tty: cdc_acm add krefs
Now we have a port structure begin using the fields and kref counts
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 41d4ca5..b4e73aa 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -62,7 +62,7 @@
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/mutex.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <asm/byteorder.h>
@@ -87,7 +87,7 @@
static DEFINE_MUTEX(open_mutex);
-#define ACM_READY(acm) (acm && acm->dev && acm->used)
+#define ACM_READY(acm) (acm && acm->dev && acm->port.count)
static const struct tty_port_operations acm_port_ops = {
};
@@ -265,6 +265,7 @@
{
struct acm *acm = urb->context;
struct usb_cdc_notification *dr = urb->transfer_buffer;
+ struct tty_struct *tty;
unsigned char *data;
int newctrl;
int retval;
@@ -297,12 +298,16 @@
break;
case USB_CDC_NOTIFY_SERIAL_STATE:
-
+ tty = tty_port_tty_get(&acm->port);
newctrl = get_unaligned_le16(data);
- if (acm->tty && !acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
- dbg("calling hangup");
- tty_hangup(acm->tty);
+ if (tty) {
+ if (!acm->clocal &&
+ (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
+ dbg("calling hangup");
+ tty_hangup(tty);
+ }
+ tty_kref_put(tty);
}
acm->ctrlin = newctrl;
@@ -374,15 +379,14 @@
{
struct acm *acm = (void *)_acm;
struct acm_rb *buf;
- struct tty_struct *tty = acm->tty;
+ struct tty_struct *tty;
struct acm_ru *rcv;
unsigned long flags;
unsigned char throttled;
dbg("Entering acm_rx_tasklet");
- if (!ACM_READY(acm))
- {
+ if (!ACM_READY(acm)) {
dbg("acm_rx_tasklet: ACM not ready");
return;
}
@@ -390,12 +394,13 @@
spin_lock_irqsave(&acm->throttle_lock, flags);
throttled = acm->throttle;
spin_unlock_irqrestore(&acm->throttle_lock, flags);
- if (throttled)
- {
+ if (throttled) {
dbg("acm_rx_tasklet: throttled");
return;
}
+ tty = tty_port_tty_get(&acm->port);
+
next_buffer:
spin_lock_irqsave(&acm->read_lock, flags);
if (list_empty(&acm->filled_read_bufs)) {
@@ -409,20 +414,22 @@
dbg("acm_rx_tasklet: procesing buf 0x%p, size = %d", buf, buf->size);
- tty_buffer_request_room(tty, buf->size);
- 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);
-
- if (throttled) {
- 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;
+ if (tty) {
+ spin_lock_irqsave(&acm->throttle_lock, flags);
+ throttled = acm->throttle;
+ spin_unlock_irqrestore(&acm->throttle_lock, flags);
+ if (!throttled) {
+ tty_buffer_request_room(tty, buf->size);
+ 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);
@@ -431,6 +438,8 @@
goto next_buffer;
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)) {
@@ -502,11 +511,14 @@
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");
if (!ACM_READY(acm))
return;
- tty_wakeup(acm->tty);
+ tty = tty_port_tty_get(&acm->port);
+ tty_wakeup(tty);
+ tty_kref_put(tty);
}
static void acm_waker(struct work_struct *waker)
@@ -546,8 +558,9 @@
rv = 0;
set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
+
tty->driver_data = acm;
- acm->tty = tty;
+ tty_port_tty_set(&acm->port, tty);
if (usb_autopm_get_interface(acm->control) < 0)
goto early_bail;
@@ -555,11 +568,10 @@
acm->control->needs_remote_wakeup = 1;
mutex_lock(&acm->mutex);
- if (acm->used++) {
+ if (acm->port.count++) {
usb_autopm_put_interface(acm->control);
goto done;
- }
-
+ }
acm->ctrlurb->dev = acm->dev;
if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
@@ -570,6 +582,7 @@
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);
@@ -585,7 +598,7 @@
acm->throttle = 0;
tasklet_schedule(&acm->urb_task);
-
+ rv = tty_port_block_til_ready(&acm->port, tty, filp);
done:
mutex_unlock(&acm->mutex);
err_out:
@@ -596,16 +609,17 @@
usb_kill_urb(acm->ctrlurb);
bail_out:
usb_autopm_put_interface(acm->control);
- acm->used--;
+ acm->port.count--;
mutex_unlock(&acm->mutex);
early_bail:
mutex_unlock(&open_mutex);
+ tty_port_tty_set(&acm->port, NULL);
return -EIO;
}
static void acm_tty_unregister(struct acm *acm)
{
- int i,nr;
+ int i, nr;
nr = acm->rx_buflimit;
tty_unregister_device(acm_tty_driver, acm->minor);
@@ -622,37 +636,51 @@
static int acm_tty_chars_in_buffer(struct tty_struct *tty);
+static void acm_port_down(struct acm *acm, int drain)
+{
+ int i, nr = acm->rx_buflimit;
+ mutex_lock(&open_mutex);
+ if (acm->dev) {
+ usb_autopm_get_interface(acm->control);
+ acm_set_control(acm, acm->ctrlout = 0);
+ /* try letting the last writes drain naturally */
+ if (drain) {
+ wait_event_interruptible_timeout(acm->drain_wait,
+ (ACM_NW == acm_wb_is_avail(acm)) || !acm->dev,
+ ACM_CLOSE_TIMEOUT * HZ);
+ }
+ 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);
+ }
+ mutex_unlock(&open_mutex);
+}
+
+static void acm_tty_hangup(struct tty_struct *tty)
+{
+ struct acm *acm = tty->driver_data;
+ tty_port_hangup(&acm->port);
+ acm_port_down(acm, 0);
+}
+
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)
+ /* Perform the closing process and see if we need to do the hardware
+ shutdown */
+ if (tty_port_close_start(&acm->port, tty, filp) == 0)
return;
-
- nr = acm->rx_buflimit;
+ acm_port_down(acm, 0);
+ tty_port_close_end(&acm->port, tty);
mutex_lock(&open_mutex);
- if (!--acm->used) {
- if (acm->dev) {
- usb_autopm_get_interface(acm->control);
- acm_set_control(acm, acm->ctrlout = 0);
-
- /* try letting the last writes drain naturally */
- wait_event_interruptible_timeout(acm->drain_wait,
- (ACM_NW == acm_wb_is_avail(acm))
- || !acm->dev,
- ACM_CLOSE_TIMEOUT * HZ);
-
- 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);
- }
+ tty_port_tty_set(&acm->port, NULL);
+ if (!acm->dev)
+ acm_tty_unregister(acm);
mutex_unlock(&open_mutex);
}
@@ -885,8 +913,8 @@
return 0;
}
-static int acm_probe (struct usb_interface *intf,
- const struct usb_device_id *id)
+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;
@@ -1232,6 +1260,7 @@
{
struct acm *acm = usb_get_intfdata(intf);
struct usb_device *usb_dev = interface_to_usbdev(intf);
+ struct tty_struct *tty;
/* sibling interface is already cleaning up */
if (!acm)
@@ -1258,16 +1287,18 @@
usb_driver_release_interface(&acm_driver, intf == acm->control ?
acm->data : acm->control);
- if (!acm->used) {
+ if (acm->port.count == 0) {
acm_tty_unregister(acm);
mutex_unlock(&open_mutex);
return;
}
mutex_unlock(&open_mutex);
-
- if (acm->tty)
- tty_hangup(acm->tty);
+ tty = tty_port_tty_get(&acm->port);
+ if (tty) {
+ tty_hangup(tty);
+ tty_kref_put(tty);
+ }
}
#ifdef CONFIG_PM
@@ -1302,7 +1333,7 @@
*/
mutex_lock(&acm->mutex);
- if (acm->used)
+ if (acm->port.count)
stop_data_traffic(acm);
mutex_unlock(&acm->mutex);
@@ -1324,7 +1355,7 @@
return 0;
mutex_lock(&acm->mutex);
- if (acm->used) {
+ if (acm->port.count) {
rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
if (rv < 0)
goto err_out;
@@ -1434,6 +1465,7 @@
static const struct tty_operations acm_ops = {
.open = acm_tty_open,
.close = acm_tty_close,
+ .hangup = acm_tty_hangup,
.write = acm_tty_write,
.write_room = acm_tty_write_room,
.ioctl = acm_tty_ioctl,