->irq_gpio, 0);
gpio_free(spidev->irq_gpio);
printk("fsfpgain:gpio_free\r\n");
kfree(spidev->buf_cut);
dma_free_coherent(&spidev->spi->dev,DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM,spidev->rxbuf.v_adr, spidev->rxbuf.p_adr);
}
/*add shiguojie end*/
static inline ssize_t
spidev_sync_write(struct spidev_data *spidev, size_t len)
{
struct spi_transfer t = {
.tx_buf = spidev->tx_buffer,
.rx_buf = spidev->rx_buffer,//add by shiguojie
.len = len,
.speed_hz = spidev->speed_hz,
};
printk("fsfpgain:transfer len-%d speed-%d\r\n",len,spidev->speed_hz);
spi_message_init(&spidev->m);
spi_message_add_tail(&t, &spidev->m);
return spidev_sync(spidev);
}
/*-------------------------------------------------------------------------*/
/* Read-only message with current device setup */
static ssize_t
spidev_read(struct file *filp, char __user *buf, size_t count, loff_t *f_pos)
{
struct spidev_data *spidev;
ssize_t status = 0;
/* chipselect only toggles at start or end of operation */
if (count > bufsiz)
return -EMSGSIZE;
spidev = filp->private_data;
mutex_lock(&spidev->buf_lock);
status = spidev_sync_read(spidev, count);
if (status > 0) {
unsigned long missing;
missing = copy_to_user(buf, spidev->rx_buffer, status);
if (missing == status)
status = -EFAULT;
else
status = status - missing;
}
mutex_unlock(&spidev->buf_lock);
return status;
}
/* Write-only message with current device setup */
static ssize_t
spidev_write(struct file *filp, const char __user *buf,
size_t count, loff_t *f_pos)
{
int x = 0;
struct spidev_data *spidev;
ssize_t status = 0;
unsigned long missing;
/* chipselect only toggles at start or end of operation */
if (count > bufsiz)
return -EMSGSIZE;
spidev = filp->private_data;
mutex_lock(&spidev->buf_lock);
char ttempBuf[1000];
char rtempBuf[1000];
spidev->tx_buffer = ttempBuf;
spidev->rx_buffer = rtempBuf;
missing = copy_from_user(spidev->tx_buffer, buf, count);
if (missing == 0)
{
spidev_sync_write(spidev, count);
}
else
status = -EFAULT;
mutex_unlock(&spidev->buf_lock);
printk("fsfpgain:write read:%s\n",spidev->rx_buffer);
return status;
}
static int spidev_message(struct spidev_data *spidev,
struct spi_ioc_transfer *u_xfers, unsigned n_xfers)
{
struct spi_transfer *k_xfers;
struct spi_transfer *k_tmp;
struct spi_ioc_transfer *u_tmp;
unsigned n, total, tx_total, rx_total;
u8 *tx_buf, *rx_buf;
int status = -EFAULT;
spi_message_init(&spidev->m);
k_xfers = kcalloc(n_xfers, sizeof(*k_tmp), GFP_KERNEL);
if (k_xfers == NULL)
return -ENOMEM;
/* Construct spi_message, copying any tx data to bounce buffer.
* We walk the array of user-provided transfers, using each one
* to initialize a kernel version of the same transfer.
*/
tx_buf = spidev->tx_buffer;
rx_buf = spidev->rx_buffer;
total = 0;
tx_total = 0;
rx_total = 0;
for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
n;
n--, k_tmp++, u_tmp++) {
/* Ensure that also following allocations from rx_buf/tx_buf will meet
* DMA alignment requirements.
*/
unsigned int len_aligned = ALIGN(u_tmp->len, ARCH_KMALLOC_MINALIGN);
k_tmp->len = u_tmp->len;
total += k_tmp->len;
/* Since the function returns the total length of transfers
* on success, restrict the total to positive int values to
* avoid the return value looking like an error. Also check
* each transfer length to avoid arithmetic overflow.
*/
if (total > INT_MAX || k_tmp->len > INT_MAX) {
status = -EMSGSIZE;
goto done;
}
if (u_tmp->rx_buf) {
/* this transfer needs space in RX bounce buffer */
rx_total += len_aligned;
if (rx_total > bufsiz) {
status = -EMSGSIZE;
goto done;
}
k_tmp->rx_buf = rx_buf;
rx_buf += len_aligned;
}
if (u_tmp->tx_buf) {
/* this transfer needs space in TX bounce buffer */
tx_total += len_aligned;
if (tx_total > bufsiz) {
status = -EMSGSIZE;
goto done;
}
k_tmp->tx_buf = tx_buf;
if (copy_from_user(tx_buf, (const u8 __user *)
(uintptr_t) u_tmp->tx_buf,
u_tmp->len))
goto done;
tx_buf += len_aligned;
}
k_tmp->cs_change = !!u_tmp->cs_change;
k_tmp->tx_nbits = u_tmp->tx_nbits;
k_tmp->rx_nbits = u_tmp->rx_nbits;
k_tmp->bits_per_word = u_tmp->bits_per_word;
k_tmp->delay_usecs = u_tmp->delay_usecs;
k_tmp->speed_hz = u_tmp->speed_hz;
k_tmp->word_delay_usecs = u_tmp->word_delay_usecs;
if (!k_tmp->speed_hz)
;//k_tmp->speed_hz = spidev->speed_hz;
#ifdef VERBOSE
dev_dbg(&spidev->spi->dev,
" xfer len %u %s%s%s%dbits %u usec %u usec %uHz\n",
u_tmp->len,
u_tmp->rx_buf ? "rx " : "",
u_tmp->tx_buf ? "tx " : "",
u_tmp->cs_change ? "cs " : "",
u_tmp->bits_per_word ? : spidev->spi->bits_per_word,
u_tmp->delay_usecs,
u_tmp->word_delay_usecs,
u_tmp->speed_hz ? : spidev->spi->max_speed_hz);
#endif
spi_message_add_tail(k_tmp, &spidev->m);
}
status = spidev_sync(spidev);
if (status < 0)
goto done;
/* copy any rx data out of bounce buffer */
for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
n;
n--, k_tmp++, u_tmp++) {
if (u_tmp->rx_buf) {
if (copy_to_user((u8 __user *)
(uintptr_t) u_tmp->rx_buf, k_tmp->rx_buf,
u_tmp->len)) {
status = -EFAULT;
goto done;
}
}
}
status = total;
done:
kfree(k_xfers);
return status;
}
static struct spi_ioc_transfer *
spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc,
unsigned *n_ioc)
{
u32 tmp;
/* Check type, command number and direction */
if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC
|| _IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
|| _IOC_DIR(cmd) != _IOC_WRITE)
return ERR_PTR(-ENOTTY);
tmp = _IOC_SIZE(cmd);
if ((tmp % sizeof(struct spi_ioc_transfer)) != 0)
return ERR_PTR(-EINVAL);
*n_ioc = tmp / sizeof(struct spi_ioc_transfer);
if (*n_ioc == 0)
return NULL;
/* copy into scratch area */
return memdup_user(u_ioc, tmp);
}
static long
spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct spidev_data *spidev;
struct spi_device *spi;
u32 tmp;
unsigned n_ioc;
struct spi_ioc_transfer *ioc;
int ret = 0;
int result = 0;//信号量就绪
unsigned long _info = 0;//arg change kernel value
printk("fsfpgain:spidev_ioctl is run:0x%x-0x%x\r\n",cmd,arg);
/* Check type and command number */
// if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC)
// {
// printk("spi is SPI_IOC_MAGIC\r\n");
// return -ENOTTY;
// }
/* guard against device removal before, or while,
* we issue this ioctl.
*/
spidev = filp->private_data;
printk("fsfpgain:spidev addr0x%x-%x;spi addr0x%x-%x\r\n",*spidev,spidev,*spidev->spi,spidev->spi);
spin_lock_irq(&spidev->spi_lock);
spi = spi_dev_get(spidev->spi);
spin_unlock_irq(&spidev->spi_lock);
if (spi == NULL)
{
printk("spi is null\r\n");
return -ESHUTDOWN;
}
/* use the buffer lock here for triple duty:
* - prevent I/O (from us) so calling spi_setup() is safe;
* - prevent concurrent SPI_IOC_WR_* from morphing
* data fields while SPI_IOC_RD_* reads them;
* - SPI_IOC_MESSAGE needs the buffer locked "normally".
*/
mutex_lock(&spidev->buf_lock);
switch (cmd)
{
case 0x100:
ret = 0x20000113;
break;
case 0x309:
spidev->b_workflag = 0;
break;
case 0x307:
ret = DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM;
break;
case 0x306:
ret = DMAC_MAX_TRF_SIZE;
break;
case 0x305:
ret = spidev->send_data_len;
break;
case 0x304:
ret = copy_from_user(&_info, &arg, sizeof(unsigned long));
if (_info)
spidev->b_printk = 1;
else
spidev->b_printk = 0;
break;
case 0x303://开始工作由APP启动工作
spidev->read_buf_no = spidev->recv_buf_no;//重置可读数据块编号为最新接收到的数据块编号？
sema_init(&spidev->spi_sema,0);//初始化信号量
spidev->b_workflag = 1;//开始工作标志
printk("fafpgain start work!\r\n");
ret = 1;
break;
case 0x302://设置spi传输数据大小并返回大小
ret = copy_from_user(&_info, &arg, sizeof(unsigned long));
#ifdef _DEBUG
printk("cmd 0x302 set len:%ld-%ld return :%d\r\n",_info,arg,ret);
#endif
spidev->send_data_len = arg;
ret = spidev->send_data_len;
if(DMAC_MAX_TRF_SIZE < arg)
{//判断设置的一次接收fpga长度是否超出预设内存
ret = -1;
printk("iotcl cmd:%d arg:%ld error\r\n",cmd,_info);
break;
}
init_p_buf_cut(spidev);
break;
case 0x301://应用程序获取一次buf，在此判断是否有buf
#ifdef _DEBUG
printk("test jiffies:%ld\r\n", jiffies);
#endif
result = down_timeout(&spidev->spi_sema,jiffies+msecs_to_jiffies(60));//获取信号
#ifdef _DEBUG
printk("down_temeout result:%d\r\n", result);
#endif
spidev->copy_recv_buf_no = spidev->recv_buf_no;//copy一份当前值
#ifdef _DEBUG
printk("read_no:%d-copy_recv_no:%d\r\n",spidev->read_buf_no,spidev->copy_recv_buf_no);
#endif
if((spidev->read_buf_no != spidev->copy_recv_buf_no) && (0 == result))
{//right
if ((spidev->read_buf_no + 1) % DMA_RECV_MAX_NUM == spidev->copy_recv_buf_no)
{
ret = (spidev->read_buf_no | 0x10000);//不明白什么意思
}else
{
ret = spidev->read_buf_no;
}
spidev->read_buf_no = NEXT_BUF(spidev->read_buf_no);
}
else if (0 != result)
{
ret = -2;
}
else if (spidev->read_buf_no == spidev->copy_recv_buf_no)
{
ret = -3;
}else
{
ret = -4;
}
#ifdef _DEBUG
printk("0x301 ret:%d\r\n",ret);
#endif
break;
}
mutex_unlock(&spidev->buf_lock);
//#ifdef _DEBUGWZG
printk("2121wzg cmd 0x%x arg:%d ret:%d DMAC_MAX_TRF_SIZE:%d \r\n",cmd,arg,ret,DMAC_MAX_TRF_SIZE);
//#endif
spi_dev_put(spi);
return ret;
}
#ifdef CONFIG_COMPAT
static long
spidev_compat_ioc_message(struct file *filp, unsigned int cmd,
unsigned long arg)
{
struct spi_ioc_transfer __user *u_ioc;
int retval = 0;
struct spidev_data *spidev;
struct spi_device *spi;
unsigned n_ioc, n;
struct spi_ioc_transfer *ioc;
u_ioc = (struct spi_ioc_transfer __user *) compat_ptr(arg);
/* guard against device removal before, or while,
* we issue this ioctl.
*/
printk("fsfpgain:spidev_compat_ioc_message\r\n");
spidev = filp->private_data;
spin_lock_irq(&spidev->spi_lock);
spi = spi_dev_get(spidev->spi);
spin_unlock_irq(&spidev->spi_lock);
if (spi == NULL)
return -ESHUTDOWN;
/* SPI_IOC_MESSAGE needs the buffer locked "normally" */
mutex_lock(&spidev->buf_lock);
/* Check message and copy into scratch area */
ioc = spidev_get_ioc_message(cmd, u_ioc, &n_ioc);
if (IS_ERR(ioc)) {
retval = PTR_ERR(ioc);
goto done;
}
if (!ioc)
goto done; /* n_ioc is also 0 */
/* Convert buffer pointers */
for (n = 0; n < n_ioc; n++) {
ioc[n].rx_buf = (uintptr_t) compat_ptr(ioc[n].rx_buf);
ioc[n].tx_buf = (uintptr_t) compat_ptr(ioc[n].tx_buf);
}
/* translate to spi_message, execute */
retval = spidev_message(spidev, ioc, n_ioc);
kfree(ioc);
done:
mutex_unlock(&spidev->buf_lock);
spi_dev_put(spi);
return retval;
}
static long
spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
printk("fsfpgain:spidev_compat_ioctl\r\n");
if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC
&& _IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0))
&& _IOC_DIR(cmd) == _IOC_WRITE)
return spidev_compat_ioc_message(filp, cmd, arg);
return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#else
#define spidev_compat_ioctl NULL
#endif /* CONFIG_COMPAT */
static int spidev_open(struct inode *inode, struct file *filp)
{
struct spidev_data *spidev;
int status = -ENXIO;
mutex_lock(&device_list_lock);
list_for_each_entry(spidev, &device_list, device_entry) {
if (spidev->devt == inode->i_rdev) {
status = 0;
break;
}
}
if (status) {
pr_debug("spidev: nothing for minor %d\n", iminor(inode));
goto err_find_dev;
}
spidev->users++;
filp->private_data = spidev;
stream_open(inode, filp);
mutex_unlock(&device_list_lock);
return 0;
err_alloc_rx_buf:
kfree(spidev->tx_buffer);
spidev->tx_buffer = NULL;
err_find_dev:
mutex_unlock(&device_list_lock);
return status;
}
static int spidev_release(struct inode *inode, struct file *filp)
{
struct spidev_data *spidev;
int dofree;
mutex_lock(&device_list_lock);
spidev = filp->private_data;
filp->private_data = NULL;
spin_lock_irq(&spidev->spi_lock);
/* ... after we unbound from the underlying device? */
dofree = (spidev->spi == NULL);
spin_unlock_irq(&spidev->spi_lock);
/* last close? */
spidev->users--;
if (!spidev->users) {
//kfree(spidev->tx_buffer);
spidev->tx_buffer = NULL;
//kfree(spidev->rx_buffer);
spidev->rx_buffer = NULL;
if (dofree)
kfree(spidev);
else
;//spidev->speed_hz = spidev->spi->max_speed_hz;
}
#ifdef CONFIG_SPI_SLAVE
if (!dofree)
spi_slave_abort(spidev->spi);
#endif
mutex_unlock(&device_list_lock);
return 0;
}
static void init_p_buf_cut(struct spidev_data *spidev)
{
int i = 0;
int j = 0;
spidev->buf_cut->recv_num = spidev->send_data_len / DMAC_ONE_TR_NUM;
spidev->buf_cut->last_buf_len = spidev->send_data_len % DMAC_ONE_TR_NUM;
printk("buf_cut recv_num:%d last_buf_len:%d\r\n",spidev->buf_cut->recv_num,spidev->buf_cut->last_buf_len);
for (i = 0; i < DMA_RECV_MAX_NUM; i++)
{
for (j = 0; j < DMAC_CNLL_MAX_NUM; j++)
{
spidev->buf_cut->pr_buf_fpga[i][j] = spidev->rxbuf.p_adr + (i*DMAC_MAX_TRF_SIZE) + (j*DMAC_ONE_TR_NUM);
}
printk("p_rx buf[%d] dma[%3d] padd:0x%x\r\n", i,j,spidev->buf_cut->pr_buf_fpga[i][0]);
}
}
static int fsfpgain_mmap(struct file *filp, struct vm_area_struct *vma)
{
int ret = 0;
struct spidev_data *spidev;
spidev = filp->private_data;
printk("fsfpgain:spidev addr0x%x-%x;spi addr0x%x-%x\r\n",*spidev,spidev,*spidev->spi,spidev->spi);
#ifdef _DEBUG
printk("fsfpgain_mmap run,PAGE_SIZE:%ld\r\n",PAGE_SIZE);
printk("vm_start:%lx vm_end:%lx\r\n", vma->vm_start,vma->vm_end);
#endif
//dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, void *cpu_addr,
// dma_addr_t dma_addr, size_t size, unsigned long attrs)
ret = dma_mmap_coherent(&spidev->spi->dev, vma, (void*)spidev->rxbuf.v_adr, spidev->rxbuf.p_adr,DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM);
memset(spidev->rxbuf.v_adr, 0,DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM);
#ifdef _DEBUG
memcpy(spidev->rxbuf.v_adr, "Hello,mmap!", sizeof("Hello,mmap!"));//test mmap
printk("fsfpgain_mmap re:%d-%s\r\n",ret,spidev->rxbuf.v_adr);
#endif
memset(spidev->rxbuf.v_adr, 0,DMAC_MAX_TRF_SIZE*DMA_RECV_MAX_NUM);
return ret;
}
static const struct file_operations spidev_fops = {
.owner = THIS_MODULE,
/* REVISIT switch to aio primitives, so that userspace
* gets more complete API coverage. It'll simplify things
* too, except for the locking.
*/
.write = spidev_write,
.read = spidev_read,
.unlocked_ioctl = spidev_ioctl,
.compat_ioctl = spidev_compat_ioctl,
.open = spidev_open,
.release = spidev_release,
.llseek = no_llseek,
.mmap = fsfpgain_mmap,
};
/*-------------------------------------------------------------------------*/
/* The main reason to have this class is to make mdev/udev create the
* /dev/spidevB.C character device nodes exposing our userspace API.
* It also simplifies memory management.
*/
static struct class *spidev_class;
#ifdef CONFIG_OF
static const struct of_device_id spidev_dt_ids[] = {
{ .compatible = "fsml,fsfpgain" },
{},
};
MODULE_DEVICE_TABLE(of, spidev_dt_ids);
#endif
#ifdef CONFIG_ACPI
/* Dummy SPI devices not to be used in production systems */
#define SPIDEV_ACPI_DUMMY 1
static const struct acpi_device_id spidev_acpi_ids[] = {
/*
* The ACPI SPT000* devices are only meant for development and
* testing. Systems used in production should have a proper ACPI
* description of the connected peripheral and they should also use
* a proper driver instead of poking directly to the SPI bus.
*/
{ "SPT0001", SPIDEV_ACPI_DUMMY },
{ "SPT0002", SPIDEV_ACPI_DUMMY },
{ "SPT0003", SPIDEV_ACPI_DUMMY },
{},
};
MODULE_DEVICE_TABLE(acpi, spidev_acpi_ids);
static void spidev_probe_acpi(struct spi_device *spi)
{
const struct acpi_device_id *id;
if (!has_acpi_companion(&spi->dev))
return;
id = acpi_match_device(spidev_acpi_ids, &spi->dev);
if (WARN_ON(!id))
return;
if (id->driver_data == SPIDEV_ACPI_DUMMY)
dev_warn(&spi->dev, "do not use this driver in production systems!\n");
}
#else
static inline void spidev_probe_acpi(struct spi_device *spi) {}
#endif
/*-------------------------------------------------------------------------*/
static int spidev_probe(struct spi_device *spi)
{
struct spidev_data *spidev;
int status;
unsigned long minor;
/*
* spidev should never be referenced in DT without a specific
* compatible string, it is a Linux implementation thing
* rather than a description of the hardware.
*/
WARN(spi->dev.of_node &&
of_device_is_compatible(spi->dev.of_node, "fsfpgain"),
"%pOF: buggy DT: spidev listed directly in DT\n", spi->dev.of_node);
spidev_probe_acpi(spi);
/* Allocate driver data */
spidev = kzalloc(sizeof(*spidev), GFP_KERNEL);
if (!spidev)
return -ENOMEM;
/* Initialize the driver data */
spidev->spi = spi;
printk("fsfpgain:spidev addr0x%x-%x;spi addr0x%x-%x\r\n",*spidev,spidev,*spi,spi);
spin_lock_init(&spidev->spi_lock);
mutex_init(&spidev->buf_lock);
//sema_init(&spidev->spi_sema,0);//初始化信号量
INIT_LIST_HEAD(&spidev->device_entry);
/* If we can allocate a minor number, hook up this device.
* Reusing minors is fine so long as udev or mdev is working.
*/
mutex_lock(&device_list_lock);
minor = find_first_zero_bit(minors, N_SPI_MINORS);
if (minor < N_SPI_MINORS) {
struct device *dev;
spidev->devt = MKDEV(SPIDEV_MAJOR, minor);
dev = device_create(spidev_class, &spi->dev, spidev->devt,
spidev, "fsfpgain");
status = PTR_ERR_OR_ZERO(dev);
} else {
dev_dbg(&spi->dev, "no minor number available!\n");
status = -ENODEV;
}
if (status == 0) {
set_bit(minor, minors);
list_add(&spidev->device_entry, &device_list);
}
mutex_unlock(&device_list_lock);
//spidev->speed_hz = spi->max_speed_hz;
setSpidev_data(spidev);
if (status == 0)
spi_set_drvdata(spi, spidev);//spidev private reg
else
kfree(spidev);
return status;
}
static int spidev_remove(struct spi_device *spi)
{
struct spidev_data *spidev = spi_get_drvdata(spi);
/* prevent new opens */
mutex_lock(&device_list_lock);
/* make sure ops on existing fds can abort cleanly */
spin_lock_irq(&spidev->spi_lock);
spidev->spi = NULL;
spin_unlock_irq(&spidev->spi_lock);
list_del(&spidev->device_entry);
device_destroy(spidev_class, spidev->devt);
clear_bit(MINOR(spidev->devt), minors);
resetSpidev_data(spidev);
if (spidev->users == 0)
kfree(spidev);
mutex_unlock(&device_list_lock);
return 0;
}
static struct spi_driver spidev_spi_driver = {
.driver = {
.name = "fsfpgain",
.of_match_table = of_match_ptr(spidev_dt_ids),
.acpi_match_table = ACPI_PTR(spidev_acpi_ids),
},
.probe = spidev_probe,
.remove = spidev_remove,
/* NOTE: suspend/resume methods are not necessary here.
* We don't do anything except pass the requests to/from
* the underlying controller. The refrigerator handles
* most issues; the controller driver handles the rest.
*/
};
/*-------------------------------------------------------------------------*/
static int __init spidev_init(void)
{
int status;
/* Claim our 256 reserved device numbers. Then register a class
* that will key udev/mdev to add/remove /dev nodes. Last, register
* the driver which manages those device numbers.
*/
BUILD_BUG_ON(N_SPI_MINORS > 256);
status = register_chrdev(SPIDEV_MAJOR, "spi", &spidev_fops);
if (status < 0)
return status;
spidev_class = class_create(THIS_MODULE, "fsfpgain");
if (IS_ERR(spidev_class)) {
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
return PTR_ERR(spidev_class);
}
status = spi_register_driver(&spidev_spi_driver);
if (status < 0) {
class_destroy(spidev_class);
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
}
return status;
}
module_init(spidev_init);
static void __exit spidev_exit(void)
{
spi_unregister_driver(&spidev_spi_driver);
class_destroy(spidev_class);
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
}
module_exit(spidev_exit);
MODULE_AUTHOR("shi guojie");
MODULE_DESCRIPTION("fsml");
MODULE_LICENSE("GPL");
MODULE_ALIAS("v1.0.0.0");
test_spidev.c
#include <stdio.h>
#include <ctype.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define DEVICE_NAME "/dev/fsfpgain"
#define HEAD_LEN 5
#define PKT_MAX_LEN 0x40
#define STATUS_LEN 0x01
#define SUNXI_OP_WRITE 0x01
#define SUNXI_OP_READ 0x03
#define STATUS_WRITABLE 0x02
#define STATUS_READABLE 0x04
#define WRITE_DELAY 200
#define READ_DELAY 100000
void dump_data(unsigned char *buf, unsigned int len)
{
unsigned int i;
unsigned char tmp[len*2], cnt = 0;
for (i = 0; i < len; i++) {
if (i%0x10== 0)
cnt += sprintf(tmp + cnt, "0x%08x: ", i);
cnt += sprintf(tmp + cnt, "%02x ", buf[i]);
if ( (i%0x10== 0x0f) || (i == (len -1)) ) {
printf("%s\n", tmp);
cnt = 0;
}
}
}
void batch_rand(char *buf, unsigned int length)
{
unsigned int i;
srand(time(0));
for(i = 0; i < length; i++) {
*(buf + i) = rand() % 256;
}
}
int main(int argc, const char *argv[])
{
unsigned int length = 0, test_len;
char wbuf_head[HEAD_LEN] = {SUNXI_OP_WRITE, 0x0b, 0xb0, 0xea, 0x10};
char rbuf_head[HEAD_LEN] = {SUNXI_OP_READ, 0x00, 0x00, 0xc0, 0x00};
char wbuf[PKT_MAX_LEN], rbuf[PKT_MAX_LEN], i, time;
int fd, ret;
test_len = 10;//send 10 numbers
if (test_len > PKT_MAX_LEN) {
printf("invalid argument, numbers must less 64B\n");
return -1;
}
wbuf_head[4] = test_len;
rbuf_head[4] = test_len;
for (i = 0; i < test_len; i++)
wbuf[i] = i;
printf("wbuf:\n");
dump_data(wbuf, test_len);
fd = open(DEVICE_NAME, O_RDWR);
if (fd <= 0) {
printf("Fail to to open %s\n", DEVICE_NAME);
ret = -1;
return ret;
}
char str[100];
memset(str,0,100);
int size = 1000;
char* buffer = (char*)malloc(size * sizeof(char));
char ch = 'a';
for (int i = 0; i < size; i++) {
buffer[i] = ch;
ch++;
if (ch > 'z') {
ch = 'a';
}
}
sprintf(str,"abcdefghijklmnabcdefghijklmnabcdefghijklmnabcdefghijklmnabcdefghijklmnabcdefghijklmnabcdefghijklmn");
//for(int x=0;x<10;x++)
for(int x=0;x<10;x++)
{
write(fd, buffer, size);
}
if(0)
{//write
if (write(fd, wbuf_head, HEAD_LEN) != HEAD_LEN) {
printf("W Fail to write head\n");
ret = -1;
goto err;
} else
printf("W write head successful\n");
usleep(WRITE_DELAY);
if (write(fd, wbuf, test_len) != test_len) {
printf("W Fail to write data\n");
ret = -1;
goto err;
} else
printf("W write data successful\n");
usleep(READ_DELAY);
}
err:
if (fd > 0)
close(fd);
return ret;
}
test_fsfpgain.c
#include <stdio.h>
#include <ctype.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/mman.h>
#include <string.h>
#define DMAC_CNLL_MAX_NUM 32
#define DMAC_ONE_TR_NUM 1000
#define DMAC_MAX_TRF_SIZE DMAC_CNLL_MAX_NUM*DMAC_ONE_TR_NUM
#define DMA_RECV_MAX_NUM 10//环形缓冲器大小
int main()
{
int ret,fpdata,fpio,i,shmm_len,one_trf_len;
long value;
void* shmm_buf = NULL;
char* trf_buf[DMAC_CNLL_MAX_NUM];
char rbuf[1];
char cstr[100] = "hello!spi world!";
fpdata = open("/dev/fsfpgain", O_RDWR);
if(0 > fpdata)
{
printf("open error!\r\n");
return -1;
}
ret = ioctl(fpdata, 0x100, value);
printf("100fsfpga version = 0x%x\r\n", ret);
sleep(1);
value = 10240;
ret = ioctl(fpdata, 0x302, value);
printf("302fsfpga set send-data-len = %d\r\n", ret);
sleep(1);
ret = ioctl(fpdata, 0x305, value);
printf("0x305fsfpga get send-data-len = %d\r\n", ret);
sleep(1);
shmm_len = ioctl(fpdata, 0x307, value);
printf("0x307shmm len = %d\r\n",shmm_len);
sleep(1);
one_trf_len = ioctl(fpdata, 0x306, value);
printf("0x306one dmaspi len = %d\r\n",one_trf_len);
sleep(1);
printf("&shmm_buf:0x%p shmm_buf:0x%p shmm_len:%d\r\n",&shmm_buf, shmm_buf,shmm_len);
shmm_buf = mmap(NULL, shmm_len, PROT_READ|PROT_WRITE,MAP_SHARED, fpdata,0);
if(MAP_FAILED == shmm_buf)
{
printf("mmap error!\r\n");
return 1;
}
printf("&shmm_buf:0x%p shmm_buf:0x%p shmm_len:%d\r\n",&shmm_buf, shmm_buf,shmm_len);
printf("shmm_buf:%s\r\n",(char*)shmm_buf);
sleep(1);
ret = ioctl(fpdata, 0x303, value);
printf("fsfpga start work = %d\r\n", ret);
printf("sleep...\r\n");
sleep(1);
for(i = 0; i < DMA_RECV_MAX_NUM; i++)
{
trf_buf[i] = (char*)shmm_buf + (i * one_trf_len);
printf("trf_buf[%d]add:0x%lx\r\n",i,(long)trf_buf[i]);
}
printf("trf_buf[0]:%s\r\n", trf_buf[0]);
printf("set trf_buf ok\r\n");
sleep(1);
while (1)
{
//memset(shmm_buf, 0 ,shmm_len);
ret = ioctl(fpdata, 0x301, value);
printf("ioctl 0x301 ret:0x%x-v:0x%lx\r\n",ret, value);
printf("get data no = %x\r\n",ret);
value = 1;
break;
usleep(500*1000);
}
printf("munmap return:%d\r\n",munmap(shmm_buf, shmm_len));
close(fpdata);
return 0;
}
4.运行故障提示
# ./test_fafpgain
[ 4610.396357] fsfpgain:spidev_ioctl is run:0x100-0xb6ee3b58
[ 4610.402515] fsfpgain:spidev addr0x9900000-650065;spi addr0xc6594000-bf002018
[ 4610.410667] 2121wzg cmd 0x100 arg:-1225901224 ret:536871187 DMAC_MAX_TRF_SIZE:32000
100fsfpga version = 0x20000113
[ 4611.420340] fsfpgain:spidev_ioctl is run:0x302-0x2800
[ 4611.426075] fsfpgain:spidev addr0x9900000-660066;spi addr0xc6594000-bf002018
[ 4611.434057] buf_cut recv_num:10 last_buf_len:240
[ 4611.439322] p_rx buf[0] dma[ 32] padd:0x47880000
[ 4611.444561] p_rx buf[1] dma[ 32] padd:0x47887d00
[ 4611.449983] p_rx buf[2] dma[ 32] padd:0x4788fa00
[ 4611.455215] p_rx buf[3] dma[ 32] padd:0x47897700
[ 4611.460490] p_rx buf[4] dma[ 32] padd:0x4789f400
[ 4611.465722] p_rx buf[5] dma[ 32] padd:0x478a7100
[ 4611.470986] p_rx buf[6] dma[ 32] padd:0x478aee00
[ 4611.476223] p_rx buf[7] dma[ 32] padd:0x478b6b00
[ 4611.481478] p_rx buf[8] dma[ 32] padd:0x478be800
[ 4611.486730] p_rx buf[9] dma[ 32] padd:0x478c6500
[ 4611.491998] 2121wzg cmd 0x302 arg:10240 ret:10240 DMAC_MAX_TRF_SIZE:32000
302fsfpga set send-data-len = 10240
[ 4612.500269] fsfpgain:spidev_ioctl is run:0x305-0x2800
[ 4612.506000] fsfpgain:spidev addr0x9900000-670067;spi addr0xc6594000-bf002018
[ 4612.513984] 2121wzg cmd 0x305 arg:10240 ret:10240 DMAC_MAX_TRF_SIZE:32000
0x305fsfpga get send-data-len = 10240
[ 4613.522220] fsfpgain:spidev_ioctl is run:0x307-0x2800
[ 4613.528134] fsfpgain:spidev addr0x9900000-680068;spi addr0xc6594000-bf002018
[ 4613.536077] 2121wzg cmd 0x307 arg:10240 ret:320000 DMAC_MAX_TRF_SIZE:32000
0x307shmm len = 320000
[ 4614.544450] fsfpgain:spidev_ioctl is run:0x306-0x2800
[ 4614.550210] fsfpgain:spidev addr0x9900000-690069;spi addr0xc6594000-bf002018
[ 4614.558175] 2121wzg cmd 0x306 arg:10240 ret:32000 DMAC_MAX_TRF_SIZE:32000
0x306one dmaspi len = 32000
[ 4615.566559] fsfpgain:spidev addr0x9900000-6a006a;spi addr0xc6594000-bf002018
&shmm_buf:0x0xbe84bca4 shmm_buf:0x0xb6da9000 shmm_len:320000
shmm_buf:
[ 4616.579679] fsfpgain:spidev_ioctl is run:0x303-0x2800
[ 4616.585411] fsfpgain:spidev addr0x9900000-6a006a;spi addr0xc6594000-bf002018
[ 4616.593411] fafpgain start work!
[ 4616.597144] 2121wzg cmd 0x303 arg:10240 ret:1 DMAC_MAX_TRF_SIZE:32000
fsfpga start work = 1
sleep...
[ 4616.607572] fsfpgain:irq_gpio rec buf[0],add:47880000
[ 4616.613588] fafpgain:spi_fpga_recv 10-240
[ 4616.613593] fsfpgain:transfer len-1000 speed-10000000
[ 4616.623825] fsfpgain spi1.0: Bufferless transfer has length 1000
[ 4616.630553] fsfpgain: spidev_sync re-0
[ 4616.634722] fsfpgain: spidev_sync 10000000-0-1000
//fsfpgain spi1.0: Bufferless transfer has length 1000是spi.c中的报错，我没有理解为什么会跳到这里面来。使用test_spidev.c来测试，就不会跳进来，在驱动层面都是调用的write函数来读写的。
5.问题汇总：
1）通过GPIO中断来调用spi读写函数，spi不能正常工作，只有片选，没有时钟：
2）如何设置缓存，使得spi可以连续读取大数据量，目前片选频繁跳动，效率太低，25Hz的中断没办法完成数据读取。