Media subsystem kernel internal API

Copyright © 2009-2016 : LinuxTV Developers

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Table of Contents

• 1. Video4Linux devices
  • 1.1. Introduction
  • 1.2. Structure of a V4L driver
  • 1.3. Structure of the V4L2 framework
  • 1.4. Video device’ s internal representation
    • 1.4.1. ioctls and locking
    • 1.4.2. Video device registration
    • 1.4.3. video device debugging
    • 1.4.4. Video device cleanup
    • 1.4.5. helper functions
    • 1.4.6. video_device functions and data structures
  • 1.5. V4L2 device instance
    • 1.5.1. v4l2_device functions and data structures
  • 1.6. V4L2 File handlers
    • 1.6.1. V4L2 fh functions and data structures
  • 1.7. V4L2 sub-devices
  • 1.8. V4L2 sub-device userspace API
  • 1.9. I2C sub-device drivers
  • 1.10. V4L2 sub-device functions and data structures
  • 1.11. V4L2 events
    • 1.11.1. Event subscription
    • 1.11.2. Unsubscribing an event
    • 1.11.3. Check if there’s a pending event
    • 1.11.4. How events work
      • 1.11.4.1. V4L2 event functions and data structures
  • 1.12. V4L2 Controls
    • 1.12.1. Introduction
    • 1.12.2. Objects in the framework
    • 1.12.3. Basic usage for V4L2 and sub-device drivers
    • 1.12.4. Inheriting Sub-device Controls
    • 1.12.5. Accessing Control Values
    • 1.12.6. Menu Controls
    • 1.12.7. Custom Controls
    • 1.12.8. Active and Grabbed Controls
    • 1.12.9. Control Clusters
    • 1.12.10. Handling autogain/gain-type Controls with Auto Clusters
    • 1.12.11. VIDIOC_LOG_STATUS Support
    • 1.12.12. Different Handlers for Different Video Nodes
    • 1.12.13. Finding Controls
    • 1.12.14. Preventing Controls inheritance
    • 1.12.15. V4L2_CTRL_TYPE_CTRL_CLASS Controls
    • 1.12.16. Adding Notify Callbacks
    • 1.12.17. v4l2_ctrl functions and data structures
  • 1.13. Videobuf Framework
    • 1.13.1. Introduction
    • 1.13.2. Buffer types
    • 1.13.3. Data structures, callbacks, and initialization
    • 1.13.4. File operations
    • 1.13.5. ioctl() operations
    • 1.13.6. Buffer allocation
    • 1.13.7. Filling the buffers
  • 1.14. V4L2 videobuf2 functions and data structures
  • 1.15. V4L2 clocks
  • 1.16. V4L2 DV Timings functions
  • 1.17. V4L2 flash functions and data structures
  • 1.18. V4L2 Media Controller functions and data structures
  • 1.19. V4L2 Media Bus functions and data structures
  • 1.20. V4L2 Memory to Memory functions and data structures
  • 1.21. V4L2 async kAPI
  • 1.22. V4L2 fwnode kAPI
  • 1.23. V4L2 rect helper functions
  • 1.24. Tuner functions and data structures
  • 1.25. V4L2 common functions and data structures
  • 1.26. Hauppauge TV EEPROM functions and data structures
• 2. Digital TV (DVB) devices
  • 2.1. Digital TV Common functions
    • 2.1.1. Math functions
    • 2.1.2. DVB devices
    • 2.1.3. Digital TV Ring buffer
    • 2.1.4. Digital TV VB2 handler
  • 2.2. Digital TV Frontend kABI
    • 2.2.1. Digital TV Frontend
      • 2.2.1.1. Demodulator driver
      • 2.2.1.2. Attaching frontend driver to the bridge driver
    • 2.2.2. Digital TV Frontend statistics
      • 2.2.2.1. Introduction
      • 2.2.2.2. Groups of statistics
      • 2.2.2.3. Statistics collection
        • 2.2.2.3.1. if the driver have a bit that indicates when a collected data is ready
        • 2.2.2.3.2. If the driver doesn’t provide a statistics available check bit
    • 2.2.3. Digital TV Frontend functions and types
  • 2.3. Digital TV Demux kABI
    • 2.3.1. Digital TV Demux
    • 2.3.2. Demux Callback API
    • 2.3.3. Digital TV Demux device registration functions and data structures
    • 2.3.4. High-level Digital TV demux interface
    • 2.3.5. Driver-internal low-level hardware specific driver demux interface
  • 2.4. Digital TV Conditional Access kABI
  • 2.5. Digital TV Network kABI
• 3. Remote Controller devices
  • 3.1. Remote Controller core
    • 3.1.1. Remote controller data structures and functions
• 4. Media Controller devices
  • 4.1. Media Controller
    • 4.1.1. Abstract media device model
    • 4.1.2. Media device
    • 4.1.3. Entities
    • 4.1.4. Interfaces
    • 4.1.5. Pads
    • 4.1.6. Links
    • 4.1.7. Graph traversal
    • 4.1.8. Use count and power handling
    • 4.1.9. Links setup
    • 4.1.10. Pipelines and media streams
    • 4.1.11. Link validation
    • 4.1.12. Media Controller Device Allocator API
    • 4.1.13. API Definitions
• 5. CEC Kernel Support
  • 5.1. The CEC Protocol
  • 5.2. CEC Adapter Interface
  • 5.3. Implementing the Low-Level CEC Adapter
  • 5.4. Implementing the interrupt handler
  • 5.5. Optional: Implementing Error Injection Support
  • 5.6. Implementing the High-Level CEC Adapter
  • 5.7. CEC framework functions
  • 5.8. CEC Pin framework
  • 5.9. CEC Notifier framework
• 6. MIPI CSI-2
  • 6.1. Transmitter drivers
    • 6.1.1. Stopping the transmitter
  • 6.2. Receiver drivers
  • 6.3. Formats