qcacmn: Remove identical function bodies to avoid update errors

In change Ia98b97f4cfe47dcd94bfa54f3dd7be13c8696532, the function
'reg_psd_2_eirp' is defined twice:
1)when WLAN_FEATURE_11BE defined
2)when WLAN_FEATURE_11BE is not defined.

However, both the functions are same except that (2) has the following
statement of 3 lines(marked by lines beginning with '>>'):

>>case BW_320_MHZ:
>>ten_log_bw = 25; /* 10* 2.50514 = 25.0514 */
>>break;

and (1) does not have the 3 lines.
Both the functions require identical updates for their the common part.
However, it is very likely to miss updating one function and update
the other function.  Or do different updates for the common part.
Similarly for the non-common part, the function that does not need the
non-common part also may get updated. Therefore, having multiple
identical function bodies for the same function under conditional
compilation is not a good design choice.

Convert the mapping (psd+bw -> eirp) done through 'switch case' into a
linear search through a lookup table. Refactor the code so that there
is only one function body and the non-common part moves to the lookup
table under the conditional compilation.

Change-Id: Ic2c6e7dff5a2fed9d1c6624b042d2be023cafcfc
CRs-Fixed: 3005569

umac/regulatory/core/src/reg_build_chan_list.c

@@ -2643,57 +2643,38 @@ QDF_STATUS reg_get_6g_afc_chan_list(struct wlan_objmgr_pdev *pdev,
 	return QDF_STATUS_SUCCESS;
 }
 
-#ifdef WLAN_FEATURE_11BE
-QDF_STATUS reg_psd_2_eirp(struct wlan_objmgr_pdev *pdev,
-			  int16_t psd,
-			  uint16_t ch_bw,
-			  int16_t *eirp)
-{
-	struct wlan_regulatory_pdev_priv_obj *pdev_priv_obj;
-	int16_t ten_log_bw;
-
-	pdev_priv_obj = reg_get_pdev_obj(pdev);
-
-	if (!IS_VALID_PDEV_REG_OBJ(pdev_priv_obj)) {
-		reg_err("reg pdev private obj is NULL");
-		return QDF_STATUS_E_FAILURE;
-	}
+/**
+ * struct bw_10log10_pair - The bandwidth and 10*log10(bandwidth) pair.
+ * ten_l_len = trunc(10*log10(bw)).  'trunc' is truncation function.
+ * @bw: The input bandwidth
+ * @ten_l_ten: Integer value of 10 times the Logarithm (to the base-10) of the
+ * input bandwidth(@bw).
+ */
+struct bw_10log10_pair {
+	uint16_t bw;
+	int16_t ten_l_ten;
+};
 
-	/**
-	 * EIRP = PSD + 10 * log10(CH_BW)
-	 */
-	switch (ch_bw) {
-	case BW_20_MHZ:
-		ten_log_bw = 13; /*  10* 1.30102 = 13.0102 */
-		break;
-	case BW_40_MHZ:
-		ten_log_bw = 16; /* 10* 1.60205 = 16.0205 */
-		break;
-	case BW_80_MHZ:
-		ten_log_bw = 19; /* 10* 1.90308 = 19.0308 */
-		break;
-	case BW_160_MHZ:
-		ten_log_bw = 22; /* 10* 2.20411 = 22.0411 */
-		break;
-	case BW_320_MHZ:
-		ten_log_bw = 25; /* 10* 2.50514 = 25.0514 */
-		break;
-	default:
-		reg_err("Invalid input bandwidth %hd", ch_bw);
-		return QDF_STATUS_E_FAILURE;
-	}
-	*eirp = psd + ten_log_bw;
+/* The array of bandwidth to trunc(10log10(bandwidth)) mapping */
+static const struct bw_10log10_pair bw_to_10log10_map[] = {
+	{ 20, 13}, /* 10* 1.30102 = 13.0102 */
+	{ 40, 16}, /* 10* 1.60205 = 16.0205 */
+	{ 80, 19}, /* 10* 1.90308 = 19.0308 */
+	{160, 22}, /* 10* 2.20411 = 22.0411 */
+#ifdef WLAN_FEATURE_11BE
+	{320, 25}, /* 10* 2.50514 = 25.0514 */
+#endif
+};
 
-	return QDF_STATUS_SUCCESS;
-}
-#else
 QDF_STATUS reg_psd_2_eirp(struct wlan_objmgr_pdev *pdev,
 			  int16_t psd,
 			  uint16_t ch_bw,
 			  int16_t *eirp)
 {
 	struct wlan_regulatory_pdev_priv_obj *pdev_priv_obj;
-	int16_t ten_log_bw;
+	int16_t ten_log10_bw;
+	uint8_t i;
+	uint8_t num_bws;
 
 	pdev_priv_obj = reg_get_pdev_obj(pdev);
 
@@ -2702,29 +2683,16 @@ QDF_STATUS reg_psd_2_eirp(struct wlan_objmgr_pdev *pdev,
 		return QDF_STATUS_E_FAILURE;
 	}
 
-	/**
-	 * EIRP = PSD + 10 * log10(CH_BW)
-	 */
-	switch (ch_bw) {
-	case BW_20_MHZ:
-		ten_log_bw = 13; /*  10* 1.30102 = 13.0102 */
-		break;
-	case BW_40_MHZ:
-		ten_log_bw = 16; /* 10* 1.60205 = 16.0205 */
-		break;
-	case BW_80_MHZ:
-		ten_log_bw = 19; /* 10* 1.90308 = 19.0308 */
-		break;
-	case BW_160_MHZ:
-		ten_log_bw = 22; /* 10* 2.20411 = 22.0411 */
-		break;
-	default:
-		reg_err("Invalid input bandwidth %hd", ch_bw);
-		return QDF_STATUS_E_FAILURE;
+	/* EIRP = PSD + (10 * log10(CH_BW)) */
+	num_bws = QDF_ARRAY_SIZE(bw_to_10log10_map);
+	for (i = 0; i < num_bws; i++) {
+		if (ch_bw == bw_to_10log10_map[i].bw) {
+			ten_log10_bw = bw_to_10log10_map[i].ten_l_ten;
+			*eirp = psd + ten_log10_bw;
+			return QDF_STATUS_SUCCESS;
+		}
 	}
-	*eirp = psd + ten_log_bw;
-
-	return QDF_STATUS_SUCCESS;
+	reg_err("Invalid input bandwidth %hd", ch_bw);
+	return QDF_STATUS_E_FAILURE;
 }
 #endif
-#endif