opensteno_qmk/drivers/bluetooth/adafruit_ble.cpp
Ryan db41a3426c
Improve Adafruit BLE configuration defines (#14749)
* Improve Adafruit BLE configuration defines

* Formatting
2021-10-08 16:15:20 +01:00

699 lines
21 KiB
C++

#include "adafruit_ble.h"
#include <stdio.h>
#include <stdlib.h>
#include <alloca.h>
#include "debug.h"
#include "timer.h"
#include "action_util.h"
#include "ringbuffer.hpp"
#include <string.h>
#include "spi_master.h"
#include "wait.h"
#include "analog.h"
#include "progmem.h"
// These are the pin assignments for the 32u4 boards.
// You may define them to something else in your config.h
// if yours is wired up differently.
#ifndef ADAFRUIT_BLE_RST_PIN
# define ADAFRUIT_BLE_RST_PIN D4
#endif
#ifndef ADAFRUIT_BLE_CS_PIN
# define ADAFRUIT_BLE_CS_PIN B4
#endif
#ifndef ADAFRUIT_BLE_IRQ_PIN
# define ADAFRUIT_BLE_IRQ_PIN E6
#endif
#ifndef ADAFRUIT_BLE_SCK_DIVISOR
# define ADAFRUIT_BLE_SCK_DIVISOR 2 // 4MHz SCK/8MHz CPU, calculated for Feather 32U4 BLE
#endif
#define SAMPLE_BATTERY
#define ConnectionUpdateInterval 1000 /* milliseconds */
#ifndef BATTERY_LEVEL_PIN
# define BATTERY_LEVEL_PIN B5
#endif
static struct {
bool is_connected;
bool initialized;
bool configured;
#define ProbedEvents 1
#define UsingEvents 2
bool event_flags;
#ifdef SAMPLE_BATTERY
uint16_t last_battery_update;
uint32_t vbat;
#endif
uint16_t last_connection_update;
} state;
// Commands are encoded using SDEP and sent via SPI
// https://github.com/adafruit/Adafruit_BluefruitLE_nRF51/blob/master/SDEP.md
#define SdepMaxPayload 16
struct sdep_msg {
uint8_t type;
uint8_t cmd_low;
uint8_t cmd_high;
struct __attribute__((packed)) {
uint8_t len : 7;
uint8_t more : 1;
};
uint8_t payload[SdepMaxPayload];
} __attribute__((packed));
// The recv latency is relatively high, so when we're hammering keys quickly,
// we want to avoid waiting for the responses in the matrix loop. We maintain
// a short queue for that. Since there is quite a lot of space overhead for
// the AT command representation wrapped up in SDEP, we queue the minimal
// information here.
enum queue_type {
QTKeyReport, // 1-byte modifier + 6-byte key report
QTConsumer, // 16-bit key code
#ifdef MOUSE_ENABLE
QTMouseMove, // 4-byte mouse report
#endif
};
struct queue_item {
enum queue_type queue_type;
uint16_t added;
union __attribute__((packed)) {
struct __attribute__((packed)) {
uint8_t modifier;
uint8_t keys[6];
} key;
uint16_t consumer;
struct __attribute__((packed)) {
int8_t x, y, scroll, pan;
uint8_t buttons;
} mousemove;
};
};
// Items that we wish to send
static RingBuffer<queue_item, 40> send_buf;
// Pending response; while pending, we can't send any more requests.
// This records the time at which we sent the command for which we
// are expecting a response.
static RingBuffer<uint16_t, 2> resp_buf;
static bool process_queue_item(struct queue_item *item, uint16_t timeout);
enum sdep_type {
SdepCommand = 0x10,
SdepResponse = 0x20,
SdepAlert = 0x40,
SdepError = 0x80,
SdepSlaveNotReady = 0xFE, // Try again later
SdepSlaveOverflow = 0xFF, // You read more data than is available
};
enum ble_cmd {
BleInitialize = 0xBEEF,
BleAtWrapper = 0x0A00,
BleUartTx = 0x0A01,
BleUartRx = 0x0A02,
};
enum ble_system_event_bits {
BleSystemConnected = 0,
BleSystemDisconnected = 1,
BleSystemUartRx = 8,
BleSystemMidiRx = 10,
};
#define SdepTimeout 150 /* milliseconds */
#define SdepShortTimeout 10 /* milliseconds */
#define SdepBackOff 25 /* microseconds */
#define BatteryUpdateInterval 10000 /* milliseconds */
static bool at_command(const char *cmd, char *resp, uint16_t resplen, bool verbose, uint16_t timeout = SdepTimeout);
static bool at_command_P(const char *cmd, char *resp, uint16_t resplen, bool verbose = false);
// Send a single SDEP packet
static bool sdep_send_pkt(const struct sdep_msg *msg, uint16_t timeout) {
spi_start(ADAFRUIT_BLE_CS_PIN, false, 0, ADAFRUIT_BLE_SCK_DIVISOR);
uint16_t timerStart = timer_read();
bool success = false;
bool ready = false;
do {
ready = spi_write(msg->type) != SdepSlaveNotReady;
if (ready) {
break;
}
// Release it and let it initialize
spi_stop();
wait_us(SdepBackOff);
spi_start(ADAFRUIT_BLE_CS_PIN, false, 0, ADAFRUIT_BLE_SCK_DIVISOR);
} while (timer_elapsed(timerStart) < timeout);
if (ready) {
// Slave is ready; send the rest of the packet
spi_transmit(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)) + msg->len);
success = true;
}
spi_stop();
return success;
}
static inline void sdep_build_pkt(struct sdep_msg *msg, uint16_t command, const uint8_t *payload, uint8_t len, bool moredata) {
msg->type = SdepCommand;
msg->cmd_low = command & 0xFF;
msg->cmd_high = command >> 8;
msg->len = len;
msg->more = (moredata && len == SdepMaxPayload) ? 1 : 0;
static_assert(sizeof(*msg) == 20, "msg is correctly packed");
memcpy(msg->payload, payload, len);
}
// Read a single SDEP packet
static bool sdep_recv_pkt(struct sdep_msg *msg, uint16_t timeout) {
bool success = false;
uint16_t timerStart = timer_read();
bool ready = false;
do {
ready = readPin(ADAFRUIT_BLE_IRQ_PIN);
if (ready) {
break;
}
wait_us(1);
} while (timer_elapsed(timerStart) < timeout);
if (ready) {
spi_start(ADAFRUIT_BLE_CS_PIN, false, 0, ADAFRUIT_BLE_SCK_DIVISOR);
do {
// Read the command type, waiting for the data to be ready
msg->type = spi_read();
if (msg->type == SdepSlaveNotReady || msg->type == SdepSlaveOverflow) {
// Release it and let it initialize
spi_stop();
wait_us(SdepBackOff);
spi_start(ADAFRUIT_BLE_CS_PIN, false, 0, ADAFRUIT_BLE_SCK_DIVISOR);
continue;
}
// Read the rest of the header
spi_receive(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)));
// and get the payload if there is any
if (msg->len <= SdepMaxPayload) {
spi_receive(msg->payload, msg->len);
}
success = true;
break;
} while (timer_elapsed(timerStart) < timeout);
spi_stop();
}
return success;
}
static void resp_buf_read_one(bool greedy) {
uint16_t last_send;
if (!resp_buf.peek(last_send)) {
return;
}
if (readPin(ADAFRUIT_BLE_IRQ_PIN)) {
struct sdep_msg msg;
again:
if (sdep_recv_pkt(&msg, SdepTimeout)) {
if (!msg.more) {
// We got it; consume this entry
resp_buf.get(last_send);
dprintf("recv latency %dms\n", TIMER_DIFF_16(timer_read(), last_send));
}
if (greedy && resp_buf.peek(last_send) && readPin(ADAFRUIT_BLE_IRQ_PIN)) {
goto again;
}
}
} else if (timer_elapsed(last_send) > SdepTimeout * 2) {
dprintf("waiting_for_result: timeout, resp_buf size %d\n", (int)resp_buf.size());
// Timed out: consume this entry
resp_buf.get(last_send);
}
}
static void send_buf_send_one(uint16_t timeout = SdepTimeout) {
struct queue_item item;
// Don't send anything more until we get an ACK
if (!resp_buf.empty()) {
return;
}
if (!send_buf.peek(item)) {
return;
}
if (process_queue_item(&item, timeout)) {
// commit that peek
send_buf.get(item);
dprintf("send_buf_send_one: have %d remaining\n", (int)send_buf.size());
} else {
dprint("failed to send, will retry\n");
wait_ms(SdepTimeout);
resp_buf_read_one(true);
}
}
static void resp_buf_wait(const char *cmd) {
bool didPrint = false;
while (!resp_buf.empty()) {
if (!didPrint) {
dprintf("wait on buf for %s\n", cmd);
didPrint = true;
}
resp_buf_read_one(true);
}
}
static bool ble_init(void) {
state.initialized = false;
state.configured = false;
state.is_connected = false;
setPinInput(ADAFRUIT_BLE_IRQ_PIN);
spi_init();
// Perform a hardware reset
setPinOutput(ADAFRUIT_BLE_RST_PIN);
writePinHigh(ADAFRUIT_BLE_RST_PIN);
writePinLow(ADAFRUIT_BLE_RST_PIN);
wait_ms(10);
writePinHigh(ADAFRUIT_BLE_RST_PIN);
wait_ms(1000); // Give it a second to initialize
state.initialized = true;
return state.initialized;
}
static inline uint8_t min(uint8_t a, uint8_t b) { return a < b ? a : b; }
static bool read_response(char *resp, uint16_t resplen, bool verbose) {
char *dest = resp;
char *end = dest + resplen;
while (true) {
struct sdep_msg msg;
if (!sdep_recv_pkt(&msg, 2 * SdepTimeout)) {
dprint("sdep_recv_pkt failed\n");
return false;
}
if (msg.type != SdepResponse) {
*resp = 0;
return false;
}
uint8_t len = min(msg.len, end - dest);
if (len > 0) {
memcpy(dest, msg.payload, len);
dest += len;
}
if (!msg.more) {
// No more data is expected!
break;
}
}
// Ensure the response is NUL terminated
*dest = 0;
// "Parse" the result text; we want to snip off the trailing OK or ERROR line
// Rewind past the possible trailing CRLF so that we can strip it
--dest;
while (dest > resp && (dest[0] == '\n' || dest[0] == '\r')) {
*dest = 0;
--dest;
}
// Look back for start of preceeding line
char *last_line = strrchr(resp, '\n');
if (last_line) {
++last_line;
} else {
last_line = resp;
}
bool success = false;
static const char kOK[] PROGMEM = "OK";
success = !strcmp_P(last_line, kOK);
if (verbose || !success) {
dprintf("result: %s\n", resp);
}
return success;
}
static bool at_command(const char *cmd, char *resp, uint16_t resplen, bool verbose, uint16_t timeout) {
const char * end = cmd + strlen(cmd);
struct sdep_msg msg;
if (verbose) {
dprintf("ble send: %s\n", cmd);
}
if (resp) {
// They want to decode the response, so we need to flush and wait
// for all pending I/O to finish before we start this one, so
// that we don't confuse the results
resp_buf_wait(cmd);
*resp = 0;
}
// Fragment the command into a series of SDEP packets
while (end - cmd > SdepMaxPayload) {
sdep_build_pkt(&msg, BleAtWrapper, (uint8_t *)cmd, SdepMaxPayload, true);
if (!sdep_send_pkt(&msg, timeout)) {
return false;
}
cmd += SdepMaxPayload;
}
sdep_build_pkt(&msg, BleAtWrapper, (uint8_t *)cmd, end - cmd, false);
if (!sdep_send_pkt(&msg, timeout)) {
return false;
}
if (resp == NULL) {
uint16_t now = timer_read();
while (!resp_buf.enqueue(now)) {
resp_buf_read_one(false);
}
uint16_t later = timer_read();
if (TIMER_DIFF_16(later, now) > 0) {
dprintf("waited %dms for resp_buf\n", TIMER_DIFF_16(later, now));
}
return true;
}
return read_response(resp, resplen, verbose);
}
bool at_command_P(const char *cmd, char *resp, uint16_t resplen, bool verbose) {
char *cmdbuf = (char *)alloca(strlen_P(cmd) + 1);
strcpy_P(cmdbuf, cmd);
return at_command(cmdbuf, resp, resplen, verbose);
}
bool adafruit_ble_is_connected(void) { return state.is_connected; }
bool adafruit_ble_enable_keyboard(void) {
char resbuf[128];
if (!state.initialized && !ble_init()) {
return false;
}
state.configured = false;
// Disable command echo
static const char kEcho[] PROGMEM = "ATE=0";
// Make the advertised name match the keyboard
static const char kGapDevName[] PROGMEM = "AT+GAPDEVNAME=" STR(PRODUCT);
// Turn on keyboard support
static const char kHidEnOn[] PROGMEM = "AT+BLEHIDEN=1";
// Adjust intervals to improve latency. This causes the "central"
// system (computer/tablet) to poll us every 10-30 ms. We can't
// set a smaller value than 10ms, and 30ms seems to be the natural
// processing time on my macbook. Keeping it constrained to that
// feels reasonable to type to.
static const char kGapIntervals[] PROGMEM = "AT+GAPINTERVALS=10,30,,";
// Reset the device so that it picks up the above changes
static const char kATZ[] PROGMEM = "ATZ";
// Turn down the power level a bit
static const char kPower[] PROGMEM = "AT+BLEPOWERLEVEL=-12";
static PGM_P const configure_commands[] PROGMEM = {
kEcho, kGapIntervals, kGapDevName, kHidEnOn, kPower, kATZ,
};
uint8_t i;
for (i = 0; i < sizeof(configure_commands) / sizeof(configure_commands[0]); ++i) {
PGM_P cmd;
memcpy_P(&cmd, configure_commands + i, sizeof(cmd));
if (!at_command_P(cmd, resbuf, sizeof(resbuf))) {
dprintf("failed BLE command: %S: %s\n", cmd, resbuf);
goto fail;
}
}
state.configured = true;
// Check connection status in a little while; allow the ATZ time
// to kick in.
state.last_connection_update = timer_read();
fail:
return state.configured;
}
static void set_connected(bool connected) {
if (connected != state.is_connected) {
if (connected) {
dprint("BLE connected\n");
} else {
dprint("BLE disconnected\n");
}
state.is_connected = connected;
// TODO: if modifiers are down on the USB interface and
// we cut over to BLE or vice versa, they will remain stuck.
// This feels like a good point to do something like clearing
// the keyboard and/or generating a fake all keys up message.
// However, I've noticed that it takes a couple of seconds
// for macOS to to start recognizing key presses after BLE
// is in the connected state, so I worry that doing that
// here may not be good enough.
}
}
void adafruit_ble_task(void) {
char resbuf[48];
if (!state.configured && !adafruit_ble_enable_keyboard()) {
return;
}
resp_buf_read_one(true);
send_buf_send_one(SdepShortTimeout);
if (resp_buf.empty() && (state.event_flags & UsingEvents) && readPin(ADAFRUIT_BLE_IRQ_PIN)) {
// Must be an event update
if (at_command_P(PSTR("AT+EVENTSTATUS"), resbuf, sizeof(resbuf))) {
uint32_t mask = strtoul(resbuf, NULL, 16);
if (mask & BleSystemConnected) {
set_connected(true);
} else if (mask & BleSystemDisconnected) {
set_connected(false);
}
}
}
if (timer_elapsed(state.last_connection_update) > ConnectionUpdateInterval) {
bool shouldPoll = true;
if (!(state.event_flags & ProbedEvents)) {
// Request notifications about connection status changes.
// This only works in SPIFRIEND firmware > 0.6.7, which is why
// we check for this conditionally here.
// Note that at the time of writing, HID reports only work correctly
// with Apple products on firmware version 0.6.7!
// https://forums.adafruit.com/viewtopic.php?f=8&t=104052
if (at_command_P(PSTR("AT+EVENTENABLE=0x1"), resbuf, sizeof(resbuf))) {
at_command_P(PSTR("AT+EVENTENABLE=0x2"), resbuf, sizeof(resbuf));
state.event_flags |= UsingEvents;
}
state.event_flags |= ProbedEvents;
// leave shouldPoll == true so that we check at least once
// before relying solely on events
} else {
shouldPoll = false;
}
static const char kGetConn[] PROGMEM = "AT+GAPGETCONN";
state.last_connection_update = timer_read();
if (at_command_P(kGetConn, resbuf, sizeof(resbuf))) {
set_connected(atoi(resbuf));
}
}
#ifdef SAMPLE_BATTERY
if (timer_elapsed(state.last_battery_update) > BatteryUpdateInterval && resp_buf.empty()) {
state.last_battery_update = timer_read();
state.vbat = analogReadPin(BATTERY_LEVEL_PIN);
}
#endif
}
static bool process_queue_item(struct queue_item *item, uint16_t timeout) {
char cmdbuf[48];
char fmtbuf[64];
// Arrange to re-check connection after keys have settled
state.last_connection_update = timer_read();
#if 1
if (TIMER_DIFF_16(state.last_connection_update, item->added) > 0) {
dprintf("send latency %dms\n", TIMER_DIFF_16(state.last_connection_update, item->added));
}
#endif
switch (item->queue_type) {
case QTKeyReport:
strcpy_P(fmtbuf, PSTR("AT+BLEKEYBOARDCODE=%02x-00-%02x-%02x-%02x-%02x-%02x-%02x"));
snprintf(cmdbuf, sizeof(cmdbuf), fmtbuf, item->key.modifier, item->key.keys[0], item->key.keys[1], item->key.keys[2], item->key.keys[3], item->key.keys[4], item->key.keys[5]);
return at_command(cmdbuf, NULL, 0, true, timeout);
case QTConsumer:
strcpy_P(fmtbuf, PSTR("AT+BLEHIDCONTROLKEY=0x%04x"));
snprintf(cmdbuf, sizeof(cmdbuf), fmtbuf, item->consumer);
return at_command(cmdbuf, NULL, 0, true, timeout);
#ifdef MOUSE_ENABLE
case QTMouseMove:
strcpy_P(fmtbuf, PSTR("AT+BLEHIDMOUSEMOVE=%d,%d,%d,%d"));
snprintf(cmdbuf, sizeof(cmdbuf), fmtbuf, item->mousemove.x, item->mousemove.y, item->mousemove.scroll, item->mousemove.pan);
if (!at_command(cmdbuf, NULL, 0, true, timeout)) {
return false;
}
strcpy_P(cmdbuf, PSTR("AT+BLEHIDMOUSEBUTTON="));
if (item->mousemove.buttons & MOUSE_BTN1) {
strcat(cmdbuf, "L");
}
if (item->mousemove.buttons & MOUSE_BTN2) {
strcat(cmdbuf, "R");
}
if (item->mousemove.buttons & MOUSE_BTN3) {
strcat(cmdbuf, "M");
}
if (item->mousemove.buttons == 0) {
strcat(cmdbuf, "0");
}
return at_command(cmdbuf, NULL, 0, true, timeout);
#endif
default:
return true;
}
}
void adafruit_ble_send_keys(uint8_t hid_modifier_mask, uint8_t *keys, uint8_t nkeys) {
struct queue_item item;
bool didWait = false;
item.queue_type = QTKeyReport;
item.key.modifier = hid_modifier_mask;
item.added = timer_read();
while (nkeys >= 0) {
item.key.keys[0] = keys[0];
item.key.keys[1] = nkeys >= 1 ? keys[1] : 0;
item.key.keys[2] = nkeys >= 2 ? keys[2] : 0;
item.key.keys[3] = nkeys >= 3 ? keys[3] : 0;
item.key.keys[4] = nkeys >= 4 ? keys[4] : 0;
item.key.keys[5] = nkeys >= 5 ? keys[5] : 0;
if (!send_buf.enqueue(item)) {
if (!didWait) {
dprint("wait for buf space\n");
didWait = true;
}
send_buf_send_one();
continue;
}
if (nkeys <= 6) {
return;
}
nkeys -= 6;
keys += 6;
}
}
void adafruit_ble_send_consumer_key(uint16_t usage) {
struct queue_item item;
item.queue_type = QTConsumer;
item.consumer = usage;
while (!send_buf.enqueue(item)) {
send_buf_send_one();
}
}
#ifdef MOUSE_ENABLE
void adafruit_ble_send_mouse_move(int8_t x, int8_t y, int8_t scroll, int8_t pan, uint8_t buttons) {
struct queue_item item;
item.queue_type = QTMouseMove;
item.mousemove.x = x;
item.mousemove.y = y;
item.mousemove.scroll = scroll;
item.mousemove.pan = pan;
item.mousemove.buttons = buttons;
while (!send_buf.enqueue(item)) {
send_buf_send_one();
}
}
#endif
uint32_t adafruit_ble_read_battery_voltage(void) { return state.vbat; }
bool adafruit_ble_set_mode_leds(bool on) {
if (!state.configured) {
return false;
}
// The "mode" led is the red blinky one
at_command_P(on ? PSTR("AT+HWMODELED=1") : PSTR("AT+HWMODELED=0"), NULL, 0);
// Pin 19 is the blue "connected" LED; turn that off too.
// When turning LEDs back on, don't turn that LED on if we're
// not connected, as that would be confusing.
at_command_P(on && state.is_connected ? PSTR("AT+HWGPIO=19,1") : PSTR("AT+HWGPIO=19,0"), NULL, 0);
return true;
}
// https://learn.adafruit.com/adafruit-feather-32u4-bluefruit-le/ble-generic#at-plus-blepowerlevel
bool adafruit_ble_set_power_level(int8_t level) {
char cmd[46];
if (!state.configured) {
return false;
}
snprintf(cmd, sizeof(cmd), "AT+BLEPOWERLEVEL=%d", level);
return at_command(cmd, NULL, 0, false);
}