Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 488 insertions, 0 deletions

diff --git a/drivers/iio/proximity/as3935.c b/drivers/iio/proximity/as3935.c
new file mode 100644
index 000000000..98330e26a
--- /dev/null
+++ b/drivers/iio/proximity/as3935.c
@@ -0,0 +1,488 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * as3935.c - Support for AS3935 Franklin lightning sensor
+ *
+ * Copyright (C) 2014, 2017-2018
+ * Author: Matt Ranostay <matt.ranostay@konsulko.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/spi/spi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define AS3935_AFE_GAIN		0x00
+#define AS3935_AFE_MASK		0x3F
+#define AS3935_AFE_GAIN_MAX	0x1F
+#define AS3935_AFE_PWR_BIT	BIT(0)
+
+#define AS3935_NFLWDTH		0x01
+#define AS3935_NFLWDTH_MASK	0x7f
+
+#define AS3935_INT		0x03
+#define AS3935_INT_MASK		0x0f
+#define AS3935_DISTURB_INT	BIT(2)
+#define AS3935_EVENT_INT	BIT(3)
+#define AS3935_NOISE_INT	BIT(0)
+
+#define AS3935_DATA		0x07
+#define AS3935_DATA_MASK	0x3F
+
+#define AS3935_TUNE_CAP		0x08
+#define AS3935_DEFAULTS		0x3C
+#define AS3935_CALIBRATE	0x3D
+
+#define AS3935_READ_DATA	BIT(14)
+#define AS3935_ADDRESS(x)	((x) << 8)
+
+#define MAX_PF_CAP		120
+#define TUNE_CAP_DIV		8
+
+struct as3935_state {
+	struct spi_device *spi;
+	struct iio_trigger *trig;
+	struct mutex lock;
+	struct delayed_work work;
+
+	unsigned long noise_tripped;
+	u32 tune_cap;
+	u32 nflwdth_reg;
+	/* Ensure timestamp is naturally aligned */
+	struct {
+		u8 chan;
+		s64 timestamp __aligned(8);
+	} scan;
+	u8 buf[2] ____cacheline_aligned;
+};
+
+static const struct iio_chan_spec as3935_channels[] = {
+	{
+		.type           = IIO_PROXIMITY,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) |
+			BIT(IIO_CHAN_INFO_PROCESSED) |
+			BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index     = 0,
+		.scan_type = {
+			.sign           = 'u',
+			.realbits       = 6,
+			.storagebits    = 8,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+static int as3935_read(struct as3935_state *st, unsigned int reg, int *val)
+{
+	u8 cmd;
+	int ret;
+
+	cmd = (AS3935_READ_DATA | AS3935_ADDRESS(reg)) >> 8;
+	ret = spi_w8r8(st->spi, cmd);
+	if (ret < 0)
+		return ret;
+	*val = ret;
+
+	return 0;
+}
+
+static int as3935_write(struct as3935_state *st,
+				unsigned int reg,
+				unsigned int val)
+{
+	u8 *buf = st->buf;
+
+	buf[0] = AS3935_ADDRESS(reg) >> 8;
+	buf[1] = val;
+
+	return spi_write(st->spi, buf, 2);
+}
+
+static ssize_t as3935_sensor_sensitivity_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct as3935_state *st = iio_priv(dev_to_iio_dev(dev));
+	int val, ret;
+
+	ret = as3935_read(st, AS3935_AFE_GAIN, &val);
+	if (ret)
+		return ret;
+	val = (val & AS3935_AFE_MASK) >> 1;
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t as3935_sensor_sensitivity_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t len)
+{
+	struct as3935_state *st = iio_priv(dev_to_iio_dev(dev));
+	unsigned long val;
+	int ret;
+
+	ret = kstrtoul((const char *) buf, 10, &val);
+	if (ret)
+		return -EINVAL;
+
+	if (val > AS3935_AFE_GAIN_MAX)
+		return -EINVAL;
+
+	as3935_write(st, AS3935_AFE_GAIN, val << 1);
+
+	return len;
+}
+
+static ssize_t as3935_noise_level_tripped_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct as3935_state *st = iio_priv(dev_to_iio_dev(dev));
+	int ret;
+
+	mutex_lock(&st->lock);
+	ret = sprintf(buf, "%d\n", !time_after(jiffies, st->noise_tripped + HZ));
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+
+static IIO_DEVICE_ATTR(sensor_sensitivity, S_IRUGO | S_IWUSR,
+	as3935_sensor_sensitivity_show, as3935_sensor_sensitivity_store, 0);
+
+static IIO_DEVICE_ATTR(noise_level_tripped, S_IRUGO,
+	as3935_noise_level_tripped_show, NULL, 0);
+
+static struct attribute *as3935_attributes[] = {
+	&iio_dev_attr_sensor_sensitivity.dev_attr.attr,
+	&iio_dev_attr_noise_level_tripped.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group as3935_attribute_group = {
+	.attrs = as3935_attributes,
+};
+
+static int as3935_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct as3935_state *st = iio_priv(indio_dev);
+	int ret;
+
+
+	switch (m) {
+	case IIO_CHAN_INFO_PROCESSED:
+	case IIO_CHAN_INFO_RAW:
+		*val2 = 0;
+		ret = as3935_read(st, AS3935_DATA, val);
+		if (ret)
+			return ret;
+
+		/* storm out of range */
+		if (*val == AS3935_DATA_MASK)
+			return -EINVAL;
+
+		if (m == IIO_CHAN_INFO_RAW)
+			return IIO_VAL_INT;
+
+		if (m == IIO_CHAN_INFO_PROCESSED)
+			*val *= 1000;
+		break;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return IIO_VAL_INT;
+}
+
+static const struct iio_info as3935_info = {
+	.attrs = &as3935_attribute_group,
+	.read_raw = &as3935_read_raw,
+};
+
+static irqreturn_t as3935_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct as3935_state *st = iio_priv(indio_dev);
+	int val, ret;
+
+	ret = as3935_read(st, AS3935_DATA, &val);
+	if (ret)
+		goto err_read;
+
+	st->scan.chan = val & AS3935_DATA_MASK;
+	iio_push_to_buffers_with_timestamp(indio_dev, &st->scan,
+					   iio_get_time_ns(indio_dev));
+err_read:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_trigger_ops iio_interrupt_trigger_ops = {
+};
+
+static void as3935_event_work(struct work_struct *work)
+{
+	struct as3935_state *st;
+	int val;
+	int ret;
+
+	st = container_of(work, struct as3935_state, work.work);
+
+	ret = as3935_read(st, AS3935_INT, &val);
+	if (ret) {
+		dev_warn(&st->spi->dev, "read error\n");
+		return;
+	}
+
+	val &= AS3935_INT_MASK;
+
+	switch (val) {
+	case AS3935_EVENT_INT:
+		iio_trigger_poll_chained(st->trig);
+		break;
+	case AS3935_DISTURB_INT:
+	case AS3935_NOISE_INT:
+		mutex_lock(&st->lock);
+		st->noise_tripped = jiffies;
+		mutex_unlock(&st->lock);
+		dev_warn(&st->spi->dev, "noise level is too high\n");
+		break;
+	}
+}
+
+static irqreturn_t as3935_interrupt_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct as3935_state *st = iio_priv(indio_dev);
+
+	/*
+	 * Delay work for >2 milliseconds after an interrupt to allow
+	 * estimated distance to recalculated.
+	 */
+
+	schedule_delayed_work(&st->work, msecs_to_jiffies(3));
+
+	return IRQ_HANDLED;
+}
+
+static void calibrate_as3935(struct as3935_state *st)
+{
+	as3935_write(st, AS3935_DEFAULTS, 0x96);
+	as3935_write(st, AS3935_CALIBRATE, 0x96);
+	as3935_write(st, AS3935_TUNE_CAP,
+		BIT(5) | (st->tune_cap / TUNE_CAP_DIV));
+
+	mdelay(2);
+	as3935_write(st, AS3935_TUNE_CAP, (st->tune_cap / TUNE_CAP_DIV));
+	as3935_write(st, AS3935_NFLWDTH, st->nflwdth_reg);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int as3935_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct as3935_state *st = iio_priv(indio_dev);
+	int val, ret;
+
+	mutex_lock(&st->lock);
+	ret = as3935_read(st, AS3935_AFE_GAIN, &val);
+	if (ret)
+		goto err_suspend;
+	val |= AS3935_AFE_PWR_BIT;
+
+	ret = as3935_write(st, AS3935_AFE_GAIN, val);
+
+err_suspend:
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+
+static int as3935_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct as3935_state *st = iio_priv(indio_dev);
+	int val, ret;
+
+	mutex_lock(&st->lock);
+	ret = as3935_read(st, AS3935_AFE_GAIN, &val);
+	if (ret)
+		goto err_resume;
+	val &= ~AS3935_AFE_PWR_BIT;
+	ret = as3935_write(st, AS3935_AFE_GAIN, val);
+
+	calibrate_as3935(st);
+
+err_resume:
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(as3935_pm_ops, as3935_suspend, as3935_resume);
+#define AS3935_PM_OPS (&as3935_pm_ops)
+
+#else
+#define AS3935_PM_OPS NULL
+#endif
+
+static void as3935_stop_work(void *data)
+{
+	struct iio_dev *indio_dev = data;
+	struct as3935_state *st = iio_priv(indio_dev);
+
+	cancel_delayed_work_sync(&st->work);
+}
+
+static int as3935_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct iio_dev *indio_dev;
+	struct iio_trigger *trig;
+	struct as3935_state *st;
+	int ret;
+
+	/* Be sure lightning event interrupt is specified */
+	if (!spi->irq) {
+		dev_err(dev, "unable to get event interrupt\n");
+		return -EINVAL;
+	}
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->spi = spi;
+
+	spi_set_drvdata(spi, indio_dev);
+	mutex_init(&st->lock);
+
+	ret = device_property_read_u32(dev,
+			"ams,tuning-capacitor-pf", &st->tune_cap);
+	if (ret) {
+		st->tune_cap = 0;
+		dev_warn(dev, "no tuning-capacitor-pf set, defaulting to %d",
+			st->tune_cap);
+	}
+
+	if (st->tune_cap > MAX_PF_CAP) {
+		dev_err(dev, "wrong tuning-capacitor-pf setting of %d\n",
+			st->tune_cap);
+		return -EINVAL;
+	}
+
+	ret = device_property_read_u32(dev,
+			"ams,nflwdth", &st->nflwdth_reg);
+	if (!ret && st->nflwdth_reg > AS3935_NFLWDTH_MASK) {
+		dev_err(dev, "invalid nflwdth setting of %d\n",
+			st->nflwdth_reg);
+		return -EINVAL;
+	}
+
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->channels = as3935_channels;
+	indio_dev->num_channels = ARRAY_SIZE(as3935_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &as3935_info;
+
+	trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+				      indio_dev->name, indio_dev->id);
+
+	if (!trig)
+		return -ENOMEM;
+
+	st->trig = trig;
+	st->noise_tripped = jiffies - HZ;
+	trig->dev.parent = indio_dev->dev.parent;
+	iio_trigger_set_drvdata(trig, indio_dev);
+	trig->ops = &iio_interrupt_trigger_ops;
+
+	ret = devm_iio_trigger_register(dev, trig);
+	if (ret) {
+		dev_err(dev, "failed to register trigger\n");
+		return ret;
+	}
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
+					      iio_pollfunc_store_time,
+					      as3935_trigger_handler, NULL);
+
+	if (ret) {
+		dev_err(dev, "cannot setup iio trigger\n");
+		return ret;
+	}
+
+	calibrate_as3935(st);
+
+	INIT_DELAYED_WORK(&st->work, as3935_event_work);
+	ret = devm_add_action(dev, as3935_stop_work, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(dev, spi->irq,
+				&as3935_interrupt_handler,
+				IRQF_TRIGGER_RISING,
+				dev_name(dev),
+				indio_dev);
+
+	if (ret) {
+		dev_err(dev, "unable to request irq\n");
+		return ret;
+	}
+
+	ret = devm_iio_device_register(dev, indio_dev);
+	if (ret < 0) {
+		dev_err(dev, "unable to register device\n");
+		return ret;
+	}
+	return 0;
+}
+
+static const struct of_device_id as3935_of_match[] = {
+	{ .compatible = "ams,as3935", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, as3935_of_match);
+
+static const struct spi_device_id as3935_id[] = {
+	{"as3935", 0},
+	{},
+};
+MODULE_DEVICE_TABLE(spi, as3935_id);
+
+static struct spi_driver as3935_driver = {
+	.driver = {
+		.name	= "as3935",
+		.of_match_table = as3935_of_match,
+		.pm	= AS3935_PM_OPS,
+	},
+	.probe		= as3935_probe,
+	.id_table	= as3935_id,
+};
+module_spi_driver(as3935_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("AS3935 lightning sensor");
+MODULE_LICENSE("GPL");