mbed library sources
Dependents: frdm_kl05z_gpio_test
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Diff: targets/hal/TARGET_NXP/TARGET_LPC11XX_11CXX/gpio_irq_api.c
- Revision:
- 30:91c1d09ada54
- Child:
- 35:371630885ad6
diff -r 6ac4027eff2b -r 91c1d09ada54 targets/hal/TARGET_NXP/TARGET_LPC11XX_11CXX/gpio_irq_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_NXP/TARGET_LPC11XX_11CXX/gpio_irq_api.c Wed Sep 25 10:30:04 2013 +0100 @@ -0,0 +1,176 @@ +/* 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 "cmsis.h" +#include "gpio_irq_api.h" +#include "error.h" +#include "gpio_api.h" + +// The chip is capable of 42 GPIO interrupts. +// PIO0_0..PIO0_11, PIO1_0..PIO1_11, PIO2_0..PIO2_11, PIO3_0..PIO3_5 +#define CHANNEL_NUM 42 + +static uint32_t channel_ids[CHANNEL_NUM] = {0}; +static gpio_irq_handler irq_handler; + +static inline int numofbits(uint32_t bits) +{ + // Count number of bits + bits = (bits & 0x55555555) + (bits >> 1 & 0x55555555); + bits = (bits & 0x33333333) + (bits >> 2 & 0x33333333); + bits = (bits & 0x0f0f0f0f) + (bits >> 4 & 0x0f0f0f0f); + bits = (bits & 0x00ff00ff) + (bits >> 8 & 0x00ff00ff); + return (bits & 0x0000ffff) + (bits >>16 & 0x0000ffff); +} + +static inline void handle_interrupt_in(uint32_t port) { + // Find out whether the interrupt has been triggered by a high or low value... + // As the LPC1114 doesn't have a specific register for this, we'll just have to read + // the level of the pin as if it were just a normal input... + + uint32_t channel; + + // Get the number of the pin being used and the port typedef + LPC_GPIO_TypeDef *port_reg = ((LPC_GPIO_TypeDef *) (LPC_GPIO0_BASE + (port * 0x10000))); + + // Get index of function table from Mask Interrupt Status register + channel = numofbits(port_reg->MIS - 1); + + if (port_reg->MIS & port_reg->IBE) { + // both edge, read the level of pin + if ((port_reg->DATA & port_reg->MIS) != 0) + irq_handler(channel_ids[channel], IRQ_RISE); + else + irq_handler(channel_ids[channel], IRQ_FALL); + } + else if (port_reg->MIS & port_reg->IEV) { + irq_handler(channel_ids[channel], IRQ_RISE); + } + else { + irq_handler(channel_ids[channel], IRQ_FALL); + } + + // Clear the interrupt... + port_reg->IC = port_reg->MIS; +} + +void gpio_irq0(void) {handle_interrupt_in(0);} +void gpio_irq1(void) {handle_interrupt_in(1);} +void gpio_irq2(void) {handle_interrupt_in(2);} +void gpio_irq3(void) {handle_interrupt_in(3);} + +int gpio_irq_init(gpio_irq_t *obj, PinName pin, gpio_irq_handler handler, uint32_t id) { + int channel; + uint32_t port_num; + + if (pin == NC) return -1; + + // Firstly, we'll put some data in *obj so we can keep track of stuff. + obj->pin = pin; + + // Set the handler to be the pointer at the top... + irq_handler = handler; + + // Which port are we using? + port_num = ((pin & 0xF000) >> PORT_SHIFT); + + switch (port_num) { + case 0: + NVIC_SetVector(EINT0_IRQn, (uint32_t)gpio_irq0); + NVIC_EnableIRQ(EINT0_IRQn); + break; + case 1: + NVIC_SetVector(EINT1_IRQn, (uint32_t)gpio_irq1); + NVIC_EnableIRQ(EINT1_IRQn); + break; + case 2: + NVIC_SetVector(EINT2_IRQn, (uint32_t)gpio_irq2); + NVIC_EnableIRQ(EINT2_IRQn); + break; + case 3: + NVIC_SetVector(EINT3_IRQn, (uint32_t)gpio_irq3); + NVIC_EnableIRQ(EINT3_IRQn); + break; + default: + return -1; + } + + // Generate index of function pointer table + // PIO0_0 - PIO0_11 : 0..11 + // PIO1_0 - PIO1_11 : 12..23 + // PIO2_0 - PIO2_11 : 24..35 + // PIO3_0 - PIO3_5 : 36..41 + channel = (port_num * 12) + ((pin & 0x0F00) >> PIN_SHIFT); + + channel_ids[channel] = id; + obj->ch = channel; + + 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) { + // Firstly, check if there is an existing event stored... + + LPC_GPIO_TypeDef *port_reg = ((LPC_GPIO_TypeDef *) (LPC_GPIO0_BASE + (((obj->pin & 0xF000) >> PORT_SHIFT) * 0x10000))); + + // Need to get the pin number of the pin, not the value of the enum + uint32_t pin_num = (1 << ((obj->pin & 0x0f00) >> PIN_SHIFT)); + + // Clear + port_reg->IC |= pin_num; + + // Make it edge sensitive. + port_reg->IS &= ~pin_num; + + if ( (port_reg->IE & pin_num) != 0) { + // We have an event. + // Enable both edge interrupts. + + if (enable) { + port_reg->IBE |= pin_num; + port_reg->IE |= pin_num; + } + else { + // These all need to be opposite, to reenable the other one. + port_reg->IBE &= ~pin_num; + + if (event == IRQ_RISE) + port_reg->IEV &= ~pin_num; + else + port_reg->IEV |= pin_num; + + port_reg->IE |= pin_num; + } + } + else { + // One edge + port_reg->IBE &= ~pin_num; + // Rising/falling? + if (event == IRQ_RISE) + port_reg->IEV |= pin_num; + else + port_reg->IEV &= ~pin_num; + + if (enable) { + port_reg->IE |= pin_num; + } + } + +}