cdc-acm.c

omap3 linux 2.6 用nocc去除了冗余代码

				  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", 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_irqsave(&acm->read_lock, flags);
			list_add(&rcv->list, &acm->spare_read_urbs);
			spin_unlock_irqrestore(&acm->read_lock, flags);
			return;
		}
	}
}

/* data interface wrote those outgoing bytes */
static void acm_write_bulk(struct urb *urb)
{
	struct acm *acm = (struct acm *)urb->context;

	dbg("Entering acm_write_bulk with status %d", urb->status);

	acm_write_done(acm);
	acm_write_start(acm);
	if (ACM_READY(acm))
		schedule_work(&acm->work);
}

static void acm_softint(struct work_struct *work)
{
	struct acm *acm = container_of(work, struct acm, work);
	dbg("Entering acm_softint.");
	
	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.");

	mutex_lock(&open_mutex);

	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) &&
	    (acm->ctrl_caps & USB_CDC_CAP_LINE))
		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->rx_buflimit; i++) {
		list_add(&(acm->ru[i].list), &acm->spare_read_urbs);
	}
	for (i = 0; i < acm->rx_buflimit; i++) {
		list_add(&(acm->rb[i].list), &acm->spare_read_bufs);
	}

	acm->throttle = 0;

	tasklet_schedule(&acm->urb_task);

done:
err_out:
	mutex_unlock(&open_mutex);
	return rv;

full_bailout:
	usb_kill_urb(acm->ctrlurb);
bail_out:
	acm->used--;
	mutex_unlock(&open_mutex);
	return -EIO;
}

static void acm_tty_unregister(struct acm *acm)
{
	int i,nr;

	nr = acm->rx_buflimit;
	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 < nr; i++)
		usb_free_urb(acm->ru[i].urb);
	kfree(acm->country_codes);
	kfree(acm);
}

static void acm_tty_close(struct tty_struct *tty, struct file *filp)
{
	struct acm *acm = tty->driver_data;
	int i,nr;

	if (!acm || !acm->used)
		return;

	nr = acm->rx_buflimit;
	mutex_lock(&open_mutex);
	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 < nr; i++)
				usb_kill_urb(acm->ru[i].urb);
		} else
			acm_tty_unregister(acm);
	}
	mutex_unlock(&open_mutex);
}

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,", 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_NW - 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 ktermios *termios_old)
{
	struct acm *acm = tty->driver_data;
	struct ktermios *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_NW; 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_NW; 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;
	struct usb_cdc_country_functional_desc *cfd = 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 num_rx_buf;
	int i;

	/* normal quirks */
	quirks = (unsigned long)id->driver_info;
	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;

	/* handle quirks deadly to normal probing*/
	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");
			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 ...");