usb/core/endpoint.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * drivers/usb/core/endpoint.c
0004  *
0005  * (C) Copyright 2002,2004,2006 Greg Kroah-Hartman
0006  * (C) Copyright 2002,2004 IBM Corp.
0007  * (C) Copyright 2006 Novell Inc.
0008  *
0009  * Released under the GPLv2 only.
0010  *
0011  * Endpoint sysfs stuff
0012  */
0013
0014 #include <linux/kernel.h>
0015 #include <linux/spinlock.h>
0016 #include <linux/slab.h>
0017 #include <linux/usb.h>
0018 #include "usb.h"
0019
0020 struct ep_device {
0021     struct usb_endpoint_descriptor *desc;
0022     struct usb_device *udev;
0023     struct device dev;
0024 };
0025 #define to_ep_device(_dev) \
0026     container_of(_dev, struct ep_device, dev)
0027
0028 struct ep_attribute {
0029     struct attribute attr;
0030     ssize_t (*show)(struct usb_device *,
0031             struct usb_endpoint_descriptor *, char *);
0032 };
0033 #define to_ep_attribute(_attr) \
0034     container_of(_attr, struct ep_attribute, attr)
0035
0036 #define usb_ep_attr(field, format_string)           \
0037 static ssize_t field##_show(struct device *dev,         \
0038                    struct device_attribute *attr,   \
0039                    char *buf)           \
0040 {                               \
0041     struct ep_device *ep = to_ep_device(dev);       \
0042     return sprintf(buf, format_string, ep->desc->field);    \
0043 }                               \
0044 static DEVICE_ATTR_RO(field)
0045
0046 usb_ep_attr(bLength, "%02x\n");
0047 usb_ep_attr(bEndpointAddress, "%02x\n");
0048 usb_ep_attr(bmAttributes, "%02x\n");
0049 usb_ep_attr(bInterval, "%02x\n");
0050
0051 static ssize_t wMaxPacketSize_show(struct device *dev,
0052                    struct device_attribute *attr, char *buf)
0053 {
0054     struct ep_device *ep = to_ep_device(dev);
0055     return sprintf(buf, "%04x\n", usb_endpoint_maxp(ep->desc));
0056 }
0057 static DEVICE_ATTR_RO(wMaxPacketSize);
0058
0059 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
0060              char *buf)
0061 {
0062     struct ep_device *ep = to_ep_device(dev);
0063     char *type = "unknown";
0064
0065     switch (usb_endpoint_type(ep->desc)) {
0066     case USB_ENDPOINT_XFER_CONTROL:
0067         type = "Control";
0068         break;
0069     case USB_ENDPOINT_XFER_ISOC:
0070         type = "Isoc";
0071         break;
0072     case USB_ENDPOINT_XFER_BULK:
0073         type = "Bulk";
0074         break;
0075     case USB_ENDPOINT_XFER_INT:
0076         type = "Interrupt";
0077         break;
0078     }
0079     return sprintf(buf, "%s\n", type);
0080 }
0081 static DEVICE_ATTR_RO(type);
0082
0083 static ssize_t interval_show(struct device *dev, struct device_attribute *attr,
0084                  char *buf)
0085 {
0086     struct ep_device *ep = to_ep_device(dev);
0087     unsigned int interval;
0088     char unit;
0089
0090     interval = usb_decode_interval(ep->desc, ep->udev->speed);
0091     if (interval % 1000) {
0092         unit = 'u';
0093     } else {
0094         unit = 'm';
0095         interval /= 1000;
0096     }
0097
0098     return sprintf(buf, "%d%cs\n", interval, unit);
0099 }
0100 static DEVICE_ATTR_RO(interval);
0101
0102 static ssize_t direction_show(struct device *dev, struct device_attribute *attr,
0103                   char *buf)
0104 {
0105     struct ep_device *ep = to_ep_device(dev);
0106     char *direction;
0107
0108     if (usb_endpoint_xfer_control(ep->desc))
0109         direction = "both";
0110     else if (usb_endpoint_dir_in(ep->desc))
0111         direction = "in";
0112     else
0113         direction = "out";
0114     return sprintf(buf, "%s\n", direction);
0115 }
0116 static DEVICE_ATTR_RO(direction);
0117
0118 static struct attribute *ep_dev_attrs[] = {
0119     &dev_attr_bLength.attr,
0120     &dev_attr_bEndpointAddress.attr,
0121     &dev_attr_bmAttributes.attr,
0122     &dev_attr_bInterval.attr,
0123     &dev_attr_wMaxPacketSize.attr,
0124     &dev_attr_interval.attr,
0125     &dev_attr_type.attr,
0126     &dev_attr_direction.attr,
0127     NULL,
0128 };
0129 static const struct attribute_group ep_dev_attr_grp = {
0130     .attrs = ep_dev_attrs,
0131 };
0132 static const struct attribute_group *ep_dev_groups[] = {
0133     &ep_dev_attr_grp,
0134     NULL
0135 };
0136
0137 static void ep_device_release(struct device *dev)
0138 {
0139     struct ep_device *ep_dev = to_ep_device(dev);
0140
0141     kfree(ep_dev);
0142 }
0143
0144 struct device_type usb_ep_device_type = {
0145     .name =     "usb_endpoint",
0146     .release = ep_device_release,
0147 };
0148
0149 int usb_create_ep_devs(struct device *parent,
0150             struct usb_host_endpoint *endpoint,
0151             struct usb_device *udev)
0152 {
0153     struct ep_device *ep_dev;
0154     int retval;
0155
0156     ep_dev = kzalloc(sizeof(*ep_dev), GFP_KERNEL);
0157     if (!ep_dev) {
0158         retval = -ENOMEM;
0159         goto exit;
0160     }
0161
0162     ep_dev->desc = &endpoint->desc;
0163     ep_dev->udev = udev;
0164     ep_dev->dev.groups = ep_dev_groups;
0165     ep_dev->dev.type = &usb_ep_device_type;
0166     ep_dev->dev.parent = parent;
0167     dev_set_name(&ep_dev->dev, "ep_%02x", endpoint->desc.bEndpointAddress);
0168
0169     retval = device_register(&ep_dev->dev);
0170     if (retval)
0171         goto error_register;
0172
0173     device_enable_async_suspend(&ep_dev->dev);
0174     endpoint->ep_dev = ep_dev;
0175     return retval;
0176
0177 error_register:
0178     put_device(&ep_dev->dev);
0179 exit:
0180     return retval;
0181 }
0182
0183 void usb_remove_ep_devs(struct usb_host_endpoint *endpoint)
0184 {
0185     struct ep_device *ep_dev = endpoint->ep_dev;
0186
0187     if (ep_dev) {
0188         device_unregister(&ep_dev->dev);
0189         endpoint->ep_dev = NULL;
0190     }
0191 }