1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
4 * Copyright (c) 2017, Linaro Ltd.
5 */
6#ifndef __QMI_HELPERS_H__
7#define __QMI_HELPERS_H__
8
9#include <linux/completion.h>
10#include <linux/idr.h>
11#include <linux/list.h>
12#include <linux/qrtr.h>
13#include <linux/types.h>
14#include <linux/workqueue.h>
15
16struct socket;
17
18/**
19 * struct qmi_header - wireformat header of QMI messages
20 * @type:	type of message
21 * @txn_id:	transaction id
22 * @msg_id:	message id
23 * @msg_len:	length of message payload following header
24 */
25struct qmi_header {
26	u8 type;
27	u16 txn_id;
28	u16 msg_id;
29	u16 msg_len;
30} __packed;
31
32#define QMI_REQUEST	0
33#define QMI_RESPONSE	2
34#define QMI_INDICATION	4
35
36#define QMI_COMMON_TLV_TYPE 0
37
38enum qmi_elem_type {
39	QMI_EOTI,
40	QMI_OPT_FLAG,
41	QMI_DATA_LEN,
42	QMI_UNSIGNED_1_BYTE,
43	QMI_UNSIGNED_2_BYTE,
44	QMI_UNSIGNED_4_BYTE,
45	QMI_UNSIGNED_8_BYTE,
46	QMI_SIGNED_2_BYTE_ENUM,
47	QMI_SIGNED_4_BYTE_ENUM,
48	QMI_STRUCT,
49	QMI_STRING,
50};
51
52enum qmi_array_type {
53	NO_ARRAY,
54	STATIC_ARRAY,
55	VAR_LEN_ARRAY,
56};
57
58/**
59 * struct qmi_elem_info - describes how to encode a single QMI element
60 * @data_type:	Data type of this element.
61 * @elem_len:	Array length of this element, if an array.
62 * @elem_size:	Size of a single instance of this data type.
63 * @array_type:	Array type of this element.
64 * @tlv_type:	QMI message specific type to identify which element
65 *		is present in an incoming message.
66 * @offset:	Specifies the offset of the first instance of this
67 *		element in the data structure.
68 * @ei_array:	Null-terminated array of @qmi_elem_info to describe nested
69 *		structures.
70 */
71struct qmi_elem_info {
72	enum qmi_elem_type data_type;
73	u32 elem_len;
74	u32 elem_size;
75	enum qmi_array_type array_type;
76	u8 tlv_type;
77	u32 offset;
78	const struct qmi_elem_info *ei_array;
79};
80
81#define QMI_RESULT_SUCCESS_V01			0
82#define QMI_RESULT_FAILURE_V01			1
83
84#define QMI_ERR_NONE_V01			0
85#define QMI_ERR_MALFORMED_MSG_V01		1
86#define QMI_ERR_NO_MEMORY_V01			2
87#define QMI_ERR_INTERNAL_V01			3
88#define QMI_ERR_CLIENT_IDS_EXHAUSTED_V01	5
89#define QMI_ERR_INVALID_ID_V01			41
90#define QMI_ERR_ENCODING_V01			58
91#define QMI_ERR_DISABLED_V01                    69
92#define QMI_ERR_INCOMPATIBLE_STATE_V01		90
93#define QMI_ERR_NOT_SUPPORTED_V01		94
94
95/**
96 * struct qmi_response_type_v01 - common response header (decoded)
97 * @result:	result of the transaction
98 * @error:	error value, when @result is QMI_RESULT_FAILURE_V01
99 */
100struct qmi_response_type_v01 {
101	u16 result;
102	u16 error;
103};
104
105extern const struct qmi_elem_info qmi_response_type_v01_ei[];
106
107/**
108 * struct qmi_service - context to track lookup-results
109 * @service:	service type
110 * @version:	version of the @service
111 * @instance:	instance id of the @service
112 * @node:	node of the service
113 * @port:	port of the service
114 * @priv:	handle for client's use
115 * @list_node:	list_head for house keeping
116 */
117struct qmi_service {
118	unsigned int service;
119	unsigned int version;
120	unsigned int instance;
121
122	unsigned int node;
123	unsigned int port;
124
125	void *priv;
126	struct list_head list_node;
127};
128
129struct qmi_handle;
130
131/**
132 * struct qmi_ops - callbacks for qmi_handle
133 * @new_server:		inform client of a new_server lookup-result, returning
134 *                      successfully from this call causes the library to call
135 *                      @del_server as the service is removed from the
136 *                      lookup-result. @priv of the qmi_service can be used by
137 *                      the client
138 * @del_server:		inform client of a del_server lookup-result
139 * @net_reset:		inform client that the name service was restarted and
140 *                      that and any state needs to be released
141 * @msg_handler:	invoked for incoming messages, allows a client to
142 *                      override the usual QMI message handler
143 * @bye:                inform a client that all clients from a node are gone
144 * @del_client:         inform a client that a particular client is gone
145 */
146struct qmi_ops {
147	int (*new_server)(struct qmi_handle *qmi, struct qmi_service *svc);
148	void (*del_server)(struct qmi_handle *qmi, struct qmi_service *svc);
149	void (*net_reset)(struct qmi_handle *qmi);
150	void (*msg_handler)(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
151			    const void *data, size_t count);
152	void (*bye)(struct qmi_handle *qmi, unsigned int node);
153	void (*del_client)(struct qmi_handle *qmi,
154			   unsigned int node, unsigned int port);
155};
156
157/**
158 * struct qmi_txn - transaction context
159 * @qmi:	QMI handle this transaction is associated with
160 * @id:		transaction id
161 * @lock:	for synchronization between handler and waiter of messages
162 * @completion:	completion object as the transaction receives a response
163 * @result:	result code for the completed transaction
164 * @ei:		description of the QMI encoded response (optional)
165 * @dest:	destination buffer to decode message into (optional)
166 */
167struct qmi_txn {
168	struct qmi_handle *qmi;
169
170	u16 id;
171
172	struct mutex lock;
173	struct completion completion;
174	int result;
175
176	const struct qmi_elem_info *ei;
177	void *dest;
178};
179
180/**
181 * struct qmi_msg_handler - description of QMI message handler
182 * @type:	type of message
183 * @msg_id:	message id
184 * @ei:		description of the QMI encoded message
185 * @decoded_size:	size of the decoded object
186 * @fn:		function to invoke as the message is decoded
187 */
188struct qmi_msg_handler {
189	unsigned int type;
190	unsigned int msg_id;
191
192	const struct qmi_elem_info *ei;
193
194	size_t decoded_size;
195	void (*fn)(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
196		   struct qmi_txn *txn, const void *decoded);
197};
198
199/**
200 * struct qmi_handle - QMI context
201 * @sock:	socket handle
202 * @sock_lock:	synchronization of @sock modifications
203 * @sq:		sockaddr of @sock
204 * @work:	work for handling incoming messages
205 * @wq:		workqueue to post @work on
206 * @recv_buf:	scratch buffer for handling incoming messages
207 * @recv_buf_size:	size of @recv_buf
208 * @lookups:		list of registered lookup requests
209 * @lookup_results:	list of lookup-results advertised to the client
210 * @services:		list of registered services (by this client)
211 * @ops:	reference to callbacks
212 * @txns:	outstanding transactions
213 * @txn_lock:	lock for modifications of @txns
214 * @handlers:	list of handlers for incoming messages
215 */
216struct qmi_handle {
217	struct socket *sock;
218	struct mutex sock_lock;
219
220	struct sockaddr_qrtr sq;
221
222	struct work_struct work;
223	struct workqueue_struct *wq;
224
225	void *recv_buf;
226	size_t recv_buf_size;
227
228	struct list_head lookups;
229	struct list_head lookup_results;
230	struct list_head services;
231
232	struct qmi_ops ops;
233
234	struct idr txns;
235	struct mutex txn_lock;
236
237	const struct qmi_msg_handler *handlers;
238};
239
240int qmi_add_lookup(struct qmi_handle *qmi, unsigned int service,
241		   unsigned int version, unsigned int instance);
242int qmi_add_server(struct qmi_handle *qmi, unsigned int service,
243		   unsigned int version, unsigned int instance);
244
245int qmi_handle_init(struct qmi_handle *qmi, size_t max_msg_len,
246		    const struct qmi_ops *ops,
247		    const struct qmi_msg_handler *handlers);
248void qmi_handle_release(struct qmi_handle *qmi);
249
250ssize_t qmi_send_request(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
251			 struct qmi_txn *txn, int msg_id, size_t len,
252			 const struct qmi_elem_info *ei, const void *c_struct);
253ssize_t qmi_send_response(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
254			  struct qmi_txn *txn, int msg_id, size_t len,
255			  const struct qmi_elem_info *ei, const void *c_struct);
256ssize_t qmi_send_indication(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
257			    int msg_id, size_t len, const struct qmi_elem_info *ei,
258			    const void *c_struct);
259
260void *qmi_encode_message(int type, unsigned int msg_id, size_t *len,
261			 unsigned int txn_id, const struct qmi_elem_info *ei,
262			 const void *c_struct);
263
264int qmi_decode_message(const void *buf, size_t len,
265		       const struct qmi_elem_info *ei, void *c_struct);
266
267int qmi_txn_init(struct qmi_handle *qmi, struct qmi_txn *txn,
268		 const struct qmi_elem_info *ei, void *c_struct);
269int qmi_txn_wait(struct qmi_txn *txn, unsigned long timeout);
270void qmi_txn_cancel(struct qmi_txn *txn);
271
272#endif
273