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authorMatt Ranostay <matt.ranostay@konsulko.com>2017-05-25 08:52:29 +0300
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2017-09-25 21:49:21 +0300
commiteb35279dd7c7834d6320edf24e1b9786d31e4899 (patch)
tree2db4d76fee1cdccd2483ca5e12a05bf4e6597806
parentb2e312061c5e9f533c44487862dc405094bf250a (diff)
downloadlinux-eb35279dd7c7834d6320edf24e1b9786d31e4899.tar.xz
iio: proximity: as3935: noise detection + threshold changes
Most applications are too noisy to allow the default noise and watchdog settings, and thus need to be configurable via DT properties. Also default settings to POR defaults on a reset, and register distuber interrupts as noise since it prevents proper usage. Cc: devicetree@vger.kernel.org Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
-rw-r--r--Documentation/ABI/testing/sysfs-bus-iio-proximity-as39358
-rw-r--r--Documentation/devicetree/bindings/iio/proximity/as3935.txt5
-rw-r--r--drivers/iio/proximity/as3935.c43
3 files changed, 53 insertions, 3 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935 b/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
index 33e96f740639..147d4e8a1403 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
+++ b/Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935
@@ -14,3 +14,11 @@ Description:
Show or set the gain boost of the amp, from 0-31 range.
18 = indoors (default)
14 = outdoors
+
+What /sys/bus/iio/devices/iio:deviceX/noise_level_tripped
+Date: May 2017
+KernelVersion: 4.13
+Contact: Matt Ranostay <matt.ranostay@konsulko.com>
+Description:
+ When 1 the noise level is over the trip level and not reporting
+ valid data
diff --git a/Documentation/devicetree/bindings/iio/proximity/as3935.txt b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
index 38d74314b7ab..b6c1afa6f02d 100644
--- a/Documentation/devicetree/bindings/iio/proximity/as3935.txt
+++ b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
@@ -16,6 +16,10 @@ Optional properties:
- ams,tuning-capacitor-pf: Calibration tuning capacitor stepping
value 0 - 120pF. This will require using the calibration data from
the manufacturer.
+ - ams,nflwdth: Set the noise and watchdog threshold register on
+ startup. This will need to set according to the noise from the
+ MCU board, and possibly the local environment. Refer to the
+ datasheet for the threshold settings.
Example:
@@ -27,4 +31,5 @@ as3935@0 {
interrupt-parent = <&gpio1>;
interrupts = <16 1>;
ams,tuning-capacitor-pf = <80>;
+ ams,nflwdth = <0x44>;
};
diff --git a/drivers/iio/proximity/as3935.c b/drivers/iio/proximity/as3935.c
index 0eeff29b61be..4a48b7ba3a1c 100644
--- a/drivers/iio/proximity/as3935.c
+++ b/drivers/iio/proximity/as3935.c
@@ -39,8 +39,12 @@
#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)
@@ -48,6 +52,7 @@
#define AS3935_DATA_MASK 0x3F
#define AS3935_TUNE_CAP 0x08
+#define AS3935_DEFAULTS 0x3C
#define AS3935_CALIBRATE 0x3D
#define AS3935_READ_DATA BIT(14)
@@ -62,7 +67,9 @@ struct as3935_state {
struct mutex lock;
struct delayed_work work;
+ unsigned long noise_tripped;
u32 tune_cap;
+ u32 nflwdth_reg;
u8 buffer[16]; /* 8-bit data + 56-bit padding + 64-bit timestamp */
u8 buf[2] ____cacheline_aligned;
};
@@ -145,12 +152,29 @@ static ssize_t as3935_sensor_sensitivity_store(struct device *dev,
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,
};
@@ -246,7 +270,11 @@ static void as3935_event_work(struct work_struct *work)
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;
}
@@ -269,15 +297,14 @@ static irqreturn_t as3935_interrupt_handler(int irq, void *private)
static void calibrate_as3935(struct as3935_state *st)
{
- /* mask disturber interrupt bit */
- as3935_write(st, AS3935_INT, BIT(5));
-
+ 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
@@ -370,6 +397,15 @@ static int as3935_probe(struct spi_device *spi)
return -EINVAL;
}
+ ret = of_property_read_u32(np,
+ "ams,nflwdth", &st->nflwdth_reg);
+ if (!ret && st->nflwdth_reg > AS3935_NFLWDTH_MASK) {
+ dev_err(&spi->dev,
+ "invalid nflwdth setting of %d\n",
+ st->nflwdth_reg);
+ return -EINVAL;
+ }
+
indio_dev->dev.parent = &spi->dev;
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->channels = as3935_channels;
@@ -384,6 +420,7 @@ static int as3935_probe(struct spi_device *spi)
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;