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android_kernel_samsung_msm8976/drivers/usb/class/cdc-acm.c
Alan Cox 33f0f88f1c [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 08:01:59 -08:00

1166 lines
30 KiB
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/*
* cdc-acm.c
*
* Copyright (c) 1999 Armin Fuerst <fuerst@in.tum.de>
* Copyright (c) 1999 Pavel Machek <pavel@suse.cz>
* Copyright (c) 1999 Johannes Erdfelt <johannes@erdfelt.com>
* Copyright (c) 2000 Vojtech Pavlik <vojtech@suse.cz>
* Copyright (c) 2004 Oliver Neukum <oliver@neukum.name>
* Copyright (c) 2005 David Kubicek <dave@awk.cz>
*
* USB Abstract Control Model driver for USB modems and ISDN adapters
*
* Sponsored by SuSE
*
* ChangeLog:
* v0.9 - thorough cleaning, URBification, almost a rewrite
* v0.10 - some more cleanups
* v0.11 - fixed flow control, read error doesn't stop reads
* v0.12 - added TIOCM ioctls, added break handling, made struct acm kmalloced
* v0.13 - added termios, added hangup
* v0.14 - sized down struct acm
* v0.15 - fixed flow control again - characters could be lost
* v0.16 - added code for modems with swapped data and control interfaces
* v0.17 - added new style probing
* v0.18 - fixed new style probing for devices with more configurations
* v0.19 - fixed CLOCAL handling (thanks to Richard Shih-Ping Chan)
* v0.20 - switched to probing on interface (rather than device) class
* v0.21 - revert to probing on device for devices with multiple configs
* v0.22 - probe only the control interface. if usbcore doesn't choose the
* config we want, sysadmin changes bConfigurationValue in sysfs.
* v0.23 - use softirq for rx processing, as needed by tty layer
* v0.24 - change probe method to evaluate CDC union descriptor
* v0.25 - downstream tasks paralelized to maximize throughput
*/
/*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#undef DEBUG
#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/smp_lock.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/usb_cdc.h>
#include <asm/byteorder.h>
#include <asm/unaligned.h>
#include <linux/list.h>
#include "cdc-acm.h"
/*
* Version Information
*/
#define DRIVER_VERSION "v0.25"
#define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek"
#define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
static struct usb_driver acm_driver;
static struct tty_driver *acm_tty_driver;
static struct acm *acm_table[ACM_TTY_MINORS];
static DECLARE_MUTEX(open_sem);
#define ACM_READY(acm) (acm && acm->dev && acm->used)
/*
* Functions for ACM control messages.
*/
static int acm_ctrl_msg(struct acm *acm, int request, int value, void *buf, int len)
{
int retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
request, USB_RT_ACM, value,
acm->control->altsetting[0].desc.bInterfaceNumber,
buf, len, 5000);
dbg("acm_control_msg: rq: 0x%02x val: %#x len: %#x result: %d", request, value, len, retval);
return retval < 0 ? retval : 0;
}
/* devices aren't required to support these requests.
* the cdc acm descriptor tells whether they do...
*/
#define acm_set_control(acm, control) \
acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, control, NULL, 0)
#define acm_set_line(acm, line) \
acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
#define acm_send_break(acm, ms) \
acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
/*
* Write buffer management.
* All of these assume proper locks taken by the caller.
*/
static int acm_wb_alloc(struct acm *acm)
{
int i, wbn;
struct acm_wb *wb;
wbn = acm->write_current;
i = 0;
for (;;) {
wb = &acm->wb[wbn];
if (!wb->use) {
wb->use = 1;
return wbn;
}
wbn = (wbn + 1) % ACM_NWB;
if (++i >= ACM_NWB)
return -1;
}
}
static void acm_wb_free(struct acm *acm, int wbn)
{
acm->wb[wbn].use = 0;
}
static int acm_wb_is_avail(struct acm *acm)
{
int i, n;
n = 0;
for (i = 0; i < ACM_NWB; i++) {
if (!acm->wb[i].use)
n++;
}
return n;
}
static inline int acm_wb_is_used(struct acm *acm, int wbn)
{
return acm->wb[wbn].use;
}
/*
* Finish write.
*/
static void acm_write_done(struct acm *acm)
{
unsigned long flags;
int wbn;
spin_lock_irqsave(&acm->write_lock, flags);
acm->write_ready = 1;
wbn = acm->write_current;
acm_wb_free(acm, wbn);
acm->write_current = (wbn + 1) % ACM_NWB;
spin_unlock_irqrestore(&acm->write_lock, flags);
}
/*
* Poke write.
*/
static int acm_write_start(struct acm *acm)
{
unsigned long flags;
int wbn;
struct acm_wb *wb;
int rc;
spin_lock_irqsave(&acm->write_lock, flags);
if (!acm->dev) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return -ENODEV;
}
if (!acm->write_ready) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return 0; /* A white lie */
}
wbn = acm->write_current;
if (!acm_wb_is_used(acm, wbn)) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return 0;
}
wb = &acm->wb[wbn];
acm->write_ready = 0;
spin_unlock_irqrestore(&acm->write_lock, flags);
acm->writeurb->transfer_buffer = wb->buf;
acm->writeurb->transfer_dma = wb->dmah;
acm->writeurb->transfer_buffer_length = wb->len;
acm->writeurb->dev = acm->dev;
if ((rc = usb_submit_urb(acm->writeurb, GFP_ATOMIC)) < 0) {
dbg("usb_submit_urb(write bulk) failed: %d", rc);
acm_write_done(acm);
}
return rc;
}
/*
* Interrupt handlers for various ACM device responses
*/
/* control interface reports status changes with "interrupt" transfers */
static void acm_ctrl_irq(struct urb *urb, struct pt_regs *regs)
{
struct acm *acm = urb->context;
struct usb_cdc_notification *dr = urb->transfer_buffer;
unsigned char *data;
int newctrl;
int status;
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;
}
if (!ACM_READY(acm))
goto exit;
data = (unsigned char *)(dr + 1);
switch (dr->bNotificationType) {
case USB_CDC_NOTIFY_NETWORK_CONNECTION:
dbg("%s network", dr->wValue ? "connected to" : "disconnected from");
break;
case USB_CDC_NOTIFY_SERIAL_STATE:
newctrl = le16_to_cpu(get_unaligned((__le16 *) data));
if (acm->tty && !acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
dbg("calling hangup");
tty_hangup(acm->tty);
}
acm->ctrlin = newctrl;
dbg("input control lines: dcd%c dsr%c break%c ring%c framing%c parity%c overrun%c",
acm->ctrlin & ACM_CTRL_DCD ? '+' : '-', acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
acm->ctrlin & ACM_CTRL_BRK ? '+' : '-', acm->ctrlin & ACM_CTRL_RI ? '+' : '-',
acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-', acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',
acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');
break;
default:
dbg("unknown notification %d received: index %d len %d data0 %d data1 %d",
dr->bNotificationType, dr->wIndex,
dr->wLength, data[0], data[1]);
break;
}
exit:
status = usb_submit_urb (urb, GFP_ATOMIC);
if (status)
err ("%s - usb_submit_urb failed with result %d",
__FUNCTION__, status);
}
/* data interface returns incoming bytes, or we got unthrottled */
static void acm_read_bulk(struct urb *urb, struct pt_regs *regs)
{
struct acm_rb *buf;
struct acm_ru *rcv = urb->context;
struct acm *acm = rcv->instance;
dbg("Entering acm_read_bulk with status %d\n", urb->status);
if (!ACM_READY(acm))
return;
if (urb->status)
dev_dbg(&acm->data->dev, "bulk rx status %d\n", urb->status);
buf = rcv->buffer;
buf->size = urb->actual_length;
spin_lock(&acm->read_lock);
list_add_tail(&rcv->list, &acm->spare_read_urbs);
list_add_tail(&buf->list, &acm->filled_read_bufs);
spin_unlock(&acm->read_lock);
tasklet_schedule(&acm->urb_task);
}
static void acm_rx_tasklet(unsigned long _acm)
{
struct acm *acm = (void *)_acm;
struct acm_rb *buf;
struct tty_struct *tty = acm->tty;
struct acm_ru *rcv;
//unsigned long flags;
int i = 0;
dbg("Entering acm_rx_tasklet");
if (!ACM_READY(acm) || acm->throttle)
return;
next_buffer:
spin_lock(&acm->read_lock);
if (list_empty(&acm->filled_read_bufs)) {
spin_unlock(&acm->read_lock);
goto urbs;
}
buf = list_entry(acm->filled_read_bufs.next,
struct acm_rb, list);
list_del(&buf->list);
spin_unlock(&acm->read_lock);
dbg("acm_rx_tasklet: procesing buf 0x%p, size = %d\n", buf, buf->size);
tty_buffer_request_room(tty, buf->size);
if (!acm->throttle)
tty_insert_flip_string(tty, buf->base, buf->size);
tty_flip_buffer_push(tty);
spin_lock(&acm->throttle_lock);
if (acm->throttle) {
dbg("Throtteling noticed");
memmove(buf->base, buf->base + i, buf->size - i);
buf->size -= i;
spin_unlock(&acm->throttle_lock);
spin_lock(&acm->read_lock);
list_add(&buf->list, &acm->filled_read_bufs);
spin_unlock(&acm->read_lock);
return;
}
spin_unlock(&acm->throttle_lock);
spin_lock(&acm->read_lock);
list_add(&buf->list, &acm->spare_read_bufs);
spin_unlock(&acm->read_lock);
goto next_buffer;
urbs:
while (!list_empty(&acm->spare_read_bufs)) {
spin_lock(&acm->read_lock);
if (list_empty(&acm->spare_read_urbs)) {
spin_unlock(&acm->read_lock);
return;
}
rcv = list_entry(acm->spare_read_urbs.next,
struct acm_ru, list);
list_del(&rcv->list);
spin_unlock(&acm->read_lock);
buf = list_entry(acm->spare_read_bufs.next,
struct acm_rb, list);
list_del(&buf->list);
rcv->buffer = buf;
usb_fill_bulk_urb(rcv->urb, acm->dev,
acm->rx_endpoint,
buf->base,
acm->readsize,
acm_read_bulk, rcv);
rcv->urb->transfer_dma = buf->dma;
rcv->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
dbg("acm_rx_tasklet: sending urb 0x%p, rcv 0x%p, buf 0x%p\n", rcv->urb, rcv, buf);
/* This shouldn't kill the driver as unsuccessful URBs are returned to the
free-urbs-pool and resubmited ASAP */
if (usb_submit_urb(rcv->urb, GFP_ATOMIC) < 0) {
list_add(&buf->list, &acm->spare_read_bufs);
spin_lock(&acm->read_lock);
list_add(&rcv->list, &acm->spare_read_urbs);
spin_unlock(&acm->read_lock);
return;
}
}
}
/* data interface wrote those outgoing bytes */
static void acm_write_bulk(struct urb *urb, struct pt_regs *regs)
{
struct acm *acm = (struct acm *)urb->context;
dbg("Entering acm_write_bulk with status %d\n", urb->status);
acm_write_done(acm);
acm_write_start(acm);
if (ACM_READY(acm))
schedule_work(&acm->work);
}
static void acm_softint(void *private)
{
struct acm *acm = private;
dbg("Entering acm_softint.\n");
if (!ACM_READY(acm))
return;
tty_wakeup(acm->tty);
}
/*
* TTY handlers
*/
static int acm_tty_open(struct tty_struct *tty, struct file *filp)
{
struct acm *acm;
int rv = -EINVAL;
int i;
dbg("Entering acm_tty_open.\n");
down(&open_sem);
acm = acm_table[tty->index];
if (!acm || !acm->dev)
goto err_out;
else
rv = 0;
tty->driver_data = acm;
acm->tty = tty;
/* force low_latency on so that our tty_push actually forces the data through,
otherwise it is scheduled, and with high data rates data can get lost. */
tty->low_latency = 1;
if (acm->used++) {
goto done;
}
acm->ctrlurb->dev = acm->dev;
if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
dbg("usb_submit_urb(ctrl irq) failed");
goto bail_out;
}
if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS))
goto full_bailout;
INIT_LIST_HEAD(&acm->spare_read_urbs);
INIT_LIST_HEAD(&acm->spare_read_bufs);
INIT_LIST_HEAD(&acm->filled_read_bufs);
for (i = 0; i < ACM_NRU; i++) {
list_add(&(acm->ru[i].list), &acm->spare_read_urbs);
}
for (i = 0; i < ACM_NRB; i++) {
list_add(&(acm->rb[i].list), &acm->spare_read_bufs);
}
tasklet_schedule(&acm->urb_task);
done:
err_out:
up(&open_sem);
return rv;
full_bailout:
usb_kill_urb(acm->ctrlurb);
bail_out:
acm->used--;
up(&open_sem);
return -EIO;
}
static void acm_tty_unregister(struct acm *acm)
{
int i;
tty_unregister_device(acm_tty_driver, acm->minor);
usb_put_intf(acm->control);
acm_table[acm->minor] = NULL;
usb_free_urb(acm->ctrlurb);
usb_free_urb(acm->writeurb);
for (i = 0; i < ACM_NRU; i++)
usb_free_urb(acm->ru[i].urb);
kfree(acm);
}
static void acm_tty_close(struct tty_struct *tty, struct file *filp)
{
struct acm *acm = tty->driver_data;
int i;
if (!acm || !acm->used)
return;
down(&open_sem);
if (!--acm->used) {
if (acm->dev) {
acm_set_control(acm, acm->ctrlout = 0);
usb_kill_urb(acm->ctrlurb);
usb_kill_urb(acm->writeurb);
for (i = 0; i < ACM_NRU; i++)
usb_kill_urb(acm->ru[i].urb);
} else
acm_tty_unregister(acm);
}
up(&open_sem);
}
static int acm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
struct acm *acm = tty->driver_data;
int stat;
unsigned long flags;
int wbn;
struct acm_wb *wb;
dbg("Entering acm_tty_write to write %d bytes,\n", count);
if (!ACM_READY(acm))
return -EINVAL;
if (!count)
return 0;
spin_lock_irqsave(&acm->write_lock, flags);
if ((wbn = acm_wb_alloc(acm)) < 0) {
spin_unlock_irqrestore(&acm->write_lock, flags);
acm_write_start(acm);
return 0;
}
wb = &acm->wb[wbn];
count = (count > acm->writesize) ? acm->writesize : count;
dbg("Get %d bytes...", count);
memcpy(wb->buf, buf, count);
wb->len = count;
spin_unlock_irqrestore(&acm->write_lock, flags);
if ((stat = acm_write_start(acm)) < 0)
return stat;
return count;
}
static int acm_tty_write_room(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return -EINVAL;
/*
* Do not let the line discipline to know that we have a reserve,
* or it might get too enthusiastic.
*/
return (acm->write_ready && acm_wb_is_avail(acm)) ? acm->writesize : 0;
}
static int acm_tty_chars_in_buffer(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return -EINVAL;
/*
* This is inaccurate (overcounts), but it works.
*/
return (ACM_NWB - acm_wb_is_avail(acm)) * acm->writesize;
}
static void acm_tty_throttle(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return;
spin_lock_bh(&acm->throttle_lock);
acm->throttle = 1;
spin_unlock_bh(&acm->throttle_lock);
}
static void acm_tty_unthrottle(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return;
spin_lock_bh(&acm->throttle_lock);
acm->throttle = 0;
spin_unlock_bh(&acm->throttle_lock);
tasklet_schedule(&acm->urb_task);
}
static void acm_tty_break_ctl(struct tty_struct *tty, int state)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return;
if (acm_send_break(acm, state ? 0xffff : 0))
dbg("send break failed");
}
static int acm_tty_tiocmget(struct tty_struct *tty, struct file *file)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return -EINVAL;
return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
(acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
(acm->ctrlin & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
(acm->ctrlin & ACM_CTRL_RI ? TIOCM_RI : 0) |
(acm->ctrlin & ACM_CTRL_DCD ? TIOCM_CD : 0) |
TIOCM_CTS;
}
static int acm_tty_tiocmset(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear)
{
struct acm *acm = tty->driver_data;
unsigned int newctrl;
if (!ACM_READY(acm))
return -EINVAL;
newctrl = acm->ctrlout;
set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) | (set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) | (clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);
newctrl = (newctrl & ~clear) | set;
if (acm->ctrlout == newctrl)
return 0;
return acm_set_control(acm, acm->ctrlout = newctrl);
}
static int acm_tty_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg)
{
struct acm *acm = tty->driver_data;
if (!ACM_READY(acm))
return -EINVAL;
return -ENOIOCTLCMD;
}
static const __u32 acm_tty_speed[] = {
0, 50, 75, 110, 134, 150, 200, 300, 600,
1200, 1800, 2400, 4800, 9600, 19200, 38400,
57600, 115200, 230400, 460800, 500000, 576000,
921600, 1000000, 1152000, 1500000, 2000000,
2500000, 3000000, 3500000, 4000000
};
static const __u8 acm_tty_size[] = {
5, 6, 7, 8
};
static void acm_tty_set_termios(struct tty_struct *tty, struct termios *termios_old)
{
struct acm *acm = tty->driver_data;
struct termios *termios = tty->termios;
struct usb_cdc_line_coding newline;
int newctrl = acm->ctrlout;
if (!ACM_READY(acm))
return;
newline.dwDTERate = cpu_to_le32p(acm_tty_speed +
(termios->c_cflag & CBAUD & ~CBAUDEX) + (termios->c_cflag & CBAUDEX ? 15 : 0));
newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
newline.bParityType = termios->c_cflag & PARENB ?
(termios->c_cflag & PARODD ? 1 : 2) + (termios->c_cflag & CMSPAR ? 2 : 0) : 0;
newline.bDataBits = acm_tty_size[(termios->c_cflag & CSIZE) >> 4];
acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
if (!newline.dwDTERate) {
newline.dwDTERate = acm->line.dwDTERate;
newctrl &= ~ACM_CTRL_DTR;
} else newctrl |= ACM_CTRL_DTR;
if (newctrl != acm->ctrlout)
acm_set_control(acm, acm->ctrlout = newctrl);
if (memcmp(&acm->line, &newline, sizeof newline)) {
memcpy(&acm->line, &newline, sizeof newline);
dbg("set line: %d %d %d %d", le32_to_cpu(newline.dwDTERate),
newline.bCharFormat, newline.bParityType,
newline.bDataBits);
acm_set_line(acm, &acm->line);
}
}
/*
* USB probe and disconnect routines.
*/
/* Little helper: write buffers free */
static void acm_write_buffers_free(struct acm *acm)
{
int i;
struct acm_wb *wb;
for (wb = &acm->wb[0], i = 0; i < ACM_NWB; i++, wb++) {
usb_buffer_free(acm->dev, acm->writesize, wb->buf, wb->dmah);
}
}
/* Little helper: write buffers allocate */
static int acm_write_buffers_alloc(struct acm *acm)
{
int i;
struct acm_wb *wb;
for (wb = &acm->wb[0], i = 0; i < ACM_NWB; i++, wb++) {
wb->buf = usb_buffer_alloc(acm->dev, acm->writesize, GFP_KERNEL,
&wb->dmah);
if (!wb->buf) {
while (i != 0) {
--i;
--wb;
usb_buffer_free(acm->dev, acm->writesize,
wb->buf, wb->dmah);
}
return -ENOMEM;
}
}
return 0;
}
static int acm_probe (struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_cdc_union_desc *union_header = NULL;
char *buffer = intf->altsetting->extra;
int buflen = intf->altsetting->extralen;
struct usb_interface *control_interface;
struct usb_interface *data_interface;
struct usb_endpoint_descriptor *epctrl;
struct usb_endpoint_descriptor *epread;
struct usb_endpoint_descriptor *epwrite;
struct usb_device *usb_dev = interface_to_usbdev(intf);
struct acm *acm;
int minor;
int ctrlsize,readsize;
u8 *buf;
u8 ac_management_function = 0;
u8 call_management_function = 0;
int call_interface_num = -1;
int data_interface_num;
unsigned long quirks;
int i;
/* handle quirks deadly to normal probing*/
quirks = (unsigned long)id->driver_info;
if (quirks == NO_UNION_NORMAL) {
data_interface = usb_ifnum_to_if(usb_dev, 1);
control_interface = usb_ifnum_to_if(usb_dev, 0);
goto skip_normal_probe;
}
/* normal probing*/
if (!buffer) {
err("Wierd descriptor references\n");
return -EINVAL;
}
if (!buflen) {
if (intf->cur_altsetting->endpoint->extralen && intf->cur_altsetting->endpoint->extra) {
dev_dbg(&intf->dev,"Seeking extra descriptors on endpoint\n");
buflen = intf->cur_altsetting->endpoint->extralen;
buffer = intf->cur_altsetting->endpoint->extra;
} else {
err("Zero length descriptor references\n");
return -EINVAL;
}
}
while (buflen > 0) {
if (buffer [1] != USB_DT_CS_INTERFACE) {
err("skipping garbage\n");
goto next_desc;
}
switch (buffer [2]) {
case USB_CDC_UNION_TYPE: /* we've found it */
if (union_header) {
err("More than one union descriptor, skipping ...");
goto next_desc;
}
union_header = (struct usb_cdc_union_desc *)
buffer;
break;
case USB_CDC_COUNTRY_TYPE: /* maybe somehow export */
break; /* for now we ignore it */
case USB_CDC_HEADER_TYPE: /* maybe check version */
break; /* for now we ignore it */
case USB_CDC_ACM_TYPE:
ac_management_function = buffer[3];
break;
case USB_CDC_CALL_MANAGEMENT_TYPE:
call_management_function = buffer[3];
call_interface_num = buffer[4];
if ((call_management_function & 3) != 3)
err("This device cannot do calls on its own. It is no modem.");
break;
default:
err("Ignoring extra header, type %d, length %d", buffer[2], buffer[0]);
break;
}
next_desc:
buflen -= buffer[0];
buffer += buffer[0];
}
if (!union_header) {
if (call_interface_num > 0) {
dev_dbg(&intf->dev,"No union descriptor, using call management descriptor\n");
data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
control_interface = intf;
} else {
dev_dbg(&intf->dev,"No union descriptor, giving up\n");
return -ENODEV;
}
} else {
control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
if (!control_interface || !data_interface) {
dev_dbg(&intf->dev,"no interfaces\n");
return -ENODEV;
}
}
if (data_interface_num != call_interface_num)
dev_dbg(&intf->dev,"Seperate call control interface. That is not fully supported.\n");
skip_normal_probe:
/*workaround for switched interfaces */
if (data_interface->cur_altsetting->desc.bInterfaceClass != CDC_DATA_INTERFACE_TYPE) {
if (control_interface->cur_altsetting->desc.bInterfaceClass == CDC_DATA_INTERFACE_TYPE) {
struct usb_interface *t;
dev_dbg(&intf->dev,"Your device has switched interfaces.\n");
t = control_interface;
control_interface = data_interface;
data_interface = t;
} else {
return -EINVAL;
}
}
if (usb_interface_claimed(data_interface)) { /* valid in this context */
dev_dbg(&intf->dev,"The data interface isn't available\n");
return -EBUSY;
}
if (data_interface->cur_altsetting->desc.bNumEndpoints < 2)
return -EINVAL;
epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
epread = &data_interface->cur_altsetting->endpoint[0].desc;
epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
/* workaround for switched endpoints */
if ((epread->bEndpointAddress & USB_DIR_IN) != USB_DIR_IN) {
/* descriptors are swapped */
struct usb_endpoint_descriptor *t;
dev_dbg(&intf->dev,"The data interface has switched endpoints\n");
t = epread;
epread = epwrite;
epwrite = t;
}
dbg("interfaces are valid");
for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
if (minor == ACM_TTY_MINORS) {
err("no more free acm devices");
return -ENODEV;
}
if (!(acm = kzalloc(sizeof(struct acm), GFP_KERNEL))) {
dev_dbg(&intf->dev, "out of memory (acm kzalloc)\n");
goto alloc_fail;
}
ctrlsize = le16_to_cpu(epctrl->wMaxPacketSize);
readsize = le16_to_cpu(epread->wMaxPacketSize)*2;
acm->writesize = le16_to_cpu(epwrite->wMaxPacketSize);
acm->control = control_interface;
acm->data = data_interface;
acm->minor = minor;
acm->dev = usb_dev;
acm->ctrl_caps = ac_management_function;
acm->ctrlsize = ctrlsize;
acm->readsize = readsize;
acm->urb_task.func = acm_rx_tasklet;
acm->urb_task.data = (unsigned long) acm;
INIT_WORK(&acm->work, acm_softint, acm);
spin_lock_init(&acm->throttle_lock);
spin_lock_init(&acm->write_lock);
spin_lock_init(&acm->read_lock);
acm->write_ready = 1;
acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
buf = usb_buffer_alloc(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
if (!buf) {
dev_dbg(&intf->dev, "out of memory (ctrl buffer alloc)\n");
goto alloc_fail2;
}
acm->ctrl_buffer = buf;
if (acm_write_buffers_alloc(acm) < 0) {
dev_dbg(&intf->dev, "out of memory (write buffer alloc)\n");
goto alloc_fail4;
}
acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
if (!acm->ctrlurb) {
dev_dbg(&intf->dev, "out of memory (ctrlurb kmalloc)\n");
goto alloc_fail5;
}
for (i = 0; i < ACM_NRU; i++) {
struct acm_ru *rcv = &(acm->ru[i]);
if (!(rcv->urb = usb_alloc_urb(0, GFP_KERNEL))) {
dev_dbg(&intf->dev, "out of memory (read urbs usb_alloc_urb)\n");
goto alloc_fail7;
}
rcv->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
rcv->instance = acm;
}
for (i = 0; i < ACM_NRB; i++) {
struct acm_rb *buf = &(acm->rb[i]);
// Using usb_buffer_alloc instead of kmalloc as Oliver suggested
if (!(buf->base = usb_buffer_alloc(acm->dev, readsize, GFP_KERNEL, &buf->dma))) {
dev_dbg(&intf->dev, "out of memory (read bufs usb_buffer_alloc)\n");
goto alloc_fail7;
}
}
acm->writeurb = usb_alloc_urb(0, GFP_KERNEL);
if (!acm->writeurb) {
dev_dbg(&intf->dev, "out of memory (writeurb kmalloc)\n");
goto alloc_fail7;
}
usb_fill_int_urb(acm->ctrlurb, usb_dev, usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm, epctrl->bInterval);
acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
acm->ctrlurb->transfer_dma = acm->ctrl_dma;
usb_fill_bulk_urb(acm->writeurb, usb_dev, usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
NULL, acm->writesize, acm_write_bulk, acm);
acm->writeurb->transfer_flags |= URB_NO_FSBR | URB_NO_TRANSFER_DMA_MAP;
dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
acm_set_control(acm, acm->ctrlout);
acm->line.dwDTERate = cpu_to_le32(9600);
acm->line.bDataBits = 8;
acm_set_line(acm, &acm->line);
usb_driver_claim_interface(&acm_driver, data_interface, acm);
usb_get_intf(control_interface);
tty_register_device(acm_tty_driver, minor, &control_interface->dev);
acm_table[minor] = acm;
usb_set_intfdata (intf, acm);
return 0;
alloc_fail7:
for (i = 0; i < ACM_NRB; i++)
usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
for (i = 0; i < ACM_NRU; i++)
usb_free_urb(acm->ru[i].urb);
usb_free_urb(acm->ctrlurb);
alloc_fail5:
acm_write_buffers_free(acm);
alloc_fail4:
usb_buffer_free(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
alloc_fail2:
kfree(acm);
alloc_fail:
return -ENOMEM;
}
static void acm_disconnect(struct usb_interface *intf)
{
struct acm *acm = usb_get_intfdata (intf);
struct usb_device *usb_dev = interface_to_usbdev(intf);
int i;
if (!acm || !acm->dev) {
dbg("disconnect on nonexisting interface");
return;
}
down(&open_sem);
acm->dev = NULL;
usb_set_intfdata (intf, NULL);
tasklet_disable(&acm->urb_task);
usb_kill_urb(acm->ctrlurb);
usb_kill_urb(acm->writeurb);
for (i = 0; i < ACM_NRU; i++)
usb_kill_urb(acm->ru[i].urb);
INIT_LIST_HEAD(&acm->filled_read_bufs);
INIT_LIST_HEAD(&acm->spare_read_bufs);
tasklet_enable(&acm->urb_task);
flush_scheduled_work(); /* wait for acm_softint */
acm_write_buffers_free(acm);
usb_buffer_free(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
for (i = 0; i < ACM_NRB; i++)
usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
usb_driver_release_interface(&acm_driver, acm->data);
if (!acm->used) {
acm_tty_unregister(acm);
up(&open_sem);
return;
}
up(&open_sem);
if (acm->tty)
tty_hangup(acm->tty);
}
/*
* USB driver structure.
*/
static struct usb_device_id acm_ids[] = {
/* quirky and broken devices */
{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
},
{ USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
},
/* control interfaces with various AT-command sets */
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_V25TER) },
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_PCCA101) },
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_GSM) },
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_3G ) },
{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
USB_CDC_ACM_PROTO_AT_CDMA) },
/* NOTE: COMM/ACM/0xff is likely MSFT RNDIS ... NOT a modem!! */
{ }
};
MODULE_DEVICE_TABLE (usb, acm_ids);
static struct usb_driver acm_driver = {
.name = "cdc_acm",
.probe = acm_probe,
.disconnect = acm_disconnect,
.id_table = acm_ids,
};
/*
* TTY driver structures.
*/
static struct tty_operations acm_ops = {
.open = acm_tty_open,
.close = acm_tty_close,
.write = acm_tty_write,
.write_room = acm_tty_write_room,
.ioctl = acm_tty_ioctl,
.throttle = acm_tty_throttle,
.unthrottle = acm_tty_unthrottle,
.chars_in_buffer = acm_tty_chars_in_buffer,
.break_ctl = acm_tty_break_ctl,
.set_termios = acm_tty_set_termios,
.tiocmget = acm_tty_tiocmget,
.tiocmset = acm_tty_tiocmset,
};
/*
* Init / exit.
*/
static int __init acm_init(void)
{
int retval;
acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
if (!acm_tty_driver)
return -ENOMEM;
acm_tty_driver->owner = THIS_MODULE,
acm_tty_driver->driver_name = "acm",
acm_tty_driver->name = "ttyACM",
acm_tty_driver->devfs_name = "usb/acm/",
acm_tty_driver->major = ACM_TTY_MAJOR,
acm_tty_driver->minor_start = 0,
acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
acm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS,
acm_tty_driver->init_termios = tty_std_termios;
acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
tty_set_operations(acm_tty_driver, &acm_ops);
retval = tty_register_driver(acm_tty_driver);
if (retval) {
put_tty_driver(acm_tty_driver);
return retval;
}
retval = usb_register(&acm_driver);
if (retval) {
tty_unregister_driver(acm_tty_driver);
put_tty_driver(acm_tty_driver);
return retval;
}
info(DRIVER_VERSION ":" DRIVER_DESC);
return 0;
}
static void __exit acm_exit(void)
{
usb_deregister(&acm_driver);
tty_unregister_driver(acm_tty_driver);
put_tty_driver(acm_tty_driver);
}
module_init(acm_init);
module_exit(acm_exit);
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");
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