On Fri, Aug 09, 2019 at 01:06:01PM +0200, Hans de Goede wrote:
> Hi,
>
> On 8/9/19 12:01 AM, Yauhen Kharuzhy wrote:
> > Intel Cherry Trail Whiskey Cove extcon driver connect USB data lines to
> > PMIC at driver probing for further charger detection. This causes reset of
> > USB data sessions and removing all devices from bus. If system was
> > booted from Live CD or USB dongle, this makes system unusable.
> >
> > Check if USB ID pin is floating and re-route data lines in this case
> > only, don't touch otherwise.
> >
> > Signed-off-by: Yauhen Kharuzhy <jek...@gmail.com>
> > ---
> > drivers/extcon/extcon-intel-cht-wc.c | 16 ++++++++++++++--
> > 1 file changed, 14 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/extcon/extcon-intel-cht-wc.c
> > b/drivers/extcon/extcon-intel-cht-wc.c
> > index 9d32150e68db..3ae573e93e6e 100644
> > --- a/drivers/extcon/extcon-intel-cht-wc.c
> > +++ b/drivers/extcon/extcon-intel-cht-wc.c
> > @@ -338,6 +338,7 @@ static int cht_wc_extcon_probe(struct platform_device
> > *pdev)
> > struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
> > struct cht_wc_extcon_data *ext;
> > unsigned long mask = ~(CHT_WC_PWRSRC_VBUS | CHT_WC_PWRSRC_USBID_MASK);
> > + int pwrsrc_sts, id;
> > int irq, ret;
> > irq = platform_get_irq(pdev, 0);
> > @@ -387,8 +388,19 @@ static int cht_wc_extcon_probe(struct platform_device
> > *pdev)
> > goto disable_sw_control;
> > }
> > - /* Route D+ and D- to PMIC for initial charger detection */
> > - cht_wc_extcon_set_phymux(ext, MUX_SEL_PMIC);
> > + ret = regmap_read(ext->regmap, CHT_WC_PWRSRC_STS, &pwrsrc_sts);
> > + if (ret) {
> > + dev_err(ext->dev, "Error reading pwrsrc status: %d\n", ret);
> > + goto disable_sw_control;
> > + }
> > +
> > + id = cht_wc_extcon_get_id(ext, pwrsrc_sts);
> > +
> > + /* If no USB host or device connected, route D+ and D- to PMIC for
> > + * initial charger detection
> > + */
> > + if (id == INTEL_USB_ID_FLOAT)
> > + cht_wc_extcon_set_phymux(ext, MUX_SEL_PMIC);
>
> The check here should be != INTEL_USB_ID_GND, when we are connected as
> device we are charging from the host we are connected to and the port
> we are connected to may be a CDP (charging downstream port) instead of
> a SDP (standard downstream port) allowing us to charge at 1.5A instead
> of 0.5A, also != INTEL_USB_ID_GND matches the condition used in
> cht_wc_extcon_pwrsrc_event to determine if we should continue with
> charger detection there.
Actually it should be checked as ((id != INTEL_USB_ID_GND) && (id !=
INTEL_USB_RID_A)), to not interrupt connection if ACA used and our host
is OTG A device (for example, if LiveCD boots from USB flash inserted
into an ACA USB hub).
>
> Like your other patch I will try to give this one a test-run tomorrow.
>
> Regards,
>
> Hans
>
>
> > /* Get initial state */
> > cht_wc_extcon_pwrsrc_event(ext);
> >
--
Yauhen Kharuzhy
