/* * Opticon USB barcode to serial driver * * Copyright (C) 2011 Martin Jansen * Copyright (C) 2008 - 2009 Greg Kroah-Hartman * Copyright (C) 2008 - 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 #include #include #include #include #include #include #include #include #include #include #define CONTROL_RTS 0x02 #define RESEND_CTS_STATE 0x03 /* max number of write urbs in flight */ #define URB_UPPER_LIMIT 8 /* This driver works for the Opticon 1D barcode reader * an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */ #define DRIVER_DESC "Opticon USB barcode to serial driver (1D)" static const 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 urb *bulk_read_urb; spinlock_t lock; /* protects the following flags */ bool throttled; bool actually_throttled; bool rts; bool cts; int outstanding_urbs; }; static void opticon_read_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; struct opticon_private *priv = usb_get_serial_port_data(port); unsigned char *data = urb->transfer_buffer; int status = urb->status; struct tty_struct *tty; int result; int data_length; unsigned long flags; switch (status) { case 0: /* success */ break; case -ECONNRESET: case -ENOENT: case -ESHUTDOWN: /* this urb is terminated, clean up */ dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", __func__, status); return; default: dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", __func__, status); goto exit; } usb_serial_debug_data(&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 CTS level change, the third byte is the CTS * 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) { tty_insert_flip_string(tty, data + 2, data_length); tty_flip_buffer_push(tty); tty_kref_put(tty); } } else { if ((data[0] == 0x00) && (data[1] == 0x01)) { spin_lock_irqsave(&priv->lock, flags); /* CTS status information package */ if (data[2] == 0x00) priv->cts = false; else priv->cts = true; spin_unlock_irqrestore(&priv->lock, flags); } else { dev_dbg(&port->dev, "Unknown data packet received from the device:" " %2x %2x\n", data[0], data[1]); } } } else { dev_dbg(&port->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) { result = usb_submit_urb(priv->bulk_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 send_control_msg(struct usb_serial_port *port, u8 requesttype, u8 val) { struct usb_serial *serial = port->serial; int retval; u8 *buffer; buffer = kzalloc(1, GFP_KERNEL); if (!buffer) return -ENOMEM; buffer[0] = val; /* Send the message to the vendor control endpoint * of the connected device */ retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), requesttype, USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 0, 0, buffer, 1, 0); kfree(buffer); return retval; } static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port) { struct opticon_private *priv = usb_get_serial_port_data(port); unsigned long flags; int result = 0; spin_lock_irqsave(&priv->lock, flags); priv->throttled = false; priv->actually_throttled = false; priv->rts = false; spin_unlock_irqrestore(&priv->lock, flags); /* Clear RTS line */ send_control_msg(port, CONTROL_RTS, 0); /* clear the halt status of the enpoint */ usb_clear_halt(port->serial->dev, priv->bulk_read_urb->pipe); 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); /* Request CTS line state, sometimes during opening the current * CTS state can be missed. */ send_control_msg(port, RESEND_CTS_STATE, 1); return result; } static void opticon_close(struct usb_serial_port *port) { struct opticon_private *priv = usb_get_serial_port_data(port); /* shutdown our urbs */ usb_kill_urb(priv->bulk_read_urb); } static void opticon_write_control_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; struct opticon_private *priv = usb_get_serial_port_data(port); int status = urb->status; unsigned long flags; /* free up the transfer buffer, as usb_free_urb() does not do this */ kfree(urb->transfer_buffer); /* setup packet may be set if we're using it for writing */ kfree(urb->setup_packet); if (status) dev_dbg(&port->dev, "%s - non-zero urb status received: %d\n", __func__, status); spin_lock_irqsave(&priv->lock, flags); --priv->outstanding_urbs; spin_unlock_irqrestore(&priv->lock, flags); usb_serial_port_softint(port); } static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count) { struct opticon_private *priv = usb_get_serial_port_data(port); struct usb_serial *serial = port->serial; struct urb *urb; unsigned char *buffer; unsigned long flags; int status; struct usb_ctrlrequest *dr; spin_lock_irqsave(&priv->lock, flags); if (priv->outstanding_urbs > URB_UPPER_LIMIT) { spin_unlock_irqrestore(&priv->lock, flags); dev_dbg(&port->dev, "%s - write limit hit\n", __func__); return 0; } priv->outstanding_urbs++; spin_unlock_irqrestore(&priv->lock, flags); buffer = kmalloc(count, GFP_ATOMIC); if (!buffer) { dev_err(&port->dev, "out of memory\n"); count = -ENOMEM; goto error_no_buffer; } urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { dev_err(&port->dev, "no more free urbs\n"); count = -ENOMEM; goto error_no_urb; } memcpy(buffer, buf, count); usb_serial_debug_data(&port->dev, __func__, count, buffer); /* The conncected devices do not have a bulk write endpoint, * to transmit data to de barcode device the control endpoint is used */ dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); if (!dr) { dev_err(&port->dev, "out of memory\n"); count = -ENOMEM; goto error_no_dr; } dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT; dr->bRequest = 0x01; dr->wValue = 0; dr->wIndex = 0; dr->wLength = cpu_to_le16(count); usb_fill_control_urb(urb, serial->dev, usb_sndctrlpipe(serial->dev, 0), (unsigned char *)dr, buffer, count, opticon_write_control_callback, port); /* send it down the pipe */ status = usb_submit_urb(urb, GFP_ATOMIC); if (status) { dev_err(&port->dev, "%s - usb_submit_urb(write endpoint) failed status = %d\n", __func__, status); count = status; goto error; } /* we are done with this urb, so let the host driver * really free it when it is finished with it */ usb_free_urb(urb); return count; error: kfree(dr); error_no_dr: usb_free_urb(urb); error_no_urb: kfree(buffer); error_no_buffer: spin_lock_irqsave(&priv->lock, flags); --priv->outstanding_urbs; spin_unlock_irqrestore(&priv->lock, flags); return count; } static int opticon_write_room(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct opticon_private *priv = usb_get_serial_port_data(port); unsigned long flags; /* * We really can take almost anything the user throws at us * but let's pick a nice big number to tell the tty * layer that we have lots of free space, unless we don't. */ spin_lock_irqsave(&priv->lock, flags); if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) { spin_unlock_irqrestore(&priv->lock, flags); dev_dbg(&port->dev, "%s - write limit hit\n", __func__); return 0; } spin_unlock_irqrestore(&priv->lock, flags); return 2048; } static void opticon_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct opticon_private *priv = usb_get_serial_port_data(port); unsigned long flags; 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_port_data(port); unsigned long flags; int result, was_throttled; spin_lock_irqsave(&priv->lock, flags); priv->throttled = false; was_throttled = priv->actually_throttled; priv->actually_throttled = false; spin_unlock_irqrestore(&priv->lock, flags); if (was_throttled) { 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_tiocmget(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct opticon_private *priv = usb_get_serial_port_data(port); unsigned long flags; int result = 0; spin_lock_irqsave(&priv->lock, flags); if (priv->rts) result |= TIOCM_RTS; if (priv->cts) result |= TIOCM_CTS; spin_unlock_irqrestore(&priv->lock, flags); dev_dbg(&port->dev, "%s - %x\n", __func__, result); return result; } static int opticon_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) { struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; struct opticon_private *priv = usb_get_serial_port_data(port); unsigned long flags; bool rts; bool changed = false; int ret; /* We only support RTS so we only handle that */ spin_lock_irqsave(&priv->lock, flags); rts = priv->rts; if (set & TIOCM_RTS) priv->rts = true; if (clear & TIOCM_RTS) priv->rts = false; changed = rts ^ priv->rts; spin_unlock_irqrestore(&priv->lock, flags); if (!changed) return 0; /* Send the new RTS state to the connected device */ mutex_lock(&serial->disc_mutex); if (!serial->disconnected) ret = send_control_msg(port, CONTROL_RTS, !rts); else ret = -ENODEV; mutex_unlock(&serial->disc_mutex); return ret; } static int get_serial_info(struct usb_serial_port *port, struct serial_struct __user *serial) { struct serial_struct tmp; if (!serial) return -EFAULT; memset(&tmp, 0x00, sizeof(tmp)); /* fake emulate a 16550 uart to make userspace code happy */ tmp.type = PORT_16550A; tmp.line = port->serial->minor; tmp.port = 0; tmp.irq = 0; tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ; tmp.xmit_fifo_size = 1024; tmp.baud_base = 9600; tmp.close_delay = 5*HZ; tmp.closing_wait = 30*HZ; if (copy_to_user(serial, &tmp, sizeof(*serial))) return -EFAULT; return 0; } static int opticon_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { struct usb_serial_port *port = tty->driver_data; dev_dbg(&port->dev, "%s - port %d, cmd = 0x%x\n", __func__, port->number, cmd); switch (cmd) { case TIOCGSERIAL: return get_serial_info(port, (struct serial_struct __user *)arg); } return -ENOIOCTLCMD; } static int opticon_startup(struct usb_serial *serial) { if (!serial->num_bulk_in) { dev_err(&serial->dev->dev, "no bulk in endpoint\n"); return -ENODEV; } return 0; } static int opticon_port_probe(struct usb_serial_port *port) { struct opticon_private *priv; priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; spin_lock_init(&priv->lock); priv->bulk_read_urb = port->read_urbs[0]; usb_set_serial_port_data(port, priv); return 0; } static int opticon_port_remove(struct usb_serial_port *port) { struct opticon_private *priv = usb_get_serial_port_data(port); kfree(priv); return 0; } static int opticon_suspend(struct usb_serial *serial, pm_message_t message) { struct opticon_private *priv; priv = usb_get_serial_port_data(serial->port[0]); usb_kill_urb(priv->bulk_read_urb); return 0; } static int opticon_resume(struct usb_serial *serial) { struct usb_serial_port *port = serial->port[0]; struct opticon_private *priv = usb_get_serial_port_data(port); int result; mutex_lock(&port->port.mutex); /* This is protected by the port mutex against close/open */ if (test_bit(ASYNCB_INITIALIZED, &port->port.flags)) result = usb_submit_urb(priv->bulk_read_urb, GFP_NOIO); else result = 0; mutex_unlock(&port->port.mutex); return result; } static struct usb_serial_driver opticon_device = { .driver = { .owner = THIS_MODULE, .name = "opticon", }, .id_table = id_table, .num_ports = 1, .bulk_in_size = 256, .attach = opticon_startup, .port_probe = opticon_port_probe, .port_remove = opticon_port_remove, .open = opticon_open, .close = opticon_close, .write = opticon_write, .write_room = opticon_write_room, .throttle = opticon_throttle, .unthrottle = opticon_unthrottle, .ioctl = opticon_ioctl, .tiocmget = opticon_tiocmget, .tiocmset = opticon_tiocmset, .suspend = opticon_suspend, .resume = opticon_resume, .read_bulk_callback = opticon_read_bulk_callback, }; static struct usb_serial_driver * const serial_drivers[] = { &opticon_device, NULL }; module_usb_serial_driver(serial_drivers, id_table); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL");