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linux/drivers/usb/serial/belkin_sa.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

615 lines
18 KiB
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/*
* Belkin USB Serial Adapter Driver
*
* Copyright (C) 2000 William Greathouse (wgreathouse@smva.com)
* Copyright (C) 2000-2001 Greg Kroah-Hartman (greg@kroah.com)
*
* This program is largely derived from work by the linux-usb group
* and associated source files. Please see the usb/serial files for
* individual credits and copyrights.
*
* 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
*
* TODO:
* -- Add true modem contol line query capability. Currently we track the
* states reported by the interrupt and the states we request.
* -- Add error reporting back to application for UART error conditions.
* Just point me at how to implement this and I'll do it. I've put the
* framework in, but haven't analyzed the "tty_flip" interface yet.
* -- Add support for flush commands
* -- Add everything that is missing :)
*
* 27-Nov-2001 gkh
* compressed all the differnent device entries into 1.
*
* 30-May-2001 gkh
* switched from using spinlock to a semaphore, which fixes lots of problems.
*
* 08-Apr-2001 gb
* - Identify version on module load.
*
* 12-Mar-2001 gkh
* - Added support for the GoHubs GO-COM232 device which is the same as the
* Peracom device.
*
* 06-Nov-2000 gkh
* - Added support for the old Belkin and Peracom devices.
* - Made the port able to be opened multiple times.
* - Added some defaults incase the line settings are things these devices
* can't support.
*
* 18-Oct-2000 William Greathouse
* Released into the wild (linux-usb-devel)
*
* 17-Oct-2000 William Greathouse
* Add code to recognize firmware version and set hardware flow control
* appropriately. Belkin states that firmware prior to 3.05 does not
* operate correctly in hardware handshake mode. I have verified this
* on firmware 2.05 -- for both RTS and DTR input flow control, the control
* line is not reset. The test performed by the Belkin Win* driver is
* to enable hardware flow control for firmware 2.06 or greater and
* for 1.00 or prior. I am only enabling for 2.06 or greater.
*
* 12-Oct-2000 William Greathouse
* First cut at supporting Belkin USB Serial Adapter F5U103
* I did not have a copy of the original work to support this
* adapter, so pardon any stupid mistakes. All of the information
* I am using to write this driver was acquired by using a modified
* UsbSnoop on Windows2000 and from examining the other USB drivers.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "belkin_sa.h"
static int debug;
/*
* Version Information
*/
#define DRIVER_VERSION "v1.2"
#define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
#define DRIVER_DESC "USB Belkin Serial converter driver"
/* function prototypes for a Belkin USB Serial Adapter F5U103 */
static int belkin_sa_startup (struct usb_serial *serial);
static void belkin_sa_shutdown (struct usb_serial *serial);
static int belkin_sa_open (struct usb_serial_port *port, struct file *filp);
static void belkin_sa_close (struct usb_serial_port *port, struct file *filp);
static void belkin_sa_read_int_callback (struct urb *urb);
static void belkin_sa_set_termios (struct usb_serial_port *port, struct termios * old);
static int belkin_sa_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
static void belkin_sa_break_ctl (struct usb_serial_port *port, int break_state );
static int belkin_sa_tiocmget (struct usb_serial_port *port, struct file *file);
static int belkin_sa_tiocmset (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
static struct usb_device_id id_table_combined [] = {
{ USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
{ USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
{ USB_DEVICE(PERACOM_VID, PERACOM_PID) },
{ USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
{ USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
{ USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, id_table_combined);
static struct usb_driver belkin_driver = {
.name = "belkin",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table_combined,
.no_dynamic_id = 1,
};
/* All of the device info needed for the serial converters */
static struct usb_serial_driver belkin_device = {
.driver = {
.owner = THIS_MODULE,
.name = "belkin",
},
.description = "Belkin / Peracom / GoHubs USB Serial Adapter",
.id_table = id_table_combined,
.num_interrupt_in = 1,
.num_bulk_in = 1,
.num_bulk_out = 1,
.num_ports = 1,
.open = belkin_sa_open,
.close = belkin_sa_close,
.read_int_callback = belkin_sa_read_int_callback, /* How we get the status info */
.ioctl = belkin_sa_ioctl,
.set_termios = belkin_sa_set_termios,
.break_ctl = belkin_sa_break_ctl,
.tiocmget = belkin_sa_tiocmget,
.tiocmset = belkin_sa_tiocmset,
.attach = belkin_sa_startup,
.shutdown = belkin_sa_shutdown,
};
struct belkin_sa_private {
spinlock_t lock;
unsigned long control_state;
unsigned char last_lsr;
unsigned char last_msr;
int bad_flow_control;
};
/*
* ***************************************************************************
* Belkin USB Serial Adapter F5U103 specific driver functions
* ***************************************************************************
*/
#define WDR_TIMEOUT 5000 /* default urb timeout */
/* assumes that struct usb_serial *serial is available */
#define BSA_USB_CMD(c,v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
(c), BELKIN_SA_SET_REQUEST_TYPE, \
(v), 0, NULL, 0, WDR_TIMEOUT)
/* do some startup allocations not currently performed by usb_serial_probe() */
static int belkin_sa_startup (struct usb_serial *serial)
{
struct usb_device *dev = serial->dev;
struct belkin_sa_private *priv;
/* allocate the private data structure */
priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
if (!priv)
return (-1); /* error */
/* set initial values for control structures */
spin_lock_init(&priv->lock);
priv->control_state = 0;
priv->last_lsr = 0;
priv->last_msr = 0;
/* see comments at top of file */
priv->bad_flow_control = (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
info("bcdDevice: %04x, bfc: %d", le16_to_cpu(dev->descriptor.bcdDevice), priv->bad_flow_control);
init_waitqueue_head(&serial->port[0]->write_wait);
usb_set_serial_port_data(serial->port[0], priv);
return (0);
}
static void belkin_sa_shutdown (struct usb_serial *serial)
{
struct belkin_sa_private *priv;
int i;
dbg ("%s", __FUNCTION__);
/* stop reads and writes on all ports */
for (i=0; i < serial->num_ports; ++i) {
/* My special items, the standard routines free my urbs */
priv = usb_get_serial_port_data(serial->port[i]);
kfree(priv);
}
}
static int belkin_sa_open (struct usb_serial_port *port, struct file *filp)
{
int retval = 0;
dbg("%s port %d", __FUNCTION__, port->number);
/*Start reading from the device*/
/* TODO: Look at possibility of submitting multiple URBs to device to
* enhance buffering. Win trace shows 16 initial read URBs.
*/
port->read_urb->dev = port->serial->dev;
retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (retval) {
err("usb_submit_urb(read bulk) failed");
goto exit;
}
port->interrupt_in_urb->dev = port->serial->dev;
retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
if (retval) {
usb_kill_urb(port->read_urb);
err(" usb_submit_urb(read int) failed");
}
exit:
return retval;
} /* belkin_sa_open */
static void belkin_sa_close (struct usb_serial_port *port, struct file *filp)
{
dbg("%s port %d", __FUNCTION__, port->number);
/* shutdown our bulk reads and writes */
usb_kill_urb(port->write_urb);
usb_kill_urb(port->read_urb);
usb_kill_urb(port->interrupt_in_urb);
} /* belkin_sa_close */
static void belkin_sa_read_int_callback (struct urb *urb)
{
struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
struct belkin_sa_private *priv;
unsigned char *data = urb->transfer_buffer;
int retval;
unsigned long flags;
switch (urb->status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
return;
default:
dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
goto exit;
}
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
/* Handle known interrupt data */
/* ignore data[0] and data[1] */
priv = usb_get_serial_port_data(port);
spin_lock_irqsave(&priv->lock, flags);
priv->last_msr = data[BELKIN_SA_MSR_INDEX];
/* Record Control Line states */
if (priv->last_msr & BELKIN_SA_MSR_DSR)
priv->control_state |= TIOCM_DSR;
else
priv->control_state &= ~TIOCM_DSR;
if (priv->last_msr & BELKIN_SA_MSR_CTS)
priv->control_state |= TIOCM_CTS;
else
priv->control_state &= ~TIOCM_CTS;
if (priv->last_msr & BELKIN_SA_MSR_RI)
priv->control_state |= TIOCM_RI;
else
priv->control_state &= ~TIOCM_RI;
if (priv->last_msr & BELKIN_SA_MSR_CD)
priv->control_state |= TIOCM_CD;
else
priv->control_state &= ~TIOCM_CD;
/* Now to report any errors */
priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
#if 0
/*
* fill in the flip buffer here, but I do not know the relation
* to the current/next receive buffer or characters. I need
* to look in to this before committing any code.
*/
if (priv->last_lsr & BELKIN_SA_LSR_ERR) {
tty = port->tty;
/* Overrun Error */
if (priv->last_lsr & BELKIN_SA_LSR_OE) {
}
/* Parity Error */
if (priv->last_lsr & BELKIN_SA_LSR_PE) {
}
/* Framing Error */
if (priv->last_lsr & BELKIN_SA_LSR_FE) {
}
/* Break Indicator */
if (priv->last_lsr & BELKIN_SA_LSR_BI) {
}
}
#endif
spin_unlock_irqrestore(&priv->lock, flags);
exit:
retval = usb_submit_urb (urb, GFP_ATOMIC);
if (retval)
err ("%s - usb_submit_urb failed with result %d",
__FUNCTION__, retval);
}
static void belkin_sa_set_termios (struct usb_serial_port *port, struct termios *old_termios)
{
struct usb_serial *serial = port->serial;
struct belkin_sa_private *priv = usb_get_serial_port_data(port);
unsigned int iflag;
unsigned int cflag;
unsigned int old_iflag = 0;
unsigned int old_cflag = 0;
__u16 urb_value = 0; /* Will hold the new flags */
unsigned long flags;
unsigned long control_state;
int bad_flow_control;
if ((!port->tty) || (!port->tty->termios)) {
dbg ("%s - no tty or termios structure", __FUNCTION__);
return;
}
iflag = port->tty->termios->c_iflag;
cflag = port->tty->termios->c_cflag;
/* get a local copy of the current port settings */
spin_lock_irqsave(&priv->lock, flags);
control_state = priv->control_state;
bad_flow_control = priv->bad_flow_control;
spin_unlock_irqrestore(&priv->lock, flags);
/* check that they really want us to change something */
if (old_termios) {
if ((cflag == old_termios->c_cflag) &&
(RELEVANT_IFLAG(port->tty->termios->c_iflag) == RELEVANT_IFLAG(old_termios->c_iflag))) {
dbg("%s - nothing to change...", __FUNCTION__);
return;
}
old_iflag = old_termios->c_iflag;
old_cflag = old_termios->c_cflag;
}
/* Set the baud rate */
if( (cflag&CBAUD) != (old_cflag&CBAUD) ) {
/* reassert DTR and (maybe) RTS on transition from B0 */
if( (old_cflag&CBAUD) == B0 ) {
control_state |= (TIOCM_DTR|TIOCM_RTS);
if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
err("Set DTR error");
/* don't set RTS if using hardware flow control */
if (!(old_cflag&CRTSCTS) )
if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 1) < 0)
err("Set RTS error");
}
switch(cflag & CBAUD) {
case B0: /* handled below */ break;
case B300: urb_value = BELKIN_SA_BAUD(300); break;
case B600: urb_value = BELKIN_SA_BAUD(600); break;
case B1200: urb_value = BELKIN_SA_BAUD(1200); break;
case B2400: urb_value = BELKIN_SA_BAUD(2400); break;
case B4800: urb_value = BELKIN_SA_BAUD(4800); break;
case B9600: urb_value = BELKIN_SA_BAUD(9600); break;
case B19200: urb_value = BELKIN_SA_BAUD(19200); break;
case B38400: urb_value = BELKIN_SA_BAUD(38400); break;
case B57600: urb_value = BELKIN_SA_BAUD(57600); break;
case B115200: urb_value = BELKIN_SA_BAUD(115200); break;
case B230400: urb_value = BELKIN_SA_BAUD(230400); break;
default: err("BELKIN USB Serial Adapter: unsupported baudrate request, using default of 9600");
urb_value = BELKIN_SA_BAUD(9600); break;
}
if ((cflag & CBAUD) != B0 ) {
if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
err("Set baudrate error");
} else {
/* Disable flow control */
if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, BELKIN_SA_FLOW_NONE) < 0)
err("Disable flowcontrol error");
/* Drop RTS and DTR */
control_state &= ~(TIOCM_DTR | TIOCM_RTS);
if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
err("DTR LOW error");
if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
err("RTS LOW error");
}
}
/* set the parity */
if( (cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD)) ) {
if (cflag & PARENB)
urb_value = (cflag & PARODD) ? BELKIN_SA_PARITY_ODD : BELKIN_SA_PARITY_EVEN;
else
urb_value = BELKIN_SA_PARITY_NONE;
if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
err("Set parity error");
}
/* set the number of data bits */
if( (cflag&CSIZE) != (old_cflag&CSIZE) ) {
switch (cflag & CSIZE) {
case CS5: urb_value = BELKIN_SA_DATA_BITS(5); break;
case CS6: urb_value = BELKIN_SA_DATA_BITS(6); break;
case CS7: urb_value = BELKIN_SA_DATA_BITS(7); break;
case CS8: urb_value = BELKIN_SA_DATA_BITS(8); break;
default: err("CSIZE was not CS5-CS8, using default of 8");
urb_value = BELKIN_SA_DATA_BITS(8);
break;
}
if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
err("Set data bits error");
}
/* set the number of stop bits */
if( (cflag&CSTOPB) != (old_cflag&CSTOPB) ) {
urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2) : BELKIN_SA_STOP_BITS(1);
if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST, urb_value) < 0)
err("Set stop bits error");
}
/* Set flow control */
if( (iflag&IXOFF) != (old_iflag&IXOFF)
|| (iflag&IXON) != (old_iflag&IXON)
|| (cflag&CRTSCTS) != (old_cflag&CRTSCTS) ) {
urb_value = 0;
if ((iflag & IXOFF) || (iflag & IXON))
urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
else
urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
if (cflag & CRTSCTS)
urb_value |= (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
else
urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
if (bad_flow_control)
urb_value &= ~(BELKIN_SA_FLOW_IRTS);
if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
err("Set flow control error");
}
/* save off the modified port settings */
spin_lock_irqsave(&priv->lock, flags);
priv->control_state = control_state;
spin_unlock_irqrestore(&priv->lock, flags);
} /* belkin_sa_set_termios */
static void belkin_sa_break_ctl( struct usb_serial_port *port, int break_state )
{
struct usb_serial *serial = port->serial;
if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
err("Set break_ctl %d", break_state);
}
static int belkin_sa_tiocmget (struct usb_serial_port *port, struct file *file)
{
struct belkin_sa_private *priv = usb_get_serial_port_data(port);
unsigned long control_state;
unsigned long flags;
dbg("%s", __FUNCTION__);
spin_lock_irqsave(&priv->lock, flags);
control_state = priv->control_state;
spin_unlock_irqrestore(&priv->lock, flags);
return control_state;
}
static int belkin_sa_tiocmset (struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear)
{
struct usb_serial *serial = port->serial;
struct belkin_sa_private *priv = usb_get_serial_port_data(port);
unsigned long control_state;
unsigned long flags;
int retval;
int rts = 0;
int dtr = 0;
dbg("%s", __FUNCTION__);
spin_lock_irqsave(&priv->lock, flags);
control_state = priv->control_state;
if (set & TIOCM_RTS) {
control_state |= TIOCM_RTS;
rts = 1;
}
if (set & TIOCM_DTR) {
control_state |= TIOCM_DTR;
dtr = 1;
}
if (clear & TIOCM_RTS) {
control_state &= ~TIOCM_RTS;
rts = 0;
}
if (clear & TIOCM_DTR) {
control_state &= ~TIOCM_DTR;
dtr = 0;
}
priv->control_state = control_state;
spin_unlock_irqrestore(&priv->lock, flags);
retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
if (retval < 0) {
err("Set RTS error %d", retval);
goto exit;
}
retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
if (retval < 0) {
err("Set DTR error %d", retval);
goto exit;
}
exit:
return retval;
}
static int belkin_sa_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case TIOCMIWAIT:
/* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
/* TODO */
return( 0 );
case TIOCGICOUNT:
/* return count of modemline transitions */
/* TODO */
return 0;
default:
dbg("belkin_sa_ioctl arg not supported - 0x%04x",cmd);
return(-ENOIOCTLCMD);
break;
}
return 0;
} /* belkin_sa_ioctl */
static int __init belkin_sa_init (void)
{
int retval;
retval = usb_serial_register(&belkin_device);
if (retval)
goto failed_usb_serial_register;
retval = usb_register(&belkin_driver);
if (retval)
goto failed_usb_register;
info(DRIVER_DESC " " DRIVER_VERSION);
return 0;
failed_usb_register:
usb_serial_deregister(&belkin_device);
failed_usb_serial_register:
return retval;
}
static void __exit belkin_sa_exit (void)
{
usb_deregister (&belkin_driver);
usb_serial_deregister (&belkin_device);
}
module_init (belkin_sa_init);
module_exit (belkin_sa_exit);
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_VERSION( DRIVER_VERSION );
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
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