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authorIngo Molnar <mingo@elte.hu>2010-07-05 08:30:55 +0200
committerIngo Molnar <mingo@elte.hu>2010-07-05 08:30:58 +0200
commit08f8ba07998ab1b9efcdd3f28dadf6866a605ddb (patch)
tree8e09855446f7b0312bb729d4b539090756e57927 /drivers/usb/gadget
parent0879b100f3c187257729f36cba33d96ec2875766 (diff)
parent815c4163b6c8ebf8152f42b0a5fd015cfdcedc78 (diff)
Merge commit 'v2.6.35-rc4' into perf/core
Merge reason: Pick up the latest perf fixes Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/usb/gadget')
-rw-r--r--drivers/usb/gadget/f_eem.c3
-rw-r--r--drivers/usb/gadget/f_mass_storage.c194
-rw-r--r--drivers/usb/gadget/g_ffs.c11
-rw-r--r--drivers/usb/gadget/printer.c32
-rw-r--r--drivers/usb/gadget/s3c2410_udc.c6
-rw-r--r--drivers/usb/gadget/u_serial.c16
6 files changed, 109 insertions, 153 deletions
diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c
index 38226e9a371..95dd4662d6a 100644
--- a/drivers/usb/gadget/f_eem.c
+++ b/drivers/usb/gadget/f_eem.c
@@ -469,8 +469,7 @@ static int eem_unwrap(struct gether *port,
crc = get_unaligned_le32(skb->data + len
- ETH_FCS_LEN);
crc2 = ~crc32_le(~0,
- skb->data,
- skb->len - ETH_FCS_LEN);
+ skb->data, len - ETH_FCS_LEN);
} else {
crc = get_unaligned_be32(skb->data + len
- ETH_FCS_LEN);
diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index 7d05a0be5c6..4ce899c9b16 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -321,8 +321,8 @@ struct fsg_dev;
/* Data shared by all the FSG instances. */
struct fsg_common {
struct usb_gadget *gadget;
- struct fsg_dev *fsg;
- struct fsg_dev *prev_fsg;
+ struct fsg_dev *fsg, *new_fsg;
+ wait_queue_head_t fsg_wait;
/* filesem protects: backing files in use */
struct rw_semaphore filesem;
@@ -351,7 +351,6 @@ struct fsg_common {
enum fsg_state state; /* For exception handling */
unsigned int exception_req_tag;
- u8 config, new_config;
enum data_direction data_dir;
u32 data_size;
u32 data_size_from_cmnd;
@@ -595,7 +594,7 @@ static int fsg_setup(struct usb_function *f,
u16 w_value = le16_to_cpu(ctrl->wValue);
u16 w_length = le16_to_cpu(ctrl->wLength);
- if (!fsg->common->config)
+ if (!fsg_is_set(fsg->common))
return -EOPNOTSUPP;
switch (ctrl->bRequest) {
@@ -2303,24 +2302,20 @@ static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
return -ENOMEM;
}
-/*
- * Reset interface setting and re-init endpoint state (toggle etc).
- * Call with altsetting < 0 to disable the interface. The only other
- * available altsetting is 0, which enables the interface.
- */
-static int do_set_interface(struct fsg_common *common, int altsetting)
+/* Reset interface setting and re-init endpoint state (toggle etc). */
+static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
{
- int rc = 0;
- int i;
- const struct usb_endpoint_descriptor *d;
+ const struct usb_endpoint_descriptor *d;
+ struct fsg_dev *fsg;
+ int i, rc = 0;
if (common->running)
DBG(common, "reset interface\n");
reset:
/* Deallocate the requests */
- if (common->prev_fsg) {
- struct fsg_dev *fsg = common->prev_fsg;
+ if (common->fsg) {
+ fsg = common->fsg;
for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
struct fsg_buffhd *bh = &common->buffhds[i];
@@ -2345,88 +2340,53 @@ reset:
fsg->bulk_out_enabled = 0;
}
- common->prev_fsg = 0;
+ common->fsg = NULL;
+ wake_up(&common->fsg_wait);
}
common->running = 0;
- if (altsetting < 0 || rc != 0)
+ if (!new_fsg || rc)
return rc;
- DBG(common, "set interface %d\n", altsetting);
+ common->fsg = new_fsg;
+ fsg = common->fsg;
- if (fsg_is_set(common)) {
- struct fsg_dev *fsg = common->fsg;
- common->prev_fsg = common->fsg;
+ /* Enable the endpoints */
+ d = fsg_ep_desc(common->gadget,
+ &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
+ rc = enable_endpoint(common, fsg->bulk_in, d);
+ if (rc)
+ goto reset;
+ fsg->bulk_in_enabled = 1;
+
+ d = fsg_ep_desc(common->gadget,
+ &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
+ rc = enable_endpoint(common, fsg->bulk_out, d);
+ if (rc)
+ goto reset;
+ fsg->bulk_out_enabled = 1;
+ common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
+ clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
- /* Enable the endpoints */
- d = fsg_ep_desc(common->gadget,
- &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
- rc = enable_endpoint(common, fsg->bulk_in, d);
+ /* Allocate the requests */
+ for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
+ struct fsg_buffhd *bh = &common->buffhds[i];
+
+ rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
if (rc)
goto reset;
- fsg->bulk_in_enabled = 1;
-
- d = fsg_ep_desc(common->gadget,
- &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
- rc = enable_endpoint(common, fsg->bulk_out, d);
+ rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
if (rc)
goto reset;
- fsg->bulk_out_enabled = 1;
- common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
- clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-
- /* Allocate the requests */
- for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
- struct fsg_buffhd *bh = &common->buffhds[i];
-
- rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
- if (rc)
- goto reset;
- rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
- if (rc)
- goto reset;
- bh->inreq->buf = bh->outreq->buf = bh->buf;
- bh->inreq->context = bh->outreq->context = bh;
- bh->inreq->complete = bulk_in_complete;
- bh->outreq->complete = bulk_out_complete;
- }
-
- common->running = 1;
- for (i = 0; i < common->nluns; ++i)
- common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
- return rc;
- } else {
- return -EIO;
- }
-}
-
-
-/*
- * Change our operational configuration. This code must agree with the code
- * that returns config descriptors, and with interface altsetting code.
- *
- * It's also responsible for power management interactions. Some
- * configurations might not work with our current power sources.
- * For now we just assume the gadget is always self-powered.
- */
-static int do_set_config(struct fsg_common *common, u8 new_config)
-{
- int rc = 0;
-
- /* Disable the single interface */
- if (common->config != 0) {
- DBG(common, "reset config\n");
- common->config = 0;
- rc = do_set_interface(common, -1);
+ bh->inreq->buf = bh->outreq->buf = bh->buf;
+ bh->inreq->context = bh->outreq->context = bh;
+ bh->inreq->complete = bulk_in_complete;
+ bh->outreq->complete = bulk_out_complete;
}
- /* Enable the interface */
- if (new_config != 0) {
- common->config = new_config;
- rc = do_set_interface(common, 0);
- if (rc != 0)
- common->config = 0; /* Reset on errors */
- }
+ common->running = 1;
+ for (i = 0; i < common->nluns; ++i)
+ common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
return rc;
}
@@ -2437,9 +2397,7 @@ static int do_set_config(struct fsg_common *common, u8 new_config)
static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
struct fsg_dev *fsg = fsg_from_func(f);
- fsg->common->prev_fsg = fsg->common->fsg;
- fsg->common->fsg = fsg;
- fsg->common->new_config = 1;
+ fsg->common->new_fsg = fsg;
raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
return 0;
}
@@ -2447,9 +2405,7 @@ static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
static void fsg_disable(struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
- fsg->common->prev_fsg = fsg->common->fsg;
- fsg->common->fsg = fsg;
- fsg->common->new_config = 0;
+ fsg->common->new_fsg = NULL;
raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
}
@@ -2459,19 +2415,17 @@ static void fsg_disable(struct usb_function *f)
static void handle_exception(struct fsg_common *common)
{
siginfo_t info;
- int sig;
int i;
struct fsg_buffhd *bh;
enum fsg_state old_state;
- u8 new_config;
struct fsg_lun *curlun;
unsigned int exception_req_tag;
- int rc;
/* Clear the existing signals. Anything but SIGUSR1 is converted
* into a high-priority EXIT exception. */
for (;;) {
- sig = dequeue_signal_lock(current, &current->blocked, &info);
+ int sig =
+ dequeue_signal_lock(current, &current->blocked, &info);
if (!sig)
break;
if (sig != SIGUSR1) {
@@ -2482,7 +2436,7 @@ static void handle_exception(struct fsg_common *common)
}
/* Cancel all the pending transfers */
- if (fsg_is_set(common)) {
+ if (likely(common->fsg)) {
for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
bh = &common->buffhds[i];
if (bh->inreq_busy)
@@ -2523,7 +2477,6 @@ static void handle_exception(struct fsg_common *common)
common->next_buffhd_to_fill = &common->buffhds[0];
common->next_buffhd_to_drain = &common->buffhds[0];
exception_req_tag = common->exception_req_tag;
- new_config = common->new_config;
old_state = common->state;
if (old_state == FSG_STATE_ABORT_BULK_OUT)
@@ -2573,12 +2526,12 @@ static void handle_exception(struct fsg_common *common)
break;
case FSG_STATE_CONFIG_CHANGE:
- rc = do_set_config(common, new_config);
+ do_set_interface(common, common->new_fsg);
break;
case FSG_STATE_EXIT:
case FSG_STATE_TERMINATED:
- do_set_config(common, 0); /* Free resources */
+ do_set_interface(common, NULL); /* Free resources */
spin_lock_irq(&common->lock);
common->state = FSG_STATE_TERMINATED; /* Stop the thread */
spin_unlock_irq(&common->lock);
@@ -2863,6 +2816,7 @@ buffhds_first_it:
goto error_release;
}
init_completion(&common->thread_notifier);
+ init_waitqueue_head(&common->fsg_wait);
#undef OR
@@ -2957,9 +2911,17 @@ static void fsg_common_release(struct kref *ref)
static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
+ struct fsg_common *common = fsg->common;
DBG(fsg, "unbind\n");
- fsg_common_put(fsg->common);
+ if (fsg->common->fsg == fsg) {
+ fsg->common->new_fsg = NULL;
+ raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
+ /* FIXME: make interruptible or killable somehow? */
+ wait_event(common->fsg_wait, common->fsg != fsg);
+ }
+
+ fsg_common_put(common);
usb_free_descriptors(fsg->function.descriptors);
usb_free_descriptors(fsg->function.hs_descriptors);
kfree(fsg);
@@ -2970,7 +2932,6 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
{
struct fsg_dev *fsg = fsg_from_func(f);
struct usb_gadget *gadget = c->cdev->gadget;
- int rc;
int i;
struct usb_ep *ep;
@@ -2996,6 +2957,11 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
ep->driver_data = fsg->common; /* claim the endpoint */
fsg->bulk_out = ep;
+ /* Copy descriptors */
+ f->descriptors = usb_copy_descriptors(fsg_fs_function);
+ if (unlikely(!f->descriptors))
+ return -ENOMEM;
+
if (gadget_is_dualspeed(gadget)) {
/* Assume endpoint addresses are the same for both speeds */
fsg_hs_bulk_in_desc.bEndpointAddress =
@@ -3003,16 +2969,17 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
fsg_hs_bulk_out_desc.bEndpointAddress =
fsg_fs_bulk_out_desc.bEndpointAddress;
f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
- if (unlikely(!f->hs_descriptors))
+ if (unlikely(!f->hs_descriptors)) {
+ usb_free_descriptors(f->descriptors);
return -ENOMEM;
+ }
}
return 0;
autoconf_fail:
ERROR(fsg, "unable to autoconfigure all endpoints\n");
- rc = -ENOTSUPP;
- return rc;
+ return -ENOTSUPP;
}
@@ -3036,11 +3003,6 @@ static int fsg_add(struct usb_composite_dev *cdev,
fsg->function.name = FSG_DRIVER_DESC;
fsg->function.strings = fsg_strings_array;
- fsg->function.descriptors = usb_copy_descriptors(fsg_fs_function);
- if (unlikely(!fsg->function.descriptors)) {
- rc = -ENOMEM;
- goto error_free_fsg;
- }
fsg->function.bind = fsg_bind;
fsg->function.unbind = fsg_unbind;
fsg->function.setup = fsg_setup;
@@ -3056,19 +3018,9 @@ static int fsg_add(struct usb_composite_dev *cdev,
rc = usb_add_function(c, &fsg->function);
if (unlikely(rc))
- goto error_free_all;
-
- fsg_common_get(fsg->common);
- return 0;
-
-error_free_all:
- usb_free_descriptors(fsg->function.descriptors);
- /* fsg_bind() might have copied those; or maybe not? who cares
- * -- free it just in case. */
- usb_free_descriptors(fsg->function.hs_descriptors);
-error_free_fsg:
- kfree(fsg);
-
+ kfree(fsg);
+ else
+ fsg_common_get(fsg->common);
return rc;
}
diff --git a/drivers/usb/gadget/g_ffs.c b/drivers/usb/gadget/g_ffs.c
index 4b0e4a040d6..d1af253a910 100644
--- a/drivers/usb/gadget/g_ffs.c
+++ b/drivers/usb/gadget/g_ffs.c
@@ -392,6 +392,17 @@ static int __gfs_do_config(struct usb_configuration *c,
if (unlikely(ret < 0))
return ret;
+ /* After previous do_configs there may be some invalid
+ * pointers in c->interface array. This happens every time
+ * a user space function with fewer interfaces than a user
+ * space function that was run before the new one is run. The
+ * compasit's set_config() assumes that if there is no more
+ * then MAX_CONFIG_INTERFACES interfaces in a configuration
+ * then there is a NULL pointer after the last interface in
+ * c->interface array. We need to make sure this is true. */
+ if (c->next_interface_id < ARRAY_SIZE(c->interface))
+ c->interface[c->next_interface_id] = NULL;
+
return 0;
}
diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index 43abf55d8c6..4c3ac5c4223 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -82,7 +82,7 @@ static struct class *usb_gadget_class;
struct printer_dev {
spinlock_t lock; /* lock this structure */
/* lock buffer lists during read/write calls */
- spinlock_t lock_printer_io;
+ struct mutex lock_printer_io;
struct usb_gadget *gadget;
struct usb_request *req; /* for control responses */
u8 config;
@@ -567,7 +567,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
/* We will use this flag later to check if a printer reset happened
@@ -601,7 +601,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
* call or not.
*/
if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -648,7 +648,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
if (dev->reset_printer) {
list_add(&current_rx_req->list, &dev->rx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -673,7 +673,7 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
dev->current_rx_buf = current_rx_buf;
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
@@ -697,7 +697,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
if (len == 0)
return -EINVAL;
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
/* Check if a printer reset happens while we have interrupts on */
@@ -713,7 +713,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
* a NON-Blocking call or not.
*/
if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -752,7 +752,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
if (copy_from_user(req->buf, buf, size)) {
list_add(&req->list, &dev->tx_reqs);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return bytes_copied;
}
@@ -766,14 +766,14 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
if (dev->reset_printer) {
list_add(&req->list, &dev->tx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
list_add(&req->list, &dev->tx_reqs);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
return -EAGAIN;
}
@@ -782,7 +782,7 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
}
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
@@ -820,11 +820,11 @@ printer_poll(struct file *fd, poll_table *wait)
unsigned long flags;
int status = 0;
- spin_lock(&dev->lock_printer_io);
+ mutex_lock(&dev->lock_printer_io);
spin_lock_irqsave(&dev->lock, flags);
setup_rx_reqs(dev);
spin_unlock_irqrestore(&dev->lock, flags);
- spin_unlock(&dev->lock_printer_io);
+ mutex_unlock(&dev->lock_printer_io);
poll_wait(fd, &dev->rx_wait, wait);
poll_wait(fd, &dev->tx_wait, wait);
@@ -1461,7 +1461,7 @@ autoconf_fail:
}
spin_lock_init(&dev->lock);
- spin_lock_init(&dev->lock_printer_io);
+ mutex_init(&dev->lock_printer_io);
INIT_LIST_HEAD(&dev->tx_reqs);
INIT_LIST_HEAD(&dev->tx_reqs_active);
INIT_LIST_HEAD(&dev->rx_reqs);
@@ -1594,7 +1594,7 @@ cleanup(void)
{
int status;
- spin_lock(&usb_printer_gadget.lock_printer_io);
+ mutex_lock(&usb_printer_gadget.lock_printer_io);
class_destroy(usb_gadget_class);
unregister_chrdev_region(g_printer_devno, 2);
@@ -1602,6 +1602,6 @@ cleanup(void)
if (status)
ERROR(dev, "usb_gadget_unregister_driver %x\n", status);
- spin_unlock(&usb_printer_gadget.lock_printer_io);
+ mutex_unlock(&usb_printer_gadget.lock_printer_io);
}
module_exit(cleanup);
diff --git a/drivers/usb/gadget/s3c2410_udc.c b/drivers/usb/gadget/s3c2410_udc.c
index d5f4c1d45c9..e724a051bfd 100644
--- a/drivers/usb/gadget/s3c2410_udc.c
+++ b/drivers/usb/gadget/s3c2410_udc.c
@@ -1700,9 +1700,13 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
if (!driver || driver != udc->driver || !driver->unbind)
return -EINVAL;
- dprintk(DEBUG_NORMAL,"usb_gadget_register_driver() '%s'\n",
+ dprintk(DEBUG_NORMAL, "usb_gadget_unregister_driver() '%s'\n",
driver->driver.name);
+ /* report disconnect */
+ if (driver->disconnect)
+ driver->disconnect(&udc->gadget);
+
driver->unbind(&udc->gadget);
device_del(&udc->gadget.dev);
diff --git a/drivers/usb/gadget/u_serial.c b/drivers/usb/gadget/u_serial.c
index 16bdf77f582..3e8dcb5455e 100644
--- a/drivers/usb/gadget/u_serial.c
+++ b/drivers/usb/gadget/u_serial.c
@@ -536,17 +536,11 @@ recycle:
list_move(&req->list, &port->read_pool);
}
- /* Push from tty to ldisc; this is immediate with low_latency, and
- * may trigger callbacks to this driver ... so drop the spinlock.
+ /* Push from tty to ldisc; without low_latency set this is handled by
+ * a workqueue, so we won't get callbacks and can hold port_lock
*/
if (tty && do_push) {
- spin_unlock_irq(&port->port_lock);
tty_flip_buffer_push(tty);
- wake_up_interruptible(&tty->read_wait);
- spin_lock_irq(&port->port_lock);
-
- /* tty may have been closed */
- tty = port->port_tty;
}
@@ -784,11 +778,6 @@ static int gs_open(struct tty_struct *tty, struct file *file)
port->open_count = 1;
port->openclose = false;
- /* low_latency means ldiscs work in tasklet context, without
- * needing a workqueue schedule ... easier to keep up.
- */
- tty->low_latency = 1;
-
/* if connected, start the I/O stream */
if (port->port_usb) {
struct gserial *gser = port->port_usb;
@@ -1195,6 +1184,7 @@ void gserial_cleanup(void)
n_ports = 0;
tty_unregister_driver(gs_tty_driver);
+ put_tty_driver(gs_tty_driver);
gs_tty_driver = NULL;
pr_debug("%s: cleaned up ttyGS* support\n", __func__);