[PATCH lora-next 04/11] net: lora: sx130x: add helper function for writing to the SX130x MCU

[Ben Whitten]

From: Ben Whitten <ben.whitten@xxxxxxxxx>

The transaction to the internal MCU starts with CMD_WAIT to start a
transaction, written to CHRS followed by writing the value, the status of
the command is read back from AGCSTS.

Signed-off-by: Ben Whitten <ben.whitten@xxxxxxxxx>
---
 drivers/net/lora/sx130x.c | 28 ++++++++++++++++++++++++++++
 drivers/net/lora/sx130x.h |  2 ++
 2 files changed, 30 insertions(+)

diff --git a/drivers/net/lora/sx130x.c b/drivers/net/lora/sx130x.c
index 529ca6622878..818a1c9192b3 100644
--- a/drivers/net/lora/sx130x.c
+++ b/drivers/net/lora/sx130x.c
@@ -337,6 +337,34 @@ static int sx130x_load_firmware(struct sx130x_priv *priv, int mcu, const struct
 	return 0;
 }
 
+static int sx130x_agc_transaction(struct sx130x_priv *priv, unsigned int val,
+				  unsigned int *status)
+{
+	int ret;
+
+	ret = regmap_write(priv->regmap, SX1301_CHRS, SX1301_AGC_CMD_WAIT);
+	if (ret) {
+		dev_err(priv->dev, "AGC transaction start failed\n");
+		return ret;
+	}
+	usleep_range(1000, 2000);
+
+	ret = regmap_write(priv->regmap, SX1301_CHRS, val);
+	if (ret) {
+		dev_err(priv->dev, "AGC transaction value failed\n");
+		return ret;
+	}
+	usleep_range(1000, 2000);
+
+	ret = regmap_read(priv->regmap, SX1301_AGCSTS, status);
+	if (ret) {
+		dev_err(priv->dev, "AGC status read failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
 static int sx130x_agc_calibrate(struct sx130x_priv *priv)
 {
 	const struct firmware *fw;
diff --git a/drivers/net/lora/sx130x.h b/drivers/net/lora/sx130x.h
index 6330777f4eac..69bb9cbd1aba 100644
--- a/drivers/net/lora/sx130x.h
+++ b/drivers/net/lora/sx130x.h
@@ -18,6 +18,8 @@
 #define SX1301_MCU_AGC_FW_VERSION 4
 #define SX1301_MCU_AGC_CAL_FW_VERSION 2
 
+#define SX1301_AGC_CMD_WAIT 16
+
 #define SX1301_TX_GAIN_LUT_MAX 16
 
 /* Page independent */
-- 
2.17.1