Re: [PATCH v4] extcon: int3496: process id-pin first so that we start with the right status

Chanwoo Choi
2018-02-19T09:55:28Z

Hi,

On 2018년 02월 14일 04:25, Hans de Goede wrote:
> Some other drivers may be waiting for our extcon to show-up, exiting their
> probe methods with -EPROBE_DEFER until we show up.
>
> These drivers will typically get the cable state directly after getting
> the extcon, this commit changes the int3496 code to wait for the initial
> processing of the id-pin to complete before exiting probe() with 0, which
> will cause devices waiting on the defered probe to get reprobed.
>
> This fixes a race where the initial work might still be running while other
> drivers were already calling extcon_get_state().
>
> Fixes: 2f556bdb9f2e ("extcon: int3496: Add Intel INT3496 ACPI ... driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Changes in v2:
> -Add Fixes tag
>
> Changes in v3:
> -Fix oops on probe by scheduling the work too early
>
> Changes in v4:
> -Ugh sorry about this, but we cannot call extcon_set_state() before
> extcon_dev_register() at all because before registration the cable array
> is not yet allocated. Instead wait for the initial processing of the
> id-pin to complete before exiting probe().
> ---
> drivers/extcon/extcon-intel-int3496.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/extcon/extcon-intel-int3496.c b/drivers/extcon/extcon-intel-int3496.c
> index c8691b5a9cb0..191e99f06a9a 100644
> --- a/drivers/extcon/extcon-intel-int3496.c
> +++ b/drivers/extcon/extcon-intel-int3496.c
> @@ -153,8 +153,9 @@ static int int3496_probe(struct platform_device *pdev)
> return ret;
> }
>
> - /* queue initial processing of id-pin */
> + /* process id-pin so that we start with the right status */
> queue_delayed_work(system_wq, &data->work, 0);
> + flush_delayed_work(&data->work);
>
> platform_set_drvdata(pdev, data);
>
>

Applied it instead of v3.

--
Best Regards,
Chanwoo Choi
Samsung Electronics