Re: [PATCH] usb: dwc2: disable erroneous overcurrent condition

From: Minas Harutyunyan
Date: Wed Oct 18 2017 - 02:08:43 EST


On 10/16/2017 8:40 PM, Marek Vasut wrote:
> On 10/16/2017 03:57 PM, Dinh Nguyen wrote:
>> For the case where an external VBUS is used, we should enable the external
>> VBUS comparator in the driver. This would prevent an unnecessary
>> overcurrent error which would then disable the host port.
>>
>> This patch uses the standard 'disable-over-current' binding to allow of the
>> option of disabling the over-current condition.
>>
>> Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx>
>
> Reviewed-by: Marek Vasut <marex@xxxxxxx>
>
> Similar patch was in U-Boot for two years now and it does the trick indeed.
>
>> ---
>> drivers/usb/dwc2/core.h | 4 ++++
>> drivers/usb/dwc2/hcd.c | 5 +++++
>> drivers/usb/dwc2/params.c | 3 +++
>> 3 files changed, 12 insertions(+)
>>
>> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
>> index 8367d4f9..730d7eb 100644
>> --- a/drivers/usb/dwc2/core.h
>> +++ b/drivers/usb/dwc2/core.h
>> @@ -395,6 +395,9 @@ enum dwc2_ep0_state {
>> * (default when phy_type is UTMI+ or ULPI)
>> * 1 - 6 MHz
>> * (default when phy_type is Full Speed)
>> + * @oc_disable: Flag to disable overcurrent condition.
>> + * 0 - Allow overcurrent condition to get detected
>> + * 1 - Disable overcurrent condtion to get detected
>> * @ts_dline: Enable Term Select Dline pulsing
>> * 0 - No (default)
>> * 1 - Yes
>> @@ -492,6 +495,7 @@ struct dwc2_core_params {
>> bool dma_desc_fs_enable;
>> bool host_support_fs_ls_low_power;
>> bool host_ls_low_power_phy_clk;
>> + bool oc_disable;
>>
>> u8 host_channels;
>> u16 host_rx_fifo_size;
>> diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
>> index c263114..5e20336 100644
>> --- a/drivers/usb/dwc2/hcd.c
>> +++ b/drivers/usb/dwc2/hcd.c
>> @@ -213,6 +213,11 @@ static int dwc2_hs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
>> usbcfg &= ~(GUSBCFG_PHYIF16 | GUSBCFG_DDRSEL);
>> if (hsotg->params.phy_ulpi_ddr)
>> usbcfg |= GUSBCFG_DDRSEL;
>> +
>> + /* Set external VBUS indicator as needed. */
>> + if (hsotg->params.oc_disable)
>> + usbcfg |= (GUSBCFG_ULPI_INT_VBUS_IND |
>> + GUSBCFG_INDICATORPASSTHROUGH);
>> break;
>> case DWC2_PHY_TYPE_PARAM_UTMI:
>> /* UTMI+ interface */
>> diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
>> index a3ffe97..39e02cd 100644
>> --- a/drivers/usb/dwc2/params.c
>> +++ b/drivers/usb/dwc2/params.c
>> @@ -335,6 +335,9 @@ static void dwc2_get_device_properties(struct dwc2_hsotg *hsotg)
>> num);
>> }
>> }
>> +
>> + if (of_find_property(hsotg->dev->of_node, "disable-over-current", NULL))
>> + p->oc_disable = true;
>> }
>>
>> static void dwc2_check_param_otg_cap(struct dwc2_hsotg *hsotg)
>>
>
>
Hi John Youn, I checked with HW team - patch is OK.

Acked-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>