USB: opticon: add rts and cts support (309a0579) · Commits · git / linux-net

drivers/usb/serial/opticon.c

+112 −44

Original line number	Diff line number	Diff line
		/*
		* Opticon USB barcode to serial driver
		*
		* Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
		* Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
		* Copyright (C) 2008 - 2009 Novell Inc.
		*
		@@ -21,6 +22,16 @@
		#include <linux/usb/serial.h>
		#include <linux/uaccess.h>

		#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 int debug;

		static const struct usb_device_id id_table[] = {
		@@ -42,13 +53,13 @@ struct opticon_private {
		bool throttled;
		bool actually_throttled;
		bool rts;
		bool cts;
		int outstanding_urbs;
		};

		/* max number of write urbs in flight */
		#define URB_UPPER_LIMIT 4

		static void opticon_bulk_callback(struct urb *urb)

		static void opticon_read_bulk_callback(struct urb *urb)
		{
		struct opticon_private *priv = urb->context;
		unsigned char *data = urb->transfer_buffer;
		@@ -57,6 +68,7 @@ static void opticon_bulk_callback(struct urb *urb)
		struct tty_struct *tty;
		int result;
		int data_length;
		unsigned long flags;

		dbg("%s - port %d", __func__, port->number);

		@@ -89,7 +101,7 @@ static void opticon_bulk_callback(struct urb *urb)
		* <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
		* 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)) {
		@@ -103,10 +115,13 @@ static void opticon_bulk_callback(struct urb *urb)
		}
		} else {
		if ((data[0] == 0x00) && (data[1] == 0x01)) {
		spin_lock_irqsave(&priv->lock, flags);
		/* CTS status infomation package */
		if (data[2] == 0x00)
		priv->rts = false;
		priv->cts = false;
		else
		priv->rts = true;
		priv->cts = true;
		spin_unlock_irqrestore(&priv->lock, flags);
		} else {
		dev_dbg(&priv->udev->dev,
		"Unknown data packet received from the device:"
		@@ -129,7 +144,7 @@ static void opticon_bulk_callback(struct urb *urb)
		usb_rcvbulkpipe(priv->udev,
		priv->bulk_address),
		priv->bulk_in_buffer, priv->buffer_size,
		opticon_bulk_callback, priv);
		opticon_read_bulk_callback, priv);
		result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
		if (result)
		dev_err(&port->dev,
		@@ -140,6 +155,24 @@ static void opticon_bulk_callback(struct urb *urb)
		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[2];

		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);

		return retval;
		}

		static int opticon_open(struct tty_struct tty, struct usb_serial_port port)
		{
		struct opticon_private *priv = usb_get_serial_data(port->serial);
		@@ -152,19 +185,30 @@ static int opticon_open(struct tty_struct tty, struct usb_serial_port port)
		priv->throttled = false;
		priv->actually_throttled = false;
		priv->port = port;
		priv->rts = false;
		spin_unlock_irqrestore(&priv->lock, flags);

		/* Start reading from the device */
		/* Clear RTS line */
		send_control_msg(port, CONTROL_RTS, 0);

		/* Setup the read URB and 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);
		opticon_read_bulk_callback, priv);

		/* clear the halt status of the enpoint */
		usb_clear_halt(priv->udev, 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;
		}

		@@ -178,7 +222,7 @@ static void opticon_close(struct usb_serial_port *port)
		usb_kill_urb(priv->bulk_read_urb);
		}

		static void opticon_write_bulk_callback(struct urb *urb)
		static void opticon_write_control_callback(struct urb *urb)
		{
		struct opticon_private *priv = urb->context;
		int status = urb->status;
		@@ -210,6 +254,7 @@ static int opticon_write(struct tty_struct tty, struct usb_serial_port port,
		unsigned char *buffer;
		unsigned long flags;
		int status;
		struct usb_ctrlrequest *dr;

		dbg("%s - port %d", __func__, port->number);

		@@ -226,6 +271,7 @@ static int opticon_write(struct tty_struct tty, struct usb_serial_port port,
		if (!buffer) {
		dev_err(&port->dev, "out of memory\n");
		count = -ENOMEM;

		goto error_no_buffer;
		}

		@@ -240,14 +286,8 @@ static int opticon_write(struct tty_struct tty, struct usb_serial_port port,

		usb_serial_debug_data(debug, &port->dev, __func__, count, buffer);

		if (port->bulk_out_endpointAddress) {
		usb_fill_bulk_urb(urb, serial->dev,
		usb_sndbulkpipe(serial->dev,
		port->bulk_out_endpointAddress),
		buffer, count, opticon_write_bulk_callback, priv);
		} else {
		struct usb_ctrlrequest *dr;

		/* 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)
		return -ENOMEM;
		@@ -261,14 +301,13 @@ static int opticon_write(struct tty_struct tty, struct usb_serial_port port,
		usb_fill_control_urb(urb, serial->dev,
		usb_sndctrlpipe(serial->dev, 0),
		(unsigned char *)dr, buffer, count,
		opticon_write_bulk_callback, priv);
		}
		opticon_write_control_callback, priv);

		/* send it down the pipe */
		status = usb_submit_urb(urb, GFP_ATOMIC);
		if (status) {
		dev_err(&port->dev,
		"%s - usb_submit_urb(write bulk) failed with status = %d\n",
		"%s - usb_submit_urb(write endpoint) failed status = %d\n",
		__func__, status);
		count = status;
		goto error;
		@@ -360,16 +399,49 @@ static int opticon_tiocmget(struct tty_struct tty, struct file file)
		int result = 0;

		dbg("%s - port %d", __func__, port->number);
		if (!usb_get_intfdata(port->serial->interface))
		return -ENODEV;

		spin_lock_irqsave(&priv->lock, flags);
		if (priv->rts)
		result = TIOCM_RTS;
		result \|= TIOCM_RTS;
		if (priv->cts)
		result \|= TIOCM_CTS;
		spin_unlock_irqrestore(&priv->lock, flags);

		dbg("%s - %x", __func__, result);
		return result;
		}

		static int opticon_tiocmset(struct tty_struct tty, struct file file,
		unsigned int set, unsigned int clear)
		{
		struct usb_serial_port *port = tty->driver_data;
		struct opticon_private *priv = usb_get_serial_data(port->serial);
		unsigned long flags;
		bool rts;
		bool changed = false;

		if (!usb_get_intfdata(port->serial->interface))
		return -ENODEV;
		/* 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 */
		return send_control_msg(port, CONTROL_RTS, !rts);
		}

		static int get_serial_info(struct opticon_private *priv,
		struct serial_struct __user *serial)
		{
		@@ -431,6 +503,7 @@ static int opticon_startup(struct usb_serial *serial)
		priv->serial = serial;
		priv->port = serial->port[0];
		priv->udev = serial->dev;
		priv->outstanding_urbs = 0; /* Init the outstanding urbs */

		/* find our bulk endpoint */
		intf = serial->interface->altsetting;
		@@ -456,13 +529,6 @@ static int opticon_startup(struct usb_serial *serial)

		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;
		}
		@@ -558,6 +624,7 @@ static struct usb_serial_driver opticon_device = {
		.unthrottle = opticon_unthrottle,
		.ioctl = opticon_ioctl,
		.tiocmget = opticon_tiocmget,
		.tiocmset = opticon_tiocmset,
		};

		static int __init opticon_init(void)
		@@ -581,6 +648,7 @@ static void __exit opticon_exit(void)

		module_init(opticon_init);
		module_exit(opticon_exit);
		MODULE_DESCRIPTION(DRIVER_DESC);
		MODULE_LICENSE("GPL");

		module_param(debug, bool, S_IRUGO \| S_IWUSR);