From: Gregory Herrero <gregory.herrero@xxxxxxxxx> When booting with id pin grounded, dwc2 default to host mode. Thus, force device mode prior initializing gadget part. Else fifo init will fail since fifo values are not correct in host mode. Signed-off-by: Gregory Herrero <gregory.herrero@xxxxxxxxx> --- drivers/usb/dwc2/gadget.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c index 8afac3c..8b6f5c5 100644 --- a/drivers/usb/dwc2/gadget.c +++ b/drivers/usb/dwc2/gadget.c @@ -3693,6 +3693,19 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq) /* usb phy enable */ s3c_hsotg_phy_enable(hsotg); + /* + * Force Device mode before initialization. + * This allows correctly configuring fifo for device mode. + */ + __bic32(hsotg->regs + GUSBCFG, GUSBCFG_FORCEHOSTMODE); + __orr32(hsotg->regs + GUSBCFG, GUSBCFG_FORCEDEVMODE); + + /* + * According to Synopsys databook, this sleep is needed for the force + * device mode to take effect. + */ + msleep(25); + s3c_hsotg_corereset(hsotg); ret = s3c_hsotg_hw_cfg(hsotg); if (ret) { @@ -3702,6 +3715,9 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq) s3c_hsotg_init(hsotg); + /* Switch back to default configuration */ + __bic32(hsotg->regs + GUSBCFG, GUSBCFG_FORCEDEVMODE); + hsotg->ctrl_buff = devm_kzalloc(hsotg->dev, DWC2_CTRL_BUFF_SIZE, GFP_KERNEL); if (!hsotg->ctrl_buff) { -- 1.9.1 ---------------------------------------------------------------------- Intel Sweden AB Registered Office: Knarrarnasgatan 15, 164 40 Kista, Stockholm, Sweden Registration Number: 556189-6027 This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html