[PATCH 7/8] bt856: Spare memory

From: Jean Delvare
Date: Mon Mar 13 2006 - 15:32:52 EST


The bt856 driver has a register cache much larger than needed. We
really only write to 3 registers, so a 32-byte cache is a bit too
much. We can be just as efficient with a 6-byte cache. We could even
do with a 3-byte cache, but at the cost of additional arithmetics
arguably not worth the spared 3 bytes.

Also, 4 of the 6 other members of the bt856 data structure were not
used anywhere, so we can as well drop them for an additional 16 bytes
of memory spared.

Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx>
---
drivers/media/video/bt856.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

--- linux-2.6.16-rc5.orig/drivers/media/video/bt856.c 2006-03-01 21:09:59.000000000 +0100
+++ linux-2.6.16-rc5/drivers/media/video/bt856.c 2006-03-01 21:10:19.000000000 +0100
@@ -70,17 +70,14 @@

/* ----------------------------------------------------------------------- */

-#define REG_OFFSET 0xCE
+#define REG_OFFSET 0xDA
+#define BT856_NR_REG 6

struct bt856 {
- unsigned char reg[32];
+ unsigned char reg[BT856_NR_REG];

int norm;
int enable;
- int bright;
- int contrast;
- int hue;
- int sat;
};

#define I2C_BT856 0x88
@@ -119,8 +116,8 @@
struct bt856 *encoder = i2c_get_clientdata(client);

printk(KERN_INFO "%s: register dump:", I2C_NAME(client));
- for (i = 0xd6; i <= 0xde; i += 2)
- printk(" %02x", encoder->reg[i - REG_OFFSET]);
+ for (i = 0; i < BT856_NR_REG; i += 2)
+ printk(" %02x", encoder->reg[i]);
printk("\n");
}


--
Jean Delvare
-
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