Diff: targets/TARGET_NXP/TARGET_LPC11UXX/gpio_irq_api.c

Revision:

149:156823d33999

Parent:

144:ef7eb2e8f9f7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NXP/TARGET_LPC11UXX/gpio_irq_api.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,141 @@
+/* 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 "mbed_error.h"
+
+#define CHANNEL_NUM    8
+#define LPC_GPIO_X LPC_GPIO_PIN_INT
+#define PININT_IRQ 0
+
+static uint32_t channel_ids[CHANNEL_NUM] = {0};
+static gpio_irq_handler irq_handler;
+
+static inline void handle_interrupt_in(uint32_t channel) {
+    uint32_t ch_bit = (1 << channel);
+    // Return immediately if:
+    //   * The interrupt was already served
+    //   * There is no user handler
+    //   * It is a level interrupt, not an edge interrupt
+    if ( ((LPC_GPIO_X->IST & ch_bit) == 0) ||
+         (channel_ids[channel] == 0      ) ||
+         (LPC_GPIO_X->ISEL & ch_bit      ) ) return;
+
+    if ((LPC_GPIO_X->IENR & ch_bit) && (LPC_GPIO_X->RISE & ch_bit)) {
+        irq_handler(channel_ids[channel], IRQ_RISE);
+        LPC_GPIO_X->RISE = ch_bit;
+    }
+    if ((LPC_GPIO_X->IENF & ch_bit) && (LPC_GPIO_X->FALL & ch_bit)) {
+        irq_handler(channel_ids[channel], IRQ_FALL);
+    }
+    LPC_GPIO_X->IST = ch_bit;
+}
+
+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);}
+void gpio_irq4(void) {handle_interrupt_in(4);}
+void gpio_irq5(void) {handle_interrupt_in(5);}
+void gpio_irq6(void) {handle_interrupt_in(6);}
+void gpio_irq7(void) {handle_interrupt_in(7);}
+
+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;
+    
+    int found_free_channel = 0;
+    int i = 0;
+    for (i=0; i<CHANNEL_NUM; i++) {
+        if (channel_ids[i] == 0) {
+            channel_ids[i] = id;
+            obj->ch = i;
+            found_free_channel = 1;
+            break;
+        }
+    }
+    if (!found_free_channel) return -1;
+    
+    /* Enable AHB clock to the GPIO domain. */
+    LPC_SYSCON->SYSAHBCLKCTRL |= (1<<6);
+    
+    /* Enable AHB clock to the FlexInt, GroupedInt domain. */
+    LPC_SYSCON->SYSAHBCLKCTRL |= ((1<<19) | (1<<23) | (1<<24));
+    
+    /* To select a pin for any of the eight pin interrupts, write the pin number
+     * as 0 to 23 for pins PIO0_0 to PIO0_23 and 24 to 55.
+     * @see: mbed_capi/PinNames.h
+     */
+    LPC_SYSCON->PINTSEL[obj->ch] = (pin >> 5) ? (pin - 8) : (pin);
+    
+    // Interrupt Wake-Up Enable
+    LPC_SYSCON->STARTERP0 |= 1 << obj->ch;
+    
+    void (*channels_irq)(void) = NULL;
+    switch (obj->ch) {
+        case 0: channels_irq = &gpio_irq0; break;
+        case 1: channels_irq = &gpio_irq1; break;
+        case 2: channels_irq = &gpio_irq2; break;
+        case 3: channels_irq = &gpio_irq3; break;
+        case 4: channels_irq = &gpio_irq4; break;
+        case 5: channels_irq = &gpio_irq5; break;
+        case 6: channels_irq = &gpio_irq6; break;
+        case 7: channels_irq = &gpio_irq7; break;
+    }
+    NVIC_SetVector((IRQn_Type)(PININT_IRQ + obj->ch), (uint32_t)channels_irq);
+    NVIC_EnableIRQ((IRQn_Type)(PININT_IRQ + obj->ch));
+    
+    return 0;
+}
+
+void gpio_irq_free(gpio_irq_t *obj) {
+    channel_ids[obj->ch] = 0;
+    LPC_SYSCON->STARTERP0 &= ~(1 << obj->ch);
+}
+
+void gpio_irq_set(gpio_irq_t *obj, gpio_irq_event event, uint32_t enable) {
+    unsigned int ch_bit = (1 << obj->ch);
+    
+    // Clear interrupt
+    if (!(LPC_GPIO_X->ISEL & ch_bit))
+        LPC_GPIO_X->IST = ch_bit;
+    
+    // Edge trigger
+    LPC_GPIO_X->ISEL &= ~ch_bit;
+    if (event == IRQ_RISE) {
+        if (enable) {
+            LPC_GPIO_X->IENR |= ch_bit;
+        } else {
+            LPC_GPIO_X->IENR &= ~ch_bit;
+        }
+    } else {
+        if (enable) {
+            LPC_GPIO_X->IENF |= ch_bit;
+        } else {
+            LPC_GPIO_X->IENF &= ~ch_bit;
+        }
+    }
+}
+
+void gpio_irq_enable(gpio_irq_t *obj) {
+    NVIC_EnableIRQ((IRQn_Type)(PININT_IRQ + obj->ch));
+}
+
+void gpio_irq_disable(gpio_irq_t *obj) {
+    NVIC_DisableIRQ((IRQn_Type)(PININT_IRQ + obj->ch));
+}