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 struct class *class;
14 static struct class *user_class;
15 static dev_t hfi1_dev;
16 
hfi1_cdev_init(int minor,const char * name,const struct file_operations * fops,struct cdev * cdev,struct device ** devp,bool user_accessible,struct kobject * parent)17 int hfi1_cdev_init(int minor, const char *name,
18 		   const struct file_operations *fops,
19 		   struct cdev *cdev, struct device **devp,
20 		   bool user_accessible,
21 		   struct kobject *parent)
22 {
23 	const dev_t dev = MKDEV(MAJOR(hfi1_dev), minor);
24 	struct device *device = NULL;
25 	int ret;
26 
27 	cdev_init(cdev, fops);
28 	cdev->owner = THIS_MODULE;
29 	cdev_set_parent(cdev, parent);
30 	kobject_set_name(&cdev->kobj, name);
31 
32 	ret = cdev_add(cdev, dev, 1);
33 	if (ret < 0) {
34 		pr_err("Could not add cdev for minor %d, %s (err %d)\n",
35 		       minor, name, -ret);
36 		goto done;
37 	}
38 
39 	if (user_accessible)
40 		device = device_create(user_class, NULL, dev, NULL, "%s", name);
41 	else
42 		device = device_create(class, NULL, dev, NULL, "%s", name);
43 
44 	if (IS_ERR(device)) {
45 		ret = PTR_ERR(device);
46 		device = NULL;
47 		pr_err("Could not create device for minor %d, %s (err %d)\n",
48 			minor, name, -ret);
49 		cdev_del(cdev);
50 	}
51 done:
52 	*devp = device;
53 	return ret;
54 }
55 
hfi1_cdev_cleanup(struct cdev * cdev,struct device ** devp)56 void hfi1_cdev_cleanup(struct cdev *cdev, struct device **devp)
57 {
58 	struct device *device = *devp;
59 
60 	if (device) {
61 		device_unregister(device);
62 		*devp = NULL;
63 
64 		cdev_del(cdev);
65 	}
66 }
67 
68 static const char *hfi1_class_name = "hfi1";
69 
class_name(void)70 const char *class_name(void)
71 {
72 	return hfi1_class_name;
73 }
74 
hfi1_devnode(struct device * dev,umode_t * mode)75 static char *hfi1_devnode(struct device *dev, umode_t *mode)
76 {
77 	if (mode)
78 		*mode = 0600;
79 	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
80 }
81 
82 static const char *hfi1_class_name_user = "hfi1_user";
class_name_user(void)83 static const char *class_name_user(void)
84 {
85 	return hfi1_class_name_user;
86 }
87 
hfi1_user_devnode(struct device * dev,umode_t * mode)88 static char *hfi1_user_devnode(struct device *dev, umode_t *mode)
89 {
90 	if (mode)
91 		*mode = 0666;
92 	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
93 }
94 
dev_init(void)95 int __init dev_init(void)
96 {
97 	int ret;
98 
99 	ret = alloc_chrdev_region(&hfi1_dev, 0, HFI1_NMINORS, DRIVER_NAME);
100 	if (ret < 0) {
101 		pr_err("Could not allocate chrdev region (err %d)\n", -ret);
102 		goto done;
103 	}
104 
105 	class = class_create(THIS_MODULE, class_name());
106 	if (IS_ERR(class)) {
107 		ret = PTR_ERR(class);
108 		pr_err("Could not create device class (err %d)\n", -ret);
109 		unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
110 		goto done;
111 	}
112 	class->devnode = hfi1_devnode;
113 
114 	user_class = class_create(THIS_MODULE, class_name_user());
115 	if (IS_ERR(user_class)) {
116 		ret = PTR_ERR(user_class);
117 		pr_err("Could not create device class for user accessible files (err %d)\n",
118 		       -ret);
119 		class_destroy(class);
120 		class = NULL;
121 		user_class = NULL;
122 		unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
123 		goto done;
124 	}
125 	user_class->devnode = hfi1_user_devnode;
126 
127 done:
128 	return ret;
129 }
130 
dev_cleanup(void)131 void dev_cleanup(void)
132 {
133 	class_destroy(class);
134 	class = NULL;
135 
136 	class_destroy(user_class);
137 	user_class = NULL;
138 
139 	unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
140 }
141