Mouse code for the MacroRat
Diff: mbed-dev/targets/TARGET_NXP/TARGET_LPC176X/gpio_irq_api.c
- Revision:
- 18:6a4db94011d3
diff -r f713758f6238 -r 6a4db94011d3 mbed-dev/targets/TARGET_NXP/TARGET_LPC176X/gpio_irq_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-dev/targets/TARGET_NXP/TARGET_LPC176X/gpio_irq_api.c Sun May 14 23:18:57 2017 +0000 @@ -0,0 +1,161 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#include <stddef.h> + +#include "gpio_irq_api.h" +#include "mbed_error.h" +#include "cmsis.h" + +#define CHANNEL_NUM 48 + +static uint32_t channel_ids[CHANNEL_NUM] = {0}; +static gpio_irq_handler irq_handler; + +static void handle_interrupt_in(void) { + // Read in all current interrupt registers. We do this once as the + // GPIO interrupt registers are on the APB bus, and this is slow. + uint32_t rise0 = LPC_GPIOINT->IO0IntStatR; + uint32_t fall0 = LPC_GPIOINT->IO0IntStatF; + uint32_t rise2 = LPC_GPIOINT->IO2IntStatR; + uint32_t fall2 = LPC_GPIOINT->IO2IntStatF; + uint8_t bitloc; + + while(rise0 > 0) { //Continue as long as there are interrupts pending + bitloc = 31 - __CLZ(rise0); //CLZ returns number of leading zeros, 31 minus that is location of first pending interrupt + if (channel_ids[bitloc] != 0) + irq_handler(channel_ids[bitloc], IRQ_RISE); //Run that interrupt + + //Both clear the interrupt with clear register, and remove it from our local copy of the interrupt pending register + LPC_GPIOINT->IO0IntClr = 1 << bitloc; + rise0 -= 1<<bitloc; + } + + while(fall0 > 0) { //Continue as long as there are interrupts pending + bitloc = 31 - __CLZ(fall0); //CLZ returns number of leading zeros, 31 minus that is location of first pending interrupt + if (channel_ids[bitloc] != 0) + irq_handler(channel_ids[bitloc], IRQ_FALL); //Run that interrupt + + //Both clear the interrupt with clear register, and remove it from our local copy of the interrupt pending register + LPC_GPIOINT->IO0IntClr = 1 << bitloc; + fall0 -= 1<<bitloc; + } + + //Same for port 2, only we need to watch the channel_index + while(rise2 > 0) { //Continue as long as there are interrupts pending + bitloc = 31 - __CLZ(rise2); //CLZ returns number of leading zeros, 31 minus that is location of first pending interrupt + + if (bitloc < 16) //Not sure if this is actually needed + if (channel_ids[bitloc+32] != 0) + irq_handler(channel_ids[bitloc+32], IRQ_RISE); //Run that interrupt + + //Both clear the interrupt with clear register, and remove it from our local copy of the interrupt pending register + LPC_GPIOINT->IO2IntClr = 1 << bitloc; + rise2 -= 1<<bitloc; + } + + while(fall2 > 0) { //Continue as long as there are interrupts pending + bitloc = 31 - __CLZ(fall2); //CLZ returns number of leading zeros, 31 minus that is location of first pending interrupt + + if (bitloc < 16) //Not sure if this is actually needed + if (channel_ids[bitloc+32] != 0) + irq_handler(channel_ids[bitloc+32], IRQ_FALL); //Run that interrupt + + //Both clear the interrupt with clear register, and remove it from our local copy of the interrupt pending register + LPC_GPIOINT->IO2IntClr = 1 << bitloc; + fall2 -= 1<<bitloc; + } +} + +int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id) { + if (pin == NC) return -1; + + irq_handler = handler; + + obj->port = (int)pin & ~0x1F; + obj->pin = (int)pin & 0x1F; + + // Interrupts available only on GPIO0 and GPIO2 + if (obj->port != LPC_GPIO0_BASE && obj->port != LPC_GPIO2_BASE) { + error("pins on this port cannot generate interrupts"); + } + + // put us in the interrupt table + int index = (obj->port == LPC_GPIO0_BASE) ? obj->pin : obj->pin + 32; + channel_ids[index] = id; + obj->ch = index; + + NVIC_SetVector(EINT3_IRQn, (uint32_t)handle_interrupt_in); + NVIC_EnableIRQ(EINT3_IRQn); + return 0; +} + +void gpio_irq_free(gpio_irq_t *obj) { + channel_ids[obj->ch] = 0; +} + +void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable) { + // ensure nothing is pending + switch (obj->port) { + case LPC_GPIO0_BASE: LPC_GPIOINT->IO0IntClr = 1 << obj->pin; break; + case LPC_GPIO2_BASE: LPC_GPIOINT->IO2IntClr = 1 << obj->pin; break; + } + + // enable the pin interrupt + if (event == IRQ_RISE) { + switch (obj->port) { + case LPC_GPIO0_BASE: + if (enable) { + LPC_GPIOINT->IO0IntEnR |= 1 << obj->pin; + } else { + LPC_GPIOINT->IO0IntEnR &= ~(1 << obj->pin); + } + break; + case LPC_GPIO2_BASE: + if (enable) { + LPC_GPIOINT->IO2IntEnR |= 1 << obj->pin; + } else { + LPC_GPIOINT->IO2IntEnR &= ~(1 << obj->pin); + } + break; + } + } else { + switch (obj->port) { + case LPC_GPIO0_BASE: + if (enable) { + LPC_GPIOINT->IO0IntEnF |= 1 << obj->pin; + } else { + LPC_GPIOINT->IO0IntEnF &= ~(1 << obj->pin); + } + break; + case LPC_GPIO2_BASE: + if (enable) { + LPC_GPIOINT->IO2IntEnF |= 1 << obj->pin; + } else { + LPC_GPIOINT->IO2IntEnF &= ~(1 << obj->pin); + } + break; + } + } +} + +void gpio_irq_enable(gpio_irq_t *obj) { + NVIC_EnableIRQ(EINT3_IRQn); +} + +void gpio_irq_disable(gpio_irq_t *obj) { + NVIC_DisableIRQ(EINT3_IRQn); +} +