bas-gigaset.c

来自「LINUX 2.6.17.4的源码」· C语言 代码 · 共 2,371 行 · 第 1/5 页

 * return value:
 *	0 on success
 *	-EBUSY if another request is pending
 *	any URB submission error code
 */
static int req_submit(struct bc_state *bcs, int req, int val, int timeout)
{
	struct bas_cardstate *ucs = bcs->cs->hw.bas;
	int ret;
	unsigned long flags;

	gig_dbg(DEBUG_USBREQ, "-------> 0x%02x (%d)", req, val);

	spin_lock_irqsave(&ucs->lock, flags);
	if (ucs->pending) {
		spin_unlock_irqrestore(&ucs->lock, flags);
		dev_err(bcs->cs->dev,
			"submission of request 0x%02x failed: "
			"request 0x%02x still pending\n",
			req, ucs->pending);
		return -EBUSY;
	}

	ucs->dr_ctrl.bRequestType = OUT_VENDOR_REQ;
	ucs->dr_ctrl.bRequest = req;
	ucs->dr_ctrl.wValue = cpu_to_le16(val);
	ucs->dr_ctrl.wIndex = 0;
	ucs->dr_ctrl.wLength = 0;
	usb_fill_control_urb(ucs->urb_ctrl, ucs->udev,
			     usb_sndctrlpipe(ucs->udev, 0),
			     (unsigned char*) &ucs->dr_ctrl, NULL, 0,
			     write_ctrl_callback, ucs);
	if ((ret = usb_submit_urb(ucs->urb_ctrl, SLAB_ATOMIC)) != 0) {
		dev_err(bcs->cs->dev, "could not submit request 0x%02x: %s\n",
			req, get_usb_statmsg(ret));
		spin_unlock_irqrestore(&ucs->lock, flags);
		return ret;
	}
	ucs->pending = req;

	if (timeout > 0) {
		gig_dbg(DEBUG_USBREQ, "setting timeout of %d/10 secs", timeout);
		ucs->timer_ctrl.expires = jiffies + timeout * HZ / 10;
		ucs->timer_ctrl.data = (unsigned long) bcs;
		ucs->timer_ctrl.function = req_timeout;
		add_timer(&ucs->timer_ctrl);
	}

	spin_unlock_irqrestore(&ucs->lock, flags);
	return 0;
}

/* gigaset_init_bchannel
 * called by common.c to connect a B channel
 * initialize isochronous I/O and tell the Gigaset base to open the channel
 * argument:
 *	B channel control structure
 * return value:
 *	0 on success, error code < 0 on error
 */
static int gigaset_init_bchannel(struct bc_state *bcs)
{
	int req, ret;
	unsigned long flags;

	spin_lock_irqsave(&bcs->cs->lock, flags);
	if (unlikely(!bcs->cs->connected)) {
		gig_dbg(DEBUG_USBREQ, "%s: not connected", __func__);
		spin_unlock_irqrestore(&bcs->cs->lock, flags);
		return -ENODEV;
	}

	if ((ret = starturbs(bcs)) < 0) {
		dev_err(bcs->cs->dev,
			"could not start isochronous I/O for channel B%d: %s\n",
			bcs->channel + 1,
			ret == -EFAULT ? "null URB" : get_usb_rcmsg(ret));
		if (ret != -ENODEV)
			error_hangup(bcs);
		spin_unlock_irqrestore(&bcs->cs->lock, flags);
		return ret;
	}

	req = bcs->channel ? HD_OPEN_B2CHANNEL : HD_OPEN_B1CHANNEL;
	if ((ret = req_submit(bcs, req, 0, BAS_TIMEOUT)) < 0) {
		dev_err(bcs->cs->dev, "could not open channel B%d\n",
			bcs->channel + 1);
		stopurbs(bcs->hw.bas);
		if (ret != -ENODEV)
			error_hangup(bcs);
	}

	spin_unlock_irqrestore(&bcs->cs->lock, flags);
	return ret;
}

/* gigaset_close_bchannel
 * called by common.c to disconnect a B channel
 * tell the Gigaset base to close the channel
 * stopping isochronous I/O and LL notification will be done when the
 * acknowledgement for the close arrives
 * argument:
 *	B channel control structure
 * return value:
 *	0 on success, error code < 0 on error
 */
static int gigaset_close_bchannel(struct bc_state *bcs)
{
	int req, ret;
	unsigned long flags;

	spin_lock_irqsave(&bcs->cs->lock, flags);
	if (unlikely(!bcs->cs->connected)) {
		spin_unlock_irqrestore(&bcs->cs->lock, flags);
		gig_dbg(DEBUG_USBREQ, "%s: not connected", __func__);
		return -ENODEV;
	}

	if (!(atomic_read(&bcs->cs->hw.bas->basstate) &
	      (bcs->channel ? BS_B2OPEN : BS_B1OPEN))) {
		/* channel not running: just signal common.c */
		spin_unlock_irqrestore(&bcs->cs->lock, flags);
		gigaset_bchannel_down(bcs);
		return 0;
	}

	/* channel running: tell device to close it */
	req = bcs->channel ? HD_CLOSE_B2CHANNEL : HD_CLOSE_B1CHANNEL;
	if ((ret = req_submit(bcs, req, 0, BAS_TIMEOUT)) < 0)
		dev_err(bcs->cs->dev, "closing channel B%d failed\n",
			bcs->channel + 1);

	spin_unlock_irqrestore(&bcs->cs->lock, flags);
	return ret;
}

/* Device Operations */
/* ================= */

/* complete_cb
 * unqueue first command buffer from queue, waking any sleepers
 * must be called with cs->cmdlock held
 * parameter:
 *	cs	controller state structure
 */
static void complete_cb(struct cardstate *cs)
{
	struct cmdbuf_t *cb = cs->cmdbuf;

	/* unqueue completed buffer */
	cs->cmdbytes -= cs->curlen;
	gig_dbg(DEBUG_TRANSCMD|DEBUG_LOCKCMD,
		"write_command: sent %u bytes, %u left",
		cs->curlen, cs->cmdbytes);
	if ((cs->cmdbuf = cb->next) != NULL) {
		cs->cmdbuf->prev = NULL;
		cs->curlen = cs->cmdbuf->len;
	} else {
		cs->lastcmdbuf = NULL;
		cs->curlen = 0;
	}

	if (cb->wake_tasklet)
		tasklet_schedule(cb->wake_tasklet);

	kfree(cb);
}

/* write_command_callback
 * USB completion handler for AT command transmission
 * called by the USB subsystem in interrupt context
 * parameter:
 *	urb	USB request block of completed request
 *		urb->context = controller state structure
 */
static void write_command_callback(struct urb *urb, struct pt_regs *regs)
{
	struct cardstate *cs = urb->context;
	struct bas_cardstate *ucs = cs->hw.bas;
	unsigned long flags;

	update_basstate(ucs, 0, BS_ATWRPEND);

	/* check status */
	switch (urb->status) {
	case 0:					/* normal completion */
		break;
	case -ENOENT:			/* cancelled */
	case -ECONNRESET:		/* cancelled (async) */
	case -EINPROGRESS:		/* pending */
	case -ENODEV:			/* device removed */
	case -ESHUTDOWN:		/* device shut down */
		/* ignore silently */
		gig_dbg(DEBUG_USBREQ, "%s: %s",
			__func__, get_usb_statmsg(urb->status));
		return;
	default:				/* any failure */
		if (++ucs->retry_cmd_out > BAS_RETRY) {
			dev_warn(cs->dev,
				 "command write: %s, "
				 "giving up after %d retries\n",
				 get_usb_statmsg(urb->status),
				 ucs->retry_cmd_out);
			break;
		}
		if (cs->cmdbuf == NULL) {
			dev_warn(cs->dev,
				 "command write: %s, "
				 "cannot retry - cmdbuf gone\n",
				 get_usb_statmsg(urb->status));
			break;
		}
		dev_notice(cs->dev, "command write: %s, retry %d\n",
			   get_usb_statmsg(urb->status), ucs->retry_cmd_out);
		if (atwrite_submit(cs, cs->cmdbuf->buf, cs->cmdbuf->len) >= 0)
			/* resubmitted - bypass regular exit block */
			return;
		/* command send failed, assume base still waiting */
		update_basstate(ucs, BS_ATREADY, 0);
	}

	spin_lock_irqsave(&cs->cmdlock, flags);
	if (cs->cmdbuf != NULL)
		complete_cb(cs);
	spin_unlock_irqrestore(&cs->cmdlock, flags);
}

/* atrdy_timeout
 * timeout routine for AT command transmission
 * argument:
 *	controller state structure
 */
static void atrdy_timeout(unsigned long data)
{
	struct cardstate *cs = (struct cardstate *) data;
	struct bas_cardstate *ucs = cs->hw.bas;

	dev_warn(cs->dev, "timeout waiting for HD_READY_SEND_ATDATA\n");

	/* fake the missing signal - what else can I do? */
	update_basstate(ucs, BS_ATREADY, BS_ATTIMER);
	start_cbsend(cs);
}

/* atwrite_submit
 * submit an HD_WRITE_ATMESSAGE command URB
 * parameters:
 *	cs	controller state structure
 *	buf	buffer containing command to send
 *	len	length of command to send
 * return value:
 *	0 on success
 *	-EBUSY if another request is pending
 *	any URB submission error code
 */
static int atwrite_submit(struct cardstate *cs, unsigned char *buf, int len)
{
	struct bas_cardstate *ucs = cs->hw.bas;
	int rc;

	gig_dbg(DEBUG_USBREQ, "-------> HD_WRITE_ATMESSAGE (%d)", len);

	if (update_basstate(ucs, BS_ATWRPEND, 0) & BS_ATWRPEND) {
		dev_err(cs->dev,
			"could not submit HD_WRITE_ATMESSAGE: URB busy\n");
		return -EBUSY;
	}

	ucs->dr_cmd_out.bRequestType = OUT_VENDOR_REQ;
	ucs->dr_cmd_out.bRequest = HD_WRITE_ATMESSAGE;
	ucs->dr_cmd_out.wValue = 0;
	ucs->dr_cmd_out.wIndex = 0;
	ucs->dr_cmd_out.wLength = cpu_to_le16(len);
	usb_fill_control_urb(ucs->urb_cmd_out, ucs->udev,
			     usb_sndctrlpipe(ucs->udev, 0),
			     (unsigned char*) &ucs->dr_cmd_out, buf, len,
			     write_command_callback, cs);
	rc = usb_submit_urb(ucs->urb_cmd_out, SLAB_ATOMIC);
	if (unlikely(rc)) {
		update_basstate(ucs, 0, BS_ATWRPEND);
		dev_err(cs->dev, "could not submit HD_WRITE_ATMESSAGE: %s\n",
			get_usb_rcmsg(rc));
		return rc;
	}

	/* submitted successfully, start timeout if necessary */
	if (!(update_basstate(ucs, BS_ATTIMER, BS_ATREADY) & BS_ATTIMER)) {
		gig_dbg(DEBUG_OUTPUT, "setting ATREADY timeout of %d/10 secs",
			ATRDY_TIMEOUT);
		ucs->timer_atrdy.expires = jiffies + ATRDY_TIMEOUT * HZ / 10;
		ucs->timer_atrdy.data = (unsigned long) cs;
		ucs->timer_atrdy.function = atrdy_timeout;
		add_timer(&ucs->timer_atrdy);
	}
	return 0;
}

/* start_cbsend
 * start transmission of AT command queue if necessary
 * parameter:
 *	cs		controller state structure
 * return value:
 *	0 on success
 *	error code < 0 on error
 */
static int start_cbsend(struct cardstate *cs)
{
	struct cmdbuf_t *cb;
	struct bas_cardstate *ucs = cs->hw.bas;
	unsigned long flags;
	int rc;
	int retval = 0;

	/* check if AT channel is open */
	if (!(atomic_read(&ucs->basstate) & BS_ATOPEN)) {
		gig_dbg(DEBUG_TRANSCMD|DEBUG_LOCKCMD, "AT channel not open");
		rc = req_submit(cs->bcs, HD_OPEN_ATCHANNEL, 0, BAS_TIMEOUT);
		if (rc < 0) {
			/* flush command queue */
			spin_lock_irqsave(&cs->cmdlock, flags);
			while (cs->cmdbuf != NULL)
				complete_cb(cs);
			spin_unlock_irqrestore(&cs->cmdlock, flags);
		}
		return rc;
	}

	/* try to send first command in queue */
	spin_lock_irqsave(&cs->cmdlock, flags);

	while ((cb = cs->cmdbuf) != NULL &&
	       atomic_read(&ucs->basstate) & BS_ATREADY) {
		ucs->retry_cmd_out = 0;
		rc = atwrite_submit(cs, cb->buf, cb->len);
		if (unlikely(rc)) {
			retval = rc;
			complete_cb(cs);
		}
	}

	spin_unlock_irqrestore(&cs->cmdlock, flags);
	return retval;
}

/* gigaset_write_cmd
 * This function is called by the device independent part of the driver
 * to transmit an AT command string to the Gigaset device.
 * It encapsulates the device specific method for transmission over the
 * direct USB connection to the base.
 * The command string is added to the queue of commands to send, and
 * USB transmission is started if necessary.
 * parameters:
 *	cs		controller state structure
 *	buf		command string to send
 *	len		number of bytes to send (max. IF_WRITEBUF)
 *	wake_tasklet	tasklet to run when transmission is completed
 *			(NULL if none)
 * return value:
 *	number of bytes queued on success
 *	error code < 0 on error
 */
static int gigaset_write_cmd(struct cardstate *cs,
			     const unsigned char *buf, int len,
			     struct tasklet_struct *wake_tasklet)
{
	struct cmdbuf_t *cb;
	unsigned long flags;
	int status;

	gigaset_dbg_buffer(atomic_read(&cs->mstate) != MS_LOCKED ?
			     DEBUG_TRANSCMD : DEBUG_LOCKCMD,
			   "CMD Transmit", len, buf);

	if (len <= 0)
		return 0;			/* nothing to do */

	if (len > IF_WRITEBUF)
		len = IF_WRITEBUF;
	if (!(cb = kmalloc(sizeof(struct cmdbuf_t) + len, GFP_ATOMIC))) {
		dev_err(cs->dev, "%s: out of memory\n", __func__);
		return -ENOMEM;
	}

	memcpy(cb->buf, buf, len);
	cb->len = len;
	cb->offset = 0;
	cb->next = NULL;
	cb->wake_tasklet = wake_tasklet;

	spin_lock_irqsave(&cs->cmdlock, flags);
	cb->prev = cs->lastcmdbuf;
	if (cs->lastcmdbuf)
		cs->lastcmdbuf->next = cb;
	else {
		cs->cmdbuf = cb;
		cs->curlen = len;
	}
	cs->cmdbytes += len;
	cs->lastcmdbuf = cb;
	spin_unlock_irqrestore(&cs->cmdlock, flags);

	spin_lock_irqsave(&cs->lock, flags);
	if (unlikely(!cs->connected)) {
		spin_unlock_irqrestore(&cs->lock, flags);
		gig_dbg(DEBUG_USBREQ, "%s: not connected", __func__);
		return -ENODEV;
	}
	status = start_cbsend(cs);
	spin_unlock_irqrestore(&cs->lock, flags);
	return status < 0 ? status : len;
}

/* gigaset_write_room
 * tty_driver.write_room interface routine
 * return number of characters the driver will accept to be written via
 * gigaset_write_cmd
 * parameter:
 *	controller state structure
 * return value:
 *	number of characters
 */
static int gigaset_write_room(struct cardstate *cs)
{
	return IF_WRITEBUF;
}

/* gigaset_chars_in_buffer
 * tty_driver.chars_in_buffer interface routine
 * return number of characters waiting to be sent
 * parameter:
 *	controller state structure
 * return value:
 *	number of characters
 */
static int gigaset_chars_in_buffer(struct cardstate *cs)
{
	unsigned long flags;
	unsigned bytes;

	spin_lock_irqsave(&cs->cmdlock, flags);
	bytes = cs->cmdbytes;
	spin_unlock_irqrestore(&cs->cmdlock, flags);

	return bytes;
}

/* gigaset_brkchars
 * implementation of ioctl(GIGASET_BRKCHARS)
 * parameter:
 *	controller state structure
 * return value:
 *	-EINVAL (unimplemented function)
 */
static int gigaset_brkchars(struct cardstate *cs, const unsigned char buf[6])
{
	return -EINVAL;
}


/* Device Initialization/Shutdown */
/* ============================== */

/* Free hardware dependent part of the B channel structure
 * parameter:
 *	bcs	B channel structure
 * return value:
 *	!=0 on success
 */
static int gigaset_freebcshw(struct bc_state *bcs)
{
	struct bas_bc_state *ubc = bcs->hw.bas;
	int i;

	if (!ubc)
		return 0;