drivers/usb/core/endpoint.c

   1 /*
   2  * drivers/usb/core/endpoint.c
   3  *
   4  * (C) Copyright 2002,2004,2006 Greg Kroah-Hartman
   5  * (C) Copyright 2002,2004 IBM Corp.
   6  * (C) Copyright 2006 Novell Inc.
   7  *
   8  * Endpoint sysfs stuff
   9  *
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/usb.h>
  14 #include "usb.h"
  15
  16 /* endpoint stuff */
  17
  18 struct ep_device {
  19         struct usb_endpoint_descriptor *desc;
  20         struct usb_device *udev;
  21         struct device dev;
  22 };
  23 #define to_ep_device(_dev) \
  24         container_of(_dev, struct ep_device, dev)
  25
  26 struct ep_attribute {
  27         struct attribute attr;
  28         ssize_t (*show)(struct usb_device *,
  29                         struct usb_endpoint_descriptor *, char *);
  30 };
  31 #define to_ep_attribute(_attr) \
  32         container_of(_attr, struct ep_attribute, attr)
  33
  34 #define usb_ep_attr(field, format_string)                       \
  35 static ssize_t show_ep_##field(struct device *dev,              \
  36                                struct device_attribute *attr,   \
  37                                char *buf)                       \
  38 {                                                               \
  39         struct ep_device *ep = to_ep_device(dev);               \
  40         return sprintf(buf, format_string, ep->desc->field);    \
  41 }                                                               \
  42 static DEVICE_ATTR(field, S_IRUGO, show_ep_##field, NULL);
  43
  44 usb_ep_attr(bLength, "%02x\n")
  45 usb_ep_attr(bEndpointAddress, "%02x\n")
  46 usb_ep_attr(bmAttributes, "%02x\n")
  47 usb_ep_attr(bInterval, "%02x\n")
  48
  49 static ssize_t show_ep_wMaxPacketSize(struct device *dev,
  50                                       struct device_attribute *attr, char *buf)
  51 {
  52         struct ep_device *ep = to_ep_device(dev);
  53         return sprintf(buf, "%04x\n",
  54                         le16_to_cpu(ep->desc->wMaxPacketSize) & 0x07ff);
  55 }
  56 static DEVICE_ATTR(wMaxPacketSize, S_IRUGO, show_ep_wMaxPacketSize, NULL);
  57
  58 static ssize_t show_ep_type(struct device *dev, struct device_attribute *attr,
  59                             char *buf)
  60 {
  61         struct ep_device *ep = to_ep_device(dev);
  62         char *type = "unknown";
  63
  64         switch (ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
  65         case USB_ENDPOINT_XFER_CONTROL:
  66                 type = "Control";
  67                 break;
  68         case USB_ENDPOINT_XFER_ISOC:
  69                 type = "Isoc";
  70                 break;
  71         case USB_ENDPOINT_XFER_BULK:
  72                 type = "Bulk";
  73                 break;
  74         case USB_ENDPOINT_XFER_INT:
  75                 type = "Interrupt";
  76                 break;
  77         }
  78         return sprintf(buf, "%s\n", type);
  79 }
  80 static DEVICE_ATTR(type, S_IRUGO, show_ep_type, NULL);
  81
  82 static ssize_t show_ep_interval(struct device *dev,
  83                                 struct device_attribute *attr, char *buf)
  84 {
  85         struct ep_device *ep = to_ep_device(dev);
  86         char unit;
  87         unsigned interval = 0;
  88         unsigned in;
  89
  90         in = (ep->desc->bEndpointAddress & USB_DIR_IN);
  91
  92         switch (ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
  93         case USB_ENDPOINT_XFER_CONTROL:
  94                 if (ep->udev->speed == USB_SPEED_HIGH)  /* uframes per NAK */
  95                         interval = ep->desc->bInterval;
  96                 break;
  97         case USB_ENDPOINT_XFER_ISOC:
  98                 interval = 1 << (ep->desc->bInterval - 1);
  99                 break;
 100         case USB_ENDPOINT_XFER_BULK:
 101                 if (ep->udev->speed == USB_SPEED_HIGH && !in) /* uframes per NAK */
 102                         interval = ep->desc->bInterval;
 103                 break;
 104         case USB_ENDPOINT_XFER_INT:
 105                 if (ep->udev->speed == USB_SPEED_HIGH)
 106                         interval = 1 << (ep->desc->bInterval - 1);
 107                 else
 108                         interval = ep->desc->bInterval;
 109                 break;
 110         }
 111         interval *= (ep->udev->speed == USB_SPEED_HIGH) ? 125 : 1000;
 112         if (interval % 1000)
 113                 unit = 'u';
 114         else {
 115                 unit = 'm';
 116                 interval /= 1000;
 117         }
 118
 119         return sprintf(buf, "%d%cs\n", interval, unit);
 120 }
 121 static DEVICE_ATTR(interval, S_IRUGO, show_ep_interval, NULL);
 122
 123 static ssize_t show_ep_direction(struct device *dev,
 124                                  struct device_attribute *attr, char *buf)
 125 {
 126         struct ep_device *ep = to_ep_device(dev);
 127         char *direction;
 128
 129         if ((ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
 130                         USB_ENDPOINT_XFER_CONTROL)
 131                 direction = "both";
 132         else if (ep->desc->bEndpointAddress & USB_DIR_IN)
 133                 direction = "in";
 134         else
 135                 direction = "out";
 136         return sprintf(buf, "%s\n", direction);
 137 }
 138 static DEVICE_ATTR(direction, S_IRUGO, show_ep_direction, NULL);
 139
 140 static struct attribute *ep_dev_attrs[] = {
 141         &dev_attr_bLength.attr,
 142         &dev_attr_bEndpointAddress.attr,
 143         &dev_attr_bmAttributes.attr,
 144         &dev_attr_bInterval.attr,
 145         &dev_attr_wMaxPacketSize.attr,
 146         &dev_attr_interval.attr,
 147         &dev_attr_type.attr,
 148         &dev_attr_direction.attr,
 149         NULL,
 150 };
 151 static struct attribute_group ep_dev_attr_grp = {
 152         .attrs = ep_dev_attrs,
 153 };
 154
 155 static struct endpoint_class {
 156         struct kref kref;
 157         struct class *class;
 158 } *ep_class;
 159
 160 static int init_endpoint_class(void)
 161 {
 162         int result = 0;
 163
 164         if (ep_class != NULL) {
 165                 kref_get(&ep_class->kref);
 166                 goto exit;
 167         }
 168
 169         ep_class = kmalloc(sizeof(*ep_class), GFP_KERNEL);
 170         if (!ep_class) {
 171                 result = -ENOMEM;
 172                 goto exit;
 173         }
 174
 175         kref_init(&ep_class->kref);
 176         ep_class->class = class_create(THIS_MODULE, "usb_endpoint");
 177         if (IS_ERR(ep_class->class)) {
 178                 result = IS_ERR(ep_class->class);
 179                 kfree(ep_class);
 180                 ep_class = NULL;
 181                 goto exit;
 182         }
 183
 184 exit:
 185         return result;
 186 }
 187
 188 static void release_endpoint_class(struct kref *kref)
 189 {
 190         /* Ok, we cheat as we know we only have one ep_class */
 191         class_destroy(ep_class->class);
 192         kfree(ep_class);
 193         ep_class = NULL;
 194 }
 195
 196 static void destroy_endpoint_class(void)
 197 {
 198         if (ep_class)
 199                 kref_put(&ep_class->kref, release_endpoint_class);
 200 }
 201
 202 static void ep_device_release(struct device *dev)
 203 {
 204         struct ep_device *ep_dev = to_ep_device(dev);
 205
 206         dev_dbg(dev, "%s called for %s\n", __FUNCTION__, dev->bus_id);
 207         kfree(ep_dev);
 208 }
 209
 210 int usb_create_ep_files(struct device *parent,
 211                         struct usb_host_endpoint *endpoint,
 212                         struct usb_device *udev)
 213 {
 214         char name[8];
 215         struct ep_device *ep_dev;
 216         int minor;
 217         int retval;
 218
 219         retval = init_endpoint_class();
 220         if (retval)
 221                 goto exit;
 222
 223         ep_dev = kzalloc(sizeof(*ep_dev), GFP_KERNEL);
 224         if (!ep_dev) {
 225                 retval = -ENOMEM;
 226                 goto error_alloc;
 227         }
 228
 229         /* fun calculation to determine the minor of this endpoint */
 230         minor = (((udev->bus->busnum - 1) * 128) * 16) + (udev->devnum - 1);
 231
 232         ep_dev->desc = &endpoint->desc;
 233         ep_dev->udev = udev;
 234         ep_dev->dev.devt = MKDEV(442, minor);   // FIXME fake number...
 235         ep_dev->dev.class = ep_class->class;
 236         ep_dev->dev.parent = parent;
 237         ep_dev->dev.release = ep_device_release;
 238         snprintf(ep_dev->dev.bus_id, BUS_ID_SIZE, "usbdev%d.%d_ep%02x",
 239                  udev->bus->busnum, udev->devnum,
 240                  endpoint->desc.bEndpointAddress);
 241
 242         retval = device_register(&ep_dev->dev);
 243         if (retval)
 244                 goto error_register;
 245         retval = sysfs_create_group(&ep_dev->dev.kobj, &ep_dev_attr_grp);
 246         if (retval)
 247                 goto error_group;
 248
 249         /* create the symlink to the old-style "ep_XX" directory */
 250         sprintf(name, "ep_%02x", endpoint->desc.bEndpointAddress);
 251         retval = sysfs_create_link(&parent->kobj, &ep_dev->dev.kobj, name);
 252         if (retval)
 253                 goto error_link;
 254         endpoint->ep_dev = ep_dev;
 255         return retval;
 256
 257 error_link:
 258         sysfs_remove_group(&ep_dev->dev.kobj, &ep_dev_attr_grp);
 259 error_group:
 260         device_unregister(&ep_dev->dev);
 261         destroy_endpoint_class();
 262         return retval;
 263
 264 error_register:
 265         kfree(ep_dev);
 266 error_alloc:
 267         destroy_endpoint_class();
 268 exit:
 269         return retval;
 270 }
 271
 272 void usb_remove_ep_files(struct usb_host_endpoint *endpoint)
 273 {
 274
 275         if (endpoint->ep_dev) {
 276                 char name[8];
 277
 278                 sprintf(name, "ep_%02x", endpoint->desc.bEndpointAddress);
 279                 sysfs_remove_link(&endpoint->ep_dev->dev.parent->kobj, name);
 280                 sysfs_remove_group(&endpoint->ep_dev->dev.kobj, &ep_dev_attr_grp);
 281                 device_unregister(&endpoint->ep_dev->dev);
 282                 endpoint->ep_dev = NULL;
 283                 destroy_endpoint_class();
 284         }
 285 }