[PATCH v8 0/2] AS3935 lightning sensor support

[PATCH v8 0/2] AS3935 lightning sensor support

[Matt Ranostay]

This series adds support for the AMS AS3935 lightning sensor that allows
reporting back estimated storm distance and strike events.

Changes from v7

* Added IIO_CHAN_INFO_PROCESSED to report back meter converted
* Storm out-of-range is reported as -EINVAL instead of mystery value 63000
* Fixed error unwinding order in as3935_probe()
* Renamed value gain_boot attribute to sensor_sensitivity

Changes from v6

* Revised binding documents to not use the term "interrupts mapping"
* Renamed tune-cap property to a more clear tuning-capacitor-pf

Changes from v5

* SPI write cache-aligned issues fixed
* Fixed mutex_unlock's being missed
* Reports distance in meters instead of kilometers (1km steps)
* tune_cap is now in picofarads and not a register value

Matt Ranostay (2):
  iio:as3935: Add DT binding docs for AS3935 driver
  iio: Add AS3935 lightning sensor support

 .../ABI/testing/sysfs-bus-iio-proximity-as3935     |  16 +
 .../devicetree/bindings/iio/proximity/as3935.txt   |  28 ++
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 drivers/iio/Kconfig                                |   1 +
 drivers/iio/Makefile                               |   1 +
 drivers/iio/proximity/Kconfig                      |  19 +
 drivers/iio/proximity/Makefile                     |   6 +
 drivers/iio/proximity/as3935.c                     | 456 +++++++++++++++++++++
 8 files changed, 528 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
 create mode 100644 Documentation/devicetree/bindings/iio/proximity/as3935.txt
 create mode 100644 drivers/iio/proximity/Kconfig
 create mode 100644 drivers/iio/proximity/Makefile
 create mode 100644 drivers/iio/proximity/as3935.c

-- 
1.8.3.2

[PATCH v8 1/2] iio:as3935: Add DT binding docs for AS3935 driver

[Matt Ranostay]

Document compatible string, required and optional DT properties for
AS3935 chipset driver.

Signed-off-by: Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 .../devicetree/bindings/iio/proximity/as3935.txt   | 28 ++++++++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.txt        |  1 +
 2 files changed, 29 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/proximity/as3935.txt

diff --git a/Documentation/devicetree/bindings/iio/proximity/as3935.txt b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
new file mode 100644
index 0000000..ae23dd8
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
@@ -0,0 +1,28 @@
+Austrian Microsystems AS3935 Franklin lightning sensor device driver
+
+Required properties:
+	- compatible: must be "ams,as3935"
+	- reg: SPI chip select number for the device
+	- spi-cpha: SPI Mode 1. Refer to spi/spi-bus.txt for generic SPI
+	slave node bindings.
+	- interrupt-parent : should be the phandle for the interrupt controller
+	- interrupts : the sole interrupt generated by the device
+
+	Refer to interrupt-controller/interrupts.txt for generic
+	interrupt client node bindings.
+
+Optional properties:
+	- ams,tuning-capacitor-pf: Calibration tuning capacitor stepping
+	  value 0 - 120pF. This will require using the calibration data from
+	  the manufacturer.
+
+Example:
+
+as3935@0 {
+	compatible = "ams,as3935";
+	reg = <0>;
+	spi-cpha;
+	interrupt-parent = <&gpio1>;
+	interrupts = <16 1>;
+	ams,tuning-capacitor-pf = <80>;
+};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 4685ec3..517831d 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -11,6 +11,7 @@ ak	Asahi Kasei Corp.
 allwinner	Allwinner Technology Co., Ltd.
 altr	Altera Corp.
 amcc	Applied Micro Circuits Corporation (APM, formally AMCC)
+ams	AMS AG
 amstaos	AMS-Taos Inc.
 apm	Applied Micro Circuits Corporation (APM)
 arm	ARM Ltd.
-- 
1.8.3.2

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Re: [PATCH v8 1/2] iio:as3935: Add DT binding docs for AS3935 driver

[Rob Herring]

On Wed, Mar 12, 2014 at 7:53 AM, Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Document compatible string, required and optional DT properties for
> AS3935 chipset driver.
>
> Signed-off-by: Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

> ---
>  .../devicetree/bindings/iio/proximity/as3935.txt   | 28 ++++++++++++++++++++++
>  .../devicetree/bindings/vendor-prefixes.txt        |  1 +
>  2 files changed, 29 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/proximity/as3935.txt
>
> diff --git a/Documentation/devicetree/bindings/iio/proximity/as3935.txt b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
> new file mode 100644
> index 0000000..ae23dd8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
> @@ -0,0 +1,28 @@
> +Austrian Microsystems AS3935 Franklin lightning sensor device driver
> +
> +Required properties:
> +       - compatible: must be "ams,as3935"
> +       - reg: SPI chip select number for the device
> +       - spi-cpha: SPI Mode 1. Refer to spi/spi-bus.txt for generic SPI
> +       slave node bindings.
> +       - interrupt-parent : should be the phandle for the interrupt controller
> +       - interrupts : the sole interrupt generated by the device
> +
> +       Refer to interrupt-controller/interrupts.txt for generic
> +       interrupt client node bindings.
> +
> +Optional properties:
> +       - ams,tuning-capacitor-pf: Calibration tuning capacitor stepping
> +         value 0 - 120pF. This will require using the calibration data from
> +         the manufacturer.
> +
> +Example:
> +
> +as3935@0 {
> +       compatible = "ams,as3935";
> +       reg = <0>;
> +       spi-cpha;
> +       interrupt-parent = <&gpio1>;
> +       interrupts = <16 1>;
> +       ams,tuning-capacitor-pf = <80>;
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index 4685ec3..517831d 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -11,6 +11,7 @@ ak    Asahi Kasei Corp.
>  allwinner      Allwinner Technology Co., Ltd.
>  altr   Altera Corp.
>  amcc   Applied Micro Circuits Corporation (APM, formally AMCC)
> +ams    AMS AG
>  amstaos        AMS-Taos Inc.
>  apm    Applied Micro Circuits Corporation (APM)
>  arm    ARM Ltd.
> --
> 1.8.3.2
>
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
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Re: [PATCH v8 1/2] iio:as3935: Add DT binding docs for AS3935 driver

[Jonathan Cameron]

On 12/03/14 14:30, Rob Herring wrote:
> On Wed, Mar 12, 2014 at 7:53 AM, Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>> Document compatible string, required and optional DT properties for
>> AS3935 chipset driver.
>>
>> Signed-off-by: Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>
> Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Applied to the togreg branch of iio.git (probably pushed out as testing
first to allow the autobuilders to play.

Thanks

Jonathan
>
>> ---
>>   .../devicetree/bindings/iio/proximity/as3935.txt   | 28 ++++++++++++++++++++++
>>   .../devicetree/bindings/vendor-prefixes.txt        |  1 +
>>   2 files changed, 29 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/iio/proximity/as3935.txt
>>
>> diff --git a/Documentation/devicetree/bindings/iio/proximity/as3935.txt b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
>> new file mode 100644
>> index 0000000..ae23dd8
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
>> @@ -0,0 +1,28 @@
>> +Austrian Microsystems AS3935 Franklin lightning sensor device driver
>> +
>> +Required properties:
>> +       - compatible: must be "ams,as3935"
>> +       - reg: SPI chip select number for the device
>> +       - spi-cpha: SPI Mode 1. Refer to spi/spi-bus.txt for generic SPI
>> +       slave node bindings.
>> +       - interrupt-parent : should be the phandle for the interrupt controller
>> +       - interrupts : the sole interrupt generated by the device
>> +
>> +       Refer to interrupt-controller/interrupts.txt for generic
>> +       interrupt client node bindings.
>> +
>> +Optional properties:
>> +       - ams,tuning-capacitor-pf: Calibration tuning capacitor stepping
>> +         value 0 - 120pF. This will require using the calibration data from
>> +         the manufacturer.
>> +
>> +Example:
>> +
>> +as3935@0 {
>> +       compatible = "ams,as3935";
>> +       reg = <0>;
>> +       spi-cpha;
>> +       interrupt-parent = <&gpio1>;
>> +       interrupts = <16 1>;
>> +       ams,tuning-capacitor-pf = <80>;
>> +};
>> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> index 4685ec3..517831d 100644
>> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
>> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> @@ -11,6 +11,7 @@ ak    Asahi Kasei Corp.
>>   allwinner      Allwinner Technology Co., Ltd.
>>   altr   Altera Corp.
>>   amcc   Applied Micro Circuits Corporation (APM, formally AMCC)
>> +ams    AMS AG
>>   amstaos        AMS-Taos Inc.
>>   apm    Applied Micro Circuits Corporation (APM)
>>   arm    ARM Ltd.
>> --
>> 1.8.3.2
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe devicetree" in
>> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> --
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>

[PATCH v8 2/2] iio: Add AS3935 lightning sensor support

[Matt Ranostay]

AS3935 chipset can detect lightning strikes and reports those back as
events and the estimated distance to the storm.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
---
 .../ABI/testing/sysfs-bus-iio-proximity-as3935     |  16 +
 drivers/iio/Kconfig                                |   1 +
 drivers/iio/Makefile                               |   1 +
 drivers/iio/proximity/Kconfig                      |  19 +
 drivers/iio/proximity/Makefile                     |   6 +
 drivers/iio/proximity/as3935.c                     | 456 +++++++++++++++++++++
 6 files changed, 499 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
 create mode 100644 drivers/iio/proximity/Kconfig
 create mode 100644 drivers/iio/proximity/Makefile
 create mode 100644 drivers/iio/proximity/as3935.c

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935 b/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
new file mode 100644
index 0000000..6708c5e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
@@ -0,0 +1,16 @@
+What		/sys/bus/iio/devices/iio:deviceX/in_proximity_raw
+Date:		March 2014
+KernelVersion:	3.15
+Contact:	Matt Ranostay <mranostay@gmail.com>
+Description:
+		Get the current distance in meters of storm (1km steps)
+		1000-40000 = distance in meters
+
+What		/sys/bus/iio/devices/iio:deviceX/sensor_sensitivity
+Date:		March 2014
+KernelVersion:	3.15
+Contact:	Matt Ranostay <mranostay@gmail.com>
+Description:
+		Show or set the gain boost of the amp, from 0-31 range.
+		18 = indoors (default)
+		14 = outdoors
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index 5dd0e12..743485e 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -74,6 +74,7 @@ if IIO_TRIGGER
    source "drivers/iio/trigger/Kconfig"
 endif #IIO_TRIGGER
 source "drivers/iio/pressure/Kconfig"
+source "drivers/iio/proximity/Kconfig"
 source "drivers/iio/temperature/Kconfig"
 
 endif # IIO
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index 887d390..698afc2 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -24,5 +24,6 @@ obj-y += light/
 obj-y += magnetometer/
 obj-y += orientation/
 obj-y += pressure/
+obj-y += proximity/
 obj-y += temperature/
 obj-y += trigger/
diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
new file mode 100644
index 0000000..0c8cdf5
--- /dev/null
+++ b/drivers/iio/proximity/Kconfig
@@ -0,0 +1,19 @@
+#
+# Proximity sensors
+#
+
+menu "Lightning sensors"
+
+config AS3935
+	tristate "AS3935 Franklin lightning sensor"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	depends on SPI
+	help
+	  Say Y here to build SPI interface support for the Austrian
+	  Microsystems AS3935 lightning detection sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called as3935
+
+endmenu
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
new file mode 100644
index 0000000..743adee
--- /dev/null
+++ b/drivers/iio/proximity/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for IIO proximity sensors
+#
+
+# When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_AS3935)		+= as3935.o
diff --git a/drivers/iio/proximity/as3935.c b/drivers/iio/proximity/as3935.c
new file mode 100644
index 0000000..62f5b2d
--- /dev/null
+++ b/drivers/iio/proximity/as3935.c
@@ -0,0 +1,456 @@
+/*
+ * as3935.c - Support for AS3935 Franklin lightning sensor
+ *
+ * Copyright (C) 2014 Matt Ranostay <mranostay@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.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/gpio.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>
+#include <linux/of_gpio.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_INT		0x03
+#define AS3935_INT_MASK		0x07
+#define AS3935_EVENT_INT	BIT(3)
+#define AS3935_NOISE_INT	BIT(1)
+
+#define AS3935_DATA		0x07
+#define AS3935_DATA_MASK	0x3F
+
+#define AS3935_TUNE_CAP		0x08
+#define AS3935_CALIBRATE	0x3D
+
+#define AS3935_WRITE_DATA	BIT(15)
+#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;
+
+	u32 tune_cap;
+	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),
+		.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_WRITE_DATA | 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 IIO_DEVICE_ATTR(sensor_sensitivity, S_IRUGO | S_IWUSR,
+	as3935_sensor_sensitivity_show, as3935_sensor_sensitivity_store, 0);
+
+
+static struct attribute *as3935_attributes[] = {
+	&iio_dev_attr_sensor_sensitivity.dev_attr.attr,
+	NULL,
+};
+
+static 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;
+
+		if (m == IIO_CHAN_INFO_RAW)
+			return IIO_VAL_INT;
+
+		/* storm out of range */
+		if (*val == AS3935_DATA_MASK)
+			return -EINVAL;
+		*val *= 1000;
+		break;
+	default:
+		return -EINVAL;
+	};
+
+	return IIO_VAL_INT;
+}
+
+static const struct iio_info as3935_info = {
+	.driver_module = THIS_MODULE,
+	.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;
+	val &= AS3935_DATA_MASK;
+	val *= 1000;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &val, pf->timestamp);
+err_read:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+};
+
+static const struct iio_trigger_ops iio_interrupt_trigger_ops = {
+	.owner = THIS_MODULE,
+};
+
+static void as3935_event_work(struct work_struct *work)
+{
+	struct as3935_state *st;
+	int val;
+
+	st = container_of(work, struct as3935_state, work.work);
+
+	as3935_read(st, AS3935_INT, &val);
+	val &= AS3935_INT_MASK;
+
+	switch (val) {
+	case AS3935_EVENT_INT:
+		iio_trigger_poll(st->trig, iio_get_time_ns());
+		break;
+	case AS3935_NOISE_INT:
+		dev_warn(&st->spi->dev, "noise level is too high");
+		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)
+{
+	mutex_lock(&st->lock);
+
+	/* mask disturber interrupt bit */
+	as3935_write(st, AS3935_INT, BIT(5));
+
+	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));
+
+	mutex_unlock(&st->lock);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int as3935_suspend(struct spi_device *spi, pm_message_t msg)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	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 spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	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);
+
+err_resume:
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+#else
+#define as3935_suspend	NULL
+#define as3935_resume	NULL
+#endif
+
+static int as3935_probe(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev;
+	struct iio_trigger *trig;
+	struct as3935_state *st;
+	struct device_node *np = spi->dev.of_node;
+	int ret;
+
+	/* Be sure lightning event interrupt is specified */
+	if (!spi->irq) {
+		dev_err(&spi->dev, "unable to get event interrupt\n");
+		return -EINVAL;
+	}
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->spi = spi;
+	st->tune_cap = 0;
+
+	spi_set_drvdata(spi, indio_dev);
+	mutex_init(&st->lock);
+	INIT_DELAYED_WORK(&st->work, as3935_event_work);
+
+	ret = of_property_read_u32(np,
+			"ams,tuning-capacitor-pf", &st->tune_cap);
+	if (ret) {
+		st->tune_cap = 0;
+		dev_warn(&spi->dev,
+			"no tuning-capacitor-pf set, defaulting to %d",
+			st->tune_cap);
+	}
+
+	if (st->tune_cap > MAX_PF_CAP) {
+		dev_err(&spi->dev,
+			"wrong tuning-capacitor-pf setting of %d\n",
+			st->tune_cap);
+		return -EINVAL;
+	}
+
+	indio_dev->dev.parent = &spi->dev;
+	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(&spi->dev, "%s-dev%d",
+				      indio_dev->name, indio_dev->id);
+
+	if (!trig)
+		return -ENOMEM;
+
+	st->trig = trig;
+	trig->dev.parent = indio_dev->dev.parent;
+	iio_trigger_set_drvdata(trig, indio_dev);
+	trig->ops = &iio_interrupt_trigger_ops;
+
+	ret = iio_trigger_register(trig);
+	if (ret) {
+		dev_err(&spi->dev, "failed to register trigger\n");
+		return ret;
+	}
+
+	ret = iio_triggered_buffer_setup(indio_dev, NULL,
+		&as3935_trigger_handler, NULL);
+
+	if (ret) {
+		dev_err(&spi->dev, "cannot setup iio trigger\n");
+		goto unregister_trigger;
+	}
+
+	calibrate_as3935(st);
+
+	ret = devm_request_irq(&spi->dev, spi->irq,
+				&as3935_interrupt_handler,
+				IRQF_TRIGGER_RISING,
+				dev_name(&spi->dev),
+				indio_dev);
+
+	if (ret) {
+		dev_err(&spi->dev, "unable to request irq\n");
+		goto unregister_buffer;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&spi->dev, "unable to register device\n");
+		goto unregister_buffer;
+	}
+	return 0;
+
+unregister_buffer:
+	iio_triggered_buffer_cleanup(indio_dev);
+
+unregister_trigger:
+	iio_trigger_unregister(st->trig);
+
+	return ret;
+};
+
+static int as3935_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct as3935_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+	iio_trigger_unregister(st->trig);
+
+	return 0;
+};
+
+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",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= as3935_probe,
+	.remove		= as3935_remove,
+	.id_table	= as3935_id,
+	.suspend	= as3935_suspend,
+	.resume		= as3935_resume,
+};
+module_spi_driver(as3935_driver);
+
+MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
+MODULE_DESCRIPTION("AS3935 lightning sensor");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:as3935");
-- 
1.8.3.2

Re: [PATCH v8 2/2] iio: Add AS3935 lightning sensor support

[Marek Vasut]

On Wednesday, March 12, 2014 at 01:53:14 PM, Matt Ranostay wrote:
> AS3935 chipset can detect lightning strikes and reports those back as
> events and the estimated distance to the storm.
> 
> Signed-off-by: Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Reviewed-by: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>

Best regards,
Marek Vasut

Re: [PATCH v8 2/2] iio: Add AS3935 lightning sensor support

[Jonathan Cameron]

On 13/03/14 02:09, Marek Vasut wrote:
> On Wednesday, March 12, 2014 at 01:53:14 PM, Matt Ranostay wrote:
>> AS3935 chipset can detect lightning strikes and reports those back as
>> events and the estimated distance to the storm.
>>
>> Signed-off-by: Matt Ranostay <mranostay-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>
> Reviewed-by: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
I'm not 100% happy with sensor_sensitivity but don't have a better idea.
As it is device specific lets leave it be for now.   Should we come
up with a better idea later it isn't much extra code to keep supporting
this interface going forwards.

Applied to the togreg branch of iio.git (pushed out initially as testing)

Thanks,

Jonathan