drivers/ng_at86rf2xx: Refactor set_freq implementation for 212B

Uses BPSK-40 for all frequencies.

drivers/ng_at86rf2xx/ng_at86rf2xx_getset.c

@@ -138,38 +138,38 @@ ng_at86rf2xx_freq_t ng_at86rf2xx_get_freq(ng_at86rf2xx_t *dev)
 
 void ng_at86rf2xx_set_freq(ng_at86rf2xx_t *dev, ng_at86rf2xx_freq_t freq)
 {
-    uint8_t tmp1 = 0, tmp2 = 0;
-    tmp1 = ng_at86rf2xx_reg_read(dev, NG_AT86RF2XX_REG__TRX_CTRL_2);
-    tmp1 &= ~(NG_AT86RF2XX_TRX_CTRL_2_MASK__FREQ_MODE);
-    tmp2 = ng_at86rf2xx_reg_read(dev, NG_AT86RF2XX_REG__RF_CTRL_0);
+    uint8_t trx_ctrl2 = 0, rf_ctrl0 = 0;
+    trx_ctrl2 = ng_at86rf2xx_reg_read(dev, NG_AT86RF2XX_REG__TRX_CTRL_2);
+    trx_ctrl2 &= ~(NG_AT86RF2XX_TRX_CTRL_2_MASK__FREQ_MODE);
+    rf_ctrl0 = ng_at86rf2xx_reg_read(dev, NG_AT86RF2XX_REG__RF_CTRL_0);
     /* Erase previous conf for GC_TX_OFFS */
-    tmp2 &= ~NG_AT86RF2XX_RF_CTRL_0_MASK__GC_TX_OFFS;
-
-    if (freq == NG_AT86RF2XX_FREQ_915MHZ) {
-        dev->freq = NG_AT86RF2XX_FREQ_915MHZ;
-        /* settings used by Linux 4.0rc at86rf212b driver - BPSK-40*/
-        tmp1 |= NG_AT86RF2XX_TRX_CTRL_2_MASK__SUB_MODE
-              | NG_AT86RF2XX_TRX_CTRL_2_MASK__OQPSK_SCRAM_EN;
-        tmp2 |= NG_AT86RF2XX_RF_CTRL_0_GC_TX_OFFS__2DB;
-
-        if (dev->chan == 0) {
-            ng_at86rf2xx_set_chan(dev,NG_AT86RF2XX_DEFAULT_CHANNEL);
-        } else {
-            ng_at86rf2xx_set_chan(dev,dev->chan);
-        }
-    } else if (freq == NG_AT86RF2XX_FREQ_868MHZ) {
-        dev->freq = NG_AT86RF2XX_FREQ_868MHZ;
-        /* OQPSK-SIN-RC-100 IEEE802.15.4 for 868,3MHz */
-        tmp1 |= NG_AT86RF2XX_TRX_CTRL_2_MASK__BPSK_OQPSK;
-        tmp2 |= NG_AT86RF2XX_RF_CTRL_0_GC_TX_OFFS__1DB;
-
-        /* Channel = 0 for 868MHz means 868.3MHz, only one available */
-        ng_at86rf2xx_set_chan(dev,0x00);
-    } else {
-        return;
+    rf_ctrl0 &= ~NG_AT86RF2XX_RF_CTRL_0_MASK__GC_TX_OFFS;
+
+    trx_ctrl2 |= NG_AT86RF2XX_TRX_CTRL_2_MASK__SUB_MODE;
+    rf_ctrl0 |= NG_AT86RF2XX_RF_CTRL_0_GC_TX_OFFS__2DB;
+
+    switch(freq) {
+        case NG_AT86RF2XX_FREQ_915MHZ:
+            if (dev->chan == 0) {
+                ng_at86rf2xx_set_chan(dev,NG_AT86RF2XX_DEFAULT_CHANNEL);
+            } else {
+                ng_at86rf2xx_set_chan(dev,dev->chan);
+            }
+            break;
+
+        case NG_AT86RF2XX_FREQ_868MHZ:
+            /* Channel = 0 for 868MHz means 868.3MHz, only one available */
+            ng_at86rf2xx_set_chan(dev,0x00);
+            break;
+
+        default:
+            DEBUG("ng_at86rf2xx: Trying to set unknown frequency 0x%lx\n",
+                (unsigned long) freq);
+            return;
     }
-    ng_at86rf2xx_reg_write(dev, NG_AT86RF2XX_REG__TRX_CTRL_2, tmp1);
-    ng_at86rf2xx_reg_write(dev, NG_AT86RF2XX_REG__RF_CTRL_0, tmp2);
+    dev->freq = freq;
+    ng_at86rf2xx_reg_write(dev, NG_AT86RF2XX_REG__TRX_CTRL_2, trx_ctrl2);
+    ng_at86rf2xx_reg_write(dev, NG_AT86RF2XX_REG__RF_CTRL_0, rf_ctrl0);
 }
 #endif