keyspan_pda.c

基于S3CEB2410平台LINUX操作系统下 USB驱动源代码

/*
 * USB Keyspan PDA / Xircom / Entregra Converter driver
 *
 * Copyright (c) 1999 - 2001 Greg Kroah-Hartman	<[e-mail]>
 * Copyright (c) 1999, 2000 Brian Warner	<[e-mail]>
 * Copyright (c) 2000 Al Borchers		<[e-mail]>
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 * See Documentation/usb/usb-serial.txt for more information on using this driver
 * 
 * (09/07/2001) gkh
 *	cleaned up the Xircom support.  Added ids for Entregra device which is
 *	the same as the Xircom device.  Enabled the code to be compiled for
 *	either Xircom or Keyspan devices.
 *
 * (08/11/2001) Cristian M. Craciunescu
 *	support for Xircom PGSDB9
 *
 * (05/31/2001) gkh
 *	switched from using spinlock to a semaphore, which fixes lots of problems.
 *
 * (04/08/2001) gb
 *	Identify version on module load.
 * 
 * (11/01/2000) Adam J. Richter
 *	usb_device_id table support
 * 
 * (10/05/2000) gkh
 *	Fixed bug with urb->dev not being set properly, now that the usb
 *	core needs it.
 * 
 * (08/28/2000) gkh
 *	Added locks for SMP safeness.
 *	Fixed MOD_INC and MOD_DEC logic and the ability to open a port more 
 *	than once.
 * 
 * (07/20/2000) borchers
 *	- keyspan_pda_write no longer sleeps if it is called on interrupt time;
 *	  PPP and the line discipline with stty echo on can call write on
 *	  interrupt time and this would cause an oops if write slept
 *	- if keyspan_pda_write is in an interrupt, it will not call
 *	  usb_control_msg (which sleeps) to query the room in the device
 *	  buffer, it simply uses the current room value it has
 *	- if the urb is busy or if it is throttled keyspan_pda_write just
 *	  returns 0, rather than sleeping to wait for this to change; the
 *	  write_chan code in n_tty.c will sleep if needed before calling
 *	  keyspan_pda_write again
 *	- if the device needs to be unthrottled, write now queues up the
 *	  call to usb_control_msg (which sleeps) to unthrottle the device
 *	- the wakeups from keyspan_pda_write_bulk_callback are queued rather
 *	  than done directly from the callback to avoid the race in write_chan
 *	- keyspan_pda_chars_in_buffer also indicates its buffer is full if the
 *	  urb status is -EINPROGRESS, meaning it cannot write at the moment
 *      
 * (07/19/2000) gkh
 *	Added module_init and module_exit functions to handle the fact that this
 *	driver is a loadable module now.
 *
 * (03/26/2000) gkh
 *	Split driver up into device specific pieces.
 * 
 */


#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/fcntl.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/tqueue.h>
#include <linux/usb.h>

#ifdef CONFIG_USB_SERIAL_DEBUG
	static int debug = 1;
#else
	static int debug;
#endif


struct ezusb_hex_record {
	__u16 address;
	__u8 data_size;
	__u8 data[16];
};

/* make a simple define to handle if we are compiling keyspan_pda or xircom support */
#if defined(CONFIG_USB_SERIAL_KEYSPAN_PDA) || defined(CONFIG_USB_SERIAL_KEYSPAN_PDA_MODULE)
	#define KEYSPAN
#else
	#undef KEYSPAN
#endif
#if defined(CONFIG_USB_SERIAL_XIRCOM) || defined(CONFIG_USB_SERIAL_XIRCOM_MODULE)
	#define XIRCOM
#else
	#undef XIRCOM
#endif

#ifdef KEYSPAN
#include "keyspan_pda_fw.h"
#endif

#ifdef XIRCOM
#include "xircom_pgs_fw.h"
#endif

#include "usb-serial.h"

/*
 * Version Information
 */
#define DRIVER_VERSION "v1.1"
#define DRIVER_AUTHOR "Brian Warner <[e-mail]>"
#define DRIVER_DESC "USB Keyspan PDA Converter driver"

struct keyspan_pda_private {
	int			tx_room;
	int			tx_throttled;
	struct tq_struct	wakeup_task;
	struct tq_struct	unthrottle_task;
};


#define KEYSPAN_VENDOR_ID		0x06cd
#define KEYSPAN_PDA_FAKE_ID		0x0103
#define KEYSPAN_PDA_ID			0x0104 /* no clue */

/* For Xircom PGSDB9 and older Entregra version of the same device */
#define XIRCOM_VENDOR_ID		0x085a
#define XIRCOM_FAKE_ID			0x8027
#define ENTREGRA_VENDOR_ID		0x1645
#define ENTREGRA_FAKE_ID		0x8093

static __devinitdata struct usb_device_id id_table_combined [] = {
#ifdef KEYSPAN
	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
#endif
#ifdef XIRCOM
	{ USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
	{ USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
#endif
	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
	{ }						/* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, id_table_combined);

static __devinitdata struct usb_device_id id_table_std [] = {
	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
	{ }						/* Terminating entry */
};

#ifdef KEYSPAN
static __devinitdata struct usb_device_id id_table_fake [] = {
	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
	{ }						/* Terminating entry */
};
#endif

#ifdef XIRCOM
static __devinitdata struct usb_device_id id_table_fake_xircom [] = {
        { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
        { }                                             
};

static __devinitdata struct usb_device_id id_table_fake_entregra [] = {
        { USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
        { }                                             
};
#endif

static void keyspan_pda_wakeup_write( struct usb_serial_port *port )
{

	struct tty_struct *tty = port->tty;

	/* wake up port processes */
	wake_up_interruptible( &port->write_wait );

	/* wake up line discipline */
	if( (tty->flags & (1 << TTY_DO_WRITE_WAKEUP))
	&& tty->ldisc.write_wakeup )
		(tty->ldisc.write_wakeup)(tty);

	/* wake up other tty processes */
	wake_up_interruptible( &tty->write_wait );
	/* For 2.2.16 backport -- wake_up_interruptible( &tty->poll_wait ); */
	MOD_DEC_USE_COUNT;
}

static void keyspan_pda_request_unthrottle( struct usb_serial *serial )
{

	dbg(" request_unthrottle");
	/* ask the device to tell us when the tx buffer becomes
	   sufficiently empty */
	usb_control_msg(serial->dev, 
			     usb_sndctrlpipe(serial->dev, 0),
			     7, /* request_unthrottle */
			     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
			     | USB_DIR_OUT,
			     16, /* value: threshold */
			     0, /* index */
			     NULL,
			     0,
			     2*HZ);
	MOD_DEC_USE_COUNT;
}


static void keyspan_pda_rx_interrupt (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct usb_serial *serial;
       	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	int i;
	struct keyspan_pda_private *priv;
	priv = (struct keyspan_pda_private *)(port->private);

	/* the urb might have been killed. */
	if (urb->status)
		return;
	
	if (port_paranoia_check (port, "keyspan_pda_rx_interrupt")) {
		return;
	}

	serial = port->serial;
	if (serial_paranoia_check (serial, "keyspan_pda_rx_interrupt")) {
		return;
	}
	
 	/* see if the message is data or a status interrupt */
	switch (data[0]) {
	case 0:
		/* rest of message is rx data */
		if (urb->actual_length) {
			tty = serial->port[0].tty;
			for (i = 1; i < urb->actual_length ; ++i) {
				tty_insert_flip_char(tty, data[i], 0);
			}
			tty_flip_buffer_push(tty);
		}
		break;
	case 1:
		/* status interrupt */
		dbg(" rx int, d1=%d, d2=%d", data[1], data[2]);
		switch (data[1]) {
		case 1: /* modemline change */
			break;
		case 2: /* tx unthrottle interrupt */
			tty = serial->port[0].tty;
			priv->tx_throttled = 0;
			/* queue up a wakeup at scheduler time */
			MOD_INC_USE_COUNT;
			if (schedule_task(&priv->wakeup_task) == 0)
				MOD_DEC_USE_COUNT;
			break;
		default:
			break;
		}
		break;
	default:
		break;
	}

	/* INT urbs are automatically re-submitted */
}


static void keyspan_pda_rx_throttle (struct usb_serial_port *port)
{
	/* stop receiving characters. We just turn off the URB request, and
	   let chars pile up in the device. If we're doing hardware
	   flowcontrol, the device will signal the other end when its buffer
	   fills up. If we're doing XON/XOFF, this would be a good time to
	   send an XOFF, although it might make sense to foist that off
	   upon the device too. */

	dbg("keyspan_pda_rx_throttle port %d", port->number);
	usb_unlink_urb(port->interrupt_in_urb);
}


static void keyspan_pda_rx_unthrottle (struct usb_serial_port *port)
{
	/* just restart the receive interrupt URB */
	dbg("keyspan_pda_rx_unthrottle port %d", port->number);
	port->interrupt_in_urb->dev = port->serial->dev;
	if (usb_submit_urb(port->interrupt_in_urb))
		dbg(" usb_submit_urb(read urb) failed");
	return;
}


static int keyspan_pda_setbaud (struct usb_serial *serial, int baud)
{
	int rc;
	int bindex;

	switch(baud) {
		case 110: bindex = 0; break;
		case 300: bindex = 1; break;
		case 1200: bindex = 2; break;
		case 2400: bindex = 3; break;
		case 4800: bindex = 4; break;
		case 9600: bindex = 5; break;
		case 19200: bindex = 6; break;
		case 38400: bindex = 7; break;
		case 57600: bindex = 8; break;
		case 115200: bindex = 9; break;
		default: return -EINVAL;
	}

	/* rather than figure out how to sleep while waiting for this
	   to complete, I just use the "legacy" API. */
	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
			     0, /* set baud */
			     USB_TYPE_VENDOR 
			     | USB_RECIP_INTERFACE
			     | USB_DIR_OUT, /* type */
			     bindex, /* value */
			     0, /* index */
			     NULL, /* &data */
			     0, /* size */
			     2*HZ); /* timeout */
	return(rc);
}


static void keyspan_pda_break_ctl (struct usb_serial_port *port, int break_state)
{
	struct usb_serial *serial = port->serial;
	int value;
	if (break_state == -1)
		value = 1; /* start break */
	else
		value = 0; /* clear break */
	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
			4, /* set break */
			USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
			value, 0, NULL, 0, 2*HZ);
	/* there is something funky about this.. the TCSBRK that 'cu' performs
	   ought to translate into a break_ctl(-1),break_ctl(0) pair HZ/4
	   seconds apart, but it feels like the break sent isn't as long as it
	   is on /dev/ttyS0 */
}


static void keyspan_pda_set_termios (struct usb_serial_port *port, 
				     struct termios *old_termios)
{
	struct usb_serial *serial = port->serial;
	unsigned int cflag = port->tty->termios->c_cflag;

	/* cflag specifies lots of stuff: number of stop bits, parity, number
	   of data bits, baud. What can the device actually handle?:
	   CSTOPB (1 stop bit or 2)
	   PARENB (parity)
	   CSIZE (5bit .. 8bit)
	   There is minimal hw support for parity (a PSW bit seems to hold the
	   parity of whatever is in the accumulator). The UART either deals
	   with 10 bits (start, 8 data, stop) or 11 bits (start, 8 data,
	   1 special, stop). So, with firmware changes, we could do:
	   8N1: 10 bit
	   8N2: 11 bit, extra bit always (mark?)
	   8[EOMS]1: 11 bit, extra bit is parity
	   7[EOMS]1: 10 bit, b0/b7 is parity
	   7[EOMS]2: 11 bit, b0/b7 is parity, extra bit always (mark?)

	   HW flow control is dictated by the tty->termios->c_cflags & CRTSCTS
	   bit.

	   For now, just do baud. */

	switch (cflag & CBAUD) {
		/* we could support more values here, just need to calculate
		   the necessary divisors in the firmware. <asm/termbits.h>
		   has the Bnnn constants. */
		case B110: keyspan_pda_setbaud(serial, 110); break;
		case B300: keyspan_pda_setbaud(serial, 300); break;
		case B1200: keyspan_pda_setbaud(serial, 1200); break;
		case B2400: keyspan_pda_setbaud(serial, 2400); break;
		case B4800: keyspan_pda_setbaud(serial, 4800); break;
		case B9600: keyspan_pda_setbaud(serial, 9600); break;
		case B19200: keyspan_pda_setbaud(serial, 19200); break;
		case B38400: keyspan_pda_setbaud(serial, 38400); break;
		case B57600: keyspan_pda_setbaud(serial, 57600); break;
		case B115200: keyspan_pda_setbaud(serial, 115200); break;
		default: dbg("can't handle requested baud rate"); break;
	}
}


/* modem control pins: DTR and RTS are outputs and can be controlled.
   DCD, RI, DSR, CTS are inputs and can be read. All outputs can also be
   read. The byte passed is: DTR(b7) DCD RI DSR CTS RTS(b2) unused unused */

static int keyspan_pda_get_modem_info(struct usb_serial *serial,
				      unsigned char *value)
{
	int rc;
	unsigned char data;
	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
			     3, /* get pins */
			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_IN,
			     0, 0, &data, 1, 2*HZ);
	if (rc > 0)
		*value = data;
	return rc;
}


static int keyspan_pda_set_modem_info(struct usb_serial *serial,
				      unsigned char value)
{
	int rc;
	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
			     3, /* set pins */
			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_OUT,
			     value, 0, NULL, 0, 2*HZ);
	return rc;
}


static int keyspan_pda_ioctl(struct usb_serial_port *port, struct file *file,
			     unsigned int cmd, unsigned long arg)
{
	struct usb_serial *serial = port->serial;
	int rc;
	unsigned int value;
	unsigned char status, mask;

	switch (cmd) {
	case TIOCMGET: /* get modem pins state */
		rc = keyspan_pda_get_modem_info(serial, &status);
		if (rc < 0)
			return rc;
		value =
			((status & (1<<7)) ? TIOCM_DTR : 0) |
			((status & (1<<6)) ? TIOCM_CAR : 0) |
			((status & (1<<5)) ? TIOCM_RNG : 0) |
			((status & (1<<4)) ? TIOCM_DSR : 0) |
			((status & (1<<3)) ? TIOCM_CTS : 0) |
			((status & (1<<2)) ? TIOCM_RTS : 0);
		if (copy_to_user((unsigned int *)arg, &value, sizeof(int)))
			return -EFAULT;
		return 0;
	case TIOCMSET: /* set a state as returned by MGET */
		if (copy_from_user(&value, (unsigned int *)arg, sizeof(int)))
			return -EFAULT;
		status =
			((value & TIOCM_DTR) ? (1<<7) : 0) |
			((value & TIOCM_CAR) ? (1<<6) : 0) |
			((value & TIOCM_RNG) ? (1<<5) : 0) |
			((value & TIOCM_DSR) ? (1<<4) : 0) |
			((value & TIOCM_CTS) ? (1<<3) : 0) |
			((value & TIOCM_RTS) ? (1<<2) : 0);
		rc = keyspan_pda_set_modem_info(serial, status);
		if (rc < 0)
			return rc;
		return 0;