diff options
Diffstat (limited to 'recipes-kernel/mocca-usb/_files/mocca_usb.c')
| -rw-r--r-- | recipes-kernel/mocca-usb/_files/mocca_usb.c | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/recipes-kernel/mocca-usb/_files/mocca_usb.c b/recipes-kernel/mocca-usb/_files/mocca_usb.c new file mode 100644 index 000000000..1a6793c80 --- /dev/null +++ b/recipes-kernel/mocca-usb/_files/mocca_usb.c @@ -0,0 +1,391 @@ +/* + * USB Skeleton driver - 2.2 + * + * 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 easier to read and use. + * + */ + +#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 <linux/uaccess.h> +#include <linux/usb.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> + + +/* Define these values to match your devices */ +#define USB_MOCCA_VENDOR_ID 0x184f +#define USB_MOCCA_PRODUCT_ID_1 0x0007 +#define USB_MOCCA_PRODUCT_ID_2 0x0008 +#define USB_MOCCA_PRODUCT_ID_3 0x0009 +#define USB_MOCCA_PRODUCT_ID_4 0x0010 +#define USB_MOCCA_PRODUCT_ID_5 0x0011 +#define USB_MOCCA_PRODUCT_ID_6 0x0012 + +/* table of devices that work with this driver */ +static const struct usb_device_id mocca_table[] = { + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_1) }, + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_2) }, + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_3) }, + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_4) }, + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_5) }, + { USB_DEVICE(USB_MOCCA_VENDOR_ID, USB_MOCCA_PRODUCT_ID_6) }, + { } /* Terminating entry */ +}; +MODULE_DEVICE_TABLE (usb, mocca_table); + + +/* Get a minor range for your devices from the usb maintainer */ +#define USB_MOCCA_MINOR_BASE 221 /*TODO: change this minor number */ + +/* our private defines. if this grows any larger, use your own .h file */ +#define MAX_TRANSFER ( PAGE_SIZE - 512 ) +#define WRITES_IN_FLIGHT 8 + +/* Structure to hold all of our device specific stuff */ +struct mocca_skel { + struct usb_device * udev; /* the usb device for this device */ + struct usb_interface * interface; /* the interface for this device */ + struct semaphore limit_sem; /* limiting the number of writes in progress */ + 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_mocca_dev(d) container_of(d, struct mocca_skel, kref) + +static struct usb_driver mocca_driver; +static spinlock_t spinLock; + +static void mocca_delete(struct kref *kref) +{ + struct mocca_skel *dev = to_mocca_dev(kref); + + usb_put_dev(dev->udev); + kfree (dev->bulk_in_buffer); + kfree (dev); +} + +static int mocca_open(struct inode *inode, struct file *file) +{ + struct mocca_skel *dev; + struct usb_interface *interface; + int subminor; + int retval = 0; + + subminor = iminor(inode); + + interface = usb_find_interface(&mocca_driver, subminor); + if (!interface) { + printk(KERN_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 mocca_release(struct inode *inode, struct file *file) +{ + struct mocca_skel *dev; + + dev = (struct mocca_skel *)file->private_data; + if (dev == NULL) + return -ENODEV; + + /* decrement the count on our device */ + kref_put(&dev->kref, mocca_delete); + return 0; +} + +static ssize_t mocca_read(struct file *file, char *buffer, size_t count, loff_t *ppos) +{ + struct mocca_skel *dev; + int retval = 0; + int bytes_read; + + dev = (struct mocca_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 mocca_write_bulk_callback(struct urb *urb) +{ + struct mocca_skel *dev; + + dev = (struct mocca_skel *)urb->context; + + /* sync/async unlink faults aren't errors */ + if (urb->status && + !(urb->status == -ENOENT || + urb->status == -ECONNRESET || + urb->status == -ESHUTDOWN)) { + printk(KERN_ERR "%s - nonzero write bulk status received: %d", + __FUNCTION__, urb->status); + } + + /* free up our allocated buffer */ + usb_free_coherent(urb->dev, urb->transfer_buffer_length, + urb->transfer_buffer, urb->transfer_dma); + up(&dev->limit_sem); +} + +static ssize_t mocca_write(struct file *file, const char *user_buffer, size_t count, loff_t *ppos) +{ + struct mocca_skel *dev; + int retval = 0; + struct urb *urb = NULL; + char *buf = NULL; + size_t writesize = min(count, (size_t)MAX_TRANSFER); + + dev = (struct mocca_skel *)file->private_data; + + /* verify that we actually have some data to write */ + if (count == 0) + goto exit; + + /* limit the number of URBs in flight to stop a user from using up all RAM */ + if (down_interruptible(&dev->limit_sem)) { + retval = -ERESTARTSYS; + 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_alloc_coherent(dev->udev, writesize, GFP_KERNEL, &urb->transfer_dma); + if (!buf) { + retval = -ENOMEM; + goto error; + } + + if (copy_from_user(buf, user_buffer, writesize)) { + retval = -EFAULT; + goto error; + } + + /* initialize the urb properly */ + usb_fill_bulk_urb(urb, dev->udev, + usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr), + buf, writesize, mocca_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) { + printk(KERN_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 writesize; + +error: + usb_free_coherent(dev->udev, writesize, buf, urb->transfer_dma); + usb_free_urb(urb); + up(&dev->limit_sem); + return retval; +} + +static struct file_operations mocca_fops = { + .owner = THIS_MODULE, + .read = mocca_read, + .write = mocca_write, + .open = mocca_open, + .release = mocca_release, +}; + +/* + * usb class driver info in order to get a minor number from the usb core, + * and to have the device registered with the driver core + */ +static struct usb_class_driver mocca_class = { + .name = "mocca%d", + .fops = &mocca_fops, + .minor_base = USB_MOCCA_MINOR_BASE, +}; + +static int mocca_probe(struct usb_interface *interface, const struct usb_device_id *id) +{ + struct mocca_skel *dev = NULL; + struct usb_host_interface *iface_desc; + struct usb_endpoint_descriptor *endpoint; + size_t buffer_size; + int i; + int retval = -ENOMEM; + + spin_lock_init(&spinLock); + + /* allocate memory for our device state and initialize it */ + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (dev == NULL) { + printk(KERN_ERR "Out of memory"); + goto error; + } + kref_init(&dev->kref); + sema_init(&dev->limit_sem, WRITES_IN_FLIGHT); + + 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_ENDPOINT_DIR_MASK) + == 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) { + printk(KERN_ERR "Could not allocate bulk_in_buffer"); + goto error; + } + printk(KERN_INFO "Found bulk-in pipe, adress: %x, max packet size: %d", endpoint->bEndpointAddress, endpoint->wMaxPacketSize); + } + + if (!dev->bulk_out_endpointAddr && + ((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK) + == 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; + printk(KERN_INFO "Found bulk-out pipe, adress: %x, max packet size: %d", endpoint->bEndpointAddress, endpoint->wMaxPacketSize); + } + } + if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) { + printk(KERN_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, &mocca_class); + if (retval) { + /* something prevented us from registering this driver */ + printk(KERN_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 */ + dev_info(&interface->dev, + "K2L MOCCA device now attached to mocca%d", + interface->minor); + return 0; + +error: + if (dev) + kref_put(&dev->kref, mocca_delete); + return retval; +} + +static void mocca_disconnect(struct usb_interface *interface) +{ + struct mocca_skel *dev; + int minor = interface->minor; + + /* prevent mocca_open() from racing mocca_disconnect() */ + spin_lock(&spinLock); + + dev = usb_get_intfdata(interface); + usb_set_intfdata(interface, NULL); + + /* give back our minor */ + usb_deregister_dev(interface, &mocca_class); + + spin_unlock(&spinLock); + + /* decrement our usage count */ + kref_put(&dev->kref, mocca_delete); + + dev_info(&interface->dev, "K2L MOCCA device #%d now disconnected", minor); +} + +static struct usb_driver mocca_driver = { + .name = "k2l-mocca", + .probe = mocca_probe, + .disconnect = mocca_disconnect, + .id_table = mocca_table, +}; + +static int __init usb_mocca_init(void) +{ + int result; + + /* register this driver with the USB subsystem */ + result = usb_register(&mocca_driver); + if (result) + printk(KERN_ERR "usb_register failed. Error number %d", result); + + return result; +} + +static void __exit usb_mocca_exit(void) +{ + /* deregister this driver with the USB subsystem */ + usb_deregister(&mocca_driver); +} + +module_init (usb_mocca_init); +module_exit (usb_mocca_exit); + +MODULE_LICENSE("GPL"); |