xref: /linux/drivers/usb/core/endpoint.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * drivers/usb/core/endpoint.c
4  *
5  * (C) Copyright 2002,2004,2006 Greg Kroah-Hartman
6  * (C) Copyright 2002,2004 IBM Corp.
7  * (C) Copyright 2006 Novell Inc.
8  *
9  * Released under the GPLv2 only.
10  *
11  * Endpoint sysfs stuff
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/spinlock.h>
16 #include <linux/slab.h>
17 #include <linux/sysfs.h>
18 #include <linux/usb.h>
19 #include "usb.h"
20 
21 struct ep_device {
22 	struct usb_endpoint_descriptor *desc;
23 	struct usb_device *udev;
24 	struct device dev;
25 };
26 #define to_ep_device(_dev) \
27 	container_of(_dev, struct ep_device, dev)
28 
29 struct ep_attribute {
30 	struct attribute attr;
31 	ssize_t (*show)(struct usb_device *,
32 			struct usb_endpoint_descriptor *, char *);
33 };
34 #define to_ep_attribute(_attr) \
35 	container_of(_attr, struct ep_attribute, attr)
36 
37 #define usb_ep_attr(field, format_string)			\
38 static ssize_t field##_show(struct device *dev,			\
39 			       struct device_attribute *attr,	\
40 			       char *buf)			\
41 {								\
42 	struct ep_device *ep = to_ep_device(dev);		\
43 	return sysfs_emit(buf, format_string, ep->desc->field);	\
44 }								\
45 static DEVICE_ATTR_RO(field)
46 
47 usb_ep_attr(bLength, "%02x\n");
48 usb_ep_attr(bEndpointAddress, "%02x\n");
49 usb_ep_attr(bmAttributes, "%02x\n");
50 usb_ep_attr(bInterval, "%02x\n");
51 
52 static ssize_t wMaxPacketSize_show(struct device *dev,
53 				   struct device_attribute *attr, char *buf)
54 {
55 	struct ep_device *ep = to_ep_device(dev);
56 	return sysfs_emit(buf, "%04x\n", usb_endpoint_maxp(ep->desc));
57 }
58 static DEVICE_ATTR_RO(wMaxPacketSize);
59 
60 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
61 			 char *buf)
62 {
63 	struct ep_device *ep = to_ep_device(dev);
64 	char *type = "unknown";
65 
66 	switch (usb_endpoint_type(ep->desc)) {
67 	case USB_ENDPOINT_XFER_CONTROL:
68 		type = "Control";
69 		break;
70 	case USB_ENDPOINT_XFER_ISOC:
71 		type = "Isoc";
72 		break;
73 	case USB_ENDPOINT_XFER_BULK:
74 		type = "Bulk";
75 		break;
76 	case USB_ENDPOINT_XFER_INT:
77 		type = "Interrupt";
78 		break;
79 	}
80 	return sysfs_emit(buf, "%s\n", type);
81 }
82 static DEVICE_ATTR_RO(type);
83 
84 static ssize_t interval_show(struct device *dev, struct device_attribute *attr,
85 			     char *buf)
86 {
87 	struct ep_device *ep = to_ep_device(dev);
88 	unsigned int interval;
89 	char unit;
90 
91 	interval = usb_decode_interval(ep->desc, ep->udev->speed);
92 	if (interval % 1000) {
93 		unit = 'u';
94 	} else {
95 		unit = 'm';
96 		interval /= 1000;
97 	}
98 
99 	return sysfs_emit(buf, "%d%cs\n", interval, unit);
100 }
101 static DEVICE_ATTR_RO(interval);
102 
103 static ssize_t direction_show(struct device *dev, struct device_attribute *attr,
104 			      char *buf)
105 {
106 	struct ep_device *ep = to_ep_device(dev);
107 	char *direction;
108 
109 	if (usb_endpoint_xfer_control(ep->desc))
110 		direction = "both";
111 	else if (usb_endpoint_dir_in(ep->desc))
112 		direction = "in";
113 	else
114 		direction = "out";
115 	return sysfs_emit(buf, "%s\n", direction);
116 }
117 static DEVICE_ATTR_RO(direction);
118 
119 static struct attribute *ep_dev_attrs[] = {
120 	&dev_attr_bLength.attr,
121 	&dev_attr_bEndpointAddress.attr,
122 	&dev_attr_bmAttributes.attr,
123 	&dev_attr_bInterval.attr,
124 	&dev_attr_wMaxPacketSize.attr,
125 	&dev_attr_interval.attr,
126 	&dev_attr_type.attr,
127 	&dev_attr_direction.attr,
128 	NULL,
129 };
130 static const struct attribute_group ep_dev_attr_grp = {
131 	.attrs = ep_dev_attrs,
132 };
133 static const struct attribute_group *ep_dev_groups[] = {
134 	&ep_dev_attr_grp,
135 	NULL
136 };
137 
138 static void ep_device_release(struct device *dev)
139 {
140 	struct ep_device *ep_dev = to_ep_device(dev);
141 
142 	kfree(ep_dev);
143 }
144 
145 const struct device_type usb_ep_device_type = {
146 	.name =		"usb_endpoint",
147 	.release = ep_device_release,
148 };
149 
150 int usb_create_ep_devs(struct device *parent,
151 			struct usb_host_endpoint *endpoint,
152 			struct usb_device *udev)
153 {
154 	struct ep_device *ep_dev;
155 	int retval;
156 
157 	ep_dev = kzalloc(sizeof(*ep_dev), GFP_KERNEL);
158 	if (!ep_dev) {
159 		retval = -ENOMEM;
160 		goto exit;
161 	}
162 
163 	ep_dev->desc = &endpoint->desc;
164 	ep_dev->udev = udev;
165 	ep_dev->dev.groups = ep_dev_groups;
166 	ep_dev->dev.type = &usb_ep_device_type;
167 	ep_dev->dev.parent = parent;
168 	dev_set_name(&ep_dev->dev, "ep_%02x", endpoint->desc.bEndpointAddress);
169 
170 	retval = device_register(&ep_dev->dev);
171 	if (retval)
172 		goto error_register;
173 
174 	device_enable_async_suspend(&ep_dev->dev);
175 	endpoint->ep_dev = ep_dev;
176 	return retval;
177 
178 error_register:
179 	put_device(&ep_dev->dev);
180 exit:
181 	return retval;
182 }
183 
184 void usb_remove_ep_devs(struct usb_host_endpoint *endpoint)
185 {
186 	struct ep_device *ep_dev = endpoint->ep_dev;
187 
188 	if (ep_dev) {
189 		device_unregister(&ep_dev->dev);
190 		endpoint->ep_dev = NULL;
191 	}
192 }
193