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14#include <linux/platform_device.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/slab.h>
18#include <linux/rtc.h>
19#include "../iio.h"
20#include "../trigger.h"
21
22static LIST_HEAD(iio_prtc_trigger_list);
23static DEFINE_MUTEX(iio_prtc_trigger_list_lock);
24
25struct iio_prtc_trigger_info {
26 struct rtc_device *rtc;
27 int frequency;
28 struct rtc_task task;
29};
30
31static 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
40static 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
49static 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
71error_ret:
72 return ret;
73}
74
75static IIO_TRIGGER_NAME_ATTR;
76static DEVICE_ATTR(frequency, S_IRUGO | S_IWUSR,
77 iio_trig_periodic_read_freq,
78 iio_trig_periodic_write_freq);
79
80static struct attribute *iio_trig_prtc_attrs[] = {
81 &dev_attr_frequency.attr,
82 &dev_attr_name.attr,
83 NULL,
84};
85static const struct attribute_group iio_trig_prtc_attr_group = {
86 .attrs = iio_trig_prtc_attrs,
87};
88
89static void iio_prtc_trigger_poll(void *private_data)
90{
91
92 iio_trigger_poll(private_data, 0);
93}
94
95static int iio_trig_periodic_rtc_probe(struct platform_device *dev)
96{
97 char **pdata = dev->dev.platform_data;
98 struct iio_prtc_trigger_info *trig_info;
99 struct iio_trigger *trig, *trig2;
100
101 int i, ret;
102
103 for (i = 0;; i++) {
104 if (pdata[i] == NULL)
105 break;
106 trig = iio_allocate_trigger();
107 if (!trig) {
108 ret = -ENOMEM;
109 goto error_free_completed_registrations;
110 }
111 list_add(&trig->alloc_list, &iio_prtc_trigger_list);
112
113 trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
114 if (!trig_info) {
115 ret = -ENOMEM;
116 goto error_put_trigger_and_remove_from_list;
117 }
118 trig->private_data = trig_info;
119 trig->owner = THIS_MODULE;
120 trig->set_trigger_state = &iio_trig_periodic_rtc_set_state;
121 trig->name = kasprintf(GFP_KERNEL, "periodic%s", pdata[i]);
122 if (trig->name == NULL) {
123 ret = -ENOMEM;
124 goto error_free_trig_info;
125 }
126
127
128 trig_info->rtc
129 = rtc_class_open(pdata[i]);
130 if (trig_info->rtc == NULL) {
131 ret = -EINVAL;
132 goto error_free_name;
133 }
134 trig_info->task.func = iio_prtc_trigger_poll;
135 trig_info->task.private_data = trig;
136 ret = rtc_irq_register(trig_info->rtc, &trig_info->task);
137 if (ret)
138 goto error_close_rtc;
139 trig->control_attrs = &iio_trig_prtc_attr_group;
140 ret = iio_trigger_register(trig);
141 if (ret)
142 goto error_unregister_rtc_irq;
143 }
144 return 0;
145error_unregister_rtc_irq:
146 rtc_irq_unregister(trig_info->rtc, &trig_info->task);
147error_close_rtc:
148 rtc_class_close(trig_info->rtc);
149error_free_name:
150 kfree(trig->name);
151error_free_trig_info:
152 kfree(trig_info);
153error_put_trigger_and_remove_from_list:
154 list_del(&trig->alloc_list);
155 iio_put_trigger(trig);
156error_free_completed_registrations:
157 list_for_each_entry_safe(trig,
158 trig2,
159 &iio_prtc_trigger_list,
160 alloc_list) {
161 trig_info = trig->private_data;
162 rtc_irq_unregister(trig_info->rtc, &trig_info->task);
163 rtc_class_close(trig_info->rtc);
164 kfree(trig->name);
165 kfree(trig_info);
166 iio_trigger_unregister(trig);
167 }
168 return ret;
169}
170
171static int iio_trig_periodic_rtc_remove(struct platform_device *dev)
172{
173 struct iio_trigger *trig, *trig2;
174 struct iio_prtc_trigger_info *trig_info;
175 mutex_lock(&iio_prtc_trigger_list_lock);
176 list_for_each_entry_safe(trig,
177 trig2,
178 &iio_prtc_trigger_list,
179 alloc_list) {
180 trig_info = trig->private_data;
181 rtc_irq_unregister(trig_info->rtc, &trig_info->task);
182 rtc_class_close(trig_info->rtc);
183 kfree(trig->name);
184 kfree(trig_info);
185 iio_trigger_unregister(trig);
186 }
187 mutex_unlock(&iio_prtc_trigger_list_lock);
188 return 0;
189}
190
191static struct platform_driver iio_trig_periodic_rtc_driver = {
192 .probe = iio_trig_periodic_rtc_probe,
193 .remove = iio_trig_periodic_rtc_remove,
194 .driver = {
195 .name = "iio_prtc_trigger",
196 .owner = THIS_MODULE,
197 },
198};
199
200static int __init iio_trig_periodic_rtc_init(void)
201{
202 return platform_driver_register(&iio_trig_periodic_rtc_driver);
203}
204
205static void __exit iio_trig_periodic_rtc_exit(void)
206{
207 return platform_driver_unregister(&iio_trig_periodic_rtc_driver);
208}
209
210module_init(iio_trig_periodic_rtc_init);
211module_exit(iio_trig_periodic_rtc_exit);
212MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
213MODULE_DESCRIPTION("Periodic realtime clock trigger for the iio subsystem");
214MODULE_LICENSE("GPL v2");
215
