diff options
| -rw-r--r-- | drivers/usb/core/endpoint.c | 98 |
1 files changed, 85 insertions, 13 deletions
diff --git a/drivers/usb/core/endpoint.c b/drivers/usb/core/endpoint.c index 3b2d137912be..c505b767cee1 100644 --- a/drivers/usb/core/endpoint.c +++ b/drivers/usb/core/endpoint.c @@ -10,15 +10,20 @@ */ #include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/idr.h> #include <linux/usb.h> #include "usb.h" -/* endpoint stuff */ +#define MAX_ENDPOINT_MINORS (64*128*32) +static int usb_endpoint_major; +static DEFINE_IDR(endpoint_idr); struct ep_device { struct usb_endpoint_descriptor *desc; struct usb_device *udev; struct device dev; + int minor; }; #define to_ep_device(_dev) \ container_of(_dev, struct ep_device, dev) @@ -152,6 +157,55 @@ static struct attribute_group ep_dev_attr_grp = { .attrs = ep_dev_attrs, }; +static int usb_endpoint_major_init(void) +{ + dev_t dev; + int error; + + error = alloc_chrdev_region(&dev, 0, MAX_ENDPOINT_MINORS, + "usb_endpoint"); + if (error) { + err("unable to get a dynamic major for usb endpoints"); + return error; + } + usb_endpoint_major = MAJOR(dev); + + return error; +} + +static void usb_endpoint_major_cleanup(void) +{ + unregister_chrdev_region(MKDEV(usb_endpoint_major, 0), + MAX_ENDPOINT_MINORS); +} + +static int endpoint_get_minor(struct ep_device *ep_dev) +{ + static DEFINE_MUTEX(minor_lock); + int retval = -ENOMEM; + int id; + + mutex_lock(&minor_lock); + if (idr_pre_get(&endpoint_idr, GFP_KERNEL) == 0) + goto exit; + + retval = idr_get_new(&endpoint_idr, ep_dev, &id); + if (retval < 0) { + if (retval == -EAGAIN) + retval = -ENOMEM; + goto exit; + } + ep_dev->minor = id & MAX_ID_MASK; +exit: + mutex_unlock(&minor_lock); + return retval; +} + +static void endpoint_free_minor(struct ep_device *ep_dev) +{ + idr_remove(&endpoint_idr, ep_dev->minor); +} + static struct endpoint_class { struct kref kref; struct class *class; @@ -176,11 +230,20 @@ static int init_endpoint_class(void) 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; + goto class_create_error; } + result = usb_endpoint_major_init(); + if (result) + goto endpoint_major_error; + + goto exit; + +endpoint_major_error: + class_destroy(ep_class->class); +class_create_error: + kfree(ep_class); + ep_class = NULL; exit: return result; } @@ -191,6 +254,7 @@ static void release_endpoint_class(struct kref *kref) class_destroy(ep_class->class); kfree(ep_class); ep_class = NULL; + usb_endpoint_major_cleanup(); } static void destroy_endpoint_class(void) @@ -213,7 +277,6 @@ int usb_create_ep_files(struct device *parent, { char name[8]; struct ep_device *ep_dev; - int minor; int retval; retval = init_endpoint_class(); @@ -226,12 +289,16 @@ int usb_create_ep_files(struct device *parent, goto error_alloc; } - /* fun calculation to determine the minor of this endpoint */ - minor = (((udev->bus->busnum - 1) * 128) * 16) + (udev->devnum - 1); + retval = endpoint_get_minor(ep_dev); + if (retval) { + dev_err(parent, "can not allocate minor number for %s", + ep_dev->dev.bus_id); + goto error_register; + } ep_dev->desc = &endpoint->desc; ep_dev->udev = udev; - ep_dev->dev.devt = MKDEV(442, minor); // FIXME fake number... + ep_dev->dev.devt = MKDEV(usb_endpoint_major, ep_dev->minor); ep_dev->dev.class = ep_class->class; ep_dev->dev.parent = parent; ep_dev->dev.release = ep_device_release; @@ -241,7 +308,7 @@ int usb_create_ep_files(struct device *parent, retval = device_register(&ep_dev->dev); if (retval) - goto error_register; + goto error_chrdev; retval = sysfs_create_group(&ep_dev->dev.kobj, &ep_dev_attr_grp); if (retval) goto error_group; @@ -261,6 +328,9 @@ error_group: destroy_endpoint_class(); return retval; +error_chrdev: + endpoint_free_minor(ep_dev); + error_register: kfree(ep_dev); error_alloc: @@ -271,14 +341,16 @@ exit: void usb_remove_ep_files(struct usb_host_endpoint *endpoint) { + struct ep_device *ep_dev = endpoint->ep_dev; - if (endpoint->ep_dev) { + if (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); + sysfs_remove_link(&ep_dev->dev.parent->kobj, name); + sysfs_remove_group(&ep_dev->dev.kobj, &ep_dev_attr_grp); + endpoint_free_minor(ep_dev); + device_unregister(&ep_dev->dev); endpoint->ep_dev = NULL; destroy_endpoint_class(); } |