Software Drivers

xgpio.h File Reference

#include "xil_types.h"
#include "xil_assert.h"
#include "xstatus.h"
#include "xgpio_l.h"

Classes

struct  XGpio_Config
struct  XGpio

Defines

#define XGPIO_H

Functions

int XGpio_Initialize (XGpio *InstancePtr, u16 DeviceId)
XGpio_ConfigXGpio_LookupConfig (u16 DeviceId)
int XGpio_CfgInitialize (XGpio *InstancePtr, XGpio_Config *Config, u32 EffectiveAddr)
void XGpio_SetDataDirection (XGpio *InstancePtr, unsigned Channel, u32 DirectionMask)
u32 XGpio_GetDataDirection (XGpio *InstancePtr, unsigned Channel)
u32 XGpio_DiscreteRead (XGpio *InstancePtr, unsigned Channel)
void XGpio_DiscreteWrite (XGpio *InstancePtr, unsigned Channel, u32 Mask)
void XGpio_DiscreteSet (XGpio *InstancePtr, unsigned Channel, u32 Mask)
void XGpio_DiscreteClear (XGpio *InstancePtr, unsigned Channel, u32 Mask)
int XGpio_SelfTest (XGpio *InstancePtr)
void XGpio_InterruptGlobalEnable (XGpio *InstancePtr)
void XGpio_InterruptGlobalDisable (XGpio *InstancePtr)
void XGpio_InterruptEnable (XGpio *InstancePtr, u32 Mask)
void XGpio_InterruptDisable (XGpio *InstancePtr, u32 Mask)
void XGpio_InterruptClear (XGpio *InstancePtr, u32 Mask)
u32 XGpio_InterruptGetEnabled (XGpio *InstancePtr)
u32 XGpio_InterruptGetStatus (XGpio *InstancePtr)

Detailed Description


Define Documentation

#define XGPIO_H

Function Documentation

int XGpio_CfgInitialize ( XGpio InstancePtr,
XGpio_Config Config,
u32  EffectiveAddr 
)

Initialize the XGpio instance provided by the caller based on the given configuration data.

Nothing is done except to initialize the InstancePtr.

Parameters:
InstancePtr is a pointer to an XGpio instance. The memory the pointer references must be pre-allocated by the caller. Further calls to manipulate the driver through the XGpio API must be made with this pointer.
Config is a reference to a structure containing information about a specific GPIO device. This function initializes an InstancePtr object for a specific device specified by the contents of Config. This function can initialize multiple instance objects with the use of multiple calls giving different Config information on each call.
EffectiveAddr is the device base address in the virtual memory address space. The caller is responsible for keeping the address mapping from EffectiveAddr to the device physical base address unchanged once this function is invoked. Unexpected errors may occur if the address mapping changes after this function is called. If address translation is not used, use Config->BaseAddress for this parameters, passing the physical address instead.
Returns:
  • XST_SUCCESS Initialization was successfull.
Note:
None.
void XGpio_DiscreteClear ( XGpio InstancePtr,
unsigned  Channel,
u32  Mask 
)

Set output discrete(s) to logic 0 for the specified GPIO channel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
Mask is the set of bits that will be set to 0 in the discrete data register. All other bits in the data register are unaffected.
Returns:
None.
Note:

The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert.

This API can only be used if the GPIO_IO ports in the IP are used for connecting to the external output ports.

u32 XGpio_DiscreteRead ( XGpio InstancePtr,
unsigned  Channel 
)

Read state of discretes for the specified GPIO channnel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
Returns:
Current copy of the discretes register.
Note:
The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert.
void XGpio_DiscreteSet ( XGpio InstancePtr,
unsigned  Channel,
u32  Mask 
)

Set output discrete(s) to logic 1 for the specified GPIO channel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
Mask is the set of bits that will be set to 1 in the discrete data register. All other bits in the data register are unaffected.
Returns:
None.
Note:

The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert.

This API can only be used if the GPIO_IO ports in the IP are used for connecting to the external output ports.

void XGpio_DiscreteWrite ( XGpio InstancePtr,
unsigned  Channel,
u32  Data 
)

Write to discretes register for the specified GPIO channel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
Data is the value to be written to the discretes register.
Returns:
None.
Note:
The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert. See also XGpio_DiscreteSet() and XGpio_DiscreteClear().
u32 XGpio_GetDataDirection ( XGpio InstancePtr,
unsigned  Channel 
)

Get the input/output direction of all discrete signals for the specified GPIO channel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
Returns:
Bitmask specifying which discretes are input and which are output. Bits set to 0 are output and bits set to 1 are input.
Note:

The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert.

int XGpio_Initialize ( XGpio InstancePtr,
u16  DeviceId 
)

Initialize the XGpio instance provided by the caller based on the given DeviceID.

Nothing is done except to initialize the InstancePtr.

Parameters:
InstancePtr is a pointer to an XGpio instance. The memory the pointer references must be pre-allocated by the caller. Further calls to manipulate the instance/driver through the XGpio API must be made with this pointer.
DeviceId is the unique id of the device controlled by this XGpio instance. Passing in a device id associates the generic XGpio instance to a specific device, as chosen by the caller or application developer.
Returns:
  • XST_SUCCESS if the initialization was successfull.
  • XST_DEVICE_NOT_FOUND if the device configuration data was not found for a device with the supplied device ID.
Note:
None.
void XGpio_InterruptClear ( XGpio InstancePtr,
u32  Mask 
)

Clear pending interrupts with the provided mask. This function should be called after the software has serviced the interrupts that are pending. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Mask is the mask to clear pending interrupts for. Bit positions of 1 are cleared. This mask is formed by OR'ing bits from XGPIO_IR* bits which are contained in xgpio_l.h.
Returns:
None.
Note:
None.
void XGpio_InterruptDisable ( XGpio InstancePtr,
u32  Mask 
)

Disable interrupts. This function allows specific interrupts for each channel to be disabled. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Mask is the mask to disable. Bits set to 1 are disabled. This mask is formed by OR'ing bits from XGPIO_IR* bits which are contained in xgpio_l.h.
Returns:
None.
Note:
None.
void XGpio_InterruptEnable ( XGpio InstancePtr,
u32  Mask 
)

Enable interrupts. The global interrupt must also be enabled by calling XGpio_InterruptGlobalEnable() for interrupts to occur. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Mask is the mask to enable. Bit positions of 1 are enabled. This mask is formed by OR'ing bits from XGPIO_IR* bits which are contained in xgpio_l.h.
Returns:
None.
Note:
None.
u32 XGpio_InterruptGetEnabled ( XGpio InstancePtr  ) 

Returns the interrupt enable mask. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Returns:
A mask of bits made from XGPIO_IR* bits which are contained in xgpio_l.h.
None.
Note:
None.
u32 XGpio_InterruptGetStatus ( XGpio InstancePtr  ) 

Returns the status of interrupt signals. Any bit in the mask set to 1 indicates that the channel associated with the bit has asserted an interrupt condition. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Returns:
A pointer to a mask of bits made from XGPIO_IR* bits which are contained in xgpio_l.h.
Note:

The interrupt status indicates the status of the device irregardless if the interrupts from the devices have been enabled or not through XGpio_InterruptEnable().

void XGpio_InterruptGlobalDisable ( XGpio InstancePtr  ) 

Disable the interrupt output signal. Interrupts enabled through XGpio_InterruptEnable() will no longer be passed through until the global enable bit is set by XGpio_InterruptGlobalEnable(). This function is designed to allow all interrupts (both channels) to be disabled easily for entering a critical section. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Returns:
None.
Note:
None.
void XGpio_InterruptGlobalEnable ( XGpio InstancePtr  ) 

Enable the interrupt output signal. Interrupts enabled through XGpio_InterruptEnable() will not be passed through until the global enable bit is set by this function. This function is designed to allow all interrupts (both channels) to be enabled easily for exiting a critical section. This function will assert if the hardware device has not been built with interrupt capabilities.

Parameters:
InstancePtr is the GPIO instance to operate on.
Returns:
None.
Note:
None.
XGpio_Config* XGpio_LookupConfig ( u16  DeviceId  ) 

Lookup the device configuration based on the unique device ID. The table ConfigTable contains the configuration info for each device in the system.

Parameters:
DeviceId is the device identifier to lookup.
Returns:
  • A pointer of data type XGpio_Config which points to the device configuration if DeviceID is found.
  • NULL if DeviceID is not found.
Note:
None.
int XGpio_SelfTest ( XGpio InstancePtr  ) 

Run a self-test on the driver/device. This function does a minimal test in which the data register is read. It only does a read without any kind of test because the hardware has been parameterized such that it may be only an input such that the state of the inputs won't be known.

All other hardware features of the device are not guaranteed to be in the hardware since they are parameterizable.

Parameters:
InstancePtr is a pointer to the XGpio instance to be worked on. This parameter must have been previously initialized with XGpio_Initialize().
Returns:
XST_SUCCESS always. If the GPIO device was not present in the hardware a bus error could be generated. Other indicators of a bus error, such as registers in bridges or buses, may be necessary to determine if this function caused a bus error.
Note:
None.
void XGpio_SetDataDirection ( XGpio InstancePtr,
unsigned  Channel,
u32  DirectionMask 
)

Set the input/output direction of all discrete signals for the specified GPIO channel.

Parameters:
InstancePtr is a pointer to an XGpio instance to be worked on.
Channel contains the channel of the GPIO (1 or 2) to operate on.
DirectionMask is a bitmask specifying which discretes are input and which are output. Bits set to 0 are output and bits set to 1 are input.
Returns:
None.
Note:
The hardware must be built for dual channels if this function is used with any channel other than 1. If it is not, this function will assert.