Hi Anand, On Wed, Jan 23, 2019 at 4:12 PM Anand Moon <linux.amoon@xxxxxxxxx> wrote: > > Meson8b support two USB phy controller, one with otg port and > other usb host controller. USB OTG controller ie. otg port can > be used to power on board or host port for usb device. > Changes enable usb otg host controller when dr_mode is set to otg. can you please add a sentence explaining *why* this allows enabling USB OTG? > Currenly otg port can be used to power on the board. typo, should be "Currently" > Cc: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > Cc: Jerome Brunet <jbrunet@xxxxxxxxxxxx> > Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx> > Cc: Kevin Hilman <khilman@xxxxxxxxxxxx> > Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx> > --- > New patch in this series. > --TOTO enable OTG port to work as host. > --Currently we can power on the board from this OTG port. > > /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M > |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M > |__ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=usb-storage, 480M > |__ Port 3: Dev 3, If 0, Class=Video, Driver=uvcvideo, 480M > |__ Port 3: Dev 3, If 1, Class=Video, Driver=uvcvideo, 480M > |__ Port 3: Dev 3, If 2, Class=Audio, Driver=snd-usb-audio, 480M > |__ Port 3: Dev 3, If 3, Class=Audio, Driver=snd-usb-audio, 480M > /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc2/1p, 480M > --- > drivers/phy/amlogic/phy-meson8b-usb2.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/phy/amlogic/phy-meson8b-usb2.c b/drivers/phy/amlogic/phy-meson8b-usb2.c > index 9c01b7e19b06..1333c77e9172 100644 > --- a/drivers/phy/amlogic/phy-meson8b-usb2.c > +++ b/drivers/phy/amlogic/phy-meson8b-usb2.c > @@ -109,6 +109,7 @@ > > #define RESET_COMPLETE_TIME 500 > #define ACA_ENABLE_COMPLETE_TIME 50 > +#define DCD_ENABLE_COMPLETE_TIME 10 > > struct phy_meson8b_usb2_priv { > void __iomem *regs; > @@ -188,6 +189,20 @@ static int phy_meson8b_usb2_power_on(struct phy *phy) > > udelay(ACA_ENABLE_COMPLETE_TIME); > > + if (phy_meson8b_usb2_read(priv, REG_ADP_BC) & > + REG_ADP_BC_ACA_PIN_FLOAT) { > + dev_warn(&phy->dev, "USB ID detect failed!\n"); > + clk_disable_unprepare(priv->clk_usb); > + clk_disable_unprepare(priv->clk_usb_general); > + return -EINVAL; > + } > + } else if (priv->dr_mode == USB_DR_MODE_OTG) { > + phy_meson8b_usb2_mask_bits(priv, REG_ADP_BC, > + REG_ADP_BC_DCD_ENABLE, > + REG_ADP_BC_DCD_ENABLE); where did you take this from? $ grep -iR DCD arm-src-kernel-2015-01-15-321cfb5a46/drivers/amlogic/usb/dwc_otg/310/ -> I only find code which clears REG_ADP_BC_DCD_ENABLE (your patch sets it): adp_bc.b.dcd_enable = 0; > + udelay(DCD_ENABLE_COMPLETE_TIME); from Amlogic's code: DWC_MDELAY(T_DCD_TIMEOUT); while you are also using a delay of "10" the unit is different (your patch: us, Amlogic: ms) Regards Martin