Commit 84bf2c86 authored by Aaro Koskinen's avatar Aaro Koskinen Committed by Ben Dooks

i2c: OMAP3: Better noise suppression for fast/standard modes

Use longer noise filter period for fast and standard mode. Based on an
earlier patch by Eero Nurkkala.
Signed-off-by: default avatarAaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarBen Dooks <ben-linux@fluff.org>
parent baf46b4e
...@@ -333,8 +333,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) ...@@ -333,8 +333,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
if (cpu_is_omap2430() || cpu_is_omap34xx()) { if (cpu_is_omap2430() || cpu_is_omap34xx()) {
/* HSI2C controller internal clk rate should be 19.2 Mhz */ /*
* HSI2C controller internal clk rate should be 19.2 Mhz for
* HS and for all modes on 2430. On 34xx we can use lower rate
* to get longer filter period for better noise suppression.
* The filter is iclk (fclk for HS) period.
*/
if (dev->speed > 400 || cpu_is_omap_2430())
internal_clk = 19200; internal_clk = 19200;
else if (dev->speed > 100)
internal_clk = 9600;
else
internal_clk = 4000;
fclk_rate = clk_get_rate(dev->fclk) / 1000; fclk_rate = clk_get_rate(dev->fclk) / 1000;
/* Compute prescaler divisor */ /* Compute prescaler divisor */
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment