[PATCH] USB: make endpoints real struct devices

This will allow for us to give endpoints a major/minor to create a
"usbfs2-like" way to access endpoints directly from userspace in an
easier manner than the current usbfs provides us.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 150 insertions, 88 deletions

diff --git a/drivers/usb/core/endpoint.c b/drivers/usb/core/endpoint.c
index 4c2fe8f723e5..247b5a4913a8 100644
--- a/drivers/usb/core/endpoint.c
+++ b/drivers/usb/core/endpoint.c
@@ -14,13 +14,14 @@
 #include "usb.h"
 
 /* endpoint stuff */
-struct ep_object {
+
+struct ep_device {
         struct usb_endpoint_descriptor *desc;
         struct usb_device *udev;
-        struct kobject kobj;
+        struct device dev;
 };
-#define to_ep_object(_kobj) \
-        container_of(_kobj, struct ep_object, kobj)
+#define to_ep_device(_dev) \
+        container_of(_dev, struct ep_device, dev)
 
 struct ep_attribute {
         struct attribute attr;
@@ -30,40 +31,37 @@ struct ep_attribute {
 #define to_ep_attribute(_attr) \
         container_of(_attr, struct ep_attribute, attr)
 
-#define EP_ATTR(_name)                                          \
-struct ep_attribute ep_##_name = {                              \
-        .attr = {.name = #_name, .owner = THIS_MODULE,          \
-                        .mode = S_IRUGO},                       \
-        .show = show_ep_##_name}
-
 #define usb_ep_attr(field, format_string)                       \
-static ssize_t show_ep_##field(struct usb_device *udev,         \
-                struct usb_endpoint_descriptor *desc,           \
-                char *buf)                                      \
+static ssize_t show_ep_##field(struct device *dev,              \
+                               struct device_attribute *attr,   \
+                               char *buf)                       \
 {                                                               \
-        return sprintf(buf, format_string, desc->field);        \
+        struct ep_device *ep = to_ep_device(dev);               \
+        return sprintf(buf, format_string, ep->desc->field);    \
 }                                                               \
-static EP_ATTR(field);
+static DEVICE_ATTR(field, S_IRUGO, show_ep_##field, NULL);
 
 usb_ep_attr(bLength, "%02x\n")
 usb_ep_attr(bEndpointAddress, "%02x\n")
 usb_ep_attr(bmAttributes, "%02x\n")
 usb_ep_attr(bInterval, "%02x\n")
 
-static ssize_t show_ep_wMaxPacketSize(struct usb_device *udev,
-                struct usb_endpoint_descriptor *desc, char *buf)
+static ssize_t show_ep_wMaxPacketSize(struct device *dev,
+                                      struct device_attribute *attr, char *buf)
 {
+        struct ep_device *ep = to_ep_device(dev);
         return sprintf(buf, "%04x\n",
-                        le16_to_cpu(desc->wMaxPacketSize) & 0x07ff);
+                        le16_to_cpu(ep->desc->wMaxPacketSize) & 0x07ff);
 }
-static EP_ATTR(wMaxPacketSize);
+static DEVICE_ATTR(wMaxPacketSize, S_IRUGO, show_ep_wMaxPacketSize, NULL);
 
-static ssize_t show_ep_type(struct usb_device *udev,
-                struct usb_endpoint_descriptor *desc, char *buf)
+static ssize_t show_ep_type(struct device *dev, struct device_attribute *attr,
+                            char *buf)
 {
+        struct ep_device *ep = to_ep_device(dev);
         char *type = "unknown";
 
-        switch (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
+        switch (ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
         case USB_ENDPOINT_XFER_CONTROL:
                 type = "Control";
                 break;
@@ -79,37 +77,38 @@ static ssize_t show_ep_type(struct usb_device *udev,
         }
         return sprintf(buf, "%s\n", type);
 }
-static EP_ATTR(type);
+static DEVICE_ATTR(type, S_IRUGO, show_ep_type, NULL);
 
-static ssize_t show_ep_interval(struct usb_device *udev,
-                struct usb_endpoint_descriptor *desc, char *buf)
+static ssize_t show_ep_interval(struct device *dev,
+                                struct device_attribute *attr, char *buf)
 {
+        struct ep_device *ep = to_ep_device(dev);
         char unit;
         unsigned interval = 0;
         unsigned in;
 
-        in = (desc->bEndpointAddress & USB_DIR_IN);
+        in = (ep->desc->bEndpointAddress & USB_DIR_IN);
 
-        switch (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
+        switch (ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
         case USB_ENDPOINT_XFER_CONTROL:
-                if (udev->speed == USB_SPEED_HIGH)      /* uframes per NAK */
-                        interval = desc->bInterval;
+                if (ep->udev->speed == USB_SPEED_HIGH)  /* uframes per NAK */
+                        interval = ep->desc->bInterval;
                 break;
         case USB_ENDPOINT_XFER_ISOC:
-                interval = 1 << (desc->bInterval - 1);
+                interval = 1 << (ep->desc->bInterval - 1);
                 break;
         case USB_ENDPOINT_XFER_BULK:
-                if (udev->speed == USB_SPEED_HIGH && !in) /* uframes per NAK */
-                        interval = desc->bInterval;
+                if (ep->udev->speed == USB_SPEED_HIGH && !in) /* uframes per NAK */
+                        interval = ep->desc->bInterval;
                 break;
         case USB_ENDPOINT_XFER_INT:
-                if (udev->speed == USB_SPEED_HIGH)
-                        interval = 1 << (desc->bInterval - 1);
+                if (ep->udev->speed == USB_SPEED_HIGH)
+                        interval = 1 << (ep->desc->bInterval - 1);
                 else
-                        interval = desc->bInterval;
+                        interval = ep->desc->bInterval;
                 break;
         }
-        interval *= (udev->speed == USB_SPEED_HIGH) ? 125 : 1000;
+        interval *= (ep->udev->speed == USB_SPEED_HIGH) ? 125 : 1000;
         if (interval % 1000)
                 unit = 'u';
         else {
@@ -119,95 +118,158 @@ static ssize_t show_ep_interval(struct usb_device *udev,
 
         return sprintf(buf, "%d%cs\n", interval, unit);
 }
-static EP_ATTR(interval);
+static DEVICE_ATTR(interval, S_IRUGO, show_ep_interval, NULL);
 
-static ssize_t show_ep_direction(struct usb_device *udev,
-                struct usb_endpoint_descriptor *desc, char *buf)
+static ssize_t show_ep_direction(struct device *dev,
+                                 struct device_attribute *attr, char *buf)
 {
+        struct ep_device *ep = to_ep_device(dev);
         char *direction;
 
-        if ((desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
+        if ((ep->desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
                         USB_ENDPOINT_XFER_CONTROL)
                 direction = "both";
-        else if (desc->bEndpointAddress & USB_DIR_IN)
+        else if (ep->desc->bEndpointAddress & USB_DIR_IN)
                 direction = "in";
         else
                 direction = "out";
         return sprintf(buf, "%s\n", direction);
 }
-static EP_ATTR(direction);
-
-static struct attribute *ep_attrs[] = {
-        &ep_bLength.attr,
-        &ep_bEndpointAddress.attr,
-        &ep_bmAttributes.attr,
-        &ep_bInterval.attr,
-        &ep_wMaxPacketSize.attr,
-        &ep_type.attr,
-        &ep_interval.attr,
-        &ep_direction.attr,
+static DEVICE_ATTR(direction, S_IRUGO, show_ep_direction, NULL);
+
+static struct attribute *ep_dev_attrs[] = {
+        &dev_attr_bLength.attr,
+        &dev_attr_bEndpointAddress.attr,
+        &dev_attr_bmAttributes.attr,
+        &dev_attr_bInterval.attr,
+        &dev_attr_wMaxPacketSize.attr,
+        &dev_attr_interval.attr,
+        &dev_attr_type.attr,
+        &dev_attr_direction.attr,
         NULL,
 };
+static struct attribute_group ep_dev_attr_grp = {
+        .attrs = ep_dev_attrs,
+};
 
-static void ep_object_release(struct kobject *kobj)
+static struct endpoint_class {
+        struct kref kref;
+        struct class *class;
+} *ep_class;
+
+static int init_endpoint_class(void)
 {
-        kfree(to_ep_object(kobj));
+        int result = 0;
+
+        if (ep_class != NULL) {
+                kref_get(&ep_class->kref);
+                goto exit;
+        }
+
+        ep_class = kmalloc(sizeof(*ep_class), GFP_KERNEL);
+        if (!ep_class) {
+                result = -ENOMEM;
+                goto exit;
+        }
+
+        kref_init(&ep_class->kref);
+        ep_class->class = class_create(THIS_MODULE, "usb_endpoint");
+        if (IS_ERR(ep_class->class)) {
+                result = IS_ERR(ep_class->class);
+                kfree(ep_class);
+                ep_class = NULL;
+                goto exit;
+        }
+
+exit:
+        return result;
 }
 
-static ssize_t ep_object_show(struct kobject *kobj, struct attribute *attr,
-                char *buf)
+static void release_endpoint_class(struct kref *kref)
 {
-        struct ep_object *ep_obj = to_ep_object(kobj);
-        struct ep_attribute *ep_attr = to_ep_attribute(attr);
+        /* Ok, we cheat as we know we only have one ep_class */
+        class_destroy(ep_class->class);
+        kfree(ep_class);
+        ep_class = NULL;
+}
 
-        return (ep_attr->show)(ep_obj->udev, ep_obj->desc, buf);
+static void destroy_endpoint_class(void)
+{
+        if (ep_class)
+                kref_put(&ep_class->kref, release_endpoint_class);
 }
 
-static struct sysfs_ops ep_object_sysfs_ops = {
-        .show =                 ep_object_show,
-};
+static void ep_device_release(struct device *dev)
+{
+        struct ep_device *ep_dev = to_ep_device(dev);
 
-static struct kobj_type ep_object_ktype = {
-        .release =              ep_object_release,
-        .sysfs_ops =            &ep_object_sysfs_ops,
-        .default_attrs =        ep_attrs,
-};
+        dev_dbg(dev, "%s called for %s\n", __FUNCTION__, dev->bus_id);
+        kfree(ep_dev);
+}
 
 void usb_create_ep_files(struct device *parent,
                          struct usb_host_endpoint *endpoint,
                          struct usb_device *udev)
 {
-        struct ep_object *ep_obj;
-        struct kobject *kobj;
+        char name[8];
+        struct ep_device *ep_dev;
+        int minor;
+        int retval;
+
+        retval = init_endpoint_class();
+        if (retval)
+                goto exit;
 
-        ep_obj = kzalloc(sizeof(struct ep_object), GFP_KERNEL);
-        if (!ep_obj)
-                return;
+        ep_dev = kzalloc(sizeof(*ep_dev), GFP_KERNEL);
+        if (!ep_dev) {
+                retval = -ENOMEM;
+                goto exit;
+        }
 
-        ep_obj->desc = &endpoint->desc;
-        ep_obj->udev = udev;
+        /* fun calculation to determine the minor of this endpoint */
+        minor = (((udev->bus->busnum - 1) * 128) * 16) + (udev->devnum - 1);
 
-        kobj = &ep_obj->kobj;
-        kobject_set_name(kobj, "ep_%02x", endpoint->desc.bEndpointAddress);
-        kobj->parent = &parent->kobj;
-        kobj->ktype = &ep_object_ktype;
+        ep_dev->desc = &endpoint->desc;
+        ep_dev->udev = udev;
+        ep_dev->dev.devt = MKDEV(442, minor);   // FIXME fake number...
+        ep_dev->dev.class = ep_class->class;
+        ep_dev->dev.parent = parent;
+        ep_dev->dev.release = ep_device_release;
+        snprintf(ep_dev->dev.bus_id, BUS_ID_SIZE, "usbdev%d.%d_ep%02x",
+                 udev->bus->busnum, udev->devnum,
+                 endpoint->desc.bEndpointAddress);
 
-        /* Don't use kobject_register, because it generates a hotplug event */
-        kobject_init(kobj);
-        if (kobject_add(kobj) == 0)
-                endpoint->kobj = kobj;
-        else
-                kobject_put(kobj);
+        retval = device_register(&ep_dev->dev);
+        if (retval)
+                goto error;
+        sysfs_create_group(&ep_dev->dev.kobj, &ep_dev_attr_grp);
+
+        endpoint->ep_dev = ep_dev;
+
+        /* create the symlink to the old-style "ep_XX" directory */
+        sprintf(name, "ep_%02x", endpoint->desc.bEndpointAddress);
+        sysfs_create_link(&parent->kobj, &endpoint->ep_dev->dev.kobj, name);
+
+exit:
+        return;
+error:
+        kfree(ep_dev);
+        return;
 }
 
 void usb_remove_ep_files(struct usb_host_endpoint *endpoint)
 {
 
-        if (endpoint->kobj) {
-                kobject_del(endpoint->kobj);
-                kobject_put(endpoint->kobj);
-                endpoint->kobj = NULL;
+        if (endpoint->ep_dev) {
+                char name[8];
+
+                sprintf(name, "ep_%02x", endpoint->desc.bEndpointAddress);
+                sysfs_remove_link(&endpoint->ep_dev->dev.parent->kobj, name);
+                sysfs_remove_group(&endpoint->ep_dev->dev.kobj, &ep_dev_attr_grp);
+                device_unregister(&endpoint->ep_dev->dev);
+                endpoint->ep_dev = NULL;
         }
+        destroy_endpoint_class();
 }