Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751848AbaBCKKW (ORCPT ); Mon, 3 Feb 2014 05:10:22 -0500 Received: from ns.pmeerw.net ([87.118.82.44]:51288 "EHLO pmeerw.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751258AbaBCKKT (ORCPT ); Mon, 3 Feb 2014 05:10:19 -0500 Date: Mon, 3 Feb 2014 11:10:15 +0100 (CET) From: Peter Meerwald To: Matt Ranostay cc: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Jonathan Cameron Subject: Re: [PATCH v3 2/3] iio: Add AS3935 lightning sensor support In-Reply-To: <1391235462-32453-2-git-send-email-mranostay@gmail.com> Message-ID: References: <1391235462-32453-1-git-send-email-mranostay@gmail.com> <1391235462-32453-2-git-send-email-mranostay@gmail.com> User-Agent: Alpine 2.01 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, > AS3935 chipset can detect lightning strikes and reports those back as > events and the estimated distance to the storm. couple of more comments: the AS3935 seems to support I2C and SPI, the driver supports SPI only; this should be noted somewhere IIO already has a proximity channel which is somewhat similar; unfortunately, proximity is not really documented in sysfs-bus-iio (proximity seems to be unit-less so far) you propose to add a distance channel with unit of kilometers (which happens to make sense for the as3935 driver); probably distance should be meters, not kilometers sorry to bring this up so late: but what is the argument to have distance and not re-use proximity? some more comments inline below; you have only tested with nearby lightning? :) p. > --- > .../ABI/testing/sysfs-bus-iio-distance-as3935 | 19 + > drivers/iio/Kconfig | 1 + > drivers/iio/Makefile | 1 + > drivers/iio/distance/Kconfig | 19 + > drivers/iio/distance/Makefile | 6 + > drivers/iio/distance/as3935.c | 438 +++++++++++++++++++++ > 6 files changed, 484 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-distance-as3935 > create mode 100644 drivers/iio/distance/Kconfig > create mode 100644 drivers/iio/distance/Makefile > create mode 100644 drivers/iio/distance/as3935.c > > diff --git a/Documentation/ABI/testing/sysfs-bus-iio-distance-as3935 b/Documentation/ABI/testing/sysfs-bus-iio-distance-as3935 > new file mode 100644 > index 0000000..cf9a67c > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-bus-iio-distance-as3935 > @@ -0,0 +1,19 @@ > +What /sys/bus/iio/devices/iio:deviceX/in_distance_raw > +Date: January 2014 > +KernelVersion: 3.15 > +Contact: Matt Ranostay > +Description: > + Get the current distance in kilometers of storm > + 0 = no storm activity > + 1 = storm overhead > + 1-40 = distance in kilometers > + 63 = out of range > + > +What /sys/bus/iio/devices/iio:deviceX/gain_boost > +Date: January 2014 > +KernelVersion: 3.15 > +Contact: Matt Ranostay > +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..5164a68 100644 > --- a/drivers/iio/Kconfig > +++ b/drivers/iio/Kconfig > @@ -63,6 +63,7 @@ source "drivers/iio/adc/Kconfig" > source "drivers/iio/amplifiers/Kconfig" > source "drivers/iio/common/Kconfig" > source "drivers/iio/dac/Kconfig" > +source "drivers/iio/distance/Kconfig" > source "drivers/iio/frequency/Kconfig" > source "drivers/iio/gyro/Kconfig" > source "drivers/iio/humidity/Kconfig" > diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile > index 887d390..1574731 100644 > --- a/drivers/iio/Makefile > +++ b/drivers/iio/Makefile > @@ -16,6 +16,7 @@ obj-y += adc/ > obj-y += amplifiers/ > obj-y += common/ > obj-y += dac/ > +obj-y += distance/ > obj-y += gyro/ > obj-y += frequency/ > obj-y += humidity/ > diff --git a/drivers/iio/distance/Kconfig b/drivers/iio/distance/Kconfig > new file mode 100644 > index 0000000..8a2404c > --- /dev/null > +++ b/drivers/iio/distance/Kconfig > @@ -0,0 +1,19 @@ > +# > +# Distance sensors > +# > + > +menu "Lightning sensors" > + > +config AS3935 > + tristate "AS3935 Franklin lightning sensor" > + select IIO_BUFFER > + select IIO_TRIGGERED_BUFFER > + depends on SPI > + help > + If you say yes here you get support for the Austrian Microsystems > + AS3935 lightning detection sensor. > + > + This driver can also be built as a module. If so, the module > + will be called as3935. > + > +endmenu > diff --git a/drivers/iio/distance/Makefile b/drivers/iio/distance/Makefile > new file mode 100644 > index 0000000..f63b70d > --- /dev/null > +++ b/drivers/iio/distance/Makefile > @@ -0,0 +1,6 @@ > +# > +# Makefile for IIO distance sensors > +# > + > +# When adding new entries keep the list in alphabetical order > +obj-$(CONFIG_AS3935) += as3935.o > diff --git a/drivers/iio/distance/as3935.c b/drivers/iio/distance/as3935.c > new file mode 100644 > index 0000000..ea00cd1 > --- /dev/null > +++ b/drivers/iio/distance/as3935.c > @@ -0,0 +1,438 @@ > +/* > + * as3935.c - Support for AS3935 Franklin lightning sensor > + * > + * Copyright (C) 2014 Matt Ranostay > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > + > +#define AS3935_AFE_GAIN 0x00 > +#define AS3935_AFE_MASK 0x3F > +#define AS3935_AFE_GAIN_MAX 0x1F > +#define AS3935_AFE_PWR_BIT (1<<0) > + > +#define AS3935_INT 0x03 > +#define AS3935_INT_MASK 0x07 > +#define AS3935_EVENT_INT (1<<3) > +#define AS3935_NOISE_INT (1<<0) you could use BIT(3), BIT(0) etc. > + > +#define AS3935_DATA 0x07 > +#define AS3935_DATA_MASK 0x1F > + > +#define AS3935_TUNE_CAP 0x08 > +#define AS3935_CALIBRATE 0x3D > + > +#define AS3935_WRITE_DATA (0x1 << 15) > +#define AS3935_READ_DATA (0x1 << 14) > +#define AS3935_ADDRESS(x) (x << 8) > + > +struct as3935_state { > + struct spi_device *spi; > + struct iio_trigger *trig; > + struct mutex lock; > + struct delayed_work work; > + > + u8 tune_cap; > +}; > + > +static const struct iio_chan_spec as3935_channels[] = { > + { > + .type = IIO_DISTANCE, > + .info_mask_separate = > + BIT(IIO_CHAN_INFO_RAW), > + .scan_index = 0, > + .scan_type = { > + .sign = 'u', > + .realbits = 8, realbits should be 6 DATA_MASK should be 0x3f, not 0x1f > + .storagebits = 8, > + }, > + }, > + IIO_CHAN_SOFT_TIMESTAMP(1), > +}; > + > +static int as3935_read(struct as3935_state *st, unsigned int reg, int *val) > +{ > + u8 tx, rx; > + int ret; > + > + struct spi_transfer xfers[] = { > + { > + .tx_buf = &tx, > + .bits_per_word = 8, > + .len = 1, > + }, { > + .rx_buf = &rx, > + .bits_per_word = 8, > + .len = 1, > + }, > + }; > + tx = (AS3935_READ_DATA | AS3935_ADDRESS(reg)) >> 8; > + > + ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers)); > + *val = rx; > + > + return ret; > +}; > + > +static int as3935_write(struct as3935_state *st, > + unsigned int reg, > + unsigned int val) > +{ > + u8 buf[2]; > + > + buf[0] = AS3935_WRITE_DATA | AS3935_ADDRESS(reg) >> 8; > + buf[1] = val; > + > + return spi_write(st->spi, (u8 *) &buf, 2); > +}; > + > +static ssize_t as3935_gain_boost_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_gain_boost_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(gain_boost, S_IRUGO | S_IWUSR, > + as3935_gain_boost_show, as3935_gain_boost_store, 0); > + > + > +static struct attribute *as3935_attributes[] = { > + &iio_dev_attr_gain_boost.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; > + > + if (m != IIO_CHAN_INFO_RAW) > + return -EINVAL; > + > + *val2 = 0; > + ret = as3935_read(st, AS3935_DATA, val); > + if (ret) > + return ret; > + 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 const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { > + .postenable = &iio_triggered_buffer_postenable, > + .predisable = &iio_triggered_buffer_predisable, > +}; > + > +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; > + iio_push_to_buffers_with_timestamp(indio_dev, &val, iio_get_time_ns()); > +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; > + struct spi_device *spi; > + int val; > + > + st = container_of(work, struct as3935_state, work.work); > + spi = st->spi; > + > + as3935_read(st, AS3935_INT, &val); > + val &= AS3935_INT_MASK; > + > + switch (val) { > + case AS3935_EVENT_INT: > + iio_trigger_poll(st->trig, 0); > + break; > + case AS3935_NOISE_INT: > + dev_warn(&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); > + > + cancel_delayed_work(&st->work); > + schedule_delayed_work(&st->work, jiffies_to_msecs(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, 1 << 5); > + > + as3935_write(st, AS3935_CALIBRATE, 0x96); > + as3935_write(st, AS3935_TUNE_CAP, 1 << 5 | st->tune_cap); > + > + mdelay(2); > + as3935_write(st, AS3935_TUNE_CAP, st->tune_cap); > + > + 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) > + return ret; > + val |= AS3935_AFE_PWR_BIT; > + > + ret = as3935_write(st, AS3935_AFE_GAIN, val); > + 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) > + return ret; > + val &= ~AS3935_AFE_PWR_BIT; > + ret = as3935_write(st, AS3935_AFE_GAIN, val); > + 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 */ > + 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_u8(np, "ams,tune-cap", &st->tune_cap); > + if (ret) { > + st->tune_cap = 0; > + dev_warn(&spi->dev, > + "no tune-cap set, defaulting to %d", st->tune_cap); > + } > + > + if (st->tune_cap > 15) { > + dev_err(&spi->dev, > + "wrong tune-cap 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, > + &iio_triggered_buffer_setup_ops); > + > + 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_trigger; > + } > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&spi->dev, "unable to register device\n"); > + goto unregister_trigger; > + } > + > + return 0; > + > +unregister_trigger: > + iio_trigger_unregister(st->trig); > + iio_triggered_buffer_cleanup(indio_dev); > + > + 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_trigger_unregister(st->trig); > + iio_triggered_buffer_cleanup(indio_dev); > + iio_device_unregister(indio_dev); > + > + 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 "); > +MODULE_DESCRIPTION("AS3935 lightning sensor"); > +MODULE_LICENSE("GPL"); > +MODULE_ALIAS("spi:as3935"); > -- Peter Meerwald +43-664-2444418 (mobile) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/