[deliverable/linux.git] / drivers / usb / serial / opticon.c

/*
 * Opticon USB barcode to serial driver
 *
 * Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
 * 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.
 *
 *	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/tty.h>
#include <linux/tty_driver.h>
#include <linux/slab.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/module.h>
#include <linux/usb.h>
#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 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 {
	spinlock_t lock;	/* protects the following flags */
	bool rts;
	bool cts;
	int outstanding_urbs;
};


static void opticon_process_data_packet(struct usb_serial_port *port,
					const unsigned char *buf, size_t len)
{
	tty_insert_flip_string(&port->port, buf, len);
	tty_flip_buffer_push(&port->port);
}

static void opticon_process_status_packet(struct usb_serial_port *port,
					const unsigned char *buf, size_t len)
{
	struct opticon_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);
	if (buf[0] == 0x00)
		priv->cts = false;
	else
		priv->cts = true;
	spin_unlock_irqrestore(&priv->lock, flags);
}

static void opticon_process_read_urb(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	const unsigned char *hdr = urb->transfer_buffer;
	const unsigned char *data = hdr + 2;
	size_t data_len = urb->actual_length - 2;

	if (urb->actual_length <= 2) {
		dev_dbg(&port->dev, "malformed packet received: %d bytes\n",
							urb->actual_length);
		return;
	}
	/*
	 * 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 ((hdr[0] == 0x00) && (hdr[1] == 0x00)) {
		opticon_process_data_packet(port, data, data_len);
	} else if ((hdr[0] == 0x00) && (hdr[1] == 0x01)) {
		opticon_process_status_packet(port, data, data_len);
	} else {
		dev_dbg(&port->dev, "unknown packet received: %02x %02x\n",
							hdr[0], hdr[1]);
	}
}

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);

	if (retval < 0)
		return retval;

	return 0;
}

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 res;

	spin_lock_irqsave(&priv->lock, flags);
	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 endpoint */
	usb_clear_halt(port->serial->dev, port->read_urb->pipe);

	res = usb_serial_generic_open(tty, port);
	if (!res)
		return res;

	/* Request CTS line state, sometimes during opening the current
	 * CTS state can be missed. */
	send_control_msg(port, RESEND_CTS_STATE, 1);

	return res;
}

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) {
		count = -ENOMEM;
		goto error_no_buffer;
	}

	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb) {
		count = -ENOMEM;
		goto error_no_urb;
	}

	memcpy(buffer, buf, count);

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

	/* The connected 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_ATOMIC);
	if (!dr) {
		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 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 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;

	ret = send_control_msg(port, CONTROL_RTS, !rts);
	if (ret)
		return usb_translate_errors(ret);

	return 0;
}

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->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;

	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);

	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 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,
	.write =		opticon_write,
	.write_room = 		opticon_write_room,
	.throttle =		usb_serial_generic_throttle,
	.unthrottle =		usb_serial_generic_unthrottle,
	.ioctl =		opticon_ioctl,
	.tiocmget =		opticon_tiocmget,
	.tiocmset =		opticon_tiocmset,
	.process_read_urb =	opticon_process_read_urb,
};

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");
Commit	Line	Data
57262b82 GKH	1	/*
	2	* Opticon USB barcode to serial driver
	3	*
7a6ee2b0	4	* Copyright (C) 2011 - 2012 Johan Hovold <jhovold@gmail.com>
309a0579	5	* Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
648d4e16 GKH	6	* Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
648d4e16 GKH	7	* Copyright (C) 2008 - 2009 Novell Inc.
57262b82 GKH	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License version
	11	* 2 as published by the Free Software Foundation.
	12	*/
	13
	14	#include <linux/kernel.h>
57262b82 GKH	15	#include <linux/tty.h>
57262b82 GKH	16	#include <linux/tty_driver.h>
5a0e3ad6	17	#include <linux/slab.h>
57262b82	18	#include <linux/tty_flip.h>
faac64ad	19	#include <linux/serial.h>
57262b82 GKH	20	#include <linux/module.h>
	21	#include <linux/usb.h>
	22	#include <linux/usb/serial.h>
	23	#include <linux/uaccess.h>
	24
309a0579 MJ	25	#define CONTROL_RTS 0x02
	26	#define RESEND_CTS_STATE 0x03
	27
	28	/* max number of write urbs in flight */
	29	#define URB_UPPER_LIMIT 8
	30
	31	/* This driver works for the Opticon 1D barcode reader
	32	* an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
	33	#define DRIVER_DESC "Opticon USB barcode to serial driver (1D)"
	34
7d40d7e8	35	static const struct usb_device_id id_table[] = {
57262b82 GKH	36	{ USB_DEVICE(0x065a, 0x0009) },
	37	{ },
	38	};
	39	MODULE_DEVICE_TABLE(usb, id_table);
	40
	41	/* This structure holds all of the individual device information */
	42	struct opticon_private {
57262b82	43	spinlock_t lock; /* protects the following flags */
57262b82	44	bool rts;
309a0579	45	bool cts;
648d4e16	46	int outstanding_urbs;
57262b82 GKH	47	};
57262b82 GKH	48
648d4e16	49
32802077 JH	50	static void opticon_process_data_packet(struct usb_serial_port *port,
	51	const unsigned char *buf, size_t len)
	52	{
05c7cd39	53	tty_insert_flip_string(&port->port, buf, len);
2e124b4a	54	tty_flip_buffer_push(&port->port);
32802077 JH	55	}
	56
	57	static void opticon_process_status_packet(struct usb_serial_port *port,
	58	const unsigned char *buf, size_t len)
	59	{
	60	struct opticon_private *priv = usb_get_serial_port_data(port);
	61	unsigned long flags;
	62
	63	spin_lock_irqsave(&priv->lock, flags);
	64	if (buf[0] == 0x00)
	65	priv->cts = false;
	66	else
	67	priv->cts = true;
	68	spin_unlock_irqrestore(&priv->lock, flags);
	69	}
	70
	71	static void opticon_process_read_urb(struct urb *urb)
	72	{
	73	struct usb_serial_port *port = urb->context;
	74	const unsigned char *hdr = urb->transfer_buffer;
	75	const unsigned char *data = hdr + 2;
	76	size_t data_len = urb->actual_length - 2;
	77
	78	if (urb->actual_length <= 2) {
	79	dev_dbg(&port->dev, "malformed packet received: %d bytes\n",
	80	urb->actual_length);
	81	return;
	82	}
	83	/*
	84	* Data from the device comes with a 2 byte header:
	85	*
	86	* <0x00><0x00>data...
	87	* This is real data to be sent to the tty layer
	88	* <0x00><0x01>level
	89	* This is a CTS level change, the third byte is the CTS
	90	* value (0 for low, 1 for high).
	91	*/
	92	if ((hdr[0] == 0x00) && (hdr[1] == 0x00)) {
	93	opticon_process_data_packet(port, data, data_len);
	94	} else if ((hdr[0] == 0x00) && (hdr[1] == 0x01)) {
	95	opticon_process_status_packet(port, data, data_len);
	96	} else {
	97	dev_dbg(&port->dev, "unknown packet received: %02x %02x\n",
	98	hdr[0], hdr[1]);
	99	}
	100	}
309a0579	101
309a0579 MJ	102	static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
	103	u8 val)
	104	{
	105	struct usb_serial *serial = port->serial;
	106	int retval;
ea0dbebf JH	107	u8 *buffer;
	108
	109	buffer = kzalloc(1, GFP_KERNEL);
	110	if (!buffer)
	111	return -ENOMEM;
309a0579 MJ	112
	113	buffer[0] = val;
	114	/* Send the message to the vendor control endpoint
	115	* of the connected device */
	116	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
	117	requesttype,
	118	USB_DIR_OUT\|USB_TYPE_VENDOR\|USB_RECIP_INTERFACE,
	119	0, 0, buffer, 1, 0);
ea0dbebf	120	kfree(buffer);
309a0579	121
94c51dca JH	122	if (retval < 0)
	123	return retval;
	124
	125	return 0;
309a0579 MJ	126	}
309a0579 MJ	127
a509a7e4	128	static int opticon_open(struct tty_struct tty, struct usb_serial_port port)
57262b82	129	{
70d25eee	130	struct opticon_private *priv = usb_get_serial_port_data(port);
57262b82	131	unsigned long flags;
7a6ee2b0	132	int res;
57262b82	133
57262b82	134	spin_lock_irqsave(&priv->lock, flags);
309a0579	135	priv->rts = false;
57262b82 GKH	136	spin_unlock_irqrestore(&priv->lock, flags);
57262b82 GKH	137
309a0579 MJ	138	/* Clear RTS line */
	139	send_control_msg(port, CONTROL_RTS, 0);
	140
cd8c5053	141	/* clear the halt status of the endpoint */
7a6ee2b0 JH	142	usb_clear_halt(port->serial->dev, port->read_urb->pipe);
	143
	144	res = usb_serial_generic_open(tty, port);
	145	if (!res)
	146	return res;
309a0579	147
309a0579 MJ	148	/* Request CTS line state, sometimes during opening the current
	149	* CTS state can be missed. */
	150	send_control_msg(port, RESEND_CTS_STATE, 1);
57262b82	151
7a6ee2b0	152	return res;
57262b82 GKH	153	}
57262b82 GKH	154
309a0579	155	static void opticon_write_control_callback(struct urb *urb)
648d4e16	156	{
e32d82bc JH	157	struct usb_serial_port *port = urb->context;
e32d82bc JH	158	struct opticon_private *priv = usb_get_serial_port_data(port);
648d4e16 GKH	159	int status = urb->status;
	160	unsigned long flags;
	161
	162	/* free up the transfer buffer, as usb_free_urb() does not do this */
	163	kfree(urb->transfer_buffer);
	164
0d930e51 AZ	165	/* setup packet may be set if we're using it for writing */
	166	kfree(urb->setup_packet);
	167
648d4e16	168	if (status)
e32d82bc	169	dev_dbg(&port->dev,
e29a7738	170	"%s - non-zero urb status received: %d\n",
d44d9ab7	171	__func__, status);
648d4e16 GKH	172
	173	spin_lock_irqsave(&priv->lock, flags);
	174	--priv->outstanding_urbs;
	175	spin_unlock_irqrestore(&priv->lock, flags);
	176
e32d82bc	177	usb_serial_port_softint(port);
648d4e16 GKH	178	}
	179
	180	static int opticon_write(struct tty_struct tty, struct usb_serial_port port,
	181	const unsigned char *buf, int count)
	182	{
70d25eee	183	struct opticon_private *priv = usb_get_serial_port_data(port);
648d4e16 GKH	184	struct usb_serial *serial = port->serial;
	185	struct urb *urb;
	186	unsigned char *buffer;
	187	unsigned long flags;
	188	int status;
309a0579	189	struct usb_ctrlrequest *dr;
648d4e16	190
648d4e16 GKH	191	spin_lock_irqsave(&priv->lock, flags);
	192	if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
	193	spin_unlock_irqrestore(&priv->lock, flags);
d44d9ab7	194	dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
648d4e16 GKH	195	return 0;
	196	}
	197	priv->outstanding_urbs++;
	198	spin_unlock_irqrestore(&priv->lock, flags);
	199
	200	buffer = kmalloc(count, GFP_ATOMIC);
	201	if (!buffer) {
648d4e16 GKH	202	count = -ENOMEM;
	203	goto error_no_buffer;
	204	}
	205
	206	urb = usb_alloc_urb(0, GFP_ATOMIC);
	207	if (!urb) {
648d4e16 GKH	208	count = -ENOMEM;
	209	goto error_no_urb;
	210	}
	211
	212	memcpy(buffer, buf, count);
	213
59d33f2f	214	usb_serial_debug_data(&port->dev, __func__, count, buffer);
648d4e16	215
cd8c5053	216	/* The connected devices do not have a bulk write endpoint,
309a0579	217	* to transmit data to de barcode device the control endpoint is used */
e681286d	218	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
b0795bbf	219	if (!dr) {
b0795bbf	220	count = -ENOMEM;
acbf0e52	221	goto error_no_dr;
b0795bbf	222	}
309a0579 MJ	223
	224	dr->bRequestType = USB_TYPE_VENDOR \| USB_RECIP_INTERFACE \| USB_DIR_OUT;
	225	dr->bRequest = 0x01;
	226	dr->wValue = 0;
	227	dr->wIndex = 0;
	228	dr->wLength = cpu_to_le16(count);
	229
	230	usb_fill_control_urb(urb, serial->dev,
	231	usb_sndctrlpipe(serial->dev, 0),
	232	(unsigned char *)dr, buffer, count,
e32d82bc	233	opticon_write_control_callback, port);
648d4e16 GKH	234
	235	/* send it down the pipe */
	236	status = usb_submit_urb(urb, GFP_ATOMIC);
	237	if (status) {
	238	dev_err(&port->dev,
309a0579	239	"%s - usb_submit_urb(write endpoint) failed status = %d\n",
648d4e16 GKH	240	__func__, status);
	241	count = status;
	242	goto error;
	243	}
	244
	245	/* we are done with this urb, so let the host driver
	246	* really free it when it is finished with it */
	247	usb_free_urb(urb);
	248
	249	return count;
	250	error:
acbf0e52 JH	251	kfree(dr);
acbf0e52 JH	252	error_no_dr:
648d4e16 GKH	253	usb_free_urb(urb);
	254	error_no_urb:
	255	kfree(buffer);
	256	error_no_buffer:
	257	spin_lock_irqsave(&priv->lock, flags);
	258	--priv->outstanding_urbs;
	259	spin_unlock_irqrestore(&priv->lock, flags);
	260	return count;
	261	}
	262
	263	static int opticon_write_room(struct tty_struct *tty)
	264	{
	265	struct usb_serial_port *port = tty->driver_data;
70d25eee	266	struct opticon_private *priv = usb_get_serial_port_data(port);
648d4e16 GKH	267	unsigned long flags;
648d4e16 GKH	268
648d4e16 GKH	269	/*
	270	* We really can take almost anything the user throws at us
	271	* but let's pick a nice big number to tell the tty
	272	* layer that we have lots of free space, unless we don't.
	273	*/
	274	spin_lock_irqsave(&priv->lock, flags);
	275	if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
	276	spin_unlock_irqrestore(&priv->lock, flags);
d44d9ab7	277	dev_dbg(&port->dev, "%s - write limit hit\n", __func__);
648d4e16 GKH	278	return 0;
	279	}
	280	spin_unlock_irqrestore(&priv->lock, flags);
	281
	282	return 2048;
	283	}
	284
60b33c13	285	static int opticon_tiocmget(struct tty_struct *tty)
faac64ad GKH	286	{
faac64ad GKH	287	struct usb_serial_port *port = tty->driver_data;
70d25eee	288	struct opticon_private *priv = usb_get_serial_port_data(port);
faac64ad GKH	289	unsigned long flags;
	290	int result = 0;
	291
faac64ad GKH	292	spin_lock_irqsave(&priv->lock, flags);
faac64ad GKH	293	if (priv->rts)
309a0579 MJ	294	result \|= TIOCM_RTS;
	295	if (priv->cts)
	296	result \|= TIOCM_CTS;
faac64ad GKH	297	spin_unlock_irqrestore(&priv->lock, flags);
faac64ad GKH	298
d44d9ab7	299	dev_dbg(&port->dev, "%s - %x\n", __func__, result);
faac64ad GKH	300	return result;
	301	}
	302
4acfaf82	303	static int opticon_tiocmset(struct tty_struct *tty,
309a0579 MJ	304	unsigned int set, unsigned int clear)
	305	{
	306	struct usb_serial_port *port = tty->driver_data;
70d25eee	307	struct opticon_private *priv = usb_get_serial_port_data(port);
309a0579 MJ	308	unsigned long flags;
	309	bool rts;
	310	bool changed = false;
81d5a672	311	int ret;
309a0579	312
309a0579 MJ	313	/* We only support RTS so we only handle that */
	314	spin_lock_irqsave(&priv->lock, flags);
	315
	316	rts = priv->rts;
	317	if (set & TIOCM_RTS)
	318	priv->rts = true;
	319	if (clear & TIOCM_RTS)
	320	priv->rts = false;
	321	changed = rts ^ priv->rts;
	322	spin_unlock_irqrestore(&priv->lock, flags);
	323
	324	if (!changed)
	325	return 0;
	326
94bcef62 JH	327	ret = send_control_msg(port, CONTROL_RTS, !rts);
	328	if (ret)
	329	return usb_translate_errors(ret);
81d5a672	330
94bcef62	331	return 0;
309a0579 MJ	332	}
309a0579 MJ	333
56be1a17	334	static int get_serial_info(struct usb_serial_port *port,
faac64ad GKH	335	struct serial_struct __user *serial)
	336	{
	337	struct serial_struct tmp;
	338
	339	if (!serial)
	340	return -EFAULT;
	341
	342	memset(&tmp, 0x00, sizeof(tmp));
	343
	344	/* fake emulate a 16550 uart to make userspace code happy */
	345	tmp.type = PORT_16550A;
e5b1e206	346	tmp.line = port->minor;
faac64ad GKH	347	tmp.port = 0;
	348	tmp.irq = 0;
	349	tmp.flags = ASYNC_SKIP_TEST \| ASYNC_AUTO_IRQ;
	350	tmp.xmit_fifo_size = 1024;
	351	tmp.baud_base = 9600;
	352	tmp.close_delay = 5*HZ;
	353	tmp.closing_wait = 30*HZ;
	354
	355	if (copy_to_user(serial, &tmp, sizeof(*serial)))
	356	return -EFAULT;
	357	return 0;
	358	}
	359
00a0d0d6	360	static int opticon_ioctl(struct tty_struct *tty,
faac64ad GKH	361	unsigned int cmd, unsigned long arg)
	362	{
	363	struct usb_serial_port *port = tty->driver_data;
faac64ad	364
faac64ad GKH	365	switch (cmd) {
faac64ad GKH	366	case TIOCGSERIAL:
56be1a17	367	return get_serial_info(port,
faac64ad GKH	368	(struct serial_struct __user *)arg);
	369	}
	370
	371	return -ENOIOCTLCMD;
	372	}
	373
57262b82 GKH	374	static int opticon_startup(struct usb_serial *serial)
57262b82 GKH	375	{
a0a5fd92 JH	376	if (!serial->num_bulk_in) {
	377	dev_err(&serial->dev->dev, "no bulk in endpoint\n");
	378	return -ENODEV;
	379	}
57262b82	380
70d25eee JH	381	return 0;
	382	}
	383
	384	static int opticon_port_probe(struct usb_serial_port *port)
	385	{
70d25eee	386	struct opticon_private *priv;
70d25eee	387
57262b82	388	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
70d25eee	389	if (!priv)
57262b82	390	return -ENOMEM;
70d25eee	391
57262b82	392	spin_lock_init(&priv->lock);
0b8718a2	393
70d25eee	394	usb_set_serial_port_data(port, priv);
57262b82	395
70d25eee	396	return 0;
57262b82 GKH	397	}
57262b82 GKH	398
70d25eee	399	static int opticon_port_remove(struct usb_serial_port *port)
f9c99bb8	400	{
70d25eee	401	struct opticon_private *priv = usb_get_serial_port_data(port);
f9c99bb8	402
57262b82	403	kfree(priv);
70d25eee JH	404
70d25eee JH	405	return 0;
57262b82 GKH	406	}
57262b82 GKH	407
57262b82 GKH	408	static struct usb_serial_driver opticon_device = {
	409	.driver = {
	410	.owner = THIS_MODULE,
	411	.name = "opticon",
	412	},
	413	.id_table = id_table,
57262b82	414	.num_ports = 1,
333396fc	415	.bulk_in_size = 256,
57262b82	416	.attach = opticon_startup,
70d25eee JH	417	.port_probe = opticon_port_probe,
70d25eee JH	418	.port_remove = opticon_port_remove,
57262b82	419	.open = opticon_open,
648d4e16 GKH	420	.write = opticon_write,
648d4e16 GKH	421	.write_room = opticon_write_room,
7a6ee2b0 JH	422	.throttle = usb_serial_generic_throttle,
7a6ee2b0 JH	423	.unthrottle = usb_serial_generic_unthrottle,
faac64ad GKH	424	.ioctl = opticon_ioctl,
faac64ad GKH	425	.tiocmget = opticon_tiocmget,
309a0579	426	.tiocmset = opticon_tiocmset,
7a6ee2b0	427	.process_read_urb = opticon_process_read_urb,
57262b82 GKH	428	};
57262b82 GKH	429
f667ddad AS	430	static struct usb_serial_driver * const serial_drivers[] = {
	431	&opticon_device, NULL
	432	};
	433
68e24113	434	module_usb_serial_driver(serial_drivers, id_table);
57262b82	435
309a0579	436	MODULE_DESCRIPTION(DRIVER_DESC);
57262b82	437	MODULE_LICENSE("GPL");