diff options
Diffstat (limited to 'drivers/usb/class/cdc-wdm.c')
| -rw-r--r-- | drivers/usb/class/cdc-wdm.c | 740 |
1 files changed, 740 insertions, 0 deletions
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c new file mode 100644 index 00000000000..731db051070 --- /dev/null +++ b/drivers/usb/class/cdc-wdm.c @@ -0,0 +1,740 @@ +/* + * cdc-wdm.c + * + * This driver supports USB CDC WCM Device Management. + * + * Copyright (c) 2007-2008 Oliver Neukum + * + * Some code taken from cdc-acm.c + * + * Released under the GPLv2. + * + * Many thanks to Carl Nordbeck + */ +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/smp_lock.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> +#include <linux/bitops.h> +#include <linux/poll.h> +#include <linux/usb.h> +#include <linux/usb/cdc.h> +#include <asm/byteorder.h> +#include <asm/unaligned.h> + +/* + * Version Information + */ +#define DRIVER_VERSION "v0.02" +#define DRIVER_AUTHOR "Oliver Neukum" + +static struct usb_device_id wdm_ids[] = { + { + .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS | + USB_DEVICE_ID_MATCH_INT_SUBCLASS, + .bInterfaceClass = USB_CLASS_COMM, + .bInterfaceSubClass = USB_CDC_SUBCLASS_DMM + }, + { } +}; + +#define WDM_MINOR_BASE 176 + + +#define WDM_IN_USE 1 +#define WDM_DISCONNECTING 2 +#define WDM_RESULT 3 +#define WDM_READ 4 +#define WDM_INT_STALL 5 +#define WDM_POLL_RUNNING 6 + + +#define WDM_MAX 16 + + +static DEFINE_MUTEX(wdm_mutex); + +/* --- method tables --- */ + +struct wdm_device { + u8 *inbuf; /* buffer for response */ + u8 *outbuf; /* buffer for command */ + u8 *sbuf; /* buffer for status */ + u8 *ubuf; /* buffer for copy to user space */ + + struct urb *command; + struct urb *response; + struct urb *validity; + struct usb_interface *intf; + struct usb_ctrlrequest *orq; + struct usb_ctrlrequest *irq; + spinlock_t iuspin; + + unsigned long flags; + u16 bufsize; + u16 wMaxCommand; + u16 wMaxPacketSize; + u16 bMaxPacketSize0; + __le16 inum; + int reslength; + int length; + int read; + int count; + dma_addr_t shandle; + dma_addr_t ihandle; + struct mutex wlock; + struct mutex rlock; + wait_queue_head_t wait; + struct work_struct rxwork; + int werr; + int rerr; +}; + +static struct usb_driver wdm_driver; + +/* --- callbacks --- */ +static void wdm_out_callback(struct urb *urb) +{ + struct wdm_device *desc; + desc = urb->context; + spin_lock(&desc->iuspin); + desc->werr = urb->status; + spin_unlock(&desc->iuspin); + clear_bit(WDM_IN_USE, &desc->flags); + kfree(desc->outbuf); + wake_up(&desc->wait); +} + +static void wdm_in_callback(struct urb *urb) +{ + struct wdm_device *desc = urb->context; + int status = urb->status; + + spin_lock(&desc->iuspin); + + if (status) { + switch (status) { + case -ENOENT: + dev_dbg(&desc->intf->dev, + "nonzero urb status received: -ENOENT"); + break; + case -ECONNRESET: + dev_dbg(&desc->intf->dev, + "nonzero urb status received: -ECONNRESET"); + break; + case -ESHUTDOWN: + dev_dbg(&desc->intf->dev, + "nonzero urb status received: -ESHUTDOWN"); + break; + case -EPIPE: + err("nonzero urb status received: -EPIPE"); + break; + default: + err("Unexpected error %d", status); + break; + } + } + + desc->rerr = status; + desc->reslength = urb->actual_length; + memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength); + desc->length += desc->reslength; + wake_up(&desc->wait); + + set_bit(WDM_READ, &desc->flags); + spin_unlock(&desc->iuspin); +} + +static void wdm_int_callback(struct urb *urb) +{ + int rv = 0; + int status = urb->status; + struct wdm_device *desc; + struct usb_ctrlrequest *req; + struct usb_cdc_notification *dr; + + desc = urb->context; + req = desc->irq; + dr = (struct usb_cdc_notification *)desc->sbuf; + + if (status) { + switch (status) { + case -ESHUTDOWN: + case -ENOENT: + case -ECONNRESET: + return; /* unplug */ + case -EPIPE: + set_bit(WDM_INT_STALL, &desc->flags); + err("Stall on int endpoint"); + goto sw; /* halt is cleared in work */ + default: + err("nonzero urb status received: %d", status); + break; + } + } + + if (urb->actual_length < sizeof(struct usb_cdc_notification)) { + err("wdm_int_callback - %d bytes", urb->actual_length); + goto exit; + } + + switch (dr->bNotificationType) { + case USB_CDC_NOTIFY_RESPONSE_AVAILABLE: + dev_dbg(&desc->intf->dev, + "NOTIFY_RESPONSE_AVAILABLE received: index %d len %d", + dr->wIndex, dr->wLength); + break; + + case USB_CDC_NOTIFY_NETWORK_CONNECTION: + + dev_dbg(&desc->intf->dev, + "NOTIFY_NETWORK_CONNECTION %s network", + dr->wValue ? "connected to" : "disconnected from"); + goto exit; + default: + clear_bit(WDM_POLL_RUNNING, &desc->flags); + err("unknown notification %d received: index %d len %d", + dr->bNotificationType, dr->wIndex, dr->wLength); + goto exit; + } + + req->bRequestType = (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE); + req->bRequest = USB_CDC_GET_ENCAPSULATED_RESPONSE; + req->wValue = 0; + req->wIndex = desc->inum; + req->wLength = cpu_to_le16(desc->bMaxPacketSize0); + + usb_fill_control_urb( + desc->response, + interface_to_usbdev(desc->intf), + /* using common endpoint 0 */ + usb_rcvctrlpipe(interface_to_usbdev(desc->intf), 0), + (unsigned char *)req, + desc->inbuf, + desc->bMaxPacketSize0, + wdm_in_callback, + desc + ); + desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + spin_lock(&desc->iuspin); + clear_bit(WDM_READ, &desc->flags); + if (!test_bit(WDM_DISCONNECTING, &desc->flags)) { + rv = usb_submit_urb(desc->response, GFP_ATOMIC); + dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d", + __func__, rv); + } + spin_unlock(&desc->iuspin); + if (rv < 0) { + if (rv == -EPERM) + return; + if (rv == -ENOMEM) { +sw: + rv = schedule_work(&desc->rxwork); + if (rv) + err("Cannot schedule work"); + } + } +exit: + rv = usb_submit_urb(urb, GFP_ATOMIC); + if (rv) + err("%s - usb_submit_urb failed with result %d", + __func__, rv); + +} + +static void kill_urbs(struct wdm_device *desc) +{ + usb_kill_urb(desc->command); + usb_kill_urb(desc->validity); + usb_kill_urb(desc->response); +} + +static void free_urbs(struct wdm_device *desc) +{ + usb_free_urb(desc->validity); + usb_free_urb(desc->response); + usb_free_urb(desc->command); +} + +static void cleanup(struct wdm_device *desc) +{ + usb_buffer_free(interface_to_usbdev(desc->intf), + desc->wMaxPacketSize, + desc->sbuf, + desc->validity->transfer_dma); + usb_buffer_free(interface_to_usbdev(desc->intf), + desc->wMaxPacketSize, + desc->inbuf, + desc->response->transfer_dma); + kfree(desc->orq); + kfree(desc->irq); + kfree(desc->ubuf); + free_urbs(desc); + kfree(desc); +} + +static ssize_t wdm_write +(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) +{ + u8 *buf; + int rv = -EMSGSIZE, r, we; + struct wdm_device *desc = file->private_data; + struct usb_ctrlrequest *req; + + if (count > desc->wMaxCommand) + count = desc->wMaxCommand; + + spin_lock_irq(&desc->iuspin); + we = desc->werr; + desc->werr = 0; + spin_unlock_irq(&desc->iuspin); + if (we < 0) + return -EIO; + + r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */ + rv = -ERESTARTSYS; + if (r) + goto outnl; + + r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE, + &desc->flags)); + if (r < 0) + goto out; + + if (test_bit(WDM_DISCONNECTING, &desc->flags)) { + rv = -ENODEV; + goto out; + } + + desc->outbuf = buf = kmalloc(count, GFP_KERNEL); + if (!buf) { + rv = -ENOMEM; + goto out; + } + + r = copy_from_user(buf, buffer, count); + if (r > 0) { + kfree(buf); + rv = -EFAULT; + goto out; + } + + req = desc->orq; + usb_fill_control_urb( + desc->command, + interface_to_usbdev(desc->intf), + /* using common endpoint 0 */ + usb_sndctrlpipe(interface_to_usbdev(desc->intf), 0), + (unsigned char *)req, + buf, + count, + wdm_out_callback, + desc + ); + + req->bRequestType = (USB_DIR_OUT | USB_TYPE_CLASS | + USB_RECIP_INTERFACE); + req->bRequest = USB_CDC_SEND_ENCAPSULATED_COMMAND; + req->wValue = 0; + req->wIndex = desc->inum; + req->wLength = cpu_to_le16(count); + set_bit(WDM_IN_USE, &desc->flags); + + rv = usb_submit_urb(desc->command, GFP_KERNEL); + if (rv < 0) { + kfree(buf); + clear_bit(WDM_IN_USE, &desc->flags); + } else { + dev_dbg(&desc->intf->dev, "Tx URB has been submitted index=%d", + req->wIndex); + } +out: + mutex_unlock(&desc->wlock); +outnl: + return rv < 0 ? rv : count; +} + +static ssize_t wdm_read +(struct file *file, char __user *buffer, size_t count, loff_t *ppos) +{ + int rv, cntr; + int i = 0; + struct wdm_device *desc = file->private_data; + + + rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */ + if (rv < 0) + return -ERESTARTSYS; + + if (desc->length == 0) { + desc->read = 0; +retry: + i++; + rv = wait_event_interruptible(desc->wait, + test_bit(WDM_READ, &desc->flags)); + + if (rv < 0) { + rv = -ERESTARTSYS; + goto err; + } + + spin_lock_irq(&desc->iuspin); + + if (desc->rerr) { /* read completed, error happened */ + int t = desc->rerr; + desc->rerr = 0; + spin_unlock_irq(&desc->iuspin); + err("reading had resulted in %d", t); + rv = -EIO; + goto err; + } + /* + * recheck whether we've lost the race + * against the completion handler + */ + if (!test_bit(WDM_READ, &desc->flags)) { /* lost race */ + spin_unlock_irq(&desc->iuspin); + goto retry; + } + if (!desc->reslength) { /* zero length read */ + spin_unlock_irq(&desc->iuspin); + goto retry; + } + clear_bit(WDM_READ, &desc->flags); + spin_unlock_irq(&desc->iuspin); + } + + cntr = count > desc->length ? desc->length : count; + rv = copy_to_user(buffer, desc->ubuf, cntr); + if (rv > 0) { + rv = -EFAULT; + goto err; + } + + for (i = 0; i < desc->length - cntr; i++) + desc->ubuf[i] = desc->ubuf[i + cntr]; + + desc->length -= cntr; + rv = cntr; + +err: + mutex_unlock(&desc->rlock); + if (rv < 0) + err("wdm_read: exit error"); + return rv; +} + +static int wdm_flush(struct file *file, fl_owner_t id) +{ + struct wdm_device *desc = file->private_data; + + wait_event(desc->wait, !test_bit(WDM_IN_USE, &desc->flags)); + if (desc->werr < 0) + err("Error in flush path: %d", desc->werr); + + return desc->werr; +} + +static unsigned int wdm_poll(struct file *file, struct poll_table_struct *wait) +{ + struct wdm_device *desc = file->private_data; + unsigned long flags; + unsigned int mask = 0; + + spin_lock_irqsave(&desc->iuspin, flags); + if (test_bit(WDM_DISCONNECTING, &desc->flags)) { + mask = POLLERR; + spin_unlock_irqrestore(&desc->iuspin, flags); + goto desc_out; + } + if (test_bit(WDM_READ, &desc->flags)) + mask = POLLIN | POLLRDNORM; + if (desc->rerr || desc->werr) + mask |= POLLERR; + if (!test_bit(WDM_IN_USE, &desc->flags)) + mask |= POLLOUT | POLLWRNORM; + spin_unlock_irqrestore(&desc->iuspin, flags); + + poll_wait(file, &desc->wait, wait); + +desc_out: + return mask; +} + +static int wdm_open(struct inode *inode, struct file *file) +{ + int minor = iminor(inode); + int rv = -ENODEV; + struct usb_interface *intf; + struct wdm_device *desc; + + mutex_lock(&wdm_mutex); + intf = usb_find_interface(&wdm_driver, minor); + if (!intf) + goto out; + + desc = usb_get_intfdata(intf); + if (test_bit(WDM_DISCONNECTING, &desc->flags)) + goto out; + + desc->count++; + file->private_data = desc; + + rv = usb_submit_urb(desc->validity, GFP_KERNEL); + + if (rv < 0) { + desc->count--; + err("Error submitting int urb - %d", rv); + goto out; + } + rv = 0; + +out: + mutex_unlock(&wdm_mutex); + return rv; +} + +static int wdm_release(struct inode *inode, struct file *file) +{ + struct wdm_device *desc = file->private_data; + + mutex_lock(&wdm_mutex); + desc->count--; + if (!desc->count) { + dev_dbg(&desc->intf->dev, "wdm_release: cleanup"); + kill_urbs(desc); + } + mutex_unlock(&wdm_mutex); + return 0; +} + +static const struct file_operations wdm_fops = { + .owner = THIS_MODULE, + .read = wdm_read, + .write = wdm_write, + .open = wdm_open, + .flush = wdm_flush, + .release = wdm_release, + .poll = wdm_poll +}; + +static struct usb_class_driver wdm_class = { + .name = "cdc-wdm%d", + .fops = &wdm_fops, + .minor_base = WDM_MINOR_BASE, +}; + +/* --- error handling --- */ +static void wdm_rxwork(struct work_struct *work) +{ + struct wdm_device *desc = container_of(work, struct wdm_device, rxwork); + unsigned long flags; + int rv; + + spin_lock_irqsave(&desc->iuspin, flags); + if (test_bit(WDM_DISCONNECTING, &desc->flags)) { + spin_unlock_irqrestore(&desc->iuspin, flags); + } else { + spin_unlock_irqrestore(&desc->iuspin, flags); + rv = usb_submit_urb(desc->response, GFP_KERNEL); + if (rv < 0 && rv != -EPERM) { + spin_lock_irqsave(&desc->iuspin, flags); + if (!test_bit(WDM_DISCONNECTING, &desc->flags)) + schedule_work(&desc->rxwork); + spin_unlock_irqrestore(&desc->iuspin, flags); + } + } +} + +/* --- hotplug --- */ + +static int wdm_probe(struct usb_interface *intf, const struct usb_device_id *id) +{ + int rv = -EINVAL; + struct usb_device *udev = interface_to_usbdev(intf); + struct wdm_device *desc; + struct usb_host_interface *iface; + struct usb_endpoint_descriptor *ep; + struct usb_cdc_dmm_desc *dmhd; + u8 *buffer = intf->altsetting->extra; + int buflen = intf->altsetting->extralen; + u16 maxcom = 0; + + if (!buffer) + goto out; + + while (buflen > 0) { + if (buffer [1] != USB_DT_CS_INTERFACE) { + err("skipping garbage"); + goto next_desc; + } + + switch (buffer [2]) { + case USB_CDC_HEADER_TYPE: + break; + case USB_CDC_DMM_TYPE: + dmhd = (struct usb_cdc_dmm_desc *)buffer; + maxcom = le16_to_cpu(dmhd->wMaxCommand); + dev_dbg(&intf->dev, + "Finding maximum buffer length: %d", maxcom); + break; + default: + err("Ignoring extra header, type %d, length %d", + buffer[2], buffer[0]); + break; + } +next_desc: + buflen -= buffer[0]; + buffer += buffer[0]; + } + + rv = -ENOMEM; + desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL); + if (!desc) + goto out; + mutex_init(&desc->wlock); + mutex_init(&desc->rlock); + spin_lock_init(&desc->iuspin); + init_waitqueue_head(&desc->wait); + desc->wMaxCommand = maxcom; + desc->inum = cpu_to_le16((u16)intf->cur_altsetting->desc.bInterfaceNumber); + desc->intf = intf; + INIT_WORK(&desc->rxwork, wdm_rxwork); + + iface = &intf->altsetting[0]; + ep = &iface->endpoint[0].desc; + if (!usb_endpoint_is_int_in(ep)) { + rv = -EINVAL; + goto err; + } + + desc->wMaxPacketSize = le16_to_cpu(ep->wMaxPacketSize); + desc->bMaxPacketSize0 = udev->descriptor.bMaxPacketSize0; + + desc->orq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL); + if (!desc->orq) + goto err; + desc->irq = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL); + if (!desc->irq) + goto err; + + desc->validity = usb_alloc_urb(0, GFP_KERNEL); + if (!desc->validity) + goto err; + + desc->response = usb_alloc_urb(0, GFP_KERNEL); + if (!desc->response) + goto err; + + desc->command = usb_alloc_urb(0, GFP_KERNEL); + if (!desc->command) + goto err; + + desc->ubuf = kmalloc(desc->wMaxCommand, GFP_KERNEL); + if (!desc->ubuf) + goto err; + + desc->sbuf = usb_buffer_alloc(interface_to_usbdev(intf), + desc->wMaxPacketSize, + GFP_KERNEL, + &desc->validity->transfer_dma); + if (!desc->sbuf) + goto err; + + desc->inbuf = usb_buffer_alloc(interface_to_usbdev(intf), + desc->bMaxPacketSize0, + GFP_KERNEL, + &desc->response->transfer_dma); + if (!desc->inbuf) + goto err2; + + usb_fill_int_urb( + desc->validity, + interface_to_usbdev(intf), + usb_rcvintpipe(interface_to_usbdev(intf), ep->bEndpointAddress), + desc->sbuf, + desc->wMaxPacketSize, + wdm_int_callback, + desc, + ep->bInterval + ); + desc->validity->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + + usb_set_intfdata(intf, desc); + rv = usb_register_dev(intf, &wdm_class); + dev_info(&intf->dev, "cdc-wdm%d: USB WDM device\n", + intf->minor - WDM_MINOR_BASE); + if (rv < 0) + goto err; +out: + return rv; +err2: + usb_buffer_free(interface_to_usbdev(desc->intf), + desc->wMaxPacketSize, + desc->sbuf, + desc->validity->transfer_dma); +err: + free_urbs(desc); + kfree(desc->ubuf); + kfree(desc->orq); + kfree(desc->irq); + kfree(desc); + return rv; +} + +static void wdm_disconnect(struct usb_interface *intf) +{ + struct wdm_device *desc; + unsigned long flags; + + usb_deregister_dev(intf, &wdm_class); + mutex_lock(&wdm_mutex); + desc = usb_get_intfdata(intf); + + /* the spinlock makes sure no new urbs are generated in the callbacks */ + spin_lock_irqsave(&desc->iuspin, flags); + set_bit(WDM_DISCONNECTING, &desc->flags); + set_bit(WDM_READ, &desc->flags); + clear_bit(WDM_IN_USE, &desc->flags); + spin_unlock_irqrestore(&desc->iuspin, flags); + cancel_work_sync(&desc->rxwork); + kill_urbs(desc); + wake_up_all(&desc->wait); + if (!desc->count) + cleanup(desc); + mutex_unlock(&wdm_mutex); +} + +static struct usb_driver wdm_driver = { + .name = "cdc_wdm", + .probe = wdm_probe, + .disconnect = wdm_disconnect, + .id_table = wdm_ids, +}; + +/* --- low level module stuff --- */ + +static int __init wdm_init(void) +{ + int rv; + + rv = usb_register(&wdm_driver); + + return rv; +} + +static void __exit wdm_exit(void) +{ + usb_deregister(&wdm_driver); +} + +module_init(wdm_init); +module_exit(wdm_exit); + +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION("USB Abstract Control Model driver for " + "USB WCM Device Management"); +MODULE_LICENSE("GPL"); |