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authorOliver Neukum <oliver@neukum.org>2007-10-12 19:24:28 +0400
committerGreg Kroah-Hartman <gregkh@suse.de>2008-02-02 01:34:47 +0300
commit1365baf7249bb2d05e774e7681237b8e86f5007a (patch)
treed9a77d461a6cacf1154c59468f47db854982f254 /drivers/usb/class
parenteedffd12e07d8fd150618d603d010b491dc90354 (diff)
downloadlinux-1365baf7249bb2d05e774e7681237b8e86f5007a.tar.xz
USB: autosuspend for cdc-acm
Here we go. This patch implements suspend/resume and autosuspend for the CDC ACM driver. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/class')
-rw-r--r--drivers/usb/class/cdc-acm.c92
-rw-r--r--drivers/usb/class/cdc-acm.h2
2 files changed, 79 insertions, 15 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 912d97aaf9bf..b0f9873ce6b7 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -496,10 +496,19 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
otherwise it is scheduled, and with high data rates data can get lost. */
tty->low_latency = 1;
+ if (usb_autopm_get_interface(acm->control)) {
+ mutex_unlock(&open_mutex);
+ return -EIO;
+ }
+
+ mutex_lock(&acm->mutex);
+ mutex_unlock(&open_mutex);
if (acm->used++) {
+ usb_autopm_put_interface(acm->control);
goto done;
}
+
acm->ctrlurb->dev = acm->dev;
if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
dbg("usb_submit_urb(ctrl irq) failed");
@@ -526,14 +535,15 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
done:
err_out:
- mutex_unlock(&open_mutex);
+ mutex_unlock(&acm->mutex);
return rv;
full_bailout:
usb_kill_urb(acm->ctrlurb);
bail_out:
+ usb_autopm_put_interface(acm->control);
acm->used--;
- mutex_unlock(&open_mutex);
+ mutex_unlock(&acm->mutex);
return -EIO;
}
@@ -570,6 +580,7 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp)
usb_kill_urb(acm->writeurb);
for (i = 0; i < nr; i++)
usb_kill_urb(acm->ru[i].urb);
+ usb_autopm_put_interface(acm->control);
} else
acm_tty_unregister(acm);
}
@@ -980,6 +991,7 @@ skip_normal_probe:
spin_lock_init(&acm->throttle_lock);
spin_lock_init(&acm->write_lock);
spin_lock_init(&acm->read_lock);
+ mutex_init(&acm->mutex);
acm->write_ready = 1;
acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
@@ -1096,6 +1108,25 @@ alloc_fail:
return -ENOMEM;
}
+static void stop_data_traffic(struct acm *acm)
+{
+ int i;
+
+ tasklet_disable(&acm->urb_task);
+
+ usb_kill_urb(acm->ctrlurb);
+ usb_kill_urb(acm->writeurb);
+ for (i = 0; i < acm->rx_buflimit; 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);
+
+ cancel_work_sync(&acm->work);
+}
+
static void acm_disconnect(struct usb_interface *intf)
{
struct acm *acm = usb_get_intfdata(intf);
@@ -1123,19 +1154,7 @@ static void acm_disconnect(struct usb_interface *intf)
usb_set_intfdata(acm->control, NULL);
usb_set_intfdata(acm->data, NULL);
- tasklet_disable(&acm->urb_task);
-
- usb_kill_urb(acm->ctrlurb);
- usb_kill_urb(acm->writeurb);
- for (i = 0; i < acm->rx_buflimit; 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 */
+ stop_data_traffic(acm);
acm_write_buffers_free(acm);
usb_buffer_free(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
@@ -1156,6 +1175,46 @@ static void acm_disconnect(struct usb_interface *intf)
tty_hangup(acm->tty);
}
+static int acm_suspend(struct usb_interface *intf, pm_message_t message)
+{
+ struct acm *acm = usb_get_intfdata(intf);
+
+ if (acm->susp_count++)
+ return 0;
+ /*
+ we treat opened interfaces differently,
+ we must guard against open
+ */
+ mutex_lock(&acm->mutex);
+
+ if (acm->used)
+ stop_data_traffic(acm);
+
+ mutex_unlock(&acm->mutex);
+ return 0;
+}
+
+static int acm_resume(struct usb_interface *intf)
+{
+ struct acm *acm = usb_get_intfdata(intf);
+ int rv = 0;
+
+ if (--acm->susp_count)
+ return 0;
+
+ mutex_lock(&acm->mutex);
+ if (acm->used) {
+ rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
+ if (rv < 0)
+ goto err_out;
+
+ tasklet_schedule(&acm->urb_task);
+ }
+
+err_out:
+ mutex_unlock(&acm->mutex);
+ return rv;
+}
/*
* USB driver structure.
*/
@@ -1208,7 +1267,10 @@ static struct usb_driver acm_driver = {
.name = "cdc_acm",
.probe = acm_probe,
.disconnect = acm_disconnect,
+ .suspend = acm_suspend,
+ .resume = acm_resume,
.id_table = acm_ids,
+ .supports_autosuspend = 1,
};
/*
diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h
index 09f7765dbf8d..8df6a57dcf9e 100644
--- a/drivers/usb/class/cdc-acm.h
+++ b/drivers/usb/class/cdc-acm.h
@@ -107,6 +107,7 @@ struct acm {
int write_used; /* number of non-empty write buffers */
int write_ready; /* write urb is not running */
spinlock_t write_lock;
+ struct mutex mutex;
struct usb_cdc_line_coding line; /* bits, stop, parity */
struct work_struct work; /* work queue entry for line discipline waking up */
struct tasklet_struct urb_task; /* rx processing */
@@ -120,6 +121,7 @@ struct acm {
unsigned char throttle; /* throttled by tty layer */
unsigned char clocal; /* termios CLOCAL */
unsigned int ctrl_caps; /* control capabilities from the class specific header */
+ unsigned int susp_count; /* number of suspended interfaces */
};
#define CDC_DATA_INTERFACE_TYPE 0x0a