nrf/nimble: Use soft timer for hci polling.

Signed-off-by: Andrew Leech <andrew@alelec.net>

ports/nrf/mpbthciport.c

@@ -29,53 +29,92 @@
 #include "py/runtime.h"
 #include "py/mperrno.h"
 #include "py/mphal.h"
+#include "shared/runtime/softtimer.h"
 
 #if MICROPY_PY_BLUETOOTH
 
 #define DEBUG_printf(...) // mp_printf(&mp_plat_print, "mpbthciport.c: " __VA_ARGS__)
 
 #include "mpbthciport.h"
-#include "drivers/ticker.h"
+// #include "drivers/ticker.h"
 
-#define BLUETOOTH_TICKER_SLOT 0
+// #define BLUETOOTH_TICKER_SLOT 0
+
+// Soft timer and scheduling node for scheduling a HCI poll.
+static soft_timer_entry_t mp_bluetooth_hci_soft_timer;
+static mp_sched_node_t mp_bluetooth_hci_sched_node;
+
+
+// This is called by soft_timer and executes at PendSV level.
+static void mp_bluetooth_hci_soft_timer_callback(soft_timer_entry_t *self) {
+    mp_bluetooth_hci_poll_now();
+}
 
 // // Prevent double-enqueuing of the scheduled task.
-static volatile bool events_task_is_scheduled = false;
+// static volatile bool events_task_is_scheduled = false;
 
 void mp_bluetooth_hci_init(void) {
     /* Start regular background task to handle events */
-    events_task_is_scheduled = false;
-    set_ticker_callback(BLUETOOTH_TICKER_SLOT, mp_bluetooth_hci_poll_now, 0);
+    // events_task_is_scheduled = false;
+    // set_ticker_callback(BLUETOOTH_TICKER_SLOT, mp_bluetooth_hci_poll_now, 0);
+    soft_timer_static_init(
+        &mp_bluetooth_hci_soft_timer,
+        SOFT_TIMER_MODE_ONE_SHOT,
+        0,
+        mp_bluetooth_hci_soft_timer_callback
+        );
 }
 
 void mp_bluetooth_hci_deinit(void) {
-    clear_ticker_callback(BLUETOOTH_TICKER_SLOT);
-    events_task_is_scheduled = false;
+    // clear_ticker_callback(BLUETOOTH_TICKER_SLOT);
+    //   events_task_is_scheduled = false;
+    soft_timer_remove(&mp_bluetooth_hci_soft_timer);
+
+}
+
+// // For synchronous mode, we run all BLE stack code inside a scheduled task.
+// // This task is scheduled periodically via a timer.
+// static mp_obj_t run_events_scheduled_task(mp_obj_t none_in) {
+//     (void)none_in;
+//     events_task_is_scheduled = false;
+//     mp_bluetooth_hci_poll();
+//     return mp_const_none;
+// }
+// static MP_DEFINE_CONST_FUN_OBJ_1(run_events_scheduled_task_obj, run_events_scheduled_task);
+
+
+// // Called periodically (ticker) to request that processing happens in the scheduler.
+// int32_t mp_bluetooth_hci_poll_now(void) {
+//     // Return interval (128ms in 16us ticks) until next callback run
+//     uint32_t next_tick = 128000 / 16;
+//     if (!events_task_is_scheduled) {
+//         events_task_is_scheduled = mp_sched_schedule(MP_OBJ_FROM_PTR(&run_events_scheduled_task_obj), mp_const_none);
+//         if (!events_task_is_scheduled) {
+//             // The schedule queue is full, set callback to try again soon (5ms).
+//             next_tick = 5000 / 16;
+//         }
+//     }
+//     return next_tick;
+// }
+
+// static void mp_bluetooth_hci_start_polling(void) {
+//     mp_bluetooth_hci_poll_now();
+// }
+
+void mp_bluetooth_hci_poll_in_ms(uint32_t ms) {
+    soft_timer_reinsert(&mp_bluetooth_hci_soft_timer, ms);
 }
 
 // For synchronous mode, we run all BLE stack code inside a scheduled task.
-// This task is scheduled periodically via a timer.
-static mp_obj_t run_events_scheduled_task(mp_obj_t none_in) {
-    (void)none_in;
-    events_task_is_scheduled = false;
+static void run_events_scheduled_task(mp_sched_node_t *node) {
+    // This will process all buffered HCI UART data, and run any callouts or events.
     mp_bluetooth_hci_poll();
-    return mp_const_none;
 }
-static MP_DEFINE_CONST_FUN_OBJ_1(run_events_scheduled_task_obj, run_events_scheduled_task);
 
-
-// Called periodically (ticker) to request that processing happens in the scheduler.
-int32_t mp_bluetooth_hci_poll_now(void) {
-    // Return interval (128ms in 16us ticks) until next callback run
-    uint32_t next_tick = 128000 / 16;
-    if (!events_task_is_scheduled) {
-        events_task_is_scheduled = mp_sched_schedule(MP_OBJ_FROM_PTR(&run_events_scheduled_task_obj), mp_const_none);
-        if (!events_task_is_scheduled) {
-            // The schedule queue is full, set callback to try again soon (5ms).
-            next_tick = 5000 / 16;
-        }
-    }
-    return next_tick;
+// Called periodically (systick) or directly (e.g. UART RX IRQ) in order to
+// request that processing happens ASAP in the scheduler.
+void mp_bluetooth_hci_poll_now(void) {
+    mp_sched_schedule_node(&mp_bluetooth_hci_sched_node, run_events_scheduled_task);
 }
 
 #endif // MICROPY_PY_BLUETOOTH

ports/nrf/mpbthciport.h

@@ -30,8 +30,9 @@
 void mp_bluetooth_hci_init(void);
 void mp_bluetooth_hci_deinit(void);
 
-// Poll the HCI now.
-int32_t mp_bluetooth_hci_poll_now(void);
+// Poll the HCI now, or after a certain timeout.
+void mp_bluetooth_hci_poll_now(void);
+void mp_bluetooth_hci_poll_in_ms(uint32_t ms);
 
 // Must be provided by the stack bindings (e.g. mpnimbleport.c or mpbtstackport.c).
 // Request new HCI data and pass to the stack, and run pending events/callouts.

ports/nrf/mpnimbleport.c

@@ -61,10 +61,14 @@ void mp_bluetooth_hci_controller_init(void) {
 
     // Tell the host that we are ready to receive packets
     ble_ll_hci_send_noop();
+
+    // Start polling for date.
+    mp_bluetooth_hci_poll_now();
 }
 
 void mp_bluetooth_hci_controller_deinit(void) {
     mp_bluetooth_hci_deinit();
+
 }
 
 // The global BLE controller LL data object
@@ -92,6 +96,11 @@ void mp_bluetooth_hci_poll(void) {
         // Run any remaining events.
         mp_bluetooth_nimble_os_eventq_run_all();
     }
+    if (mp_bluetooth_nimble_ble_state != MP_BLUETOOTH_NIMBLE_BLE_STATE_OFF) {
+        // Call this function again in 128ms to check for new events.
+        // TODO: improve this by only calling back when needed.
+        mp_bluetooth_hci_poll_in_ms(128);
+    }
 }
 
 // --- Port-specific helpers for the generic NimBLE bindings. -----------------
@@ -123,6 +132,7 @@ static func nrf_ble_isr_rtc0 = NULL;
 void RADIO_IRQHandler(void) {
     if (nrf_ble_isr_phy != NULL) {
         nrf_ble_isr_phy();
+        mp_bluetooth_hci_poll_in_ms(5);
     }
 }