xref: /openbmc/linux/drivers/usb/core/endpoint.c (revision 28dce2c4)
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/usb.h>
18 #include "usb.h"
19 
20 struct ep_device {
21 	struct usb_endpoint_descriptor *desc;
22 	struct usb_device *udev;
23 	struct device dev;
24 };
25 #define to_ep_device(_dev) \
26 	container_of(_dev, struct ep_device, dev)
27 
28 struct ep_attribute {
29 	struct attribute attr;
30 	ssize_t (*show)(struct usb_device *,
31 			struct usb_endpoint_descriptor *, char *);
32 };
33 #define to_ep_attribute(_attr) \
34 	container_of(_attr, struct ep_attribute, attr)
35 
36 #define usb_ep_attr(field, format_string)			\
37 static ssize_t field##_show(struct device *dev,			\
38 			       struct device_attribute *attr,	\
39 			       char *buf)			\
40 {								\
41 	struct ep_device *ep = to_ep_device(dev);		\
42 	return sprintf(buf, format_string, ep->desc->field);	\
43 }								\
44 static DEVICE_ATTR_RO(field)
45 
46 usb_ep_attr(bLength, "%02x\n");
47 usb_ep_attr(bEndpointAddress, "%02x\n");
48 usb_ep_attr(bmAttributes, "%02x\n");
49 usb_ep_attr(bInterval, "%02x\n");
50 
51 static ssize_t wMaxPacketSize_show(struct device *dev,
52 				   struct device_attribute *attr, char *buf)
53 {
54 	struct ep_device *ep = to_ep_device(dev);
55 	return sprintf(buf, "%04x\n", usb_endpoint_maxp(ep->desc));
56 }
57 static DEVICE_ATTR_RO(wMaxPacketSize);
58 
59 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
60 			 char *buf)
61 {
62 	struct ep_device *ep = to_ep_device(dev);
63 	char *type = "unknown";
64 
65 	switch (usb_endpoint_type(ep->desc)) {
66 	case USB_ENDPOINT_XFER_CONTROL:
67 		type = "Control";
68 		break;
69 	case USB_ENDPOINT_XFER_ISOC:
70 		type = "Isoc";
71 		break;
72 	case USB_ENDPOINT_XFER_BULK:
73 		type = "Bulk";
74 		break;
75 	case USB_ENDPOINT_XFER_INT:
76 		type = "Interrupt";
77 		break;
78 	}
79 	return sprintf(buf, "%s\n", type);
80 }
81 static DEVICE_ATTR_RO(type);
82 
83 static ssize_t interval_show(struct device *dev, struct device_attribute *attr,
84 			     char *buf)
85 {
86 	struct ep_device *ep = to_ep_device(dev);
87 	unsigned int interval;
88 	char unit;
89 
90 	interval = usb_decode_interval(ep->desc, ep->udev->speed);
91 	if (interval % 1000) {
92 		unit = 'u';
93 	} else {
94 		unit = 'm';
95 		interval /= 1000;
96 	}
97 
98 	return sprintf(buf, "%d%cs\n", interval, unit);
99 }
100 static DEVICE_ATTR_RO(interval);
101 
102 static ssize_t direction_show(struct device *dev, struct device_attribute *attr,
103 			      char *buf)
104 {
105 	struct ep_device *ep = to_ep_device(dev);
106 	char *direction;
107 
108 	if (usb_endpoint_xfer_control(ep->desc))
109 		direction = "both";
110 	else if (usb_endpoint_dir_in(ep->desc))
111 		direction = "in";
112 	else
113 		direction = "out";
114 	return sprintf(buf, "%s\n", direction);
115 }
116 static DEVICE_ATTR_RO(direction);
117 
118 static struct attribute *ep_dev_attrs[] = {
119 	&dev_attr_bLength.attr,
120 	&dev_attr_bEndpointAddress.attr,
121 	&dev_attr_bmAttributes.attr,
122 	&dev_attr_bInterval.attr,
123 	&dev_attr_wMaxPacketSize.attr,
124 	&dev_attr_interval.attr,
125 	&dev_attr_type.attr,
126 	&dev_attr_direction.attr,
127 	NULL,
128 };
129 static const struct attribute_group ep_dev_attr_grp = {
130 	.attrs = ep_dev_attrs,
131 };
132 static const struct attribute_group *ep_dev_groups[] = {
133 	&ep_dev_attr_grp,
134 	NULL
135 };
136 
137 static void ep_device_release(struct device *dev)
138 {
139 	struct ep_device *ep_dev = to_ep_device(dev);
140 
141 	kfree(ep_dev);
142 }
143 
144 struct device_type usb_ep_device_type = {
145 	.name =		"usb_endpoint",
146 	.release = ep_device_release,
147 };
148 
149 int usb_create_ep_devs(struct device *parent,
150 			struct usb_host_endpoint *endpoint,
151 			struct usb_device *udev)
152 {
153 	struct ep_device *ep_dev;
154 	int retval;
155 
156 	ep_dev = kzalloc(sizeof(*ep_dev), GFP_KERNEL);
157 	if (!ep_dev) {
158 		retval = -ENOMEM;
159 		goto exit;
160 	}
161 
162 	ep_dev->desc = &endpoint->desc;
163 	ep_dev->udev = udev;
164 	ep_dev->dev.groups = ep_dev_groups;
165 	ep_dev->dev.type = &usb_ep_device_type;
166 	ep_dev->dev.parent = parent;
167 	dev_set_name(&ep_dev->dev, "ep_%02x", endpoint->desc.bEndpointAddress);
168 
169 	retval = device_register(&ep_dev->dev);
170 	if (retval)
171 		goto error_register;
172 
173 	device_enable_async_suspend(&ep_dev->dev);
174 	endpoint->ep_dev = ep_dev;
175 	return retval;
176 
177 error_register:
178 	put_device(&ep_dev->dev);
179 exit:
180 	return retval;
181 }
182 
183 void usb_remove_ep_devs(struct usb_host_endpoint *endpoint)
184 {
185 	struct ep_device *ep_dev = endpoint->ep_dev;
186 
187 	if (ep_dev) {
188 		device_unregister(&ep_dev->dev);
189 		endpoint->ep_dev = NULL;
190 	}
191 }
192