feat: ability to define HCI SPI transport configuration

Signed-off-by: Frederic Pillon <frederic.pillon@st.com>

Author: fpistm

README.md

@@ -25,12 +25,68 @@ For more information about ArduinoBLE library please visit the official web page
 https://www.arduino.cc/en/Reference/ArduinoBLE
 
 # Configuration
+
+### STM32WB
+
 STM32Cube_WPAN has several configuration options, which are set in the `app_conf.h`.
 This package has a default configuration named `app_conf_default.h`.
 The user can include the file `app_conf_custom.h` to customize the BLE application.
 Options wrapped in `#ifndef`, `#endif` in `app_conf_default.h` can be overwritten.
 Additional options can be added.
 
+### Shield
+
+The user can include the file `ble_spi_conf.h` to define which shield and configuration to use from the following list:
+
+ * [X-NUCLEO-IDB05A2](https://www.st.com/en/ecosystems/x-nucleo-idb05a2.html)
+    * `IDB05A2_SPI_CLOCK_D3`: SPI clock on D3
+    * `IDB05A2_SPI_CLOCK_D13` SPI clock on D13
+ * [X-NUCLEO-IDB05A1](https://www.st.com/en/ecosystems/x-nucleo-idb05a1.html)
+    * `IDB05A1_SPI_CLOCK_D3`: SPI clock on D3
+    * `IDB05A1_SPI_CLOCK_D13`: SPI clock on D13
+ * [X-NUCLEO-BNRG2A1](https://www.st.com/en/ecosystems/x-nucleo-bnrg2a1.html)
+    * `BNRG2A1_CLOCK_D3`: SPI clock on D3
+    * `BNRG2A1_CLOCK_D13`: SPI clock on D13
+ * `CUSTOM_BLE_SPI`: define a custom configuration, it requires below definition:
+    * `BLE_SPI_MISO`: SPI MISO pin
+    * `BLE_SPI_MOSI`: SPI MOSI pin
+    * `BLE_SPI_CLK`: SPI CLocK pin
+    * `BLE_SPI_CS`: SPI Chip Select pin
+    * `BLE_SPI_IRQ`: SPI IRQ pin
+    * `BLE_SPI_FREQ`: SPI bus frequency
+    * `BLE_SPI_MODE`: can be one of the below `SPIMode`:
+      * `SPI_MODE0`
+      * `SPI_MODE1`
+      * `SPI_MODE2`
+      * `SPI_MODE0`
+    * `BLE_CHIP_TYPE`: can be one of the below `BLEChip_t`:
+      * `SPBTLE_RF`
+      * `SPBTLE_1S`
+      * `BLUENRG_M2SP`
+      * `BLUENRG_M0`
+      * `BLUENRG_LP`
+    * `BLE_RESET`: BLE reset pin
+
+#### Examples
+
+To use the [X-NUCLEO-IDB05A2](https://www.st.com/en/ecosystems/x-nucleo-idb05a2.html) with SPI clock on D3, define in `ble_spi_conf.h`:
+```C
+#define IDB05A2_SPI_CLOCK_D3
+```
+This is equivalent to the below configuration using the `CUSTOM_BLE_SPI`:
+```C
+#define CUSTOM_BLE_SPI
+#define BLE_SPI_MISO    D12
+#define BLE_SPI_MOSI    D11
+#define BLE_SPI_CLK     D3
+#define BLE_SPI_CS      A1
+#define BLE_SPI_IRQ     A0
+#define BLE_SPI_FREQ    8000000
+#define BLE_SPI_MODE    SPI_MODE0
+#define BLE_CHIP_TYPE   BLUENRG_M0
+#define BLE_RESET       D7
+```
+
 ## License
 
 ```

src/utility/HCISpiTransport.cpp

@@ -21,6 +21,10 @@
 
 #include "HCISpiTransport.h"
 
+#if __has_include("ble_spi_conf.h")
+  #include "ble_spi_conf.h"
+#endif
+
 #if defined(ARDUINO_STEVAL_MKBOXPRO)
 /* STEVAL-MKBOXPRO */
 SPIClass SpiHCI(PA7, PA6, PA5);
@@ -57,6 +61,9 @@ HCISpiTransportClass HCISpiTransport(SpiHCI, BLUENRG_M2SP, A1, A0, D7, 1000000,
 /* Shield BNRG2A1 with SPI clock on D13 */
 #define SpiHCI SPI
 HCISpiTransportClass HCISpiTransport(SpiHCI, BLUENRG_M2SP, A1, A0, D7, 1000000, SPI_MODE1);
+#elif defined(CUSTOM_BLE_SPI)
+SPIClass SpiHCI(BLE_SPI_MOSI, BLE_SPI_MISO, BLE_SPI_CLK);
+HCISpiTransportClass HCISpiTransport(SpiHCI, BLE_CHIP_TYPE, BLE_SPI_CS, BLE_SPI_IRQ, BLE_RESET, BLE_SPI_FREQ, BLE_SPI_MODE);
 #else
 #error "Unsupported board or shield selected!"
 #endif