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References: <20220628024913.1755292-1-tzungbi@kernel.org> <20220628024913.1755292-8-tzungbi@kernel.org>
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From:   Guenter Roeck <groeck@google.com>
Date:   Wed, 13 Jul 2022 11:18:32 -0700
Message-ID: <CABXOdTft0Nu_hJQuXwepBXE3tWZf7jaidGE5mamq_=1Zi4hevg@mail.gmail.com>
Subject: Re: [RESEND PATCH 07/11] platform/chrome: cros_ec_proto: return
 -EAGAIN when retries timed out
To:     Tzung-Bi Shih <tzungbi@kernel.org>
Cc:     Benson Leung <bleung@chromium.org>,
        Guenter Roeck <groeck@chromium.org>,
        "open list:CHROME HARDWARE PLATFORM SUPPORT" 
        <chrome-platform@lists.linux.dev>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Mon, Jun 27, 2022 at 7:49 PM Tzung-Bi Shih <tzungbi@kernel.org> wrote:
>
> While EC_COMMS_STATUS_PROCESSING flag is still on after it tries
> EC_COMMAND_RETRIES times for sending EC_CMD_GET_COMMS_STATUS,
> cros_ec_wait_until_complete() doesn't return an error code.
>
> Return -EAGAIN in the case instead.

Does this make sense, or should it be -ETIMEDOUT ? What does the EC do
if it is still busy (stuck ?) with executing a command and it gets
another one ?

>
> Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
> ---
>  drivers/platform/chrome/cros_ec_proto.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
> index 466ecb063bd6..49772a4c5353 100644
> --- a/drivers/platform/chrome/cros_ec_proto.c
> +++ b/drivers/platform/chrome/cros_ec_proto.c
> @@ -167,6 +167,9 @@ static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *
>                         break;
>         }
>
> +       if (i >= EC_COMMAND_RETRIES)
> +               ret = -EAGAIN;
> +
>         kfree(msg);
>         return ret;
>  }
> --
> 2.37.0.rc0.161.g10f37bed90-goog
>