linux-media.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jean Delvare <khali@linux-fr.org>
To: LMML <linux-media@vger.kernel.org>
Cc: Steven Toth <stoth@kernellabs.com>
Subject: [PATCH 5/5] cx22702: Simplify cx22702_set_tps()
Date: Fri, 10 Sep 2010 15:36:37 +0200	[thread overview]
Message-ID: <20100910153637.183d366a@hyperion.delvare> (raw)
In-Reply-To: <20100910151943.103f7423@hyperion.delvare>

Code in function cx22702_set_tps() can be slightly simplified.
Apparently gcc was smart enough to optimize it anyway, but it can't
hurt to make the code more readable.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Steven Toth <stoth@kernellabs.com>
---
 drivers/media/dvb/frontends/cx22702.c |   58 ++++++++++++++-------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

--- linux-2.6.32-rc5.orig/drivers/media/dvb/frontends/cx22702.c	2009-10-17 14:50:42.000000000 +0200
+++ linux-2.6.32-rc5/drivers/media/dvb/frontends/cx22702.c	2009-10-17 16:12:39.000000000 +0200
@@ -316,33 +316,31 @@ static int cx22702_set_tps(struct dvb_fr
 	}
 
 	/* manually programmed values */
-	val = 0;
-	switch (p->u.ofdm.constellation) {
+	switch (p->u.ofdm.constellation) {		/* mask 0x18 */
 	case QPSK:
-		val = (val & 0xe7);
+		val = 0x00;
 		break;
 	case QAM_16:
-		val = (val & 0xe7) | 0x08;
+		val = 0x08;
 		break;
 	case QAM_64:
-		val = (val & 0xe7) | 0x10;
+		val = 0x10;
 		break;
 	default:
 		dprintk("%s: invalid constellation\n", __func__);
 		return -EINVAL;
 	}
-	switch (p->u.ofdm.hierarchy_information) {
+	switch (p->u.ofdm.hierarchy_information) {	/* mask 0x07 */
 	case HIERARCHY_NONE:
-		val = (val & 0xf8);
 		break;
 	case HIERARCHY_1:
-		val = (val & 0xf8) | 1;
+		val |= 0x01;
 		break;
 	case HIERARCHY_2:
-		val = (val & 0xf8) | 2;
+		val |= 0x02;
 		break;
 	case HIERARCHY_4:
-		val = (val & 0xf8) | 3;
+		val |= 0x03;
 		break;
 	default:
 		dprintk("%s: invalid hierarchy\n", __func__);
@@ -350,44 +348,42 @@ static int cx22702_set_tps(struct dvb_fr
 	}
 	cx22702_writereg(state, 0x06, val);
 
-	val = 0;
-	switch (p->u.ofdm.code_rate_HP) {
+	switch (p->u.ofdm.code_rate_HP) {		/* mask 0x38 */
 	case FEC_NONE:
 	case FEC_1_2:
-		val = (val & 0xc7);
+		val = 0x00;
 		break;
 	case FEC_2_3:
-		val = (val & 0xc7) | 0x08;
+		val = 0x08;
 		break;
 	case FEC_3_4:
-		val = (val & 0xc7) | 0x10;
+		val = 0x10;
 		break;
 	case FEC_5_6:
-		val = (val & 0xc7) | 0x18;
+		val = 0x18;
 		break;
 	case FEC_7_8:
-		val = (val & 0xc7) | 0x20;
+		val = 0x20;
 		break;
 	default:
 		dprintk("%s: invalid code_rate_HP\n", __func__);
 		return -EINVAL;
 	}
-	switch (p->u.ofdm.code_rate_LP) {
+	switch (p->u.ofdm.code_rate_LP) {		/* mask 0x07 */
 	case FEC_NONE:
 	case FEC_1_2:
-		val = (val & 0xf8);
 		break;
 	case FEC_2_3:
-		val = (val & 0xf8) | 1;
+		val |= 0x01;
 		break;
 	case FEC_3_4:
-		val = (val & 0xf8) | 2;
+		val |= 0x02;
 		break;
 	case FEC_5_6:
-		val = (val & 0xf8) | 3;
+		val |= 0x03;
 		break;
 	case FEC_7_8:
-		val = (val & 0xf8) | 4;
+		val |= 0x04;
 		break;
 	default:
 		dprintk("%s: invalid code_rate_LP\n", __func__);
@@ -395,30 +391,28 @@ static int cx22702_set_tps(struct dvb_fr
 	}
 	cx22702_writereg(state, 0x07, val);
 
-	val = 0;
-	switch (p->u.ofdm.guard_interval) {
+	switch (p->u.ofdm.guard_interval) {		/* mask 0x0c */
 	case GUARD_INTERVAL_1_32:
-		val = (val & 0xf3);
+		val = 0x00;
 		break;
 	case GUARD_INTERVAL_1_16:
-		val = (val & 0xf3) | 0x04;
+		val = 0x04;
 		break;
 	case GUARD_INTERVAL_1_8:
-		val = (val & 0xf3) | 0x08;
+		val = 0x08;
 		break;
 	case GUARD_INTERVAL_1_4:
-		val = (val & 0xf3) | 0x0c;
+		val = 0x0c;
 		break;
 	default:
 		dprintk("%s: invalid guard_interval\n", __func__);
 		return -EINVAL;
 	}
-	switch (p->u.ofdm.transmission_mode) {
+	switch (p->u.ofdm.transmission_mode) {		/* mask 0x03 */
 	case TRANSMISSION_MODE_2K:
-		val = (val & 0xfc);
 		break;
 	case TRANSMISSION_MODE_8K:
-		val = (val & 0xfc) | 1;
+		val |= 0x1;
 		break;
 	default:
 		dprintk("%s: invalid transmission_mode\n", __func__);

-- 
Jean Delvare

      parent reply	other threads:[~2010-09-10 13:36 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-09-10 13:19 [PATCH 0/5] Clean-ups to the cx22702 frontend driver Jean Delvare
2010-09-10 13:27 ` [PATCH 1/5] cx22702: Clean up register access functions Jean Delvare
2010-09-10 15:13   ` Mauro Carvalho Chehab
2010-09-10 17:03     ` [PATCH 1/5 v2] " Jean Delvare
2010-09-10 13:32 ` [PATCH 2/5] cx22702: Drop useless initializations to 0 Jean Delvare
2010-09-10 13:33 ` [PATCH 3/5] cx22702: Avoid duplicating code in branches Jean Delvare
2010-09-10 13:35 ` [PATCH 4/5] cx22702: Some things never change Jean Delvare
2010-09-10 13:36 ` Jean Delvare [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20100910153637.183d366a@hyperion.delvare \
    --to=khali@linux-fr.org \
    --cc=linux-media@vger.kernel.org \
    --cc=stoth@kernellabs.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).