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DMA ​

DMA Driver.

Functions for interacting with peripheral devices via DMA

Functions Overview ​

Name
cw_driver_return_tdma_acquire_channel(int hDev, dma_cb cb, void * p)
Acquires a DMA channel.
cw_driver_return_tdma_release_channel(int hDev, unsigned int channel)
Releases a DMA channel.
cw_driver_return_tdma_acquire_syncbit(int hDev)
Acquires the synchronization bit for a DMA device.
cw_driver_return_tdma_release_syncbit(int hDev, uint16_t bit)
Releases a synchronization bit in a DMA channel.

Function Details ​

function dma_acquire_channel ​

cpp
cw_driver_return_t dma_acquire_channel(
    int hDev,
    dma_cb cb,
    void * p
)

Acquires a DMA channel.

Parameters:

  • hDev The handle of the device.
  • cb Callback function to be called when DMA transfer is complete.
  • p User-defined data to be passed to the callback function.

Return: cw_driver_return_t Returns CW_DRIVER_SUCCESS if successful, otherwise returns an error code.

This function acquires a DMA channel for the specified device.

function dma_release_channel ​

cpp
cw_driver_return_t dma_release_channel(
    int hDev,
    unsigned int channel
)

Releases a DMA channel.

Parameters:

  • hDev The handle to the device.
  • channel The channel number to release.

Return: Returns 0 on success, or a negative value on failure.

This function releases a DMA channel associated with a device.

function dma_acquire_syncbit ​

cpp
cw_driver_return_t dma_acquire_syncbit(
    int hDev
)

Acquires the synchronization bit for a DMA device.

Parameters:

  • hDev The handle of the DMA device.

Return: None

This function acquires the synchronization bit for the given DMA device.

function dma_release_syncbit ​

cpp
cw_driver_return_t dma_release_syncbit(
    int hDev,
    uint16_t bit
)

Releases a synchronization bit in a DMA channel.

Parameters:

  • hDev The handle of the device.
  • bit The synchronization bit to be released.

Return: The result of the operation. Returns 0 on success, or a negative error code otherwise.

This function releases a synchronization bit in a DMA channel specified by the device handle. The synchronization bit that needs to be released is specified by the bit parameter.