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

Sascha Hauer
2009-10-01T07:26:43Z

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-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>
> 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

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