From 807d9e4b9207651d67bb374a60b3a7761842d12b Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Tue, 19 Feb 2019 09:39:16 +1100
Subject: [PATCH] HAL_ChibiOS: added optional polled SPI mode

---
 libraries/AP_HAL_ChibiOS/SPIDevice.cpp | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/libraries/AP_HAL_ChibiOS/SPIDevice.cpp b/libraries/AP_HAL_ChibiOS/SPIDevice.cpp
index 89bb46eea1..85cc0c54b5 100644
--- a/libraries/AP_HAL_ChibiOS/SPIDevice.cpp
+++ b/libraries/AP_HAL_ChibiOS/SPIDevice.cpp
@@ -174,11 +174,19 @@ void SPIDevice::do_transfer(const uint8_t *send, uint8_t *recv, uint32_t len)
         return;
     }
 
+
+#if defined(HAL_SPI_USE_POLLED)
+    for (uint16_t i=0; i<len; i++) {
+        uint8_t ret = spiPolledExchange(spi_devices[device_desc.bus].driver, send?send[i]:0);
+        if (recv) {
+            recv[i] = ret;
+        }
+    }
+#else
     bus.bouncebuffer_setup(send, len, recv, len);
-
     spiExchange(spi_devices[device_desc.bus].driver, len, send, recv);
-
     bus.bouncebuffer_finish(send, recv, len);
+#endif
 
     set_chip_select(old_cs_forced);
 }