Keyscan

Data Structures
struct	KeyscanRegistration
	Keyscan event notification registration structure. Internal. More...
struct	KeyscanState
	Keyscan driver state. More...

Modules
	KeyscanQueue

Typedefs
typedef struct KeyscanRegistration	KeyscanRegistration
	Keyscan event notification registration structure. Internal.

Enumerations
enum	{ EVENT_NONE = 0xfd }
	Defines the standard keyscan driver. More...
enum	{   HW_CTRL_SCAN_CTRL_MASK = 0x00001, HW_CTRL_GHOST_DETECT_MASK = 0x00004, HW_CTRL_INTERRUPT_CTRL_MASK = 0x00008, HW_CTRL_RESET_MASK = 0x00010,   HW_CTRL_RC_EXT_MASK = 0x000C0, HW_CTRL_ROW_MASK = 0x00700, HW_CTRL_COL_MASK = 0x0F800, HW_CTRL_COL_DRIVE_CTRL_MASK = 0x10000,   HW_CTRL_ROW_DRIVE_CTRL_MASK = 0x20000, HW_CTRL_SCAN_ENABLE = 0x00001, HW_CTRL_GHOST_ENABLE = 0x00004, HW_CTRL_KS_INTERRUPT_ENABLE = 0x00008,   HW_CTRL_RESET_ENABLE = 0x00010, HW_CTRL_CLK_ALWAYS_ON = 0x40000, HW_CTRL_RC_DEFAULT = 0x000C0, HW_CTRL_ROW_SHIFT = 8,   HW_CTRL_COL_SHIFT = 11, HW_CTRL_COL_ACTIVE_DRIVE = 0x10000, HW_CTRL_ROW_ACTIVE_DRIVE = 0x20000, HW_CTRL_SCAN_DISABLE = 0x00000,   HW_CTRL_GHOST_DISABLE = 0x00000, HW_CTRL_INTERRUPT_DISABLE = 0x00000, HW_CTRL_RESET_DISABLE = 0x00000, HW_CTRL_CLK_AUTO_CTRL = 0x00000,   HW_CTRL_COLUMN_PASSIVE_DRIVE = 0x00000, HW_CTRL_ROW_PASSIVE_DRIVE = 0x00000 }
	Internal HW control and status bits.
enum	{ HW_MIA_STATUS_KEYSCAN_INT_SET_MASK = 0x00040 }
	Keyscan interrupt mask. Internal.
enum	{ HW_LHL_CTRL_CLR_KEYS = 0x0002, HW_LHL_STATUS_GHOST = 0x0008, HW_LHL_STATUS_KEY_FIFO_OVERFLOW = 0x0004, HW_LHL_STATUS_KEYCODE = 0x0002 }
	Keyscan HW status bits. Internal.
enum	{   HW_KEYCODE_MASK = 0x000000ff, HW_SCAN_CYCLE_MASK = 0x40000000, HW_KEY_UP_DOWN_MASK = (int)0x80000000, HW_KEYCODE_SHIFT_COUNT = 0,   HW_SCAN_CYCLE_SHIFT_COUNT = 30, HW_KEY_UP_DOWN_SHIFT_COUNT = 31, HW_KEYCODE_GHOST = 0xf5, HW_KEYCODE_INIT = 0xff,   HW_KEY_UP = (int)0x80000000, HW_KEY_DOWN = 0x00000000 }
	Keyscan configuration and status bits.
enum	{ CH_SEL_KEYSCAN_ROW_INPUT_50_57 = 0x0000, CH_SEL_KEYSCAN_ROW_INPUT_16_23 = 0x0001 }

Functions
void	keyscan_init (void)
	Keyscan driver initialization function. More...
void	keyscan_reset (void)
	Reset the keyscan HW. Any existing events will be thrown away.
BOOL32	keyscan_eventsPending (void)
	Check if there are any pending key events. More...
BOOL32	keyscan_getNextEvent (KeyEvent *event)
	Get next key event. More...
void	keyscan_turnOff (void)
	Disables keyscanning and and any associated wakeup.
void	keyscan_turnOn (void)
	Enabled keyscanning and and any associated wakeup functionality. More...
void	keyscan_registerForEventNotification (void(*userfn)(void *), void *userdata)
	Register for notification of changes. More...
void	keyscan_enableEventDetection (void)
	Configures the interrupt source from Keyscan HW and enables event detection. More...
void	keyscan_flushHwEvents (void)
	Clears the keys in the HW queue.
void	keyscan_miaFreezeCallBack (void)
	MIA clock freeze notification. More...
void	keyscan_miaUnfreezeCallBack (void)
	MIA clock unfreeze notification. Internal.
void	keyscan_enableInterrupt (void)
	Enables the interrupts from Keyscan HW. More...
void	keyscan_disableInterrupt (void)
	Disables interrupts from the keyscan HW block.
void	keyscan_ksInterrupt (void)
	Thread context interrupt handler. Internal.
void	keyscan_restoreActivity (void)
	Reenables keyscan after a soft power up. Internal.
void	keyscan_clearKeysPressedCount (void)
	Clear the count of unmatched key down events. Internal.
UINT8	keyscan_getKeysPressedCount (void)
	Get count of unmatched key down events.
void	keyscan_enableGhostDetection (BOOL32 enable)
	Enable/disable keyscan ghost detection.
void	keyscan_hwResetOnce (void)
	Soft Reset the keyscan HW once.
void	keyscan_initHW (void)
	Initialize the keyscan HE. Internal.
void	keyscan_configGpios (void)
	Configure the GPIOs used by the keyscan HW based on keyscan config.
void	keyscan_getEventsFromHWFifo (void)
	Retrieve events from the HW fifo and places them in the FW fifo. More...

Detailed Description

Enumeration Type Documentation

anonymous enum

Defines the standard keyscan driver.

The standard keyscan driver provides the status and control for the keyscan driver. It provides the keyEvents to the interface, maintains the queue behind it. It also supports keyscanning turning on or off.No event.

Enumerator
EVENT_NONE	Keycode value if no key is pressed.

Function Documentation

void keyscan_enableEventDetection

(

void

)

Configures the interrupt source from Keyscan HW and enables event detection.

A callback function using keyscan_registerForEventNotification() must have been registered prior to enabling event detection.

void keyscan_enableInterrupt

(

void

)

Enables the interrupts from Keyscan HW.

Note that Keyscan interrupt must be configured before being used enabled, else, interrupts will not fire.

BOOL32 keyscan_eventsPending

(

void

)

Check if there are any pending key events.

Returns

TRUE if there are pending key events, FALSE otherwise

void keyscan_getEventsFromHWFifo

(

void

)

Retrieve events from the HW fifo and places them in the FW fifo.

End of scan cycle events are inserted to separate keys detected in separate scans. This function assumes that MIA clock is frozen.

BOOL32 keyscan_getNextEvent

(

KeyEvent *

event

)

Get next key event.

Parameters

event

pointer to where the event should be stored

Returns

TRUE if an event is returned, FALSE otherwise

void keyscan_init

(

void

)

Keyscan driver initialization function.

This allocates space for the FW FIFO for key events and initializes the keyscan HW. This function should be invoked only once before using any keyscan services. Subsequent invocations will invoke undefined behavior. Keyscan driver must be initialized AFTER mia driver is initialized.

void keyscan_miaFreezeCallBack

(

void

)

MIA clock freeze notification.

Retrieves any pending events from the HW fifo. Internal.

void keyscan_registerForEventNotification	(	void(*)(void *)	userfn,
		void *	userdata
	)

Register for notification of changes.

Once registered, you CAN NOT UNREGISTER; registration is meant to be a startup activity

Parameters

userfn	points to the function to call when the interrupt comes and matches one of the masks (if you pass a method, it must be static). The function does not need to clear the interrupt status; this will be done by KeyscanDriver::lhlInterrupt(). The function will be called ONCE per interrupt.
userdata	will be passed back to userfn as-is; it can be used to carry the "this", for example

void keyscan_turnOn

(

void

)

Enabled keyscanning and and any associated wakeup functionality.

Should only be used if keyscanning was disabled via turnOff()