Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * The industrial I/O periodic hrtimer trigger driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) Intuitive Aerial AB
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * Written by Marten Svanfeldt, marten@intuitiveaerial.com
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  * Copyright (C) 2012, Analog Devices Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  *	Author: Lars-Peter Clausen <lars@metafoo.de>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  * Copyright (C) 2015, Intel Corporation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/hrtimer.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/iio/iio.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/iio/trigger.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/iio/sw_trigger.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) /* default sampling frequency - 100Hz */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #define HRTIMER_DEFAULT_SAMPLING_FREQUENCY 100
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) struct iio_hrtimer_info {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	struct iio_sw_trigger swt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	struct hrtimer timer;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	unsigned long sampling_frequency;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	ktime_t period;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) static const struct config_item_type iio_hrtimer_type = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	.ct_owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) ssize_t iio_hrtimer_show_sampling_frequency(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 					    struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 					    char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	struct iio_trigger *trig = to_iio_trigger(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	struct iio_hrtimer_info *info = iio_trigger_get_drvdata(trig);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	return snprintf(buf, PAGE_SIZE, "%lu\n", info->sampling_frequency);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) static
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) ssize_t iio_hrtimer_store_sampling_frequency(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 					     struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 					     const char *buf, size_t len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	struct iio_trigger *trig = to_iio_trigger(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	struct iio_hrtimer_info *info = iio_trigger_get_drvdata(trig);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	unsigned long val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	ret = kstrtoul(buf, 10, &val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 		return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	if (!val || val > NSEC_PER_SEC)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	info->sampling_frequency = val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	info->period = NSEC_PER_SEC / val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) static DEVICE_ATTR(sampling_frequency, S_IRUGO | S_IWUSR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		   iio_hrtimer_show_sampling_frequency,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 		   iio_hrtimer_store_sampling_frequency);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) static struct attribute *iio_hrtimer_attrs[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	&dev_attr_sampling_frequency.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) static const struct attribute_group iio_hrtimer_attr_group = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	.attrs = iio_hrtimer_attrs,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) static const struct attribute_group *iio_hrtimer_attr_groups[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	&iio_hrtimer_attr_group,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) static enum hrtimer_restart iio_hrtimer_trig_handler(struct hrtimer *timer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	struct iio_hrtimer_info *info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	info = container_of(timer, struct iio_hrtimer_info, timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	hrtimer_forward_now(timer, info->period);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	iio_trigger_poll(info->swt.trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	return HRTIMER_RESTART;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) static int iio_trig_hrtimer_set_state(struct iio_trigger *trig, bool state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	struct iio_hrtimer_info *trig_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	trig_info = iio_trigger_get_drvdata(trig);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	if (state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		hrtimer_start(&trig_info->timer, trig_info->period,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 			      HRTIMER_MODE_REL_HARD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		hrtimer_cancel(&trig_info->timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) static const struct iio_trigger_ops iio_hrtimer_trigger_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	.set_trigger_state = iio_trig_hrtimer_set_state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) static struct iio_sw_trigger *iio_trig_hrtimer_probe(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	struct iio_hrtimer_info *trig_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	if (!trig_info)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 		return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	trig_info->swt.trigger = iio_trigger_alloc("%s", name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	if (!trig_info->swt.trigger) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 		goto err_free_trig_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	iio_trigger_set_drvdata(trig_info->swt.trigger, trig_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	trig_info->swt.trigger->ops = &iio_hrtimer_trigger_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	trig_info->swt.trigger->dev.groups = iio_hrtimer_attr_groups;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	hrtimer_init(&trig_info->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	trig_info->timer.function = iio_hrtimer_trig_handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	trig_info->sampling_frequency = HRTIMER_DEFAULT_SAMPLING_FREQUENCY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	trig_info->period = NSEC_PER_SEC / trig_info->sampling_frequency;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	ret = iio_trigger_register(trig_info->swt.trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		goto err_free_trigger;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	iio_swt_group_init_type_name(&trig_info->swt, name, &iio_hrtimer_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	return &trig_info->swt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) err_free_trigger:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	iio_trigger_free(trig_info->swt.trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) err_free_trig_info:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	kfree(trig_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	return ERR_PTR(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) static int iio_trig_hrtimer_remove(struct iio_sw_trigger *swt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	struct iio_hrtimer_info *trig_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	trig_info = iio_trigger_get_drvdata(swt->trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	iio_trigger_unregister(swt->trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	/* cancel the timer after unreg to make sure no one rearms it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	hrtimer_cancel(&trig_info->timer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	iio_trigger_free(swt->trigger);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	kfree(trig_info);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) static const struct iio_sw_trigger_ops iio_trig_hrtimer_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	.probe		= iio_trig_hrtimer_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	.remove		= iio_trig_hrtimer_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) static struct iio_sw_trigger_type iio_trig_hrtimer = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	.name = "hrtimer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	.owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	.ops = &iio_trig_hrtimer_ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) module_iio_sw_trigger_driver(iio_trig_hrtimer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) MODULE_AUTHOR("Marten Svanfeldt <marten@intuitiveaerial.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) MODULE_DESCRIPTION("Periodic hrtimer trigger for the IIO subsystem");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) MODULE_LICENSE("GPL v2");