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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/usb-skeleton.c
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Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/usb/usb-skeleton.c')
-rw-r--r--drivers/usb/usb-skeleton.c360
1 files changed, 360 insertions, 0 deletions
diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c
new file mode 100644
index 0000000..6051a64
--- /dev/null
+++ b/drivers/usb/usb-skeleton.c
@@ -0,0 +1,360 @@
+/*
+ * USB Skeleton driver - 2.0
+ *
+ * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2.
+ *
+ * This driver is based on the 2.6.3 version of drivers/usb/usb-skeleton.c
+ * but has been rewritten to be easy to read and use, as no locks are now
+ * needed anymore.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kref.h>
+#include <asm/uaccess.h>
+#include <linux/usb.h>
+
+
+/* Define these values to match your devices */
+#define USB_SKEL_VENDOR_ID 0xfff0
+#define USB_SKEL_PRODUCT_ID 0xfff0
+
+/* table of devices that work with this driver */
+static struct usb_device_id skel_table [] = {
+ { USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
+ { } /* Terminating entry */
+};
+MODULE_DEVICE_TABLE (usb, skel_table);
+
+
+/* Get a minor range for your devices from the usb maintainer */
+#define USB_SKEL_MINOR_BASE 192
+
+/* Structure to hold all of our device specific stuff */
+struct usb_skel {
+ struct usb_device * udev; /* the usb device for this device */
+ struct usb_interface * interface; /* the interface for this device */
+ unsigned char * bulk_in_buffer; /* the buffer to receive data */
+ size_t bulk_in_size; /* the size of the receive buffer */
+ __u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
+ __u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
+ struct kref kref;
+};
+#define to_skel_dev(d) container_of(d, struct usb_skel, kref)
+
+static struct usb_driver skel_driver;
+
+static void skel_delete(struct kref *kref)
+{
+ struct usb_skel *dev = to_skel_dev(kref);
+
+ usb_put_dev(dev->udev);
+ kfree (dev->bulk_in_buffer);
+ kfree (dev);
+}
+
+static int skel_open(struct inode *inode, struct file *file)
+{
+ struct usb_skel *dev;
+ struct usb_interface *interface;
+ int subminor;
+ int retval = 0;
+
+ subminor = iminor(inode);
+
+ interface = usb_find_interface(&skel_driver, subminor);
+ if (!interface) {
+ err ("%s - error, can't find device for minor %d",
+ __FUNCTION__, subminor);
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ dev = usb_get_intfdata(interface);
+ if (!dev) {
+ retval = -ENODEV;
+ goto exit;
+ }
+
+ /* increment our usage count for the device */
+ kref_get(&dev->kref);
+
+ /* save our object in the file's private structure */
+ file->private_data = dev;
+
+exit:
+ return retval;
+}
+
+static int skel_release(struct inode *inode, struct file *file)
+{
+ struct usb_skel *dev;
+
+ dev = (struct usb_skel *)file->private_data;
+ if (dev == NULL)
+ return -ENODEV;
+
+ /* decrement the count on our device */
+ kref_put(&dev->kref, skel_delete);
+ return 0;
+}
+
+static ssize_t skel_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+ struct usb_skel *dev;
+ int retval = 0;
+ int bytes_read;
+
+ dev = (struct usb_skel *)file->private_data;
+
+ /* do a blocking bulk read to get data from the device */
+ retval = usb_bulk_msg(dev->udev,
+ usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
+ dev->bulk_in_buffer,
+ min(dev->bulk_in_size, count),
+ &bytes_read, 10000);
+
+ /* if the read was successful, copy the data to userspace */
+ if (!retval) {
+ if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
+ retval = -EFAULT;
+ else
+ retval = bytes_read;
+ }
+
+ return retval;
+}
+
+static void skel_write_bulk_callback(struct urb *urb, struct pt_regs *regs)
+{
+ struct usb_skel *dev;
+
+ dev = (struct usb_skel *)urb->context;
+
+ /* sync/async unlink faults aren't errors */
+ if (urb->status &&
+ !(urb->status == -ENOENT ||
+ urb->status == -ECONNRESET ||
+ urb->status == -ESHUTDOWN)) {
+ dbg("%s - nonzero write bulk status received: %d",
+ __FUNCTION__, urb->status);
+ }
+
+ /* free up our allocated buffer */
+ usb_buffer_free(urb->dev, urb->transfer_buffer_length,
+ urb->transfer_buffer, urb->transfer_dma);
+}
+
+static ssize_t skel_write(struct file *file, const char *user_buffer, size_t count, loff_t *ppos)
+{
+ struct usb_skel *dev;
+ int retval = 0;
+ struct urb *urb = NULL;
+ char *buf = NULL;
+
+ dev = (struct usb_skel *)file->private_data;
+
+ /* verify that we actually have some data to write */
+ if (count == 0)
+ goto exit;
+
+ /* create a urb, and a buffer for it, and copy the data to the urb */
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ buf = usb_buffer_alloc(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
+ if (!buf) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ if (copy_from_user(buf, user_buffer, count)) {
+ retval = -EFAULT;
+ goto error;
+ }
+
+ /* initialize the urb properly */
+ usb_fill_bulk_urb(urb, dev->udev,
+ usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
+ buf, count, skel_write_bulk_callback, dev);
+ urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+ /* send the data out the bulk port */
+ retval = usb_submit_urb(urb, GFP_KERNEL);
+ if (retval) {
+ err("%s - failed submitting write urb, error %d", __FUNCTION__, retval);
+ goto error;
+ }
+
+ /* release our reference to this urb, the USB core will eventually free it entirely */
+ usb_free_urb(urb);
+
+exit:
+ return count;
+
+error:
+ usb_buffer_free(dev->udev, count, buf, urb->transfer_dma);
+ usb_free_urb(urb);
+ return retval;
+}
+
+static struct file_operations skel_fops = {
+ .owner = THIS_MODULE,
+ .read = skel_read,
+ .write = skel_write,
+ .open = skel_open,
+ .release = skel_release,
+};
+
+/*
+ * usb class driver info in order to get a minor number from the usb core,
+ * and to have the device registered with devfs and the driver core
+ */
+static struct usb_class_driver skel_class = {
+ .name = "usb/skel%d",
+ .fops = &skel_fops,
+ .mode = S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH,
+ .minor_base = USB_SKEL_MINOR_BASE,
+};
+
+static int skel_probe(struct usb_interface *interface, const struct usb_device_id *id)
+{
+ struct usb_skel *dev = NULL;
+ struct usb_host_interface *iface_desc;
+ struct usb_endpoint_descriptor *endpoint;
+ size_t buffer_size;
+ int i;
+ int retval = -ENOMEM;
+
+ /* allocate memory for our device state and initialize it */
+ dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+ if (dev == NULL) {
+ err("Out of memory");
+ goto error;
+ }
+ memset(dev, 0x00, sizeof(*dev));
+ kref_init(&dev->kref);
+
+ dev->udev = usb_get_dev(interface_to_usbdev(interface));
+ dev->interface = interface;
+
+ /* set up the endpoint information */
+ /* use only the first bulk-in and bulk-out endpoints */
+ iface_desc = interface->cur_altsetting;
+ for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
+ endpoint = &iface_desc->endpoint[i].desc;
+
+ if (!dev->bulk_in_endpointAddr &&
+ (endpoint->bEndpointAddress & USB_DIR_IN) &&
+ ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+ == USB_ENDPOINT_XFER_BULK)) {
+ /* we found a bulk in endpoint */
+ buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
+ 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");
+ goto error;
+ }
+ }
+
+ if (!dev->bulk_out_endpointAddr &&
+ !(endpoint->bEndpointAddress & USB_DIR_OUT) &&
+ ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
+ == USB_ENDPOINT_XFER_BULK)) {
+ /* we found a bulk out endpoint */
+ dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
+ }
+ }
+ if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
+ err("Could not find both bulk-in and bulk-out endpoints");
+ goto error;
+ }
+
+ /* save our data pointer in this interface device */
+ usb_set_intfdata(interface, dev);
+
+ /* we can register the device now, as it is ready */
+ 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.");
+ usb_set_intfdata(interface, NULL);
+ goto error;
+ }
+
+ /* let the user know what node this device is now attached to */
+ info("USB Skeleton device now attached to USBSkel-%d", interface->minor);
+ return 0;
+
+error:
+ if (dev)
+ kref_put(&dev->kref, skel_delete);
+ return retval;
+}
+
+static void skel_disconnect(struct usb_interface *interface)
+{
+ struct usb_skel *dev;
+ int minor = interface->minor;
+
+ /* prevent skel_open() from racing skel_disconnect() */
+ lock_kernel();
+
+ dev = usb_get_intfdata(interface);
+ usb_set_intfdata(interface, NULL);
+
+ /* give back our minor */
+ usb_deregister_dev(interface, &skel_class);
+
+ unlock_kernel();
+
+ /* decrement our usage count */
+ kref_put(&dev->kref, skel_delete);
+
+ info("USB Skeleton #%d now disconnected", minor);
+}
+
+static struct usb_driver skel_driver = {
+ .owner = THIS_MODULE,
+ .name = "skeleton",
+ .probe = skel_probe,
+ .disconnect = skel_disconnect,
+ .id_table = skel_table,
+};
+
+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_LICENSE("GPL");