drivers/usb/serial/console.c - kernel/msm-4.19 - Gitiles

 /*
  * USB Serial Console driver
  *
  * Copyright (C) 2001 - 2002 Greg Kroah-Hartman (greg@kroah.com)
  *
  *	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.
  *
  * Thanks to Randy Dunlap for the original version of this code.
  *
  */

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/console.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>

 static int debug;

 struct usbcons_info {
 	int			magic;
 	int			break_flag;
 	struct usb_serial_port	*port;
 };

 static struct usbcons_info usbcons_info;
 static struct console usbcons;

 /*
  * ------------------------------------------------------------
  * USB Serial console driver
  *
  * Much of the code here is copied from drivers/char/serial.c
  * and implements a phony serial console in the same way that
  * serial.c does so that in case some software queries it,
  * it will get the same results.
  *
  * Things that are different from the way the serial port code
  * does things, is that we call the lower level usb-serial
  * driver code to initialize the device, and we set the initial
  * console speeds based on the command line arguments.
  * ------------------------------------------------------------
  */


 /*
  * The parsing of the command line works exactly like the
  * serial.c code, except that the specifier is "ttyUSB" instead
  * of "ttyS".
  */
 static int usb_console_setup(struct console *co, char *options)
 {
 	struct usbcons_info *info = &usbcons_info;
 	int baud = 9600;
 	int bits = 8;
 	int parity = 'n';
 	int doflow = 0;
 	int cflag = CREAD | HUPCL | CLOCAL;
 	char *s;
 	struct usb_serial *serial;
 	struct usb_serial_port *port;
 	int retval = 0;
 	struct tty_struct *tty;
 	struct ktermios *termios;

 	dbg ("%s", __FUNCTION__);

 	if (options) {
 		baud = simple_strtoul(options, NULL, 10);
 		s = options;
 		while (*s >= '0' && *s <= '9')
 			s++;
 		if (*s)
 			parity = *s++;
 		if (*s)
 			bits   = *s++ - '0';
 		if (*s)
 			doflow = (*s++ == 'r');
 	}

 	/* build a cflag setting */
 	switch (baud) {
 		case 1200:
 			cflag |= B1200;
 			break;
 		case 2400:
 			cflag |= B2400;
 			break;
 		case 4800:
 			cflag |= B4800;
 			break;
 		case 19200:
 			cflag |= B19200;
 			break;
 		case 38400:
 			cflag |= B38400;
 			break;
 		case 57600:
 			cflag |= B57600;
 			break;
 		case 115200:
 			cflag |= B115200;
 			break;
 		case 9600:
 		default:
 			cflag |= B9600;
 			/*
 			 * Set this to a sane value to prevent a divide error
 			 */
 			baud  = 9600;
 			break;
 	}
 	switch (bits) {
 		case 7:
 			cflag |= CS7;
 			break;
 		default:
 		case 8:
 			cflag |= CS8;
 			break;
 	}
 	switch (parity) {
 		case 'o': case 'O':
 			cflag |= PARODD;
 			break;
 		case 'e': case 'E':
 			cflag |= PARENB;
 			break;
 	}
 	co->cflag = cflag;

 	/*
 	 * no need to check the index here: if the index is wrong, console
 	 * code won't call us
 	 */
 	serial = usb_serial_get_by_index(co->index);
 	if (serial == NULL) {
 		/* no device is connected yet, sorry :( */
 		err ("No USB device connected to ttyUSB%i", co->index);
 		return -ENODEV;
 	}

 	port = serial->port[0];
 	port->tty = NULL;

 	info->port = port;

 	++port->open_count;
 	if (port->open_count == 1) {
 		/* only call the device specific open if this
 		 * is the first time the port is opened */
 		if (serial->type->open)
 			retval = serial->type->open(port, NULL);
 		else
 			retval = usb_serial_generic_open(port, NULL);
 		if (retval)
 			port->open_count = 0;
 	}

 	if (retval) {
 		err ("could not open USB console port");
 		return retval;
 	}

 	if (serial->type->set_termios) {
 		struct ktermios dummy;
 		/* build up a fake tty structure so that the open call has something
 		 * to look at to get the cflag value */
 		tty = kzalloc(sizeof(*tty), GFP_KERNEL);
 		if (!tty) {
 			err ("no more memory");
 			return -ENOMEM;
 		}
 		termios = kzalloc(sizeof(*termios), GFP_KERNEL);
 		if (!termios) {
 			err ("no more memory");
 			kfree (tty);
 			return -ENOMEM;
 		}
 		memset(&dummy, 0, sizeof(struct ktermios));
 		termios->c_cflag = cflag;
 		tty->termios = termios;
 		port->tty = tty;

 		/* set up the initial termios settings */
 		serial->type->set_termios(port, &dummy);
 		port->tty = NULL;
 		kfree (termios);
 		kfree (tty);
 	}
 	port->console = 1;

 	return 0;
 }

 static void usb_console_write(struct console *co, const char *buf, unsigned count)
 {
 	static struct usbcons_info *info = &usbcons_info;
 	struct usb_serial_port *port = info->port;
 	struct usb_serial *serial;
 	int retval = -ENODEV;

 	if (!port || port->serial->dev->state == USB_STATE_NOTATTACHED)
 		return;
 	serial = port->serial;

 	if (count == 0)
 		return;

 	dbg("%s - port %d, %d byte(s)", __FUNCTION__, port->number, count);

 	if (!port->open_count) {
 		dbg ("%s - port not opened", __FUNCTION__);
 		return;
 	}

 	while (count) {
 		unsigned int i;
 		unsigned int lf;
 		/* search for LF so we can insert CR if necessary */
 		for (i=0, lf=0 ; i < count ; i++) {
 			if (*(buf + i) == 10) {
 				lf = 1;
 				i++;
 				break;
 			}
 		}
 		/* pass on to the driver specific version of this function if it is available */
 		if (serial->type->write)
 			retval = serial->type->write(port, buf, i);
 		else
 			retval = usb_serial_generic_write(port, buf, i);
 		dbg("%s - return value : %d", __FUNCTION__, retval);
 		if (lf) {
 			/* append CR after LF */
 			unsigned char cr = 13;
 			if (serial->type->write)
 				retval = serial->type->write(port, &cr, 1);
 			else
 				retval = usb_serial_generic_write(port, &cr, 1);
 			dbg("%s - return value : %d", __FUNCTION__, retval);
 		}
 		buf += i;
 		count -= i;
 	}
 }

 static struct console usbcons = {
 	.name =		"ttyUSB",
 	.write =	usb_console_write,
 	.setup =	usb_console_setup,
 	.flags =	CON_PRINTBUFFER,
 	.index =	-1,
 };

 void usb_serial_console_disconnect(struct usb_serial *serial)
 {
 	if (serial && serial->port && serial->port[0] && serial->port[0] == usbcons_info.port) {
 		usb_serial_console_exit();
 		usb_serial_put(serial);
 	}
 }

 void usb_serial_console_init (int serial_debug, int minor)
 {
 	debug = serial_debug;

 	if (minor == 0) {
 		/*
 		 * Call register_console() if this is the first device plugged
 		 * in.  If we call it earlier, then the callback to
 		 * console_setup() will fail, as there is not a device seen by
 		 * the USB subsystem yet.
 		 */
 		/*
 		 * Register console.
 		 * NOTES:
 		 * console_setup() is called (back) immediately (from register_console).
 		 * console_write() is called immediately from register_console iff
 		 * CON_PRINTBUFFER is set in flags.
 		 */
 		dbg ("registering the USB serial console.");
 		register_console(&usbcons);
 	}
 }

 void usb_serial_console_exit (void)
 {
 	if (usbcons_info.port) {
 		unregister_console(&usbcons);
 		if (usbcons_info.port->open_count)
 			usbcons_info.port->open_count--;
 		usbcons_info.port = NULL;
 	}
 }
	/*
	* USB Serial Console driver
	*
	* Copyright (C) 2001 - 2002 Greg Kroah-Hartman (greg@kroah.com)
	*
	* 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.
	*
	* Thanks to Randy Dunlap for the original version of this code.
	*
	*/

	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/tty.h>
	#include <linux/console.h>
	#include <linux/usb.h>
	#include <linux/usb/serial.h>

	static int debug;

	struct usbcons_info {
	int magic;
	int break_flag;
	struct usb_serial_port *port;
	};

	static struct usbcons_info usbcons_info;
	static struct console usbcons;

	/*
	* ------------------------------------------------------------
	* USB Serial console driver
	*
	* Much of the code here is copied from drivers/char/serial.c
	* and implements a phony serial console in the same way that
	* serial.c does so that in case some software queries it,
	* it will get the same results.
	*
	* Things that are different from the way the serial port code
	* does things, is that we call the lower level usb-serial
	* driver code to initialize the device, and we set the initial
	* console speeds based on the command line arguments.
	* ------------------------------------------------------------
	*/


	/*
	* The parsing of the command line works exactly like the
	* serial.c code, except that the specifier is "ttyUSB" instead
	* of "ttyS".
	*/
	static int usb_console_setup(struct console co, char options)
	{
	struct usbcons_info *info = &usbcons_info;
	int baud = 9600;
	int bits = 8;
	int parity = 'n';
	int doflow = 0;
	int cflag = CREAD \| HUPCL \| CLOCAL;
	char *s;
	struct usb_serial *serial;
	struct usb_serial_port *port;
	int retval = 0;
	struct tty_struct *tty;
	struct ktermios *termios;

	dbg ("%s", __FUNCTION__);

	if (options) {
	baud = simple_strtoul(options, NULL, 10);
	s = options;
	while (s >= '0' && s <= '9')
	s++;
	if (*s)
	parity = *s++;
	if (*s)
	bits = *s++ - '0';
	if (*s)
	doflow = (*s++ == 'r');
	}

	/* build a cflag setting */
	switch (baud) {
	case 1200:
	cflag \|= B1200;
	break;
	case 2400:
	cflag \|= B2400;
	break;
	case 4800:
	cflag \|= B4800;
	break;
	case 19200:
	cflag \|= B19200;
	break;
	case 38400:
	cflag \|= B38400;
	break;
	case 57600:
	cflag \|= B57600;
	break;
	case 115200:
	cflag \|= B115200;
	break;
	case 9600:
	default:
	cflag \|= B9600;
	/*
	* Set this to a sane value to prevent a divide error
	*/
	baud = 9600;
	break;
	}
	switch (bits) {
	case 7:
	cflag \|= CS7;
	break;
	default:
	case 8:
	cflag \|= CS8;
	break;
	}
	switch (parity) {
	case 'o': case 'O':
	cflag \|= PARODD;
	break;
	case 'e': case 'E':
	cflag \|= PARENB;
	break;
	}
	co->cflag = cflag;

	/*
	* no need to check the index here: if the index is wrong, console
	* code won't call us
	*/
	serial = usb_serial_get_by_index(co->index);
	if (serial == NULL) {
	/* no device is connected yet, sorry :( */
	err ("No USB device connected to ttyUSB%i", co->index);
	return -ENODEV;
	}

	port = serial->port[0];
	port->tty = NULL;

	info->port = port;

	++port->open_count;
	if (port->open_count == 1) {
	/* only call the device specific open if this
	* is the first time the port is opened */
	if (serial->type->open)
	retval = serial->type->open(port, NULL);
	else
	retval = usb_serial_generic_open(port, NULL);
	if (retval)
	port->open_count = 0;
	}

	if (retval) {
	err ("could not open USB console port");
	return retval;
	}

	if (serial->type->set_termios) {
	struct ktermios dummy;
	/* build up a fake tty structure so that the open call has something
	* to look at to get the cflag value */
	tty = kzalloc(sizeof(*tty), GFP_KERNEL);
	if (!tty) {
	err ("no more memory");
	return -ENOMEM;
	}
	termios = kzalloc(sizeof(*termios), GFP_KERNEL);
	if (!termios) {
	err ("no more memory");
	kfree (tty);
	return -ENOMEM;
	}
	memset(&dummy, 0, sizeof(struct ktermios));
	termios->c_cflag = cflag;
	tty->termios = termios;
	port->tty = tty;

	/* set up the initial termios settings */
	serial->type->set_termios(port, &dummy);
	port->tty = NULL;
	kfree (termios);
	kfree (tty);
	}
	port->console = 1;

	return 0;
	}

	static void usb_console_write(struct console co, const char buf, unsigned count)
	{
	static struct usbcons_info *info = &usbcons_info;
	struct usb_serial_port *port = info->port;
	struct usb_serial *serial;
	int retval = -ENODEV;

	if (!port \|\| port->serial->dev->state == USB_STATE_NOTATTACHED)
	return;
	serial = port->serial;

	if (count == 0)
	return;

	dbg("%s - port %d, %d byte(s)", __FUNCTION__, port->number, count);

	if (!port->open_count) {
	dbg ("%s - port not opened", __FUNCTION__);
	return;
	}

	while (count) {
	unsigned int i;
	unsigned int lf;
	/* search for LF so we can insert CR if necessary */
	for (i=0, lf=0 ; i < count ; i++) {
	if (*(buf + i) == 10) {
	lf = 1;
	i++;
	break;
	}
	}
	/* pass on to the driver specific version of this function if it is available */
	if (serial->type->write)
	retval = serial->type->write(port, buf, i);
	else
	retval = usb_serial_generic_write(port, buf, i);
	dbg("%s - return value : %d", __FUNCTION__, retval);
	if (lf) {
	/* append CR after LF */
	unsigned char cr = 13;
	if (serial->type->write)
	retval = serial->type->write(port, &cr, 1);
	else
	retval = usb_serial_generic_write(port, &cr, 1);
	dbg("%s - return value : %d", __FUNCTION__, retval);
	}
	buf += i;
	count -= i;
	}
	}

	static struct console usbcons = {
	.name = "ttyUSB",
	.write = usb_console_write,
	.setup = usb_console_setup,
	.flags = CON_PRINTBUFFER,
	.index = -1,
	};

	void usb_serial_console_disconnect(struct usb_serial *serial)
	{
	if (serial && serial->port && serial->port[0] && serial->port[0] == usbcons_info.port) {
	usb_serial_console_exit();
	usb_serial_put(serial);
	}
	}

	void usb_serial_console_init (int serial_debug, int minor)
	{
	debug = serial_debug;

	if (minor == 0) {
	/*
	* Call register_console() if this is the first device plugged
	* in. If we call it earlier, then the callback to
	* console_setup() will fail, as there is not a device seen by
	* the USB subsystem yet.
	*/
	/*
	* Register console.
	* NOTES:
	* console_setup() is called (back) immediately (from register_console).
	* console_write() is called immediately from register_console iff
	* CON_PRINTBUFFER is set in flags.
	*/
	dbg ("registering the USB serial console.");
	register_console(&usbcons);
	}
	}

	void usb_serial_console_exit (void)
	{
	if (usbcons_info.port) {
	unregister_console(&usbcons);
	if (usbcons_info.port->open_count)
	usbcons_info.port->open_count--;
	usbcons_info.port = NULL;
	}
	}