diff options
Diffstat (limited to 'drivers/usb/serial/opticon.c')
-rw-r--r-- | drivers/usb/serial/opticon.c | 358 |
1 files changed, 358 insertions, 0 deletions
diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c new file mode 100644 index 0000000..cea326f --- /dev/null +++ b/drivers/usb/serial/opticon.c @@ -0,0 +1,358 @@ +/* + * Opticon USB barcode to serial driver + * + * Copyright (C) 2008 Greg Kroah-Hartman <gregkh@suse.de> + * Copyright (C) 2008 Novell Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/tty.h> +#include <linux/tty_driver.h> +#include <linux/tty_flip.h> +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/usb/serial.h> +#include <linux/uaccess.h> + +static int debug; + +static struct usb_device_id id_table[] = { + { USB_DEVICE(0x065a, 0x0009) }, + { }, +}; +MODULE_DEVICE_TABLE(usb, id_table); + +/* This structure holds all of the individual device information */ +struct opticon_private { + struct usb_device *udev; + struct usb_serial *serial; + struct usb_serial_port *port; + unsigned char *bulk_in_buffer; + struct urb *bulk_read_urb; + int buffer_size; + u8 bulk_address; + spinlock_t lock; /* protects the following flags */ + bool throttled; + bool actually_throttled; + bool rts; +}; + +static void opticon_bulk_callback(struct urb *urb) +{ + struct opticon_private *priv = urb->context; + unsigned char *data = urb->transfer_buffer; + struct usb_serial_port *port = priv->port; + int status = urb->status; + struct tty_struct *tty; + int result; + int available_room = 0; + int data_length; + + dbg("%s - port %d", __func__, port->number); + + switch (status) { + case 0: + /* success */ + break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + dbg("%s - urb shutting down with status: %d", + __func__, status); + return; + default: + dbg("%s - nonzero urb status received: %d", + __func__, status); + goto exit; + } + + usb_serial_debug_data(debug, &port->dev, __func__, urb->actual_length, + data); + + if (urb->actual_length > 2) { + data_length = urb->actual_length - 2; + + /* + * Data from the device comes with a 2 byte header: + * + * <0x00><0x00>data... + * This is real data to be sent to the tty layer + * <0x00><0x01)level + * This is a RTS level change, the third byte is the RTS + * value (0 for low, 1 for high). + */ + if ((data[0] == 0x00) && (data[1] == 0x00)) { + /* real data, send it to the tty layer */ + tty = tty_port_tty_get(&port->port); + if (tty) { + available_room = tty_buffer_request_room(tty, + data_length); + if (available_room) { + tty_insert_flip_string(tty, data, + available_room); + tty_flip_buffer_push(tty); + } + tty_kref_put(tty); + } + } else { + if ((data[0] == 0x00) && (data[1] == 0x01)) { + if (data[2] == 0x00) + priv->rts = false; + else + priv->rts = true; + /* FIXME change the RTS level */ + } else { + dev_dbg(&priv->udev->dev, + "Unknown data packet received from the device:" + " %2x %2x\n", + data[0], data[1]); + } + } + } else { + dev_dbg(&priv->udev->dev, + "Improper ammount of data received from the device, " + "%d bytes", urb->actual_length); + } + +exit: + spin_lock(&priv->lock); + + /* Continue trying to always read if we should */ + if (!priv->throttled) { + usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev, + usb_rcvbulkpipe(priv->udev, + priv->bulk_address), + priv->bulk_in_buffer, priv->buffer_size, + opticon_bulk_callback, priv); + result = usb_submit_urb(port->read_urb, GFP_ATOMIC); + if (result) + dev_err(&port->dev, + "%s - failed resubmitting read urb, error %d\n", + __func__, result); + } else + priv->actually_throttled = true; + spin_unlock(&priv->lock); +} + +static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port, + struct file *filp) +{ + struct opticon_private *priv = usb_get_serial_data(port->serial); + unsigned long flags; + int result = 0; + + dbg("%s - port %d", __func__, port->number); + + spin_lock_irqsave(&priv->lock, flags); + priv->throttled = false; + priv->actually_throttled = false; + priv->port = port; + spin_unlock_irqrestore(&priv->lock, flags); + + /* + * Force low_latency on so that our tty_push actually forces the data + * through, otherwise it is scheduled, and with high data rates (like + * with OHCI) data can get lost. + */ + if (tty) + tty->low_latency = 1; + + /* Start reading from the device */ + usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev, + usb_rcvbulkpipe(priv->udev, + priv->bulk_address), + priv->bulk_in_buffer, priv->buffer_size, + opticon_bulk_callback, priv); + result = usb_submit_urb(priv->bulk_read_urb, GFP_KERNEL); + if (result) + dev_err(&port->dev, + "%s - failed resubmitting read urb, error %d\n", + __func__, result); + return result; +} + +static void opticon_close(struct tty_struct *tty, struct usb_serial_port *port, + struct file *filp) +{ + struct opticon_private *priv = usb_get_serial_data(port->serial); + + dbg("%s - port %d", __func__, port->number); + + /* shutdown our urbs */ + usb_kill_urb(priv->bulk_read_urb); +} + +static void opticon_throttle(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + struct opticon_private *priv = usb_get_serial_data(port->serial); + unsigned long flags; + + dbg("%s - port %d", __func__, port->number); + spin_lock_irqsave(&priv->lock, flags); + priv->throttled = true; + spin_unlock_irqrestore(&priv->lock, flags); +} + + +static void opticon_unthrottle(struct tty_struct *tty) +{ + struct usb_serial_port *port = tty->driver_data; + struct opticon_private *priv = usb_get_serial_data(port->serial); + unsigned long flags; + int result; + + dbg("%s - port %d", __func__, port->number); + + spin_lock_irqsave(&priv->lock, flags); + priv->throttled = false; + priv->actually_throttled = false; + spin_unlock_irqrestore(&priv->lock, flags); + + priv->bulk_read_urb->dev = port->serial->dev; + result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC); + if (result) + dev_err(&port->dev, + "%s - failed submitting read urb, error %d\n", + __func__, result); +} + +static int opticon_startup(struct usb_serial *serial) +{ + struct opticon_private *priv; + struct usb_host_interface *intf; + int i; + int retval = -ENOMEM; + bool bulk_in_found = false; + + /* create our private serial structure */ + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (priv == NULL) { + dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__); + return -ENOMEM; + } + spin_lock_init(&priv->lock); + priv->serial = serial; + priv->port = serial->port[0]; + priv->udev = serial->dev; + + /* find our bulk endpoint */ + intf = serial->interface->altsetting; + for (i = 0; i < intf->desc.bNumEndpoints; ++i) { + struct usb_endpoint_descriptor *endpoint; + + endpoint = &intf->endpoint[i].desc; + if (!usb_endpoint_is_bulk_in(endpoint)) + continue; + + priv->bulk_read_urb = usb_alloc_urb(0, GFP_KERNEL); + if (!priv->bulk_read_urb) { + dev_err(&priv->udev->dev, "out of memory\n"); + goto error; + } + + priv->buffer_size = le16_to_cpu(endpoint->wMaxPacketSize) * 2; + priv->bulk_in_buffer = kmalloc(priv->buffer_size, GFP_KERNEL); + if (!priv->bulk_in_buffer) { + dev_err(&priv->udev->dev, "out of memory\n"); + goto error; + } + + priv->bulk_address = endpoint->bEndpointAddress; + + /* set up our bulk urb */ + usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev, + usb_rcvbulkpipe(priv->udev, + endpoint->bEndpointAddress), + priv->bulk_in_buffer, priv->buffer_size, + opticon_bulk_callback, priv); + + bulk_in_found = true; + break; + } + + if (!bulk_in_found) { + dev_err(&priv->udev->dev, + "Error - the proper endpoints were not found!\n"); + goto error; + } + + usb_set_serial_data(serial, priv); + return 0; + +error: + usb_free_urb(priv->bulk_read_urb); + kfree(priv->bulk_in_buffer); + kfree(priv); + return retval; +} + +static void opticon_shutdown(struct usb_serial *serial) +{ + struct opticon_private *priv = usb_get_serial_data(serial); + + dbg("%s", __func__); + + usb_kill_urb(priv->bulk_read_urb); + usb_free_urb(priv->bulk_read_urb); + kfree(priv->bulk_in_buffer); + kfree(priv); + usb_set_serial_data(serial, NULL); +} + + +static struct usb_driver opticon_driver = { + .name = "opticon", + .probe = usb_serial_probe, + .disconnect = usb_serial_disconnect, + .id_table = id_table, + .no_dynamic_id = 1, +}; + +static struct usb_serial_driver opticon_device = { + .driver = { + .owner = THIS_MODULE, + .name = "opticon", + }, + .id_table = id_table, + .usb_driver = &opticon_driver, + .num_ports = 1, + .attach = opticon_startup, + .open = opticon_open, + .close = opticon_close, + .shutdown = opticon_shutdown, + .throttle = opticon_throttle, + .unthrottle = opticon_unthrottle, +}; + +static int __init opticon_init(void) +{ + int retval; + + retval = usb_serial_register(&opticon_device); + if (retval) + return retval; + retval = usb_register(&opticon_driver); + if (retval) + usb_serial_deregister(&opticon_device); + return retval; +} + +static void __exit opticon_exit(void) +{ + usb_deregister(&opticon_driver); + usb_serial_deregister(&opticon_device); +} + +module_init(opticon_init); +module_exit(opticon_exit); +MODULE_LICENSE("GPL"); + +module_param(debug, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(debug, "Debug enabled or not"); |