vfc_dev.c

该文件是rt_linux

/*
 * drivers/sbus/char/vfc_dev.c
 *
 * Driver for the Videopix Frame Grabber.
 * 
 * In order to use the VFC you need to program the video controller
 * chip. This chip is the Phillips SAA9051.  You need to call their
 * documentation ordering line to get the docs.
 *
 * There is very little documentation on the VFC itself.  There is
 * some useful info that can be found in the manuals that come with
 * the card.  I will hopefully write some better docs at a later date.
 *
 * Copyright (C) 1996 Manish Vachharajani ([e-mail])
 * */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/smp_lock.h>
#include <linux/delay.h>
#include <linux/spinlock.h>

#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sbus.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>

#define VFC_MAJOR (60)

#if 0
#define VFC_IOCTL_DEBUG
#endif

#include "vfc.h"
#include <asm/vfc_ioctls.h>

static struct file_operations vfc_fops;
static devfs_handle_t devfs_handle;  /*  For the directory  */
struct vfc_dev **vfc_dev_lst;
static char vfcstr[]="vfc";
static unsigned char saa9051_init_array[VFC_SAA9051_NR] = {
	0x00, 0x64, 0x72, 0x52,
	0x36, 0x18, 0xff, 0x20,
	0xfc, 0x77, 0xe3, 0x50,
	0x3e
};

void vfc_lock_device(struct vfc_dev *dev)
{
	down(&dev->device_lock_sem);
}

void vfc_unlock_device(struct vfc_dev *dev)
{
	up(&dev->device_lock_sem);
}


void vfc_captstat_reset(struct vfc_dev *dev) 
{
	dev->control_reg |= VFC_CONTROL_CAPTRESET;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg &= ~VFC_CONTROL_CAPTRESET;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg |= VFC_CONTROL_CAPTRESET;
	sbus_writel(dev->control_reg, &dev->regs->control);
}

void vfc_memptr_reset(struct vfc_dev *dev) 
{
	dev->control_reg |= VFC_CONTROL_MEMPTR;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg &= ~VFC_CONTROL_MEMPTR;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg |= VFC_CONTROL_MEMPTR; 
	sbus_writel(dev->control_reg, &dev->regs->control);
}

int vfc_csr_init(struct vfc_dev *dev)
{
	dev->control_reg = 0x80000000;
	sbus_writel(dev->control_reg, &dev->regs->control);
	udelay(200); 
	dev->control_reg &= ~0x80000000;
	sbus_writel(dev->control_reg, &dev->regs->control);
	udelay(100); 
	sbus_writel(0x0f000000, &dev->regs->i2c_magic2);

	vfc_memptr_reset(dev);

	dev->control_reg &= ~VFC_CONTROL_DIAGMODE;
	dev->control_reg &= ~VFC_CONTROL_CAPTURE;
	dev->control_reg |= 0x40000000;
	sbus_writel(dev->control_reg, &dev->regs->control);

	vfc_captstat_reset(dev);

	return 0;
}

int vfc_saa9051_init(struct vfc_dev *dev)
{
	int i;

	for (i = 0; i < VFC_SAA9051_NR; i++)
		dev->saa9051_state_array[i] = saa9051_init_array[i];

	vfc_i2c_sendbuf(dev,VFC_SAA9051_ADDR,
			dev->saa9051_state_array, VFC_SAA9051_NR);
	return 0;
}

int init_vfc_hw(struct vfc_dev *dev) 
{
	vfc_lock_device(dev);
	vfc_csr_init(dev);

	vfc_pcf8584_init(dev);
	vfc_init_i2c_bus(dev); /* hopefully this doesn't undo the magic
				  sun code above*/
	vfc_saa9051_init(dev);
	vfc_unlock_device(dev);
	return 0; 
}

int init_vfc_devstruct(struct vfc_dev *dev, int instance) 
{
	dev->instance=instance;
	init_MUTEX(&dev->device_lock_sem);
	dev->control_reg=0;
	init_waitqueue_head(&dev->poll_wait);
	dev->busy=0;
	return 0;
}

int init_vfc_device(struct sbus_dev *sdev,struct vfc_dev *dev, int instance)
{
	char devname[8];

	if(dev == NULL) {
		printk(KERN_ERR "VFC: Bogus pointer passed\n");
		return -ENOMEM;
	}
	printk("Initializing vfc%d\n",instance);
	dev->regs = NULL;
	dev->regs = (volatile struct vfc_regs *)
		sbus_ioremap(&sdev->resource[0], 0,
			     sizeof(struct vfc_regs), vfcstr);
	dev->which_io = sdev->reg_addrs[0].which_io;
	dev->phys_regs = (struct vfc_regs *) sdev->reg_addrs[0].phys_addr;
	if (dev->regs == NULL)
		return -EIO;

	printk("vfc%d: registers mapped at phys_addr: 0x%lx\n    virt_addr: 0x%lx\n",
	       instance,(unsigned long)sdev->reg_addrs[0].phys_addr,(unsigned long)dev->regs);

	if (init_vfc_devstruct(dev, instance))
		return -EINVAL;
	if (init_vfc_hw(dev))
		return -EIO;

	sprintf (devname, "%d", instance);
	dev->de = devfs_register (devfs_handle, devname, DEVFS_FL_DEFAULT,
				  VFC_MAJOR, instance,
				  S_IFCHR | S_IRUSR | S_IWUSR,
				  &vfc_fops, NULL);
	return 0;
}


struct vfc_dev *vfc_get_dev_ptr(int instance) 
{
	return vfc_dev_lst[instance];
}

static spinlock_t vfc_dev_lock = SPIN_LOCK_UNLOCKED;

static int vfc_open(struct inode *inode, struct file *file) 
{
	struct vfc_dev *dev;

	spin_lock(&vfc_dev_lock);
	dev = vfc_get_dev_ptr(MINOR(inode->i_rdev));
	if (dev == NULL) {
		spin_unlock(&vfc_dev_lock);
		return -ENODEV;
	}
	if (dev->busy) {
		spin_unlock(&vfc_dev_lock);
		return -EBUSY;
	}

	dev->busy = 1;
	spin_unlock(&vfc_dev_lock);

	vfc_lock_device(dev);
	
	vfc_csr_init(dev);
	vfc_pcf8584_init(dev);
	vfc_init_i2c_bus(dev);
	vfc_saa9051_init(dev);
	vfc_memptr_reset(dev);
	vfc_captstat_reset(dev);
	
	vfc_unlock_device(dev);
	return 0;
}

static int vfc_release(struct inode *inode,struct file *file) 
{
	struct vfc_dev *dev;

	spin_lock(&vfc_dev_lock);
	dev = vfc_get_dev_ptr(MINOR(inode->i_rdev));
	if (!dev || !dev->busy) {
		spin_unlock(&vfc_dev_lock);
		return -EINVAL;
	}
	dev->busy = 0;
	spin_unlock(&vfc_dev_lock);
	return 0;
}

static int vfc_debug(struct vfc_dev *dev, int cmd, unsigned long arg) 
{
	struct vfc_debug_inout inout;
	unsigned char *buffer;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch(cmd) {
	case VFC_I2C_SEND:
		if(copy_from_user(&inout, (void *)arg, sizeof(inout)))
			return -EFAULT;

		buffer = kmalloc(inout.len*sizeof(char), GFP_KERNEL);
		if (buffer == NULL)
			return -ENOMEM;

		if(copy_from_user(buffer, inout.buffer, 
				  inout.len*sizeof(char))) {
			kfree(buffer);
			return -EFAULT;
		}
		

		vfc_lock_device(dev);
		inout.ret=
			vfc_i2c_sendbuf(dev,inout.addr & 0xff,
					inout.buffer,inout.len);

		if (copy_to_user((void *)arg,&inout,sizeof(inout))) {
			kfree(buffer);
			return -EFAULT;
		}
		vfc_unlock_device(dev);

		break;
	case VFC_I2C_RECV:
		if (copy_from_user(&inout, (void *)arg, sizeof(inout)))
			return -EFAULT;

		buffer = kmalloc(inout.len, GFP_KERNEL);
		if (buffer == NULL)
			return -ENOMEM;

		memset(buffer,0,inout.len*sizeof(char));
		vfc_lock_device(dev);
		inout.ret=
			vfc_i2c_recvbuf(dev,inout.addr & 0xff
					,buffer,inout.len);
		vfc_unlock_device(dev);
		
		if (copy_to_user(inout.buffer, buffer, inout.len)) {
			kfree(buffer);
			return -EFAULT;
		}
		if (copy_to_user((void *)arg,&inout,sizeof(inout))) {
			kfree(buffer);
			return -EFAULT;
		}
		kfree(buffer);
		break;
	default:
		return -EINVAL;
	};

	return 0;
}

int vfc_capture_start(struct vfc_dev *dev) 
{
	vfc_captstat_reset(dev);
	dev->control_reg = sbus_readl(&dev->regs->control);
	if((dev->control_reg & VFC_STATUS_CAPTURE)) {
		printk(KERN_ERR "vfc%d: vfc capture status not reset\n",
		       dev->instance);
		return -EIO;
	}

	vfc_lock_device(dev);
	dev->control_reg &= ~VFC_CONTROL_CAPTURE;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg |= VFC_CONTROL_CAPTURE;
	sbus_writel(dev->control_reg, &dev->regs->control);
	dev->control_reg &= ~VFC_CONTROL_CAPTURE;
	sbus_writel(dev->control_reg, &dev->regs->control);
	vfc_unlock_device(dev);

	return 0;
}

int vfc_capture_poll(struct vfc_dev *dev) 
{
	int timeout = 1000;

	while (!timeout--) {
		if (dev->regs->control & VFC_STATUS_CAPTURE)
			break;
		vfc_i2c_delay_no_busy(dev, 100);
	}
	if(!timeout) {
		printk(KERN_WARNING "vfc%d: capture timed out\n",
		       dev->instance);
		return -ETIMEDOUT;
	}
	return 0;
}



static int vfc_set_control_ioctl(struct inode *inode, struct file *file, 
			  struct vfc_dev *dev, unsigned long arg) 
{
	int setcmd, ret = 0;

	if (copy_from_user(&setcmd,(void *)arg,sizeof(unsigned int)))
		return -EFAULT;

	VFC_IOCTL_DEBUG_PRINTK(("vfc%d: IOCTL(VFCSCTRL) arg=0x%x\n",
				dev->instance,setcmd));

	switch(setcmd) {
	case MEMPRST:
		vfc_lock_device(dev);
		vfc_memptr_reset(dev);
		vfc_unlock_device(dev);
		ret=0;
		break;
	case CAPTRCMD:
		vfc_capture_start(dev);
		vfc_capture_poll(dev);
		break;
	case DIAGMODE:
		if(capable(CAP_SYS_ADMIN)) {
			vfc_lock_device(dev);
			dev->control_reg |= VFC_CONTROL_DIAGMODE;
			sbus_writel(dev->control_reg, &dev->regs->control);
			vfc_unlock_device(dev);
			ret = 0;
		} else {
			ret = -EPERM; 
		}
		break;