71f6c3231c
The AP must enable the FCT flow of APBA once it has received the response from the AP that the connection between APBA and a module has been setted up. Disable the flow of FCT tokens when destroying connections. Signed-off-by: Fabien Parent <fparent@baylibre.com> Reviewed-by: Johan Hovold <johan@hovoldconsulting.com> Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
671 lines
16 KiB
C
671 lines
16 KiB
C
/*
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* Greybus connections
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*
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* Copyright 2014 Google Inc.
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* Copyright 2014 Linaro Ltd.
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*
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* Released under the GPLv2 only.
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*/
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#include <linux/workqueue.h>
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#include "greybus.h"
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static void gb_connection_kref_release(struct kref *kref);
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static DEFINE_SPINLOCK(gb_connections_lock);
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static DEFINE_MUTEX(gb_connection_mutex);
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/* Caller holds gb_connection_mutex. */
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static struct gb_connection *
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gb_connection_intf_find(struct gb_interface *intf, u16 cport_id)
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{
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struct gb_host_device *hd = intf->hd;
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struct gb_connection *connection;
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list_for_each_entry(connection, &hd->connections, hd_links) {
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if (connection->intf == intf &&
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connection->intf_cport_id == cport_id)
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return connection;
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}
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return NULL;
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}
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static void gb_connection_get(struct gb_connection *connection)
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{
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kref_get(&connection->kref);
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}
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static void gb_connection_put(struct gb_connection *connection)
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{
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kref_put(&connection->kref, gb_connection_kref_release);
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}
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/*
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* Returns a reference-counted pointer to the connection if found.
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*/
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static struct gb_connection *
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gb_connection_hd_find(struct gb_host_device *hd, u16 cport_id)
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{
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struct gb_connection *connection;
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unsigned long flags;
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spin_lock_irqsave(&gb_connections_lock, flags);
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list_for_each_entry(connection, &hd->connections, hd_links)
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if (connection->hd_cport_id == cport_id) {
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gb_connection_get(connection);
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goto found;
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}
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connection = NULL;
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found:
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spin_unlock_irqrestore(&gb_connections_lock, flags);
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return connection;
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}
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/*
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* Callback from the host driver to let us know that data has been
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* received on the bundle.
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*/
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void greybus_data_rcvd(struct gb_host_device *hd, u16 cport_id,
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u8 *data, size_t length)
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{
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struct gb_connection *connection;
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connection = gb_connection_hd_find(hd, cport_id);
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if (!connection) {
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dev_err(&hd->dev,
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"nonexistent connection (%zu bytes dropped)\n", length);
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return;
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}
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gb_connection_recv(connection, data, length);
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gb_connection_put(connection);
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}
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EXPORT_SYMBOL_GPL(greybus_data_rcvd);
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static void gb_connection_kref_release(struct kref *kref)
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{
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struct gb_connection *connection;
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connection = container_of(kref, struct gb_connection, kref);
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kfree(connection);
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}
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static void gb_connection_init_name(struct gb_connection *connection)
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{
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u16 hd_cport_id = connection->hd_cport_id;
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u16 cport_id = 0;
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u8 intf_id = 0;
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if (connection->intf) {
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intf_id = connection->intf->interface_id;
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cport_id = connection->intf_cport_id;
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}
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snprintf(connection->name, sizeof(connection->name),
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"%u/%u:%u", hd_cport_id, intf_id, cport_id);
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}
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/*
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* _gb_connection_create() - create a Greybus connection
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* @hd: host device of the connection
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* @hd_cport_id: host-device cport id, or -1 for dynamic allocation
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* @intf: remote interface, or NULL for static connections
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* @bundle: remote-interface bundle (may be NULL)
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* @cport_id: remote-interface cport id, or 0 for static connections
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* @handler: request handler (may be NULL)
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*
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* Create a Greybus connection, representing the bidirectional link
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* between a CPort on a (local) Greybus host device and a CPort on
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* another Greybus interface.
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*
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* A connection also maintains the state of operations sent over the
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* connection.
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*
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* Serialised against concurrent create and destroy using the
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* gb_connection_mutex.
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*
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* Return: A pointer to the new connection if successful, or an ERR_PTR
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* otherwise.
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*/
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static struct gb_connection *
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_gb_connection_create(struct gb_host_device *hd, int hd_cport_id,
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struct gb_interface *intf,
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struct gb_bundle *bundle, int cport_id,
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gb_request_handler_t handler)
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{
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struct gb_connection *connection;
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struct ida *id_map = &hd->cport_id_map;
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int ida_start, ida_end;
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int ret;
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if (hd_cport_id < 0) {
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ida_start = 0;
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ida_end = hd->num_cports;
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} else if (hd_cport_id < hd->num_cports) {
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ida_start = hd_cport_id;
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ida_end = hd_cport_id + 1;
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} else {
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dev_err(&hd->dev, "cport %d not available\n", hd_cport_id);
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return ERR_PTR(-EINVAL);
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}
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mutex_lock(&gb_connection_mutex);
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if (intf && gb_connection_intf_find(intf, cport_id)) {
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dev_err(&intf->dev, "cport %u already in use\n", cport_id);
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ret = -EBUSY;
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goto err_unlock;
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}
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ret = ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL);
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if (ret < 0)
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goto err_unlock;
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hd_cport_id = ret;
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connection = kzalloc(sizeof(*connection), GFP_KERNEL);
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if (!connection) {
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ret = -ENOMEM;
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goto err_remove_ida;
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}
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connection->hd_cport_id = hd_cport_id;
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connection->intf_cport_id = cport_id;
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connection->hd = hd;
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connection->intf = intf;
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connection->bundle = bundle;
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connection->handler = handler;
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connection->state = GB_CONNECTION_STATE_DISABLED;
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atomic_set(&connection->op_cycle, 0);
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mutex_init(&connection->mutex);
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spin_lock_init(&connection->lock);
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INIT_LIST_HEAD(&connection->operations);
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connection->wq = alloc_workqueue("%s:%d", WQ_UNBOUND, 1,
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dev_name(&hd->dev), hd_cport_id);
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if (!connection->wq) {
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ret = -ENOMEM;
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goto err_free_connection;
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}
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kref_init(&connection->kref);
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gb_connection_init_name(connection);
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spin_lock_irq(&gb_connections_lock);
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list_add(&connection->hd_links, &hd->connections);
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if (bundle)
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list_add(&connection->bundle_links, &bundle->connections);
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else
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INIT_LIST_HEAD(&connection->bundle_links);
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spin_unlock_irq(&gb_connections_lock);
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mutex_unlock(&gb_connection_mutex);
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return connection;
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err_free_connection:
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kfree(connection);
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err_remove_ida:
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ida_simple_remove(id_map, hd_cport_id);
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err_unlock:
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mutex_unlock(&gb_connection_mutex);
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return ERR_PTR(ret);
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}
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struct gb_connection *
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gb_connection_create_static(struct gb_host_device *hd, u16 hd_cport_id,
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gb_request_handler_t handler)
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{
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return _gb_connection_create(hd, hd_cport_id, NULL, NULL, 0, handler);
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}
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struct gb_connection *
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gb_connection_create_control(struct gb_interface *intf)
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{
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return _gb_connection_create(intf->hd, -1, intf, NULL, 0, NULL);
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}
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struct gb_connection *
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gb_connection_create(struct gb_bundle *bundle, u16 cport_id,
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gb_request_handler_t handler)
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{
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struct gb_interface *intf = bundle->intf;
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return _gb_connection_create(intf->hd, -1, intf, bundle, cport_id,
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handler);
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}
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EXPORT_SYMBOL_GPL(gb_connection_create);
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static int gb_connection_hd_cport_enable(struct gb_connection *connection)
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{
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struct gb_host_device *hd = connection->hd;
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int ret;
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if (!hd->driver->cport_enable)
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return 0;
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ret = hd->driver->cport_enable(hd, connection->hd_cport_id);
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if (ret) {
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dev_err(&hd->dev,
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"failed to enable host cport: %d\n", ret);
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return ret;
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}
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return 0;
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}
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static void gb_connection_hd_cport_disable(struct gb_connection *connection)
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{
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struct gb_host_device *hd = connection->hd;
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if (!hd->driver->cport_disable)
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return;
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hd->driver->cport_disable(hd, connection->hd_cport_id);
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}
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static int gb_connection_hd_fct_flow_enable(struct gb_connection *connection)
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{
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struct gb_host_device *hd = connection->hd;
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int ret;
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if (!hd->driver->fct_flow_enable)
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return 0;
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ret = hd->driver->fct_flow_enable(hd, connection->hd_cport_id);
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if (ret) {
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dev_err(&hd->dev, "%s: failed to enable FCT flow: %d\n",
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connection->name, ret);
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return ret;
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}
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return 0;
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}
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static void gb_connection_hd_fct_flow_disable(struct gb_connection *connection)
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{
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struct gb_host_device *hd = connection->hd;
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if (!hd->driver->fct_flow_disable)
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return;
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hd->driver->fct_flow_disable(hd, connection->hd_cport_id);
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}
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/*
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* Request the SVC to create a connection from AP's cport to interface's
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* cport.
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*/
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static int
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gb_connection_svc_connection_create(struct gb_connection *connection)
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{
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struct gb_host_device *hd = connection->hd;
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struct gb_interface *intf;
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int ret;
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if (gb_connection_is_static(connection))
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return gb_connection_hd_fct_flow_enable(connection);
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intf = connection->intf;
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ret = gb_svc_connection_create(hd->svc,
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hd->svc->ap_intf_id,
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connection->hd_cport_id,
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intf->interface_id,
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connection->intf_cport_id,
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intf->boot_over_unipro);
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if (ret) {
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dev_err(&connection->hd->dev,
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"%s: failed to create svc connection: %d\n",
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connection->name, ret);
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return ret;
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}
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ret = gb_connection_hd_fct_flow_enable(connection);
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if (ret) {
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gb_svc_connection_destroy(hd->svc, hd->svc->ap_intf_id,
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connection->hd_cport_id,
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intf->interface_id,
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connection->intf_cport_id);
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return ret;
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}
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return 0;
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}
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static void
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gb_connection_svc_connection_destroy(struct gb_connection *connection)
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{
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gb_connection_hd_fct_flow_disable(connection);
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if (gb_connection_is_static(connection))
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return;
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gb_svc_connection_destroy(connection->hd->svc,
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connection->hd->svc->ap_intf_id,
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connection->hd_cport_id,
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connection->intf->interface_id,
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connection->intf_cport_id);
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}
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/* Inform Interface about active CPorts */
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static int gb_connection_control_connected(struct gb_connection *connection)
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{
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struct gb_control *control;
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u16 cport_id = connection->intf_cport_id;
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int ret;
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if (gb_connection_is_static(connection))
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return 0;
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control = connection->intf->control;
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if (connection == control->connection)
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return 0;
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ret = gb_control_connected_operation(control, cport_id);
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if (ret) {
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dev_err(&connection->bundle->dev,
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"failed to connect cport: %d\n", ret);
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return ret;
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}
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return 0;
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}
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/* Inform Interface about inactive CPorts */
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static void
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gb_connection_control_disconnected(struct gb_connection *connection)
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{
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struct gb_control *control;
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u16 cport_id = connection->intf_cport_id;
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int ret;
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if (gb_connection_is_static(connection))
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return;
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control = connection->intf->control;
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if (connection == control->connection)
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return;
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ret = gb_control_disconnected_operation(control, cport_id);
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if (ret) {
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dev_warn(&connection->bundle->dev,
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"failed to disconnect cport: %d\n", ret);
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}
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}
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/*
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* Cancel all active operations on a connection.
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*
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* Locking: Called with connection lock held and state set to DISABLED.
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*/
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static void gb_connection_cancel_operations(struct gb_connection *connection,
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int errno)
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__must_hold(&connection->lock)
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{
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struct gb_operation *operation;
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while (!list_empty(&connection->operations)) {
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operation = list_last_entry(&connection->operations,
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struct gb_operation, links);
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gb_operation_get(operation);
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spin_unlock_irq(&connection->lock);
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if (gb_operation_is_incoming(operation))
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gb_operation_cancel_incoming(operation, errno);
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else
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gb_operation_cancel(operation, errno);
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gb_operation_put(operation);
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spin_lock_irq(&connection->lock);
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}
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}
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/*
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* Cancel all active incoming operations on a connection.
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*
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* Locking: Called with connection lock held and state set to ENABLED_TX.
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*/
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static void
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gb_connection_flush_incoming_operations(struct gb_connection *connection,
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int errno)
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__must_hold(&connection->lock)
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{
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struct gb_operation *operation;
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bool incoming;
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while (!list_empty(&connection->operations)) {
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incoming = false;
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list_for_each_entry(operation, &connection->operations,
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links) {
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if (gb_operation_is_incoming(operation)) {
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gb_operation_get(operation);
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incoming = true;
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break;
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}
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}
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if (!incoming)
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break;
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spin_unlock_irq(&connection->lock);
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/* FIXME: flush, not cancel? */
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gb_operation_cancel_incoming(operation, errno);
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gb_operation_put(operation);
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spin_lock_irq(&connection->lock);
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}
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}
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/*
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* _gb_connection_enable() - enable a connection
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* @connection: connection to enable
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* @rx: whether to enable incoming requests
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*
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* Connection-enable helper for DISABLED->ENABLED, DISABLED->ENABLED_TX, and
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* ENABLED_TX->ENABLED state transitions.
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*
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* Locking: Caller holds connection->mutex.
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*/
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static int _gb_connection_enable(struct gb_connection *connection, bool rx)
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{
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int ret;
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/* Handle ENABLED_TX -> ENABLED transitions. */
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if (connection->state == GB_CONNECTION_STATE_ENABLED_TX) {
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if (!(connection->handler && rx))
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return 0;
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spin_lock_irq(&connection->lock);
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connection->state = GB_CONNECTION_STATE_ENABLED;
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spin_unlock_irq(&connection->lock);
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return 0;
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}
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ret = gb_connection_hd_cport_enable(connection);
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if (ret)
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return ret;
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ret = gb_connection_svc_connection_create(connection);
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if (ret)
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goto err_hd_cport_disable;
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spin_lock_irq(&connection->lock);
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if (connection->handler && rx)
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connection->state = GB_CONNECTION_STATE_ENABLED;
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else
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connection->state = GB_CONNECTION_STATE_ENABLED_TX;
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spin_unlock_irq(&connection->lock);
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ret = gb_connection_control_connected(connection);
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if (ret)
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goto err_svc_destroy;
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return 0;
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err_svc_destroy:
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spin_lock_irq(&connection->lock);
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connection->state = GB_CONNECTION_STATE_DISABLED;
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gb_connection_cancel_operations(connection, -ESHUTDOWN);
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spin_unlock_irq(&connection->lock);
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gb_connection_svc_connection_destroy(connection);
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err_hd_cport_disable:
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gb_connection_hd_cport_disable(connection);
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return ret;
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}
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int gb_connection_enable(struct gb_connection *connection)
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{
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int ret = 0;
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mutex_lock(&connection->mutex);
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if (connection->state == GB_CONNECTION_STATE_ENABLED)
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goto out_unlock;
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ret = _gb_connection_enable(connection, true);
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out_unlock:
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mutex_unlock(&connection->mutex);
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return ret;
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}
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EXPORT_SYMBOL_GPL(gb_connection_enable);
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int gb_connection_enable_tx(struct gb_connection *connection)
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|
{
|
|
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);
|
|
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);
|
|
|
|
out_unlock:
|
|
mutex_unlock(&connection->mutex);
|
|
}
|
|
|
|
void gb_connection_disable(struct gb_connection *connection)
|
|
{
|
|
mutex_lock(&connection->mutex);
|
|
|
|
if (connection->state == GB_CONNECTION_STATE_DISABLED)
|
|
goto out_unlock;
|
|
|
|
gb_connection_control_disconnected(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_svc_connection_destroy(connection);
|
|
gb_connection_hd_cport_disable(connection);
|
|
|
|
out_unlock:
|
|
mutex_unlock(&connection->mutex);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gb_connection_disable);
|
|
|
|
/* Caller must have disabled the connection before destroying it. */
|
|
void gb_connection_destroy(struct gb_connection *connection)
|
|
{
|
|
struct ida *id_map;
|
|
|
|
if (!connection)
|
|
return;
|
|
|
|
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);
|
|
|
|
id_map = &connection->hd->cport_id_map;
|
|
ida_simple_remove(id_map, 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);
|