s5pv210与stm32 spi通信

た入场券 2022-09-17 12:15 179阅读 0赞

spi通信不支持从设备主动给主设备发送数据，所以我把spi的用户空间驱动改了一下，实现过程是这样的，用一个中断来响应从设备的要求，即当STM32要主动给主设备发送数据的时候，将中断脚拉低，用户空间检测到中断后，主动给STM32发送一个空数据，这样spi就能读到STM32所要发送的数据了。SPI通信发数据与接数据是同时进行的，这个大家可以看下SPI协议。

以下我我修改的用户空间的驱动:

/*
     * spidev.c -- simple synchronous userspace interface to SPI devices
     *
     * Copyright (C) 2006 SWAPP
     *	Andrea Paterniani <a.paterniani@swapp-eng.it>
     * Copyright (C) 2007 David Brownell (simplification, cleanup)
     *
     * 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.
     *
     * This program is distributed in the hope that 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., 675 Mass Ave, Cambridge, MA 02139, USA.
     */
    
    #include <linux/init.h>
    #include <linux/module.h>
    #include <linux/ioctl.h>
    #include <linux/fs.h>
    #include <linux/device.h>
    #include <linux/err.h>
    #include <linux/list.h>
    #include <linux/errno.h>
    #include <linux/mutex.h>
    #include <linux/slab.h>
    
    #include <linux/irq.h>
    #include <linux/interrupt.h>
    #include <mach/gpio.h>
    #include <plat/gpio-cfg.h>
    #include <mach/regs-gpio.h>
    #include <linux/delay.h>
    
    #include <linux/spi/spi.h>
    #include <linux/spi/spidev_gzsd.h>
    
    #include <asm/uaccess.h>
    
    #include <linux/poll.h>
    
    #define	SPI_IRQ			IRQ_EINT(2)
    #define	IRQSTATE		S5PV210_GPH0(2)
    #define BUF_SIZE		38
    u8 gzsd_buffer[BUF_SIZE];
    struct spi_transfer	*gk_xfers;
    struct spi_ioc_transfer	*g_uxfers;
    /*
     * This supports acccess 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)
    
    struct spidev_data {
    	dev_t			devt;
    	spinlock_t		spi_lock;
    	struct spi_device	*spi;
    	struct list_head	device_entry;
    
    	/* buffer is NULL unless this device is open (users > 0) */
    	struct mutex		buf_lock;
    	unsigned		users;
    	u8			*buffer;
    	int irq;
    //add by dao
    	wait_queue_head_t rqueue;
    };
    
    static flag_poll = 0;
    static LIST_HEAD(device_list);
    static DEFINE_MUTEX(device_list_lock);
    
    static unsigned bufsiz = 4096;
    module_param(bufsiz, uint, S_IRUGO);
    MODULE_PARM_DESC(bufsiz, "data bytes in biggest supported SPI message");
    
    /*-------------------------------------------------------------------------*/
    
    /*
     * We can't use the standard synchronous wrappers for file I/O; we
     * need to protect against async removal of the underlying spi_device.
     */
    static void spidev_complete(void *arg)
    {
    	complete(arg);
    }
    
    static ssize_t
    spidev_sync(struct spidev_data *spidev, struct spi_message *message)
    {
    	DECLARE_COMPLETION_ONSTACK(done);
    	int status;
    
    	message->complete = spidev_complete;
    	message->context = &done;
    	spin_lock_irq(&spidev->spi_lock);
    	if (spidev->spi == NULL)
    		status = -ESHUTDOWN;
    	else
    		status = spi_async(spidev->spi, message);
    	spin_unlock_irq(&spidev->spi_lock);
    
    	if (status == 0) {
    		wait_for_completion(&done);
    		status = message->status;
    		if (status == 0)
    			status = message->actual_length;
    	}
    	return status;
    }
    
    static inline ssize_t
    spidev_sync_write(struct spidev_data *spidev, size_t len)
    {
    	struct spi_transfer	t = {
    			.tx_buf		= spidev->buffer,
    			.len		= len,
    		};
    	struct spi_message	m;
    
    	spi_message_init(&m);
    	spi_message_add_tail(&t, &m);
    	return spidev_sync(spidev, &m);
    }
    
    static inline ssize_t
    spidev_sync_read(struct spidev_data *spidev, size_t len)
    {
    	struct spi_transfer	t = {
    			.rx_buf		= spidev->buffer,
    			.len		= len,
    		};
    	struct spi_message	m;
    	spi_message_init(&m);
    	spi_message_add_tail(&t, &m);
    	return spidev_sync(spidev, &m);
    }
    
    /*-------------------------------------------------------------------------*/
    
    /* 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->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)
    {
    	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);
    	missing = copy_from_user(spidev->buffer, buf, count);
    	if (missing == 0) {
    		status = spidev_sync_write(spidev, count);
    	} else
    		status = -EFAULT;
    	mutex_unlock(&spidev->buf_lock);
    
    	return status;
    }
    
    static int spidev_message(struct spidev_data *spidev,
    		struct spi_ioc_transfer *u_xfers, unsigned n_xfers)
    {
    	struct spi_message	msg;
    	struct spi_transfer	*k_xfers;
    	struct spi_transfer	*k_tmp;
    	struct spi_ioc_transfer *u_tmp;
    	unsigned		n, total;
    	u8			*buf;
    	int			status = -EFAULT;
    	spi_message_init(&msg);
    	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.
    	 */
    	buf = spidev->buffer;
    	total = 0;
    	for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
    			n;
    			n--, k_tmp++, u_tmp++) {
    		k_tmp->len = u_tmp->len;
    		total += k_tmp->len;
    		if (total > bufsiz) {
    			status = -EMSGSIZE;
    			goto done;
    		}
    		if (u_tmp->rx_buf) {
    			k_tmp->rx_buf = buf;
    			if (!access_ok(VERIFY_WRITE, (u8 __user *)
    						(uintptr_t) u_tmp->rx_buf,
    						u_tmp->len))
    				goto done;
    		}
    		if (u_tmp->tx_buf) {
    			k_tmp->tx_buf = buf;
    			if (copy_from_user(buf, (const u8 __user *)
    						(uintptr_t) u_tmp->tx_buf,
    					u_tmp->len))
    				goto done;
    		}
    
    		buf += k_tmp->len;
    
    		k_tmp->cs_change = !!u_tmp->cs_change;
    		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;
    #ifdef VERBOSE
    		dev_dbg(&spidev->spi->dev,
    			"  xfer len %zd %s%s%s%dbits %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->speed_hz ? : spidev->spi->max_speed_hz);
    #endif
    		spi_message_add_tail(k_tmp, &msg);
    	}
    	printk("%s :----line is %d\n",__func__,__LINE__);
    	status = spidev_sync(spidev, &msg);
    	printk("%s :----line is %d\n",__func__,__LINE__);
    	if (status < 0)
    		goto done;
    	/* copy any rx data out of bounce buffer */
    	buf = spidev->buffer;
    	for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) {
    		if (u_tmp->rx_buf) {
    			if (__copy_to_user((u8 __user *)
    					(uintptr_t) u_tmp->rx_buf, buf,
    					u_tmp->len)) {
    				status = -EFAULT;
    				goto done;
    			}
    		}
    		buf += u_tmp->len;
    	}
    	status = total;
    
    done:
    	kfree(k_xfers);
    	return status;
    }
    
    static DECLARE_WAIT_QUEUE_HEAD(gzsd_spi_wait);
    
    static irqreturn_t gzsd_spiread(int irq, void *dev_id)
    {
    	struct spidev_data *spidev = (struct spidev_data *)dev_id;
    
    	//dev_err(&spidev->spi->dev, "is spi dev now.\n");
    	disable_irq_nosync(irq);
    	flag_poll = 1;
    	//printk("%s:------------line is %d\n",__func__,__LINE__);
    #if	1
    	wake_up_interruptible(&spidev->rqueue);
    #else
    	wake_up(&gzsd_spi_wait);
    #endif
    	//wake_up_interruptible_sync(&spidev->rqueue);
    	//wake_up(&spidev->rqueue);
    	enable_irq(irq);
    	return IRQ_HANDLED;
    }
    
    unsigned int gzsd_poll(struct file *filp, poll_table *wait)
    {
    	struct spidev_data	*spidev;
    	spidev = filp->private_data;
    	unsigned int mask = 0;
    	//printk("%s:------------line is %d\n",__func__,__LINE__);
    #if	1
    	poll_wait(filp, &spidev->rqueue, wait);
    #else
    	poll_wait(filp, &gzsd_spi_wait, wait);
    #endif
    	if(flag_poll) {
    		mask = POLLIN | POLLRDNORM; //can be read
    		flag_poll = 0;
    	}
    	return mask;
    }
    
    static long
    spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
    {
    	int			err = 0;
    	int			retval = 0;
    	struct spidev_data	*spidev;
    	struct spi_device	*spi;
    	u32			tmp;
    	unsigned		n_ioc;
    	struct spi_ioc_transfer	*ioc;
    
    	/* Check type and command number */
    	if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC)
    		return -ENOTTY;
    
    	/* Check access direction once here; don't repeat below.
    	 * IOC_DIR is from the user perspective, while access_ok is
    	 * from the kernel perspective; so they look reversed.
    	 */
    	if (_IOC_DIR(cmd) & _IOC_READ)
    		err = !access_ok(VERIFY_WRITE,
    				(void __user *)arg, _IOC_SIZE(cmd));
    	if (err == 0 && _IOC_DIR(cmd) & _IOC_WRITE)
    		err = !access_ok(VERIFY_READ,
    				(void __user *)arg, _IOC_SIZE(cmd));
    	if (err)
    		return -EFAULT;
    
    	/* guard against device removal before, or while,
    	 * we issue this ioctl.
    	 */
    	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;
    
    	/* 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) {
    	/* read requests */
    	case SPI_IOC_RD_MODE:
    		retval = __put_user(spi->mode & SPI_MODE_MASK,
    					(__u8 __user *)arg);
    		break;
    	case SPI_IOC_RD_LSB_FIRST:
    		retval = __put_user((spi->mode & SPI_LSB_FIRST) ?  1 : 0,
    					(__u8 __user *)arg);
    		break;
    	case SPI_IOC_RD_BITS_PER_WORD:
    		retval = __put_user(spi->bits_per_word, (__u8 __user *)arg);
    		break;
    	case SPI_IOC_RD_MAX_SPEED_HZ:
    		retval = __put_user(spi->max_speed_hz, (__u32 __user *)arg);
    		break;
    
    	/* write requests */
    	case SPI_IOC_WR_MODE:
    		retval = __get_user(tmp, (u8 __user *)arg);
    		if (retval == 0) {
    			u8	save = spi->mode;
    
    			if (tmp & ~SPI_MODE_MASK) {
    				retval = -EINVAL;
    				break;
    			}
    
    			tmp |= spi->mode & ~SPI_MODE_MASK;
    			spi->mode = (u8)tmp;
    			retval = spi_setup(spi);
    			if (retval < 0)
    				spi->mode = save;
    			else
    				dev_dbg(&spi->dev, "spi mode %02x\n", tmp);
    		}
    		break;
    	case SPI_IOC_WR_LSB_FIRST:
    		retval = __get_user(tmp, (__u8 __user *)arg);
    		if (retval == 0) {
    			u8	save = spi->mode;
    
    			if (tmp)
    				spi->mode |= SPI_LSB_FIRST;
    			else
    				spi->mode &= ~SPI_LSB_FIRST;
    			retval = spi_setup(spi);
    			if (retval < 0)
    				spi->mode = save;
    			else
    				dev_dbg(&spi->dev, "%csb first\n",
    						tmp ? 'l' : 'm');
    		}
    		break;
    	case SPI_IOC_WR_BITS_PER_WORD:
    		retval = __get_user(tmp, (__u8 __user *)arg);
    		if (retval == 0) {
    			u8	save = spi->bits_per_word;
    
    			spi->bits_per_word = tmp;
    			retval = spi_setup(spi);
    			if (retval < 0)
    				spi->bits_per_word = save;
    			else
    				dev_dbg(&spi->dev, "%d bits per word\n", tmp);
    		}
    		break;
    	case SPI_IOC_WR_MAX_SPEED_HZ:
    		retval = __get_user(tmp, (__u32 __user *)arg);
    		if (retval == 0) {
    			u32	save = spi->max_speed_hz;
    
    			spi->max_speed_hz = tmp;
    			retval = spi_setup(spi);
    			if (retval < 0)
    				spi->max_speed_hz = save;
    			else
    				dev_dbg(&spi->dev, "%d Hz (max)\n", tmp);
    		}
    		break;
    
    	default:
    		/* segmented and/or full-duplex I/O request */
    		if (_IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
    				|| _IOC_DIR(cmd) != _IOC_WRITE) {
    			retval = -ENOTTY;
    			break;
    		}
    
    		tmp = _IOC_SIZE(cmd);
    		if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) {
    			retval = -EINVAL;
    			break;
    		}
    
    		n_ioc = tmp / sizeof(struct spi_ioc_transfer);
    
    		if (n_ioc == 0)
    			break;
    
    		g_uxfers = kmalloc(tmp, GFP_KERNEL);
    		if (!g_uxfers) {
    			printk("g_uxfers alloc failed\n");
    		}
    		if (__copy_from_user(g_uxfers, (void __user *)arg, tmp)) {
    			kfree(g_uxfers);
    			printk("g_uxfers copy failed\n");
    		}
    
    		/* copy into scratch area */
    		ioc = kmalloc(tmp, GFP_KERNEL);
    		if (!ioc) {
    			retval = -ENOMEM;
    			break;
    		}
    
    		if (__copy_from_user(ioc, (void __user *)arg, tmp)) {
    			kfree(ioc);
    			retval = -EFAULT;
    			break;
    		}
    
    		/* translate to spi_message, execute */
    		retval = spidev_message(spidev, ioc, n_ioc);
    		kfree(ioc);
    		break;
    	}
    
    	mutex_unlock(&spidev->buf_lock);
    	spi_dev_put(spi);
    	return retval;
    }
    
    static int spidev_open(struct inode *inode, struct file *filp)
    {
    	struct spidev_data	*spidev;
    	int			status = -ENXIO;
    
    	mutex_lock(&device_list_lock);
    	
    	gk_xfers = kcalloc(1, sizeof (*gk_xfers), GFP_KERNEL);
    	if (gk_xfers == NULL)
    		printk("alloc gk_xfers_failed\n");
    
    	list_for_each_entry(spidev, &device_list, device_entry) {
    		if (spidev->devt == inode->i_rdev) {
    			status = 0;
    			break;
    		}
    	}
    	if (status == 0) {
    		if (!spidev->buffer) {
    			spidev->buffer = kmalloc(bufsiz, GFP_KERNEL);
    			if (!spidev->buffer) {
    				dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
    				status = -ENOMEM;
    			}
    		}
    		if (status == 0) {
    			spidev->users++;
    			filp->private_data = spidev;
    			nonseekable_open(inode, filp);
    		}
    	} else
    		pr_debug("spidev: nothing for minor %d\n", iminor(inode));
    	mutex_unlock(&device_list_lock);
    	return status;
    }
    
    static int spidev_release(struct inode *inode, struct file *filp)
    {
    	struct spidev_data	*spidev;
    	int			status = 0;
    
    	mutex_lock(&device_list_lock);
    	spidev = filp->private_data;
    	filp->private_data = NULL;
    
    	/* last close? */
    	spidev->users--;
    	if (!spidev->users) {
    		int		dofree;
    
    		kfree(spidev->buffer);
    		spidev->buffer = NULL;
    
    		/* ... after we unbound from the underlying device? */
    		spin_lock_irq(&spidev->spi_lock);
    		dofree = (spidev->spi == NULL);
    		spin_unlock_irq(&spidev->spi_lock);
    
    		if (dofree)
    			kfree(spidev);
    	}
    	//disable_irq_nosync(spidev->irq);
    	kfree(gk_xfers);
    	kfree(g_uxfers);
    	mutex_unlock(&device_list_lock);
    
    	return status;
    }
    
    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,
    	.open =		spidev_open,
    	.release =	spidev_release,
    	.poll		=gzsd_poll,
    };
    
    /*-------------------------------------------------------------------------*/
    
    /* 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;
    
    /*-------------------------------------------------------------------------*/
    
    static int __devinit spidev_probe(struct spi_device *spi)
    {
    	struct spidev_data	*spidev;
    	int			status;
    	unsigned long		minor;
    	int err;
    	/* Allocate driver data */
    	spidev = kzalloc(sizeof(*spidev), GFP_KERNEL);
    	if (!spidev)
    		return -ENOMEM;
    
    	/* Initialize the driver data */
    	spidev->spi = spi;
    	spin_lock_init(&spidev->spi_lock);
    	mutex_init(&spidev->buf_lock);
    
    	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, "spidev%d.%d",
    				    spi->master->bus_num, spi->chip_select);
    		status = IS_ERR(dev) ? PTR_ERR(dev) : 0;
    	} 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);
    	}
    
    	spidev->irq = SPI_IRQ;
    
    	err = request_irq(spidev->irq, gzsd_spiread, IRQ_TYPE_EDGE_FALLING,"spi", spidev);
    	if(err < 0) {
    		dev_err(&spidev->spi->dev, "Unable to request spi IRQ.\n");
    	}
    
    	init_waitqueue_head(&spidev->rqueue);
    
    	mutex_unlock(&device_list_lock);
    
    	if (status == 0)
    		spi_set_drvdata(spi, spidev);
    	else
    		kfree(spidev);
    
    	return status;
    }
    
    static int __devexit spidev_remove(struct spi_device *spi)
    {
    	struct spidev_data	*spidev = spi_get_drvdata(spi);
    
    	/* make sure ops on existing fds can abort cleanly */
    	spin_lock_irq(&spidev->spi_lock);
    	spidev->spi = NULL;
    	spi_set_drvdata(spi, NULL);
    	spin_unlock_irq(&spidev->spi_lock);
    
    	/* prevent new opens */
    	mutex_lock(&device_list_lock);
    	list_del(&spidev->device_entry);
    	device_destroy(spidev_class, spidev->devt);
    	clear_bit(MINOR(spidev->devt), minors);
    	if (spidev->users == 0)
    		kfree(spidev);
    	mutex_unlock(&device_list_lock);
    
    	return 0;
    }
    
    static struct spi_driver spidev_spi_driver = {
    	.driver = {
    		.name =		"spidev",
    		.owner =	THIS_MODULE,
    	},
    	.probe =	spidev_probe,
    	.remove =	__devexit_p(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, "spidev");
    	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("Andrea Paterniani, <a.paterniani@swapp-eng.it>");
    MODULE_DESCRIPTION("User mode SPI device interface");
    MODULE_LICENSE("GPL");
    MODULE_ALIAS("spi:spidev");

文件名:spidev\_gzsd.c

位置: drivers/spi

将drivers/spi/Makefile里的spidev.c修改为spidev\_gzsd.c

210　spi测试程序如下:

/*
     * SPI testing utility (using spidev driver)
     *
     * Copyright (c) 2007  MontaVista Software, Inc.
     * Copyright (c) 2007  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.
     *
     * Cross-compile with cross-gcc -I/path/to/cross-kernel/include
     */
    
    #include <stdint.h>
    #include <unistd.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <getopt.h>
    #include <fcntl.h>
    #include <sys/ioctl.h>
    #include <linux/types.h>
    #include "spidev.h"
    //#include <termios.h>
    
    #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
    
    #define BUF_SIZE	38
    #define READ_SIZE	(BUF_SIZE + 1)
    
    static const char *device = "/dev/spidev0.0";
    static uint8_t mode;
    static uint8_t bits = 8;
    static uint32_t speed = 140000;//140000;
    static uint16_t delay;
    
    static void transfer(int fd)
    {
    	int ret;
    
    	uint8_t tx[] = {
    		0x01, 0xFD, 0xFC, 0xFB, 0xFA, 0xF9,
    		0xF8, 0xF7, 0xF6, 0xF5, 0xF4, 0xF3,
    		0xF2, 0xF1, 0xF0, 0xEF, 0xEE, 0xED,
    		0xEC, 0xEB, 0xEA, 0xE9, 0xE8, 0xE7,
    		0xE6, 0xE5, 0xE4, 0xE3, 0xE2, 0xE1,
    		0xE0, 0xDF, 0xDE, 0xDD, 0xDC, 0xDB,
    		0xDA, 0xD9,
    	};
    
    	uint8_t rx[ARRAY_SIZE(tx)] = {0, };
    	struct spi_ioc_transfer tr = {
    		.tx_buf = (unsigned long)tx,
    		.rx_buf = (unsigned long)rx,
    		.len = ARRAY_SIZE(tx),
    		.delay_usecs = delay,
    		.speed_hz = speed,
    		.bits_per_word = bits,
    	};
    	ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
    #if	1
    	if(rx[0] != 0xff)
    	{
    		for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {
    			if (!(ret % 6))
    				puts("");
    			printf("%.2d ", rx[ret]);
    		}
    		puts("");
    	}
    #endif
    }
    
    static void do_read(int fd, int len)
    {
    	uint8_t	buf[len], bp[len];
    	int		status;
    
    	/* read at least 2 bytes, no more than 32 */
    	if (len < 2)
    		len = 2;
    	else if (len > sizeof(buf))
    		len = sizeof(buf);
    	memset(buf, 0, sizeof buf);
    
    	status = read(fd, buf, len);
    	if (status < 0) {
    		printf("read error \n");
    		return;
    	}
    	if (status != len) {
    		fprintf(stderr, "short read\n");
    		return;
    	}
    #if	0
    	printf("read(%2d, %2d): %02x %02x,", len, status,
    		buf[0], buf[1]);
    	status -= 2;
    	bp = buf + 2;
    	while (status-- > 0)
    		printf(" %02x", *bp++);
    	printf("\n");
    #else
    	int i;
    #if	1
    	printf("do read data is :\n");
    	for(i = 0;i < len;i++)
    		printf("  %d",buf[i]);
    	printf("\n");
    #else
    	for(i = 0;i < (len - 1);i++)
    	{
    		bp[i] = buf[i+1];
    	}
    	bp[len-1] = buf[0];
    	printf("data is :\n");
    	for(i = 0;i < len;i++)
    		printf("  %d",bp[i]);
    	printf("\n");
    #endif
    #endif
    }
    
    static void do_write(int fd,int cmd)
    {
    	struct spi_ioc_transfer	xfer;
    	//unsigned char		buf[BUF_SIZE], *bp;
    	uint8_t			buf[BUF_SIZE], *bp;
    	int			status;
    	int			len;
    
    	uint8_t tx[] = {
    		cmd, (cmd +1), (cmd+2), 0xFB, 0xFA, 0xF9,
    		0xF8, 0xF7, 0xF6, 0xF5, 0xF4, 0xF3,
    		0xF2, 0xF1, 0xF0, 0xEF, 0xEE, 0xED,
    		0xEC, 0xEB, 0xEA, 0xE9, 0xE8, 0xE7,
    		0xE6, 0xE5, 0xE4, 0xE3, 0xE2, 0xE1,
    		0xE0, 0xDF, 0xDE, 0xDD, 0xDC, 0xDB,
    		0xDA, 0xD9,
    	};
    	//memset(xfer, 0, sizeof xfer);
    	memset(buf, 1, sizeof buf);
    
    	len = sizeof buf;
    	//buf[0] = cmd;
    #if	0
    	buf[0] = cmd;
    	buf[1] = cmd;
    
    	xfer.tx_buf = (unsigned long)buf;
    	xfer.len = len;
    
    	status = ioctl(fd, SPI_IOC_MESSAGE(1), xfer);
    	if (status < 0) {
    		printf("SPI_IOC_MESSAGE\n");
    		return;
    	}
    	//printf("do write data is %d\n",buf[0]);
    	printf("response(%2d, %2d)\n", len, status);
    #endif
    	status = write(fd,tx,BUF_SIZE);
    	if(status < 0)
    		printf("do write failed\n");
    #if	0
    	for (bp = buf; len; len--)
    		printf(" %02x", *bp++);
    	printf("\n");
    #endif
    
    }
    
    int main(int argc, char *argv[])
    {
    	int ret = 0;
    	int fd;
    	int data;
    	fd_set rds;    
    	struct timeval tv;
    #if	0
    	if(argc < 2) {
    		printf("please enter one parameter at least\n");
    		return 0;
    	}
    
    	data = atoi(argv[1]);
    #else
    	data = 0;
    #endif
    	fd = open(device, O_RDWR);
    	if (fd < 0)
    		printf("can't open device");
    
    	mode = SPI_MODE_1;
    	/*
    	 * spi mode
    	 */
    	ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
    	if (ret == -1)
    		printf("can't set spi mode");
    
    	ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
    	if (ret == -1)
    		printf("can't get spi mode");
    
    	/*
    	 * bits per word
    	 */
    	ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
    	if (ret == -1)
    		printf("can't set bits per word");
    
    	ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
    	if (ret == -1)
    		printf("can't get bits per word");
    
    	/*
    	 * max speed hz
    	 */
    	ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
    	if (ret == -1)
    		printf("can't set max speed hz");
    
    	ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
    	if (ret == -1)
    		printf("can't get max speed hz");
    
    	printf("spi mode: %d\n", mode);
    	printf("bits per word: %d\n", bits);
    	printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
    
    	//FD_ZERO(&rds);    
    	//FD_SET(fd, &rds);
    	//tv.tv_sec = 10;
    	//tv.tv_usec = 0;
    	int i;
    	while(1)
    	{
    		
    		FD_ZERO(&rds);    
    		FD_SET(fd, &rds);
    		tv.tv_sec = 1;
    		tv.tv_usec = 0;
    		printf("send daia is -----------------------%d\n",data);
    		do_write(fd,data);
    		sleep(1);	
    		ret = select(fd+1,&rds,NULL,NULL,&tv);
    		if(ret < 0) {
    			printf("select error!\n");
    			//break;
    		}
    		printf("ret is +++++++++++++++++++%d\n",ret);
    		if (FD_ISSET(fd, &rds))
    			do_read(fd,BUF_SIZE);
    		data++;
    		if(data > 8)
    			data = 0;
    		sleep(1);
    	}
    	close(fd);
    
    	return ret;
    }

这两部分源码下载地址为: [点击打开链接][Link 1]

STM32主函数代码:

#include "stm32f10x.h"
    #include "uart.h"
    #include "spi.h"
    
    
    void SPItest(void);
    void UARTtest(USART_TypeDef *port);
    extern void Uart_SendStringn(USART_TypeDef *port,char *pt,int n);
    extern  void Delay_ARMJISHU(__IO uint32_t nCount);
    
    void SPIsend_Init(void)
    {
    	GPIO_InitTypeDef  GPIO_InitStructure;
    //spi send interrupt control
    	RCC_APB2PeriphClockCmd (RCC_APB2Periph_GPIOC, ENABLE);//	使能PC,AFIO
    	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7; 
    	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; 
    	//GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //推挽输出 
    	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //
    	GPIO_Init(GPIOC, &GPIO_InitStructure); 
    //end
    }
    void send_onoff(int onoff)
    {
    	if(onoff)
    		GPIO_WriteBit(GPIOC, GPIO_Pin_7, Bit_RESET);
    	else
    		GPIO_WriteBit(GPIOC, GPIO_Pin_7, Bit_SET);
    }
    
    int main(void)
    {
    
      //int i;
    
    	NVIC_Configuration();//配置  NVIC 和 Vector Table 
       
    	Uart1_COMInit(115200); //串口1连接v210或PC机
    
     	SPI1_Init();
    	SPIsend_Init();  
    	send_onoff(Bit_RESET);
    
    	Uart_SendString(USART1,"串口1开始：\r\n") ;	//串口1接PC机
    
    
    	while (1)
    	{
    		 SPItest();
    	}
       
    }
    
    void send_data(int mode)
    {
    	int i;
    	send_onoff(Bit_SET);
    	switch(mode)
    	{
    		case 0x01:
    			for(i=0;i<38;i++)
    			{
    				SPI_I2S_SendData(SPI1,i + 1);
    			}
    			break;
    		case 0x02:
    			for(i=0;i<38;i++)
    			{
    				SPI_I2S_SendData(SPI1,i + 2);
    			}
    			break;
    
    		case 0x03:
    			for(i=0;i<38;i++)
    			{
    				SPI_I2S_SendData(SPI1,i + 3);
    			}
    			break;
    		default:
    			break;
    	}
    	send_onoff(Bit_RESET);
    	cmd = 0;
    	return;
    }
    
    void SPItest(void)
    {
    	int i;
    	//static int	x=0;
    
    	if(RxIdx==SPI_BufferSize) //中断方式接收
    	{
    		cmd = SPI1_Buffer_Rx[0];
    		for(i=0;i< RxIdx;i++)
    		{
    			Uart_SendByte(USART1,SPI1_Buffer_Rx[i]);//向PC机发送
    			// SPI_I2S_SendData(SPI1,0xff); 
    		 	SPI1_Buffer_Rx[i]=0;
    		}
    		//while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);
    		//SPI_I2S_SendData(SPI1,x++);
    		//send_onoff(1);
    		//SPI_I2S_ITConfig(SPI1, SPI_I2S_IT_RXNE, ENABLE);
    		//Delay_ARMJISHU(10000000);
    		RxIdx=0;
    		SPI_I2S_ITConfig(SPI1, SPI_I2S_IT_RXNE, ENABLE);
    	}
    
    	if(cmd)
    	send_data(cmd);
     //查询方式接收：
    /*
    	while (SPI_I2S_GetFlagStatus(SPI3, SPI_I2S_FLAG_RXNE) == RESET);
        SPI3_Buffer_Rx[RxIdx++] = SPI_I2S_ReceiveData(SPI3);
    	if(RxIdx==SPI_BufferSize)
    	{
    		for(i=0;i< RxIdx;i++)
    		{
    	  	Uart_SendByte(USART1,SPI3_Buffer_Rx[i]);//向PC机发送
    
    		}
    		RxIdx=0;
    	}
    */
    }
    
    void UARTtest(USART_TypeDef *port)
    {
    int i;
    	
    	for(i=0;i<10;i++)
    		Uart_SendByte(port,'0'+i);
    	Delay_ARMJISHU(10000000);
    
    }

具体代码我就不作说明了

[Link 1]: http://download.csdn.net/detail/hclydao/6414507