linux/drivers/usb/serial/kl5kusb105.c

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/*
* KLSI KL5KUSB105 chip RS232 converter driver
*
* Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
*
* 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.
*
* All information about the device was acquired using SniffUSB ans snoopUSB
* on Windows98.
* It was written out of frustration with the PalmConnect USB Serial adapter
* sold by Palm Inc.
* Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
* information that was not already available.
*
* It seems that KLSI bought some silicon-design information from ScanLogic,
* whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
* KLSI has firmware available for their devices; it is probable that the
* firmware differs from that used by KLSI in their products. If you have an
* original KLSI device and can provide some information on it, I would be
* most interested in adding support for it here. If you have any information
* on the protocol used (or find errors in my reverse-engineered stuff), please
* let me know.
*
* The code was only tested with a PalmConnect USB adapter; if you
* are adventurous, try it with any KLSI-based device and let me know how it
* breaks so that I can fix it!
*/
/* TODO:
* check modem line signals
* implement handshaking or decide that we do not support it
*/
/* History:
* 0.3a - implemented pools of write URBs
* 0.3 - alpha version for public testing
* 0.2 - TIOCMGET works, so autopilot(1) can be used!
* 0.1 - can be used to to pilot-xfer -p /dev/ttyUSB0 -l
*
* The driver skeleton is mainly based on mct_u232.c and various other
* pieces of code shamelessly copied from the drivers/usb/serial/ directory.
*/
#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 <asm/uaccess.h>
#include <asm/unaligned.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "kl5kusb105.h"
static int debug;
/*
* Version Information
*/
#define DRIVER_VERSION "v0.3a"
#define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>"
#define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
/*
* Function prototypes
*/
static int klsi_105_startup (struct usb_serial *serial);
static void klsi_105_shutdown (struct usb_serial *serial);
static int klsi_105_open (struct usb_serial_port *port,
struct file *filp);
static void klsi_105_close (struct usb_serial_port *port,
struct file *filp);
static int klsi_105_write (struct usb_serial_port *port,
const unsigned char *buf,
int count);
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 13:55:46 +00:00
static void klsi_105_write_bulk_callback (struct urb *urb);
static int klsi_105_chars_in_buffer (struct usb_serial_port *port);
static int klsi_105_write_room (struct usb_serial_port *port);
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 13:55:46 +00:00
static void klsi_105_read_bulk_callback (struct urb *urb);
static void klsi_105_set_termios (struct usb_serial_port *port,
struct ktermios *old);
static void klsi_105_throttle (struct usb_serial_port *port);
static void klsi_105_unthrottle (struct usb_serial_port *port);
/*
static void klsi_105_break_ctl (struct usb_serial_port *port,
int break_state );
*/
static int klsi_105_tiocmget (struct usb_serial_port *port,
struct file *file);
static int klsi_105_tiocmset (struct usb_serial_port *port,
struct file *file, unsigned int set,
unsigned int clear);
/*
* All of the device info needed for the KLSI converters.
*/
static struct usb_device_id id_table [] = {
{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, id_table);
static struct usb_driver kl5kusb105d_driver = {
.name = "kl5kusb105d",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table,
.no_dynamic_id = 1,
};
static struct usb_serial_driver kl5kusb105d_device = {
.driver = {
.owner = THIS_MODULE,
.name = "kl5kusb105d",
},
.description = "KL5KUSB105D / PalmConnect",
.usb_driver = &kl5kusb105d_driver,
.id_table = id_table,
.num_ports = 1,
.open = klsi_105_open,
.close = klsi_105_close,
.write = klsi_105_write,
.write_bulk_callback = klsi_105_write_bulk_callback,
.chars_in_buffer = klsi_105_chars_in_buffer,
.write_room = klsi_105_write_room,
.read_bulk_callback =klsi_105_read_bulk_callback,
.set_termios = klsi_105_set_termios,
/*.break_ctl = klsi_105_break_ctl,*/
.tiocmget = klsi_105_tiocmget,
.tiocmset = klsi_105_tiocmset,
.attach = klsi_105_startup,
.shutdown = klsi_105_shutdown,
.throttle = klsi_105_throttle,
.unthrottle = klsi_105_unthrottle,
};
struct klsi_105_port_settings {
__u8 pktlen; /* always 5, it seems */
__u8 baudrate;
__u8 databits;
__u8 unknown1;
__u8 unknown2;
} __attribute__ ((packed));
/* we implement a pool of NUM_URBS urbs per usb_serial */
#define NUM_URBS 1
#define URB_TRANSFER_BUFFER_SIZE 64
struct klsi_105_private {
struct klsi_105_port_settings cfg;
struct ktermios termios;
unsigned long line_state; /* modem line settings */
/* write pool */
struct urb * write_urb_pool[NUM_URBS];
spinlock_t lock;
unsigned long bytes_in;
unsigned long bytes_out;
};
/*
* Handle vendor specific USB requests
*/
#define KLSI_TIMEOUT 5000 /* default urb timeout */
static int klsi_105_chg_port_settings(struct usb_serial_port *port,
struct klsi_105_port_settings *settings)
{
int rc;
rc = usb_control_msg(port->serial->dev,
usb_sndctrlpipe(port->serial->dev, 0),
KL5KUSB105A_SIO_SET_DATA,
USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
0, /* value */
0, /* index */
settings,
sizeof(struct klsi_105_port_settings),
KLSI_TIMEOUT);
if (rc < 0)
err("Change port settings failed (error = %d)", rc);
info("%s - %d byte block, baudrate %x, databits %d, u1 %d, u2 %d",
__func__,
settings->pktlen,
settings->baudrate, settings->databits,
settings->unknown1, settings->unknown2);
return rc;
} /* klsi_105_chg_port_settings */
/* translate a 16-bit status value from the device to linux's TIO bits */
static unsigned long klsi_105_status2linestate(const __u16 status)
{
unsigned long res = 0;
res = ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
| ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
;
return res;
}
/*
* Read line control via vendor command and return result through
* *line_state_p
*/
/* It seems that the status buffer has always only 2 bytes length */
#define KLSI_STATUSBUF_LEN 2
static int klsi_105_get_line_state(struct usb_serial_port *port,
unsigned long *line_state_p)
{
int rc;
__u8 status_buf[KLSI_STATUSBUF_LEN] = { -1,-1};
__u16 status;
info("%s - sending SIO Poll request", __func__);
rc = usb_control_msg(port->serial->dev,
usb_rcvctrlpipe(port->serial->dev, 0),
KL5KUSB105A_SIO_POLL,
USB_TYPE_VENDOR | USB_DIR_IN,
0, /* value */
0, /* index */
status_buf, KLSI_STATUSBUF_LEN,
10000
);
if (rc < 0)
err("Reading line status failed (error = %d)", rc);
else {
status = le16_to_cpu(get_unaligned((__le16 *)status_buf));
info("%s - read status %x %x", __func__,
status_buf[0], status_buf[1]);
*line_state_p = klsi_105_status2linestate(status);
}
return rc;
}
/*
* Driver's tty interface functions
*/
static int klsi_105_startup (struct usb_serial *serial)
{
struct klsi_105_private *priv;
int i, j;
/* check if we support the product id (see keyspan.c)
* FIXME
*/
/* allocate the private data structure */
for (i=0; i<serial->num_ports; i++) {
priv = kmalloc(sizeof(struct klsi_105_private),
GFP_KERNEL);
if (!priv) {
dbg("%skmalloc for klsi_105_private failed.", __func__);
i--;
goto err_cleanup;
}
/* set initial values for control structures */
priv->cfg.pktlen = 5;
priv->cfg.baudrate = kl5kusb105a_sio_b9600;
priv->cfg.databits = kl5kusb105a_dtb_8;
priv->cfg.unknown1 = 0;
priv->cfg.unknown2 = 1;
priv->line_state = 0;
priv->bytes_in = 0;
priv->bytes_out = 0;
usb_set_serial_port_data(serial->port[i], priv);
spin_lock_init (&priv->lock);
for (j=0; j<NUM_URBS; j++) {
struct urb* urb = usb_alloc_urb(0, GFP_KERNEL);
priv->write_urb_pool[j] = urb;
if (urb == NULL) {
err("No more urbs???");
goto err_cleanup;
}
urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE,
GFP_KERNEL);
if (!urb->transfer_buffer) {
err("%s - out of memory for urb buffers.", __func__);
goto err_cleanup;
}
}
/* priv->termios is left uninitalized until port opening */
init_waitqueue_head(&serial->port[i]->write_wait);
}
return 0;
err_cleanup:
for (; i >= 0; i--) {
priv = usb_get_serial_port_data(serial->port[i]);
for (j=0; j < NUM_URBS; j++) {
if (priv->write_urb_pool[j]) {
kfree(priv->write_urb_pool[j]->transfer_buffer);
usb_free_urb(priv->write_urb_pool[j]);
}
}
usb_set_serial_port_data(serial->port[i], NULL);
}
return -ENOMEM;
} /* klsi_105_startup */
static void klsi_105_shutdown (struct usb_serial *serial)
{
int i;
dbg("%s", __func__);
/* stop reads and writes on all ports */
for (i=0; i < serial->num_ports; ++i) {
struct klsi_105_private *priv = usb_get_serial_port_data(serial->port[i]);
unsigned long flags;
if (priv) {
/* kill our write urb pool */
int j;
struct urb **write_urbs = priv->write_urb_pool;
spin_lock_irqsave(&priv->lock,flags);
for (j = 0; j < NUM_URBS; j++) {
if (write_urbs[j]) {
/* FIXME - uncomment the following
* usb_kill_urb call when the host
* controllers get fixed to set
* urb->dev = NULL after the urb is
* finished. Otherwise this call
* oopses. */
/* usb_kill_urb(write_urbs[j]); */
kfree(write_urbs[j]->transfer_buffer);
usb_free_urb (write_urbs[j]);
}
}
spin_unlock_irqrestore (&priv->lock, flags);
kfree(priv);
usb_set_serial_port_data(serial->port[i], NULL);
}
}
} /* klsi_105_shutdown */
static int klsi_105_open (struct usb_serial_port *port, struct file *filp)
{
struct klsi_105_private *priv = usb_get_serial_port_data(port);
int retval = 0;
int rc;
int i;
unsigned long line_state;
struct klsi_105_port_settings cfg;
unsigned long flags;
dbg("%s port %d", __func__, port->number);
/* force low_latency on so that our tty_push actually forces
* the data through
* port->tty->low_latency = 1; */
/* Do a defined restart:
* Set up sane default baud rate and send the 'READ_ON'
* vendor command.
* FIXME: set modem line control (how?)
* Then read the modem line control and store values in
* priv->line_state.
*/
cfg.pktlen = 5;
cfg.baudrate = kl5kusb105a_sio_b9600;
cfg.databits = kl5kusb105a_dtb_8;
cfg.unknown1 = 0;
cfg.unknown2 = 1;
klsi_105_chg_port_settings(port, &cfg);
/* set up termios structure */
spin_lock_irqsave (&priv->lock, flags);
priv->termios.c_iflag = port->tty->termios->c_iflag;
priv->termios.c_oflag = port->tty->termios->c_oflag;
priv->termios.c_cflag = port->tty->termios->c_cflag;
priv->termios.c_lflag = port->tty->termios->c_lflag;
for (i=0; i<NCCS; i++)
priv->termios.c_cc[i] = port->tty->termios->c_cc[i];
priv->cfg.pktlen = cfg.pktlen;
priv->cfg.baudrate = cfg.baudrate;
priv->cfg.databits = cfg.databits;
priv->cfg.unknown1 = cfg.unknown1;
priv->cfg.unknown2 = cfg.unknown2;
spin_unlock_irqrestore (&priv->lock, flags);
/* READ_ON and urb submission */
usb_fill_bulk_urb(port->read_urb, port->serial->dev,
usb_rcvbulkpipe(port->serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
klsi_105_read_bulk_callback,
port);
rc = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (rc) {
err("%s - failed submitting read urb, error %d", __func__, rc);
retval = rc;
goto exit;
}
rc = usb_control_msg(port->serial->dev,
usb_sndctrlpipe(port->serial->dev,0),
KL5KUSB105A_SIO_CONFIGURE,
USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
KL5KUSB105A_SIO_CONFIGURE_READ_ON,
0, /* index */
NULL,
0,
KLSI_TIMEOUT);
if (rc < 0) {
err("Enabling read failed (error = %d)", rc);
retval = rc;
} else
dbg("%s - enabled reading", __func__);
rc = klsi_105_get_line_state(port, &line_state);
if (rc >= 0) {
spin_lock_irqsave (&priv->lock, flags);
priv->line_state = line_state;
spin_unlock_irqrestore (&priv->lock, flags);
dbg("%s - read line state 0x%lx", __func__, line_state);
retval = 0;
} else
retval = rc;
exit:
return retval;
} /* klsi_105_open */
static void klsi_105_close (struct usb_serial_port *port, struct file *filp)
{
struct klsi_105_private *priv = usb_get_serial_port_data(port);
int rc;
dbg("%s port %d", __func__, port->number);
mutex_lock(&port->serial->disc_mutex);
if (!port->serial->disconnected) {
/* send READ_OFF */
rc = usb_control_msg (port->serial->dev,
usb_sndctrlpipe(port->serial->dev, 0),
KL5KUSB105A_SIO_CONFIGURE,
USB_TYPE_VENDOR | USB_DIR_OUT,
KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
0, /* index */
NULL, 0,
KLSI_TIMEOUT);
if (rc < 0)
err("Disabling read failed (error = %d)", rc);
}
mutex_unlock(&port->serial->disc_mutex);
/* shutdown our bulk reads and writes */
usb_kill_urb(port->write_urb);
usb_kill_urb(port->read_urb);
/* unlink our write pool */
/* FIXME */
/* wgg - do I need this? I think so. */
usb_kill_urb(port->interrupt_in_urb);
info("kl5kusb105 port stats: %ld bytes in, %ld bytes out", priv->bytes_in, priv->bytes_out);
} /* klsi_105_close */
/* We need to write a complete 64-byte data block and encode the
* number actually sent in the first double-byte, LSB-order. That
* leaves at most 62 bytes of payload.
*/
#define KLSI_105_DATA_OFFSET 2 /* in the bulk urb data block */
static int klsi_105_write (struct usb_serial_port *port,
const unsigned char *buf, int count)
{
struct klsi_105_private *priv = usb_get_serial_port_data(port);
int result, size;
int bytes_sent=0;
dbg("%s - port %d", __func__, port->number);
while (count > 0) {
/* try to find a free urb (write 0 bytes if none) */
struct urb *urb = NULL;
unsigned long flags;
int i;
/* since the pool is per-port we might not need the spin lock !? */
spin_lock_irqsave (&priv->lock, flags);
for (i=0; i<NUM_URBS; i++) {
if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
urb = priv->write_urb_pool[i];
dbg("%s - using pool URB %d", __func__, i);
break;
}
}
spin_unlock_irqrestore (&priv->lock, flags);
if (urb==NULL) {
dbg("%s - no more free urbs", __func__);
goto exit;
}
if (urb->transfer_buffer == NULL) {
urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
if (urb->transfer_buffer == NULL) {
err("%s - no more kernel memory...", __func__);
goto exit;
}
}
size = min (count, port->bulk_out_size - KLSI_105_DATA_OFFSET);
size = min (size, URB_TRANSFER_BUFFER_SIZE - KLSI_105_DATA_OFFSET);
memcpy (urb->transfer_buffer + KLSI_105_DATA_OFFSET, buf, size);
/* write payload size into transfer buffer */
((__u8 *)urb->transfer_buffer)[0] = (__u8) (size & 0xFF);
((__u8 *)urb->transfer_buffer)[1] = (__u8) ((size & 0xFF00)>>8);
/* set up our urb */
usb_fill_bulk_urb(urb, port->serial->dev,
usb_sndbulkpipe(port->serial->dev,
port->bulk_out_endpointAddress),
urb->transfer_buffer,
URB_TRANSFER_BUFFER_SIZE,
klsi_105_write_bulk_callback,
port);
/* send the data out the bulk port */
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result) {
err("%s - failed submitting write urb, error %d", __func__, result);
goto exit;
}
buf += size;
bytes_sent += size;
count -= size;
}
exit:
/* lockless, but it's for debug info only... */
priv->bytes_out+=bytes_sent;
return bytes_sent; /* that's how much we wrote */
} /* klsi_105_write */
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 13:55:46 +00:00
static void klsi_105_write_bulk_callback ( struct urb *urb)
{
struct usb_serial_port *port = urb->context;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
if (status) {
dbg("%s - nonzero write bulk status received: %d", __func__,
status);
return;
}
usb_serial_port_softint(port);
} /* klsi_105_write_bulk_completion_callback */
/* return number of characters currently in the writing process */
static int klsi_105_chars_in_buffer (struct usb_serial_port *port)
{
int chars = 0;
int i;
unsigned long flags;
struct klsi_105_private *priv = usb_get_serial_port_data(port);
spin_lock_irqsave (&priv->lock, flags);
for (i = 0; i < NUM_URBS; ++i) {
if (priv->write_urb_pool[i]->status == -EINPROGRESS) {
chars += URB_TRANSFER_BUFFER_SIZE;
}
}
spin_unlock_irqrestore (&priv->lock, flags);
dbg("%s - returns %d", __func__, chars);
return (chars);
}
static int klsi_105_write_room (struct usb_serial_port *port)
{
unsigned long flags;
int i;
int room = 0;
struct klsi_105_private *priv = usb_get_serial_port_data(port);
spin_lock_irqsave (&priv->lock, flags);
for (i = 0; i < NUM_URBS; ++i) {
if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
room += URB_TRANSFER_BUFFER_SIZE;
}
}
spin_unlock_irqrestore (&priv->lock, flags);
dbg("%s - returns %d", __func__, room);
return (room);
}
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 13:55:46 +00:00
static void klsi_105_read_bulk_callback (struct urb *urb)
{
struct usb_serial_port *port = urb->context;
struct klsi_105_private *priv = usb_get_serial_port_data(port);
struct tty_struct *tty;
unsigned char *data = urb->transfer_buffer;
int rc;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
/* The urb might have been killed. */
if (status) {
dbg("%s - nonzero read bulk status received: %d", __func__,
status);
return;
}
/* The data received is again preceded by a length double-byte in LSB-
* first order (see klsi_105_write() )
*/
if (urb->actual_length == 0) {
/* empty urbs seem to happen, we ignore them */
/* dbg("%s - emtpy URB", __func__); */
;
} else if (urb->actual_length <= 2) {
dbg("%s - size %d URB not understood", __func__,
urb->actual_length);
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
} else {
int bytes_sent = ((__u8 *) data)[0] +
((unsigned int) ((__u8 *) data)[1] << 8);
tty = port->tty;
/* we should immediately resubmit the URB, before attempting
* to pass the data on to the tty layer. But that needs locking
* against re-entry an then mixed-up data because of
* intermixed tty_flip_buffer_push()s
* FIXME
*/
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
if (bytes_sent + 2 > urb->actual_length) {
dbg("%s - trying to read more data than available"
" (%d vs. %d)", __func__,
bytes_sent+2, urb->actual_length);
/* cap at implied limit */
bytes_sent = urb->actual_length - 2;
}
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 04:54:13 +00:00
tty_buffer_request_room(tty, bytes_sent);
tty_insert_flip_string(tty, data + 2, bytes_sent);
tty_flip_buffer_push(tty);
/* again lockless, but debug info only */
priv->bytes_in += bytes_sent;
}
/* Continue trying to always read */
usb_fill_bulk_urb(port->read_urb, port->serial->dev,
usb_rcvbulkpipe(port->serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
klsi_105_read_bulk_callback,
port);
rc = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (rc)
err("%s - failed resubmitting read urb, error %d", __func__, rc);
} /* klsi_105_read_bulk_callback */
static void klsi_105_set_termios (struct usb_serial_port *port,
struct ktermios *old_termios)
{
struct klsi_105_private *priv = usb_get_serial_port_data(port);
struct tty_struct *tty = port->tty;
unsigned int iflag = tty->termios->c_iflag;
unsigned int old_iflag = old_termios->c_iflag;
unsigned int cflag = tty->termios->c_cflag;
unsigned int old_cflag = old_termios->c_cflag;
struct klsi_105_port_settings cfg;
unsigned long flags;
speed_t baud;
/* lock while we are modifying the settings */
spin_lock_irqsave (&priv->lock, flags);
/*
* Update baud rate
*/
baud = tty_get_baud_rate(tty);
if( (cflag & CBAUD) != (old_cflag & CBAUD) ) {
/* reassert DTR and (maybe) RTS on transition from B0 */
if( (old_cflag & CBAUD) == B0 ) {
dbg("%s: baud was B0", __func__);
#if 0
priv->control_state |= TIOCM_DTR;
/* don't set RTS if using hardware flow control */
if (!(old_cflag & CRTSCTS)) {
priv->control_state |= TIOCM_RTS;
}
mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
}
}
switch(baud) {
case 0: /* handled below */
break;
case 1200:
priv->cfg.baudrate = kl5kusb105a_sio_b1200;
break;
case 2400:
priv->cfg.baudrate = kl5kusb105a_sio_b2400;
break;
case 4800:
priv->cfg.baudrate = kl5kusb105a_sio_b4800;
break;
case 9600:
priv->cfg.baudrate = kl5kusb105a_sio_b9600;
break;
case 19200:
priv->cfg.baudrate = kl5kusb105a_sio_b19200;
break;
case 38400:
priv->cfg.baudrate = kl5kusb105a_sio_b38400;
break;
case 57600:
priv->cfg.baudrate = kl5kusb105a_sio_b57600;
break;
case 115200:
priv->cfg.baudrate = kl5kusb105a_sio_b115200;
break;
default:
dbg("KLSI USB->Serial converter:"
" unsupported baudrate request, using default"
" of 9600");
priv->cfg.baudrate = kl5kusb105a_sio_b9600;
baud = 9600;
break;
}
if ((cflag & CBAUD) == B0 ) {
dbg("%s: baud is B0", __func__);
/* Drop RTS and DTR */
/* maybe this should be simulated by sending read
* disable and read enable messages?
*/
;
#if 0
priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
}
tty_encode_baud_rate(tty, baud, baud);
if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
/* set the number of data bits */
switch (cflag & CSIZE) {
case CS5:
dbg("%s - 5 bits/byte not supported", __func__);
spin_unlock_irqrestore (&priv->lock, flags);
return ;
case CS6:
dbg("%s - 6 bits/byte not supported", __func__);
spin_unlock_irqrestore (&priv->lock, flags);
return ;
case CS7:
priv->cfg.databits = kl5kusb105a_dtb_7;
break;
case CS8:
priv->cfg.databits = kl5kusb105a_dtb_8;
break;
default:
err("CSIZE was not CS5-CS8, using default of 8");
priv->cfg.databits = kl5kusb105a_dtb_8;
break;
}
}
/*
* Update line control register (LCR)
*/
if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
|| (cflag & CSTOPB) != (old_cflag & CSTOPB) ) {
/* Not currently supported */
tty->termios->c_cflag &= ~(PARENB|PARODD|CSTOPB);
#if 0
priv->last_lcr = 0;
/* set the parity */
if (cflag & PARENB)
priv->last_lcr |= (cflag & PARODD) ?
MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
else
priv->last_lcr |= MCT_U232_PARITY_NONE;
/* set the number of stop bits */
priv->last_lcr |= (cflag & CSTOPB) ?
MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
mct_u232_set_line_ctrl(serial, priv->last_lcr);
#endif
;
}
/*
* Set flow control: well, I do not really now how to handle DTR/RTS.
* Just do what we have seen with SniffUSB on Win98.
*/
if( (iflag & IXOFF) != (old_iflag & IXOFF)
|| (iflag & IXON) != (old_iflag & IXON)
|| (cflag & CRTSCTS) != (old_cflag & CRTSCTS) ) {
/* Not currently supported */
tty->termios->c_cflag &= ~CRTSCTS;
/* Drop DTR/RTS if no flow control otherwise assert */
#if 0
if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS) )
priv->control_state |= TIOCM_DTR | TIOCM_RTS;
else
priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
;
}
memcpy (&cfg, &priv->cfg, sizeof(cfg));
spin_unlock_irqrestore (&priv->lock, flags);
/* now commit changes to device */
klsi_105_chg_port_settings(port, &cfg);
} /* klsi_105_set_termios */
#if 0
static void mct_u232_break_ctl( struct usb_serial_port *port, int break_state )
{
struct usb_serial *serial = port->serial;
struct mct_u232_private *priv = (struct mct_u232_private *)port->private;
unsigned char lcr = priv->last_lcr;
dbg("%sstate=%d", __func__, break_state);
if (break_state)
lcr |= MCT_U232_SET_BREAK;
mct_u232_set_line_ctrl(serial, lcr);
} /* mct_u232_break_ctl */
#endif
static int klsi_105_tiocmget (struct usb_serial_port *port, struct file *file)
{
struct klsi_105_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
int rc;
unsigned long line_state;
dbg("%s - request, just guessing", __func__);
rc = klsi_105_get_line_state(port, &line_state);
if (rc < 0) {
err("Reading line control failed (error = %d)", rc);
/* better return value? EAGAIN? */
return rc;
}
spin_lock_irqsave (&priv->lock, flags);
priv->line_state = line_state;
spin_unlock_irqrestore (&priv->lock, flags);
dbg("%s - read line state 0x%lx", __func__, line_state);
return (int)line_state;
}
static int klsi_105_tiocmset (struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear)
{
int retval = -EINVAL;
dbg("%s", __func__);
/* if this ever gets implemented, it should be done something like this:
struct usb_serial *serial = port->serial;
struct klsi_105_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
int control;
spin_lock_irqsave (&priv->lock, flags);
if (set & TIOCM_RTS)
priv->control_state |= TIOCM_RTS;
if (set & TIOCM_DTR)
priv->control_state |= TIOCM_DTR;
if (clear & TIOCM_RTS)
priv->control_state &= ~TIOCM_RTS;
if (clear & TIOCM_DTR)
priv->control_state &= ~TIOCM_DTR;
control = priv->control_state;
spin_unlock_irqrestore (&priv->lock, flags);
retval = mct_u232_set_modem_ctrl(serial, control);
*/
return retval;
}
static void klsi_105_throttle (struct usb_serial_port *port)
{
dbg("%s - port %d", __func__, port->number);
usb_kill_urb(port->read_urb);
}
static void klsi_105_unthrottle (struct usb_serial_port *port)
{
int result;
dbg("%s - port %d", __func__, port->number);
port->read_urb->dev = port->serial->dev;
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (result)
err("%s - failed submitting read urb, error %d", __func__,
result);
}
static int __init klsi_105_init (void)
{
int retval;
retval = usb_serial_register(&kl5kusb105d_device);
if (retval)
goto failed_usb_serial_register;
retval = usb_register(&kl5kusb105d_driver);
if (retval)
goto failed_usb_register;
info(DRIVER_DESC " " DRIVER_VERSION);
return 0;
failed_usb_register:
usb_serial_deregister(&kl5kusb105d_device);
failed_usb_serial_register:
return retval;
}
static void __exit klsi_105_exit (void)
{
usb_deregister (&kl5kusb105d_driver);
usb_serial_deregister (&kl5kusb105d_device);
}
module_init (klsi_105_init);
module_exit (klsi_105_exit);
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "enable extensive debugging messages");
/* vim: set sts=8 ts=8 sw=8: */