* Greybus connections
*
* Copyright 2014 Google Inc.
+ * Copyright 2014 Linaro Ltd.
*
* Released under the GPLv2 only.
*/
-#include <linux/atomic.h>
+#include <linux/workqueue.h>
-#include "kernel_ver.h"
#include "greybus.h"
+#define GB_CONNECTION_TS_KFIFO_ELEMENTS 2
+#define GB_CONNECTION_TS_KFIFO_LEN \
+ (GB_CONNECTION_TS_KFIFO_ELEMENTS * sizeof(struct timeval))
+
static DEFINE_SPINLOCK(gb_connections_lock);
-static void _gb_hd_connection_insert(struct greybus_host_device *hd,
- struct gb_connection *connection)
+/* This is only used at initialization time; no locking is required. */
+static struct gb_connection *
+gb_connection_intf_find(struct gb_interface *intf, u16 cport_id)
{
- struct rb_root *root = &hd->connections;
- struct rb_node *node = &connection->hd_node;
- struct rb_node **link = &root->rb_node;
- struct rb_node *above = NULL;
- u16 cport_id = connection->hd_cport_id;
-
- while (*link) {
- struct gb_connection *connection;
-
- above = *link;
- connection = rb_entry(above, struct gb_connection, hd_node);
- if (connection->hd_cport_id > cport_id)
- link = &above->rb_left;
- else if (connection->hd_cport_id < cport_id)
- link = &above->rb_right;
- }
- rb_link_node(node, above, link);
- rb_insert_color(node, root);
-}
+ struct greybus_host_device *hd = intf->hd;
+ struct gb_connection *connection;
-static void _gb_hd_connection_remove(struct gb_connection *connection)
-{
- rb_erase(&connection->hd_node, &connection->hd->connections);
+ list_for_each_entry(connection, &hd->connections, hd_links)
+ if (connection->bundle->intf == intf &&
+ connection->intf_cport_id == cport_id)
+ return connection;
+ return NULL;
}
-struct gb_connection *gb_hd_connection_find(struct greybus_host_device *hd,
- u16 cport_id)
+static struct gb_connection *
+gb_connection_hd_find(struct greybus_host_device *hd, u16 cport_id)
{
- struct gb_connection *connection = NULL;
- struct rb_node *node;
+ struct gb_connection *connection;
+ unsigned long flags;
- spin_lock_irq(&gb_connections_lock);
- node = hd->connections.rb_node;
- while (node) {
- connection = rb_entry(node, struct gb_connection, hd_node);
- if (connection->hd_cport_id > cport_id)
- node = node->rb_left;
- else if (connection->hd_cport_id < cport_id)
- node = node->rb_right;
- else
+ spin_lock_irqsave(&gb_connections_lock, flags);
+ list_for_each_entry(connection, &hd->connections, hd_links)
+ if (connection->hd_cport_id == cport_id)
goto found;
- }
connection = NULL;
- found:
- spin_unlock_irq(&gb_connections_lock);
+found:
+ spin_unlock_irqrestore(&gb_connections_lock, flags);
return connection;
}
/*
- * Allocate an available CPort Id for use for the host side of the
- * given connection. The lowest-available id is returned, so the
- * first call is guaranteed to allocate CPort Id 0.
- *
- * Assigns the connection's hd_cport_id and returns true if successful.
- * Returns false otherwise.
+ * Callback from the host driver to let us know that data has been
+ * received on the bundle.
*/
-static bool gb_connection_hd_cport_id_alloc(struct gb_connection *connection)
+void greybus_data_rcvd(struct greybus_host_device *hd, u16 cport_id,
+ u8 *data, size_t length)
{
- struct ida *ida = &connection->hd->cport_id_map;
- int id;
+ struct gb_connection *connection;
- spin_lock(&connection->hd->cport_id_map_lock);
- id = ida_simple_get(ida, 0, HOST_DEV_CPORT_ID_MAX, GFP_KERNEL);
- spin_unlock(&connection->hd->cport_id_map_lock);
- if (id < 0)
- return false;
+ connection = gb_connection_hd_find(hd, cport_id);
+ if (!connection) {
+ dev_err(hd->parent,
+ "nonexistent connection (%zu bytes dropped)\n", length);
+ return;
+ }
+ gb_connection_recv(connection, data, length);
+}
+EXPORT_SYMBOL_GPL(greybus_data_rcvd);
- connection->hd_cport_id = (u16)id;
+void gb_connection_push_timestamp(struct gb_connection *connection)
+{
+ struct timeval tv;
- return true;
+ do_gettimeofday(&tv);
+ kfifo_in_locked(&connection->ts_kfifo, (void *)&tv,
+ sizeof(struct timeval), &connection->lock);
}
+EXPORT_SYMBOL_GPL(gb_connection_push_timestamp);
-/*
- * Free a previously-allocated CPort Id on the given host device.
- */
-static void gb_connection_hd_cport_id_free(struct gb_connection *connection)
+int gb_connection_pop_timestamp(struct gb_connection *connection,
+ struct timeval *tv)
{
- struct ida *ida = &connection->hd->cport_id_map;
+ int retval;
- spin_lock(&connection->hd->cport_id_map_lock);
- ida_simple_remove(ida, connection->hd_cport_id);
- spin_unlock(&connection->hd->cport_id_map_lock);
- connection->hd_cport_id = CPORT_ID_BAD;
+ if (!kfifo_len(&connection->ts_kfifo))
+ return -ENOMEM;
+ retval = kfifo_out_locked(&connection->ts_kfifo, (void *)tv,
+ sizeof(*tv), &connection->lock);
+ return retval;
}
+EXPORT_SYMBOL_GPL(gb_connection_pop_timestamp);
static ssize_t state_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct gb_connection *connection = to_gb_connection(dev);
+ enum gb_connection_state state;
- return sprintf(buf, "%d", connection->state);
+ spin_lock_irq(&connection->lock);
+ state = connection->state;
+ spin_unlock_irq(&connection->lock);
+
+ return sprintf(buf, "%d\n", state);
}
static DEVICE_ATTR_RO(state);
{
struct gb_connection *connection = to_gb_connection(dev);
- return sprintf(buf, "%d", connection->protocol->id);
+ if (connection->protocol)
+ return sprintf(buf, "%d\n", connection->protocol->id);
+ else
+ return -EINVAL;
}
static DEVICE_ATTR_RO(protocol_id);
{
struct gb_connection *connection = to_gb_connection(dev);
+ destroy_workqueue(connection->wq);
+ kfifo_free(&connection->ts_kfifo);
kfree(connection);
}
-static struct device_type greybus_connection_type = {
+struct device_type greybus_connection_type = {
.name = "greybus_connection",
.release = gb_connection_release,
};
+
+int svc_update_connection(struct gb_interface *intf,
+ struct gb_connection *connection)
+{
+ struct gb_bundle *bundle;
+
+ bundle = gb_bundle_create(intf, GB_SVC_BUNDLE_ID, GREYBUS_CLASS_SVC);
+ if (!bundle)
+ return -EINVAL;
+
+ device_del(&connection->dev);
+ connection->bundle = bundle;
+ connection->dev.parent = &bundle->dev;
+ dev_set_name(&connection->dev, "%s:%d", dev_name(&bundle->dev),
+ GB_SVC_CPORT_ID);
+
+ WARN_ON(device_add(&connection->dev));
+
+ spin_lock_irq(&gb_connections_lock);
+ list_add(&connection->bundle_links, &bundle->connections);
+ spin_unlock_irq(&gb_connections_lock);
+
+ return 0;
+}
+
/*
* Set up a Greybus connection, representing the bidirectional link
* between a CPort on a (local) Greybus host device and a CPort on
* Returns a pointer to the new connection if successful, or a null
* pointer otherwise.
*/
-struct gb_connection *gb_connection_create(struct gb_interface *interface,
- u16 cport_id, u8 protocol_id)
+struct gb_connection *
+gb_connection_create_range(struct greybus_host_device *hd,
+ struct gb_bundle *bundle, struct device *parent,
+ u16 cport_id, u8 protocol_id, u32 ida_start,
+ u32 ida_end)
{
struct gb_connection *connection;
- struct greybus_host_device *hd;
+ struct ida *id_map = &hd->cport_id_map;
+ int hd_cport_id;
int retval;
u8 major = 0;
u8 minor = 1;
- connection = kzalloc(sizeof(*connection), GFP_KERNEL);
- if (!connection)
+ /*
+ * If a manifest tries to reuse a cport, reject it. We
+ * initialize connections serially so we don't need to worry
+ * about holding the connection lock.
+ */
+ if (bundle && gb_connection_intf_find(bundle->intf, cport_id)) {
+ pr_err("duplicate interface cport id 0x%04hx\n", cport_id);
return NULL;
+ }
- INIT_LIST_HEAD(&connection->protocol_links);
- /* XXX Will have to establish connections to get version */
- if (!gb_protocol_get(connection, protocol_id, major, minor)) {
- pr_err("protocol 0x%02hhx not found\n", protocol_id);
- kfree(connection);
+ hd_cport_id = ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL);
+ if (hd_cport_id < 0)
return NULL;
- }
- hd = interface->gmod->hd;
+ connection = kzalloc(sizeof(*connection), GFP_KERNEL);
+ if (!connection)
+ goto err_remove_ida;
+
+ connection->hd_cport_id = hd_cport_id;
+ connection->intf_cport_id = cport_id;
connection->hd = hd;
- if (!gb_connection_hd_cport_id_alloc(connection)) {
- gb_protocol_put(connection);
- kfree(connection);
- return NULL;
- }
- connection->interface = interface;
- connection->interface_cport_id = cport_id;
+ connection->protocol_id = protocol_id;
+ connection->major = major;
+ connection->minor = minor;
+
+ connection->bundle = bundle;
connection->state = GB_CONNECTION_STATE_DISABLED;
- connection->dev.parent = &interface->dev;
- connection->dev.driver = NULL;
+ atomic_set(&connection->op_cycle, 0);
+ spin_lock_init(&connection->lock);
+ INIT_LIST_HEAD(&connection->operations);
+
+ connection->wq = alloc_workqueue("%s:%d", WQ_UNBOUND, 1,
+ dev_name(parent), cport_id);
+ if (!connection->wq)
+ goto err_free_connection;
+
+ if (kfifo_alloc(&connection->ts_kfifo, GB_CONNECTION_TS_KFIFO_LEN,
+ GFP_KERNEL))
+ goto err_destroy_wq;
+
+ connection->dev.parent = parent;
connection->dev.bus = &greybus_bus_type;
connection->dev.type = &greybus_connection_type;
connection->dev.groups = connection_groups;
device_initialize(&connection->dev);
dev_set_name(&connection->dev, "%s:%d",
- dev_name(&interface->dev), cport_id);
+ dev_name(parent), cport_id);
retval = device_add(&connection->dev);
if (retval) {
+ connection->hd_cport_id = CPORT_ID_BAD;
+ put_device(&connection->dev);
+
pr_err("failed to add connection device for cport 0x%04hx\n",
cport_id);
- gb_connection_hd_cport_id_free(connection);
- gb_protocol_put(connection);
- put_device(&connection->dev);
- return NULL;
+
+ goto err_remove_ida;
}
spin_lock_irq(&gb_connections_lock);
- _gb_hd_connection_insert(hd, connection);
- list_add_tail(&connection->interface_links, &interface->connections);
+ 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);
- INIT_LIST_HEAD(&connection->operations);
- connection->pending = RB_ROOT;
- atomic_set(&connection->op_cycle, 0);
+ if (hd_cport_id != GB_SVC_CPORT_ID) {
+ gb_svc_connection_create(hd->svc,
+ hd->endo->ap_intf_id, hd_cport_id,
+ bundle->intf->interface_id, cport_id);
+ }
+
+ gb_connection_bind_protocol(connection);
+ if (!connection->protocol)
+ dev_warn(&connection->dev,
+ "protocol 0x%02hhx handler not found\n", protocol_id);
return connection;
+
+err_destroy_wq:
+ destroy_workqueue(connection->wq);
+err_free_connection:
+ kfree(connection);
+err_remove_ida:
+ ida_simple_remove(id_map, hd_cport_id);
+
+ return NULL;
+}
+
+struct gb_connection *gb_connection_create(struct gb_bundle *bundle,
+ u16 cport_id, u8 protocol_id)
+{
+ return gb_connection_create_range(bundle->intf->hd, bundle,
+ &bundle->dev, cport_id, protocol_id,
+ 0, bundle->intf->hd->num_cports - 1);
}
/*
- * Tear down a previously set up connection.
+ * Cancel all active operations on a connection.
+ *
+ * Should only be called during connection tear down.
*/
-void gb_connection_destroy(struct gb_connection *connection)
+static void gb_connection_cancel_operations(struct gb_connection *connection,
+ int errno)
{
struct gb_operation *operation;
- struct gb_operation *next;
-
- if (WARN_ON(!connection))
- return;
- /* XXX Need to wait for any outstanding requests to complete */
- WARN_ON(!list_empty(&connection->operations));
+ spin_lock_irq(&connection->lock);
+ while (!list_empty(&connection->operations)) {
+ operation = list_last_entry(&connection->operations,
+ struct gb_operation, links);
+ gb_operation_get(operation);
+ spin_unlock_irq(&connection->lock);
- list_for_each_entry_safe(operation, next, &connection->operations,
- links) {
- gb_operation_cancel(operation);
- }
- spin_lock_irq(&gb_connections_lock);
- list_del(&connection->interface_links);
- _gb_hd_connection_remove(connection);
- spin_unlock_irq(&gb_connections_lock);
+ if (gb_operation_is_incoming(operation))
+ gb_operation_cancel_incoming(operation, errno);
+ else
+ gb_operation_cancel(operation, errno);
- gb_connection_hd_cport_id_free(connection);
- /* kref_put(connection->hd); */
- gb_protocol_put(connection);
+ gb_operation_put(operation);
- device_del(&connection->dev);
-}
-
-u16 gb_connection_operation_id(struct gb_connection *connection)
-{
- return (u16)(atomic_inc_return(&connection->op_cycle) & (int)U16_MAX);
+ spin_lock_irq(&connection->lock);
+ }
+ spin_unlock_irq(&connection->lock);
}
-void gb_connection_err(struct gb_connection *connection, const char *fmt, ...)
+static void gb_connection_disconnected(struct gb_connection *connection)
{
- struct va_format vaf;
- va_list args;
-
- va_start(args, fmt);
+ struct gb_control *control;
+ int cport_id = connection->intf_cport_id;
+ int ret;
- vaf.fmt = fmt;
- vaf.va = &args;
+ /*
+ * Inform Interface about In-active CPorts. We don't need to do this
+ * operation for control cport.
+ */
+ if ((cport_id == GB_CONTROL_CPORT_ID) ||
+ (connection->hd_cport_id == GB_SVC_CPORT_ID))
+ return;
- pr_err("greybus: [%hhu:%hhu:%hu]: %pV\n",
- connection->interface->gmod->module_id,
- connection->interface->id,
- connection->interface_cport_id, &vaf);
+ control = connection->bundle->intf->control;
- va_end(args);
+ ret = gb_control_disconnected_operation(control, cport_id);
+ if (ret)
+ dev_warn(&connection->dev,
+ "Failed to disconnect CPort-%d (%d)\n", cport_id, ret);
}
-/*
- * XXX Protocols should have a set of function pointers:
- * ->init (called here, to initialize the device)
- * ->input_handler
- * ->exit (reverse of init)
- */
-int gb_connection_init(struct gb_connection *connection)
+static int gb_connection_init(struct gb_connection *connection)
{
+ int cport_id = connection->intf_cport_id;
int ret;
+ /*
+ * Inform Interface about Active CPorts. We don't need to do this
+ * operation for control cport.
+ */
+ if (cport_id != GB_CONTROL_CPORT_ID &&
+ connection->hd_cport_id != GB_SVC_CPORT_ID) {
+ struct gb_control *control = connection->bundle->intf->control;
+
+ ret = gb_control_connected_operation(control, cport_id);
+ if (ret) {
+ dev_err(&connection->dev,
+ "Failed to connect CPort-%d (%d)\n",
+ cport_id, ret);
+ return ret;
+ }
+ }
+
/* Need to enable the connection to initialize it */
+ spin_lock_irq(&connection->lock);
connection->state = GB_CONNECTION_STATE_ENABLED;
- switch (connection->protocol->id) {
- case GREYBUS_PROTOCOL_I2C:
- connection->handler = &gb_i2c_connection_handler;
- break;
- case GREYBUS_PROTOCOL_GPIO:
- connection->handler = &gb_gpio_connection_handler;
- break;
- case GREYBUS_PROTOCOL_BATTERY:
- connection->handler = &gb_battery_connection_handler;
- break;
- case GREYBUS_PROTOCOL_UART:
- connection->handler = &gb_uart_connection_handler;
- break;
- case GREYBUS_PROTOCOL_CONTROL:
- case GREYBUS_PROTOCOL_AP:
- case GREYBUS_PROTOCOL_HID:
- case GREYBUS_PROTOCOL_LED:
- case GREYBUS_PROTOCOL_VENDOR:
- default:
- gb_connection_err(connection, "unimplemented protocol %hhu",
- connection->protocol->id);
- ret = -ENXIO;
- break;
+ spin_unlock_irq(&connection->lock);
+
+ /*
+ * Request protocol version supported by the module. We don't need to do
+ * this for SVC as that is initiated by the SVC.
+ */
+ if (connection->hd_cport_id != GB_SVC_CPORT_ID) {
+ ret = gb_protocol_get_version(connection);
+ if (ret) {
+ dev_err(&connection->dev,
+ "Failed to get version CPort-%d (%d)\n",
+ cport_id, ret);
+ goto disconnect;
+ }
}
- ret = connection->handler->connection_init(connection);
+ ret = connection->protocol->connection_init(connection);
+ if (!ret)
+ return 0;
- if (ret)
- connection->state = GB_CONNECTION_STATE_ERROR;
+disconnect:
+ spin_lock_irq(&connection->lock);
+ connection->state = GB_CONNECTION_STATE_ERROR;
+ spin_unlock_irq(&connection->lock);
+ gb_connection_disconnected(connection);
return ret;
}
-void gb_connection_exit(struct gb_connection *connection)
+static void gb_connection_exit(struct gb_connection *connection)
{
- if (!connection->handler) {
- gb_connection_err(connection, "uninitialized connection");
+ if (!connection->protocol)
+ return;
+
+ spin_lock_irq(&connection->lock);
+ if (connection->state != GB_CONNECTION_STATE_ENABLED) {
+ spin_unlock_irq(&connection->lock);
return;
}
connection->state = GB_CONNECTION_STATE_DESTROYING;
- connection->handler->connection_exit(connection);
+ spin_unlock_irq(&connection->lock);
+
+ gb_connection_cancel_operations(connection, -ESHUTDOWN);
+
+ connection->protocol->connection_exit(connection);
+ gb_connection_disconnected(connection);
+}
+
+/*
+ * Tear down a previously set up connection.
+ */
+void gb_connection_destroy(struct gb_connection *connection)
+{
+ struct ida *id_map;
+
+ if (WARN_ON(!connection))
+ return;
+
+ gb_connection_exit(connection);
+
+ spin_lock_irq(&gb_connections_lock);
+ list_del(&connection->bundle_links);
+ list_del(&connection->hd_links);
+ spin_unlock_irq(&gb_connections_lock);
+
+ if (connection->protocol)
+ gb_protocol_put(connection->protocol);
+ connection->protocol = NULL;
+
+ id_map = &connection->hd->cport_id_map;
+ ida_simple_remove(id_map, connection->hd_cport_id);
+ connection->hd_cport_id = CPORT_ID_BAD;
+
+ device_unregister(&connection->dev);
+}
+
+void gb_hd_connections_exit(struct greybus_host_device *hd)
+{
+ struct gb_connection *connection;
+
+ list_for_each_entry(connection, &hd->connections, hd_links)
+ gb_connection_destroy(connection);
+}
+
+int gb_connection_bind_protocol(struct gb_connection *connection)
+{
+ struct gb_protocol *protocol;
+ int ret;
+
+ /* If we already have a protocol bound here, just return */
+ if (connection->protocol)
+ return 0;
+
+ protocol = gb_protocol_get(connection->protocol_id,
+ connection->major,
+ connection->minor);
+ if (!protocol)
+ return 0;
+ connection->protocol = protocol;
+
+ /*
+ * If we have a valid device_id for the interface block, then we have an
+ * active device, so bring up the connection at the same time.
+ */
+ if ((!connection->bundle &&
+ connection->hd_cport_id == GB_SVC_CPORT_ID) ||
+ connection->bundle->intf->device_id != GB_DEVICE_ID_BAD) {
+ ret = gb_connection_init(connection);
+ if (ret) {
+ gb_protocol_put(protocol);
+ connection->protocol = NULL;
+ return ret;
+ }
+ }
+
+ return 0;
}
projects / cascardo / linux.git / blobdiff