[PATCH 07/12] viafb: reduce I2C timeout and delay

From: Florian Tobias Schandinat
Date: Sun Sep 19 2010 - 03:22:59 EST


viafb: reduce I2C timeout and delay

This patch reduces the value for I2C timeout and udelay.
The udelay was reduced to 10 (old: 40) which is still very high as for
standard-mode I2C even 5 should work. This gives a speedup of factor 4
when talking to I2C devices.
The timeout was reduced to 2 (old: 20) which is taken from the radeon
driver so it should work as well. This gives a speedup of factor 10 when
detecting that there is no I2C device we want to talk to.
This causes a huge improvement of device initialization time.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@xxxxxx>
Cc: Joseph Chan <JosephChan@xxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
---
drivers/video/via/via_i2c.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/via/via_i2c.c b/drivers/video/via/via_i2c.c
index 021112e..3844b55 100644
--- a/drivers/video/via/via_i2c.c
+++ b/drivers/video/via/via_i2c.c
@@ -202,8 +202,8 @@ static int create_i2c_bus(struct i2c_adapter *adapter,
algo->setscl = via_i2c_setscl;
algo->getsda = via_i2c_getsda;
algo->getscl = via_i2c_getscl;
- algo->udelay = 40;
- algo->timeout = 20;
+ algo->udelay = 10;
+ algo->timeout = 2;
algo->data = adap_cfg;

sprintf(adapter->name, "viafb i2c io_port idx 0x%02x",
--
1.6.3.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/