staging: rtl8723bs: refactor rtw_ch2freq()

Convert the array ch_freq_map to a simple integer array and use
the indices as channel numbers. This simplifies the code and avoids
looping through the array to get the frequency. To avoid out of
bounds array access return a default value for invalid channel values,
like the original code did.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20220331214146.15161-3-straube.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rtl8723bs/core/rtw_rf.c b/drivers/staging/rtl8723bs/core/rtw_rf.c
index 7e4bf42fd1acdb26a21fe40e7b0d3aff3dc37646..4f120c894998d25ee908897ce5c5aca6144654cc 100644 (file)
--- a/drivers/staging/rtl8723bs/core/rtw_rf.c
+++ b/drivers/staging/rtl8723bs/core/rtw_rf.c
@@ -8,31 +8,27 @@
 #include <drv_types.h>
 #include <linux/kernel.h>
 
-
-struct ch_freq {
-       u32 channel;
-       u32 frequency;
-};
-
-static struct ch_freq ch_freq_map[] = {
-       {1, 2412}, {2, 2417}, {3, 2422}, {4, 2427}, {5, 2432},
-       {6, 2437}, {7, 2442}, {8, 2447}, {9, 2452}, {10, 2457},
-       {11, 2462}, {12, 2467}, {13, 2472}, {14, 2484},
+static const u32 ch_freq_map[] = {
+       2412,
+       2417,
+       2422,
+       2427,
+       2432,
+       2437,
+       2442,
+       2447,
+       2452,
+       2457,
+       2462,
+       2467,
+       2472,
+       2484
 };
 
 u32 rtw_ch2freq(u32 channel)
 {
-       u8 i;
-       u32 freq = 0;
-
-       for (i = 0; i < ARRAY_SIZE(ch_freq_map); i++) {
-               if (channel == ch_freq_map[i].channel) {
-                       freq = ch_freq_map[i].frequency;
-                               break;
-               }
-       }
-       if (i == ARRAY_SIZE(ch_freq_map))
-               freq = 2412;
+       if (channel == 0 || channel > ARRAY_SIZE(ch_freq_map))
+               return 2412;
 
-       return freq;
+       return ch_freq_map[channel - 1];
 }