tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Blackfin: add an example showing how to use the gptimers API
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
+89
+6
Documentation/blackfin/Makefile
+6
Documentation/blackfin/Makefile
+83
Documentation/blackfin/gptimers-example.c
+83
Documentation/blackfin/gptimers-example.c
···
1
+
/*
2
+
* Simple gptimers example
3
+
* http://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:drivers:gptimers
4
+
*
5
+
* Copyright 2007-2009 Analog Devices Inc.
6
+
*
7
+
* Licensed under the GPL-2 or later.
8
+
*/
9
+
10
+
#include <linux/interrupt.h>
11
+
#include <linux/module.h>
12
+
13
+
#include <asm/gptimers.h>
14
+
#include <asm/portmux.h>
15
+
16
+
/* ... random driver includes ... */
17
+
18
+
#define DRIVER_NAME "gptimer_example"
19
+
20
+
struct gptimer_data {
21
+
uint32_t period, width;
22
+
};
23
+
static struct gptimer_data data;
24
+
25
+
/* ... random driver state ... */
26
+
27
+
static irqreturn_t gptimer_example_irq(int irq, void *dev_id)
28
+
{
29
+
struct gptimer_data *data = dev_id;
30
+
31
+
/* make sure it was our timer which caused the interrupt */
32
+
if (!get_gptimer_intr(TIMER5_id))
33
+
return IRQ_NONE;
34
+
35
+
/* read the width/period values that were captured for the waveform */
36
+
data->width = get_gptimer_pwidth(TIMER5_id);
37
+
data->period = get_gptimer_period(TIMER5_id);
38
+
39
+
/* acknowledge the interrupt */
40
+
clear_gptimer_intr(TIMER5_id);
41
+
42
+
/* tell the upper layers we took care of things */
43
+
return IRQ_HANDLED;
44
+
}
45
+
46
+
/* ... random driver code ... */
47
+
48
+
static int __init gptimer_example_init(void)
49
+
{
50
+
int ret;
51
+
52
+
/* grab the peripheral pins */
53
+
ret = peripheral_request(P_TMR5, DRIVER_NAME);
54
+
if (ret) {
55
+
printk(KERN_NOTICE DRIVER_NAME ": peripheral request failed\n");
56
+
return ret;
57
+
}
58
+
59
+
/* grab the IRQ for the timer */
60
+
ret = request_irq(IRQ_TIMER5, gptimer_example_irq, IRQF_SHARED, DRIVER_NAME, &data);
61
+
if (ret) {
62
+
printk(KERN_NOTICE DRIVER_NAME ": IRQ request failed\n");
63
+
peripheral_free(P_TMR5);
64
+
return ret;
65
+
}
66
+
67
+
/* setup the timer and enable it */
68
+
set_gptimer_config(TIMER5_id, WDTH_CAP | PULSE_HI | PERIOD_CNT | IRQ_ENA);
69
+
enable_gptimers(TIMER5bit);
70
+
71
+
return 0;
72
+
}
73
+
module_init(gptimer_example_init);
74
+
75
+
static void __exit gptimer_example_exit(void)
76
+
{
77
+
disable_gptimers(TIMER5bit);
78
+
free_irq(IRQ_TIMER5, &data);
79
+
peripheral_free(P_TMR5);
80
+
}
81
+
module_exit(gptimer_example_exit);
82
+
83
+
MODULE_LICENSE("BSD");