DMA Interface. More...

Data Structures
struct	dma_block_config
	DMA block configuration structure. More...

struct	dma_config
	DMA configuration structure. More...

struct	dma_status

struct	dma_context

Macros
#define	DMA_MAGIC 0x47494749

Typedefs
typedef void(*	dma_callback_t) (const struct device dev, void user_data, uint32_t channel, int status)
	Callback function for DMA transfer completion. More...

Enumerations
enum	dma_channel_direction { MEMORY_TO_MEMORY = 0x0 , MEMORY_TO_PERIPHERAL , PERIPHERAL_TO_MEMORY , PERIPHERAL_TO_PERIPHERAL }

enum	dma_addr_adj { DMA_ADDR_ADJ_INCREMENT , DMA_ADDR_ADJ_DECREMENT , DMA_ADDR_ADJ_NO_CHANGE }

enum	dma_channel_filter { DMA_CHANNEL_NORMAL , DMA_CHANNEL_PERIODIC }

Functions
static int	dma_config (const struct device dev, uint32_t channel, struct dma_config config)
	Configure individual channel for DMA transfer. More...

static int	dma_reload (const struct device *dev, uint32_t channel, uint32_t src, uint32_t dst, size_t size)
	Reload buffer(s) for a DMA channel. More...

int	dma_start (const struct device *dev, uint32_t channel)
	Enables DMA channel and starts the transfer, the channel must be configured beforehand. More...

int	dma_stop (const struct device *dev, uint32_t channel)
	Stops the DMA transfer and disables the channel. More...

int	dma_request_channel (const struct device dev, void filter_param)
	request DMA channel. More...

void	dma_release_channel (const struct device *dev, uint32_t channel)
	release DMA channel. More...

int	dma_chan_filter (const struct device dev, int channel, void filter_param)
	DMA channel filter. More...

static int	dma_get_status (const struct device dev, uint32_t channel, struct dma_status stat)
	get current runtime status of DMA transfer More...

static uint32_t	dma_width_index (uint32_t size)
	Look-up generic width index to be used in registers. More...

static uint32_t	dma_burst_index (uint32_t burst)
	Look-up generic burst index to be used in registers. More...

Detailed Description

DMA Interface.

Macro Definition Documentation

◆ DMA_MAGIC

#define DMA_MAGIC 0x47494749

#include <include/drivers/dma.h>

Typedef Documentation

◆ dma_callback_t

dma_callback_t

#include <include/drivers/dma.h>

Callback function for DMA transfer completion.

If enabled, callback function will be invoked at transfer completion or when error happens.

Parameters

dev	Pointer to the DMA device calling the callback.
user_data	A pointer to some user data or NULL
channel	The channel number
status	0 on success, a negative errno otherwise

Enumeration Type Documentation

◆ dma_addr_adj

enum dma_addr_adj

#include <include/drivers/dma.h>

Valid values for source_addr_adj and dest_addr_adj

Enumerator
DMA_ADDR_ADJ_INCREMENT
DMA_ADDR_ADJ_DECREMENT
DMA_ADDR_ADJ_NO_CHANGE

◆ dma_channel_direction

enum dma_channel_direction

#include <include/drivers/dma.h>

Enumerator
MEMORY_TO_MEMORY
MEMORY_TO_PERIPHERAL
PERIPHERAL_TO_MEMORY
PERIPHERAL_TO_PERIPHERAL

◆ dma_channel_filter

enum dma_channel_filter

#include <include/drivers/dma.h>

Enumerator
DMA_CHANNEL_NORMAL
DMA_CHANNEL_PERIODIC

Function Documentation

◆ dma_burst_index()

static uint32_t dma_burst_index ( uint32_t burst )

inlinestatic

#include <include/drivers/dma.h>

Look-up generic burst index to be used in registers.

WARNING: This look-up works for most controllers, but may not work for yours. Ensure your controller expects the most common register bit values before using this convenience function. If your controller does not support these values, you will have to write your own look-up inside the controller driver.

Parameters

burst number of bytes to be sent in a single burst

Return values

common DMA index to be placed into registers.

◆ dma_chan_filter()

int dma_chan_filter	(	const struct device *	dev,
		int	channel,
		void *	filter_param
	)

#include <include/drivers/dma.h>

DMA channel filter.

filter channel by attribute

Parameters

dev	Pointer to the device structure for the driver instance.
channel	channel number
filter_param	filter attribute

Return values

Negative errno code if not support

◆ dma_config()

static int dma_config	(	const struct device *	dev,
		uint32_t	channel,
		struct dma_config *	config
	)

inlinestatic

#include <include/drivers/dma.h>

Configure individual channel for DMA transfer.

Parameters

dev	Pointer to the device structure for the driver instance.
channel	Numeric identification of the channel to configure
config	Data structure containing the intended configuration for the selected channel

Return values

0	if successful.
Negative	errno code if failure.

◆ dma_get_status()

static int dma_get_status	(	const struct device *	dev,
		uint32_t	channel,
		struct dma_status *	stat
	)

inlinestatic

#include <include/drivers/dma.h>

get current runtime status of DMA transfer

Implementations must check the validity of the channel ID passed in and return -EINVAL if it is invalid or -ENOSYS if not supported.

Parameters

dev	Pointer to the device structure for the driver instance.
channel	Numeric identification of the channel where the transfer was being processed
stat	a non-NULL dma_status object for storing DMA status

Return values

non-negative	if successful.
Negative	errno code if failure.

◆ dma_release_channel()

void dma_release_channel	(	const struct device *	dev,
		uint32_t	channel
	)

#include <include/drivers/dma.h>

release DMA channel.

release DMA channel resources

Parameters

dev	Pointer to the device structure for the driver instance.
channel	channel number

◆ dma_reload()

static int dma_reload	(	const struct device *	dev,
		uint32_t	channel,
		uint32_t	src,
		uint32_t	dst,
		size_t	size
	)

inlinestatic

#include <include/drivers/dma.h>

Reload buffer(s) for a DMA channel.

Parameters

dev	Pointer to the device structure for the driver instance.
channel	Numeric identification of the channel to configure selected channel
src	source address for the DMA transfer
dst	destination address for the DMA transfer
size	size of DMA transfer

Return values

0	if successful.
Negative	errno code if failure.

◆ dma_request_channel()

int dma_request_channel	(	const struct device *	dev,
		void *	filter_param
	)

#include <include/drivers/dma.h>

request DMA channel.

request DMA channel resources return -EINVAL if there is no valid channel available.

Parameters

dev	Pointer to the device structure for the driver instance.
filter_param	filter function parameter

Return values

dma	channel if successful.
Negative	errno code if failure.

◆ dma_start()

int dma_start	(	const struct device *	dev,
		uint32_t	channel
	)

#include <include/drivers/dma.h>

Enables DMA channel and starts the transfer, the channel must be configured beforehand.

Implementations must check the validity of the channel ID passed in and return -EINVAL if it is invalid.

Parameters

dev	Pointer to the device structure for the driver instance.
channel	Numeric identification of the channel where the transfer will be processed

Return values

0	if successful.
Negative	errno code if failure.

◆ dma_stop()

int dma_stop	(	const struct device *	dev,
		uint32_t	channel
	)

#include <include/drivers/dma.h>

Stops the DMA transfer and disables the channel.

Implementations must check the validity of the channel ID passed in and return -EINVAL if it is invalid.

Parameters

dev	Pointer to the device structure for the driver instance.
channel	Numeric identification of the channel where the transfer was being processed

Return values

0	if successful.
Negative	errno code if failure.

◆ dma_width_index()

static uint32_t dma_width_index ( uint32_t size )

inlinestatic

#include <include/drivers/dma.h>

Look-up generic width index to be used in registers.

WARNING: This look-up works for most controllers, but may not work for yours. Ensure your controller expects the most common register bit values before using this convenience function. If your controller does not support these values, you will have to write your own look-up inside the controller driver.

Parameters

size	width of bus (in bytes)

Return values

common DMA index to be placed into registers.

Data Structures

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ DMA_MAGIC

Typedef Documentation

◆ dma_callback_t

Enumeration Type Documentation

◆ dma_addr_adj

◆ dma_channel_direction

◆ dma_channel_filter

Function Documentation

◆ dma_burst_index()

◆ dma_chan_filter()

◆ dma_config()

◆ dma_get_status()

◆ dma_release_channel()

◆ dma_reload()

◆ dma_request_channel()

◆ dma_start()

◆ dma_stop()

◆ dma_width_index()