xref: /aosp_15_r20/external/libwebsockets/lib/drivers/i2c/lws-i2c.c (revision 1c60b9aca93fdbc9b5f19b2d2194c91294b22281)
1 /*
2  * Generic I2C
3  *
4  * Copyright (C) 2019 - 2020 Andy Green <[email protected]>
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22  * IN THE SOFTWARE.
23  *
24  * These are generic helpers made up of calls to the i2c driver ops, so they
25  * just need implementing once like this and are usable for any i2c underlying
26  * implementation via the ops.
27  */
28 
29 #include <libwebsockets.h>
30 
31 int
lws_i2c_command(const lws_i2c_ops_t * ctx,uint8_t ads7,uint8_t c)32 lws_i2c_command(const lws_i2c_ops_t *ctx, uint8_t ads7, uint8_t c)
33 {
34 	if (ctx->start(ctx))
35 		return 1;
36 
37 	if (ctx->write(ctx, ads7 << 1)) {
38 		ctx->stop(ctx);
39 
40 		return 1;
41 	}
42 
43 	ctx->write(ctx, 0);
44 	ctx->write(ctx, c);
45 	ctx->stop(ctx);
46 
47 	return 0;
48 }
49 
50 int
lws_i2c_command_list(const lws_i2c_ops_t * ctx,uint8_t ads7,const uint8_t * buf,size_t len)51 lws_i2c_command_list(const lws_i2c_ops_t *ctx, uint8_t ads7, const uint8_t *buf,
52 		     size_t len)
53 {
54 	while (len--)
55 		if (lws_i2c_command(ctx, ads7, *buf++))
56 			return 1;
57 
58 	return 0;
59 }
60