[Bug] Updated Cirque Pinnacle SPI driver to read data correctly (#17074)

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/sensors/cirque_pinnacle_spi.c b/drivers/sensors/cirque_pinnacle_spi.c
index e00e73eb8c..34c77df07b 100644
--- a/drivers/sensors/cirque_pinnacle_spi.c
+++ b/drivers/sensors/cirque_pinnacle_spi.c
@@ -7,6 +7,7 @@
 // Masks for Cirque Register Access Protocol (RAP)
 #define WRITE_MASK 0x80
 #define READ_MASK 0xA0
+#define FILLER_BYTE 0xFC
 
 extern bool touchpad_init;
 
@@ -16,11 +17,11 @@ void RAP_ReadBytes(uint8_t address, uint8_t* data, uint8_t count) {
     uint8_t cmdByte = READ_MASK | address; // Form the READ command byte
     if (touchpad_init) {
         if (spi_start(CIRQUE_PINNACLE_SPI_CS_PIN, CIRQUE_PINNACLE_SPI_LSBFIRST, CIRQUE_PINNACLE_SPI_MODE, CIRQUE_PINNACLE_SPI_DIVISOR)) {
-            spi_write(cmdByte);
-            spi_read(); // filler
-            spi_read(); // filler
+            spi_write(cmdByte);     // write command byte, receive filler
+            spi_write(FILLER_BYTE); // write & receive filler
+            spi_write(FILLER_BYTE); // write & receive filler
             for (uint8_t i = 0; i < count; i++) {
-                data[i] = spi_read(); // each sepsequent read gets another register's contents
+                data[i] = spi_write(FILLER_BYTE); // write filler, receive data on the third filler send
             }
         } else {
 #ifdef CONSOLE_ENABLE