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-rw-r--r--drivers/bluetooth/adafruit_ble.cpp701
1 files changed, 701 insertions, 0 deletions
diff --git a/drivers/bluetooth/adafruit_ble.cpp b/drivers/bluetooth/adafruit_ble.cpp
new file mode 100644
index 0000000000..3f2cc35734
--- /dev/null
+++ b/drivers/bluetooth/adafruit_ble.cpp
@@ -0,0 +1,701 @@
+#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 AdafruitBleResetPin
+# define AdafruitBleResetPin D4
+#endif
+
+#ifndef AdafruitBleCSPin
+# define AdafruitBleCSPin B4
+#endif
+
+#ifndef AdafruitBleIRQPin
+# define AdafruitBleIRQPin E6
+#endif
+
+#ifndef AdafruitBleSpiClockSpeed
+# define AdafruitBleSpiClockSpeed 4000000UL // SCK frequency
+#endif
+
+#define SCK_DIVISOR (F_CPU / AdafruitBleSpiClockSpeed)
+
+#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(AdafruitBleCSPin, false, 0, 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(AdafruitBleCSPin, false, 0, 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(AdafruitBleIRQPin);
+ if (ready) {
+ break;
+ }
+ wait_us(1);
+ } while (timer_elapsed(timerStart) < timeout);
+
+ if (ready) {
+ spi_start(AdafruitBleCSPin, false, 0, 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(AdafruitBleCSPin, false, 0, 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(AdafruitBleIRQPin)) {
+ 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(AdafruitBleIRQPin)) {
+ 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(AdafruitBleIRQPin);
+
+ spi_init();
+
+ // Perform a hardware reset
+ setPinOutput(AdafruitBleResetPin);
+ writePinHigh(AdafruitBleResetPin);
+ writePinLow(AdafruitBleResetPin);
+ wait_ms(10);
+ writePinHigh(AdafruitBleResetPin);
+
+ 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(AdafruitBleIRQPin)) {
+ // 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);
+}