diff options
Diffstat (limited to 'kernel/drivers/usb/misc/usblcd.c')
| -rw-r--r-- | kernel/drivers/usb/misc/usblcd.c | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/kernel/drivers/usb/misc/usblcd.c b/kernel/drivers/usb/misc/usblcd.c new file mode 100644 index 000000000..118439050 --- /dev/null +++ b/kernel/drivers/usb/misc/usblcd.c @@ -0,0 +1,460 @@ +/***************************************************************************** + * USBLCD Kernel Driver * + * Version 1.05 * + * (C) 2005 Georges Toth <g.toth@e-biz.lu> * + * * + * This file is licensed under the GPL. See COPYING in the package. * + * Based on usb-skeleton.c 2.0 by Greg Kroah-Hartman (greg@kroah.com) * + * * + * * + * 28.02.05 Complete rewrite of the original usblcd.c driver, * + * based on usb_skeleton.c. * + * This new driver allows more than one USB-LCD to be connected * + * and controlled, at once * + *****************************************************************************/ +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> +#include <linux/usb.h> + +#define DRIVER_VERSION "USBLCD Driver Version 1.05" + +#define USBLCD_MINOR 144 + +#define IOCTL_GET_HARD_VERSION 1 +#define IOCTL_GET_DRV_VERSION 2 + + +static DEFINE_MUTEX(lcd_mutex); +static const struct usb_device_id id_table[] = { + { .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, }, + { }, +}; +MODULE_DEVICE_TABLE(usb, id_table); + +static DEFINE_MUTEX(open_disc_mutex); + + +struct usb_lcd { + struct usb_device *udev; /* init: probe_lcd */ + 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; + struct semaphore limit_sem; /* to stop writes at + full throttle from + using up all RAM */ + struct usb_anchor submitted; /* URBs to wait for + before suspend */ +}; +#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref) + +#define USB_LCD_CONCURRENT_WRITES 5 + +static struct usb_driver lcd_driver; + + +static void lcd_delete(struct kref *kref) +{ + struct usb_lcd *dev = to_lcd_dev(kref); + + usb_put_dev(dev->udev); + kfree(dev->bulk_in_buffer); + kfree(dev); +} + + +static int lcd_open(struct inode *inode, struct file *file) +{ + struct usb_lcd *dev; + struct usb_interface *interface; + int subminor, r; + + mutex_lock(&lcd_mutex); + subminor = iminor(inode); + + interface = usb_find_interface(&lcd_driver, subminor); + if (!interface) { + mutex_unlock(&lcd_mutex); + printk(KERN_ERR "USBLCD: %s - error, can't find device for minor %d\n", + __func__, subminor); + return -ENODEV; + } + + mutex_lock(&open_disc_mutex); + dev = usb_get_intfdata(interface); + if (!dev) { + mutex_unlock(&open_disc_mutex); + mutex_unlock(&lcd_mutex); + return -ENODEV; + } + + /* increment our usage count for the device */ + kref_get(&dev->kref); + mutex_unlock(&open_disc_mutex); + + /* grab a power reference */ + r = usb_autopm_get_interface(interface); + if (r < 0) { + kref_put(&dev->kref, lcd_delete); + mutex_unlock(&lcd_mutex); + return r; + } + + /* save our object in the file's private structure */ + file->private_data = dev; + mutex_unlock(&lcd_mutex); + + return 0; +} + +static int lcd_release(struct inode *inode, struct file *file) +{ + struct usb_lcd *dev; + + dev = file->private_data; + if (dev == NULL) + return -ENODEV; + + /* decrement the count on our device */ + usb_autopm_put_interface(dev->interface); + kref_put(&dev->kref, lcd_delete); + return 0; +} + +static ssize_t lcd_read(struct file *file, char __user * buffer, + size_t count, loff_t *ppos) +{ + struct usb_lcd *dev; + int retval = 0; + int bytes_read; + + dev = 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 long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct usb_lcd *dev; + u16 bcdDevice; + char buf[30]; + + dev = file->private_data; + if (dev == NULL) + return -ENODEV; + + switch (cmd) { + case IOCTL_GET_HARD_VERSION: + mutex_lock(&lcd_mutex); + bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice); + sprintf(buf, "%1d%1d.%1d%1d", + (bcdDevice & 0xF000)>>12, + (bcdDevice & 0xF00)>>8, + (bcdDevice & 0xF0)>>4, + (bcdDevice & 0xF)); + mutex_unlock(&lcd_mutex); + if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0) + return -EFAULT; + break; + case IOCTL_GET_DRV_VERSION: + sprintf(buf, DRIVER_VERSION); + if (copy_to_user((void __user *)arg, buf, strlen(buf)) != 0) + return -EFAULT; + break; + default: + return -ENOTTY; + break; + } + + return 0; +} + +static void lcd_write_bulk_callback(struct urb *urb) +{ + struct usb_lcd *dev; + int status = urb->status; + + dev = urb->context; + + /* sync/async unlink faults aren't errors */ + if (status && + !(status == -ENOENT || + status == -ECONNRESET || + status == -ESHUTDOWN)) { + dev_dbg(&dev->interface->dev, + "nonzero write bulk status received: %d\n", 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 lcd_write(struct file *file, const char __user * user_buffer, + size_t count, loff_t *ppos) +{ + struct usb_lcd *dev; + int retval = 0, r; + struct urb *urb = NULL; + char *buf = NULL; + + dev = file->private_data; + + /* verify that we actually have some data to write */ + if (count == 0) + goto exit; + + r = down_interruptible(&dev->limit_sem); + if (r < 0) + return -EINTR; + + /* 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 err_no_buf; + } + + buf = usb_alloc_coherent(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, lcd_write_bulk_callback, dev); + urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + + usb_anchor_urb(urb, &dev->submitted); + + /* send the data out the bulk port */ + retval = usb_submit_urb(urb, GFP_KERNEL); + if (retval) { + dev_err(&dev->udev->dev, + "%s - failed submitting write urb, error %d\n", + __func__, retval); + goto error_unanchor; + } + + /* release our reference to this urb, + the USB core will eventually free it entirely */ + usb_free_urb(urb); + +exit: + return count; +error_unanchor: + usb_unanchor_urb(urb); +error: + usb_free_coherent(dev->udev, count, buf, urb->transfer_dma); + usb_free_urb(urb); +err_no_buf: + up(&dev->limit_sem); + return retval; +} + +static const struct file_operations lcd_fops = { + .owner = THIS_MODULE, + .read = lcd_read, + .write = lcd_write, + .open = lcd_open, + .unlocked_ioctl = lcd_ioctl, + .release = lcd_release, + .llseek = noop_llseek, +}; + +/* + * 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 lcd_class = { + .name = "lcd%d", + .fops = &lcd_fops, + .minor_base = USBLCD_MINOR, +}; + +static int lcd_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct usb_lcd *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 = kzalloc(sizeof(*dev), GFP_KERNEL); + if (dev == NULL) { + dev_err(&interface->dev, "Out of memory\n"); + goto error; + } + kref_init(&dev->kref); + sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES); + init_usb_anchor(&dev->submitted); + + dev->udev = usb_get_dev(interface_to_usbdev(interface)); + dev->interface = interface; + + if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) { + dev_warn(&interface->dev, "USBLCD model not supported.\n"); + retval = -ENODEV; + goto error; + } + + /* 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 && + usb_endpoint_is_bulk_in(endpoint)) { + /* we found a bulk in endpoint */ + 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) { + dev_err(&interface->dev, + "Could not allocate bulk_in_buffer\n"); + goto error; + } + } + + if (!dev->bulk_out_endpointAddr && + usb_endpoint_is_bulk_out(endpoint)) { + /* we found a bulk out endpoint */ + dev->bulk_out_endpointAddr = endpoint->bEndpointAddress; + } + } + if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) { + dev_err(&interface->dev, + "Could not find both bulk-in and bulk-out endpoints\n"); + 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, &lcd_class); + if (retval) { + /* something prevented us from registering this driver */ + dev_err(&interface->dev, + "Not able to get a minor for this device.\n"); + usb_set_intfdata(interface, NULL); + goto error; + } + + i = le16_to_cpu(dev->udev->descriptor.bcdDevice); + + dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found " + "at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8, + (i & 0xF0)>>4, (i & 0xF), dev->udev->devnum); + + /* let the user know what node this device is now attached to */ + dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n", + interface->minor); + return 0; + +error: + if (dev) + kref_put(&dev->kref, lcd_delete); + return retval; +} + +static void lcd_draw_down(struct usb_lcd *dev) +{ + int time; + + time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000); + if (!time) + usb_kill_anchored_urbs(&dev->submitted); +} + +static int lcd_suspend(struct usb_interface *intf, pm_message_t message) +{ + struct usb_lcd *dev = usb_get_intfdata(intf); + + if (!dev) + return 0; + lcd_draw_down(dev); + return 0; +} + +static int lcd_resume(struct usb_interface *intf) +{ + return 0; +} + +static void lcd_disconnect(struct usb_interface *interface) +{ + struct usb_lcd *dev; + int minor = interface->minor; + + mutex_lock(&open_disc_mutex); + dev = usb_get_intfdata(interface); + usb_set_intfdata(interface, NULL); + mutex_unlock(&open_disc_mutex); + + /* give back our minor */ + usb_deregister_dev(interface, &lcd_class); + + /* decrement our usage count */ + kref_put(&dev->kref, lcd_delete); + + dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor); +} + +static struct usb_driver lcd_driver = { + .name = "usblcd", + .probe = lcd_probe, + .disconnect = lcd_disconnect, + .suspend = lcd_suspend, + .resume = lcd_resume, + .id_table = id_table, + .supports_autosuspend = 1, +}; + +module_usb_driver(lcd_driver); + +MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>"); +MODULE_DESCRIPTION(DRIVER_VERSION); +MODULE_LICENSE("GPL"); |