From d50f43e9f5b3a56d2ac7f65af48fd18fcd7105d5 Mon Sep 17 00:00:00 2001
From: Thomas Eichinger <thomas.eichinger1@gmail.com>
Date: Thu, 17 Jul 2014 15:42:30 +0200
Subject: [PATCH] at86rf231: introduce variable to keep internal driver state

The at86rf231 radio transceiver provides one IRQ (TRX_END) signaling
end of transmission or reception but no way to distinguish between
these.
---
 drivers/at86rf231/at86rf231.c    | 16 +++++++++++++++-
 drivers/at86rf231/at86rf231_tx.c | 10 ++++++++++
 drivers/include/at86rf231.h      | 13 +++++++++++++
 3 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/drivers/at86rf231/at86rf231.c b/drivers/at86rf231/at86rf231.c
index 275ec6acc7..32eb5623e1 100644
--- a/drivers/at86rf231/at86rf231.c
+++ b/drivers/at86rf231/at86rf231.c
@@ -18,6 +18,7 @@
  * @brief       Driver implementation for at86rf231 chip
  *
  * @author      Alaeddine Weslati <alaeddine.weslati@inria.fr>
+ * @author      Thomas Eichinger <thomas.eichinger@fu-berlin.de>
  *
  * @}
  */
@@ -34,6 +35,8 @@ static uint8_t  radio_channel;
 static uint16_t radio_address;
 static uint64_t radio_address_long;
 
+uint8_t  driver_state;
+
 void at86rf231_init(kernel_pid_t tpid)
 {
     transceiver_pid = tpid;
@@ -103,7 +106,18 @@ void at86rf231_switch_to_rx(void)
 
 void at86rf231_rx_irq(void)
 {
-    at86rf231_rx_handler();
+    /* check if we are in sending state */
+    if (driver_state == AT_DRIVER_STATE_SENDING) {
+        /* Read IRQ to clear it */
+        at86rf231_reg_read(AT86RF231_REG__IRQ_STATUS);
+        /* clear internal state */
+        driver_state = AT_DRIVER_STATE_DEFAULT;
+        return;
+    }
+    else {
+        /* handle receive */
+        at86rf231_rx_handler();
+    }
 }
 
 radio_address_t at86rf231_set_address(radio_address_t address)
diff --git a/drivers/at86rf231/at86rf231_tx.c b/drivers/at86rf231/at86rf231_tx.c
index 66053fd506..6976e8dcae 100644
--- a/drivers/at86rf231/at86rf231_tx.c
+++ b/drivers/at86rf231/at86rf231_tx.c
@@ -10,7 +10,11 @@
 #include "at86rf231_arch.h"
 #include "at86rf231_spi.h"
 
+#define ENABLE_DEBUG (0)
+#include "debug.h"
+
 static void at86rf231_xmit(uint8_t *data, radio_packet_length_t length);
+
 static void at86rf231_gen_pkt(uint8_t *buf, at86rf231_packet_t *packet);
 
 static uint8_t sequenz_nr;
@@ -87,11 +91,17 @@ static void at86rf231_xmit(uint8_t *data, radio_packet_length_t length)
     }
     while ((status & AT86RF231_TRX_STATUS_MASK__TRX_STATUS) != AT86RF231_TRX_STATUS__PLL_ON);
 
+    /* radio driver state: sending */
+    /* will be freed in at86rf231_rx_irq when TRX_END interrupt occurs */
+    driver_state = AT_DRIVER_STATE_SENDING;
+
     // copy the packet to the radio FIFO
     at86rf231_write_fifo(data, length);
+    DEBUG("Wrote to FIFO\n");
 
     // Start TX
     at86rf231_reg_write(AT86RF231_REG__TRX_STATE, AT86RF231_TRX_STATE__TX_START);
+    DEBUG("Started TX\n");
 }
 
 /**
diff --git a/drivers/include/at86rf231.h b/drivers/include/at86rf231.h
index e019d6b73d..eab048373e 100644
--- a/drivers/include/at86rf231.h
+++ b/drivers/include/at86rf231.h
@@ -31,6 +31,19 @@ typedef struct __attribute__((packed))
 }
 at86rf231_packet_t;
 
+extern int transceiver_pid;
+
+#define AT_DRIVER_STATE_DEFAULT     (0)
+#define AT_DRIVER_STATE_SENDING     (1)
+
+/**
+ * @brief To keep state inside of at86rf231 driver
+ * @details This variable is used to determine if a TRX_END IRQ from
+ *          the radio transceiver has to be interpreted as end of
+ *          sending or reception.
+ */
+extern uint8_t driver_state;
+
 void at86rf231_init(kernel_pid_t tpid);
 //void at86rf231_reset(void);
 void at86rf231_rx(void);