diff options
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 | 
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 | 
| commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
| tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/usb-skeleton.c | |
Linux-2.6.12-rc2v2.6.12-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.c | 360 | 
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 000000000000..6051a646fe69 --- /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"); | 
