xref: /linux/drivers/infiniband/hw/hfi1/device.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright(c) 2015, 2016 Intel Corporation.
4  */
5 
6 #include <linux/cdev.h>
7 #include <linux/device.h>
8 #include <linux/fs.h>
9 
10 #include "hfi.h"
11 #include "device.h"
12 
13 static char *hfi1_user_devnode(const struct device *dev, umode_t *mode)
14 {
15 	if (mode)
16 		*mode = 0666;
17 	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
18 }
19 
20 static const struct class user_class = {
21 	.name = "hfi1_user",
22 	.devnode = hfi1_user_devnode,
23 };
24 static dev_t hfi1_dev;
25 
26 int hfi1_cdev_init(int minor, const char *name,
27 		   const struct file_operations *fops,
28 		   struct cdev *cdev, struct device **devp,
29 		   struct kobject *parent)
30 {
31 	const dev_t dev = MKDEV(MAJOR(hfi1_dev), minor);
32 	struct device *device = NULL;
33 	int ret;
34 
35 	cdev_init(cdev, fops);
36 	cdev->owner = THIS_MODULE;
37 	cdev_set_parent(cdev, parent);
38 	kobject_set_name(&cdev->kobj, name);
39 
40 	ret = cdev_add(cdev, dev, 1);
41 	if (ret < 0) {
42 		pr_err("Could not add cdev for minor %d, %s (err %d)\n",
43 		       minor, name, -ret);
44 		goto done;
45 	}
46 
47 	device = device_create(&user_class, NULL, dev, NULL, "%s", name);
48 
49 	if (IS_ERR(device)) {
50 		ret = PTR_ERR(device);
51 		pr_err("Could not create device for minor %d, %s (err %pe)\n",
52 		       minor, name, device);
53 		device = NULL;
54 		cdev_del(cdev);
55 	}
56 done:
57 	*devp = device;
58 	return ret;
59 }
60 
61 void hfi1_cdev_cleanup(struct cdev *cdev, struct device **devp)
62 {
63 	struct device *device = *devp;
64 
65 	if (device) {
66 		device_unregister(device);
67 		*devp = NULL;
68 
69 		cdev_del(cdev);
70 	}
71 }
72 
73 static const char *hfi1_class_name = "hfi1";
74 
75 const char *class_name(void)
76 {
77 	return hfi1_class_name;
78 }
79 
80 int __init dev_init(void)
81 {
82 	int ret;
83 
84 	ret = alloc_chrdev_region(&hfi1_dev, 0, HFI1_NMINORS, DRIVER_NAME);
85 	if (ret < 0) {
86 		pr_err("Could not allocate chrdev region (err %d)\n", -ret);
87 		return ret;
88 	}
89 
90 	ret = class_register(&user_class);
91 	if (ret) {
92 		pr_err("Could not create device class for user accessible files (err %d)\n",
93 		       -ret);
94 		unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
95 	}
96 
97 	return ret;
98 }
99 
100 void dev_cleanup(void)
101 {
102 	class_unregister(&user_class);
103 	unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
104 }
105