xref: /btstack/src/btstack_uart.h (revision 9e104a3cf63fdbd212d138642b65a6147054c37b)
1 /*
2  * Copyright (C) 2021 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
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26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 /**
39  * @title UART
40  *
41  * Common types for UART transports
42  *
43  */
44 
45 #ifndef BTSTACK_UART_H
46 #define BTSTACK_UART_H
47 
48 #include <stdint.h>
49 #include "btstack_config.h"
50 
51 #if defined __cplusplus
52 extern "C" {
53 #endif
54 
55 #define BTSTACK_UART_PARITY_OFF  0
56 #define BTSTACK_UART_PARITY_EVEN 1
57 #define BTSTACK_UART_PARITY_ODD  2
58 
59 typedef enum {
60     // UART active, sleep off
61     BTSTACK_UART_SLEEP_OFF = 0,
62     // used for eHCILL
63     BTSTACK_UART_SLEEP_RTS_HIGH_WAKE_ON_CTS_PULSE,
64     // used for H5 and for eHCILL without support for wake on CTS pulse
65     BTSTACK_UART_SLEEP_RTS_LOW_WAKE_ON_RX_EDGE,
66 
67 } btstack_uart_sleep_mode_t;
68 
69 
70 typedef enum {
71     BTSTACK_UART_SLEEP_MASK_RTS_HIGH_WAKE_ON_CTS_PULSE  = 1 << BTSTACK_UART_SLEEP_RTS_HIGH_WAKE_ON_CTS_PULSE,
72     BTSTACK_UART_SLEEP_MASK_RTS_LOW_WAKE_ON_RX_EDGE     = 1 << BTSTACK_UART_SLEEP_RTS_LOW_WAKE_ON_RX_EDGE
73 } btstack_uart_sleep_mode_mask_t;
74 
75 // parity is mainly used with h5 mode.
76 typedef struct {
77     uint32_t              baudrate;
78     int                   flowcontrol;
79     const char *          device_name;
80     int                   parity;
81 } btstack_uart_config_t;
82 
83 /* API_START */
84 
85 typedef struct {
86     /**
87      * init transport
88      * @param uart_config
89      */
90     int (*init)(const btstack_uart_config_t * uart_config);
91 
92     /**
93      * open transport connection
94      */
95     int (*open)(void);
96 
97     /**
98      * close transport connection
99      */
100     int (*close)(void);
101 
102     /**
103      * set callback for block received. NULL disables callback
104      */
105     void (*set_block_received)(void (*block_handler)(void));
106 
107     /**
108      * set callback for sent. NULL disables callback
109      */
110     void (*set_block_sent)(void (*block_handler)(void));
111 
112     /**
113      * set baudrate
114      */
115     int (*set_baudrate)(uint32_t baudrate);
116 
117     /**
118      * set parity
119      */
120     int  (*set_parity)(int parity);
121 
122     /**
123      * set flowcontrol
124      */
125     int  (*set_flowcontrol)(int flowcontrol);
126 
127     /**
128      * receive block
129      */
130     void (*receive_block)(uint8_t *buffer, uint16_t len);
131 
132     /**
133      * send block
134      */
135     void (*send_block)(const uint8_t *buffer, uint16_t length);
136 
137 
138     /** Support for different Sleep Modes in TI's H4 eHCILL and in H5 - can be set to NULL if not used */
139 
140     /**
141      * query supported wakeup mechanisms
142      * @return supported_sleep_modes mask
143      */
144      int (*get_supported_sleep_modes)(void);
145 
146     /**
147      * set UART sleep mode - allows to turn off UART and it's clocks to save energy
148      * Supported sleep modes:
149      * - off: UART active, RTS low if receive_block was called and block not read yet
150      * - RTS high, wake on CTS: RTS should be high. On CTS pulse, UART gets enabled again and RTS goes to low
151      * - RTS low, wake on RX: data on RX will trigger UART enable, bytes might get lost
152      */
153     void (*set_sleep)(btstack_uart_sleep_mode_t sleep_mode);
154 
155     /**
156      * set wakeup handler - needed to notify hci transport of wakeup requests by Bluetooth controller
157      * Called upon CTS pulse or RX data. See sleep modes.
158      */
159     void (*set_wakeup_handler)(void (*wakeup_handler)(void));
160 
161 
162     /** Support for HCI H5 Transport Mode - can be set to NULL for H4 */
163 
164     /**
165      * H5/SLIP only: set callback for frame received. NULL disables callback
166      */
167     void (*set_frame_received)(void (*frame_handler)(uint16_t frame_size));
168 
169     /**
170      * H5/SLIP only: set callback for frame sent. NULL disables callback
171      */
172     void (*set_frame_sent)(void (*block_handler)(void));
173 
174     /**
175      * H5/SLIP only: receive SLIP frame
176      */
177     void (*receive_frame)(uint8_t *buffer, uint16_t len);
178 
179     /**
180      * H5/SLIP only: send SLIP frame
181      */
182     void (*send_frame)(const uint8_t *buffer, uint16_t length);
183 
184 } btstack_uart_t;
185 
186 /* API_END */
187 
188 // common implementations
189 const btstack_uart_t * btstack_uart_posix_instance(void);
190 
191 #if defined __cplusplus
192 }
193 #endif
194 
195 #endif
196