WSL2-Linux-Kernel/drivers/greybus/connection.c

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23 KiB
C
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// SPDX-License-Identifier: GPL-2.0
/*
* Greybus connections
*
* Copyright 2014 Google Inc.
* Copyright 2014 Linaro Ltd.
*/
#include <linux/workqueue.h>
#include <linux/greybus.h>
#include "greybus_trace.h"
#define GB_CONNECTION_CPORT_QUIESCE_TIMEOUT 1000
static void gb_connection_kref_release(struct kref *kref);
static DEFINE_SPINLOCK(gb_connections_lock);
static DEFINE_MUTEX(gb_connection_mutex);
/* Caller holds gb_connection_mutex. */
static bool gb_connection_cport_in_use(struct gb_interface *intf, u16 cport_id)
{
struct gb_host_device *hd = intf->hd;
struct gb_connection *connection;
list_for_each_entry(connection, &hd->connections, hd_links) {
if (connection->intf == intf &&
connection->intf_cport_id == cport_id)
return true;
}
return false;
}
static void gb_connection_get(struct gb_connection *connection)
{
kref_get(&connection->kref);
trace_gb_connection_get(connection);
}
static void gb_connection_put(struct gb_connection *connection)
{
trace_gb_connection_put(connection);
kref_put(&connection->kref, gb_connection_kref_release);
}
/*
* Returns a reference-counted pointer to the connection if found.
*/
static struct gb_connection *
gb_connection_hd_find(struct gb_host_device *hd, u16 cport_id)
{
struct gb_connection *connection;
unsigned long flags;
spin_lock_irqsave(&gb_connections_lock, flags);
list_for_each_entry(connection, &hd->connections, hd_links)
if (connection->hd_cport_id == cport_id) {
gb_connection_get(connection);
goto found;
}
connection = NULL;
found:
spin_unlock_irqrestore(&gb_connections_lock, flags);
return connection;
}
/*
* Callback from the host driver to let us know that data has been
* received on the bundle.
*/
void greybus_data_rcvd(struct gb_host_device *hd, u16 cport_id,
u8 *data, size_t length)
{
struct gb_connection *connection;
trace_gb_hd_in(hd);
connection = gb_connection_hd_find(hd, cport_id);
if (!connection) {
dev_err(&hd->dev,
"nonexistent connection (%zu bytes dropped)\n", length);
return;
}
gb_connection_recv(connection, data, length);
gb_connection_put(connection);
}
EXPORT_SYMBOL_GPL(greybus_data_rcvd);
static void gb_connection_kref_release(struct kref *kref)
{
struct gb_connection *connection;
connection = container_of(kref, struct gb_connection, kref);
trace_gb_connection_release(connection);
kfree(connection);
}
static void gb_connection_init_name(struct gb_connection *connection)
{
u16 hd_cport_id = connection->hd_cport_id;
u16 cport_id = 0;
u8 intf_id = 0;
if (connection->intf) {
intf_id = connection->intf->interface_id;
cport_id = connection->intf_cport_id;
}
snprintf(connection->name, sizeof(connection->name),
"%u/%u:%u", hd_cport_id, intf_id, cport_id);
}
/*
* _gb_connection_create() - create a Greybus connection
* @hd: host device of the connection
* @hd_cport_id: host-device cport id, or -1 for dynamic allocation
* @intf: remote interface, or NULL for static connections
* @bundle: remote-interface bundle (may be NULL)
* @cport_id: remote-interface cport id, or 0 for static connections
* @handler: request handler (may be NULL)
* @flags: connection flags
*
* Create a Greybus connection, representing the bidirectional link
* between a CPort on a (local) Greybus host device and a CPort on
* another Greybus interface.
*
greybus: introduce an operation abstraction This patch defines a new "operation" abstraction. An operation is a request from by one end of a connection to the function (or AP) on the other, coupled with a matching response returned to the requestor. The request indicates some action to be performed by the target of the request (such as "read some data"). Once the action has completed the target sends back an operation response message. Additional data can be supplied by the sender with its request, and/or by the target with its resposne message. Each request message has a unique id, generated by the sender. The sender recognizes the matching response by the presence of this id value. Each end of a connection is responsible for creating unique ids for the requests it sends. An operation also has a type, whose interpretation is dependent on the function type on the end of the connection opposite the sender. It is up to the creator of an operation to fill in the data (if any) to be sent with the request. Note that not all requests are initiated by the AP. Incoming data on a module function can result in a request message being sent from that function to the AP to notify of the data's arrival. Once the AP has processed this, it sends a response to the sender. Every operation response contains a status byte. If it's value is 0, the operation was successful. Any other value indicates an error. Add a defintion of U16_MAX to "kernel_ver.h". Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
2014-10-02 06:54:15 +04:00
* A connection also maintains the state of operations sent over the
* connection.
*
* Serialised against concurrent create and destroy using the
* gb_connection_mutex.
*
* Return: A pointer to the new connection if successful, or an ERR_PTR
* otherwise.
*/
static struct gb_connection *
_gb_connection_create(struct gb_host_device *hd, int hd_cport_id,
struct gb_interface *intf,
struct gb_bundle *bundle, int cport_id,
gb_request_handler_t handler,
unsigned long flags)
{
struct gb_connection *connection;
int ret;
mutex_lock(&gb_connection_mutex);
if (intf && gb_connection_cport_in_use(intf, cport_id)) {
dev_err(&intf->dev, "cport %u already in use\n", cport_id);
ret = -EBUSY;
goto err_unlock;
}
ret = gb_hd_cport_allocate(hd, hd_cport_id, flags);
if (ret < 0) {
dev_err(&hd->dev, "failed to allocate cport: %d\n", ret);
goto err_unlock;
}
hd_cport_id = ret;
connection = kzalloc(sizeof(*connection), GFP_KERNEL);
if (!connection) {
ret = -ENOMEM;
goto err_hd_cport_release;
}
connection->hd_cport_id = hd_cport_id;
connection->intf_cport_id = cport_id;
connection->hd = hd;
connection->intf = intf;
connection->bundle = bundle;
connection->handler = handler;
connection->flags = flags;
if (intf && (intf->quirks & GB_INTERFACE_QUIRK_NO_CPORT_FEATURES))
connection->flags |= GB_CONNECTION_FLAG_NO_FLOWCTRL;
connection->state = GB_CONNECTION_STATE_DISABLED;
atomic_set(&connection->op_cycle, 0);
mutex_init(&connection->mutex);
spin_lock_init(&connection->lock);
INIT_LIST_HEAD(&connection->operations);
connection->wq = alloc_workqueue("%s:%d", WQ_UNBOUND, 1,
dev_name(&hd->dev), hd_cport_id);
if (!connection->wq) {
ret = -ENOMEM;
goto err_free_connection;
}
kref_init(&connection->kref);
gb_connection_init_name(connection);
spin_lock_irq(&gb_connections_lock);
list_add(&connection->hd_links, &hd->connections);
if (bundle)
list_add(&connection->bundle_links, &bundle->connections);
else
INIT_LIST_HEAD(&connection->bundle_links);
spin_unlock_irq(&gb_connections_lock);
mutex_unlock(&gb_connection_mutex);
trace_gb_connection_create(connection);
return connection;
err_free_connection:
kfree(connection);
err_hd_cport_release:
gb_hd_cport_release(hd, hd_cport_id);
err_unlock:
mutex_unlock(&gb_connection_mutex);
return ERR_PTR(ret);
}
struct gb_connection *
gb_connection_create_static(struct gb_host_device *hd, u16 hd_cport_id,
gb_request_handler_t handler)
{
return _gb_connection_create(hd, hd_cport_id, NULL, NULL, 0, handler,
GB_CONNECTION_FLAG_HIGH_PRIO);
}
struct gb_connection *
gb_connection_create_control(struct gb_interface *intf)
{
return _gb_connection_create(intf->hd, -1, intf, NULL, 0, NULL,
GB_CONNECTION_FLAG_CONTROL |
GB_CONNECTION_FLAG_HIGH_PRIO);
}
struct gb_connection *
gb_connection_create(struct gb_bundle *bundle, u16 cport_id,
gb_request_handler_t handler)
{
struct gb_interface *intf = bundle->intf;
return _gb_connection_create(intf->hd, -1, intf, bundle, cport_id,
handler, 0);
}
EXPORT_SYMBOL_GPL(gb_connection_create);
struct gb_connection *
gb_connection_create_flags(struct gb_bundle *bundle, u16 cport_id,
gb_request_handler_t handler,
unsigned long flags)
{
struct gb_interface *intf = bundle->intf;
if (WARN_ON_ONCE(flags & GB_CONNECTION_FLAG_CORE_MASK))
flags &= ~GB_CONNECTION_FLAG_CORE_MASK;
return _gb_connection_create(intf->hd, -1, intf, bundle, cport_id,
handler, flags);
}
EXPORT_SYMBOL_GPL(gb_connection_create_flags);
struct gb_connection *
gb_connection_create_offloaded(struct gb_bundle *bundle, u16 cport_id,
unsigned long flags)
{
flags |= GB_CONNECTION_FLAG_OFFLOADED;
return gb_connection_create_flags(bundle, cport_id, NULL, flags);
}
EXPORT_SYMBOL_GPL(gb_connection_create_offloaded);
static int gb_connection_hd_cport_enable(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->cport_enable)
return 0;
ret = hd->driver->cport_enable(hd, connection->hd_cport_id,
connection->flags);
if (ret) {
dev_err(&hd->dev, "%s: failed to enable host cport: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
static void gb_connection_hd_cport_disable(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->cport_disable)
return;
ret = hd->driver->cport_disable(hd, connection->hd_cport_id);
if (ret) {
dev_err(&hd->dev, "%s: failed to disable host cport: %d\n",
connection->name, ret);
}
}
static int gb_connection_hd_cport_connected(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->cport_connected)
return 0;
ret = hd->driver->cport_connected(hd, connection->hd_cport_id);
if (ret) {
dev_err(&hd->dev, "%s: failed to set connected state: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
static int gb_connection_hd_cport_flush(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->cport_flush)
return 0;
ret = hd->driver->cport_flush(hd, connection->hd_cport_id);
if (ret) {
dev_err(&hd->dev, "%s: failed to flush host cport: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
static int gb_connection_hd_cport_quiesce(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
size_t peer_space;
int ret;
if (!hd->driver->cport_quiesce)
return 0;
peer_space = sizeof(struct gb_operation_msg_hdr) +
sizeof(struct gb_cport_shutdown_request);
if (connection->mode_switch)
peer_space += sizeof(struct gb_operation_msg_hdr);
ret = hd->driver->cport_quiesce(hd, connection->hd_cport_id,
peer_space,
GB_CONNECTION_CPORT_QUIESCE_TIMEOUT);
if (ret) {
dev_err(&hd->dev, "%s: failed to quiesce host cport: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
static int gb_connection_hd_cport_clear(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->cport_clear)
return 0;
ret = hd->driver->cport_clear(hd, connection->hd_cport_id);
if (ret) {
dev_err(&hd->dev, "%s: failed to clear host cport: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
/*
* Request the SVC to create a connection from AP's cport to interface's
* cport.
*/
static int
gb_connection_svc_connection_create(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
struct gb_interface *intf;
u8 cport_flags;
int ret;
if (gb_connection_is_static(connection))
return 0;
intf = connection->intf;
/*
* Enable either E2EFC or CSD, unless no flow control is requested.
*/
cport_flags = GB_SVC_CPORT_FLAG_CSV_N;
if (gb_connection_flow_control_disabled(connection)) {
cport_flags |= GB_SVC_CPORT_FLAG_CSD_N;
} else if (gb_connection_e2efc_enabled(connection)) {
cport_flags |= GB_SVC_CPORT_FLAG_CSD_N |
GB_SVC_CPORT_FLAG_E2EFC;
}
ret = gb_svc_connection_create(hd->svc,
hd->svc->ap_intf_id,
connection->hd_cport_id,
intf->interface_id,
connection->intf_cport_id,
cport_flags);
if (ret) {
dev_err(&connection->hd->dev,
"%s: failed to create svc connection: %d\n",
connection->name, ret);
return ret;
}
return 0;
}
static void
gb_connection_svc_connection_destroy(struct gb_connection *connection)
{
if (gb_connection_is_static(connection))
return;
gb_svc_connection_destroy(connection->hd->svc,
connection->hd->svc->ap_intf_id,
connection->hd_cport_id,
connection->intf->interface_id,
connection->intf_cport_id);
}
/* Inform Interface about active CPorts */
static int gb_connection_control_connected(struct gb_connection *connection)
{
struct gb_control *control;
u16 cport_id = connection->intf_cport_id;
int ret;
if (gb_connection_is_static(connection))
return 0;
if (gb_connection_is_control(connection))
return 0;
control = connection->intf->control;
ret = gb_control_connected_operation(control, cport_id);
if (ret) {
dev_err(&connection->bundle->dev,
"failed to connect cport: %d\n", ret);
return ret;
}
return 0;
}
static void
gb_connection_control_disconnecting(struct gb_connection *connection)
{
struct gb_control *control;
u16 cport_id = connection->intf_cport_id;
int ret;
if (gb_connection_is_static(connection))
return;
control = connection->intf->control;
ret = gb_control_disconnecting_operation(control, cport_id);
if (ret) {
dev_err(&connection->hd->dev,
"%s: failed to send disconnecting: %d\n",
connection->name, ret);
}
}
static void
gb_connection_control_disconnected(struct gb_connection *connection)
{
struct gb_control *control;
u16 cport_id = connection->intf_cport_id;
int ret;
if (gb_connection_is_static(connection))
return;
control = connection->intf->control;
if (gb_connection_is_control(connection)) {
if (connection->mode_switch) {
ret = gb_control_mode_switch_operation(control);
if (ret) {
/*
* Allow mode switch to time out waiting for
* mailbox event.
*/
return;
}
}
return;
}
ret = gb_control_disconnected_operation(control, cport_id);
if (ret) {
dev_warn(&connection->bundle->dev,
"failed to disconnect cport: %d\n", ret);
}
}
static int gb_connection_shutdown_operation(struct gb_connection *connection,
u8 phase)
{
struct gb_cport_shutdown_request *req;
struct gb_operation *operation;
int ret;
operation = gb_operation_create_core(connection,
GB_REQUEST_TYPE_CPORT_SHUTDOWN,
sizeof(*req), 0, 0,
GFP_KERNEL);
if (!operation)
return -ENOMEM;
req = operation->request->payload;
req->phase = phase;
ret = gb_operation_request_send_sync(operation);
gb_operation_put(operation);
return ret;
}
static int gb_connection_cport_shutdown(struct gb_connection *connection,
u8 phase)
{
struct gb_host_device *hd = connection->hd;
const struct gb_hd_driver *drv = hd->driver;
int ret;
if (gb_connection_is_static(connection))
return 0;
if (gb_connection_is_offloaded(connection)) {
if (!drv->cport_shutdown)
return 0;
ret = drv->cport_shutdown(hd, connection->hd_cport_id, phase,
GB_OPERATION_TIMEOUT_DEFAULT);
} else {
ret = gb_connection_shutdown_operation(connection, phase);
}
if (ret) {
dev_err(&hd->dev, "%s: failed to send cport shutdown (phase %d): %d\n",
connection->name, phase, ret);
return ret;
}
return 0;
}
static int
gb_connection_cport_shutdown_phase_1(struct gb_connection *connection)
{
return gb_connection_cport_shutdown(connection, 1);
}
static int
gb_connection_cport_shutdown_phase_2(struct gb_connection *connection)
{
return gb_connection_cport_shutdown(connection, 2);
}
/*
* Cancel all active operations on a connection.
*
* Locking: Called with connection lock held and state set to DISABLED or
* DISCONNECTING.
*/
static void gb_connection_cancel_operations(struct gb_connection *connection,
int errno)
__must_hold(&connection->lock)
{
struct gb_operation *operation;
while (!list_empty(&connection->operations)) {
operation = list_last_entry(&connection->operations,
struct gb_operation, links);
gb_operation_get(operation);
spin_unlock_irq(&connection->lock);
if (gb_operation_is_incoming(operation))
gb_operation_cancel_incoming(operation, errno);
else
gb_operation_cancel(operation, errno);
gb_operation_put(operation);
spin_lock_irq(&connection->lock);
}
}
/*
* Cancel all active incoming operations on a connection.
*
* Locking: Called with connection lock held and state set to ENABLED_TX.
*/
static void
gb_connection_flush_incoming_operations(struct gb_connection *connection,
int errno)
__must_hold(&connection->lock)
{
struct gb_operation *operation;
bool incoming;
while (!list_empty(&connection->operations)) {
incoming = false;
list_for_each_entry(operation, &connection->operations,
links) {
if (gb_operation_is_incoming(operation)) {
gb_operation_get(operation);
incoming = true;
break;
}
}
if (!incoming)
break;
spin_unlock_irq(&connection->lock);
/* FIXME: flush, not cancel? */
gb_operation_cancel_incoming(operation, errno);
gb_operation_put(operation);
spin_lock_irq(&connection->lock);
}
}
/*
* _gb_connection_enable() - enable a connection
* @connection: connection to enable
* @rx: whether to enable incoming requests
*
* Connection-enable helper for DISABLED->ENABLED, DISABLED->ENABLED_TX, and
* ENABLED_TX->ENABLED state transitions.
*
* Locking: Caller holds connection->mutex.
*/
static int _gb_connection_enable(struct gb_connection *connection, bool rx)
{
int ret;
/* Handle ENABLED_TX -> ENABLED transitions. */
if (connection->state == GB_CONNECTION_STATE_ENABLED_TX) {
if (!(connection->handler && rx))
return 0;
spin_lock_irq(&connection->lock);
connection->state = GB_CONNECTION_STATE_ENABLED;
spin_unlock_irq(&connection->lock);
return 0;
}
ret = gb_connection_hd_cport_enable(connection);
if (ret)
return ret;
ret = gb_connection_svc_connection_create(connection);
if (ret)
goto err_hd_cport_clear;
ret = gb_connection_hd_cport_connected(connection);
if (ret)
goto err_svc_connection_destroy;
spin_lock_irq(&connection->lock);
if (connection->handler && rx)
connection->state = GB_CONNECTION_STATE_ENABLED;
else
connection->state = GB_CONNECTION_STATE_ENABLED_TX;
spin_unlock_irq(&connection->lock);
ret = gb_connection_control_connected(connection);
if (ret)
goto err_control_disconnecting;
return 0;
err_control_disconnecting:
spin_lock_irq(&connection->lock);
connection->state = GB_CONNECTION_STATE_DISCONNECTING;
gb_connection_cancel_operations(connection, -ESHUTDOWN);
spin_unlock_irq(&connection->lock);
/* Transmit queue should already be empty. */
gb_connection_hd_cport_flush(connection);
gb_connection_control_disconnecting(connection);
gb_connection_cport_shutdown_phase_1(connection);
gb_connection_hd_cport_quiesce(connection);
gb_connection_cport_shutdown_phase_2(connection);
gb_connection_control_disconnected(connection);
connection->state = GB_CONNECTION_STATE_DISABLED;
err_svc_connection_destroy:
gb_connection_svc_connection_destroy(connection);
err_hd_cport_clear:
gb_connection_hd_cport_clear(connection);
gb_connection_hd_cport_disable(connection);
return ret;
}
int gb_connection_enable(struct gb_connection *connection)
{
int ret = 0;
mutex_lock(&connection->mutex);
if (connection->state == GB_CONNECTION_STATE_ENABLED)
goto out_unlock;
ret = _gb_connection_enable(connection, true);
if (!ret)
trace_gb_connection_enable(connection);
out_unlock:
mutex_unlock(&connection->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(gb_connection_enable);
int gb_connection_enable_tx(struct gb_connection *connection)
{
int ret = 0;
mutex_lock(&connection->mutex);
if (connection->state == GB_CONNECTION_STATE_ENABLED) {
ret = -EINVAL;
goto out_unlock;
}
if (connection->state == GB_CONNECTION_STATE_ENABLED_TX)
goto out_unlock;
ret = _gb_connection_enable(connection, false);
if (!ret)
trace_gb_connection_enable(connection);
out_unlock:
mutex_unlock(&connection->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(gb_connection_enable_tx);
void gb_connection_disable_rx(struct gb_connection *connection)
{
mutex_lock(&connection->mutex);
spin_lock_irq(&connection->lock);
if (connection->state != GB_CONNECTION_STATE_ENABLED) {
spin_unlock_irq(&connection->lock);
goto out_unlock;
}
connection->state = GB_CONNECTION_STATE_ENABLED_TX;
gb_connection_flush_incoming_operations(connection, -ESHUTDOWN);
spin_unlock_irq(&connection->lock);
trace_gb_connection_disable(connection);
out_unlock:
mutex_unlock(&connection->mutex);
}
EXPORT_SYMBOL_GPL(gb_connection_disable_rx);
void gb_connection_mode_switch_prepare(struct gb_connection *connection)
{
connection->mode_switch = true;
}
void gb_connection_mode_switch_complete(struct gb_connection *connection)
{
gb_connection_svc_connection_destroy(connection);
gb_connection_hd_cport_clear(connection);
gb_connection_hd_cport_disable(connection);
connection->mode_switch = false;
}
void gb_connection_disable(struct gb_connection *connection)
{
mutex_lock(&connection->mutex);
if (connection->state == GB_CONNECTION_STATE_DISABLED)
goto out_unlock;
trace_gb_connection_disable(connection);
spin_lock_irq(&connection->lock);
connection->state = GB_CONNECTION_STATE_DISCONNECTING;
gb_connection_cancel_operations(connection, -ESHUTDOWN);
spin_unlock_irq(&connection->lock);
gb_connection_hd_cport_flush(connection);
gb_connection_control_disconnecting(connection);
gb_connection_cport_shutdown_phase_1(connection);
gb_connection_hd_cport_quiesce(connection);
gb_connection_cport_shutdown_phase_2(connection);
gb_connection_control_disconnected(connection);
connection->state = GB_CONNECTION_STATE_DISABLED;
/* control-connection tear down is deferred when mode switching */
if (!connection->mode_switch) {
gb_connection_svc_connection_destroy(connection);
gb_connection_hd_cport_clear(connection);
gb_connection_hd_cport_disable(connection);
}
out_unlock:
mutex_unlock(&connection->mutex);
}
EXPORT_SYMBOL_GPL(gb_connection_disable);
/* Disable a connection without communicating with the remote end. */
void gb_connection_disable_forced(struct gb_connection *connection)
{
mutex_lock(&connection->mutex);
if (connection->state == GB_CONNECTION_STATE_DISABLED)
goto out_unlock;
trace_gb_connection_disable(connection);
spin_lock_irq(&connection->lock);
connection->state = GB_CONNECTION_STATE_DISABLED;
gb_connection_cancel_operations(connection, -ESHUTDOWN);
spin_unlock_irq(&connection->lock);
gb_connection_hd_cport_flush(connection);
gb_connection_svc_connection_destroy(connection);
gb_connection_hd_cport_clear(connection);
gb_connection_hd_cport_disable(connection);
out_unlock:
mutex_unlock(&connection->mutex);
}
EXPORT_SYMBOL_GPL(gb_connection_disable_forced);
/* Caller must have disabled the connection before destroying it. */
void gb_connection_destroy(struct gb_connection *connection)
{
if (!connection)
return;
if (WARN_ON(connection->state != GB_CONNECTION_STATE_DISABLED))
gb_connection_disable(connection);
mutex_lock(&gb_connection_mutex);
spin_lock_irq(&gb_connections_lock);
list_del(&connection->bundle_links);
list_del(&connection->hd_links);
spin_unlock_irq(&gb_connections_lock);
destroy_workqueue(connection->wq);
gb_hd_cport_release(connection->hd, connection->hd_cport_id);
connection->hd_cport_id = CPORT_ID_BAD;
mutex_unlock(&gb_connection_mutex);
gb_connection_put(connection);
}
EXPORT_SYMBOL_GPL(gb_connection_destroy);
void gb_connection_latency_tag_enable(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->latency_tag_enable)
return;
ret = hd->driver->latency_tag_enable(hd, connection->hd_cport_id);
if (ret) {
dev_err(&connection->hd->dev,
"%s: failed to enable latency tag: %d\n",
connection->name, ret);
}
}
EXPORT_SYMBOL_GPL(gb_connection_latency_tag_enable);
void gb_connection_latency_tag_disable(struct gb_connection *connection)
{
struct gb_host_device *hd = connection->hd;
int ret;
if (!hd->driver->latency_tag_disable)
return;
ret = hd->driver->latency_tag_disable(hd, connection->hd_cport_id);
if (ret) {
dev_err(&connection->hd->dev,
"%s: failed to disable latency tag: %d\n",
connection->name, ret);
}
}
EXPORT_SYMBOL_GPL(gb_connection_latency_tag_disable);