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path: root/drivers/usb/usb-skeleton.c
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Diffstat (limited to 'drivers/usb/usb-skeleton.c')
-rw-r--r--drivers/usb/usb-skeleton.c145
1 files changed, 49 insertions, 96 deletions
diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c
index b1e579c5c97..545d09b8081 100644
--- a/drivers/usb/usb-skeleton.c
+++ b/drivers/usb/usb-skeleton.c
@@ -14,7 +14,6 @@
#include <linux/kernel.h>
#include <linux/errno.h>
-#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
@@ -28,7 +27,7 @@
#define USB_SKEL_PRODUCT_ID 0xfff0
/* table of devices that work with this driver */
-static struct usb_device_id skel_table[] = {
+static const struct usb_device_id skel_table[] = {
{ USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
{ } /* Terminating entry */
};
@@ -60,13 +59,11 @@ struct usb_skel {
__u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
__u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
int errors; /* the last request tanked */
- int open_count; /* count the number of openers */
bool ongoing_read; /* a read is going on */
- bool processed_urb; /* indicates we haven't processed the urb */
spinlock_t err_lock; /* lock for errors */
struct kref kref;
struct mutex io_mutex; /* synchronize I/O with disconnect */
- struct completion bulk_in_completion; /* to wait for an ongoing read */
+ wait_queue_head_t bulk_in_wait; /* to wait for an ongoing read */
};
#define to_skel_dev(d) container_of(d, struct usb_skel, kref)
@@ -94,8 +91,8 @@ static int skel_open(struct inode *inode, struct file *file)
interface = usb_find_interface(&skel_driver, subminor);
if (!interface) {
- err("%s - error, can't find device for minor %d",
- __func__, subminor);
+ pr_err("%s - error, can't find device for minor %d\n",
+ __func__, subminor);
retval = -ENODEV;
goto exit;
}
@@ -106,33 +103,15 @@ static int skel_open(struct inode *inode, struct file *file)
goto exit;
}
+ retval = usb_autopm_get_interface(interface);
+ if (retval)
+ goto exit;
+
/* increment our usage count for the device */
kref_get(&dev->kref);
- /* lock the device to allow correctly handling errors
- * in resumption */
- mutex_lock(&dev->io_mutex);
-
- if (!dev->open_count++) {
- retval = usb_autopm_get_interface(interface);
- if (retval) {
- dev->open_count--;
- mutex_unlock(&dev->io_mutex);
- kref_put(&dev->kref, skel_delete);
- goto exit;
- }
- } /* else { //uncomment this block if you want exclusive open
- retval = -EBUSY;
- dev->open_count--;
- mutex_unlock(&dev->io_mutex);
- kref_put(&dev->kref, skel_delete);
- goto exit;
- } */
- /* prevent the device from being autosuspended */
-
/* save our object in the file's private structure */
file->private_data = dev;
- mutex_unlock(&dev->io_mutex);
exit:
return retval;
@@ -142,13 +121,13 @@ static int skel_release(struct inode *inode, struct file *file)
{
struct usb_skel *dev;
- dev = (struct usb_skel *)file->private_data;
+ dev = file->private_data;
if (dev == NULL)
return -ENODEV;
/* allow the device to be autosuspended */
mutex_lock(&dev->io_mutex);
- if (!--dev->open_count && dev->interface)
+ if (dev->interface)
usb_autopm_put_interface(dev->interface);
mutex_unlock(&dev->io_mutex);
@@ -162,7 +141,7 @@ static int skel_flush(struct file *file, fl_owner_t id)
struct usb_skel *dev;
int res;
- dev = (struct usb_skel *)file->private_data;
+ dev = file->private_data;
if (dev == NULL)
return -ENODEV;
@@ -193,8 +172,9 @@ static void skel_read_bulk_callback(struct urb *urb)
if (!(urb->status == -ENOENT ||
urb->status == -ECONNRESET ||
urb->status == -ESHUTDOWN))
- err("%s - nonzero write bulk status received: %d",
- __func__, urb->status);
+ dev_err(&dev->interface->dev,
+ "%s - nonzero write bulk status received: %d\n",
+ __func__, urb->status);
dev->errors = urb->status;
} else {
@@ -203,7 +183,7 @@ static void skel_read_bulk_callback(struct urb *urb)
dev->ongoing_read = 0;
spin_unlock(&dev->err_lock);
- complete(&dev->bulk_in_completion);
+ wake_up_interruptible(&dev->bulk_in_wait);
}
static int skel_do_read_io(struct usb_skel *dev, size_t count)
@@ -224,12 +204,16 @@ static int skel_do_read_io(struct usb_skel *dev, size_t count)
dev->ongoing_read = 1;
spin_unlock_irq(&dev->err_lock);
+ /* submit bulk in urb, which means no data to deliver */
+ dev->bulk_in_filled = 0;
+ dev->bulk_in_copied = 0;
+
/* do it */
rv = usb_submit_urb(dev->bulk_in_urb, GFP_KERNEL);
if (rv < 0) {
- err("%s - failed submitting read urb, error %d",
+ dev_err(&dev->interface->dev,
+ "%s - failed submitting read urb, error %d\n",
__func__, rv);
- dev->bulk_in_filled = 0;
rv = (rv == -ENOMEM) ? rv : -EIO;
spin_lock_irq(&dev->err_lock);
dev->ongoing_read = 0;
@@ -246,7 +230,7 @@ static ssize_t skel_read(struct file *file, char *buffer, size_t count,
int rv;
bool ongoing_io;
- dev = (struct usb_skel *)file->private_data;
+ dev = file->private_data;
/* if we cannot read at all, return EOF */
if (!dev->bulk_in_urb || !count)
@@ -278,25 +262,9 @@ retry:
* IO may take forever
* hence wait in an interruptible state
*/
- rv = wait_for_completion_interruptible(&dev->bulk_in_completion);
+ rv = wait_event_interruptible(dev->bulk_in_wait, (!dev->ongoing_read));
if (rv < 0)
goto exit;
- /*
- * by waiting we also semiprocessed the urb
- * we must finish now
- */
- dev->bulk_in_copied = 0;
- dev->processed_urb = 1;
- }
-
- if (!dev->processed_urb) {
- /*
- * the URB hasn't been processed
- * do it now
- */
- wait_for_completion(&dev->bulk_in_completion);
- dev->bulk_in_copied = 0;
- dev->processed_urb = 1;
}
/* errors must be reported */
@@ -306,8 +274,6 @@ retry:
dev->errors = 0;
/* to preserve notifications about reset */
rv = (rv == -EPIPE) ? rv : -EIO;
- /* no data to deliver */
- dev->bulk_in_filled = 0;
/* report it */
goto exit;
}
@@ -358,9 +324,8 @@ retry:
rv = skel_do_read_io(dev, count);
if (rv < 0)
goto exit;
- else if (!(file->f_flags & O_NONBLOCK))
+ else
goto retry;
- rv = -EAGAIN;
}
exit:
mutex_unlock(&dev->io_mutex);
@@ -378,8 +343,9 @@ static void skel_write_bulk_callback(struct urb *urb)
if (!(urb->status == -ENOENT ||
urb->status == -ECONNRESET ||
urb->status == -ESHUTDOWN))
- err("%s - nonzero write bulk status received: %d",
- __func__, urb->status);
+ dev_err(&dev->interface->dev,
+ "%s - nonzero write bulk status received: %d\n",
+ __func__, urb->status);
spin_lock(&dev->err_lock);
dev->errors = urb->status;
@@ -387,8 +353,8 @@ static void skel_write_bulk_callback(struct urb *urb)
}
/* free up our allocated buffer */
- usb_buffer_free(urb->dev, urb->transfer_buffer_length,
- urb->transfer_buffer, urb->transfer_dma);
+ usb_free_coherent(urb->dev, urb->transfer_buffer_length,
+ urb->transfer_buffer, urb->transfer_dma);
up(&dev->limit_sem);
}
@@ -401,7 +367,7 @@ static ssize_t skel_write(struct file *file, const char *user_buffer,
char *buf = NULL;
size_t writesize = min(count, (size_t)MAX_TRANSFER);
- dev = (struct usb_skel *)file->private_data;
+ dev = file->private_data;
/* verify that we actually have some data to write */
if (count == 0)
@@ -442,8 +408,8 @@ static ssize_t skel_write(struct file *file, const char *user_buffer,
goto error;
}
- buf = usb_buffer_alloc(dev->udev, writesize, GFP_KERNEL,
- &urb->transfer_dma);
+ buf = usb_alloc_coherent(dev->udev, writesize, GFP_KERNEL,
+ &urb->transfer_dma);
if (!buf) {
retval = -ENOMEM;
goto error;
@@ -473,8 +439,9 @@ static ssize_t skel_write(struct file *file, const char *user_buffer,
retval = usb_submit_urb(urb, GFP_KERNEL);
mutex_unlock(&dev->io_mutex);
if (retval) {
- err("%s - failed submitting write urb, error %d", __func__,
- retval);
+ dev_err(&dev->interface->dev,
+ "%s - failed submitting write urb, error %d\n",
+ __func__, retval);
goto error_unanchor;
}
@@ -491,7 +458,7 @@ error_unanchor:
usb_unanchor_urb(urb);
error:
if (urb) {
- usb_buffer_free(dev->udev, writesize, buf, urb->transfer_dma);
+ usb_free_coherent(dev->udev, writesize, buf, urb->transfer_dma);
usb_free_urb(urb);
}
up(&dev->limit_sem);
@@ -507,6 +474,7 @@ static const struct file_operations skel_fops = {
.open = skel_open,
.release = skel_release,
.flush = skel_flush,
+ .llseek = noop_llseek,
};
/*
@@ -532,7 +500,7 @@ static int skel_probe(struct usb_interface *interface,
/* allocate memory for our device state and initialize it */
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev) {
- err("Out of memory");
+ dev_err(&interface->dev, "Out of memory\n");
goto error;
}
kref_init(&dev->kref);
@@ -540,7 +508,7 @@ static int skel_probe(struct usb_interface *interface,
mutex_init(&dev->io_mutex);
spin_lock_init(&dev->err_lock);
init_usb_anchor(&dev->submitted);
- init_completion(&dev->bulk_in_completion);
+ init_waitqueue_head(&dev->bulk_in_wait);
dev->udev = usb_get_dev(interface_to_usbdev(interface));
dev->interface = interface;
@@ -554,17 +522,19 @@ static int skel_probe(struct usb_interface *interface,
if (!dev->bulk_in_endpointAddr &&
usb_endpoint_is_bulk_in(endpoint)) {
/* we found a bulk in endpoint */
- buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
+ buffer_size = usb_endpoint_maxp(endpoint);
dev->bulk_in_size = buffer_size;
dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
if (!dev->bulk_in_buffer) {
- err("Could not allocate bulk_in_buffer");
+ dev_err(&interface->dev,
+ "Could not allocate bulk_in_buffer\n");
goto error;
}
dev->bulk_in_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!dev->bulk_in_urb) {
- err("Could not allocate bulk_in_urb");
+ dev_err(&interface->dev,
+ "Could not allocate bulk_in_urb\n");
goto error;
}
}
@@ -576,7 +546,8 @@ static int skel_probe(struct usb_interface *interface,
}
}
if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
- err("Could not find both bulk-in and bulk-out endpoints");
+ dev_err(&interface->dev,
+ "Could not find both bulk-in and bulk-out endpoints\n");
goto error;
}
@@ -587,7 +558,8 @@ static int skel_probe(struct usb_interface *interface,
retval = usb_register_dev(interface, &skel_class);
if (retval) {
/* something prevented us from registering this driver */
- err("Not able to get a minor for this device.");
+ dev_err(&interface->dev,
+ "Not able to get a minor for this device.\n");
usb_set_intfdata(interface, NULL);
goto error;
}
@@ -687,25 +659,6 @@ static struct usb_driver skel_driver = {
.supports_autosuspend = 1,
};
-static int __init usb_skel_init(void)
-{
- int result;
-
- /* register this driver with the USB subsystem */
- result = usb_register(&skel_driver);
- if (result)
- err("usb_register failed. Error number %d", result);
-
- return result;
-}
-
-static void __exit usb_skel_exit(void)
-{
- /* deregister this driver with the USB subsystem */
- usb_deregister(&skel_driver);
-}
-
-module_init(usb_skel_init);
-module_exit(usb_skel_exit);
+module_usb_driver(skel_driver);
MODULE_LICENSE("GPL");