[PATCH 2/4] i2c: imx: only imx1 needs disable delay

[Sascha Hauer]

On Thu, Oct 01, 2009 at 09:13:31AM +0800, Richard Zhao wrote:
> check cpu_is_mx1() when set disable_delay.
> 
> Signed-off-by: Richard Zhao <linuxzsc at gmail.com>
> 
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 156cc95..c1e541c 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -254,14 +254,16 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
>  	/* Write divider value to register */
>  	writeb(i2c_clk_div[i][1], i2c_imx->base + IMX_I2C_IFDR);
>  
> -	/*
> -	 * There dummy delay is calculated.
> -	 * It should be about one I2C clock period long.
> -	 * This delay is used in I2C bus disable function
> -	 * to fix chip hardware bug.
> -	 */
> -	i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
> -		+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
> +	if (cpu_is_mx1()) {
> +		/*
> +		 * There dummy delay is calculated.
> +		 * It should be about one I2C clock period long.
> +		 * This delay is used in I2C bus disable function
> +		 * to fix chip hardware bug.
> +		 */
> +		i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
> +			+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
> +	}

I think you should put the udelay(i2c_imx->disable_delay) in
cpu_is_mx1() rather than the calculation.

Sascha


-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |