|  | /* | 
|  | * Symbol USB barcode to serial driver | 
|  | * | 
|  | * Copyright (C) 2009 Greg Kroah-Hartman <gregkh@suse.de> | 
|  | * Copyright (C) 2009 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/slab.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 const struct usb_device_id id_table[] = { | 
|  | { USB_DEVICE(0x05e0, 0x0600) }, | 
|  | { }, | 
|  | }; | 
|  | MODULE_DEVICE_TABLE(usb, id_table); | 
|  |  | 
|  | /* This structure holds all of the individual device information */ | 
|  | struct symbol_private { | 
|  | struct usb_device *udev; | 
|  | struct usb_serial *serial; | 
|  | struct usb_serial_port *port; | 
|  | unsigned char *int_buffer; | 
|  | struct urb *int_urb; | 
|  | int buffer_size; | 
|  | u8 bInterval; | 
|  | u8 int_address; | 
|  | spinlock_t lock;	/* protects the following flags */ | 
|  | bool throttled; | 
|  | bool actually_throttled; | 
|  | bool rts; | 
|  | }; | 
|  |  | 
|  | static void symbol_int_callback(struct urb *urb) | 
|  | { | 
|  | struct symbol_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 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 > 1) { | 
|  | data_length = urb->actual_length - 1; | 
|  |  | 
|  | /* | 
|  | * Data from the device comes with a 1 byte header: | 
|  | * | 
|  | * <size of data>data... | 
|  | * 	This is real data to be sent to the tty layer | 
|  | * we pretty much just ignore the size and send everything | 
|  | * else to the tty layer. | 
|  | */ | 
|  | tty = tty_port_tty_get(&port->port); | 
|  | if (tty) { | 
|  | tty_insert_flip_string(tty, &data[1], data_length); | 
|  | tty_flip_buffer_push(tty); | 
|  | tty_kref_put(tty); | 
|  | } | 
|  | } else { | 
|  | dev_dbg(&priv->udev->dev, | 
|  | "Improper amount 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_int_urb(priv->int_urb, priv->udev, | 
|  | usb_rcvintpipe(priv->udev, | 
|  | priv->int_address), | 
|  | priv->int_buffer, priv->buffer_size, | 
|  | symbol_int_callback, priv, priv->bInterval); | 
|  | result = usb_submit_urb(priv->int_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 symbol_open(struct tty_struct *tty, struct usb_serial_port *port) | 
|  | { | 
|  | struct symbol_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); | 
|  |  | 
|  | /* Start reading from the device */ | 
|  | usb_fill_int_urb(priv->int_urb, priv->udev, | 
|  | usb_rcvintpipe(priv->udev, priv->int_address), | 
|  | priv->int_buffer, priv->buffer_size, | 
|  | symbol_int_callback, priv, priv->bInterval); | 
|  | result = usb_submit_urb(priv->int_urb, GFP_KERNEL); | 
|  | if (result) | 
|  | dev_err(&port->dev, | 
|  | "%s - failed resubmitting read urb, error %d\n", | 
|  | __func__, result); | 
|  | return result; | 
|  | } | 
|  |  | 
|  | static void symbol_close(struct usb_serial_port *port) | 
|  | { | 
|  | struct symbol_private *priv = usb_get_serial_data(port->serial); | 
|  |  | 
|  | dbg("%s - port %d", __func__, port->number); | 
|  |  | 
|  | /* shutdown our urbs */ | 
|  | usb_kill_urb(priv->int_urb); | 
|  | } | 
|  |  | 
|  | static void symbol_throttle(struct tty_struct *tty) | 
|  | { | 
|  | struct usb_serial_port *port = tty->driver_data; | 
|  | struct symbol_private *priv = usb_get_serial_data(port->serial); | 
|  |  | 
|  | dbg("%s - port %d", __func__, port->number); | 
|  | spin_lock_irq(&priv->lock); | 
|  | priv->throttled = true; | 
|  | spin_unlock_irq(&priv->lock); | 
|  | } | 
|  |  | 
|  | static void symbol_unthrottle(struct tty_struct *tty) | 
|  | { | 
|  | struct usb_serial_port *port = tty->driver_data; | 
|  | struct symbol_private *priv = usb_get_serial_data(port->serial); | 
|  | int result; | 
|  | bool was_throttled; | 
|  |  | 
|  | dbg("%s - port %d", __func__, port->number); | 
|  |  | 
|  | spin_lock_irq(&priv->lock); | 
|  | priv->throttled = false; | 
|  | was_throttled = priv->actually_throttled; | 
|  | priv->actually_throttled = false; | 
|  | spin_unlock_irq(&priv->lock); | 
|  |  | 
|  | priv->int_urb->dev = port->serial->dev; | 
|  | if (was_throttled) { | 
|  | result = usb_submit_urb(priv->int_urb, GFP_KERNEL); | 
|  | if (result) | 
|  | dev_err(&port->dev, | 
|  | "%s - failed submitting read urb, error %d\n", | 
|  | __func__, result); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int symbol_startup(struct usb_serial *serial) | 
|  | { | 
|  | struct symbol_private *priv; | 
|  | struct usb_host_interface *intf; | 
|  | int i; | 
|  | int retval = -ENOMEM; | 
|  | bool int_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 interrupt 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_int_in(endpoint)) | 
|  | continue; | 
|  |  | 
|  | priv->int_urb = usb_alloc_urb(0, GFP_KERNEL); | 
|  | if (!priv->int_urb) { | 
|  | dev_err(&priv->udev->dev, "out of memory\n"); | 
|  | goto error; | 
|  | } | 
|  |  | 
|  | priv->buffer_size = le16_to_cpu(endpoint->wMaxPacketSize) * 2; | 
|  | priv->int_buffer = kmalloc(priv->buffer_size, GFP_KERNEL); | 
|  | if (!priv->int_buffer) { | 
|  | dev_err(&priv->udev->dev, "out of memory\n"); | 
|  | goto error; | 
|  | } | 
|  |  | 
|  | priv->int_address = endpoint->bEndpointAddress; | 
|  | priv->bInterval = endpoint->bInterval; | 
|  |  | 
|  | /* set up our int urb */ | 
|  | usb_fill_int_urb(priv->int_urb, priv->udev, | 
|  | usb_rcvintpipe(priv->udev, | 
|  | endpoint->bEndpointAddress), | 
|  | priv->int_buffer, priv->buffer_size, | 
|  | symbol_int_callback, priv, priv->bInterval); | 
|  |  | 
|  | int_in_found = true; | 
|  | break; | 
|  | } | 
|  |  | 
|  | if (!int_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->int_urb); | 
|  | kfree(priv->int_buffer); | 
|  | kfree(priv); | 
|  | return retval; | 
|  | } | 
|  |  | 
|  | static void symbol_disconnect(struct usb_serial *serial) | 
|  | { | 
|  | struct symbol_private *priv = usb_get_serial_data(serial); | 
|  |  | 
|  | dbg("%s", __func__); | 
|  |  | 
|  | usb_kill_urb(priv->int_urb); | 
|  | usb_free_urb(priv->int_urb); | 
|  | } | 
|  |  | 
|  | static void symbol_release(struct usb_serial *serial) | 
|  | { | 
|  | struct symbol_private *priv = usb_get_serial_data(serial); | 
|  |  | 
|  | dbg("%s", __func__); | 
|  |  | 
|  | kfree(priv->int_buffer); | 
|  | kfree(priv); | 
|  | } | 
|  |  | 
|  | static struct usb_driver symbol_driver = { | 
|  | .name =			"symbol", | 
|  | .probe =		usb_serial_probe, | 
|  | .disconnect =		usb_serial_disconnect, | 
|  | .id_table =		id_table, | 
|  | .no_dynamic_id = 	1, | 
|  | }; | 
|  |  | 
|  | static struct usb_serial_driver symbol_device = { | 
|  | .driver = { | 
|  | .owner =	THIS_MODULE, | 
|  | .name =		"symbol", | 
|  | }, | 
|  | .id_table =		id_table, | 
|  | .usb_driver = 		&symbol_driver, | 
|  | .num_ports =		1, | 
|  | .attach =		symbol_startup, | 
|  | .open =			symbol_open, | 
|  | .close =		symbol_close, | 
|  | .disconnect =		symbol_disconnect, | 
|  | .release =		symbol_release, | 
|  | .throttle = 		symbol_throttle, | 
|  | .unthrottle =		symbol_unthrottle, | 
|  | }; | 
|  |  | 
|  | static int __init symbol_init(void) | 
|  | { | 
|  | int retval; | 
|  |  | 
|  | retval = usb_serial_register(&symbol_device); | 
|  | if (retval) | 
|  | return retval; | 
|  | retval = usb_register(&symbol_driver); | 
|  | if (retval) | 
|  | usb_serial_deregister(&symbol_device); | 
|  | return retval; | 
|  | } | 
|  |  | 
|  | static void __exit symbol_exit(void) | 
|  | { | 
|  | usb_deregister(&symbol_driver); | 
|  | usb_serial_deregister(&symbol_device); | 
|  | } | 
|  |  | 
|  | module_init(symbol_init); | 
|  | module_exit(symbol_exit); | 
|  | MODULE_LICENSE("GPL"); | 
|  |  | 
|  | module_param(debug, bool, S_IRUGO | S_IWUSR); | 
|  | MODULE_PARM_DESC(debug, "Debug enabled or not"); |