Diff: vendor/Freescale/KL25Z/hal/us_ticker.c

Revision:

13:0645d8841f51

Parent:

12:5fa2273de5db

Child:

14:096882eb0961

--- a/vendor/Freescale/KL25Z/hal/us_ticker.c	Wed Jul 24 11:11:21 2013 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,146 +0,0 @@
-/* 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 "us_ticker_api.h"
-#include "PeripheralNames.h"
-
-static void pit_init(void);
-static void lptmr_init(void);
-
-static int us_ticker_inited = 0;
-
-void us_ticker_init(void) {
-    if (us_ticker_inited) return;
-    us_ticker_inited = 1;
-    
-    pit_init();
-    lptmr_init();
-}
-
-/******************************************************************************
- * Timer for us timing.
- ******************************************************************************/
-static void pit_init(void) {
-    SIM->SCGC6 |= SIM_SCGC6_PIT_MASK;   // Clock PIT
-    PIT->MCR = 0;                       // Enable PIT
-    
-    // Channel 1
-    PIT->CHANNEL[1].LDVAL = 0xFFFFFFFF;
-    PIT->CHANNEL[1].TCTRL = PIT_TCTRL_CHN_MASK;    // Chain to timer 0, disable Interrupts
-    PIT->CHANNEL[1].TCTRL |= PIT_TCTRL_TEN_MASK;   // Start timer 1
-    
-    // Use channel 0 as a prescaler for channel 1
-    PIT->CHANNEL[0].LDVAL = 23;
-    PIT->CHANNEL[0].TCTRL = PIT_TCTRL_TEN_MASK;    // Start timer 0, disable interrupts
-}
-
-uint32_t us_ticker_read() {
-    if (!us_ticker_inited)
-        us_ticker_init();
-    
-    // The PIT is a countdown timer
-    return ~(PIT->CHANNEL[1].CVAL);
-}
-
-/******************************************************************************
- * Timer Event
- * 
- * It schedules interrupts at given (32bit)us interval of time.
- * It is implemented used the 16bit Low Power Timer that remains powered in all
- * power modes.
- ******************************************************************************/
-static void lptmr_isr(void);
-
-static void lptmr_init(void) {
-    /* Clock the timer */
-    SIM->SCGC5 |= SIM_SCGC5_LPTMR_MASK;
-    
-    /* Reset */
-    LPTMR0->CSR = 0;
-    
-    /* Set interrupt handler */
-    NVIC_SetVector(LPTimer_IRQn, (uint32_t)lptmr_isr);
-    NVIC_EnableIRQ(LPTimer_IRQn);
-    
-    /* Clock at (1)MHz -> (1)tick/us */
-    LPTMR0->PSR = LPTMR_PSR_PCS(3);       // OSCERCLK -> 8MHz
-    LPTMR0->PSR |= LPTMR_PSR_PRESCALE(2); // divide by 8
-}
-
-void us_ticker_disable_interrupt(void) {
-    LPTMR0->CSR &= ~LPTMR_CSR_TIE_MASK;
-}
-
-void us_ticker_clear_interrupt(void) {
-    // we already clear interrupt in lptmr_isr
-}
-
-static uint32_t us_ticker_int_counter = 0;
-static uint16_t us_ticker_int_remainder = 0;
-
-static void lptmr_set(unsigned short count) {
-    /* Reset */
-    LPTMR0->CSR = 0;
-    
-    /* Set the compare register */
-    LPTMR0->CMR = count;
-    
-    /* Enable interrupt */
-    LPTMR0->CSR |= LPTMR_CSR_TIE_MASK;
-    
-    /* Start the timer */
-    LPTMR0->CSR |= LPTMR_CSR_TEN_MASK;
-}
-
-static void lptmr_isr(void) {
-    // write 1 to TCF to clear the LPT timer compare flag
-    LPTMR0->CSR |= LPTMR_CSR_TCF_MASK;
-    
-    if (us_ticker_int_counter > 0) {
-        lptmr_set(0xFFFF);
-        us_ticker_int_counter--;
-    
-    } else {
-        if (us_ticker_int_remainder > 0) {
-            lptmr_set(us_ticker_int_remainder);
-            us_ticker_int_remainder = 0;
-        
-        } else {
-            // This function is going to disable the interrupts if there are
-            // no other events in the queue
-            us_ticker_irq_handler();
-        }
-    }
-}
-
-void us_ticker_set_interrupt(unsigned int timestamp) {
-    int delta = (int)(timestamp - us_ticker_read());
-    if (delta <= 0) {
-        // This event was in the past:
-        us_ticker_irq_handler();
-        return;
-    }
-    
-    us_ticker_int_counter   = (uint32_t)(delta >> 16);
-    us_ticker_int_remainder = (uint16_t)(0xFFFF & delta);
-    if (us_ticker_int_counter > 0) {
-        lptmr_set(0xFFFF);
-        us_ticker_int_counter--;
-    } else {
-        lptmr_set(us_ticker_int_remainder);
-        us_ticker_int_remainder = 0;
-    }
-}