src/main/drivers/serial.h

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #pragma once
  22
  23 #include "drivers/io.h"
  24 #include "pg/pg.h"
  25
  26 typedef enum {
  27     MODE_RX = 1 << 0,
  28     MODE_TX = 1 << 1,
  29     MODE_RXTX = MODE_RX | MODE_TX
  30 } portMode_e;
  31
  32 typedef enum {
  33     SERIAL_NOT_INVERTED  = 0 << 0,
  34     SERIAL_INVERTED      = 1 << 0,
  35     SERIAL_STOPBITS_1    = 0 << 1,
  36     SERIAL_STOPBITS_2    = 1 << 1,
  37     SERIAL_PARITY_NO     = 0 << 2,
  38     SERIAL_PARITY_EVEN   = 1 << 2,
  39     SERIAL_UNIDIR        = 0 << 3,
  40     SERIAL_BIDIR         = 1 << 3,
  41
  42     /*
  43      * Note on SERIAL_BIDIR_PP
  44      * With SERIAL_BIDIR_PP, the very first start bit of back-to-back bytes
  45      * is lost and the first data byte will be lost by a framing error.
  46      * To ensure the first start bit to be sent, prepend a zero byte (0x00)
  47      * to actual data bytes.
  48      */
  49     SERIAL_BIDIR_OD        = 0 << 4,
  50     SERIAL_BIDIR_PP        = 1 << 4,
  51     SERIAL_BIDIR_NOPULL    = 1 << 5, // disable pulls in BIDIR RX mode
  52 } portOptions_e;
  53
  54 // Define known line control states which may be passed up by underlying serial driver callback
  55 #define CTRL_LINE_STATE_DTR (1 << 0)
  56 #define CTRL_LINE_STATE_RTS (1 << 1)
  57
  58 typedef void (*serialReceiveCallbackPtr)(uint16_t data, void *rxCallbackData);   // used by serial drivers to return frames to app
  59
  60 typedef struct serialPort_s {
  61
  62     const struct serialPortVTable *vTable;
  63
  64     portMode_e mode;
  65     portOptions_e options;
  66
  67     uint32_t baudRate;
  68
  69     uint32_t rxBufferSize;
  70     uint32_t txBufferSize;
  71     volatile uint8_t *rxBuffer;
  72     volatile uint8_t *txBuffer;
  73     uint32_t rxBufferHead;
  74     uint32_t rxBufferTail;
  75     uint32_t txBufferHead;
  76     uint32_t txBufferTail;
  77
  78     serialReceiveCallbackPtr rxCallback;
  79     void *rxCallbackData;
  80
  81     uint8_t identifier;
  82 } serialPort_t;
  83
  84 #if defined(USE_SOFTSERIAL1) || defined(USE_SOFTSERIAL2)
  85 # ifdef USE_SOFTSERIAL2
  86 #  define SERIAL_PORT_MAX_INDEX (RESOURCE_SOFT_OFFSET + 2)
  87 # else
  88 #  define SERIAL_PORT_MAX_INDEX (RESOURCE_SOFT_OFFSET + 1)
  89 # endif
  90 #else
  91 # define SERIAL_PORT_MAX_INDEX RESOURCE_SOFT_OFFSET
  92 #endif
  93
  94 typedef struct serialPinConfig_s {
  95     ioTag_t ioTagTx[SERIAL_PORT_MAX_INDEX];
  96     ioTag_t ioTagRx[SERIAL_PORT_MAX_INDEX];
  97     ioTag_t ioTagInverter[SERIAL_PORT_MAX_INDEX];
  98 } serialPinConfig_t;
  99
 100 PG_DECLARE(serialPinConfig_t, serialPinConfig);
 101
 102 struct serialPortVTable {
 103     void (*serialWrite)(serialPort_t *instance, uint8_t ch);
 104
 105     uint32_t (*serialTotalRxWaiting)(const serialPort_t *instance);
 106     uint32_t (*serialTotalTxFree)(const serialPort_t *instance);
 107
 108     uint8_t (*serialRead)(serialPort_t *instance);
 109
 110     // Specified baud rate may not be allowed by an implementation, use serialGetBaudRate to determine actual baud rate in use.
 111     void (*serialSetBaudRate)(serialPort_t *instance, uint32_t baudRate);
 112
 113     bool (*isSerialTransmitBufferEmpty)(const serialPort_t *instance);
 114
 115     void (*setMode)(serialPort_t *instance, portMode_e mode);
 116     void (*setCtrlLineStateCb)(serialPort_t *instance, void (*cb)(void *instance, uint16_t ctrlLineState), void *context);
 117     void (*setBaudRateCb)(serialPort_t *instance, void (*cb)(serialPort_t *context, uint32_t baud), serialPort_t *context);
 118
 119     void (*writeBuf)(serialPort_t *instance, const void *data, int count);
 120     // Optional functions used to buffer large writes.
 121     void (*beginWrite)(serialPort_t *instance);
 122     void (*endWrite)(serialPort_t *instance);
 123 };
 124
 125 void serialWrite(serialPort_t *instance, uint8_t ch);
 126 uint32_t serialRxBytesWaiting(const serialPort_t *instance);
 127 uint32_t serialTxBytesFree(const serialPort_t *instance);
 128 void serialWriteBuf(serialPort_t *instance, const uint8_t *data, int count);
 129 uint8_t serialRead(serialPort_t *instance);
 130 void serialSetBaudRate(serialPort_t *instance, uint32_t baudRate);
 131 void serialSetMode(serialPort_t *instance, portMode_e mode);
 132 void serialSetCtrlLineStateCb(serialPort_t *instance, void (*cb)(void *context, uint16_t ctrlLineState), void *context);
 133 void serialSetBaudRateCb(serialPort_t *instance, void (*cb)(serialPort_t *context, uint32_t baud), serialPort_t *context);
 134 bool isSerialTransmitBufferEmpty(const serialPort_t *instance);
 135 void serialPrint(serialPort_t *instance, const char *str);
 136 uint32_t serialGetBaudRate(serialPort_t *instance);
 137
 138 // A shim that adapts the bufWriter API to the serialWriteBuf() API.
 139 void serialWriteBufShim(void *instance, const uint8_t *data, int count);
 140 void serialBeginWrite(serialPort_t *instance);
 141 void serialEndWrite(serialPort_t *instance);