/alps/bar_resolve

#include <linux/init.h>

#include <linux/module.h>

#include <linux/device.h>

#include <linux/types.h>

#include <linux/cdev.h>

#include <linux/fs.h>

#include <linux/slab.h>

#include <linux/semaphore.h>

#include "mod.h"

#include "dev.h"

#include "debug.h"

#include "sysfs.h"

MODULE_LICENSE("GPL v2");

MODULE_AUTHOR("Suren A. Chilingaryan <csa@suren.me>");

MODULE_DESCRIPTION("Testing module");

MODULE_VERSION("0.0.1");

int test_minors = TEST_MINORS;

module_param(test_minors, int, S_IRUGO);

static dev_t test_devno;			/**< major number */

static test_dev_t **test_devs = NULL;	        /**< per-device context */

static DEFINE_SEMAPHORE(test_devs_mtx);            /**< mutex protecting creation/destruction of devices */

static struct class *test_class;		/**< device class */

static void test_module_destroy_cdev(test_dev_t *test)

{

    if (test->dev) {

	test_sysfs_free(test);

	device_destroy(test_class, test->devno);

    }

    cdev_del(&test->cdev);

    kfree(test);

}

static int test_module_setup_cdev(void)

{

    int i;

    int err = 0;

    dev_t devno;

    test_dev_t *test;

    test = kmalloc(sizeof(test_dev_t), GFP_KERNEL);

    if (!test) {

	mod_info("Couldn't allocate memory. Device is not created.\n");

	return -ENOMEM;

    }

    cdev_init(&test->cdev, test_get_fops());

    test->cdev.owner = THIS_MODULE;

    test->cdev.ops = test_get_fops();

    down(&test_devs_mtx);

    for (i = 0; i < test_minors; i++) {

	if (!test_devs[i])

	    break;

    }

    if (i == test_minors) {

	mod_info("No free minor numbers left");

	err = -EBUSY;

	goto fail;

    }

    devno = MKDEV(MAJOR(test_devno), MINOR(test_devno) + i);

    test->devno = devno;

    err = cdev_add(&test->cdev, devno, 1);

    if (err) {

	mod_info("Error %d adding device kmm%d", err, i);

	goto fail;

    }

    test->dev = device_create(test_class, NULL, devno, test, TEST_NODE_FMT, MINOR(test_devno) + i);

    if (!test->dev) {

	mod_info("Error creating /dev/%s%d\n", TEST_NODE, MINOR(test_devno) + i);

	goto fail;

    }

    dev_set_drvdata(test->dev, test);

    test_devs[i] = test;

    up(&test_devs_mtx);

    err = test_sysfs_init(test);

    if (err) goto fail_sysfs;

    mod_info("Device /dev/%s%d added\n", TEST_NODE, MINOR(test_devno) + i);

    return 0;

fail:

    up(&test_devs_mtx);

fail_sysfs:

    test_module_destroy_cdev(test);

    return err;

}

static void test_module_cleanup(void)

{

    int i;

    if (test_devs) {

	for (i = 0; i < test_minors; i++) {

	    if (test_devs[i])

		test_module_destroy_cdev(test_devs[i]);

	}

	kfree(test_devs);

    }

    if (test_class)

    	class_destroy(test_class);

    unregister_chrdev_region(test_devno, test_minors);

}

static int __init test_module_init(void)

{

    int err;

    if ((err = alloc_chrdev_region(&test_devno, 0, test_minors, TEST_NODE))) {

	mod_info("Couldn't allocate chrdev region. Module not loaded.\n");

	goto alloc_chrdev_fail;

    }

    test_class = class_create(THIS_MODULE, TEST_NODE);

    if (IS_ERR(test_class)) {

	mod_info("No sysfs support. Module not loaded.\n");

	goto fail;

    }

    test_devs = kmalloc(test_minors * sizeof(test_dev_t*), GFP_KERNEL);

    if (!test_devs) {

	mod_info("Couldn't allocate memory. Module not loaded.\n");

	err = -ENOMEM;

    }

    memset(test_devs, 0, test_minors * sizeof(test_dev_t*));

    mod_info("Major %d allocated to node '%s'\n", MAJOR(test_devno), TEST_NODE);

    err = test_module_setup_cdev();

    if (err) goto fail;

    return 0;

fail:

    test_module_cleanup();

alloc_chrdev_fail:

    return err;

}

static void __exit test_module_exit(void)

{

    test_module_cleanup();

}

module_init(test_module_init);

module_exit(test_module_exit);