[PATCH] staging: vt6656: Refactor the vnt_update_pre_ed_threshold function

From: Oscar Carter
Date: Sat Mar 28 2020 - 14:17:43 EST


Create three arrays with the threshold data use in the switch statement
of the vnt_update_pre_ed_threshold function. These three arrays contains
elements of struct vnt_threshold new type.

Create a for loop in the vnt_update_pre_ed_threshold function to do
exactly the same that the if-elseif-else statements in the switch
statement.

Also, remove the if check against the !cr_201 && !cr_206 due to now it
is replace by the NULL check against the threshold pointer. When this
pointer is NULL means that the cr_201 and cr_206 variables have not been
assigned, that is the same that the old comparison against cr_201 and
cr_206 due to these variables were initialized with 0.

The statistics of the old baseband object file are:

section size addr
.text 3415 0
.data 576 0
.bss 0 0
.rodata 120 0
.comment 45 0
.note.GNU-stack 0 0
.note.gnu.property 28 0
Total 4184

The statistics of the new baseband object file are:

section size addr
.text 2209 0
.data 576 0
.bss 0 0
.rodata 344 0
.comment 45 0
.note.GNU-stack 0 0
.note.gnu.property 28 0
Total 3202

With this refactoring it increase a little the readonly data but it
decrease much more the .text section. This refactoring decrease the
footprint and makes the code more clear.

Signed-off-by: Oscar Carter <oscar.carter@xxxxxxx>
---
drivers/staging/vt6656/baseband.c | 335 +++++++++---------------------
1 file changed, 100 insertions(+), 235 deletions(-)

diff --git a/drivers/staging/vt6656/baseband.c b/drivers/staging/vt6656/baseband.c
index a19a563d8bcc..e03f83e1c394 100644
--- a/drivers/staging/vt6656/baseband.c
+++ b/drivers/staging/vt6656/baseband.c
@@ -115,6 +115,86 @@ static const u16 vnt_frame_time[MAX_RATE] = {
10, 20, 55, 110, 24, 36, 48, 72, 96, 144, 192, 216
};

+struct vnt_threshold {
+ u8 bb_pre_ed_rssi;
+ u8 cr_201;
+ u8 cr_206;
+};
+
+static const struct vnt_threshold al2230_vnt_threshold[] = {
+ {0, 0x00, 0x30}, /* Max sensitivity */
+ {68, 0x00, 0x36},
+ {67, 0x00, 0x43},
+ {66, 0x00, 0x51},
+ {65, 0x00, 0x62},
+ {64, 0x00, 0x79},
+ {63, 0x00, 0x93},
+ {62, 0x00, 0xb9},
+ {61, 0x00, 0xe3},
+ {60, 0x01, 0x18},
+ {59, 0x01, 0x54},
+ {58, 0x01, 0xa0},
+ {57, 0x02, 0x20},
+ {56, 0x02, 0xa0},
+ {55, 0x03, 0x00},
+ {53, 0x06, 0x00},
+ {51, 0x09, 0x00},
+ {49, 0x0e, 0x00},
+ {47, 0x15, 0x00},
+ {46, 0x1a, 0x00},
+ {45, 0xff, 0x00}
+};
+
+static const struct vnt_threshold vt3226_vnt_threshold[] = {
+ {0, 0x00, 0x24}, /* Max sensitivity */
+ {68, 0x00, 0x2d},
+ {67, 0x00, 0x36},
+ {66, 0x00, 0x43},
+ {65, 0x00, 0x52},
+ {64, 0x00, 0x68},
+ {63, 0x00, 0x80},
+ {62, 0x00, 0x9c},
+ {61, 0x00, 0xc0},
+ {60, 0x00, 0xea},
+ {59, 0x01, 0x30},
+ {58, 0x01, 0x70},
+ {57, 0x01, 0xb0},
+ {56, 0x02, 0x30},
+ {55, 0x02, 0xc0},
+ {53, 0x04, 0x00},
+ {51, 0x07, 0x00},
+ {49, 0x0a, 0x00},
+ {47, 0x11, 0x00},
+ {45, 0x18, 0x00},
+ {43, 0x26, 0x00},
+ {42, 0x36, 0x00},
+ {41, 0xff, 0x00}
+};
+
+static const struct vnt_threshold vt3342_vnt_threshold[] = {
+ {0, 0x00, 0x38}, /* Max sensitivity */
+ {66, 0x00, 0x43},
+ {65, 0x00, 0x52},
+ {64, 0x00, 0x68},
+ {63, 0x00, 0x80},
+ {62, 0x00, 0x9c},
+ {61, 0x00, 0xc0},
+ {60, 0x00, 0xea},
+ {59, 0x01, 0x30},
+ {58, 0x01, 0x70},
+ {57, 0x01, 0xb0},
+ {56, 0x02, 0x30},
+ {55, 0x02, 0xc0},
+ {53, 0x04, 0x00},
+ {51, 0x07, 0x00},
+ {49, 0x0a, 0x00},
+ {47, 0x11, 0x00},
+ {45, 0x18, 0x00},
+ {43, 0x26, 0x00},
+ {42, 0x36, 0x00},
+ {41, 0xff, 0x00}
+};
+
/*
* Description: Calculate data frame transmitting time
*
@@ -572,254 +652,42 @@ int vnt_exit_deep_sleep(struct vnt_private *priv)

void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
{
- u8 cr_201 = 0x0, cr_206 = 0x0;
+ const struct vnt_threshold *threshold = NULL;
+ u8 length;
+ u8 cr_201, cr_206;
u8 ed_inx = priv->bb_pre_ed_index;

switch (priv->rf_type) {
case RF_AL2230:
case RF_AL2230S:
case RF_AIROHA7230:
- if (scanning) { /* Max sensitivity */
- ed_inx = 0;
- cr_206 = 0x30;
- break;
- }
-
- if (priv->bb_pre_ed_rssi <= 45) {
- ed_inx = 20;
- cr_201 = 0xff;
- } else if (priv->bb_pre_ed_rssi <= 46) {
- ed_inx = 19;
- cr_201 = 0x1a;
- } else if (priv->bb_pre_ed_rssi <= 47) {
- ed_inx = 18;
- cr_201 = 0x15;
- } else if (priv->bb_pre_ed_rssi <= 49) {
- ed_inx = 17;
- cr_201 = 0xe;
- } else if (priv->bb_pre_ed_rssi <= 51) {
- ed_inx = 16;
- cr_201 = 0x9;
- } else if (priv->bb_pre_ed_rssi <= 53) {
- ed_inx = 15;
- cr_201 = 0x6;
- } else if (priv->bb_pre_ed_rssi <= 55) {
- ed_inx = 14;
- cr_201 = 0x3;
- } else if (priv->bb_pre_ed_rssi <= 56) {
- ed_inx = 13;
- cr_201 = 0x2;
- cr_206 = 0xa0;
- } else if (priv->bb_pre_ed_rssi <= 57) {
- ed_inx = 12;
- cr_201 = 0x2;
- cr_206 = 0x20;
- } else if (priv->bb_pre_ed_rssi <= 58) {
- ed_inx = 11;
- cr_201 = 0x1;
- cr_206 = 0xa0;
- } else if (priv->bb_pre_ed_rssi <= 59) {
- ed_inx = 10;
- cr_201 = 0x1;
- cr_206 = 0x54;
- } else if (priv->bb_pre_ed_rssi <= 60) {
- ed_inx = 9;
- cr_201 = 0x1;
- cr_206 = 0x18;
- } else if (priv->bb_pre_ed_rssi <= 61) {
- ed_inx = 8;
- cr_206 = 0xe3;
- } else if (priv->bb_pre_ed_rssi <= 62) {
- ed_inx = 7;
- cr_206 = 0xb9;
- } else if (priv->bb_pre_ed_rssi <= 63) {
- ed_inx = 6;
- cr_206 = 0x93;
- } else if (priv->bb_pre_ed_rssi <= 64) {
- ed_inx = 5;
- cr_206 = 0x79;
- } else if (priv->bb_pre_ed_rssi <= 65) {
- ed_inx = 4;
- cr_206 = 0x62;
- } else if (priv->bb_pre_ed_rssi <= 66) {
- ed_inx = 3;
- cr_206 = 0x51;
- } else if (priv->bb_pre_ed_rssi <= 67) {
- ed_inx = 2;
- cr_206 = 0x43;
- } else if (priv->bb_pre_ed_rssi <= 68) {
- ed_inx = 1;
- cr_206 = 0x36;
- } else {
- ed_inx = 0;
- cr_206 = 0x30;
- }
+ threshold = al2230_vnt_threshold;
+ length = ARRAY_SIZE(al2230_vnt_threshold);
break;

case RF_VT3226:
case RF_VT3226D0:
- if (scanning) { /* Max sensitivity */
- ed_inx = 0;
- cr_206 = 0x24;
- break;
- }
-
- if (priv->bb_pre_ed_rssi <= 41) {
- ed_inx = 22;
- cr_201 = 0xff;
- } else if (priv->bb_pre_ed_rssi <= 42) {
- ed_inx = 21;
- cr_201 = 0x36;
- } else if (priv->bb_pre_ed_rssi <= 43) {
- ed_inx = 20;
- cr_201 = 0x26;
- } else if (priv->bb_pre_ed_rssi <= 45) {
- ed_inx = 19;
- cr_201 = 0x18;
- } else if (priv->bb_pre_ed_rssi <= 47) {
- ed_inx = 18;
- cr_201 = 0x11;
- } else if (priv->bb_pre_ed_rssi <= 49) {
- ed_inx = 17;
- cr_201 = 0xa;
- } else if (priv->bb_pre_ed_rssi <= 51) {
- ed_inx = 16;
- cr_201 = 0x7;
- } else if (priv->bb_pre_ed_rssi <= 53) {
- ed_inx = 15;
- cr_201 = 0x4;
- } else if (priv->bb_pre_ed_rssi <= 55) {
- ed_inx = 14;
- cr_201 = 0x2;
- cr_206 = 0xc0;
- } else if (priv->bb_pre_ed_rssi <= 56) {
- ed_inx = 13;
- cr_201 = 0x2;
- cr_206 = 0x30;
- } else if (priv->bb_pre_ed_rssi <= 57) {
- ed_inx = 12;
- cr_201 = 0x1;
- cr_206 = 0xb0;
- } else if (priv->bb_pre_ed_rssi <= 58) {
- ed_inx = 11;
- cr_201 = 0x1;
- cr_206 = 0x70;
- } else if (priv->bb_pre_ed_rssi <= 59) {
- ed_inx = 10;
- cr_201 = 0x1;
- cr_206 = 0x30;
- } else if (priv->bb_pre_ed_rssi <= 60) {
- ed_inx = 9;
- cr_206 = 0xea;
- } else if (priv->bb_pre_ed_rssi <= 61) {
- ed_inx = 8;
- cr_206 = 0xc0;
- } else if (priv->bb_pre_ed_rssi <= 62) {
- ed_inx = 7;
- cr_206 = 0x9c;
- } else if (priv->bb_pre_ed_rssi <= 63) {
- ed_inx = 6;
- cr_206 = 0x80;
- } else if (priv->bb_pre_ed_rssi <= 64) {
- ed_inx = 5;
- cr_206 = 0x68;
- } else if (priv->bb_pre_ed_rssi <= 65) {
- ed_inx = 4;
- cr_206 = 0x52;
- } else if (priv->bb_pre_ed_rssi <= 66) {
- ed_inx = 3;
- cr_206 = 0x43;
- } else if (priv->bb_pre_ed_rssi <= 67) {
- ed_inx = 2;
- cr_206 = 0x36;
- } else if (priv->bb_pre_ed_rssi <= 68) {
- ed_inx = 1;
- cr_206 = 0x2d;
- } else {
- ed_inx = 0;
- cr_206 = 0x24;
- }
+ threshold = vt3226_vnt_threshold;
+ length = ARRAY_SIZE(vt3226_vnt_threshold);
break;

case RF_VT3342A0:
- if (scanning) { /* need Max sensitivity */
- ed_inx = 0;
- cr_206 = 0x38;
- break;
- }
-
- if (priv->bb_pre_ed_rssi <= 41) {
- ed_inx = 20;
- cr_201 = 0xff;
- } else if (priv->bb_pre_ed_rssi <= 42) {
- ed_inx = 19;
- cr_201 = 0x36;
- } else if (priv->bb_pre_ed_rssi <= 43) {
- ed_inx = 18;
- cr_201 = 0x26;
- } else if (priv->bb_pre_ed_rssi <= 45) {
- ed_inx = 17;
- cr_201 = 0x18;
- } else if (priv->bb_pre_ed_rssi <= 47) {
- ed_inx = 16;
- cr_201 = 0x11;
- } else if (priv->bb_pre_ed_rssi <= 49) {
- ed_inx = 15;
- cr_201 = 0xa;
- } else if (priv->bb_pre_ed_rssi <= 51) {
- ed_inx = 14;
- cr_201 = 0x7;
- } else if (priv->bb_pre_ed_rssi <= 53) {
- ed_inx = 13;
- cr_201 = 0x4;
- } else if (priv->bb_pre_ed_rssi <= 55) {
- ed_inx = 12;
- cr_201 = 0x2;
- cr_206 = 0xc0;
- } else if (priv->bb_pre_ed_rssi <= 56) {
- ed_inx = 11;
- cr_201 = 0x2;
- cr_206 = 0x30;
- } else if (priv->bb_pre_ed_rssi <= 57) {
- ed_inx = 10;
- cr_201 = 0x1;
- cr_206 = 0xb0;
- } else if (priv->bb_pre_ed_rssi <= 58) {
- ed_inx = 9;
- cr_201 = 0x1;
- cr_206 = 0x70;
- } else if (priv->bb_pre_ed_rssi <= 59) {
- ed_inx = 8;
- cr_201 = 0x1;
- cr_206 = 0x30;
- } else if (priv->bb_pre_ed_rssi <= 60) {
- ed_inx = 7;
- cr_206 = 0xea;
- } else if (priv->bb_pre_ed_rssi <= 61) {
- ed_inx = 6;
- cr_206 = 0xc0;
- } else if (priv->bb_pre_ed_rssi <= 62) {
- ed_inx = 5;
- cr_206 = 0x9c;
- } else if (priv->bb_pre_ed_rssi <= 63) {
- ed_inx = 4;
- cr_206 = 0x80;
- } else if (priv->bb_pre_ed_rssi <= 64) {
- ed_inx = 3;
- cr_206 = 0x68;
- } else if (priv->bb_pre_ed_rssi <= 65) {
- ed_inx = 2;
- cr_206 = 0x52;
- } else if (priv->bb_pre_ed_rssi <= 66) {
- ed_inx = 1;
- cr_206 = 0x43;
- } else {
- ed_inx = 0;
- cr_206 = 0x38;
- }
+ threshold = vt3342_vnt_threshold;
+ length = ARRAY_SIZE(vt3342_vnt_threshold);
break;
}

+ if (!threshold)
+ return;
+
+ for (ed_inx = scanning ? 0 : length - 1; ed_inx > 0; ed_inx--) {
+ if (priv->bb_pre_ed_rssi <= threshold[ed_inx].bb_pre_ed_rssi)
+ break;
+ }
+
+ cr_201 = threshold[ed_inx].cr_201;
+ cr_206 = threshold[ed_inx].cr_206;
+
if (ed_inx == priv->bb_pre_ed_index && !scanning)
return;

@@ -828,9 +696,6 @@ void vnt_update_pre_ed_threshold(struct vnt_private *priv, int scanning)
dev_dbg(&priv->usb->dev, "%s bb_pre_ed_rssi %d\n",
__func__, priv->bb_pre_ed_rssi);

- if (!cr_201 && !cr_206)
- return;
-
vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xc9, cr_201);
vnt_control_out_u8(priv, MESSAGE_REQUEST_BBREG, 0xce, cr_206);
}
--
2.20.1