From 17ad0fc5a72818b2c50d57f1c102d94d3d77fea1 Mon Sep 17 00:00:00 2001
From: Akshai M <akshai.m@fu-berlin.de>
Date: Wed, 7 Jul 2021 13:38:23 +0200
Subject: [PATCH] driver/sx126x : Add set_rf_mode interface

---
 drivers/include/sx126x.h               | 24 ++++++++++++++++++++++--
 drivers/sx126x/include/sx126x_params.h | 14 +++++++++++++-
 drivers/sx126x/sx126x_netdev.c         | 11 +++++++++++
 3 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/drivers/include/sx126x.h b/drivers/include/sx126x.h
index 0221d92272..78d0eba604 100644
--- a/drivers/include/sx126x.h
+++ b/drivers/include/sx126x.h
@@ -34,6 +34,20 @@
 extern "C" {
 #endif
 
+/**
+ * * @note Forward declaration of the SX126x device descriptor
+ */
+typedef struct sx126x sx126x_t;
+
+/**
+ * @brief RF switch states
+ */
+typedef enum {
+    SX126X_RF_MODE_RX,
+    SX126X_RF_MODE_TX_LPA,
+    SX126X_RF_MODE_TX_HPA,
+} sx126x_rf_mode_t;
+
 /**
  * @brief   Whether there's only one variant of this driver at compile time or
  * not.
@@ -76,12 +90,18 @@ typedef struct {
     gpio_t dio1_pin;                    /**< Dio1 pin */
     sx126x_reg_mod_t regulator;         /**< Power regulator mode */
     sx126x_type_t type;                 /**< Variant of sx126x */
+#if IS_USED(MODULE_SX126X_RF_SWITCH)
+    /**
+     * @ brief  Interface to set RF switch parameters
+     */
+    void(*set_rf_mode)(sx126x_t *dev, sx126x_rf_mode_t rf_mode);
+#endif
 } sx126x_params_t;
 
 /**
  * @brief   Device descriptor for the driver
  */
-typedef struct {
+struct sx126x {
     netdev_t netdev;                        /**< Netdev parent struct */
     sx126x_params_t *params;                /**< Initialization parameters */
     sx126x_pkt_params_lora_t pkt_params;    /**< Lora packet parameters */
@@ -89,7 +109,7 @@ typedef struct {
     uint32_t channel;                       /**< Current channel frequency (in Hz) */
     uint8_t rx_timeout;                     /**< Rx Timeout in terms of symbols */
     bool radio_sleep;                       /**< Radio sleep status */
-} sx126x_t;
+};
 
 /**
  * @brief   Setup the radio device
diff --git a/drivers/sx126x/include/sx126x_params.h b/drivers/sx126x/include/sx126x_params.h
index c8cd74d8e3..bf40e87919 100644
--- a/drivers/sx126x/include/sx126x_params.h
+++ b/drivers/sx126x/include/sx126x_params.h
@@ -57,6 +57,10 @@ extern "C" {
 #define SX126X_PARAM_REGULATOR              SX126X_REG_MODE_DCDC
 #endif
 
+#ifndef SX126X_PARAM_SET_RF_MODE_CB
+#define SX126X_PARAM_SET_RF_MODE_CB         NULL
+#endif
+
 #ifndef SX126X_PARAM_TYPE
 #    if IS_USED(MODULE_SX1261)
 #        define SX126X_PARAM_TYPE SX126X_TYPE_SX1261
@@ -73,13 +77,21 @@ extern "C" {
 #    endif
 #endif
 
+#if IS_USED(MODULE_SX126X_RF_SWITCH)
+#define SX126X_SET_RF_MODE  .set_rf_mode = SX126X_PARAM_SET_RF_MODE_CB
+#else
+#define SX126X_SET_RF_MODE
+#endif
+
 #define SX126X_PARAMS             { .spi = SX126X_PARAM_SPI,            \
                                     .nss_pin = SX126X_PARAM_SPI_NSS,    \
                                     .reset_pin = SX126X_PARAM_RESET,    \
                                     .busy_pin = SX126X_PARAM_BUSY,      \
                                     .dio1_pin = SX126X_PARAM_DIO1,      \
                                     .type     = SX126X_PARAM_TYPE,      \
-                                    .regulator = SX126X_PARAM_REGULATOR }
+                                    .regulator = SX126X_PARAM_REGULATOR, \
+                                    SX126X_SET_RF_MODE }
+
 /**@}*/
 
 /**
diff --git a/drivers/sx126x/sx126x_netdev.c b/drivers/sx126x/sx126x_netdev.c
index 2287fe7921..cc11b3f388 100644
--- a/drivers/sx126x/sx126x_netdev.c
+++ b/drivers/sx126x/sx126x_netdev.c
@@ -311,6 +311,12 @@ static int _set_state(sx126x_t *dev, netopt_state_t state)
     case NETOPT_STATE_IDLE:
     case NETOPT_STATE_RX:
         DEBUG("[sx126x] netdev: set NETOPT_STATE_RX state\n");
+#if IS_USED(MODULE_SX126X_RF_SWITCH)
+        /* Refer Section 4.2 RF Switch in Application Note (AN5406) */
+        if (dev->params->set_rf_mode) {
+            dev->params->set_rf_mode(dev, SX126X_RF_MODE_RX);
+        }
+#endif
         sx126x_cfg_rx_boosted(dev, true);
         int _timeout = (sx126x_symbol_to_msec(dev, dev->rx_timeout));
         if (_timeout != 0) {
@@ -323,6 +329,11 @@ static int _set_state(sx126x_t *dev, netopt_state_t state)
 
     case NETOPT_STATE_TX:
         DEBUG("[sx126x] netdev: set NETOPT_STATE_TX state\n");
+#if IS_USED(MODULE_SX126X_RF_SWITCH)
+        if (dev->params->set_rf_mode) {
+            dev->params->set_rf_mode(dev, SX126X_RF_MODE_TX_LPA);
+        }
+#endif
         sx126x_set_tx(dev, 0);
         break;