m2mb_gpio.h File Reference

GPIO library implementation. More...

Go to the source code of this file.

Macros
#define	NULL   0
#define	M2MB_GPIO_ISR_IS_ENABLED   1
	ME910 products have 10 GPIOs.
#define	M2MB_GPIO_ISR_IS_DISABLED   0
#define	m2mb_gpio_multi_ioctl_(fd, args...)   m2mb_gpio_multi_ioctl( fd, CMDS_ARGS( args ) )

Typedefs
typedef void(*	m2mb_gpio_intr_callback) (UINT32 fd, void *userdata)
	GPIO interrupt callback function definition. More...

Enumerations
enum	M2MB_GPIO_IOCTL_REQUEST_E {   M2MB_GPIO_IOCTL_SET_DIR, M2MB_GPIO_IOCTL_GET_DIR, M2MB_GPIO_IOCTL_SET_PULL, M2MB_GPIO_IOCTL_GET_PULL,   M2MB_GPIO_IOCTL_SET_DRIVE, M2MB_GPIO_IOCTL_GET_DRIVE, M2MB_GPIO_IOCTL_INIT_INTR, M2MB_GPIO_IOCTL_DEINIT_INTR,   M2MB_GPIO_IOCTL_SET_INTR_TYPE, M2MB_GPIO_IOCTL_GET_INTR_TYPE, M2MB_GPIO_IOCTL_SET_INTR_CB, M2MB_GPIO_IOCTL_GET_INTR_CB,   M2MB_GPIO_IOCTL_SET_INTR_ARG, M2MB_GPIO_IOCTL_GET_INTR_ARG, M2MB_GPIO_IOCTL_SET_INTR_TRIGGER, M2MB_GPIO_IOCTL_GET_INTR_TRIGGER,   M2MB_GPIO_IOCTL_SET_ISR_COUNTER, M2MB_GPIO_IOCTL_GET_ISR_COUNTER, M2MB_GPIO_IOCTL_GET_GPIO_N, M2MB_GPIO_IOCTL_GET_INTR }
enum	M2MB_GPIO_DIRECTION_E { M2MB_GPIO_MODE_INPUT = 0, M2MB_GPIO_MODE_OUTPUT = 1 }
	enum used for gpio direction More...
enum	M2MB_GPIO_TRIGGER_E { M2MB_GPIO_INTR_POSEDGE, M2MB_GPIO_INTR_NEGEDGE, M2MB_GPIO_INTR_ANYEDGE }
enum	M2MB_GPIO_PULL_MODE_E { M2MB_GPIO_NO_PULL, M2MB_GPIO_PULL_DOWN, M2MB_GPIO_PULL_KEEPER, M2MB_GPIO_PULL_UP }
enum	M2MB_GPIO_DRIVE_E { M2MB_GPIO_LOW_DRIVE = 0, M2MB_GPIO_MEDIUM_DRIVE = 0x1, M2MB_GPIO_HIGH_DRIVE = 0x2 }
	GPIO pin drive strength. More...
enum	M2MB_GPIO_VALUE_E { M2MB_GPIO_LOW_VALUE = 0, M2MB_GPIO_HIGH_VALUE = 1 }
	GPIO output state specification. More...
enum	M2M_GPIO_INTR_TYPE_E { INTR_CB_SET = 0, INTR_COUNTER_SET, INTR_COUNTER_SET_HP }
	GPIO ISR type: callback or counter. More...

Functions
INT32	m2mb_gpio_open (const CHAR *path, INT32 flags,...)
	open a GPIO device More...
INT32	m2mb_gpio_close (INT32 fd)
	close a GPIO device More...
INT32	m2mb_gpio_ioctl (INT32 fd, INT32 cmd, UINT32 arg)
	configure a GPIO device More...
INT32	m2mb_gpio_multi_ioctl (INT32 fd, UINT8 nCmds,...)
	: multiple configuration of a GPIO device. More...
INT32	m2mb_gpio_read (INT32 fd, M2MB_GPIO_VALUE_E *value)
	Reads the state of a GPIO pin. More...
INT32	m2mb_gpio_write (INT32 fd, M2MB_GPIO_VALUE_E value)
	write the value of a GPIO device More...

Detailed Description

GPIO library implementation.

m2m_generic/common/m2mb_inc/m2mb_gpio.h

The following functions are implemented: m2mb_gpio_ioctl m2mb_gpio_multi_ioctl m2mb_gpio_open m2mb_gpio_read m2mb_gpio_write m2mb_gpio_close

@notes Dependencies: m2mb_types.h

Author

Morgan Deidda

@changes Dino Apostoli, Alessandro Papagno, Mathan Babu

Date

31/08/2017

Typedef Documentation

m2mb_gpio_intr_callback

typedef void( * m2mb_gpio_intr_callback) (UINT32 fd, void *userdata)

GPIO interrupt callback function definition.

GPIO interrupt clients will pass a function pointer of this format in M2MB_GPIO_CFG_T callback function

Enumeration Type Documentation

M2M_GPIO_INTR_TYPE_E

enum M2M_GPIO_INTR_TYPE_E

GPIO ISR type: callback or counter.

Enumerator
INTR_CB_SET	Interrupt set with a callback function.
INTR_COUNTER_SET	Interrupt set a counter for interrupt and no callback, counter has UINT32 size, is auto reset to 0 in case of overflow
INTR_COUNTER_SET_HP	Interrupt pulse counter high performance, for pulse with high repetition rate (typically about > 3 kHz, to be verified). For low repetition rate, also counting on callback or INTR_COUNTER_SET type can be satisfactory. With HP mode, power consumption can increase, so it is suggested to enable it only during one shot measure (e.g measure from pulse counter sensor) than disable it. If one gpio is set and enabled as HP, it promotes all isrs running in counting mode to HP without changing their attributes. When the last configured HP is disabled, all running isrs recover their initial behavior.

M2MB_GPIO_DIRECTION_E

enum M2MB_GPIO_DIRECTION_E

enum used for gpio direction

Enumerator
M2MB_GPIO_MODE_INPUT	GPIO mode : input
M2MB_GPIO_MODE_OUTPUT	GPIO mode : output

M2MB_GPIO_DRIVE_E

enum M2MB_GPIO_DRIVE_E

GPIO pin drive strength.

This enumeration specifies the drive strength to use when specifying the configuration of a GPIO pin.

Enumerator
M2MB_GPIO_LOW_DRIVE	Specify a low drive.
M2MB_GPIO_MEDIUM_DRIVE	Specify a medium drive.
M2MB_GPIO_HIGH_DRIVE	Specify a high drive.

M2MB_GPIO_IOCTL_REQUEST_E

enum M2MB_GPIO_IOCTL_REQUEST_E

Enumerator
M2MB_GPIO_IOCTL_SET_DIR	Set gpio device direction configuration
M2MB_GPIO_IOCTL_GET_DIR	Get gpio device direction configuration
M2MB_GPIO_IOCTL_SET_PULL	Set gpio device pull configuration
M2MB_GPIO_IOCTL_GET_PULL	Get gpio device pull configuration
M2MB_GPIO_IOCTL_SET_DRIVE	Set gpio pin drive strength
M2MB_GPIO_IOCTL_GET_DRIVE	Get gpio pin drive strength
M2MB_GPIO_IOCTL_INIT_INTR	Registers a callback/counter for a GPIO interrupt
M2MB_GPIO_IOCTL_DEINIT_INTR	Deregisters a callback/counter Interrupt service
M2MB_GPIO_IOCTL_SET_INTR_TYPE	Set the interrupt type: INTR_CB_SET, INTR_COUNTER_SET or INTR_COUNTER_SET_HP, see M2M_GPIO_INTR_TYPE_E
M2MB_GPIO_IOCTL_GET_INTR_TYPE	Get the interrupt type: INTR_CB_SET or INTR_COUNTER_SET
M2MB_GPIO_IOCTL_SET_INTR_CB	Set the callback function for the interrupt service
M2MB_GPIO_IOCTL_GET_INTR_CB	Get the callback function used for the interrupt service
M2MB_GPIO_IOCTL_SET_INTR_ARG	Argument to be passed in the callback function of the interrupt
M2MB_GPIO_IOCTL_GET_INTR_ARG	Get the Argument of the callback function of the interrupt
M2MB_GPIO_IOCTL_SET_INTR_TRIGGER	Set trigger. N.B.Can dynamically sets the trigger type of a registered GPIO interrupt
M2MB_GPIO_IOCTL_GET_INTR_TRIGGER	Get the trigger type of a registered GPIO interrupt, as in M2MB_GPIO_TRIGGER_E
M2MB_GPIO_IOCTL_SET_ISR_COUNTER	Set ISR interrupt counter value
M2MB_GPIO_IOCTL_GET_ISR_COUNTER	Read ISR interrupt counter value, counter has UINT32 size, is auto reset to 0 in case of overflow
M2MB_GPIO_IOCTL_GET_GPIO_N	Get the gpio number or pin for file descriptor
M2MB_GPIO_IOCTL_GET_INTR	Get the INTR status, e.g. M2MB_GPIO_ISR_IS_ENABLED if enabled

M2MB_GPIO_PULL_MODE_E

enum M2MB_GPIO_PULL_MODE_E

Enumerator
M2MB_GPIO_NO_PULL	Specify no pull
M2MB_GPIO_PULL_DOWN	Gpio pull down
M2MB_GPIO_PULL_KEEPER	Keep the GPIO as it is
M2MB_GPIO_PULL_UP	Gpio pull up

M2MB_GPIO_TRIGGER_E

enum M2MB_GPIO_TRIGGER_E

Enumerator
M2MB_GPIO_INTR_POSEDGE	Rising edge triggered, to trigger when the pin goes from low to high,
M2MB_GPIO_INTR_NEGEDGE	Falling edge triggered.
M2MB_GPIO_INTR_ANYEDGE	Dual edge triggered, to trigger the interrupt whenever the pin changes value

M2MB_GPIO_VALUE_E

enum M2MB_GPIO_VALUE_E

GPIO output state specification.

Enumerator
M2MB_GPIO_LOW_VALUE	Drive the output LOW.
M2MB_GPIO_HIGH_VALUE	Drive the output HIGH.

Function Documentation

m2mb_gpio_close()

INT32 m2mb_gpio_close

(

INT32

fd

)

close a GPIO device

This function close a GPIO device

Parameters

[in]

fd

file descriptor returned by m2mb_gpio_open

Returns

0 on SUCCESS -1 on FAILURE

m2mb_gpio_ioctl()

INT32 m2mb_gpio_ioctl	(	INT32	fd,
		INT32	cmd,
		UINT32	arg
	)

configure a GPIO device

This function configure a GPIO using the M2MB_GPIO_IOCTL_REQUEST_E enum

Parameters

[in]	fd	file descriptor returned by m2mb_gpio_open
[in]	cmd	required operation (see M2MB_GPIO_IOCTL_REQUEST_E)
[in]	arg	pointer to the value to set

Returns

0 on SUCCESS -1 on FAILURE

Note

In order to use interrupts it is mandatory to initialize the interrupt with M2MB_GPIO_IOCTL_INIT_INTR and M2MB_GPIO_IOCTL_INIT_INTR must be the last m2mb_gpio_ioctl() call

Example

example of usage
INT32  ret;
fd = m2mb_gpio_open( "/dev/GPIO1", 0 );
 
if( fd != -1 )
{
  ret = m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_DIR, M2MB_GPIO_MODE_INPUT );
  if ( ret == -1 )
    return ;
 
  ret = m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_PULL, M2MB_GPIO_PULL_UP );
  ret = m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_DRIVE, M2MB_GPIO_MEDIUM_DRIVE );
}

example of usage for a interrupt callback:
static void myUptrigg_callbk(UINT32 fd,  void *userdata )
{
  ....
}
 
.....
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_INTR_TRIGGER,  M2MB_GPIO_INTR_POSEDGE );
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_INTR_ARG,  (UINT32)str_gpio );
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_INTR_CB,  (UINT32)myUptrigg_callbk );
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_INTR_TYPE,  INTR_CB_SET );
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_SET_ISR_COUNTER,  0 );
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_INIT_INTR,  NULL );
 
//In order to use interrupts it is mandatory to initialize the interrupt with M2MB_GPIO_IOCTL_INIT_INTR
//M2MB_GPIO_IOCTL_INIT_INTR must be the last m2mb_gpio_ioctl

example of usage for get data: Must be used with the reference or pointer
 
M2MB_GPIO_DIRECTION_E dir;
M2MB_GPIO_PULL_MODE_E pull;
 
 
ret = m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_GET_DIR, (UINT32)&dir );
if( ret )
  ......
 
ret = m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_GET_PULL, (UINT32)&pull );
 
if( ret )
  ......
 
@code
example of usage for set and get interrupt argument
CHAR str_test[] = "hello";
CHAR *ptr_str;
 
m2mb_gpio_ioctl(fd2, M2MB_GPIO_IOCTL_SET_INTR_ARG, (UINT32)str_test);
ret = m2mb_gpio_ioctl(fd2, M2MB_GPIO_IOCTL_GET_INTR_ARG, (UINT32)&ptr_str);

m2mb_gpio_multi_ioctl()

INT32 m2mb_gpio_multi_ioctl	(	INT32	fd,
		UINT8	nCmds,
			...
	)

: multiple configuration of a GPIO device.

allow a multiple configuration of a GPIO device. Can not be used in order to get data. In order to use interrupts it is mandatory to initialize the interrupt with M2MB_GPIO_IOCTL_INIT_INTR

Parameters

[in]	fd	file descriptor returned by m2mb_gpio_open
[in]	nCmds	number of commands to be issued at once
[in]	...	variable inputs, N cmds (see M2MB_GPIO_IOCTL_REQUEST_E) followed by N arguments for their respective issued commands. CMDS(...) and CMDS_ARGS(...) macro can be used to better insert cmd and parameters and to better control right insertion

Returns

0 on SUCCESS -1 on FAILURE

Example

example of usage for PMM:
ret =  m2mb_gpio_multi_ioctl( fd1, CMDS_ARGS( M2MB_GPIO_IOCTL_SET_DIR, M2MB_GPIO_MODE_OUTPUT,
                                M2MB_GPIO_IOCTL_SET_PULL, M2MB_GPIO_PULL_UP,
                                M2MB_GPIO_IOCTL_SET_DRIVE, M2MB_GPIO_MEDIUM_DRIVE ) );
if ( ret )
{
  m2mb_trace_printf(M2MB_TC_M2M_USER, M2MB_TL_ERROR, "GPIO1 FAIL" );
}

example of usage for a interrupt callback:
INT32 ret;
 
ret =  m2mb_gpio_multi_ioctl( fd1, CMDS_ARGS( M2MB_GPIO_IOCTL_INIT_INTR, NULL,
                                    M2MB_GPIO_IOCTL_SET_INTR_TYPE, INTR_CB_SET,
                                    M2MB_GPIO_IOCTL_SET_INTR_CB, myUptrigg_callbk,
                                    M2MB_GPIO_IOCTL_SET_INTR_ARG, str_gpio,
                                    M2MB_GPIO_IOCTL_SET_INTR_TRIGGER, M2MB_GPIO_INTR_POSEDGE
                                ) );
 
if( ret == -1 )
{
  m2mb_trace_printf(M2MB_TC_M2M_USER, M2MB_TL_ERROR, "GPIO1 - FAIL" );
}

example of usage for high performance interrupt pulse counter
 
m2mb_gpio_multi_ioctl(gpioFd, CMDS_ARGS(
      M2MB_GPIO_IOCTL_SET_DIR, M2MB_GPIO_MODE_INPUT,
      M2MB_GPIO_IOCTL_SET_PULL, M2MB_GPIO_NO_PULL,
      M2MB_GPIO_IOCTL_SET_DRIVE, M2MB_GPIO_HIGH_DRIVE,
      M2MB_GPIO_IOCTL_SET_INTR_TRIGGER, M2MB_GPIO_INTR_NEGEDGE,
      M2MB_GPIO_IOCTL_SET_INTR_TYPE, INTR_COUNTER_SET_HP,
      M2MB_GPIO_IOCTL_SET_ISR_COUNTER, (UINT32) 0
    ));
 
//register interrupt as INTR_COUNTER_SET_HP
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_INIT_INTR, NULL );
 
//performs needed measure from example from sensor
 
//deregister interrupt
m2mb_gpio_ioctl( fd, M2MB_GPIO_IOCTL_DEINIT_INTR, NULL );

m2mb_gpio_open()

INT32 m2mb_gpio_open	(	const CHAR *	path,
		INT32	flags,
			...
	)

open a GPIO device

This function open a GPIO device

Parameters

[in]	path	the path has a string of this type: /dev/GPIO# where # is in decimal format
[in]	flags	currently unused

Returns

file descriptor on SUCCESS -1 on FAILURE

Example

fd = m2mb_gpio_open( "/dev/GPIO5", 0 );

m2mb_gpio_read()

INT32 m2mb_gpio_read	(	INT32	fd,
		M2MB_GPIO_VALUE_E *	value
	)

Reads the state of a GPIO pin.

Reads the state of a GPIO pin, used only for M2MB_GPIO_MODE_INPUT

Parameters

[in]	fd	file descriptor returned by m2mb_gpio_open
[out]	value	get the M2MB_GPIO_VALUE_E LOW or HIGH

Returns

0 on SUCCESS -1 on FAILURE

Example

M2MB_GPIO_VALUE_E value_read;
 
ret = m2mb_gpio_read(fd, &value_read );

m2mb_gpio_write()

INT32 m2mb_gpio_write	(	INT32	fd,
		M2MB_GPIO_VALUE_E	value
	)

write the value of a GPIO device

write the value high or low to a GPIO device, used only for M2MB_GPIO_MODE_OUTPUT

Parameters

[in]	fd	file descriptor returned by m2mb_gpio_open
[in]	value	set high or low

Returns

0 on SUCCESS -1 on FAILURE

ret = m2mb_gpio_write( fd, M2MB_GPIO_LOW_VALUE );