gptimers-example.c
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/*
* Simple gptimers example
* http://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gptimers
*
* Copyright 2007-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/interrupt.h>
#include <linux/module.h>
#include <asm/gptimers.h>
#include <asm/portmux.h>
/* ... random driver includes ... */
#define DRIVER_NAME "gptimer_example"
#ifdef IRQ_TIMER5
#define SAMPLE_IRQ_TIMER IRQ_TIMER5
#else
#define SAMPLE_IRQ_TIMER IRQ_TIMER2
#endif
struct gptimer_data {
uint32_t period, width;
};
static struct gptimer_data data;
/* ... random driver state ... */
static irqreturn_t gptimer_example_irq(int irq, void *dev_id)
{
struct gptimer_data *data = dev_id;
/* make sure it was our timer which caused the interrupt */
if (!get_gptimer_intr(TIMER5_id))
return IRQ_NONE;
/* read the width/period values that were captured for the waveform */
data->width = get_gptimer_pwidth(TIMER5_id);
data->period = get_gptimer_period(TIMER5_id);
/* acknowledge the interrupt */
clear_gptimer_intr(TIMER5_id);
/* tell the upper layers we took care of things */
return IRQ_HANDLED;
}
/* ... random driver code ... */
static int __init gptimer_example_init(void)
{
int ret;
/* grab the peripheral pins */
ret = peripheral_request(P_TMR5, DRIVER_NAME);
if (ret) {
printk(KERN_NOTICE DRIVER_NAME ": peripheral request failed\n");
return ret;
}
/* grab the IRQ for the timer */
ret = request_irq(SAMPLE_IRQ_TIMER, gptimer_example_irq,
IRQF_SHARED, DRIVER_NAME, &data);
if (ret) {
printk(KERN_NOTICE DRIVER_NAME ": IRQ request failed\n");
peripheral_free(P_TMR5);
return ret;
}
/* setup the timer and enable it */
set_gptimer_config(TIMER5_id,
WDTH_CAP | PULSE_HI | PERIOD_CNT | IRQ_ENA);
enable_gptimers(TIMER5bit);
return 0;
}
module_init(gptimer_example_init);
static void __exit gptimer_example_exit(void)
{
disable_gptimers(TIMER5bit);
free_irq(SAMPLE_IRQ_TIMER, &data);
peripheral_free(P_TMR5);
}
module_exit(gptimer_example_exit);
MODULE_LICENSE("BSD");