From 91fb9e7888d5babb6e52427eeb67fcd052a30a10 Mon Sep 17 00:00:00 2001
From: Andrew Leech <andrew.leech@planetinnovation.com.au>
Date: Wed, 25 May 2022 12:41:51 +1000
Subject: [PATCH] extmod/nimble: Add support for reading whole HCI UART
 packets.

This can improve efficiency for Bluetooth systems that already process
whole packets at the lower layers.
---
 extmod/mpbthci.h             | 11 ++++++++++-
 extmod/nimble/hal/hal_uart.c | 27 ++++++++++++++++++++++-----
 2 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/extmod/mpbthci.h b/extmod/mpbthci.h
index 6997238033..c10f99c3df 100644
--- a/extmod/mpbthci.h
+++ b/extmod/mpbthci.h
@@ -27,6 +27,9 @@
 #ifndef MICROPY_INCLUDED_EXTMOD_MPBTHCI_H
 #define MICROPY_INCLUDED_EXTMOD_MPBTHCI_H
 
+#define MICROPY_PY_BLUETOOTH_HCI_READ_MODE_BYTE  (0)
+#define MICROPY_PY_BLUETOOTH_HCI_READ_MODE_PACKET  (1)
+
 // --- Optionally can be implemented by the driver. ---------------------------
 
 // Start/stop the HCI controller.
@@ -46,7 +49,13 @@ int mp_bluetooth_hci_uart_init(uint32_t port, uint32_t baudrate);
 int mp_bluetooth_hci_uart_deinit(void);
 int mp_bluetooth_hci_uart_set_baudrate(uint32_t baudrate);
 int mp_bluetooth_hci_uart_any(void);
-int mp_bluetooth_hci_uart_readchar(void);
 int mp_bluetooth_hci_uart_write(const uint8_t *buf, size_t len);
 
+// Used for mode: MICROPY_PY_BLUETOOTH_HCI_READ_MODE_BYTE
+int mp_bluetooth_hci_uart_readchar(void);
+
+// Used for mode: MICROPY_PY_BLUETOOTH_HCI_READ_MODE_PACKET
+typedef void (*mp_bluetooth_hci_uart_readchar_t)(uint8_t chr);
+int mp_bluetooth_hci_uart_readpacket(mp_bluetooth_hci_uart_readchar_t handler);
+
 #endif // MICROPY_INCLUDED_EXTMOD_MPBTHCI_H
diff --git a/extmod/nimble/hal/hal_uart.c b/extmod/nimble/hal/hal_uart.c
index 84a964fde9..6c17da0860 100644
--- a/extmod/nimble/hal/hal_uart.c
+++ b/extmod/nimble/hal/hal_uart.c
@@ -34,6 +34,10 @@
 
 #if MICROPY_PY_BLUETOOTH && MICROPY_BLUETOOTH_NIMBLE
 
+#ifndef MICROPY_PY_BLUETOOTH_HCI_READ_MODE
+#define MICROPY_PY_BLUETOOTH_HCI_READ_MODE MICROPY_PY_BLUETOOTH_HCI_READ_MODE_BYTE
+#endif
+
 #define HCI_TRACE (0)
 
 static hal_uart_tx_cb_t hal_uart_tx_cb;
@@ -86,15 +90,28 @@ int hal_uart_close(uint32_t port) {
     return 0; // success
 }
 
+STATIC void mp_bluetooth_hci_uart_char_cb(uint8_t chr) {
+    #if HCI_TRACE
+    printf("> %02x\n", chr);
+    #endif
+    hal_uart_rx_cb(hal_uart_rx_arg, chr);
+}
+
 void mp_bluetooth_nimble_hci_uart_process(bool run_events) {
     bool host_wake = mp_bluetooth_hci_controller_woken();
 
-    int chr;
-    while ((chr = mp_bluetooth_hci_uart_readchar()) >= 0) {
-        #if HCI_TRACE
-        printf("> %02x\n", chr);
+    for (;;) {
+        #if MICROPY_PY_BLUETOOTH_HCI_READ_MODE == MICROPY_PY_BLUETOOTH_HCI_READ_MODE_BYTE
+        int chr = mp_bluetooth_hci_uart_readchar();
+        if (chr < 0) {
+            break;
+        }
+        mp_bluetooth_hci_uart_char_cb(chr);
+        #elif MICROPY_PY_BLUETOOTH_HCI_READ_MODE == MICROPY_PY_BLUETOOTH_HCI_READ_MODE_PACKET
+        if (mp_bluetooth_hci_uart_readpacket(mp_bluetooth_hci_uart_char_cb) < 0) {
+            break;
+        }
         #endif
-        hal_uart_rx_cb(hal_uart_rx_arg, chr);
 
         // Incoming data may result in events being enqueued. If we're in
         // scheduler context then we can run those events immediately.