lp.c

arm平台上的uclinux系统全部源代码

	   we may still want to open it to perform ioctl()s.  Therefore we
	   have commandeered O_NONBLOCK, even though it is being used in
	   a non-standard manner.  This is strictly a Linux hack, and
	   should most likely only ever be used by the tunelp application. */
	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
		int status = LP_S(minor);
		if (status & LP_POUTPA) {
			printk(KERN_INFO "lp%d out of paper\n", minor);
			MOD_DEC_USE_COUNT;
			return -ENOSPC;
		} else if (!(status & LP_PSELECD)) {
			printk(KERN_INFO "lp%d off-line\n", minor);
			MOD_DEC_USE_COUNT;
			return -EIO;
		} else if (!(status & LP_PERRORP)) {
			printk(KERN_ERR "lp%d printer error\n", minor);
			MOD_DEC_USE_COUNT;
			return -EIO;
		}
	}

	if ((irq = LP_IRQ(minor)) != NO_IRQ) {
		lp_table[minor].lp_buffer = (char *) kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
		if (!lp_table[minor].lp_buffer) {
			MOD_DEC_USE_COUNT;
			return -ENOMEM;
		}

		ret = request_irq(irq, lp_interrupt, SA_INTERRUPT, "printer", NULL);
		if (ret) {
			kfree_s(lp_table[minor].lp_buffer, LP_BUFFER_SIZE);
			lp_table[minor].lp_buffer = NULL;
			printk("lp%d unable to use interrupt %d, error %d\n", minor, irq, ret);
			MOD_DEC_USE_COUNT;
			return ret;
		}
	}

	LP_F(minor) |= LP_BUSY;
	return 0;
}

static void lp_release(struct inode * inode, struct file * file)
{
	unsigned int minor = MINOR(inode->i_rdev);
	unsigned int irq;

	if ((irq = LP_IRQ(minor)) != NO_IRQ) {
		free_irq(irq, NULL);
		kfree_s(lp_table[minor].lp_buffer, LP_BUFFER_SIZE);
		lp_table[minor].lp_buffer = NULL;
	}

	LP_F(minor) &= ~LP_BUSY;
	MOD_DEC_USE_COUNT;
}


static int lp_ioctl(struct inode *inode, struct file *file,
		    unsigned int cmd, unsigned long arg)
{
	unsigned int minor = MINOR(inode->i_rdev);
	int retval = 0;

#ifdef LP_DEBUG
	printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%x\n", minor, cmd, arg);
#endif
	if (minor >= LP_NO)
		return -ENODEV;
	if ((LP_F(minor) & LP_EXIST) == 0)
		return -ENODEV;
	switch ( cmd ) {
		case LPTIME:
			LP_TIME(minor) = arg * HZ/100;
			break;
		case LPCHAR:
			LP_CHAR(minor) = arg;
			break;
		case LPABORT:
			if (arg)
				LP_F(minor) |= LP_ABORT;
			else
				LP_F(minor) &= ~LP_ABORT;
			break;
		case LPABORTOPEN:
			if (arg)
				LP_F(minor) |= LP_ABORTOPEN;
			else
				LP_F(minor) &= ~LP_ABORTOPEN;
			break;
		case LPCAREFUL:
			if (arg)
				LP_F(minor) |= LP_CAREFUL;
			else
				LP_F(minor) &= ~LP_CAREFUL;
			break;
		case LPWAIT:
			LP_WAIT(minor) = arg;
			break;
		case LPSETIRQ: {
			int oldirq;
			int newirq = arg;
			struct lp_struct *lp = &lp_table[minor];

			if (!suser())
				return -EPERM;

			oldirq = LP_IRQ(minor);

			/* Allocate buffer now if we are going to need it */
			if (oldirq == NO_IRQ && newirq != NO_IRQ) {
				lp->lp_buffer = (char *) kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
				if (!lp->lp_buffer)
					return -ENOMEM;
			}

			if (oldirq != NO_IRQ) {
				free_irq(oldirq, NULL);
			}
			if (newirq != NO_IRQ) {
				/* Install new irq */
				if ((retval = request_irq(newirq, lp_interrupt, SA_INTERRUPT, "printer", NULL))) {
					if (oldirq != NO_IRQ) {
						/* restore old irq */
						request_irq(oldirq, lp_interrupt, SA_INTERRUPT, "printer", NULL);
					} else {
						/* We don't need the buffer */
						kfree_s(lp->lp_buffer, LP_BUFFER_SIZE);
						lp->lp_buffer = NULL;
					}
					return retval;
				}
			}
			if (oldirq != NO_IRQ && newirq == NO_IRQ) {
				/* We don't need the buffer */
				kfree_s(lp->lp_buffer, LP_BUFFER_SIZE);
				lp->lp_buffer = NULL;
			}
			LP_IRQ(minor) = newirq;
			lp_reset(minor);
			break;
		}
		case LPGETIRQ:
			retval = verify_area(VERIFY_WRITE, (void *) arg,
			    sizeof(int));
		    	if (retval)
		    		return retval;
			memcpy_tofs((int *) arg, &LP_IRQ(minor), sizeof(int));
			break;
		case LPGETSTATUS:
			retval = verify_area(VERIFY_WRITE, (void *) arg,
			    sizeof(int));
		    	if (retval)
		    		return retval;
			else {
				int status = LP_S(minor);
				memcpy_tofs((int *) arg, &status, sizeof(int));
			}
			break;
		case LPRESET:
			lp_reset(minor);
			break;
		case LPGETSTATS:
			retval = verify_area(VERIFY_WRITE, (void *) arg,
			    sizeof(struct lp_stats));
		    	if (retval)
		    		return retval;
			else {
				memcpy_tofs((int *) arg, &LP_STAT(minor), sizeof(struct lp_stats));
				if (suser())
					memset(&LP_STAT(minor), 0, sizeof(struct lp_stats));
			}
			break;
 		case LPGETFLAGS:
 			retval = verify_area(VERIFY_WRITE, (void *) arg,
 			    sizeof(int));
 		    	if (retval)
 		    		return retval;
 			else {
 				int status = LP_F(minor);
				memcpy_tofs((int *) arg, &status, sizeof(int));
			}
			break;
		default:
			retval = -EINVAL;
	}
	return retval;
}


static struct file_operations lp_fops = {
	lp_lseek,
	NULL,		/* lp_read */
	lp_write,
	NULL,		/* lp_readdir */
	NULL,		/* lp_select */
	lp_ioctl,
	NULL,		/* lp_mmap */
	lp_open,
	lp_release
};

static int lp_probe(int offset)
{
	int base, size;
	unsigned int testvalue;

	base = LP_B(offset);
	if (base == 0) 
		return -1;		/* de-configured by command line */
	if (LP_IRQ(offset) != NO_IRQ && LP_IRQ(offset) > 15) 
		return -1;		/* bogus interrupt value */
	size = (base == 0x3bc)? 3 : 8;
	if (check_region(base, size) < 0)
		return -1;
	/* write to port & read back to check */
	outb_p(LP_DUMMY, base);
	udelay(LP_DELAY);
	testvalue = inb_p(base);
	if (testvalue == LP_DUMMY) {
		LP_F(offset) |= LP_EXIST;
		lp_reset(offset);
		printk(KERN_INFO "lp%d at 0x%04x, ", offset, base);
		request_region(base, size, "lp");
		if (LP_IRQ(offset) != NO_IRQ)
			printk("(irq = %d)\n", LP_IRQ(offset));
		else
			printk("(polling)\n");
		return 1;
	} else
		return 0;
}

/* Command line parameters:

   When the lp driver is built in to the kernel, you may use the
   LILO/LOADLIN command line to set the port addresses and interrupts
   that the driver will use.

   Syntax:	lp=port0[,irq0[,port1[,irq1[,port2[,irq2]]]]]

   For example:   lp=0x378,0   or   lp=0x278,5,0x378,7

   Note that if this feature is used, you must specify *all* the ports
   you want considered, there are no defaults.  You can disable a
   built-in driver with lp=0 .

*/

void	lp_setup(char *str, int *ints)

{	
        LP_B(0)   = ((ints[0] > 0) ? ints[1] : 0 );
        LP_IRQ(0) = ((ints[0] > 1) ? ints[2] : NO_IRQ );
        LP_B(1)   = ((ints[0] > 2) ? ints[3] : 0 );
        LP_IRQ(1) = ((ints[0] > 3) ? ints[4] : NO_IRQ );
        LP_B(2)   = ((ints[0] > 4) ? ints[5] : 0 );
        LP_IRQ(2) = ((ints[0] > 5) ? ints[6] : NO_IRQ );
}

#ifdef MODULE
static int io[] = {0, 0, 0};
static int irq[] = {NO_IRQ, NO_IRQ, NO_IRQ};

#define lp_init init_module
#endif

int lp_init(void)
{
	int offset = 0;
	int count = 0;
#ifdef MODULE
	int failed = 0;
#endif

	if (register_chrdev(LP_MAJOR,"lp",&lp_fops)) {
		printk("lp: unable to get major %d\n", LP_MAJOR);
		return -EIO;
	}
#ifdef MODULE
	/* When user feeds parameters, use them */
	for (offset=0; offset < LP_NO; offset++) {
		int specified=0;

		if (io[offset] != 0) {
			LP_B(offset) = io[offset];
			specified++;
		}
		if (irq[offset] != NO_IRQ) {
			LP_IRQ(offset) = irq[offset];
			specified++;
		}
		if (specified) {
			if (lp_probe(offset) <= 0) {
				printk(KERN_INFO "lp%d: Not found\n", offset);
				failed++;
			} else
				count++;
		}
	}
	/* Successful specified devices increase count
	 * Unsuccessful specified devices increase failed
	 */
	if (count)
		return 0;
	if (failed) {
		printk(KERN_INFO "lp: No override devices found.\n");
		unregister_chrdev(LP_MAJOR,"lp");
		return -EIO;
	}
	/* Only get here if there were no specified devices. To continue 
	 * would be silly since the above code has scribbled all over the
	 * probe list.
	 */
#endif
	/* take on all known port values */
	for (offset = 0; offset < LP_NO; offset++) {
		int ret = lp_probe(offset);
		if (ret < 0)
			continue;
		count += ret;
	}
	if (count == 0)
		printk("lp: Driver configured but no interfaces found.\n");

	return 0;
}

#ifdef MODULE
void cleanup_module(void)
{
	int offset;

	unregister_chrdev(LP_MAJOR,"lp");
	for (offset = 0; offset < LP_NO; offset++) {
		int base, size;
		base = LP_B(offset);
		size = (base == 0x3bc)? 3 : 8;
		if (LP_F(offset) & LP_EXIST)
			release_region(LP_B(offset),size);
	}
}
#endif