[linux-block.git] / drivers / hwmon / max1111.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * max1111.c - +2.7V, Low-Power, Multichannel, Serial 8-bit ADCs
 *
 * Based on arch/arm/mach-pxa/corgi_ssp.c
 *
 * Copyright (C) 2004-2005 Richard Purdie
 *
 * Copyright (C) 2008 Marvell International Ltd.
 *	Eric Miao <eric.miao@marvell.com>
 */

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

enum chips { max1110, max1111, max1112, max1113 };

#define MAX1111_TX_BUF_SIZE	1
#define MAX1111_RX_BUF_SIZE	2

/* MAX1111 Commands */
#define MAX1111_CTRL_PD0      (1u << 0)
#define MAX1111_CTRL_PD1      (1u << 1)
#define MAX1111_CTRL_SGL      (1u << 2)
#define MAX1111_CTRL_UNI      (1u << 3)
#define MAX1110_CTRL_SEL_SH   (4)
#define MAX1111_CTRL_SEL_SH   (5)	/* NOTE: bit 4 is ignored */
#define MAX1111_CTRL_STR      (1u << 7)

struct max1111_data {
	struct spi_device	*spi;
	struct device		*hwmon_dev;
	struct spi_message	msg;
	struct spi_transfer	xfer[2];
	uint8_t tx_buf[MAX1111_TX_BUF_SIZE];
	uint8_t rx_buf[MAX1111_RX_BUF_SIZE];
	struct mutex		drvdata_lock;
	/* protect msg, xfer and buffers from multiple access */
	int			sel_sh;
	int			lsb;
};

static int max1111_read(struct device *dev, int channel)
{
	struct max1111_data *data = dev_get_drvdata(dev);
	uint8_t v1, v2;
	int err;

	/* writing to drvdata struct is not thread safe, wait on mutex */
	mutex_lock(&data->drvdata_lock);

	data->tx_buf[0] = (channel << data->sel_sh) |
		MAX1111_CTRL_PD0 | MAX1111_CTRL_PD1 |
		MAX1111_CTRL_SGL | MAX1111_CTRL_UNI | MAX1111_CTRL_STR;

	err = spi_sync(data->spi, &data->msg);
	if (err < 0) {
		dev_err(dev, "spi_sync failed with %d\n", err);
		mutex_unlock(&data->drvdata_lock);
		return err;
	}

	v1 = data->rx_buf[0];
	v2 = data->rx_buf[1];

	mutex_unlock(&data->drvdata_lock);

	if ((v1 & 0xc0) || (v2 & 0x3f))
		return -EINVAL;

	return (v1 << 2) | (v2 >> 6);
}

#ifdef CONFIG_SHARPSL_PM
static struct max1111_data *the_max1111;

int max1111_read_channel(int channel)
{
	if (!the_max1111 || !the_max1111->spi)
		return -ENODEV;

	return max1111_read(&the_max1111->spi->dev, channel);
}
EXPORT_SYMBOL(max1111_read_channel);
#endif

/*
 * NOTE: SPI devices do not have a default 'name' attribute, which is
 * likely to be used by hwmon applications to distinguish between
 * different devices, explicitly add a name attribute here.
 */
static ssize_t name_show(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
}

static ssize_t show_adc(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	struct max1111_data *data = dev_get_drvdata(dev);
	int channel = to_sensor_dev_attr(attr)->index;
	int ret;

	ret = max1111_read(dev, channel);
	if (ret < 0)
		return ret;

	/*
	 * Assume the reference voltage to be 2.048V or 4.096V, with an 8-bit
	 * sample. The LSB weight is 8mV or 16mV depending on the chip type.
	 */
	return sprintf(buf, "%d\n", ret * data->lsb);
}

#define MAX1111_ADC_ATTR(_id)		\
	SENSOR_DEVICE_ATTR(in##_id##_input, S_IRUGO, show_adc, NULL, _id)

static DEVICE_ATTR_RO(name);
static MAX1111_ADC_ATTR(0);
static MAX1111_ADC_ATTR(1);
static MAX1111_ADC_ATTR(2);
static MAX1111_ADC_ATTR(3);
static MAX1111_ADC_ATTR(4);
static MAX1111_ADC_ATTR(5);
static MAX1111_ADC_ATTR(6);
static MAX1111_ADC_ATTR(7);

static struct attribute *max1111_attributes[] = {
	&dev_attr_name.attr,
	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group max1111_attr_group = {
	.attrs	= max1111_attributes,
};

static struct attribute *max1110_attributes[] = {
	&sensor_dev_attr_in4_input.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,
	&sensor_dev_attr_in7_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group max1110_attr_group = {
	.attrs	= max1110_attributes,
};

static int setup_transfer(struct max1111_data *data)
{
	struct spi_message *m;
	struct spi_transfer *x;

	m = &data->msg;
	x = &data->xfer[0];

	spi_message_init(m);

	x->tx_buf = &data->tx_buf[0];
	x->len = MAX1111_TX_BUF_SIZE;
	spi_message_add_tail(x, m);

	x++;
	x->rx_buf = &data->rx_buf[0];
	x->len = MAX1111_RX_BUF_SIZE;
	spi_message_add_tail(x, m);

	return 0;
}

static int max1111_probe(struct spi_device *spi)
{
	enum chips chip = spi_get_device_id(spi)->driver_data;
	struct max1111_data *data;
	int err;

	spi->bits_per_word = 8;
	spi->mode = SPI_MODE_0;
	err = spi_setup(spi);
	if (err < 0)
		return err;

	data = devm_kzalloc(&spi->dev, sizeof(struct max1111_data), GFP_KERNEL);
	if (data == NULL)
		return -ENOMEM;

	switch (chip) {
	case max1110:
		data->lsb = 8;
		data->sel_sh = MAX1110_CTRL_SEL_SH;
		break;
	case max1111:
		data->lsb = 8;
		data->sel_sh = MAX1111_CTRL_SEL_SH;
		break;
	case max1112:
		data->lsb = 16;
		data->sel_sh = MAX1110_CTRL_SEL_SH;
		break;
	case max1113:
		data->lsb = 16;
		data->sel_sh = MAX1111_CTRL_SEL_SH;
		break;
	}
	err = setup_transfer(data);
	if (err)
		return err;

	mutex_init(&data->drvdata_lock);

	data->spi = spi;
	spi_set_drvdata(spi, data);

	err = sysfs_create_group(&spi->dev.kobj, &max1111_attr_group);
	if (err) {
		dev_err(&spi->dev, "failed to create attribute group\n");
		return err;
	}
	if (chip == max1110 || chip == max1112) {
		err = sysfs_create_group(&spi->dev.kobj, &max1110_attr_group);
		if (err) {
			dev_err(&spi->dev,
				"failed to create extended attribute group\n");
			goto err_remove;
		}
	}

	data->hwmon_dev = hwmon_device_register(&spi->dev);
	if (IS_ERR(data->hwmon_dev)) {
		dev_err(&spi->dev, "failed to create hwmon device\n");
		err = PTR_ERR(data->hwmon_dev);
		goto err_remove;
	}

#ifdef CONFIG_SHARPSL_PM
	the_max1111 = data;
#endif
	return 0;

err_remove:
	sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group);
	sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group);
	return err;
}

static void max1111_remove(struct spi_device *spi)
{
	struct max1111_data *data = spi_get_drvdata(spi);

#ifdef CONFIG_SHARPSL_PM
	the_max1111 = NULL;
#endif
	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group);
	sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group);
	mutex_destroy(&data->drvdata_lock);
}

static const struct spi_device_id max1111_ids[] = {
	{ "max1110", max1110 },
	{ "max1111", max1111 },
	{ "max1112", max1112 },
	{ "max1113", max1113 },
	{ },
};
MODULE_DEVICE_TABLE(spi, max1111_ids);

static struct spi_driver max1111_driver = {
	.driver		= {
		.name	= "max1111",
	},
	.id_table	= max1111_ids,
	.probe		= max1111_probe,
	.remove		= max1111_remove,
};

module_spi_driver(max1111_driver);

MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("MAX1110/MAX1111/MAX1112/MAX1113 ADC Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
1d0ea069	1	// SPDX-License-Identifier: GPL-2.0-only
55b951e7 EM	2	/*
	3	* max1111.c - +2.7V, Low-Power, Multichannel, Serial 8-bit ADCs
	4	*
	5	* Based on arch/arm/mach-pxa/corgi_ssp.c
	6	*
	7	* Copyright (C) 2004-2005 Richard Purdie
	8	*
	9	* Copyright (C) 2008 Marvell International Ltd.
91c8eabe	10	* Eric Miao <eric.miao@marvell.com>
55b951e7 EM	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/kernel.h>
	15	#include <linux/init.h>
	16	#include <linux/err.h>
	17	#include <linux/hwmon.h>
	18	#include <linux/hwmon-sysfs.h>
	19	#include <linux/spi/spi.h>
5a0e3ad6	20	#include <linux/slab.h>
55b951e7	21
9224c38a GR	22	enum chips { max1110, max1111, max1112, max1113 };
9224c38a GR	23
55b951e7 EM	24	#define MAX1111_TX_BUF_SIZE 1
	25	#define MAX1111_RX_BUF_SIZE 2
	26
	27	/* MAX1111 Commands */
	28	#define MAX1111_CTRL_PD0 (1u << 0)
	29	#define MAX1111_CTRL_PD1 (1u << 1)
	30	#define MAX1111_CTRL_SGL (1u << 2)
	31	#define MAX1111_CTRL_UNI (1u << 3)
9224c38a	32	#define MAX1110_CTRL_SEL_SH (4)
55b951e7 EM	33	#define MAX1111_CTRL_SEL_SH (5) /* NOTE: bit 4 is ignored */
	34	#define MAX1111_CTRL_STR (1u << 7)
	35
	36	struct max1111_data {
	37	struct spi_device *spi;
	38	struct device *hwmon_dev;
	39	struct spi_message msg;
	40	struct spi_transfer xfer[2];
d737c09c JD	41	uint8_t tx_buf[MAX1111_TX_BUF_SIZE];
d737c09c JD	42	uint8_t rx_buf[MAX1111_RX_BUF_SIZE];
d3f684f2 PH	43	struct mutex drvdata_lock;
d3f684f2 PH	44	/* protect msg, xfer and buffers from multiple access */
9224c38a GR	45	int sel_sh;
9224c38a GR	46	int lsb;
55b951e7 EM	47	};
	48
	49	static int max1111_read(struct device *dev, int channel)
	50	{
	51	struct max1111_data *data = dev_get_drvdata(dev);
	52	uint8_t v1, v2;
	53	int err;
	54
d3f684f2 PH	55	/* writing to drvdata struct is not thread safe, wait on mutex */
	56	mutex_lock(&data->drvdata_lock);
	57
9224c38a	58	data->tx_buf[0] = (channel << data->sel_sh) \|
55b951e7 EM	59	MAX1111_CTRL_PD0 \| MAX1111_CTRL_PD1 \|
	60	MAX1111_CTRL_SGL \| MAX1111_CTRL_UNI \| MAX1111_CTRL_STR;
	61
	62	err = spi_sync(data->spi, &data->msg);
	63	if (err < 0) {
	64	dev_err(dev, "spi_sync failed with %d\n", err);
d3f684f2	65	mutex_unlock(&data->drvdata_lock);
55b951e7 EM	66	return err;
	67	}
	68
	69	v1 = data->rx_buf[0];
	70	v2 = data->rx_buf[1];
	71
d3f684f2 PH	72	mutex_unlock(&data->drvdata_lock);
d3f684f2 PH	73
55b951e7 EM	74	if ((v1 & 0xc0) \|\| (v2 & 0x3f))
	75	return -EINVAL;
	76
	77	return (v1 << 2) \| (v2 >> 6);
	78	}
	79
f16177c2 EM	80	#ifdef CONFIG_SHARPSL_PM
	81	static struct max1111_data *the_max1111;
	82
	83	int max1111_read_channel(int channel)
	84	{
3c2e2266 GR	85	if (!the_max1111 \|\| !the_max1111->spi)
	86	return -ENODEV;
	87
f16177c2 EM	88	return max1111_read(&the_max1111->spi->dev, channel);
	89	}
	90	EXPORT_SYMBOL(max1111_read_channel);
	91	#endif
	92
55b951e7 EM	93	/*
	94	* NOTE: SPI devices do not have a default 'name' attribute, which is
	95	* likely to be used by hwmon applications to distinguish between
	96	* different devices, explicitly add a name attribute here.
	97	*/
17c45c4d	98	static ssize_t name_show(struct device *dev,
55b951e7 EM	99	struct device_attribute attr, char buf)
55b951e7 EM	100	{
9224c38a	101	return sprintf(buf, "%s\n", to_spi_device(dev)->modalias);
55b951e7 EM	102	}
	103
	104	static ssize_t show_adc(struct device *dev,
	105	struct device_attribute attr, char buf)
	106	{
9224c38a	107	struct max1111_data *data = dev_get_drvdata(dev);
55b951e7 EM	108	int channel = to_sensor_dev_attr(attr)->index;
	109	int ret;
	110
	111	ret = max1111_read(dev, channel);
	112	if (ret < 0)
	113	return ret;
	114
51683ee8	115	/*
9224c38a GR	116	* Assume the reference voltage to be 2.048V or 4.096V, with an 8-bit
9224c38a GR	117	* sample. The LSB weight is 8mV or 16mV depending on the chip type.
012f3b91	118	*/
9224c38a	119	return sprintf(buf, "%d\n", ret * data->lsb);
55b951e7 EM	120	}
	121
	122	#define MAX1111_ADC_ATTR(_id) \
012f3b91	123	SENSOR_DEVICE_ATTR(in##_id##_input, S_IRUGO, show_adc, NULL, _id)
55b951e7	124
17c45c4d	125	static DEVICE_ATTR_RO(name);
55b951e7 EM	126	static MAX1111_ADC_ATTR(0);
	127	static MAX1111_ADC_ATTR(1);
	128	static MAX1111_ADC_ATTR(2);
	129	static MAX1111_ADC_ATTR(3);
9224c38a GR	130	static MAX1111_ADC_ATTR(4);
	131	static MAX1111_ADC_ATTR(5);
	132	static MAX1111_ADC_ATTR(6);
	133	static MAX1111_ADC_ATTR(7);
55b951e7 EM	134
	135	static struct attribute *max1111_attributes[] = {
	136	&dev_attr_name.attr,
012f3b91 EM	137	&sensor_dev_attr_in0_input.dev_attr.attr,
	138	&sensor_dev_attr_in1_input.dev_attr.attr,
	139	&sensor_dev_attr_in2_input.dev_attr.attr,
	140	&sensor_dev_attr_in3_input.dev_attr.attr,
55b951e7 EM	141	NULL,
	142	};
	143
	144	static const struct attribute_group max1111_attr_group = {
	145	.attrs = max1111_attributes,
	146	};
	147
9224c38a GR	148	static struct attribute *max1110_attributes[] = {
	149	&sensor_dev_attr_in4_input.dev_attr.attr,
	150	&sensor_dev_attr_in5_input.dev_attr.attr,
	151	&sensor_dev_attr_in6_input.dev_attr.attr,
	152	&sensor_dev_attr_in7_input.dev_attr.attr,
	153	NULL,
	154	};
	155
	156	static const struct attribute_group max1110_attr_group = {
	157	.attrs = max1110_attributes,
	158	};
	159
6c931ae1	160	static int setup_transfer(struct max1111_data *data)
55b951e7 EM	161	{
	162	struct spi_message *m;
	163	struct spi_transfer *x;
	164
55b951e7 EM	165	m = &data->msg;
	166	x = &data->xfer[0];
	167
	168	spi_message_init(m);
	169
	170	x->tx_buf = &data->tx_buf[0];
d737c09c	171	x->len = MAX1111_TX_BUF_SIZE;
55b951e7 EM	172	spi_message_add_tail(x, m);
	173
	174	x++;
	175	x->rx_buf = &data->rx_buf[0];
d737c09c	176	x->len = MAX1111_RX_BUF_SIZE;
55b951e7 EM	177	spi_message_add_tail(x, m);
	178
	179	return 0;
	180	}
	181
6c931ae1	182	static int max1111_probe(struct spi_device *spi)
55b951e7	183	{
9224c38a	184	enum chips chip = spi_get_device_id(spi)->driver_data;
55b951e7 EM	185	struct max1111_data *data;
	186	int err;
	187
	188	spi->bits_per_word = 8;
	189	spi->mode = SPI_MODE_0;
	190	err = spi_setup(spi);
	191	if (err < 0)
	192	return err;
	193
661f020f	194	data = devm_kzalloc(&spi->dev, sizeof(struct max1111_data), GFP_KERNEL);
611cd8ae	195	if (data == NULL)
55b951e7	196	return -ENOMEM;
55b951e7	197
9224c38a GR	198	switch (chip) {
	199	case max1110:
	200	data->lsb = 8;
	201	data->sel_sh = MAX1110_CTRL_SEL_SH;
	202	break;
	203	case max1111:
	204	data->lsb = 8;
	205	data->sel_sh = MAX1111_CTRL_SEL_SH;
	206	break;
	207	case max1112:
	208	data->lsb = 16;
	209	data->sel_sh = MAX1110_CTRL_SEL_SH;
	210	break;
	211	case max1113:
	212	data->lsb = 16;
	213	data->sel_sh = MAX1111_CTRL_SEL_SH;
	214	break;
	215	}
55b951e7 EM	216	err = setup_transfer(data);
55b951e7 EM	217	if (err)
661f020f	218	return err;
55b951e7	219
d3f684f2 PH	220	mutex_init(&data->drvdata_lock);
d3f684f2 PH	221
55b951e7 EM	222	data->spi = spi;
	223	spi_set_drvdata(spi, data);
	224
	225	err = sysfs_create_group(&spi->dev.kobj, &max1111_attr_group);
	226	if (err) {
	227	dev_err(&spi->dev, "failed to create attribute group\n");
661f020f	228	return err;
55b951e7	229	}
9224c38a GR	230	if (chip == max1110 \|\| chip == max1112) {
	231	err = sysfs_create_group(&spi->dev.kobj, &max1110_attr_group);
	232	if (err) {
	233	dev_err(&spi->dev,
	234	"failed to create extended attribute group\n");
	235	goto err_remove;
	236	}
	237	}
55b951e7 EM	238
	239	data->hwmon_dev = hwmon_device_register(&spi->dev);
	240	if (IS_ERR(data->hwmon_dev)) {
	241	dev_err(&spi->dev, "failed to create hwmon device\n");
	242	err = PTR_ERR(data->hwmon_dev);
	243	goto err_remove;
	244	}
	245
f16177c2 EM	246	#ifdef CONFIG_SHARPSL_PM
	247	the_max1111 = data;
	248	#endif
55b951e7 EM	249	return 0;
	250
	251	err_remove:
9224c38a	252	sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group);
55b951e7	253	sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group);
55b951e7 EM	254	return err;
	255	}
	256
a0386bba	257	static void max1111_remove(struct spi_device *spi)
55b951e7 EM	258	{
	259	struct max1111_data *data = spi_get_drvdata(spi);
	260
3c2e2266 GR	261	#ifdef CONFIG_SHARPSL_PM
	262	the_max1111 = NULL;
	263	#endif
55b951e7	264	hwmon_device_unregister(data->hwmon_dev);
9224c38a	265	sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group);
55b951e7	266	sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group);
d3f684f2	267	mutex_destroy(&data->drvdata_lock);
55b951e7 EM	268	}
55b951e7 EM	269
9224c38a GR	270	static const struct spi_device_id max1111_ids[] = {
	271	{ "max1110", max1110 },
	272	{ "max1111", max1111 },
	273	{ "max1112", max1112 },
	274	{ "max1113", max1113 },
	275	{ },
	276	};
	277	MODULE_DEVICE_TABLE(spi, max1111_ids);
	278
55b951e7 EM	279	static struct spi_driver max1111_driver = {
	280	.driver = {
	281	.name = "max1111",
55b951e7	282	},
9224c38a	283	.id_table = max1111_ids,
55b951e7	284	.probe = max1111_probe,
9e5e9b7a	285	.remove = max1111_remove,
55b951e7 EM	286	};
55b951e7 EM	287
91efffe2	288	module_spi_driver(max1111_driver);
55b951e7 EM	289
55b951e7 EM	290	MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>");
9224c38a	291	MODULE_DESCRIPTION("MAX1110/MAX1111/MAX1112/MAX1113 ADC Driver");
55b951e7	292	MODULE_LICENSE("GPL");