[linux-2.6-block.git] / drivers / hwmon / adcxx.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * adcxx.c
 *
 * The adcxx4s is an AD converter family from National Semiconductor (NS).
 *
 * Copyright (c) 2008 Marc Pignat <marc.pignat@hevs.ch>
 *
 * The adcxx4s communicates with a host processor via an SPI/Microwire Bus
 * interface. This driver supports the whole family of devices with name
 * ADC<bb><c>S<sss>, where
 * * bb is the resolution in number of bits (8, 10, 12)
 * * c is the number of channels (1, 2, 4, 8)
 * * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500 kSPS
 *   and 101 for 1 MSPS)
 *
 * Complete datasheets are available at National's website here:
 * http://www.national.com/ds/DC/ADC<bb><c>S<sss>.pdf
 *
 * Handling of 8, 10 and 12 bits converters are the same, the
 * unavailable bits are 0 :)
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/sysfs.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/mutex.h>
#include <linux/mod_devicetable.h>
#include <linux/spi/spi.h>

#define DRVNAME		"adcxx"

struct adcxx {
	struct device *hwmon_dev;
	struct mutex lock;
	u32 channels;
	u32 reference; /* in millivolts */
};

/* sysfs hook function */
static ssize_t adcxx_show(struct device *dev,
			  struct device_attribute *devattr, char *buf)
{
	struct spi_device *spi = to_spi_device(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct adcxx *adc = spi_get_drvdata(spi);
	u8 tx_buf[2];
	u8 rx_buf[2];
	int status;
	u32 value;

	if (mutex_lock_interruptible(&adc->lock))
		return -ERESTARTSYS;

	if (adc->channels == 1) {
		status = spi_read(spi, rx_buf, sizeof(rx_buf));
	} else {
		tx_buf[0] = attr->index << 3; /* other bits are don't care */
		status = spi_write_then_read(spi, tx_buf, sizeof(tx_buf),
						rx_buf, sizeof(rx_buf));
	}
	if (status < 0) {
		dev_warn(dev, "SPI synch. transfer failed with status %d\n",
				status);
		goto out;
	}

	value = (rx_buf[0] << 8) + rx_buf[1];
	dev_dbg(dev, "raw value = 0x%x\n", value);

	value = value * adc->reference >> 12;
	status = sprintf(buf, "%d\n", value);
out:
	mutex_unlock(&adc->lock);
	return status;
}

static ssize_t adcxx_min_show(struct device *dev,
			      struct device_attribute *devattr, char *buf)
{
	/* The minimum reference is 0 for this chip family */
	return sprintf(buf, "0\n");
}

static ssize_t adcxx_max_show(struct device *dev,
			      struct device_attribute *devattr, char *buf)
{
	struct spi_device *spi = to_spi_device(dev);
	struct adcxx *adc = spi_get_drvdata(spi);
	u32 reference;

	if (mutex_lock_interruptible(&adc->lock))
		return -ERESTARTSYS;

	reference = adc->reference;

	mutex_unlock(&adc->lock);

	return sprintf(buf, "%d\n", reference);
}

static ssize_t adcxx_max_store(struct device *dev,
			       struct device_attribute *devattr,
			       const char *buf, size_t count)
{
	struct spi_device *spi = to_spi_device(dev);
	struct adcxx *adc = spi_get_drvdata(spi);
	unsigned long value;

	if (kstrtoul(buf, 10, &value))
		return -EINVAL;

	if (mutex_lock_interruptible(&adc->lock))
		return -ERESTARTSYS;

	adc->reference = value;

	mutex_unlock(&adc->lock);

	return count;
}

static ssize_t adcxx_name_show(struct device *dev,
			       struct device_attribute *devattr, char *buf)
{
	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
}

static struct sensor_device_attribute ad_input[] = {
	SENSOR_ATTR_RO(name, adcxx_name, 0),
	SENSOR_ATTR_RO(in_min, adcxx_min, 0),
	SENSOR_ATTR_RW(in_max, adcxx_max, 0),
	SENSOR_ATTR_RO(in0_input, adcxx, 0),
	SENSOR_ATTR_RO(in1_input, adcxx, 1),
	SENSOR_ATTR_RO(in2_input, adcxx, 2),
	SENSOR_ATTR_RO(in3_input, adcxx, 3),
	SENSOR_ATTR_RO(in4_input, adcxx, 4),
	SENSOR_ATTR_RO(in5_input, adcxx, 5),
	SENSOR_ATTR_RO(in6_input, adcxx, 6),
	SENSOR_ATTR_RO(in7_input, adcxx, 7),
};

/*----------------------------------------------------------------------*/

static int adcxx_probe(struct spi_device *spi)
{
	int channels = spi_get_device_id(spi)->driver_data;
	struct adcxx *adc;
	int status;
	int i;

	adc = devm_kzalloc(&spi->dev, sizeof(*adc), GFP_KERNEL);
	if (!adc)
		return -ENOMEM;

	/* set a default value for the reference */
	adc->reference = 3300;
	adc->channels = channels;
	mutex_init(&adc->lock);

	mutex_lock(&adc->lock);

	spi_set_drvdata(spi, adc);

	for (i = 0; i < 3 + adc->channels; i++) {
		status = device_create_file(&spi->dev, &ad_input[i].dev_attr);
		if (status) {
			dev_err(&spi->dev, "device_create_file failed.\n");
			goto out_err;
		}
	}

	adc->hwmon_dev = hwmon_device_register(&spi->dev);
	if (IS_ERR(adc->hwmon_dev)) {
		dev_err(&spi->dev, "hwmon_device_register failed.\n");
		status = PTR_ERR(adc->hwmon_dev);
		goto out_err;
	}

	mutex_unlock(&adc->lock);
	return 0;

out_err:
	for (i--; i >= 0; i--)
		device_remove_file(&spi->dev, &ad_input[i].dev_attr);

	mutex_unlock(&adc->lock);
	return status;
}

static int adcxx_remove(struct spi_device *spi)
{
	struct adcxx *adc = spi_get_drvdata(spi);
	int i;

	mutex_lock(&adc->lock);
	hwmon_device_unregister(adc->hwmon_dev);
	for (i = 0; i < 3 + adc->channels; i++)
		device_remove_file(&spi->dev, &ad_input[i].dev_attr);

	mutex_unlock(&adc->lock);

	return 0;
}

static const struct spi_device_id adcxx_ids[] = {
	{ "adcxx1s", 1 },
	{ "adcxx2s", 2 },
	{ "adcxx4s", 4 },
	{ "adcxx8s", 8 },
	{ },
};
MODULE_DEVICE_TABLE(spi, adcxx_ids);

static struct spi_driver adcxx_driver = {
	.driver = {
		.name	= "adcxx",
	},
	.id_table = adcxx_ids,
	.probe	= adcxx_probe,
	.remove	= adcxx_remove,
};

module_spi_driver(adcxx_driver);

MODULE_AUTHOR("Marc Pignat");
MODULE_DESCRIPTION("National Semiconductor adcxx8sxxx Linux driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
74ba9207	1	// SPDX-License-Identifier: GPL-2.0-or-later
d42139a3 MP	2	/*
	3	* adcxx.c
	4	*
	5	* The adcxx4s is an AD converter family from National Semiconductor (NS).
	6	*
	7	* Copyright (c) 2008 Marc Pignat <marc.pignat@hevs.ch>
	8	*
	9	* The adcxx4s communicates with a host processor via an SPI/Microwire Bus
	10	* interface. This driver supports the whole family of devices with name
	11	* ADC<bb><c>S<sss>, where
	12	* * bb is the resolution in number of bits (8, 10, 12)
	13	* * c is the number of channels (1, 2, 4, 8)
	14	* * sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500 kSPS
	15	* and 101 for 1 MSPS)
	16	*
	17	* Complete datasheets are available at National's website here:
	18	* http://www.national.com/ds/DC/ADC<bb><c>S<sss>.pdf
	19	*
	20	* Handling of 8, 10 and 12 bits converters are the same, the
	21	* unavailable bits are 0 :)
d42139a3 MP	22	*/
	23
	24	#include <linux/init.h>
	25	#include <linux/module.h>
	26	#include <linux/kernel.h>
5a0e3ad6	27	#include <linux/slab.h>
d42139a3 MP	28	#include <linux/device.h>
	29	#include <linux/err.h>
	30	#include <linux/sysfs.h>
	31	#include <linux/hwmon.h>
	32	#include <linux/hwmon-sysfs.h>
	33	#include <linux/mutex.h>
d2a5c10f	34	#include <linux/mod_devicetable.h>
d42139a3 MP	35	#include <linux/spi/spi.h>
	36
	37	#define DRVNAME "adcxx"
	38
	39	struct adcxx {
	40	struct device *hwmon_dev;
	41	struct mutex lock;
	42	u32 channels;
	43	u32 reference; /* in millivolts */
	44	};
	45
	46	/* sysfs hook function */
b0c130fd GR	47	static ssize_t adcxx_show(struct device *dev,
b0c130fd GR	48	struct device_attribute devattr, char buf)
d42139a3 MP	49	{
	50	struct spi_device *spi = to_spi_device(dev);
	51	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
95de3b25	52	struct adcxx *adc = spi_get_drvdata(spi);
5748150e	53	u8 tx_buf[2];
d42139a3 MP	54	u8 rx_buf[2];
d42139a3 MP	55	int status;
5748150e	56	u32 value;
d42139a3 MP	57
	58	if (mutex_lock_interruptible(&adc->lock))
	59	return -ERESTARTSYS;
	60
5748150e JMG	61	if (adc->channels == 1) {
	62	status = spi_read(spi, rx_buf, sizeof(rx_buf));
	63	} else {
	64	tx_buf[0] = attr->index << 3; /* other bits are don't care */
	65	status = spi_write_then_read(spi, tx_buf, sizeof(tx_buf),
	66	rx_buf, sizeof(rx_buf));
	67	}
d42139a3	68	if (status < 0) {
5748150e	69	dev_warn(dev, "SPI synch. transfer failed with status %d\n",
d42139a3 MP	70	status);
	71	goto out;
	72	}
	73
	74	value = (rx_buf[0] << 8) + rx_buf[1];
	75	dev_dbg(dev, "raw value = 0x%x\n", value);
	76
	77	value = value * adc->reference >> 12;
	78	status = sprintf(buf, "%d\n", value);
	79	out:
	80	mutex_unlock(&adc->lock);
	81	return status;
	82	}
	83
b0c130fd GR	84	static ssize_t adcxx_min_show(struct device *dev,
b0c130fd GR	85	struct device_attribute devattr, char buf)
d42139a3 MP	86	{
	87	/* The minimum reference is 0 for this chip family */
	88	return sprintf(buf, "0\n");
	89	}
	90
b0c130fd GR	91	static ssize_t adcxx_max_show(struct device *dev,
b0c130fd GR	92	struct device_attribute devattr, char buf)
d42139a3 MP	93	{
d42139a3 MP	94	struct spi_device *spi = to_spi_device(dev);
95de3b25	95	struct adcxx *adc = spi_get_drvdata(spi);
d42139a3 MP	96	u32 reference;
	97
	98	if (mutex_lock_interruptible(&adc->lock))
	99	return -ERESTARTSYS;
	100
	101	reference = adc->reference;
	102
	103	mutex_unlock(&adc->lock);
	104
	105	return sprintf(buf, "%d\n", reference);
	106	}
	107
b0c130fd GR	108	static ssize_t adcxx_max_store(struct device *dev,
	109	struct device_attribute *devattr,
	110	const char *buf, size_t count)
d42139a3 MP	111	{
d42139a3 MP	112	struct spi_device *spi = to_spi_device(dev);
95de3b25	113	struct adcxx *adc = spi_get_drvdata(spi);
d42139a3 MP	114	unsigned long value;
d42139a3 MP	115
179c4fdb	116	if (kstrtoul(buf, 10, &value))
d42139a3 MP	117	return -EINVAL;
	118
	119	if (mutex_lock_interruptible(&adc->lock))
	120	return -ERESTARTSYS;
	121
	122	adc->reference = value;
	123
	124	mutex_unlock(&adc->lock);
	125
	126	return count;
	127	}
	128
b0c130fd GR	129	static ssize_t adcxx_name_show(struct device *dev,
b0c130fd GR	130	struct device_attribute devattr, char buf)
d42139a3	131	{
cc00e4dd	132	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
d42139a3 MP	133	}
	134
	135	static struct sensor_device_attribute ad_input[] = {
b0c130fd GR	136	SENSOR_ATTR_RO(name, adcxx_name, 0),
	137	SENSOR_ATTR_RO(in_min, adcxx_min, 0),
	138	SENSOR_ATTR_RW(in_max, adcxx_max, 0),
	139	SENSOR_ATTR_RO(in0_input, adcxx, 0),
	140	SENSOR_ATTR_RO(in1_input, adcxx, 1),
	141	SENSOR_ATTR_RO(in2_input, adcxx, 2),
	142	SENSOR_ATTR_RO(in3_input, adcxx, 3),
	143	SENSOR_ATTR_RO(in4_input, adcxx, 4),
	144	SENSOR_ATTR_RO(in5_input, adcxx, 5),
	145	SENSOR_ATTR_RO(in6_input, adcxx, 6),
	146	SENSOR_ATTR_RO(in7_input, adcxx, 7),
d42139a3 MP	147	};
	148
	149	/----------------------------------------------------------------------/
	150
6c931ae1	151	static int adcxx_probe(struct spi_device *spi)
d42139a3	152	{
d2a5c10f	153	int channels = spi_get_device_id(spi)->driver_data;
d42139a3 MP	154	struct adcxx *adc;
	155	int status;
	156	int i;
	157
c60da825	158	adc = devm_kzalloc(&spi->dev, sizeof(*adc), GFP_KERNEL);
d42139a3 MP	159	if (!adc)
	160	return -ENOMEM;
	161
	162	/* set a default value for the reference */
	163	adc->reference = 3300;
	164	adc->channels = channels;
	165	mutex_init(&adc->lock);
	166
	167	mutex_lock(&adc->lock);
	168
95de3b25	169	spi_set_drvdata(spi, adc);
d42139a3 MP	170
	171	for (i = 0; i < 3 + adc->channels; i++) {
	172	status = device_create_file(&spi->dev, &ad_input[i].dev_attr);
	173	if (status) {
	174	dev_err(&spi->dev, "device_create_file failed.\n");
	175	goto out_err;
	176	}
	177	}
	178
	179	adc->hwmon_dev = hwmon_device_register(&spi->dev);
	180	if (IS_ERR(adc->hwmon_dev)) {
	181	dev_err(&spi->dev, "hwmon_device_register failed.\n");
	182	status = PTR_ERR(adc->hwmon_dev);
	183	goto out_err;
	184	}
	185
	186	mutex_unlock(&adc->lock);
	187	return 0;
	188
	189	out_err:
	190	for (i--; i >= 0; i--)
	191	device_remove_file(&spi->dev, &ad_input[i].dev_attr);
	192
d42139a3	193	mutex_unlock(&adc->lock);
d42139a3 MP	194	return status;
	195	}
	196
281dfd0b	197	static int adcxx_remove(struct spi_device *spi)
d42139a3	198	{
95de3b25	199	struct adcxx *adc = spi_get_drvdata(spi);
d42139a3 MP	200	int i;
	201
	202	mutex_lock(&adc->lock);
	203	hwmon_device_unregister(adc->hwmon_dev);
	204	for (i = 0; i < 3 + adc->channels; i++)
	205	device_remove_file(&spi->dev, &ad_input[i].dev_attr);
	206
d42139a3	207	mutex_unlock(&adc->lock);
d42139a3 MP	208
	209	return 0;
	210	}
	211
d2a5c10f AV	212	static const struct spi_device_id adcxx_ids[] = {
	213	{ "adcxx1s", 1 },
	214	{ "adcxx2s", 2 },
	215	{ "adcxx4s", 4 },
	216	{ "adcxx8s", 8 },
	217	{ },
d42139a3	218	};
d2a5c10f	219	MODULE_DEVICE_TABLE(spi, adcxx_ids);
d42139a3	220
d2a5c10f	221	static struct spi_driver adcxx_driver = {
d42139a3	222	.driver = {
d2a5c10f	223	.name = "adcxx",
d42139a3	224	},
d2a5c10f AV	225	.id_table = adcxx_ids,
d2a5c10f AV	226	.probe = adcxx_probe,
9e5e9b7a	227	.remove = adcxx_remove,
d42139a3 MP	228	};
d42139a3 MP	229
91efffe2	230	module_spi_driver(adcxx_driver);
d42139a3 MP	231
	232	MODULE_AUTHOR("Marc Pignat");
	233	MODULE_DESCRIPTION("National Semiconductor adcxx8sxxx Linux driver");
	234	MODULE_LICENSE("GPL");