3 Replies Latest reply on Jan 16, 2020 1:25 AM by YashwantK_46

    Query about Cypress FX3 Errata Low Power U1 Fast-Exit Issue with USB3.0 host controller.

    PrM_1403381

      Hi,

       

      I am using Cypress Fx3 DVK (CYUSB3KIT-003), In cypress errata I found about above mentioned subject.

       

      So in firmware, In CyFxUSBEventCB function in CY_U3P_USB_EVENT_SETCONF function I am making LPM disable CyU3PUsbLPMDisable(), and I am not making enable anywhere. I sthis method of making LPM disable is correct or any other way I need to handle.

      Here is the snippet of my CyFxUSBEventCB function:

      void

      CyFxUSBEventCB (

          CyU3PUsbEventType_t evtype, /* Event type */

          uint16_t            evdata  /* Event data */

          )

      {

          switch (evtype)

          {

          case CY_U3P_USB_EVENT_CONNECT:

              case CY_U3P_USB_EVENT_SETCONF:

                  /* Stop the application before restarting. */

                  if (glIsApplnActive)

                  {

                      CyFxIntrSrcSinkApplnStop ();

                  }

                  CyU3PConnectState(CyTrue, CyTrue);

       

                  CyU3PUsbLPMDisable();

       

                  CyFxIntrSrcSinkApplnStart ();

       

                  CyU3PUsbStart();

                  break;

       

       

              case CY_U3P_USB_EVENT_RESET:

              case CY_U3P_USB_EVENT_DISCONNECT:

                  /* Stop the loop back function. */

                  if (glIsApplnActive)

                  {

                      CyFxIntrSrcSinkApplnStop ();

                  }

                  break;

       

              default:

                  break;

          }

      }

       

      â– Workaround

      This problem can be worked around in the FW by disabling LPM (Link Power Management) during data transfer.

      Since it is mentioned that during data transfer means where I need to disable LPM ?

       

      Best Regards

      Prasanna