Re: [PATCH 2/2] i2c-mxs: fixed PIO NACK error instead of timeout

[Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>]

On Monday, September 08, 2014 at 08:06:12 PM, Janusz Użycki wrote:
> Subject: [PATCH 2/2] i2c-mxs: fixed PIO NACK error instead of timeout
>   (1000ms)
> 
> i2cdetect scanned i2c bus very slow if address was not occupied by any
> device.

Shouldn't this check be used only after the 'SELECT' command ?

> Signed-off-by: Janusz Uzycki <j.uzycki-9tnw74Q4ehaHKKo6LODCOg@public.gmane.org>
> ---
>   linux-3.14.17/drivers/i2c/busses/i2c-mxs.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/linux-3.14.17/drivers/i2c/busses/i2c-mxs.c
> b/linux-3.14.17/drivers/i2c/busses/i2c-mxs.c
> index 87ee72d..b498708 100644
> --- a/linux-3.14.17/drivers/i2c/busses/i2c-mxs.c
> +++ b/linux-3.14.17/drivers/i2c/busses/i2c-mxs.c
> @@ -307,6 +307,9 @@ static int mxs_i2c_pio_wait_xfer_end(struct
> mxs_i2c_dev *i2c)
>          unsigned long timeout = jiffies + msecs_to_jiffies(1000);
> 
>          while (readl(i2c->regs + MXS_I2C_CTRL0) & MXS_I2C_CTRL0_RUN) {
> +               /*int ret = mxs_i2c_pio_check_error_state(i2c);*/
> +               if (readl(i2c->regs + MXS_I2C_CTRL1) &
> MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ)
> +                       return -ENXIO;
>                  if (time_after(jiffies, timeout))
>                          return -ETIMEDOUT;
>                  cond_resched();
> --
> 1.7.11.3

Best regards,
Marek Vasut