2014-10-02 02:54:15 +00:00
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/*
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* Greybus operations
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*
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* Copyright 2014 Google Inc.
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*
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* Released under the GPLv2 only.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/workqueue.h>
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#include "greybus.h"
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2014-10-16 11:35:31 +00:00
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/*
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* The top bit of the type in an operation message header indicates
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* whether the message is a request (bit clear) or response (bit set)
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*/
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#define GB_OPERATION_TYPE_RESPONSE 0x80
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2014-10-27 07:40:09 +00:00
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#define OPERATION_TIMEOUT_DEFAULT 1000 /* milliseconds */
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2014-10-22 07:04:28 +00:00
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2014-10-16 11:35:33 +00:00
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/*
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* XXX This needs to be coordinated with host driver parameters
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2014-11-18 00:08:32 +00:00
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* XXX May need to reduce to allow for message header within a page
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2014-10-16 11:35:33 +00:00
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*/
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#define GB_OPERATION_MESSAGE_SIZE_MAX 4096
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2014-10-20 15:27:56 +00:00
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static struct kmem_cache *gb_operation_cache;
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2014-10-16 11:35:34 +00:00
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/* Workqueue to handle Greybus operation completions. */
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static struct workqueue_struct *gb_operation_recv_workqueue;
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2014-10-02 02:54:15 +00:00
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/*
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* All operation messages (both requests and responses) begin with
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2014-11-19 23:55:03 +00:00
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* a header that encodes the size of the data (header included).
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* This header also contains a unique identifier, which is used to
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* keep track of in-flight operations. The header contains an
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* operation type field, whose interpretation is dependent on what
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* type of protocol is used over the connection.
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*
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* The high bit (0x80) of the operation type field is used to
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* indicate whether the message is a request (clear) or a response
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* (set).
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*
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* Response messages include an additional status byte, which
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* communicates the result of the corresponding request. A zero
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* status value means the operation completed successfully. Any
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* other value indicates an error; in this case, the payload of the
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* response message (if any) is ignored. The status byte must be
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* zero in the header for a request message.
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2014-10-02 02:54:15 +00:00
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*
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* The wire format for all numeric fields in the header is little
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* endian. Any operation-specific data begins immediately after the
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* header, and is 64-bit aligned.
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*/
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struct gb_operation_msg_hdr {
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2014-11-19 18:27:16 +00:00
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__le16 size; /* Size in bytes of header + payload */
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__le16 operation_id; /* Operation unique id */
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__u8 type; /* E.g GB_I2C_TYPE_* or GB_GPIO_TYPE_* */
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2014-11-19 23:55:03 +00:00
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__u8 result; /* Result of request (in responses only) */
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/* 2 bytes pad, must be zero (ignore when read) */
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2014-10-02 02:54:15 +00:00
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} __aligned(sizeof(u64));
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/* XXX Could be per-host device, per-module, or even per-connection */
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static DEFINE_SPINLOCK(gb_operations_lock);
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2014-11-12 21:17:53 +00:00
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static void gb_pending_operation_insert(struct gb_operation *operation)
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2014-10-16 11:35:32 +00:00
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{
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struct gb_connection *connection = operation->connection;
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struct gb_operation_msg_hdr *header;
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2014-11-12 21:17:54 +00:00
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/*
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* Assign the operation's id and move it into its
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* connection's pending list.
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2014-10-16 11:35:32 +00:00
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*/
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spin_lock_irq(&gb_operations_lock);
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2014-11-12 21:17:54 +00:00
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operation->id = ++connection->op_cycle;
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2014-11-12 21:17:53 +00:00
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list_move_tail(&operation->links, &connection->pending);
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2014-10-16 11:35:32 +00:00
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spin_unlock_irq(&gb_operations_lock);
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2014-11-12 21:17:54 +00:00
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/* Store the operation id in the request header */
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2014-11-20 22:09:14 +00:00
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header = operation->request.header;
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2014-11-19 18:27:16 +00:00
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header->operation_id = cpu_to_le16(operation->id);
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2014-10-16 11:35:32 +00:00
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}
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2014-11-12 21:17:53 +00:00
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static void gb_pending_operation_remove(struct gb_operation *operation)
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2014-10-16 11:35:32 +00:00
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{
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2014-10-22 07:04:28 +00:00
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struct gb_connection *connection = operation->connection;
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2014-10-27 07:40:09 +00:00
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/* Take us off of the list of pending operations */
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2014-10-16 11:35:32 +00:00
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spin_lock_irq(&gb_operations_lock);
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2014-11-12 21:17:53 +00:00
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list_move_tail(&operation->links, &connection->operations);
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2014-10-16 11:35:32 +00:00
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spin_unlock_irq(&gb_operations_lock);
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}
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static struct gb_operation *
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2014-11-19 18:27:16 +00:00
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gb_pending_operation_find(struct gb_connection *connection, u16 operation_id)
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2014-10-16 11:35:32 +00:00
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{
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2014-11-12 21:17:53 +00:00
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struct gb_operation *operation;
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2014-10-16 11:35:32 +00:00
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bool found = false;
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spin_lock_irq(&gb_operations_lock);
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2014-11-12 21:17:53 +00:00
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list_for_each_entry(operation, &connection->pending, links)
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2014-11-19 18:27:16 +00:00
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if (operation->id == operation_id) {
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2014-10-16 11:35:32 +00:00
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found = true;
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2014-11-12 21:17:53 +00:00
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break;
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}
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2014-10-16 11:35:32 +00:00
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spin_unlock_irq(&gb_operations_lock);
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return found ? operation : NULL;
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}
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2014-11-18 19:26:48 +00:00
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static int gb_message_send(struct gb_message *message, gfp_t gfp_mask)
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2014-11-18 00:08:37 +00:00
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{
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2014-11-18 19:26:52 +00:00
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struct gb_connection *connection = message->operation->connection;
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2014-11-18 19:26:53 +00:00
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u16 dest_cport_id = connection->interface_cport_id;
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2014-11-19 18:27:15 +00:00
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int ret = 0;
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2014-11-18 19:26:48 +00:00
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2014-11-18 19:26:52 +00:00
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message->cookie = connection->hd->driver->buffer_send(connection->hd,
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2014-11-18 19:26:53 +00:00
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dest_cport_id,
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2014-11-20 22:09:14 +00:00
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message->header,
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message->size,
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2014-11-18 19:26:48 +00:00
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gfp_mask);
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2014-11-18 19:26:51 +00:00
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if (IS_ERR(message->cookie)) {
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2014-11-19 18:27:15 +00:00
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ret = PTR_ERR(message->cookie);
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2014-11-18 19:26:51 +00:00
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message->cookie = NULL;
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2014-11-18 19:26:46 +00:00
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}
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2014-11-19 18:27:15 +00:00
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return ret;
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2014-11-18 00:08:37 +00:00
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}
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2014-11-19 18:27:15 +00:00
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/*
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* Cancel a message whose buffer we have passed to the host device
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* layer to be sent.
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*/
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2014-11-18 19:26:49 +00:00
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static void gb_message_cancel(struct gb_message *message)
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2014-11-18 00:08:37 +00:00
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{
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2014-11-18 19:26:52 +00:00
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struct greybus_host_device *hd;
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2014-11-19 18:27:15 +00:00
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if (!message->cookie)
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return; /* Don't bother if the message isn't in flight */
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2014-11-18 00:08:37 +00:00
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2014-11-18 19:26:52 +00:00
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hd = message->operation->connection->hd;
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hd->driver->buffer_cancel(message->cookie);
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2014-11-18 00:08:37 +00:00
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}
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2014-11-18 19:26:44 +00:00
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2014-10-02 02:54:15 +00:00
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/*
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* An operations's response message has arrived. If no callback was
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* supplied it was submitted for asynchronous completion, so we notify
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* any waiters. Otherwise we assume calling the completion is enough
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* and nobody else will be waiting.
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*/
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2014-10-27 07:40:09 +00:00
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static void gb_operation_complete(struct gb_operation *operation)
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2014-10-02 02:54:15 +00:00
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{
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if (operation->callback)
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operation->callback(operation);
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else
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complete_all(&operation->completion);
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}
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2014-10-16 11:35:34 +00:00
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/* Wait for a submitted operation to complete */
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2014-10-02 02:54:15 +00:00
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int gb_operation_wait(struct gb_operation *operation)
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{
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int ret;
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ret = wait_for_completion_interruptible(&operation->completion);
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/* If interrupted, cancel the in-flight buffer */
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if (ret < 0)
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2014-11-18 19:26:49 +00:00
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gb_message_cancel(&operation->request);
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2014-10-02 02:54:15 +00:00
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return ret;
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}
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2014-10-16 11:35:34 +00:00
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static void gb_operation_request_handle(struct gb_operation *operation)
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{
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2014-11-05 22:12:55 +00:00
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struct gb_protocol *protocol = operation->connection->protocol;
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struct gb_operation_msg_hdr *header;
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2014-10-16 11:35:34 +00:00
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2014-11-20 22:09:14 +00:00
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header = operation->request.header;
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2014-11-12 21:17:55 +00:00
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2014-11-05 22:12:55 +00:00
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/*
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* If the protocol has no incoming request handler, report
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* an error and mark the request bad.
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*/
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if (protocol->request_recv) {
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2014-11-12 21:17:55 +00:00
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protocol->request_recv(header->type, operation);
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2014-11-19 11:55:00 +00:00
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return;
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2014-10-16 11:35:34 +00:00
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}
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2014-10-29 00:35:59 +00:00
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gb_connection_err(operation->connection,
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2014-11-05 22:12:55 +00:00
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"unexpected incoming request type 0x%02hhx\n", header->type);
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2014-10-16 11:35:34 +00:00
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operation->result = GB_OP_PROTOCOL_BAD;
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}
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2014-10-02 02:54:15 +00:00
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/*
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2014-10-16 11:35:34 +00:00
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* Either this operation contains an incoming request, or its
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* response has arrived. An incoming request will have a null
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* response buffer pointer (it is the responsibility of the request
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* handler to allocate and fill in the response buffer).
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2014-10-02 02:54:15 +00:00
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*/
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2014-10-16 11:35:34 +00:00
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static void gb_operation_recv_work(struct work_struct *recv_work)
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2014-10-02 02:54:15 +00:00
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{
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2014-10-16 11:35:32 +00:00
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struct gb_operation *operation;
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2014-10-16 11:35:34 +00:00
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bool incoming_request;
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2014-10-16 11:35:32 +00:00
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2014-10-16 11:35:34 +00:00
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operation = container_of(recv_work, struct gb_operation, recv_work);
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2014-11-20 22:09:14 +00:00
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incoming_request = operation->response.header == NULL;
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2014-10-16 11:35:34 +00:00
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if (incoming_request)
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gb_operation_request_handle(operation);
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gb_operation_complete(operation);
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}
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2014-10-27 07:40:09 +00:00
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/*
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* Timeout call for the operation.
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*
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* If this fires, something went wrong, so mark the result as timed out, and
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* run the completion handler, which (hopefully) should clean up the operation
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* properly.
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*/
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static void operation_timeout(struct work_struct *work)
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{
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struct gb_operation *operation;
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operation = container_of(work, struct gb_operation, timeout_work.work);
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2014-11-13 12:44:35 +00:00
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pr_debug("%s: timeout!\n", __func__);
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2014-10-27 07:40:09 +00:00
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operation->result = GB_OP_TIMEOUT;
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gb_operation_complete(operation);
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}
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2014-11-20 22:09:13 +00:00
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static void *
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gb_buffer_alloc(struct greybus_host_device *hd, size_t size, gfp_t gfp_flags)
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{
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u8 *buffer;
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buffer = kzalloc(hd->buffer_headroom + size, gfp_flags);
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if (buffer)
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buffer += hd->buffer_headroom;
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return buffer;
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}
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static void
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gb_buffer_free(struct greybus_host_device *hd, void *buffer)
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{
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u8 *allocated = buffer;
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if (allocated)
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kfree(allocated - hd->buffer_headroom);
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}
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2014-10-02 02:54:15 +00:00
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/*
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2014-10-16 11:35:31 +00:00
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* Allocate a buffer to be used for an operation request or response
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2014-10-16 11:35:34 +00:00
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* message. For outgoing messages, both types of message contain a
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* common header, which is filled in here. Incoming requests or
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* responses also contain the same header, but there's no need to
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* initialize it here (it'll be overwritten by the incoming
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* message).
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2014-10-16 11:35:31 +00:00
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*/
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2014-11-18 00:08:32 +00:00
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static int gb_operation_message_init(struct gb_operation *operation,
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u8 type, size_t size,
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2014-11-18 19:26:54 +00:00
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bool request, gfp_t gfp_flags)
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2014-10-16 11:35:31 +00:00
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{
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2014-11-17 14:08:43 +00:00
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struct gb_connection *connection = operation->connection;
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2014-11-18 00:08:33 +00:00
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struct greybus_host_device *hd = connection->hd;
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2014-11-18 00:08:32 +00:00
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struct gb_message *message;
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2014-10-16 11:35:31 +00:00
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struct gb_operation_msg_hdr *header;
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2014-11-18 00:08:35 +00:00
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size += sizeof(*header);
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2014-11-20 22:09:13 +00:00
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if (size > hd->buffer_size_max)
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return -E2BIG;
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2014-11-17 14:08:39 +00:00
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2014-11-18 00:08:32 +00:00
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if (request) {
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message = &operation->request;
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} else {
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message = &operation->response;
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type |= GB_OPERATION_TYPE_RESPONSE;
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}
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2014-11-18 00:08:35 +00:00
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2014-11-20 22:09:14 +00:00
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message->header = gb_buffer_alloc(hd, size, gfp_flags);
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if (!message->header)
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2014-11-18 19:26:42 +00:00
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return -ENOMEM;
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2014-11-20 22:09:14 +00:00
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message->size = size;
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2014-10-16 11:35:31 +00:00
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/* Fill in the header structure */
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2014-11-20 22:09:14 +00:00
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header = message->header;
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2014-10-16 11:35:31 +00:00
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header->size = cpu_to_le16(size);
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2014-11-19 18:27:16 +00:00
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header->operation_id = 0; /* Filled in when submitted */
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2014-10-16 11:35:31 +00:00
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header->type = type;
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2014-11-18 00:08:32 +00:00
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message->payload = header + 1;
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message->operation = operation;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void gb_operation_message_exit(struct gb_message *message)
|
|
|
|
{
|
2014-11-18 19:26:52 +00:00
|
|
|
struct greybus_host_device *hd;
|
|
|
|
|
|
|
|
hd = message->operation->connection->hd;
|
2014-11-20 22:09:14 +00:00
|
|
|
gb_buffer_free(hd, message->header);
|
2014-11-18 19:26:52 +00:00
|
|
|
|
2014-11-18 00:08:32 +00:00
|
|
|
message->operation = NULL;
|
|
|
|
message->payload = NULL;
|
2014-11-20 22:09:14 +00:00
|
|
|
message->header = NULL;
|
|
|
|
message->size = 0;
|
2014-10-16 11:35:31 +00:00
|
|
|
}
|
|
|
|
|
2014-11-19 23:55:04 +00:00
|
|
|
/*
|
|
|
|
* Map an enum gb_operation_status value (which is represted in a
|
|
|
|
* message as a single back a single byte) to an appropriate Linux
|
|
|
|
* negative errno.
|
|
|
|
*/
|
|
|
|
int gb_operation_status_map(u8 status)
|
|
|
|
{
|
|
|
|
switch (status) {
|
|
|
|
case GB_OP_SUCCESS:
|
|
|
|
return 0;
|
|
|
|
case GB_OP_INVALID:
|
|
|
|
return -EINVAL;
|
|
|
|
case GB_OP_NO_MEMORY:
|
|
|
|
return -ENOMEM;
|
|
|
|
case GB_OP_INTERRUPTED:
|
|
|
|
return -EINTR;
|
|
|
|
case GB_OP_RETRY:
|
|
|
|
return -EAGAIN;
|
|
|
|
case GB_OP_PROTOCOL_BAD:
|
|
|
|
return -EPROTONOSUPPORT;
|
|
|
|
case GB_OP_OVERFLOW:
|
|
|
|
return -E2BIG;
|
|
|
|
case GB_OP_TIMEOUT:
|
|
|
|
return -ETIMEDOUT;
|
|
|
|
default:
|
|
|
|
return -EIO;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2014-10-16 11:35:31 +00:00
|
|
|
/*
|
|
|
|
* Create a Greybus operation to be sent over the given connection.
|
|
|
|
* The request buffer will big enough for a payload of the given
|
|
|
|
* size. Outgoing requests must specify the size of the response
|
|
|
|
* buffer size, which must be sufficient to hold all expected
|
|
|
|
* response data.
|
|
|
|
*
|
|
|
|
* Incoming requests will supply a response size of 0, and in that
|
|
|
|
* case no response buffer is allocated. (A response always
|
|
|
|
* includes a status byte, so 0 is not a valid size.) Whatever
|
|
|
|
* handles the operation request is responsible for allocating the
|
|
|
|
* response buffer.
|
2014-10-02 02:54:15 +00:00
|
|
|
*
|
2014-10-16 11:35:31 +00:00
|
|
|
* Returns a pointer to the new operation or a null pointer if an
|
|
|
|
* error occurs.
|
2014-10-02 02:54:15 +00:00
|
|
|
*/
|
2014-11-19 23:55:02 +00:00
|
|
|
static struct gb_operation *
|
|
|
|
gb_operation_create_common(struct gb_connection *connection, bool outgoing,
|
|
|
|
u8 type, size_t request_size,
|
|
|
|
size_t response_size)
|
2014-10-02 02:54:15 +00:00
|
|
|
{
|
|
|
|
struct gb_operation *operation;
|
2014-10-16 11:35:31 +00:00
|
|
|
gfp_t gfp_flags = response_size ? GFP_KERNEL : GFP_ATOMIC;
|
2014-11-18 00:08:32 +00:00
|
|
|
int ret;
|
2014-10-02 02:54:15 +00:00
|
|
|
|
2014-10-20 15:27:56 +00:00
|
|
|
operation = kmem_cache_zalloc(gb_operation_cache, gfp_flags);
|
2014-10-02 02:54:15 +00:00
|
|
|
if (!operation)
|
|
|
|
return NULL;
|
2014-10-27 09:58:54 +00:00
|
|
|
operation->connection = connection;
|
2014-10-02 02:54:15 +00:00
|
|
|
|
2014-11-18 00:08:32 +00:00
|
|
|
ret = gb_operation_message_init(operation, type, request_size,
|
2014-11-18 19:26:54 +00:00
|
|
|
true, gfp_flags);
|
2014-11-18 00:08:32 +00:00
|
|
|
if (ret)
|
2014-10-20 15:27:56 +00:00
|
|
|
goto err_cache;
|
2014-10-16 11:35:31 +00:00
|
|
|
|
2014-10-16 11:35:34 +00:00
|
|
|
if (outgoing) {
|
2014-11-18 00:08:32 +00:00
|
|
|
ret = gb_operation_message_init(operation, type, response_size,
|
2014-11-18 19:26:54 +00:00
|
|
|
false, GFP_KERNEL);
|
2014-11-18 00:08:32 +00:00
|
|
|
if (ret)
|
2014-10-20 15:27:56 +00:00
|
|
|
goto err_request;
|
2014-10-16 11:35:31 +00:00
|
|
|
}
|
2014-10-02 02:54:15 +00:00
|
|
|
|
2014-10-16 11:35:34 +00:00
|
|
|
INIT_WORK(&operation->recv_work, gb_operation_recv_work);
|
2014-10-02 02:54:15 +00:00
|
|
|
operation->callback = NULL; /* set at submit time */
|
|
|
|
init_completion(&operation->completion);
|
2014-10-27 07:40:09 +00:00
|
|
|
INIT_DELAYED_WORK(&operation->timeout_work, operation_timeout);
|
2014-11-17 14:08:40 +00:00
|
|
|
kref_init(&operation->kref);
|
2014-10-02 02:54:15 +00:00
|
|
|
|
|
|
|
spin_lock_irq(&gb_operations_lock);
|
|
|
|
list_add_tail(&operation->links, &connection->operations);
|
|
|
|
spin_unlock_irq(&gb_operations_lock);
|
|
|
|
|
|
|
|
return operation;
|
2014-10-20 15:27:56 +00:00
|
|
|
|
|
|
|
err_request:
|
2014-11-18 00:08:32 +00:00
|
|
|
gb_operation_message_exit(&operation->request);
|
2014-10-20 15:27:56 +00:00
|
|
|
err_cache:
|
|
|
|
kmem_cache_free(gb_operation_cache, operation);
|
|
|
|
|
|
|
|
return NULL;
|
2014-10-02 02:54:15 +00:00
|
|
|
}
|
|
|
|
|
2014-11-19 23:55:02 +00:00
|
|
|
struct gb_operation *gb_operation_create(struct gb_connection *connection,
|
|
|
|
u8 type, size_t request_size,
|
|
|
|
size_t response_size)
|
|
|
|
{
|
|
|
|
return gb_operation_create_common(connection, true, type,
|
|
|
|
request_size, response_size);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct gb_operation *
|
|
|
|
gb_operation_create_incoming(struct gb_connection *connection,
|
|
|
|
u8 type, size_t request_size,
|
|
|
|
size_t response_size)
|
|
|
|
{
|
|
|
|
return gb_operation_create_common(connection, false, type,
|
|
|
|
request_size, response_size);
|
|
|
|
}
|
|
|
|
|
2014-10-02 02:54:15 +00:00
|
|
|
/*
|
|
|
|
* Destroy a previously created operation.
|
|
|
|
*/
|
2014-11-17 14:08:40 +00:00
|
|
|
static void _gb_operation_destroy(struct kref *kref)
|
2014-10-02 02:54:15 +00:00
|
|
|
{
|
2014-11-17 14:08:40 +00:00
|
|
|
struct gb_operation *operation;
|
|
|
|
|
|
|
|
operation = container_of(kref, struct gb_operation, kref);
|
2014-10-02 02:54:15 +00:00
|
|
|
|
|
|
|
/* XXX Make sure it's not in flight */
|
|
|
|
spin_lock_irq(&gb_operations_lock);
|
|
|
|
list_del(&operation->links);
|
|
|
|
spin_unlock_irq(&gb_operations_lock);
|
|
|
|
|
2014-11-18 00:08:32 +00:00
|
|
|
gb_operation_message_exit(&operation->response);
|
|
|
|
gb_operation_message_exit(&operation->request);
|
2014-10-02 02:54:15 +00:00
|
|
|
|
2014-10-20 15:27:56 +00:00
|
|
|
kmem_cache_free(gb_operation_cache, operation);
|
2014-10-02 02:54:15 +00:00
|
|
|
}
|
2014-10-16 11:35:33 +00:00
|
|
|
|
2014-11-17 14:08:40 +00:00
|
|
|
void gb_operation_put(struct gb_operation *operation)
|
|
|
|
{
|
|
|
|
if (!WARN_ON(!operation))
|
|
|
|
kref_put(&operation->kref, _gb_operation_destroy);
|
|
|
|
}
|
|
|
|
|
2014-10-16 11:35:33 +00:00
|
|
|
/*
|
|
|
|
* Send an operation request message. The caller has filled in
|
|
|
|
* any payload so the request message is ready to go. If non-null,
|
|
|
|
* the callback function supplied will be called when the response
|
|
|
|
* message has arrived indicating the operation is complete. A null
|
|
|
|
* callback function is used for a synchronous request; return from
|
|
|
|
* this function won't occur until the operation is complete (or an
|
|
|
|
* interrupt occurs).
|
|
|
|
*/
|
|
|
|
int gb_operation_request_send(struct gb_operation *operation,
|
|
|
|
gb_operation_callback callback)
|
|
|
|
{
|
2014-11-12 21:17:52 +00:00
|
|
|
unsigned long timeout;
|
2014-10-16 11:35:33 +00:00
|
|
|
int ret;
|
|
|
|
|
2014-10-22 07:04:30 +00:00
|
|
|
if (operation->connection->state != GB_CONNECTION_STATE_ENABLED)
|
|
|
|
return -ENOTCONN;
|
|
|
|
|
2014-10-16 11:35:33 +00:00
|
|
|
/*
|
|
|
|
* XXX
|
|
|
|
* I think the order of operations is going to be
|
|
|
|
* significant, and if so, we may need a mutex to surround
|
2014-11-18 19:26:51 +00:00
|
|
|
* setting the operation id and submitting the buffer.
|
2014-10-16 11:35:33 +00:00
|
|
|
*/
|
|
|
|
operation->callback = callback;
|
2014-11-12 21:17:53 +00:00
|
|
|
gb_pending_operation_insert(operation);
|
2014-11-20 21:37:06 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* We impose a time limit for requests to complete. We need
|
|
|
|
* to set the timer before we send the request though, so we
|
|
|
|
* don't lose a race with the receipt of the resposne.
|
|
|
|
*/
|
|
|
|
timeout = msecs_to_jiffies(OPERATION_TIMEOUT_DEFAULT);
|
|
|
|
schedule_delayed_work(&operation->timeout_work, timeout);
|
|
|
|
|
|
|
|
/* All set, send the request */
|
2014-11-18 19:26:48 +00:00
|
|
|
ret = gb_message_send(&operation->request, GFP_KERNEL);
|
2014-10-16 11:35:33 +00:00
|
|
|
if (ret)
|
|
|
|
return ret;
|
2014-11-12 21:17:52 +00:00
|
|
|
|
2014-10-16 11:35:33 +00:00
|
|
|
if (!callback)
|
|
|
|
ret = gb_operation_wait(operation);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Send a response for an incoming operation request.
|
|
|
|
*/
|
|
|
|
int gb_operation_response_send(struct gb_operation *operation)
|
|
|
|
{
|
|
|
|
gb_operation_destroy(operation);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2014-10-16 11:35:34 +00:00
|
|
|
/*
|
2014-11-19 18:27:17 +00:00
|
|
|
* We've received data on a connection, and it doesn't look like a
|
|
|
|
* response, so we assume it's a request.
|
2014-11-17 14:08:39 +00:00
|
|
|
*
|
|
|
|
* This is called in interrupt context, so just copy the incoming
|
2014-11-19 18:27:17 +00:00
|
|
|
* data into the request buffer and handle the rest via workqueue.
|
|
|
|
*/
|
|
|
|
void gb_connection_recv_request(struct gb_connection *connection,
|
|
|
|
u16 operation_id, u8 type, void *data, size_t size)
|
|
|
|
{
|
|
|
|
struct gb_operation *operation;
|
|
|
|
|
2014-11-19 23:55:02 +00:00
|
|
|
operation = gb_operation_create_incoming(connection, type, size, 0);
|
2014-11-19 18:27:17 +00:00
|
|
|
if (!operation) {
|
|
|
|
gb_connection_err(connection, "can't create operation");
|
|
|
|
return; /* XXX Respond with pre-allocated ENOMEM */
|
|
|
|
}
|
|
|
|
operation->id = operation_id;
|
2014-11-20 22:09:14 +00:00
|
|
|
memcpy(operation->request.header, data, size);
|
2014-11-19 18:27:17 +00:00
|
|
|
|
|
|
|
/* The rest will be handled in work queue context */
|
|
|
|
queue_work(gb_operation_recv_workqueue, &operation->recv_work);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We've received data that appears to be an operation response
|
|
|
|
* message. Look up the operation, and record that we've received
|
|
|
|
* its repsonse.
|
2014-11-17 14:08:39 +00:00
|
|
|
*
|
2014-11-19 18:27:17 +00:00
|
|
|
* This is called in interrupt context, so just copy the incoming
|
|
|
|
* data into the response buffer and handle the rest via workqueue.
|
|
|
|
*/
|
|
|
|
static void gb_connection_recv_response(struct gb_connection *connection,
|
|
|
|
u16 operation_id, void *data, size_t size)
|
|
|
|
{
|
|
|
|
struct gb_operation *operation;
|
|
|
|
struct gb_message *message;
|
2014-11-19 23:55:03 +00:00
|
|
|
struct gb_operation_msg_hdr *header;
|
2014-11-19 18:27:17 +00:00
|
|
|
|
|
|
|
operation = gb_pending_operation_find(connection, operation_id);
|
|
|
|
if (!operation) {
|
|
|
|
gb_connection_err(connection, "operation not found");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
cancel_delayed_work(&operation->timeout_work);
|
|
|
|
gb_pending_operation_remove(operation);
|
|
|
|
|
|
|
|
message = &operation->response;
|
2014-11-20 22:09:14 +00:00
|
|
|
if (size <= message->size) {
|
2014-11-20 21:37:07 +00:00
|
|
|
/* Transfer the operation result from the response header */
|
2014-11-20 22:09:14 +00:00
|
|
|
header = message->header;
|
2014-11-20 21:37:07 +00:00
|
|
|
operation->result = header->result;
|
|
|
|
} else {
|
2014-11-19 18:27:17 +00:00
|
|
|
gb_connection_err(connection, "recv buffer too small");
|
2014-11-20 21:37:07 +00:00
|
|
|
operation->result = GB_OP_OVERFLOW;
|
2014-11-19 18:27:17 +00:00
|
|
|
}
|
|
|
|
|
2014-11-19 23:55:05 +00:00
|
|
|
/* We must ignore the payload if a bad status is returned */
|
2014-11-19 23:55:03 +00:00
|
|
|
if (operation->result == GB_OP_SUCCESS)
|
2014-11-20 22:09:14 +00:00
|
|
|
memcpy(message->header, data, size);
|
2014-11-19 18:27:17 +00:00
|
|
|
|
|
|
|
/* The rest will be handled in work queue context */
|
|
|
|
queue_work(gb_operation_recv_workqueue, &operation->recv_work);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Handle data arriving on a connection. As soon as we return the
|
|
|
|
* supplied data buffer will be reused (so unless we do something
|
|
|
|
* with, it's effectively dropped).
|
2014-10-16 11:35:34 +00:00
|
|
|
*/
|
2014-11-18 19:26:50 +00:00
|
|
|
void gb_connection_recv(struct gb_connection *connection,
|
2014-10-16 11:35:33 +00:00
|
|
|
void *data, size_t size)
|
|
|
|
{
|
|
|
|
struct gb_operation_msg_hdr *header;
|
2014-11-19 18:27:17 +00:00
|
|
|
size_t msg_size;
|
|
|
|
u16 operation_id;
|
2014-10-16 11:35:33 +00:00
|
|
|
|
2014-11-19 18:27:17 +00:00
|
|
|
if (connection->state != GB_CONNECTION_STATE_ENABLED) {
|
|
|
|
gb_connection_err(connection, "dropping %zu received bytes",
|
|
|
|
size);
|
2014-10-22 07:04:30 +00:00
|
|
|
return;
|
2014-11-19 18:27:17 +00:00
|
|
|
}
|
2014-10-22 07:04:30 +00:00
|
|
|
|
2014-11-17 14:08:39 +00:00
|
|
|
if (size < sizeof(*header)) {
|
|
|
|
gb_connection_err(connection, "message too small");
|
2014-10-16 11:35:33 +00:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
header = data;
|
2014-11-19 18:27:17 +00:00
|
|
|
msg_size = (size_t)le16_to_cpu(header->size);
|
|
|
|
if (msg_size > size) {
|
|
|
|
gb_connection_err(connection, "incomplete message");
|
|
|
|
return; /* XXX Should still complete operation */
|
2014-10-16 11:35:33 +00:00
|
|
|
}
|
|
|
|
|
2014-11-19 18:27:17 +00:00
|
|
|
operation_id = le16_to_cpu(header->operation_id);
|
|
|
|
if (header->type & GB_OPERATION_TYPE_RESPONSE)
|
|
|
|
gb_connection_recv_response(connection, operation_id,
|
|
|
|
data, msg_size);
|
|
|
|
else
|
|
|
|
gb_connection_recv_request(connection, operation_id,
|
|
|
|
header->type, data, msg_size);
|
2014-10-16 11:35:34 +00:00
|
|
|
}
|
|
|
|
|
2014-10-22 07:04:29 +00:00
|
|
|
/*
|
|
|
|
* Cancel an operation.
|
|
|
|
*/
|
|
|
|
void gb_operation_cancel(struct gb_operation *operation)
|
|
|
|
{
|
|
|
|
operation->canceled = true;
|
2014-11-18 19:26:49 +00:00
|
|
|
gb_message_cancel(&operation->request);
|
2014-11-20 22:09:14 +00:00
|
|
|
if (operation->response.header)
|
2014-11-18 19:26:49 +00:00
|
|
|
gb_message_cancel(&operation->response);
|
2014-10-22 07:04:29 +00:00
|
|
|
}
|
|
|
|
|
2014-10-16 11:35:34 +00:00
|
|
|
int gb_operation_init(void)
|
|
|
|
{
|
2014-10-20 15:27:56 +00:00
|
|
|
gb_operation_cache = kmem_cache_create("gb_operation_cache",
|
|
|
|
sizeof(struct gb_operation), 0, 0, NULL);
|
|
|
|
if (!gb_operation_cache)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
2014-10-16 11:35:34 +00:00
|
|
|
gb_operation_recv_workqueue = alloc_workqueue("greybus_recv", 0, 1);
|
2014-10-20 15:27:56 +00:00
|
|
|
if (!gb_operation_recv_workqueue) {
|
|
|
|
kmem_cache_destroy(gb_operation_cache);
|
|
|
|
gb_operation_cache = NULL;
|
2014-10-16 11:35:34 +00:00
|
|
|
return -ENOMEM;
|
2014-10-20 15:27:56 +00:00
|
|
|
}
|
2014-10-16 11:35:34 +00:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
void gb_operation_exit(void)
|
|
|
|
{
|
|
|
|
destroy_workqueue(gb_operation_recv_workqueue);
|
2014-10-20 15:27:56 +00:00
|
|
|
gb_operation_recv_workqueue = NULL;
|
2014-11-14 11:55:00 +00:00
|
|
|
kmem_cache_destroy(gb_operation_cache);
|
|
|
|
gb_operation_cache = NULL;
|
2014-10-16 11:35:33 +00:00
|
|
|
}
|