diff options
author | Jonathan Cameron <jic23@cam.ac.uk> | 2009-08-18 13:06:30 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-09-15 15:02:25 -0400 |
commit | 7f3a1fb998e11a45d14556cc17f72d4f8aa89732 (patch) | |
tree | 7dbaa9c7e716a62cf0ea0ab8fe5a3d020d4c6e44 | |
parent | 0a1231dfea57516fb6cf107afdfb625a11a1cc5e (diff) |
Staging: IIO: Periodic timer based trigger
The original posting of this driver led to a discussion in
which it was commented that a better system was needed
for dealing with the many possible periodic interrupt
sources available on some SoCs. Unfortunately that is
a big task and as far as I know, no-one has taken it
on as yet. So in the meantime this driver is still
in here.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/staging/iio/Kconfig | 3 | ||||
-rw-r--r-- | drivers/staging/iio/Makefile | 4 | ||||
-rw-r--r-- | drivers/staging/iio/trigger/Kconfig | 15 | ||||
-rw-r--r-- | drivers/staging/iio/trigger/Makefile | 5 | ||||
-rw-r--r-- | drivers/staging/iio/trigger/iio-trig-periodic-rtc.c | 228 |
5 files changed, 254 insertions, 1 deletions
diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig index 869433f541c..beb99a547f0 100644 --- a/drivers/staging/iio/Kconfig +++ b/drivers/staging/iio/Kconfig | |||
@@ -37,8 +37,11 @@ config IIO_TRIGGER | |||
37 | ring buffers. The triggers are effectively a 'capture | 37 | ring buffers. The triggers are effectively a 'capture |
38 | data now' interrupt. | 38 | data now' interrupt. |
39 | 39 | ||
40 | |||
40 | source "drivers/staging/iio/accel/Kconfig" | 41 | source "drivers/staging/iio/accel/Kconfig" |
41 | source "drivers/staging/iio/adc/Kconfig" | 42 | source "drivers/staging/iio/adc/Kconfig" |
42 | source "drivers/staging/iio/light/Kconfig" | 43 | source "drivers/staging/iio/light/Kconfig" |
43 | 44 | ||
45 | source "drivers/staging/iio/trigger/Kconfig" | ||
46 | |||
44 | endif # IIO | 47 | endif # IIO |
diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile index dea4536ff82..7ec021810a7 100644 --- a/drivers/staging/iio/Makefile +++ b/drivers/staging/iio/Makefile | |||
@@ -11,4 +11,6 @@ obj-$(CONFIG_IIO_SW_RING) += ring_sw.o | |||
11 | 11 | ||
12 | obj-y += accel/ | 12 | obj-y += accel/ |
13 | obj-y += adc/ | 13 | obj-y += adc/ |
14 | obj-y += light/ \ No newline at end of file | 14 | obj-y += light/ |
15 | |||
16 | obj-y += trigger/ \ No newline at end of file | ||
diff --git a/drivers/staging/iio/trigger/Kconfig b/drivers/staging/iio/trigger/Kconfig new file mode 100644 index 00000000000..05ed139e153 --- /dev/null +++ b/drivers/staging/iio/trigger/Kconfig | |||
@@ -0,0 +1,15 @@ | |||
1 | # | ||
2 | # Industrial I/O standalone triggers | ||
3 | # | ||
4 | comment "Triggers - standalone" | ||
5 | |||
6 | if IIO_TRIGGER | ||
7 | |||
8 | config IIO_PERIODIC_RTC_TRIGGER | ||
9 | tristate "Periodic RTC triggers" | ||
10 | depends on RTC_CLASS | ||
11 | help | ||
12 | Provides support for using periodic capable real time | ||
13 | clocks as IIO triggers. | ||
14 | |||
15 | endif # IIO_TRIGGER | ||
diff --git a/drivers/staging/iio/trigger/Makefile b/drivers/staging/iio/trigger/Makefile new file mode 100644 index 00000000000..4ae55b9abae --- /dev/null +++ b/drivers/staging/iio/trigger/Makefile | |||
@@ -0,0 +1,5 @@ | |||
1 | # | ||
2 | # Makefile for triggers not associated with iio-devices | ||
3 | # | ||
4 | obj-$(CONFIG_IIO_PERIODIC_RTC_TRIGGER) += iio-trig-periodic-rtc.o | ||
5 | |||
diff --git a/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c b/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c new file mode 100644 index 00000000000..28c1d2d4a42 --- /dev/null +++ b/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c | |||
@@ -0,0 +1,228 @@ | |||
1 | /* The industrial I/O periodic RTC trigger driver | ||
2 | * | ||
3 | * Copyright (c) 2008 Jonathan Cameron | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or modify it | ||
6 | * under the terms of the GNU General Public License version 2 as published by | ||
7 | * the Free Software Foundation. | ||
8 | * | ||
9 | * This is a heavily rewritten version of the periodic timer system in | ||
10 | * earlier version of industrialio. It supplies the same functionality | ||
11 | * but via a trigger rather than a specific periodic timer system. | ||
12 | */ | ||
13 | |||
14 | #include <linux/platform_device.h> | ||
15 | #include <linux/kernel.h> | ||
16 | #include <linux/module.h> | ||
17 | #include <linux/rtc.h> | ||
18 | #include "../iio.h" | ||
19 | #include "../trigger.h" | ||
20 | |||
21 | LIST_HEAD(iio_prtc_trigger_list); | ||
22 | DEFINE_MUTEX(iio_prtc_trigger_list_lock); | ||
23 | |||
24 | struct iio_prtc_trigger_info { | ||
25 | struct rtc_device *rtc; | ||
26 | int frequency; | ||
27 | char *name; | ||
28 | struct rtc_task task; | ||
29 | }; | ||
30 | |||
31 | static int iio_trig_periodic_rtc_set_state(struct iio_trigger *trig, bool state) | ||
32 | { | ||
33 | struct iio_prtc_trigger_info *trig_info = trig->private_data; | ||
34 | if (trig_info->frequency == 0) | ||
35 | return -EINVAL; | ||
36 | printk(KERN_INFO "trigger frequency is %d\n", trig_info->frequency); | ||
37 | return rtc_irq_set_state(trig_info->rtc, &trig_info->task, state); | ||
38 | } | ||
39 | |||
40 | static ssize_t iio_trig_periodic_read_freq(struct device *dev, | ||
41 | struct device_attribute *attr, | ||
42 | char *buf) | ||
43 | { | ||
44 | struct iio_trigger *trig = dev_get_drvdata(dev); | ||
45 | struct iio_prtc_trigger_info *trig_info = trig->private_data; | ||
46 | return sprintf(buf, "%u\n", trig_info->frequency); | ||
47 | } | ||
48 | |||
49 | static ssize_t iio_trig_periodic_write_freq(struct device *dev, | ||
50 | struct device_attribute *attr, | ||
51 | const char *buf, | ||
52 | size_t len) | ||
53 | { | ||
54 | struct iio_trigger *trig = dev_get_drvdata(dev); | ||
55 | struct iio_prtc_trigger_info *trig_info = trig->private_data; | ||
56 | unsigned long val; | ||
57 | int ret; | ||
58 | |||
59 | ret = strict_strtoul(buf, 10, &val); | ||
60 | if (ret) | ||
61 | goto error_ret; | ||
62 | |||
63 | ret = rtc_irq_set_freq(trig_info->rtc, &trig_info->task, val); | ||
64 | if (ret) | ||
65 | goto error_ret; | ||
66 | |||
67 | trig_info->frequency = val; | ||
68 | |||
69 | return len; | ||
70 | |||
71 | error_ret: | ||
72 | return ret; | ||
73 | } | ||
74 | |||
75 | static ssize_t iio_trig_periodic_read_name(struct device *dev, | ||
76 | struct device_attribute *attr, | ||
77 | char *buf) | ||
78 | { | ||
79 | struct iio_trigger *trig = dev_get_drvdata(dev); | ||
80 | struct iio_prtc_trigger_info *trig_info = trig->private_data; | ||
81 | return sprintf(buf, "%s\n", trig_info->name); | ||
82 | } | ||
83 | |||
84 | DEVICE_ATTR(name, S_IRUGO, | ||
85 | iio_trig_periodic_read_name, | ||
86 | NULL); | ||
87 | DEVICE_ATTR(frequency, S_IRUGO | S_IWUSR, | ||
88 | iio_trig_periodic_read_freq, | ||
89 | iio_trig_periodic_write_freq); | ||
90 | |||
91 | static struct attribute *iio_trig_prtc_attrs[] = { | ||
92 | &dev_attr_frequency.attr, | ||
93 | &dev_attr_name.attr, | ||
94 | NULL, | ||
95 | }; | ||
96 | static const struct attribute_group iio_trig_prtc_attr_group = { | ||
97 | .attrs = iio_trig_prtc_attrs, | ||
98 | }; | ||
99 | |||
100 | static void iio_prtc_trigger_poll(void *private_data) | ||
101 | { | ||
102 | iio_trigger_poll(private_data); | ||
103 | } | ||
104 | |||
105 | static int iio_trig_periodic_rtc_probe(struct platform_device *dev) | ||
106 | { | ||
107 | char **pdata = dev->dev.platform_data; | ||
108 | struct iio_prtc_trigger_info *trig_info; | ||
109 | struct iio_trigger *trig, *trig2; | ||
110 | |||
111 | int i, ret; | ||
112 | |||
113 | for (i = 0;; i++) { | ||
114 | if (pdata[i] == NULL) | ||
115 | break; | ||
116 | trig = iio_allocate_trigger(); | ||
117 | if (!trig) { | ||
118 | ret = -ENOMEM; | ||
119 | goto error_free_completed_registrations; | ||
120 | } | ||
121 | list_add(&trig->alloc_list, &iio_prtc_trigger_list); | ||
122 | |||
123 | trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL); | ||
124 | if (!trig_info) { | ||
125 | ret = -ENOMEM; | ||
126 | goto error_put_trigger_and_remove_from_list; | ||
127 | } | ||
128 | trig->private_data = trig_info; | ||
129 | trig->owner = THIS_MODULE; | ||
130 | trig->set_trigger_state = &iio_trig_periodic_rtc_set_state; | ||
131 | trig->name = kmalloc(IIO_TRIGGER_NAME_LENGTH, GFP_KERNEL); | ||
132 | if (trig->name == NULL) { | ||
133 | ret = -ENOMEM; | ||
134 | goto error_free_trig_info; | ||
135 | } | ||
136 | snprintf((char *)trig->name, | ||
137 | IIO_TRIGGER_NAME_LENGTH, | ||
138 | "periodic%s", | ||
139 | pdata[i]); | ||
140 | trig_info->name = (char *)trig->name; | ||
141 | /* RTC access */ | ||
142 | trig_info->rtc | ||
143 | = rtc_class_open(pdata[i]); | ||
144 | if (trig_info->rtc == NULL) { | ||
145 | ret = -EINVAL; | ||
146 | goto error_free_name; | ||
147 | } | ||
148 | trig_info->task.func = iio_prtc_trigger_poll; | ||
149 | trig_info->task.private_data = trig; | ||
150 | ret = rtc_irq_register(trig_info->rtc, &trig_info->task); | ||
151 | if (ret) | ||
152 | goto error_close_rtc; | ||
153 | trig->control_attrs = &iio_trig_prtc_attr_group; | ||
154 | ret = iio_trigger_register(trig); | ||
155 | if (ret) | ||
156 | goto error_unregister_rtc_irq; | ||
157 | } | ||
158 | return 0; | ||
159 | error_unregister_rtc_irq: | ||
160 | rtc_irq_unregister(trig_info->rtc, &trig_info->task); | ||
161 | error_close_rtc: | ||
162 | rtc_class_close(trig_info->rtc); | ||
163 | error_free_name: | ||
164 | kfree(trig->name); | ||
165 | error_free_trig_info: | ||
166 | kfree(trig_info); | ||
167 | error_put_trigger_and_remove_from_list: | ||
168 | list_del(&trig->alloc_list); | ||
169 | iio_put_trigger(trig); | ||
170 | error_free_completed_registrations: | ||
171 | list_for_each_entry_safe(trig, | ||
172 | trig2, | ||
173 | &iio_prtc_trigger_list, | ||
174 | alloc_list) { | ||
175 | trig_info = trig->private_data; | ||
176 | rtc_irq_unregister(trig_info->rtc, &trig_info->task); | ||
177 | rtc_class_close(trig_info->rtc); | ||
178 | kfree(trig->name); | ||
179 | kfree(trig_info); | ||
180 | iio_trigger_unregister(trig); | ||
181 | } | ||
182 | return ret; | ||
183 | } | ||
184 | |||
185 | static int iio_trig_periodic_rtc_remove(struct platform_device *dev) | ||
186 | { | ||
187 | struct iio_trigger *trig, *trig2; | ||
188 | struct iio_prtc_trigger_info *trig_info; | ||
189 | mutex_lock(&iio_prtc_trigger_list_lock); | ||
190 | list_for_each_entry_safe(trig, | ||
191 | trig2, | ||
192 | &iio_prtc_trigger_list, | ||
193 | alloc_list) { | ||
194 | trig_info = trig->private_data; | ||
195 | rtc_irq_unregister(trig_info->rtc, &trig_info->task); | ||
196 | rtc_class_close(trig_info->rtc); | ||
197 | kfree(trig->name); | ||
198 | kfree(trig_info); | ||
199 | iio_trigger_unregister(trig); | ||
200 | } | ||
201 | mutex_unlock(&iio_prtc_trigger_list_lock); | ||
202 | return 0; | ||
203 | } | ||
204 | |||
205 | static struct platform_driver iio_trig_periodic_rtc_driver = { | ||
206 | .probe = iio_trig_periodic_rtc_probe, | ||
207 | .remove = iio_trig_periodic_rtc_remove, | ||
208 | .driver = { | ||
209 | .name = "iio_prtc_trigger", | ||
210 | .owner = THIS_MODULE, | ||
211 | }, | ||
212 | }; | ||
213 | |||
214 | static int __init iio_trig_periodic_rtc_init(void) | ||
215 | { | ||
216 | return platform_driver_register(&iio_trig_periodic_rtc_driver); | ||
217 | } | ||
218 | |||
219 | static void __exit iio_trig_periodic_rtc_exit(void) | ||
220 | { | ||
221 | return platform_driver_unregister(&iio_trig_periodic_rtc_driver); | ||
222 | } | ||
223 | |||
224 | module_init(iio_trig_periodic_rtc_init); | ||
225 | module_exit(iio_trig_periodic_rtc_exit); | ||
226 | MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>"); | ||
227 | MODULE_DESCRIPTION("Periodic realtime clock trigger for the iio subsystem"); | ||
228 | MODULE_LICENSE("GPL v2"); | ||