1 /*
2  * Generic I2C ops
3  *
4  * Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
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  * This is like an abstract class for spi, a real implementation provides
25  * functions for the ops that use the underlying OS arrangements.
26  *
27  * It uses descriptor / queuing semantics but eg the GPIO BB implementantion is
28  * synchronous.
29  */
30 
31 #if !defined(__LWS_SPI_H__)
32 #define __LWS_SPI_H__
33 
34 #include <stdint.h>
35 #include <stddef.h>
36 
37 typedef int (*lws_spi_cb_t)(void *opaque);
38 
39 enum {
40 	LWSSPIMODE_CPOL					= (1 << 0),
41 	LWSSPIMODE_CPHA					= (1 << 1),
42 
43 	LWS_SPI_BUSMODE_CLK_IDLE_LOW_SAMP_RISING	= 0,
44 	LWS_SPI_BUSMODE_CLK_IDLE_HIGH_SAMP_RISING	= LWSSPIMODE_CPOL,
45 	LWS_SPI_BUSMODE_CLK_IDLE_LOW_SAMP_FALLING	= LWSSPIMODE_CPHA,
46 	LWS_SPI_BUSMODE_CLK_IDLE_HIGH_SAMP_FALLING	= LWSSPIMODE_CPHA |
47 							  LWSSPIMODE_CPOL,
48 
49 	LWS_SPI_TXN_HALF_DUPLEX_DISCRETE	= 0,
50 	/**< separate MISO and MOSI, but only either MISO or MOSI has data at
51 	 * one time... i2c style in SPI */
52 };
53 
54 typedef struct lws_spi_desc {
55 	const uint8_t		*src;
56 	const uint8_t		*data;
57 	uint8_t			*dest;
58 	void			*opaque;
59 	lws_spi_cb_t		completion_cb;
60 	uint16_t		count_cmd;
61 	uint16_t		count_write;
62 	uint16_t		count_read;
63 	uint8_t			txn_type;
64 	uint8_t			channel;
65 } lws_spi_desc_t;
66 
67 typedef struct lws_spi_ops {
68 	int  (*init)(const struct lws_spi_ops *ctx);
69 	int  (*queue)(const struct lws_spi_ops *ctx, const lws_spi_desc_t *desc);
70 	uint8_t	bus_mode;
71 } lws_spi_ops_t;
72 
73 #endif
74