[PATCH] at91sam9g45: fix i2c bus speed

[nicolas.ferre@atmel.com (Nicolas Ferre)]

Le 22/09/2010 11:31, Peter Korsgaard :
> Use a correct udelay value to get bus speed around 100KHz. The udelay
> value was most likely copied from the older devices, but the 9g45
> is signicantly faster (400MHz, DDR, ..), so a udelay of 2 gives a
> bus speed of around 190KHz, which is too fast for some devices.
> A udelay value of 5 gives a bus speed of around 90KHz here.
> 
> Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

> ---
>  arch/arm/mach-at91/at91sam9g45_devices.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c
> index 5e71ccd..1276bab 100644
> --- a/arch/arm/mach-at91/at91sam9g45_devices.c
> +++ b/arch/arm/mach-at91/at91sam9g45_devices.c
> @@ -426,7 +426,7 @@ static struct i2c_gpio_platform_data pdata_i2c0 = {
>  	.sda_is_open_drain	= 1,
>  	.scl_pin		= AT91_PIN_PA21,
>  	.scl_is_open_drain	= 1,
> -	.udelay			= 2,		/* ~100 kHz */
> +	.udelay			= 5,		/* ~100 kHz */
>  };
>  
>  static struct platform_device at91sam9g45_twi0_device = {
> @@ -440,7 +440,7 @@ static struct i2c_gpio_platform_data pdata_i2c1 = {
>  	.sda_is_open_drain	= 1,
>  	.scl_pin		= AT91_PIN_PB11,
>  	.scl_is_open_drain	= 1,
> -	.udelay			= 2,		/* ~100 kHz */
> +	.udelay			= 5,		/* ~100 kHz */
>  };
>  
>  static struct platform_device at91sam9g45_twi1_device = {


-- 
Nicolas Ferre