From 6dea259ea2dd0afc4b610961e211d77460cfd0c6 Mon Sep 17 00:00:00 2001 From: inmarket Date: Wed, 9 Jul 2014 18:47:59 +1000 Subject: Example added for FreeRTOS on Raspberry Pi --- .../RaspberryPi/example-FreeRTOS/Drivers/gpio.c | 134 +++++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 boards/base/RaspberryPi/example-FreeRTOS/Drivers/gpio.c (limited to 'boards/base/RaspberryPi/example-FreeRTOS/Drivers/gpio.c') diff --git a/boards/base/RaspberryPi/example-FreeRTOS/Drivers/gpio.c b/boards/base/RaspberryPi/example-FreeRTOS/Drivers/gpio.c new file mode 100644 index 00000000..485de897 --- /dev/null +++ b/boards/base/RaspberryPi/example-FreeRTOS/Drivers/gpio.c @@ -0,0 +1,134 @@ +/** + * Quick and very Dirty GPIO API. + * + **/ + +#include "gpio.h" + +typedef struct { + unsigned long GPFSEL[6]; ///< Function selection registers. + unsigned long Reserved_1; + unsigned long GPSET[2]; + unsigned long Reserved_2; + unsigned long GPCLR[2]; + unsigned long Reserved_3; + unsigned long GPLEV[2]; + unsigned long Reserved_4; + unsigned long GPEDS[2]; + unsigned long Reserved_5; + unsigned long GPREN[2]; + unsigned long Reserved_6; + unsigned long GPFEN[2]; + unsigned long Reserved_7; + unsigned long GPHEN[2]; + unsigned long Reserved_8; + unsigned long GPLEN[2]; + unsigned long Reserved_9; + unsigned long GPAREN[2]; + unsigned long Reserved_A; + unsigned long GPAFEN[2]; + unsigned long Reserved_B; + unsigned long GPPUD[1]; + unsigned long GPPUDCLK[2]; + //Ignoring the reserved and test bytes +} BCM2835_GPIO_REGS; + +volatile BCM2835_GPIO_REGS * const pRegs = (BCM2835_GPIO_REGS *) (0x20200000); + + +void SetGpioFunction(unsigned int pinNum, unsigned int funcNum) { + + int offset = pinNum / 10; + + unsigned long val = pRegs->GPFSEL[offset]; // Read in the original register value. + + int item = pinNum % 10; + val &= ~(0x7 << (item * 3)); + val |= ((funcNum & 0x7) << (item * 3)); + pRegs->GPFSEL[offset] = val; +} + +void SetGpioDirection(unsigned int pinNum, enum GPIO_DIR dir) { + SetGpioFunction(pinNum,dir); +} + +void SetGpio(unsigned int pinNum, unsigned int pinVal) { + unsigned long offset=pinNum/32; + unsigned long mask=(1<<(pinNum%32)); + + if(pinVal) { + pRegs->GPSET[offset]|=mask; + } else { + pRegs->GPCLR[offset]|=mask; + } +} + +int ReadGpio(unsigned int pinNum) { + return ((pRegs->GPLEV[pinNum/32])>>(pinNum%32))&1; +} + +void EnableGpioDetect(unsigned int pinNum, enum DETECT_TYPE type) +{ + unsigned long mask=(1<GPREN[offset]|=mask; + break; + case DETECT_FALLING: + pRegs->GPFEN[offset]|=mask; + break; + case DETECT_HIGH: + pRegs->GPHEN[offset]|=mask; + break; + case DETECT_LOW: + pRegs->GPLEN[offset]|=mask; + break; + case DETECT_RISING_ASYNC: + pRegs->GPAREN[offset]|=mask; + break; + case DETECT_FALLING_ASYNC: + pRegs->GPAFEN[offset]|=mask; + break; + case DETECT_NONE: + break; + } +} + +void DisableGpioDetect(unsigned int pinNum, enum DETECT_TYPE type) +{ + unsigned long mask=~(1<<(pinNum%32)); + unsigned long offset=pinNum/32; + + switch(type) { + case DETECT_RISING: + pRegs->GPREN[offset]&=mask; + break; + case DETECT_FALLING: + pRegs->GPFEN[offset]&=mask; + break; + case DETECT_HIGH: + pRegs->GPHEN[offset]&=mask; + break; + case DETECT_LOW: + pRegs->GPLEN[offset]&=mask; + break; + case DETECT_RISING_ASYNC: + pRegs->GPAREN[offset]&=mask; + break; + case DETECT_FALLING_ASYNC: + pRegs->GPAFEN[offset]&=mask; + break; + case DETECT_NONE: + break; + } +} + +void ClearGpioInterrupt(unsigned int pinNum) +{ + unsigned long mask=(1<<(pinNum%32)); + unsigned long offset=pinNum/32; + + pRegs->GPEDS[offset]=mask; +} -- cgit v1.2.3