From c97b49f55b0fcce0ce59478b0018090b1271b132 Mon Sep 17 00:00:00 2001
From: Martino Facchin <m.facchin@arduino.cc>
Date: Mon, 9 Dec 2024 16:18:38 +0100
Subject: [PATCH] SPI: provide a hook to set the minimum SPI frequency

On Giga, the system will complain loudly if the frequency selected is too low
```<err> spi_ll_stm32: Unsupported frequency 400000Hz, max 120000000Hz, min 937500Hz```
Let's try to keep this at minimum or change when we'll be able to grab the same infor from a macro/API provided by zephyr
---
 libraries/SPI/SPI.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libraries/SPI/SPI.cpp b/libraries/SPI/SPI.cpp
index cfea9af7..f55c17c2 100644
--- a/libraries/SPI/SPI.cpp
+++ b/libraries/SPI/SPI.cpp
@@ -79,9 +79,13 @@ void arduino::ZephyrSPI::usingInterrupt(int interruptNumber) {
 void arduino::ZephyrSPI::notUsingInterrupt(int interruptNumber) {
 }
 
+#ifndef SPI_MIN_CLOCK_FEQUENCY
+#define SPI_MIN_CLOCK_FEQUENCY 1000000
+#endif
+
 void arduino::ZephyrSPI::beginTransaction(SPISettings settings) {
   memset(&config, 0, sizeof(config));
-  config.frequency = settings.getClockFreq();
+  config.frequency = settings.getClockFreq() > SPI_MIN_CLOCK_FEQUENCY ? settings.getClockFreq() : SPI_MIN_CLOCK_FEQUENCY;
   auto mode = SPI_MODE_CPOL | SPI_MODE_CPHA;
   switch (settings.getDataMode()) {
     case SPI_MODE0: