1 files changed, 200 insertions, 279 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index e057e5381465..395a347f2ebb 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -7,35 +7,12 @@
  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
  * Copyright (c) 2004 Oliver Neukum     <oliver@neukum.name>
  * Copyright (c) 2005 David Kubicek     <dave@awk.cz>
+ * Copyright (c) 2011 Johan Hovold      <jhovold@gmail.com>
  *
  * 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
- *      v0.26 - multiple write urbs, writesize increased
- */
-
-/*
  * 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
@@ -74,13 +51,7 @@
 #include "cdc-acm.h"
 
 
-#define ACM_CLOSE_TIMEOUT       15      /* seconds to let writes drain */
-
-/*
- * Version Information
- */
-#define DRIVER_VERSION "v0.26"
-#define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek"
+#define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
 
 static struct usb_driver acm_driver;
@@ -94,12 +65,6 @@ static DEFINE_MUTEX(open_mutex);
 static const struct tty_port_operations acm_port_ops = {
 };
 
-#ifdef VERBOSE_DEBUG
-#define verbose 1
-#else
-#define verbose 0
-#endif
-
 /*
  * Functions for ACM control messages.
  */
@@ -111,8 +76,9 @@ static int acm_ctrl_msg(struct acm *acm, int request, int value,
                 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);
+        dev_dbg(&acm->control->dev,
+                        "%s - rq 0x%02x, val %#x, len %#x, result %d\n",
+                        __func__, request, value, len, retval);
         return retval < 0 ? retval : 0;
 }
 
@@ -192,7 +158,9 @@ static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
 
         rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
         if (rc < 0) {
-                dbg("usb_submit_urb(write bulk) failed: %d", rc);
+                dev_err(&acm->data->dev,
+                        "%s - usb_submit_urb(write bulk) failed: %d\n",
+                        __func__, rc);
                 acm_write_done(acm, wb);
         }
         return rc;
@@ -211,7 +179,8 @@ static int acm_write_start(struct acm *acm, int wbn)
                 return -ENODEV;
         }
 
-        dbg("%s susp_count: %d", __func__, acm->susp_count);
+        dev_vdbg(&acm->data->dev, "%s - susp_count %d\n", __func__,
+                                                        acm->susp_count);
         usb_autopm_get_interface_async(acm->control);
         if (acm->susp_count) {
                 if (!acm->delayed_wb)
@@ -287,10 +256,14 @@ static void acm_ctrl_irq(struct urb *urb)
         case -ENOENT:
         case -ESHUTDOWN:
                 /* this urb is terminated, clean up */
-                dbg("%s - urb shutting down with status: %d", __func__, status);
+                dev_dbg(&acm->control->dev,
+                                "%s - urb shutting down with status: %d\n",
+                                __func__, status);
                 return;
         default:
-                dbg("%s - nonzero urb status received: %d", __func__, status);
+                dev_dbg(&acm->control->dev,
+                                "%s - nonzero urb status received: %d\n",
+                                __func__, status);
                 goto exit;
         }
 
@@ -302,8 +275,8 @@ static void acm_ctrl_irq(struct urb *urb)
         data = (unsigned char *)(dr + 1);
         switch (dr->bNotificationType) {
         case USB_CDC_NOTIFY_NETWORK_CONNECTION:
-                dbg("%s network", dr->wValue ?
-                                        "connected to" : "disconnected from");
+                dev_dbg(&acm->control->dev, "%s - network connection: %d\n",
+                                                        __func__, dr->wValue);
                 break;
 
         case USB_CDC_NOTIFY_SERIAL_STATE:
@@ -313,7 +286,8 @@ static void acm_ctrl_irq(struct urb *urb)
                 if (tty) {
                         if (!acm->clocal &&
                                 (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
-                                dbg("calling hangup");
+                                dev_dbg(&acm->control->dev,
+                                        "%s - calling hangup\n", __func__);
                                 tty_hangup(tty);
                         }
                         tty_kref_put(tty);
@@ -321,7 +295,10 @@ static void acm_ctrl_irq(struct urb *urb)
 
                 acm->ctrlin = newctrl;
 
-                dbg("input control lines: dcd%c dsr%c break%c ring%c framing%c parity%c overrun%c",
+                dev_dbg(&acm->control->dev,
+                        "%s - input control lines: dcd%c dsr%c break%c "
+                        "ring%c framing%c parity%c overrun%c\n",
+                        __func__,
                         acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',
                         acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
                         acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',
@@ -332,7 +309,10 @@ static void acm_ctrl_irq(struct urb *urb)
                         break;
 
         default:
-                dbg("unknown notification %d received: index %d len %d data0 %d data1 %d",
+                dev_dbg(&acm->control->dev,
+                        "%s - unknown notification %d received: index %d "
+                        "len %d data0 %d data1 %d\n",
+                        __func__,
                         dr->bNotificationType, dr->wIndex,
                         dr->wLength, data[0], data[1]);
                 break;
@@ -340,166 +320,96 @@ static void acm_ctrl_irq(struct urb *urb)
 exit:
         retval = usb_submit_urb(urb, GFP_ATOMIC);
         if (retval)
-                dev_err(&urb->dev->dev, "%s - usb_submit_urb failed with "
-                        "result %d", __func__, retval);
+                dev_err(&acm->control->dev, "%s - usb_submit_urb failed: %d\n",
+                                                        __func__, retval);
 }
 
-/* data interface returns incoming bytes, or we got unthrottled */
-static void acm_read_bulk(struct urb *urb)
+static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
 {
-        struct acm_rb *buf;
-        struct acm_ru *rcv = urb->context;
-        struct acm *acm = rcv->instance;
-        int status = urb->status;
+        int res;
+
+        if (!test_and_clear_bit(index, &acm->read_urbs_free))
+                return 0;
 
-        dbg("Entering acm_read_bulk with status %d", status);
+        dev_vdbg(&acm->data->dev, "%s - urb %d\n", __func__, index);
 
-        if (!ACM_READY(acm)) {
-                dev_dbg(&acm->data->dev, "Aborting, acm not ready");
-                return;
+        res = usb_submit_urb(acm->read_urbs[index], mem_flags);
+        if (res) {
+                if (res != -EPERM) {
+                        dev_err(&acm->data->dev,
+                                        "%s - usb_submit_urb failed: %d\n",
+                                        __func__, res);
+                }
+                set_bit(index, &acm->read_urbs_free);
+                return res;
         }
-        usb_mark_last_busy(acm->dev);
 
-        if (status)
-                dev_dbg(&acm->data->dev, "bulk rx status %d\n", status);
+        return 0;
+}
 
-        buf = rcv->buffer;
-        buf->size = urb->actual_length;
+static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
+{
+        int res;
+        int i;
 
-        if (likely(status == 0)) {
-                spin_lock(&acm->read_lock);
-                acm->processing++;
-                list_add_tail(&rcv->list, &acm->spare_read_urbs);
-                list_add_tail(&buf->list, &acm->filled_read_bufs);
-                spin_unlock(&acm->read_lock);
-        } else {
-                /* we drop the buffer due to an error */
-                spin_lock(&acm->read_lock);
-                list_add_tail(&rcv->list, &acm->spare_read_urbs);
-                list_add(&buf->list, &acm->spare_read_bufs);
-                spin_unlock(&acm->read_lock);
-                /* nevertheless the tasklet must be kicked unconditionally
-                so the queue cannot dry up */
+        for (i = 0; i < acm->rx_buflimit; ++i) {
+                res = acm_submit_read_urb(acm, i, mem_flags);
+                if (res)
+                        return res;
         }
-        if (likely(!acm->susp_count))
-                tasklet_schedule(&acm->urb_task);
+
+        return 0;
 }
 
-static void acm_rx_tasklet(unsigned long _acm)
+static void acm_process_read_urb(struct acm *acm, struct urb *urb)
 {
-        struct acm *acm = (void *)_acm;
-        struct acm_rb *buf;
         struct tty_struct *tty;
-        struct acm_ru *rcv;
-        unsigned long flags;
-        unsigned char throttled;
 
-        dbg("Entering acm_rx_tasklet");
-
-        if (!ACM_READY(acm)) {
-                dbg("acm_rx_tasklet: ACM not ready");
+        if (!urb->actual_length)
                 return;
-        }
-
-        spin_lock_irqsave(&acm->throttle_lock, flags);
-        throttled = acm->throttle;
-        spin_unlock_irqrestore(&acm->throttle_lock, flags);
-        if (throttled) {
-                dbg("acm_rx_tasklet: throttled");
-                return;
-        }
 
         tty = tty_port_tty_get(&acm->port);
+        if (!tty)
+                return;
 
-next_buffer:
-        spin_lock_irqsave(&acm->read_lock, flags);
-        if (list_empty(&acm->filled_read_bufs)) {
-                spin_unlock_irqrestore(&acm->read_lock, flags);
-                goto urbs;
-        }
-        buf = list_entry(acm->filled_read_bufs.next,
-                         struct acm_rb, list);
-        list_del(&buf->list);
-        spin_unlock_irqrestore(&acm->read_lock, flags);
-
-        dbg("acm_rx_tasklet: procesing buf 0x%p, size = %d", buf, buf->size);
-
-        if (tty) {
-                spin_lock_irqsave(&acm->throttle_lock, flags);
-                throttled = acm->throttle;
-                spin_unlock_irqrestore(&acm->throttle_lock, flags);
-                if (!throttled) {
-                        tty_insert_flip_string(tty, buf->base, buf->size);
-                        tty_flip_buffer_push(tty);
-                } else {
-                        tty_kref_put(tty);
-                        dbg("Throttling noticed");
-                        spin_lock_irqsave(&acm->read_lock, flags);
-                        list_add(&buf->list, &acm->filled_read_bufs);
-                        spin_unlock_irqrestore(&acm->read_lock, flags);
-                        return;
-                }
-        }
-
-        spin_lock_irqsave(&acm->read_lock, flags);
-        list_add(&buf->list, &acm->spare_read_bufs);
-        spin_unlock_irqrestore(&acm->read_lock, flags);
-        goto next_buffer;
+        tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
+        tty_flip_buffer_push(tty);
 
-urbs:
         tty_kref_put(tty);
+}
 
-        while (!list_empty(&acm->spare_read_bufs)) {
-                spin_lock_irqsave(&acm->read_lock, flags);
-                if (list_empty(&acm->spare_read_urbs)) {
-                        acm->processing = 0;
-                        spin_unlock_irqrestore(&acm->read_lock, flags);
-                        return;
-                }
-                rcv = list_entry(acm->spare_read_urbs.next,
-                                 struct acm_ru, list);
-                list_del(&rcv->list);
-                spin_unlock_irqrestore(&acm->read_lock, flags);
+static void acm_read_bulk_callback(struct urb *urb)
+{
+        struct acm_rb *rb = urb->context;
+        struct acm *acm = rb->instance;
+        unsigned long flags;
 
-                buf = list_entry(acm->spare_read_bufs.next,
-                                 struct acm_rb, list);
-                list_del(&buf->list);
+        dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
+                                        rb->index, urb->actual_length);
+        set_bit(rb->index, &acm->read_urbs_free);
 
-                rcv->buffer = buf;
+        if (!acm->dev) {
+                dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
+                return;
+        }
+        usb_mark_last_busy(acm->dev);
 
-                if (acm->is_int_ep)
-                        usb_fill_int_urb(rcv->urb, acm->dev,
-                                         acm->rx_endpoint,
-                                         buf->base,
-                                         acm->readsize,
-                                         acm_read_bulk, rcv, acm->bInterval);
-                else
-                        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;
-
-                /* This shouldn't kill the driver as unsuccessful URBs are
-                   returned to the free-urbs-pool and resubmited ASAP */
-                spin_lock_irqsave(&acm->read_lock, flags);
-                if (acm->susp_count ||
-                                usb_submit_urb(rcv->urb, GFP_ATOMIC) < 0) {
-                        list_add(&buf->list, &acm->spare_read_bufs);
-                        list_add(&rcv->list, &acm->spare_read_urbs);
-                        acm->processing = 0;
-                        spin_unlock_irqrestore(&acm->read_lock, flags);
-                        return;
-                } else {
-                        spin_unlock_irqrestore(&acm->read_lock, flags);
-                        dbg("acm_rx_tasklet: sending urb 0x%p, rcv 0x%p, buf 0x%p", rcv->urb, rcv, buf);
-                }
+        if (urb->status) {
+                dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
+                                                        __func__, urb->status);
+                return;
         }
+        acm_process_read_urb(acm, urb);
+
+        /* throttle device if requested by tty */
         spin_lock_irqsave(&acm->read_lock, flags);
-        acm->processing = 0;
-        spin_unlock_irqrestore(&acm->read_lock, flags);
+        acm->throttled = acm->throttle_req;
+        if (!acm->throttled && !acm->susp_count) {
+                spin_unlock_irqrestore(&acm->read_lock, flags);
+                acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
+        } else {
+                spin_unlock_irqrestore(&acm->read_lock, flags);
+        }
 }
 
 /* data interface wrote those outgoing bytes */
@@ -509,9 +419,9 @@ static void acm_write_bulk(struct urb *urb)
         struct acm *acm = wb->instance;
         unsigned long flags;
 
-        if (verbose || urb->status
-                        || (urb->actual_length != urb->transfer_buffer_length))
-                dev_dbg(&acm->data->dev, "tx %d/%d bytes -- > %d\n",
+        if (urb->status || (urb->actual_length != urb->transfer_buffer_length))
+                dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
+                        __func__,
                         urb->actual_length,
                         urb->transfer_buffer_length,
                         urb->status);
@@ -521,8 +431,6 @@ static void acm_write_bulk(struct urb *urb)
         spin_unlock_irqrestore(&acm->write_lock, flags);
         if (ACM_READY(acm))
                 schedule_work(&acm->work);
-        else
-                wake_up_interruptible(&acm->drain_wait);
 }
 
 static void acm_softint(struct work_struct *work)
@@ -530,7 +438,8 @@ static void acm_softint(struct work_struct *work)
         struct acm *acm = container_of(work, struct acm, work);
         struct tty_struct *tty;
 
-        dev_vdbg(&acm->data->dev, "tx work\n");
+        dev_vdbg(&acm->data->dev, "%s\n", __func__);
+
         if (!ACM_READY(acm))
                 return;
         tty = tty_port_tty_get(&acm->port);
@@ -548,8 +457,6 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 {
         struct acm *acm;
         int rv = -ENODEV;
-        int i;
-        dbg("Entering acm_tty_open.");
 
         mutex_lock(&open_mutex);
 
@@ -559,6 +466,8 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
         else
                 rv = 0;
 
+        dev_dbg(&acm->control->dev, "%s\n", __func__);
+
         set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
 
         tty->driver_data = acm;
@@ -578,38 +487,28 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 
         acm->ctrlurb->dev = acm->dev;
         if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
-                dbg("usb_submit_urb(ctrl irq) failed");
+                dev_err(&acm->control->dev,
+                        "%s - usb_submit_urb(ctrl irq) failed\n", __func__);
                 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;
+                goto bail_out;
 
         usb_autopm_put_interface(acm->control);
 
-        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;
+        if (acm_submit_read_urbs(acm, GFP_KERNEL))
+                goto bail_out;
 
         set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
         rv = tty_port_block_til_ready(&acm->port, tty, filp);
-        tasklet_schedule(&acm->urb_task);
 
         mutex_unlock(&acm->mutex);
 out:
         mutex_unlock(&open_mutex);
         return rv;
 
-full_bailout:
-        usb_kill_urb(acm->ctrlurb);
 bail_out:
         acm->port.count--;
         mutex_unlock(&acm->mutex);
@@ -622,26 +521,24 @@ early_bail:
 
 static void acm_tty_unregister(struct acm *acm)
 {
-        int i, nr;
+        int i;
 
-        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);
         for (i = 0; i < ACM_NW; i++)
                 usb_free_urb(acm->wb[i].urb);
-        for (i = 0; i < nr; i++)
-                usb_free_urb(acm->ru[i].urb);
+        for (i = 0; i < acm->rx_buflimit; i++)
+                usb_free_urb(acm->read_urbs[i]);
         kfree(acm->country_codes);
         kfree(acm);
 }
 
-static int acm_tty_chars_in_buffer(struct tty_struct *tty);
-
 static void acm_port_down(struct acm *acm)
 {
-        int i, nr = acm->rx_buflimit;
+        int i;
+
         mutex_lock(&open_mutex);
         if (acm->dev) {
                 usb_autopm_get_interface(acm->control);
@@ -649,10 +546,8 @@ static void acm_port_down(struct acm *acm)
                 usb_kill_urb(acm->ctrlurb);
                 for (i = 0; i < ACM_NW; i++)
                         usb_kill_urb(acm->wb[i].urb);
-                tasklet_disable(&acm->urb_task);
-                for (i = 0; i < nr; i++)
-                        usb_kill_urb(acm->ru[i].urb);
-                tasklet_enable(&acm->urb_task);
+                for (i = 0; i < acm->rx_buflimit; i++)
+                        usb_kill_urb(acm->read_urbs[i]);
                 acm->control->needs_remote_wakeup = 0;
                 usb_autopm_put_interface(acm->control);
         }
@@ -698,13 +593,13 @@ static int acm_tty_write(struct tty_struct *tty,
         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;
 
+        dev_vdbg(&acm->data->dev, "%s - count %d\n", __func__, count);
+
         spin_lock_irqsave(&acm->write_lock, flags);
         wbn = acm_wb_alloc(acm);
         if (wbn < 0) {
@@ -714,7 +609,7 @@ static int acm_tty_write(struct tty_struct *tty,
         wb = &acm->wb[wbn];
 
         count = (count > acm->writesize) ? acm->writesize : count;
-        dbg("Get %d bytes...", count);
+        dev_vdbg(&acm->data->dev, "%s - write %d\n", __func__, count);
         memcpy(wb->buf, buf, count);
         wb->len = count;
         spin_unlock_irqrestore(&acm->write_lock, flags);
@@ -751,22 +646,31 @@ static int acm_tty_chars_in_buffer(struct tty_struct *tty)
 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);
+
+        spin_lock_irq(&acm->read_lock);
+        acm->throttle_req = 1;
+        spin_unlock_irq(&acm->read_lock);
 }
 
 static void acm_tty_unthrottle(struct tty_struct *tty)
 {
         struct acm *acm = tty->driver_data;
+        unsigned int was_throttled;
+
         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);
+
+        spin_lock_irq(&acm->read_lock);
+        was_throttled = acm->throttled;
+        acm->throttled = 0;
+        acm->throttle_req = 0;
+        spin_unlock_irq(&acm->read_lock);
+
+        if (was_throttled)
+                acm_submit_read_urbs(acm, GFP_KERNEL);
 }
 
 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
@@ -777,7 +681,8 @@ static int acm_tty_break_ctl(struct tty_struct *tty, int state)
                 return -EINVAL;
         retval = acm_send_break(acm, state ? 0xffff : 0);
         if (retval < 0)
-                dbg("send break failed");
+                dev_dbg(&acm->control->dev, "%s - send break failed\n",
+                                                                __func__);
         return retval;
 }
 
@@ -872,7 +777,9 @@ static void acm_tty_set_termios(struct tty_struct *tty,
 
         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),
+                dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
+                        __func__,
+                        le32_to_cpu(newline.dwDTERate),
                         newline.bCharFormat, newline.bParityType,
                         newline.bDataBits);
                 acm_set_line(acm, &acm->line);
@@ -897,11 +804,11 @@ static void acm_write_buffers_free(struct acm *acm)
 static void acm_read_buffers_free(struct acm *acm)
 {
         struct usb_device *usb_dev = interface_to_usbdev(acm->control);
-        int i, n = acm->rx_buflimit;
+        int i;
 
-        for (i = 0; i < n; i++)
+        for (i = 0; i < acm->rx_buflimit; i++)
                 usb_free_coherent(usb_dev, acm->readsize,
-                                  acm->rb[i].base, acm->rb[i].dma);
+                          acm->read_buffers[i].base, acm->read_buffers[i].dma);
 }
 
 /* Little helper: write buffers allocate */
@@ -946,7 +853,7 @@ static int acm_probe(struct usb_interface *intf,
         u8 ac_management_function = 0;
         u8 call_management_function = 0;
         int call_interface_num = -1;
-        int data_interface_num;
+        int data_interface_num = -1;
         unsigned long quirks;
         int num_rx_buf;
         int i;
@@ -1030,7 +937,11 @@ next_desc:
         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));
+                        /* quirks for Droids MuIn LCD */
+                        if (quirks & NO_DATA_INTERFACE)
+                                data_interface = usb_ifnum_to_if(usb_dev, 0);
+                        else
+                                data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
                         control_interface = intf;
                 } else {
                         if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
@@ -1133,7 +1044,7 @@ skip_normal_probe:
                 epwrite = t;
         }
 made_compressed_probe:
-        dbg("interfaces are valid");
+        dev_dbg(&intf->dev, "interfaces are valid\n");
         for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
 
         if (minor == ACM_TTY_MINORS) {
@@ -1143,7 +1054,7 @@ made_compressed_probe:
 
         acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
         if (acm == NULL) {
-                dev_dbg(&intf->dev, "out of memory (acm kzalloc)\n");
+                dev_err(&intf->dev, "out of memory (acm kzalloc)\n");
                 goto alloc_fail;
         }
 
@@ -1162,11 +1073,7 @@ made_compressed_probe:
         acm->ctrlsize = ctrlsize;
         acm->readsize = readsize;
         acm->rx_buflimit = num_rx_buf;
-        acm->urb_task.func = acm_rx_tasklet;
-        acm->urb_task.data = (unsigned long) acm;
         INIT_WORK(&acm->work, acm_softint);
-        init_waitqueue_head(&acm->drain_wait);
-        spin_lock_init(&acm->throttle_lock);
         spin_lock_init(&acm->write_lock);
         spin_lock_init(&acm->read_lock);
         mutex_init(&acm->mutex);
@@ -1179,53 +1086,69 @@ made_compressed_probe:
 
         buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
         if (!buf) {
-                dev_dbg(&intf->dev, "out of memory (ctrl buffer alloc)\n");
+                dev_err(&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");
+                dev_err(&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");
+                dev_err(&intf->dev, "out of memory (ctrlurb kmalloc)\n");
                 goto alloc_fail5;
         }
         for (i = 0; i < num_rx_buf; i++) {
-                struct acm_ru *rcv = &(acm->ru[i]);
+                struct acm_rb *rb = &(acm->read_buffers[i]);
+                struct urb *urb;
 
-                rcv->urb = usb_alloc_urb(0, GFP_KERNEL);
-                if (rcv->urb == NULL) {
-                        dev_dbg(&intf->dev,
-                                "out of memory (read urbs usb_alloc_urb)\n");
+                rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
+                                                                &rb->dma);
+                if (!rb->base) {
+                        dev_err(&intf->dev, "out of memory "
+                                        "(read bufs usb_alloc_coherent)\n");
                         goto alloc_fail6;
                 }
+                rb->index = i;
+                rb->instance = acm;
 
-                rcv->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-                rcv->instance = acm;
-        }
-        for (i = 0; i < num_rx_buf; i++) {
-                struct acm_rb *rb = &(acm->rb[i]);
-
-                rb->base = usb_alloc_coherent(acm->dev, readsize,
-                                GFP_KERNEL, &rb->dma);
-                if (!rb->base) {
-                        dev_dbg(&intf->dev,
-                                "out of memory (read bufs usb_alloc_coherent)\n");
-                        goto alloc_fail7;
+                urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (!urb) {
+                        dev_err(&intf->dev,
+                                "out of memory (read urbs usb_alloc_urb)\n");
+                        goto alloc_fail6;
+                }
+                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+                urb->transfer_dma = rb->dma;
+                if (acm->is_int_ep) {
+                        usb_fill_int_urb(urb, acm->dev,
+                                         acm->rx_endpoint,
+                                         rb->base,
+                                         acm->readsize,
+                                         acm_read_bulk_callback, rb,
+                                         acm->bInterval);
+                } else {
+                        usb_fill_bulk_urb(urb, acm->dev,
+                                          acm->rx_endpoint,
+                                          rb->base,
+                                          acm->readsize,
+                                          acm_read_bulk_callback, rb);
                 }
+
+                acm->read_urbs[i] = urb;
+                __set_bit(i, &acm->read_urbs_free);
         }
         for (i = 0; i < ACM_NW; i++) {
                 struct acm_wb *snd = &(acm->wb[i]);
 
                 snd->urb = usb_alloc_urb(0, GFP_KERNEL);
                 if (snd->urb == NULL) {
-                        dev_dbg(&intf->dev,
-                                "out of memory (write urbs usb_alloc_urb)");
-                        goto alloc_fail8;
+                        dev_err(&intf->dev,
+                                "out of memory (write urbs usb_alloc_urb)\n");
+                        goto alloc_fail7;
                 }
 
                 if (usb_endpoint_xfer_int(epwrite))
@@ -1244,7 +1167,7 @@ made_compressed_probe:
 
         i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
         if (i < 0)
-                goto alloc_fail8;
+                goto alloc_fail7;
 
         if (cfd) { /* export the country data */
                 acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
@@ -1296,14 +1219,13 @@ skip_countries:
         acm_table[minor] = acm;
 
         return 0;
-alloc_fail8:
+alloc_fail7:
         for (i = 0; i < ACM_NW; i++)
                 usb_free_urb(acm->wb[i].urb);
-alloc_fail7:
-        acm_read_buffers_free(acm);
 alloc_fail6:
         for (i = 0; i < num_rx_buf; i++)
-                usb_free_urb(acm->ru[i].urb);
+                usb_free_urb(acm->read_urbs[i]);
+        acm_read_buffers_free(acm);
         usb_free_urb(acm->ctrlurb);
 alloc_fail5:
         acm_write_buffers_free(acm);
@@ -1318,17 +1240,14 @@ alloc_fail:
 static void stop_data_traffic(struct acm *acm)
 {
         int i;
-        dbg("Entering stop_data_traffic");
 
-        tasklet_disable(&acm->urb_task);
+        dev_dbg(&acm->control->dev, "%s\n", __func__);
 
         usb_kill_urb(acm->ctrlurb);
         for (i = 0; i < ACM_NW; i++)
                 usb_kill_urb(acm->wb[i].urb);
         for (i = 0; i < acm->rx_buflimit; i++)
-                usb_kill_urb(acm->ru[i].urb);
-
-        tasklet_enable(&acm->urb_task);
+                usb_kill_urb(acm->read_urbs[i]);
 
         cancel_work_sync(&acm->work);
 }
@@ -1389,11 +1308,9 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
         if (message.event & PM_EVENT_AUTO) {
                 int b;
 
-                spin_lock_irq(&acm->read_lock);
-                spin_lock(&acm->write_lock);
-                b = acm->processing + acm->transmitting;
-                spin_unlock(&acm->write_lock);
-                spin_unlock_irq(&acm->read_lock);
+                spin_lock_irq(&acm->write_lock);
+                b = acm->transmitting;
+                spin_unlock_irq(&acm->write_lock);
                 if (b)
                         return -EBUSY;
         }
@@ -1455,7 +1372,7 @@ static int acm_resume(struct usb_interface *intf)
                 if (rv < 0)
                         goto err_out;
 
-                tasklet_schedule(&acm->urb_task);
+                rv = acm_submit_read_urbs(acm, GFP_NOIO);
         }
 
 err_out:
@@ -1622,6 +1539,11 @@ static const struct usb_device_id acm_ids[] = {
         .driver_info = NOT_A_MODEM,
         },
 
+        /* Support for Droids MuIn LCD */
+        { USB_DEVICE(0x04d8, 0x000b),
+        .driver_info = NO_DATA_INTERFACE,
+        },
+
         /* control interfaces without any protocol set */
         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
                 USB_CDC_PROTO_NONE) },
@@ -1716,8 +1638,7 @@ static int __init acm_init(void)
                 return retval;
         }
 
-        printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
-               DRIVER_DESC "\n");
+        printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
 
         return 0;
 }