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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.c338
1 files changed, 192 insertions, 146 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index a8078d0638f..9543b19d410 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -58,12 +58,62 @@ static struct usb_driver acm_driver;
static struct tty_driver *acm_tty_driver;
static struct acm *acm_table[ACM_TTY_MINORS];
-static DEFINE_MUTEX(open_mutex);
+static DEFINE_MUTEX(acm_table_lock);
-#define ACM_READY(acm) (acm && acm->dev && acm->port.count)
+/*
+ * acm_table accessors
+ */
-static const struct tty_port_operations acm_port_ops = {
-};
+/*
+ * Look up an ACM structure by index. If found and not disconnected, increment
+ * its refcount and return it with its mutex held.
+ */
+static struct acm *acm_get_by_index(unsigned index)
+{
+ struct acm *acm;
+
+ mutex_lock(&acm_table_lock);
+ acm = acm_table[index];
+ if (acm) {
+ mutex_lock(&acm->mutex);
+ if (acm->disconnected) {
+ mutex_unlock(&acm->mutex);
+ acm = NULL;
+ } else {
+ tty_port_get(&acm->port);
+ mutex_unlock(&acm->mutex);
+ }
+ }
+ mutex_unlock(&acm_table_lock);
+ return acm;
+}
+
+/*
+ * Try to find an available minor number and if found, associate it with 'acm'.
+ */
+static int acm_alloc_minor(struct acm *acm)
+{
+ int minor;
+
+ mutex_lock(&acm_table_lock);
+ for (minor = 0; minor < ACM_TTY_MINORS; minor++) {
+ if (!acm_table[minor]) {
+ acm_table[minor] = acm;
+ break;
+ }
+ }
+ mutex_unlock(&acm_table_lock);
+
+ return minor;
+}
+
+/* Release the minor number associated with 'acm'. */
+static void acm_release_minor(struct acm *acm)
+{
+ mutex_lock(&acm_table_lock);
+ acm_table[acm->minor] = NULL;
+ mutex_unlock(&acm_table_lock);
+}
/*
* Functions for ACM control messages.
@@ -267,9 +317,6 @@ static void acm_ctrl_irq(struct urb *urb)
goto exit;
}
- if (!ACM_READY(acm))
- goto exit;
-
usb_mark_last_busy(acm->dev);
data = (unsigned char *)(dr + 1);
@@ -429,8 +476,7 @@ static void acm_write_bulk(struct urb *urb)
spin_lock_irqsave(&acm->write_lock, flags);
acm_write_done(acm, wb);
spin_unlock_irqrestore(&acm->write_lock, flags);
- if (ACM_READY(acm))
- schedule_work(&acm->work);
+ schedule_work(&acm->work);
}
static void acm_softint(struct work_struct *work)
@@ -440,8 +486,6 @@ static void acm_softint(struct work_struct *work)
dev_vdbg(&acm->data->dev, "%s\n", __func__);
- if (!ACM_READY(acm))
- return;
tty = tty_port_tty_get(&acm->port);
if (!tty)
return;
@@ -453,93 +497,122 @@ static void acm_softint(struct work_struct *work)
* TTY handlers
*/
-static int acm_tty_open(struct tty_struct *tty, struct file *filp)
+static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct acm *acm;
- int rv = -ENODEV;
-
- mutex_lock(&open_mutex);
+ int retval;
- acm = acm_table[tty->index];
- if (!acm || !acm->dev)
- goto out;
- else
- rv = 0;
+ dev_dbg(tty->dev, "%s\n", __func__);
- dev_dbg(&acm->control->dev, "%s\n", __func__);
+ acm = acm_get_by_index(tty->index);
+ if (!acm)
+ return -ENODEV;
- set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
+ retval = tty_init_termios(tty);
+ if (retval)
+ goto error_init_termios;
tty->driver_data = acm;
- tty_port_tty_set(&acm->port, tty);
- if (usb_autopm_get_interface(acm->control) < 0)
- goto early_bail;
- else
- acm->control->needs_remote_wakeup = 1;
+ /* Final install (we use the default method) */
+ tty_driver_kref_get(driver);
+ tty->count++;
+ driver->ttys[tty->index] = tty;
+
+ return 0;
+
+error_init_termios:
+ tty_port_put(&acm->port);
+ return retval;
+}
+
+static int acm_tty_open(struct tty_struct *tty, struct file *filp)
+{
+ struct acm *acm = tty->driver_data;
+
+ dev_dbg(tty->dev, "%s\n", __func__);
+
+ return tty_port_open(&acm->port, tty, filp);
+}
+
+static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
+{
+ struct acm *acm = container_of(port, struct acm, port);
+ int retval = -ENODEV;
+
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
mutex_lock(&acm->mutex);
- if (acm->port.count++) {
- mutex_unlock(&acm->mutex);
- usb_autopm_put_interface(acm->control);
- goto out;
- }
+ if (acm->disconnected)
+ goto disconnected;
+
+ retval = usb_autopm_get_interface(acm->control);
+ if (retval)
+ goto error_get_interface;
+
+ /*
+ * FIXME: Why do we need this? Allocating 64K of physically contiguous
+ * memory is really nasty...
+ */
+ set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
+ acm->control->needs_remote_wakeup = 1;
acm->ctrlurb->dev = acm->dev;
if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
dev_err(&acm->control->dev,
"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
- goto bail_out;
+ goto error_submit_urb;
}
- if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) &&
+ acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS;
+ if (acm_set_control(acm, acm->ctrlout) < 0 &&
(acm->ctrl_caps & USB_CDC_CAP_LINE))
- goto bail_out;
+ goto error_set_control;
usb_autopm_put_interface(acm->control);
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);
+ goto error_submit_read_urbs;
mutex_unlock(&acm->mutex);
-out:
- mutex_unlock(&open_mutex);
- return rv;
-bail_out:
- acm->port.count--;
- mutex_unlock(&acm->mutex);
+ return 0;
+
+error_submit_read_urbs:
+ acm->ctrlout = 0;
+ acm_set_control(acm, acm->ctrlout);
+error_set_control:
+ usb_kill_urb(acm->ctrlurb);
+error_submit_urb:
usb_autopm_put_interface(acm->control);
-early_bail:
- mutex_unlock(&open_mutex);
- tty_port_tty_set(&acm->port, NULL);
- return -EIO;
+error_get_interface:
+disconnected:
+ mutex_unlock(&acm->mutex);
+ return retval;
}
-static void acm_tty_unregister(struct acm *acm)
+static void acm_port_destruct(struct tty_port *port)
{
- int i;
+ struct acm *acm = container_of(port, struct acm, port);
+
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
tty_unregister_device(acm_tty_driver, acm->minor);
+ acm_release_minor(acm);
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 < acm->rx_buflimit; i++)
- usb_free_urb(acm->read_urbs[i]);
kfree(acm->country_codes);
kfree(acm);
}
-static void acm_port_down(struct acm *acm)
+static void acm_port_shutdown(struct tty_port *port)
{
+ struct acm *acm = container_of(port, struct acm, port);
int i;
- if (acm->dev) {
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
+
+ mutex_lock(&acm->mutex);
+ if (!acm->disconnected) {
usb_autopm_get_interface(acm->control);
acm_set_control(acm, acm->ctrlout = 0);
usb_kill_urb(acm->ctrlurb);
@@ -550,40 +623,28 @@ static void acm_port_down(struct acm *acm)
acm->control->needs_remote_wakeup = 0;
usb_autopm_put_interface(acm->control);
}
+ mutex_unlock(&acm->mutex);
+}
+
+static void acm_tty_cleanup(struct tty_struct *tty)
+{
+ struct acm *acm = tty->driver_data;
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
+ tty_port_put(&acm->port);
}
static void acm_tty_hangup(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
tty_port_hangup(&acm->port);
- mutex_lock(&open_mutex);
- acm_port_down(acm);
- mutex_unlock(&open_mutex);
}
static void acm_tty_close(struct tty_struct *tty, struct file *filp)
{
struct acm *acm = tty->driver_data;
-
- /* Perform the closing process and see if we need to do the hardware
- shutdown */
- if (!acm)
- return;
-
- mutex_lock(&open_mutex);
- if (tty_port_close_start(&acm->port, tty, filp) == 0) {
- if (!acm->dev) {
- tty_port_tty_set(&acm->port, NULL);
- acm_tty_unregister(acm);
- tty->driver_data = NULL;
- }
- mutex_unlock(&open_mutex);
- return;
- }
- acm_port_down(acm);
- tty_port_close_end(&acm->port, tty);
- tty_port_tty_set(&acm->port, NULL);
- mutex_unlock(&open_mutex);
+ dev_dbg(&acm->control->dev, "%s\n", __func__);
+ tty_port_close(&acm->port, tty, filp);
}
static int acm_tty_write(struct tty_struct *tty,
@@ -595,8 +656,6 @@ static int acm_tty_write(struct tty_struct *tty,
int wbn;
struct acm_wb *wb;
- if (!ACM_READY(acm))
- return -EINVAL;
if (!count)
return 0;
@@ -625,8 +684,6 @@ static int acm_tty_write(struct tty_struct *tty,
static int acm_tty_write_room(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
- if (!ACM_READY(acm))
- return -EINVAL;
/*
* Do not let the line discipline to know that we have a reserve,
* or it might get too enthusiastic.
@@ -637,7 +694,11 @@ static int acm_tty_write_room(struct tty_struct *tty)
static int acm_tty_chars_in_buffer(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
- if (!ACM_READY(acm))
+ /*
+ * if the device was unplugged then any remaining characters fell out
+ * of the connector ;)
+ */
+ if (acm->disconnected)
return 0;
/*
* This is inaccurate (overcounts), but it works.
@@ -649,9 +710,6 @@ static void acm_tty_throttle(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
- if (!ACM_READY(acm))
- return;
-
spin_lock_irq(&acm->read_lock);
acm->throttle_req = 1;
spin_unlock_irq(&acm->read_lock);
@@ -662,9 +720,6 @@ 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_irq(&acm->read_lock);
was_throttled = acm->throttled;
acm->throttled = 0;
@@ -679,8 +734,7 @@ static int acm_tty_break_ctl(struct tty_struct *tty, int state)
{
struct acm *acm = tty->driver_data;
int retval;
- if (!ACM_READY(acm))
- return -EINVAL;
+
retval = acm_send_break(acm, state ? 0xffff : 0);
if (retval < 0)
dev_dbg(&acm->control->dev, "%s - send break failed\n",
@@ -692,9 +746,6 @@ static int acm_tty_tiocmget(struct tty_struct *tty)
{
struct acm *acm = tty->driver_data;
- if (!ACM_READY(acm))
- return -EINVAL;
-
return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
(acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
(acm->ctrlin & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
@@ -709,9 +760,6 @@ static int acm_tty_tiocmset(struct tty_struct *tty,
struct acm *acm = tty->driver_data;
unsigned int newctrl;
- if (!ACM_READY(acm))
- return -EINVAL;
-
newctrl = acm->ctrlout;
set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
(set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
@@ -728,11 +776,6 @@ static int acm_tty_tiocmset(struct tty_struct *tty,
static int acm_tty_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
- struct acm *acm = tty->driver_data;
-
- if (!ACM_READY(acm))
- return -EINVAL;
-
return -ENOIOCTLCMD;
}
@@ -756,9 +799,6 @@ static void acm_tty_set_termios(struct tty_struct *tty,
struct usb_cdc_line_coding newline;
int newctrl = acm->ctrlout;
- if (!ACM_READY(acm))
- return;
-
newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
newline.bParityType = termios->c_cflag & PARENB ?
@@ -788,6 +828,12 @@ static void acm_tty_set_termios(struct tty_struct *tty,
}
}
+static const struct tty_port_operations acm_port_ops = {
+ .shutdown = acm_port_shutdown,
+ .activate = acm_port_activate,
+ .destruct = acm_port_destruct,
+};
+
/*
* USB probe and disconnect routines.
*/
@@ -1047,12 +1093,6 @@ skip_normal_probe:
}
made_compressed_probe:
dev_dbg(&intf->dev, "interfaces are valid\n");
- for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
-
- if (minor == ACM_TTY_MINORS) {
- dev_err(&intf->dev, "no more free acm devices\n");
- return -ENODEV;
- }
acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
if (acm == NULL) {
@@ -1060,6 +1100,13 @@ made_compressed_probe:
goto alloc_fail;
}
+ minor = acm_alloc_minor(acm);
+ if (minor == ACM_TTY_MINORS) {
+ dev_err(&intf->dev, "no more free acm devices\n");
+ kfree(acm);
+ return -ENODEV;
+ }
+
ctrlsize = usb_endpoint_maxp(epctrl);
readsize = usb_endpoint_maxp(epread) *
(quirks == SINGLE_RX_URB ? 1 : 2);
@@ -1183,6 +1230,8 @@ made_compressed_probe:
i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
if (i < 0) {
kfree(acm->country_codes);
+ acm->country_codes = NULL;
+ acm->country_code_size = 0;
goto skip_countries;
}
@@ -1191,6 +1240,8 @@ made_compressed_probe:
if (i < 0) {
device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
kfree(acm->country_codes);
+ acm->country_codes = NULL;
+ acm->country_code_size = 0;
goto skip_countries;
}
}
@@ -1218,8 +1269,6 @@ skip_countries:
usb_get_intf(control_interface);
tty_register_device(acm_tty_driver, minor, &control_interface->dev);
- acm_table[minor] = acm;
-
return 0;
alloc_fail7:
for (i = 0; i < ACM_NW; i++)
@@ -1234,6 +1283,7 @@ alloc_fail5:
alloc_fail4:
usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
alloc_fail2:
+ acm_release_minor(acm);
kfree(acm);
alloc_fail:
return -ENOMEM;
@@ -1259,12 +1309,16 @@ static void acm_disconnect(struct usb_interface *intf)
struct acm *acm = usb_get_intfdata(intf);
struct usb_device *usb_dev = interface_to_usbdev(intf);
struct tty_struct *tty;
+ int i;
+
+ dev_dbg(&intf->dev, "%s\n", __func__);
/* sibling interface is already cleaning up */
if (!acm)
return;
- mutex_lock(&open_mutex);
+ mutex_lock(&acm->mutex);
+ acm->disconnected = true;
if (acm->country_codes) {
device_remove_file(&acm->control->dev,
&dev_attr_wCountryCodes);
@@ -1272,33 +1326,32 @@ static void acm_disconnect(struct usb_interface *intf)
&dev_attr_iCountryCodeRelDate);
}
device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
- acm->dev = NULL;
usb_set_intfdata(acm->control, NULL);
usb_set_intfdata(acm->data, NULL);
+ mutex_unlock(&acm->mutex);
+
+ tty = tty_port_tty_get(&acm->port);
+ if (tty) {
+ tty_vhangup(tty);
+ tty_kref_put(tty);
+ }
stop_data_traffic(acm);
+ usb_free_urb(acm->ctrlurb);
+ for (i = 0; i < ACM_NW; i++)
+ usb_free_urb(acm->wb[i].urb);
+ for (i = 0; i < acm->rx_buflimit; i++)
+ usb_free_urb(acm->read_urbs[i]);
acm_write_buffers_free(acm);
- usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer,
- acm->ctrl_dma);
+ usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
acm_read_buffers_free(acm);
if (!acm->combined_interfaces)
usb_driver_release_interface(&acm_driver, intf == acm->control ?
acm->data : acm->control);
- if (acm->port.count == 0) {
- acm_tty_unregister(acm);
- mutex_unlock(&open_mutex);
- return;
- }
-
- mutex_unlock(&open_mutex);
- tty = tty_port_tty_get(&acm->port);
- if (tty) {
- tty_hangup(tty);
- tty_kref_put(tty);
- }
+ tty_port_put(&acm->port);
}
#ifdef CONFIG_PM
@@ -1325,16 +1378,10 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
if (cnt)
return 0;
- /*
- we treat opened interfaces differently,
- we must guard against open
- */
- mutex_lock(&acm->mutex);
- if (acm->port.count)
+ if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
stop_data_traffic(acm);
- mutex_unlock(&acm->mutex);
return 0;
}
@@ -1353,8 +1400,7 @@ static int acm_resume(struct usb_interface *intf)
if (cnt)
return 0;
- mutex_lock(&acm->mutex);
- if (acm->port.count) {
+ if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
spin_lock_irq(&acm->write_lock);
@@ -1378,7 +1424,6 @@ static int acm_resume(struct usb_interface *intf)
}
err_out:
- mutex_unlock(&acm->mutex);
return rv;
}
@@ -1387,15 +1432,14 @@ static int acm_reset_resume(struct usb_interface *intf)
struct acm *acm = usb_get_intfdata(intf);
struct tty_struct *tty;
- mutex_lock(&acm->mutex);
- if (acm->port.count) {
+ if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
tty = tty_port_tty_get(&acm->port);
if (tty) {
tty_hangup(tty);
tty_kref_put(tty);
}
}
- mutex_unlock(&acm->mutex);
+
return acm_resume(intf);
}
@@ -1604,8 +1648,10 @@ static struct usb_driver acm_driver = {
*/
static const struct tty_operations acm_ops = {
+ .install = acm_tty_install,
.open = acm_tty_open,
.close = acm_tty_close,
+ .cleanup = acm_tty_cleanup,
.hangup = acm_tty_hangup,
.write = acm_tty_write,
.write_room = acm_tty_write_room,