/*
* Module housekeeping.
*/
static int simple_init(void)
{
int result;
dev_t dev = MKDEV(simple_major, 0);
/* Figure out our device number. */
if (simple_major)
result = register_chrdev_region(dev, 2, "simple");
else {
result = alloc_chrdev_region(&dev, 0, 2, "simple");
simple_major = MAJOR(dev);
}
if (result < 0) {
printk(KERN_WARNING "simple: unable to get major %d\n", simple_major);
return result;
}
if (simple_major == 0)
simple_major = result;
/* Now set up two cdevs. */
simple_setup_cdev(SimpleDevs, 0, &simple_remap_ops);
simple_setup_cdev(SimpleDevs + 1, 1, &simple_nopage_ops);
return 0;
}
static int simple_init(void)
{
int result = 0;
static dev_t dev_no;
printk(KERN_INFO "%s()\n", __func__);
result = kfifo_alloc(&fifo, FIFO_SIZE, GFP_KERNEL);
if (result) {
printk(KERN_ERR "error kfifo_alloc\n");
goto kfifo_alloc_err;
}
printk(KERN_INFO "%s() : kfifo size = %lu\n", __func__, FIFO_SIZE);
result = alloc_chrdev_region(&dev_no, 0, 2, "simple");
if (result < 0) {
printk(KERN_WARNING "simple: unable to get major %d\n",
simple_major);
result = -EPERM;
goto alloc_chedev_region_fail;
}
simple_major = MAJOR(dev_no);
simple_minor = MINOR(dev_no);
printk(KERN_INFO "%s() : Simple driver for 2 devices\n", __func__);
printk(KERN_INFO "Major=%d,Minor=%d\n", simple_major, simple_minor);
printk(KERN_INFO "MajoR=%d,Minor=%d\n", simple_major, (simple_minor+1));
cl = class_create(THIS_MODULE, "chardrv");
if (cl == NULL) {
result = -EPERM;
goto class_create_fail;
}
/* Now set up two cdevs. */
result = simple_setup_cdev(simple_cdev, 0, &prod_ops,
"prod");
if (result < 0) {
if (result == -DEVADDERR)
goto dev_add_err_0;
else
goto dev_create_err_0;
}
result = simple_setup_cdev(simple_cdev + 1, 1, &cons_ops,
"cons");
if (result < 0) {
if (result == -DEVADDERR)
goto dev_add_err_1;
else
goto dev_create_err_1;
}
sema_init(&prod_sem, 1);
sema_init(&cons_sem, 1);
init_waitqueue_head(&prod_que);
init_waitqueue_head(&cons_que);
goto init_success;
dev_add_err_1:
cdev_del(simple_cdev + 1);
dev_create_err_1:
dev_add_err_0:
cdev_del(simple_cdev);
dev_create_err_0:
class_create_fail:
unregister_chrdev_region(MKDEV(simple_major, simple_minor), 2);
alloc_chedev_region_fail:
kfifo_alloc_err:
result = -1;
init_success:
return result;
}