SLVUCR8B September   2023  – August 2026 TPS25751

 

  1.   1
  2.   Read This First
    1.     Notational Conventions
    2.     Glossary
    3.     Related Documents
    4.     Support Resources
    5.     Trademarks
  3. 1Introduction
    1. 1.1 Introduction
      1. 1.1.1 Purpose and Scope
    2. 1.2 PD Controller Host Interface Description
      1. 1.2.1 Overview
      2. 1.2.2 Register and Field Notation
    3. 1.3 Unique Address Interface
      1. 1.3.1 Unique Address Interface Protocol
  4. 2PD Controller Policy Modes
    1. 2.1 Overview
    2. 2.2 Source Policy Mode
    3. 2.3 Sink Policy Mode
  5. 3Unique Address Interface Register Detailed Descriptions
    1. 3.1 Register Overview
    2. 3.2 TPS25751 Registers
  6. 44CC Task Detailed Descriptions
    1. 4.1 Overview
    2. 4.2 CPU Control Tasks
      1. 4.2.1 'Gaid' - Return to Normal Operation
      2. 4.2.2 'GAID' - Cold Reset Request
    3. 4.3 PD Message Tasks
      1. 4.3.1 'SWSk' - PD PR_Swap to Sink
      2. 4.3.2 'SWSr' - PD PR_Swap to Source
      3. 4.3.3 'SWDF' - PD DR_Swap to DFP
      4. 4.3.4 'SWUF' - PD DR_Swap to UFP
      5. 4.3.5 'GSkC' - PD Get Sink Capabilities
      6. 4.3.6 'GSrC' - PD Get Source Capabilities
      7. 4.3.7 'GPPI' - PD Get Port Partner Information
      8. 4.3.8 'SSrC' - PD Send Source Capabilities
      9. 4.3.9 'MBRd' - Message Buffer Read
    4. 4.4 Power Switch Tasks
      1. 4.4.1 'SRDY' - System Ready to Sink Power
      2. 4.4.2 'SRYR' - SRDY reset
    5. 4.5 Patch Bundle Update Tasks
      1. 4.5.1 'PBMs' - Start Patch Burst Mode Download Sequence
      2. 4.5.2 'PBMc' - Patch Burst Mode Download Complete
      3. 4.5.3 'PBMe' - End Patch Burst Mode Download Sequence
      4. 4.5.4 'GO2P' - Go to Patch Mode
      5. 4.5.5 'FLrd' - Flash Memory Read
      6. 4.5.6 'FLad' - Flash Memory Write Start Address
      7. 4.5.7 'FLwd' - Flash Memory Write
      8. 4.5.8 'FLvy' - Flash Memory Verify
    6. 4.6 System Tasks
      1. 4.6.1 ANeg: Auto Negotiate Sink Update
      2. 4.6.2 'DBfg' - Clear Dead Battery Flag
      3. 4.6.3 'I2Cr' - I2C Read Transaction
      4. 4.6.4 'I2Cw' - I2C Write Transaction
      5. 4.6.5 'GPsh' - set GPIO high
      6. 4.6.6 'GPsl' - set GPIO low
  7. 5User Reference
    1. 5.1 PD Controller Application Customization
    2. 5.2 Loading a Patch Bundle
    3. 5.3 AUTO_NEGOTIATE_SINK Register
      1. 5.3.1 AUTO_NEGOTIATE_SINK Usage Example 1
      2. 5.3.2 AUTO_NEGOTIATE_SINK Usage Example 2
      3. 5.3.3 AUTO_NEGOTIATE_SINK Usage Example 3
      4. 5.3.4 AUTO_NEGOTIATE_SINK Usage Example 4
    4. 5.4 GPIO Events
  8. 6Revision History

4.3.2 'SWSr' - PD PR_Swap to Source

Table 4-5 'SWSr' - PD PR_Swap to Source
DescriptionThe 'SWSr' Task instructs PD Controller to attempt to become a Source through PR_Swap at the first opportunity while maintaining policy engine compliance.
INPUT DATAXNone
OUTPUT DATAXByte 1: Standard Task Return Code
Task CompletionThe 'SWSr' Task completes either when the PR_Swap is finished or it is otherwise determined to not be possible or fails. The Task can continue to run because of Wait messages being sent by the Sink. The 'SWSr' Task shall be considered rejected if:
  • The Sink previously indicated through Sink or Source Capabilities that it does not support Dual-Role Power.
  • The PR_Swap is Rejected by the port-partner.
The 'SWSr' Task shall be considered timed-out if:
  • The PR_Swap is Accepted but failed to complete per the PD spec.
The 'SWSr' Task shall be considered successful if:
  • PD Controller is already in the Source power role.
  • The PR_Swap is Accepted and completes normally.
Side EffectsAfter the SWSr task completes successfully, the PD controller transitions to the Source power role, affecting related registers. If the PR Swap fails after the Accept, the PD specification mandates a subsequent soft and/or hard reset.
Additional InformationNone