[deliverable/linux.git] / drivers / iio / light / acpi-als.c

/*
 * ACPI Ambient Light Sensor Driver
 *
 * Based on ALS driver:
 * Copyright (C) 2009 Zhang Rui <rui.zhang@intel.com>
 *
 * Rework for IIO subsystem:
 * Copyright (C) 2012-2013 Martin Liska <marxin.liska@gmail.com>
 *
 * Final cleanup and debugging:
 * Copyright (C) 2013-2014 Marek Vasut <marex@denx.de>
 * Copyright (C) 2015 Gabriele Mazzotta <gabriele.mzt@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.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/err.h>
#include <linux/mutex.h>

#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>

#define ACPI_ALS_CLASS			"als"
#define ACPI_ALS_DEVICE_NAME		"acpi-als"
#define ACPI_ALS_NOTIFY_ILLUMINANCE	0x80

ACPI_MODULE_NAME("acpi-als");

/*
 * So far, there's only one channel in here, but the specification for
 * ACPI0008 says there can be more to what the block can report. Like
 * chromaticity and such. We are ready for incoming additions!
 */
static const struct iio_chan_spec acpi_als_channels[] = {
	{
		.type		= IIO_LIGHT,
		.scan_type	= {
			.sign		= 's',
			.realbits	= 32,
			.storagebits	= 32,
		},
		/* _RAW is here for backward ABI compatibility */
		.info_mask_separate	= BIT(IIO_CHAN_INFO_RAW) |
					  BIT(IIO_CHAN_INFO_PROCESSED),
	},
};

/*
 * The event buffer contains timestamp and all the data from
 * the ACPI0008 block. There are multiple, but so far we only
 * support _ALI (illuminance). Once someone adds new channels
 * to acpi_als_channels[], the evt_buffer below will grow
 * automatically.
 */
#define ACPI_ALS_EVT_NR_SOURCES		ARRAY_SIZE(acpi_als_channels)
#define ACPI_ALS_EVT_BUFFER_SIZE		\
	(sizeof(s64) + (ACPI_ALS_EVT_NR_SOURCES * sizeof(s32)))

struct acpi_als {
	struct acpi_device	*device;
	struct mutex		lock;

	s32			evt_buffer[ACPI_ALS_EVT_BUFFER_SIZE];
};

/*
 * All types of properties the ACPI0008 block can report. The ALI, ALC, ALT
 * and ALP can all be handled by acpi_als_read_value() below, while the ALR is
 * special.
 *
 * The _ALR property returns tables that can be used to fine-tune the values
 * reported by the other props based on the particular hardware type and it's
 * location (it contains tables for "rainy", "bright inhouse lighting" etc.).
 *
 * So far, we support only ALI (illuminance).
 */
#define ACPI_ALS_ILLUMINANCE	"_ALI"
#define ACPI_ALS_CHROMATICITY	"_ALC"
#define ACPI_ALS_COLOR_TEMP	"_ALT"
#define ACPI_ALS_POLLING	"_ALP"
#define ACPI_ALS_TABLES		"_ALR"

static int acpi_als_read_value(struct acpi_als *als, char *prop, s32 *val)
{
	unsigned long long temp_val;
	acpi_status status;

	status = acpi_evaluate_integer(als->device->handle, prop, NULL,
				       &temp_val);

	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Error reading ALS %s", prop));
		return -EIO;
	}

	*val = temp_val;

	return 0;
}

static void acpi_als_notify(struct acpi_device *device, u32 event)
{
	struct iio_dev *indio_dev = acpi_driver_data(device);
	struct acpi_als *als = iio_priv(indio_dev);
	s32 *buffer = als->evt_buffer;
	s64 time_ns = iio_get_time_ns();
	s32 val;
	int ret;

	mutex_lock(&als->lock);

	memset(buffer, 0, ACPI_ALS_EVT_BUFFER_SIZE);

	switch (event) {
	case ACPI_ALS_NOTIFY_ILLUMINANCE:
		ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &val);
		if (ret < 0)
			goto out;
		*buffer++ = val;
		break;
	default:
		/* Unhandled event */
		dev_dbg(&device->dev, "Unhandled ACPI ALS event (%08x)!\n",
			event);
		goto out;
	}

	iio_push_to_buffers_with_timestamp(indio_dev, als->evt_buffer, time_ns);

out:
	mutex_unlock(&als->lock);
}

static int acpi_als_read_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan, int *val,
			     int *val2, long mask)
{
	struct acpi_als *als = iio_priv(indio_dev);
	s32 temp_val;
	int ret;

	if ((mask != IIO_CHAN_INFO_PROCESSED) && (mask != IIO_CHAN_INFO_RAW))
		return -EINVAL;

	/* we support only illumination (_ALI) so far. */
	if (chan->type != IIO_LIGHT)
		return -EINVAL;

	ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &temp_val);
	if (ret < 0)
		return ret;

	*val = temp_val;

	return IIO_VAL_INT;
}

static const struct iio_info acpi_als_info = {
	.driver_module		= THIS_MODULE,
	.read_raw		= acpi_als_read_raw,
};

static int acpi_als_add(struct acpi_device *device)
{
	struct acpi_als *als;
	struct iio_dev *indio_dev;
	struct iio_buffer *buffer;

	indio_dev = devm_iio_device_alloc(&device->dev, sizeof(*als));
	if (!indio_dev)
		return -ENOMEM;

	als = iio_priv(indio_dev);

	device->driver_data = indio_dev;
	als->device = device;
	mutex_init(&als->lock);

	indio_dev->name = ACPI_ALS_DEVICE_NAME;
	indio_dev->dev.parent = &device->dev;
	indio_dev->info = &acpi_als_info;
	indio_dev->modes = INDIO_BUFFER_SOFTWARE;
	indio_dev->channels = acpi_als_channels;
	indio_dev->num_channels = ARRAY_SIZE(acpi_als_channels);

	buffer = devm_iio_kfifo_allocate(&device->dev);
	if (!buffer)
		return -ENOMEM;

	iio_device_attach_buffer(indio_dev, buffer);

	return devm_iio_device_register(&device->dev, indio_dev);
}

static const struct acpi_device_id acpi_als_device_ids[] = {
	{"ACPI0008", 0},
	{},
};

MODULE_DEVICE_TABLE(acpi, acpi_als_device_ids);

static struct acpi_driver acpi_als_driver = {
	.name	= "acpi_als",
	.class	= ACPI_ALS_CLASS,
	.ids	= acpi_als_device_ids,
	.ops = {
		.add	= acpi_als_add,
		.notify	= acpi_als_notify,
	},
};

module_acpi_driver(acpi_als_driver);

MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
MODULE_AUTHOR("Martin Liska <marxin.liska@gmail.com>");
MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
MODULE_DESCRIPTION("ACPI Ambient Light Sensor Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
feca56ff GM	1	/*
	2	* ACPI Ambient Light Sensor Driver
	3	*
	4	* Based on ALS driver:
	5	* Copyright (C) 2009 Zhang Rui <rui.zhang@intel.com>
	6	*
	7	* Rework for IIO subsystem:
	8	* Copyright (C) 2012-2013 Martin Liska <marxin.liska@gmail.com>
	9	*
	10	* Final cleanup and debugging:
	11	* Copyright (C) 2013-2014 Marek Vasut <marex@denx.de>
	12	* Copyright (C) 2015 Gabriele Mazzotta <gabriele.mzt@gmail.com>
	13	*
	14	* This program is free software; you can redistribute it and/or modify it
	15	* under the terms of the GNU General Public License as published by the
	16	* Free Software Foundation; either version 2 of the License, or (at your
	17	* option) any later version.
	18	*
	19	* This program is distributed in the hope that it will be useful, but
	20	* WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	22	* General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License along
	25	* with this program; if not, write to the Free Software Foundation, Inc.,
	26	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	27	*/
	28
	29	#include <linux/module.h>
	30	#include <linux/acpi.h>
	31	#include <linux/err.h>
	32	#include <linux/mutex.h>
	33
	34	#include <linux/iio/iio.h>
	35	#include <linux/iio/buffer.h>
	36	#include <linux/iio/kfifo_buf.h>
	37
	38	#define ACPI_ALS_CLASS "als"
	39	#define ACPI_ALS_DEVICE_NAME "acpi-als"
	40	#define ACPI_ALS_NOTIFY_ILLUMINANCE 0x80
	41
	42	ACPI_MODULE_NAME("acpi-als");
	43
	44	/*
	45	* So far, there's only one channel in here, but the specification for
	46	* ACPI0008 says there can be more to what the block can report. Like
	47	* chromaticity and such. We are ready for incoming additions!
	48	*/
	49	static const struct iio_chan_spec acpi_als_channels[] = {
	50	{
	51	.type = IIO_LIGHT,
	52	.scan_type = {
	53	.sign = 's',
	54	.realbits = 32,
	55	.storagebits = 32,
	56	},
fa34e6dd GM	57	/* _RAW is here for backward ABI compatibility */
	58	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \|
	59	BIT(IIO_CHAN_INFO_PROCESSED),
feca56ff GM	60	},
	61	};
	62
	63	/*
	64	* The event buffer contains timestamp and all the data from
	65	* the ACPI0008 block. There are multiple, but so far we only
	66	* support _ALI (illuminance). Once someone adds new channels
	67	* to acpi_als_channels[], the evt_buffer below will grow
	68	* automatically.
	69	*/
23633314 HK	70	#define ACPI_ALS_EVT_NR_SOURCES ARRAY_SIZE(acpi_als_channels)
	71	#define ACPI_ALS_EVT_BUFFER_SIZE \
	72	(sizeof(s64) + (ACPI_ALS_EVT_NR_SOURCES * sizeof(s32)))
feca56ff GM	73
	74	struct acpi_als {
	75	struct acpi_device *device;
	76	struct mutex lock;
	77
23633314	78	s32 evt_buffer[ACPI_ALS_EVT_BUFFER_SIZE];
feca56ff GM	79	};
	80
	81	/*
	82	* All types of properties the ACPI0008 block can report. The ALI, ALC, ALT
23633314	83	* and ALP can all be handled by acpi_als_read_value() below, while the ALR is
feca56ff GM	84	* special.
	85	*
	86	* The _ALR property returns tables that can be used to fine-tune the values
	87	* reported by the other props based on the particular hardware type and it's
	88	* location (it contains tables for "rainy", "bright inhouse lighting" etc.).
	89	*
	90	* So far, we support only ALI (illuminance).
	91	*/
	92	#define ACPI_ALS_ILLUMINANCE "_ALI"
	93	#define ACPI_ALS_CHROMATICITY "_ALC"
	94	#define ACPI_ALS_COLOR_TEMP "_ALT"
	95	#define ACPI_ALS_POLLING "_ALP"
	96	#define ACPI_ALS_TABLES "_ALR"
	97
23633314	98	static int acpi_als_read_value(struct acpi_als als, char prop, s32 *val)
feca56ff GM	99	{
	100	unsigned long long temp_val;
	101	acpi_status status;
	102
	103	status = acpi_evaluate_integer(als->device->handle, prop, NULL,
	104	&temp_val);
	105
	106	if (ACPI_FAILURE(status)) {
	107	ACPI_EXCEPTION((AE_INFO, status, "Error reading ALS %s", prop));
	108	return -EIO;
	109	}
	110
	111	*val = temp_val;
	112
	113	return 0;
	114	}
	115
	116	static void acpi_als_notify(struct acpi_device *device, u32 event)
	117	{
	118	struct iio_dev *indio_dev = acpi_driver_data(device);
	119	struct acpi_als *als = iio_priv(indio_dev);
	120	s32 *buffer = als->evt_buffer;
	121	s64 time_ns = iio_get_time_ns();
	122	s32 val;
	123	int ret;
	124
	125	mutex_lock(&als->lock);
	126
23633314	127	memset(buffer, 0, ACPI_ALS_EVT_BUFFER_SIZE);
feca56ff GM	128
	129	switch (event) {
	130	case ACPI_ALS_NOTIFY_ILLUMINANCE:
23633314	131	ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &val);
feca56ff GM	132	if (ret < 0)
	133	goto out;
	134	*buffer++ = val;
	135	break;
	136	default:
	137	/* Unhandled event */
	138	dev_dbg(&device->dev, "Unhandled ACPI ALS event (%08x)!\n",
	139	event);
	140	goto out;
	141	}
	142
	143	iio_push_to_buffers_with_timestamp(indio_dev, als->evt_buffer, time_ns);
	144
	145	out:
	146	mutex_unlock(&als->lock);
	147	}
	148
	149	static int acpi_als_read_raw(struct iio_dev *indio_dev,
	150	struct iio_chan_spec const chan, int val,
	151	int *val2, long mask)
	152	{
	153	struct acpi_als *als = iio_priv(indio_dev);
	154	s32 temp_val;
	155	int ret;
	156
fa34e6dd	157	if ((mask != IIO_CHAN_INFO_PROCESSED) && (mask != IIO_CHAN_INFO_RAW))
feca56ff GM	158	return -EINVAL;
	159
	160	/* we support only illumination (_ALI) so far. */
	161	if (chan->type != IIO_LIGHT)
	162	return -EINVAL;
	163
23633314	164	ret = acpi_als_read_value(als, ACPI_ALS_ILLUMINANCE, &temp_val);
feca56ff GM	165	if (ret < 0)
	166	return ret;
	167
	168	*val = temp_val;
	169
	170	return IIO_VAL_INT;
	171	}
	172
	173	static const struct iio_info acpi_als_info = {
	174	.driver_module = THIS_MODULE,
	175	.read_raw = acpi_als_read_raw,
	176	};
	177
	178	static int acpi_als_add(struct acpi_device *device)
	179	{
	180	struct acpi_als *als;
	181	struct iio_dev *indio_dev;
	182	struct iio_buffer *buffer;
	183
	184	indio_dev = devm_iio_device_alloc(&device->dev, sizeof(*als));
	185	if (!indio_dev)
	186	return -ENOMEM;
	187
	188	als = iio_priv(indio_dev);
	189
	190	device->driver_data = indio_dev;
	191	als->device = device;
	192	mutex_init(&als->lock);
	193
	194	indio_dev->name = ACPI_ALS_DEVICE_NAME;
	195	indio_dev->dev.parent = &device->dev;
	196	indio_dev->info = &acpi_als_info;
	197	indio_dev->modes = INDIO_BUFFER_SOFTWARE;
	198	indio_dev->channels = acpi_als_channels;
	199	indio_dev->num_channels = ARRAY_SIZE(acpi_als_channels);
	200
	201	buffer = devm_iio_kfifo_allocate(&device->dev);
	202	if (!buffer)
	203	return -ENOMEM;
	204
	205	iio_device_attach_buffer(indio_dev, buffer);
	206
	207	return devm_iio_device_register(&device->dev, indio_dev);
	208	}
	209
	210	static const struct acpi_device_id acpi_als_device_ids[] = {
	211	{"ACPI0008", 0},
	212	{},
	213	};
	214
	215	MODULE_DEVICE_TABLE(acpi, acpi_als_device_ids);
	216
	217	static struct acpi_driver acpi_als_driver = {
	218	.name = "acpi_als",
	219	.class = ACPI_ALS_CLASS,
	220	.ids = acpi_als_device_ids,
	221	.ops = {
	222	.add = acpi_als_add,
	223	.notify = acpi_als_notify,
	224	},
	225	};
	226
	227	module_acpi_driver(acpi_als_driver);
	228
229	MODULE_AUTHOR("Zhang Rui <rui.zhang@intel.com>");
230	MODULE_AUTHOR("Martin Liska <marxin.liska@gmail.com>");
231	MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
232	MODULE_DESCRIPTION("ACPI Ambient Light Sensor Driver");
233	MODULE_LICENSE("GPL");