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path: root/drivers/usb/class/cdc-acm.c
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Diffstat (limited to 'drivers/usb/class/cdc-acm.c')
-rw-r--r--drivers/usb/class/cdc-acm.c177
1 files changed, 143 insertions, 34 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index c3201affa0b6..95ae6377d7e5 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -159,12 +159,34 @@ static void acm_write_done(struct acm *acm, struct acm_wb *wb)
spin_lock_irqsave(&acm->write_lock, flags);
acm->write_ready = 1;
wb->use = 0;
+ acm->transmitting--;
spin_unlock_irqrestore(&acm->write_lock, flags);
}
/*
* Poke write.
+ *
+ * the caller is responsible for locking
*/
+
+static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
+{
+ int rc;
+
+ acm->transmitting++;
+
+ wb->urb->transfer_buffer = wb->buf;
+ wb->urb->transfer_dma = wb->dmah;
+ wb->urb->transfer_buffer_length = wb->len;
+ wb->urb->dev = acm->dev;
+
+ if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) {
+ dbg("usb_submit_urb(write bulk) failed: %d", rc);
+ acm_write_done(acm, wb);
+ }
+ return rc;
+}
+
static int acm_write_start(struct acm *acm, int wbn)
{
unsigned long flags;
@@ -182,26 +204,31 @@ static int acm_write_start(struct acm *acm, int wbn)
return 0; /* A white lie */
}
+ wb = &acm->wb[wbn];
+ if(acm_wb_is_avail(acm) <= 1)
+ acm->write_ready = 0;
+
+ dbg("%s susp_count: %d", __func__, acm->susp_count);
+ if (acm->susp_count) {
+ acm->old_ready = acm->write_ready;
+ acm->delayed_wb = wb;
+ acm->write_ready = 0;
+ schedule_work(&acm->waker);
+ spin_unlock_irqrestore(&acm->write_lock, flags);
+ return 0; /* A white lie */
+ }
+ usb_mark_last_busy(acm->dev);
+
if (!acm_wb_is_used(acm, wbn)) {
spin_unlock_irqrestore(&acm->write_lock, flags);
return 0;
}
- wb = &acm->wb[wbn];
- if(acm_wb_is_avail(acm) <= 1)
- acm->write_ready = 0;
+ rc = acm_start_wb(acm, wb);
spin_unlock_irqrestore(&acm->write_lock, flags);
- wb->urb->transfer_buffer = wb->buf;
- wb->urb->transfer_dma = wb->dmah;
- wb->urb->transfer_buffer_length = wb->len;
- wb->urb->dev = acm->dev;
-
- if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) {
- dbg("usb_submit_urb(write bulk) failed: %d", rc);
- acm_write_done(acm, wb);
- }
return rc;
+
}
/*
* attributes exported through sysfs
@@ -304,6 +331,7 @@ static void acm_ctrl_irq(struct urb *urb)
break;
}
exit:
+ usb_mark_last_busy(acm->dev);
retval = usb_submit_urb (urb, GFP_ATOMIC);
if (retval)
err ("%s - usb_submit_urb failed with result %d",
@@ -320,8 +348,11 @@ static void acm_read_bulk(struct urb *urb)
dbg("Entering acm_read_bulk with status %d", status);
- if (!ACM_READY(acm))
+ if (!ACM_READY(acm)) {
+ dev_dbg(&acm->data->dev, "Aborting, acm not ready");
return;
+ }
+ usb_mark_last_busy(acm->dev);
if (status)
dev_dbg(&acm->data->dev, "bulk rx status %d\n", status);
@@ -331,6 +362,7 @@ static void acm_read_bulk(struct urb *urb)
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);
@@ -343,7 +375,8 @@ static void acm_read_bulk(struct urb *urb)
/* nevertheless the tasklet must be kicked unconditionally
so the queue cannot dry up */
}
- tasklet_schedule(&acm->urb_task);
+ if (likely(!acm->susp_count))
+ tasklet_schedule(&acm->urb_task);
}
static void acm_rx_tasklet(unsigned long _acm)
@@ -354,16 +387,23 @@ static void acm_rx_tasklet(unsigned long _acm)
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");
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;
+ }
next_buffer:
spin_lock_irqsave(&acm->read_lock, flags);
@@ -403,6 +443,7 @@ urbs:
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;
}
@@ -425,18 +466,23 @@ urbs:
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) {
+ 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);
- spin_lock_irqsave(&acm->read_lock, flags);
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);
}
}
+ spin_lock_irqsave(&acm->read_lock, flags);
+ acm->processing = 0;
+ spin_unlock_irqrestore(&acm->read_lock, flags);
}
/* data interface wrote those outgoing bytes */
@@ -463,6 +509,27 @@ static void acm_softint(struct work_struct *work)
tty_wakeup(acm->tty);
}
+static void acm_waker(struct work_struct *waker)
+{
+ struct acm *acm = container_of(waker, struct acm, waker);
+ long flags;
+ int rv;
+
+ rv = usb_autopm_get_interface(acm->control);
+ if (rv < 0) {
+ err("Autopm failure in %s", __func__);
+ return;
+ }
+ if (acm->delayed_wb) {
+ acm_start_wb(acm, acm->delayed_wb);
+ acm->delayed_wb = NULL;
+ }
+ spin_lock_irqsave(&acm->write_lock, flags);
+ acm->write_ready = acm->old_ready;
+ spin_unlock_irqrestore(&acm->write_lock, flags);
+ usb_autopm_put_interface(acm->control);
+}
+
/*
* TTY handlers
*/
@@ -492,6 +559,8 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
if (usb_autopm_get_interface(acm->control) < 0)
goto early_bail;
+ else
+ acm->control->needs_remote_wakeup = 1;
mutex_lock(&acm->mutex);
if (acm->used++) {
@@ -509,6 +578,7 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) &&
(acm->ctrl_caps & USB_CDC_CAP_LINE))
goto full_bailout;
+ usb_autopm_put_interface(acm->control);
INIT_LIST_HEAD(&acm->spare_read_urbs);
INIT_LIST_HEAD(&acm->spare_read_bufs);
@@ -570,12 +640,14 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp)
mutex_lock(&open_mutex);
if (!--acm->used) {
if (acm->dev) {
+ usb_autopm_get_interface(acm->control);
acm_set_control(acm, acm->ctrlout = 0);
usb_kill_urb(acm->ctrlurb);
for (i = 0; i < ACM_NW; i++)
usb_kill_urb(acm->wb[i].urb);
for (i = 0; i < nr; i++)
usb_kill_urb(acm->ru[i].urb);
+ acm->control->needs_remote_wakeup = 0;
usb_autopm_put_interface(acm->control);
} else
acm_tty_unregister(acm);
@@ -766,7 +838,7 @@ static void acm_tty_set_termios(struct tty_struct *tty, struct ktermios *termios
* USB probe and disconnect routines.
*/
-/* Little helper: write buffers free */
+/* Little helpers: write/read buffers free */
static void acm_write_buffers_free(struct acm *acm)
{
int i;
@@ -777,6 +849,15 @@ 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;
+
+ for (i = 0; i < n; i++)
+ usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
+}
+
/* Little helper: write buffers allocate */
static int acm_write_buffers_alloc(struct acm *acm)
{
@@ -987,6 +1068,7 @@ skip_normal_probe:
acm->urb_task.func = acm_rx_tasklet;
acm->urb_task.data = (unsigned long) acm;
INIT_WORK(&acm->work, acm_softint);
+ INIT_WORK(&acm->waker, acm_waker);
spin_lock_init(&acm->throttle_lock);
spin_lock_init(&acm->write_lock);
spin_lock_init(&acm->read_lock);
@@ -1098,8 +1180,7 @@ alloc_fail8:
for (i = 0; i < ACM_NW; i++)
usb_free_urb(acm->wb[i].urb);
alloc_fail7:
- for (i = 0; i < num_rx_buf; i++)
- usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
+ acm_read_buffers_free(acm);
for (i = 0; i < num_rx_buf; i++)
usb_free_urb(acm->ru[i].urb);
usb_free_urb(acm->ctrlurb);
@@ -1116,6 +1197,7 @@ alloc_fail:
static void stop_data_traffic(struct acm *acm)
{
int i;
+ dbg("Entering stop_data_traffic");
tasklet_disable(&acm->urb_task);
@@ -1128,21 +1210,16 @@ static void stop_data_traffic(struct acm *acm)
tasklet_enable(&acm->urb_task);
cancel_work_sync(&acm->work);
+ cancel_work_sync(&acm->waker);
}
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;
- }
mutex_lock(&open_mutex);
- if (!usb_get_intfdata(intf)) {
+ if (!acm || !acm->dev) {
mutex_unlock(&open_mutex);
return;
}
@@ -1161,10 +1238,10 @@ static void acm_disconnect(struct usb_interface *intf)
acm_write_buffers_free(acm);
usb_buffer_free(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
- for (i = 0; i < acm->rx_buflimit; i++)
- usb_buffer_free(usb_dev, acm->readsize, acm->rb[i].base, acm->rb[i].dma);
+ acm_read_buffers_free(acm);
- usb_driver_release_interface(&acm_driver, intf == acm->control ? acm->data : intf);
+ usb_driver_release_interface(&acm_driver, intf == acm->control ?
+ acm->data : acm->control);
if (!acm->used) {
acm_tty_unregister(acm);
@@ -1178,11 +1255,31 @@ static void acm_disconnect(struct usb_interface *intf)
tty_hangup(acm->tty);
}
+#ifdef CONFIG_PM
static int acm_suspend(struct usb_interface *intf, pm_message_t message)
{
struct acm *acm = usb_get_intfdata(intf);
+ int cnt;
+
+ if (acm->dev->auto_pm) {
+ 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);
+ if (b)
+ return -EBUSY;
+ }
+
+ spin_lock_irq(&acm->read_lock);
+ spin_lock(&acm->write_lock);
+ cnt = acm->susp_count++;
+ spin_unlock(&acm->write_lock);
+ spin_unlock_irq(&acm->read_lock);
- if (acm->susp_count++)
+ if (cnt)
return 0;
/*
we treat opened interfaces differently,
@@ -1201,15 +1298,21 @@ static int acm_resume(struct usb_interface *intf)
{
struct acm *acm = usb_get_intfdata(intf);
int rv = 0;
+ int cnt;
+
+ spin_lock_irq(&acm->read_lock);
+ acm->susp_count -= 1;
+ cnt = acm->susp_count;
+ spin_unlock_irq(&acm->read_lock);
- if (--acm->susp_count)
+ if (cnt)
return 0;
mutex_lock(&acm->mutex);
if (acm->used) {
rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
if (rv < 0)
- goto err_out;
+ goto err_out;
tasklet_schedule(&acm->urb_task);
}
@@ -1218,6 +1321,8 @@ err_out:
mutex_unlock(&acm->mutex);
return rv;
}
+
+#endif /* CONFIG_PM */
/*
* USB driver structure.
*/
@@ -1273,10 +1378,14 @@ static struct usb_driver acm_driver = {
.name = "cdc_acm",
.probe = acm_probe,
.disconnect = acm_disconnect,
+#ifdef CONFIG_PM
.suspend = acm_suspend,
.resume = acm_resume,
+#endif
.id_table = acm_ids,
+#ifdef CONFIG_PM
.supports_autosuspend = 1,
+#endif
};
/*