Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Oscar Carter <oscar.carter@gmx.com>
To:     Forest Bond <forest@alittletooquiet.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Oscar Carter <oscar.carter@gmx.com>,
        Malcolm Priestley <tvboxspy@gmail.com>,
        Quentin Deslandes <quentin.deslandes@itdev.co.uk>,
        Amir Mahdi Ghorbanian <indigoomega021@gmail.com>,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: [PATCH] staging: vt6656: Refactor the vnt_update_pre_ed_threshold function
Date:   Sat, 28 Mar 2020 19:17:06 +0100
Message-Id: <20200328181706.14276-1-oscar.carter@gmx.com>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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@gmx.com>
=2D--
 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/ba=
seband.c
index a19a563d8bcc..e03f83e1c394 100644
=2D-- a/drivers/staging/vt6656/baseband.c
+++ b/drivers/staging/vt6656/baseband.c
@@ -115,6 +115,86 @@ static const u16 vnt_frame_time[MAX_RATE] =3D {
 	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[] =3D {
+	{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[] =3D {
+	{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[] =3D {
+	{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 =3D 0x0, cr_206 =3D 0x0;
+	const struct vnt_threshold *threshold =3D NULL;
+	u8 length;
+	u8 cr_201, cr_206;
 	u8 ed_inx =3D priv->bb_pre_ed_index;

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

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

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

+	if (!threshold)
+		return;
+
+	for (ed_inx =3D scanning ? 0 : length - 1; ed_inx > 0; ed_inx--) {
+		if (priv->bb_pre_ed_rssi <=3D threshold[ed_inx].bb_pre_ed_rssi)
+			break;
+	}
+
+	cr_201 =3D threshold[ed_inx].cr_201;
+	cr_206 =3D threshold[ed_inx].cr_206;
+
 	if (ed_inx =3D=3D priv->bb_pre_ed_index && !scanning)
 		return;

@@ -828,9 +696,6 @@ void vnt_update_pre_ed_threshold(struct vnt_private *p=
riv, 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);
 }
=2D-
2.20.1