Re: [PATCH v4 20/20] extcon: intel-cht-wc: Report RID_A for ACA adapters

Chanwoo Choi
2021-12-16T02:32:40Z

On 12/6/21 6:33 PM, Hans de Goede wrote:
> Make cht_wc_extcon_get_id() report RID_A for ACA adapters, instead of
> reporting ID_FLOAT.
>
> According to the spec. we should read the USB-ID pin ADC value
> to determine the resistance of the used pull-down resister and
> then return RID_A / RID_B / RID_C based on this. But all "Accessory
> Charger Adapter"s (ACAs) which users can actually buy always use
> a combination of a charging port with one or more USB-A ports, so
> they should always use a resistor indicating RID_A. But the spec
> is hard to read / badly-worded so some of them actually indicate
> they are a RID_B ACA even though they clearly are a RID_A ACA.
>
> To workaround this simply always return INTEL_USB_RID_A, which
> matches all the ACAs which users can actually buy.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> drivers/extcon/extcon-intel-cht-wc.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
[snip]

Acked-by: Chanwoo Choi <cw00.choi@samsung.com>

--
Best Regards,
Chanwoo Choi
Samsung Electronics