linux/drivers/iio/pressure/abp060mg.c
Marcin Malagowski 9ecca12edd iio: pressure: Add driver for Honeywell ABP family
This patch adds minimal driver for the Honeywell Amplified Basic
Pressure sensors series. Sensors are pretty simple but are
available in many variants:
- psi/mbar/kPa output,
- analog/i2c/spi,
- gage/differential measurement,
- different measure ranges etc.

Refer to datasheets for more details:
http://sensing.honeywell.com/honeywell-sensing-basic-board-mount-pressure-sensors-abp-series-datasheet-323005128-c-en.pdf
http://sensing.honeywell.com/index.php%3Fci_id%3D45841

Driver internals:
- i2c only. measure request is done by the SMBUS QUICK cmd, so if the i2c
  bus doesn't support it, it is required to send a dummy byte to trigger
  measurement,
- since iio sysfs expects kilopascals, mbar-variants are treated as their
  respective kPa-s, hence i2c id-table has doubled entries in one line:
	{ "abp060mg", ABP006KG }, { "abp006kg", ABP006KG },
- psi-variants have prescaled values in config,
- no temperature reads yet.

Work remained:
- optional temperature channel,
- SPI support,
- DT binding.

Changes since v1:
- mutex is now locked in read_raw(),
- corrected error codes,
- fixed coding style issues,
- renamed few defines and functions abp -> abp060mg
(some structs left as they were to keep the sensible meaning).

Signed-off-by: Marcin Malagowski <mrc@bourne.st>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-10-01 15:14:37 +01:00

277 lines
8.3 KiB
C

/*
* Copyright (C) 2016 - Marcin Malagowski <mrc@bourne.st>
*
* 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 <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#define ABP060MG_ERROR_MASK 0xC000
#define ABP060MG_RESP_TIME_MS 40
#define ABP060MG_MIN_COUNTS 1638 /* = 0x0666 (10% of u14) */
#define ABP060MG_MAX_COUNTS 14745 /* = 0x3999 (90% of u14) */
#define ABP060MG_NUM_COUNTS (ABP060MG_MAX_COUNTS - ABP060MG_MIN_COUNTS)
enum abp_variant {
/* gage [kPa] */
ABP006KG, ABP010KG, ABP016KG, ABP025KG, ABP040KG, ABP060KG, ABP100KG,
ABP160KG, ABP250KG, ABP400KG, ABP600KG, ABP001GG,
/* differential [kPa] */
ABP006KD, ABP010KD, ABP016KD, ABP025KD, ABP040KD, ABP060KD, ABP100KD,
ABP160KD, ABP250KD, ABP400KD,
/* gage [psi] */
ABP001PG, ABP005PG, ABP015PG, ABP030PG, ABP060PG, ABP100PG, ABP150PG,
/* differential [psi] */
ABP001PD, ABP005PD, ABP015PD, ABP030PD, ABP060PD,
};
struct abp_config {
int min;
int max;
};
static struct abp_config abp_config[] = {
/* mbar & kPa variants */
[ABP006KG] = { .min = 0, .max = 6000 },
[ABP010KG] = { .min = 0, .max = 10000 },
[ABP016KG] = { .min = 0, .max = 16000 },
[ABP025KG] = { .min = 0, .max = 25000 },
[ABP040KG] = { .min = 0, .max = 40000 },
[ABP060KG] = { .min = 0, .max = 60000 },
[ABP100KG] = { .min = 0, .max = 100000 },
[ABP160KG] = { .min = 0, .max = 160000 },
[ABP250KG] = { .min = 0, .max = 250000 },
[ABP400KG] = { .min = 0, .max = 400000 },
[ABP600KG] = { .min = 0, .max = 600000 },
[ABP001GG] = { .min = 0, .max = 1000000 },
[ABP006KD] = { .min = -6000, .max = 6000 },
[ABP010KD] = { .min = -10000, .max = 10000 },
[ABP016KD] = { .min = -16000, .max = 16000 },
[ABP025KD] = { .min = -25000, .max = 25000 },
[ABP040KD] = { .min = -40000, .max = 40000 },
[ABP060KD] = { .min = -60000, .max = 60000 },
[ABP100KD] = { .min = -100000, .max = 100000 },
[ABP160KD] = { .min = -160000, .max = 160000 },
[ABP250KD] = { .min = -250000, .max = 250000 },
[ABP400KD] = { .min = -400000, .max = 400000 },
/* psi variants (1 psi ~ 6895 Pa) */
[ABP001PG] = { .min = 0, .max = 6985 },
[ABP005PG] = { .min = 0, .max = 34474 },
[ABP015PG] = { .min = 0, .max = 103421 },
[ABP030PG] = { .min = 0, .max = 206843 },
[ABP060PG] = { .min = 0, .max = 413686 },
[ABP100PG] = { .min = 0, .max = 689476 },
[ABP150PG] = { .min = 0, .max = 1034214 },
[ABP001PD] = { .min = -6895, .max = 6895 },
[ABP005PD] = { .min = -34474, .max = 34474 },
[ABP015PD] = { .min = -103421, .max = 103421 },
[ABP030PD] = { .min = -206843, .max = 206843 },
[ABP060PD] = { .min = -413686, .max = 413686 },
};
struct abp_state {
struct i2c_client *client;
struct mutex lock;
/*
* bus-dependent MEASURE_REQUEST length.
* If no SMBUS_QUICK support, need to send dummy byte
*/
int mreq_len;
/* model-dependent values (calculated on probe) */
int scale;
int offset;
};
static const struct iio_chan_spec abp060mg_channels[] = {
{
.type = IIO_PRESSURE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE),
},
};
static int abp060mg_get_measurement(struct abp_state *state, int *val)
{
struct i2c_client *client = state->client;
__be16 buf[2];
u16 pressure;
int ret;
buf[0] = 0;
ret = i2c_master_send(client, (u8 *)&buf, state->mreq_len);
if (ret < 0)
return ret;
msleep_interruptible(ABP060MG_RESP_TIME_MS);
ret = i2c_master_recv(client, (u8 *)&buf, sizeof(buf));
if (ret < 0)
return ret;
pressure = be16_to_cpu(buf[0]);
if (pressure & ABP060MG_ERROR_MASK)
return -EIO;
if (pressure < ABP060MG_MIN_COUNTS || pressure > ABP060MG_MAX_COUNTS)
return -EIO;
*val = pressure;
return IIO_VAL_INT;
}
static int abp060mg_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val,
int *val2, long mask)
{
struct abp_state *state = iio_priv(indio_dev);
int ret;
mutex_lock(&state->lock);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = abp060mg_get_measurement(state, val);
break;
case IIO_CHAN_INFO_OFFSET:
*val = state->offset;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_SCALE:
*val = state->scale;
*val2 = ABP060MG_NUM_COUNTS * 1000; /* to kPa */
ret = IIO_VAL_FRACTIONAL;
break;
default:
ret = -EINVAL;
break;
}
mutex_unlock(&state->lock);
return ret;
}
static const struct iio_info abp060mg_info = {
.driver_module = THIS_MODULE,
.read_raw = abp060mg_read_raw,
};
static void abp060mg_init_device(struct iio_dev *indio_dev, unsigned long id)
{
struct abp_state *state = iio_priv(indio_dev);
struct abp_config *cfg = &abp_config[id];
state->scale = cfg->max - cfg->min;
state->offset = -ABP060MG_MIN_COUNTS;
if (cfg->min < 0) /* differential */
state->offset -= ABP060MG_NUM_COUNTS >> 1;
}
static int abp060mg_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct iio_dev *indio_dev;
struct abp_state *state;
unsigned long cfg_id = id->driver_data;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*state));
if (!indio_dev)
return -ENOMEM;
state = iio_priv(indio_dev);
i2c_set_clientdata(client, state);
state->client = client;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_QUICK))
state->mreq_len = 1;
abp060mg_init_device(indio_dev, cfg_id);
indio_dev->dev.parent = &client->dev;
indio_dev->name = dev_name(&client->dev);
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &abp060mg_info;
indio_dev->channels = abp060mg_channels;
indio_dev->num_channels = ARRAY_SIZE(abp060mg_channels);
mutex_init(&state->lock);
return devm_iio_device_register(&client->dev, indio_dev);
}
static const struct i2c_device_id abp060mg_id_table[] = {
/* mbar & kPa variants (abp060m [60 mbar] == abp006k [6 kPa]) */
/* gage: */
{ "abp060mg", ABP006KG }, { "abp006kg", ABP006KG },
{ "abp100mg", ABP010KG }, { "abp010kg", ABP010KG },
{ "abp160mg", ABP016KG }, { "abp016kg", ABP016KG },
{ "abp250mg", ABP025KG }, { "abp025kg", ABP025KG },
{ "abp400mg", ABP040KG }, { "abp040kg", ABP040KG },
{ "abp600mg", ABP060KG }, { "abp060kg", ABP060KG },
{ "abp001bg", ABP100KG }, { "abp100kg", ABP100KG },
{ "abp1_6bg", ABP160KG }, { "abp160kg", ABP160KG },
{ "abp2_5bg", ABP250KG }, { "abp250kg", ABP250KG },
{ "abp004bg", ABP400KG }, { "abp400kg", ABP400KG },
{ "abp006bg", ABP600KG }, { "abp600kg", ABP600KG },
{ "abp010bg", ABP001GG }, { "abp001gg", ABP001GG },
/* differential: */
{ "abp060md", ABP006KD }, { "abp006kd", ABP006KD },
{ "abp100md", ABP010KD }, { "abp010kd", ABP010KD },
{ "abp160md", ABP016KD }, { "abp016kd", ABP016KD },
{ "abp250md", ABP025KD }, { "abp025kd", ABP025KD },
{ "abp400md", ABP040KD }, { "abp040kd", ABP040KD },
{ "abp600md", ABP060KD }, { "abp060kd", ABP060KD },
{ "abp001bd", ABP100KD }, { "abp100kd", ABP100KD },
{ "abp1_6bd", ABP160KD }, { "abp160kd", ABP160KD },
{ "abp2_5bd", ABP250KD }, { "abp250kd", ABP250KD },
{ "abp004bd", ABP400KD }, { "abp400kd", ABP400KD },
/* psi variants */
/* gage: */
{ "abp001pg", ABP001PG },
{ "abp005pg", ABP005PG },
{ "abp015pg", ABP015PG },
{ "abp030pg", ABP030PG },
{ "abp060pg", ABP060PG },
{ "abp100pg", ABP100PG },
{ "abp150pg", ABP150PG },
/* differential: */
{ "abp001pd", ABP001PD },
{ "abp005pd", ABP005PD },
{ "abp015pd", ABP015PD },
{ "abp030pd", ABP030PD },
{ "abp060pd", ABP060PD },
{ /* empty */ },
};
MODULE_DEVICE_TABLE(i2c, abp060mg_id_table);
static struct i2c_driver abp060mg_driver = {
.driver = {
.name = "abp060mg",
},
.probe = abp060mg_probe,
.id_table = abp060mg_id_table,
};
module_i2c_driver(abp060mg_driver);
MODULE_AUTHOR("Marcin Malagowski <mrc@bourne.st>");
MODULE_DESCRIPTION("Honeywell ABP pressure sensor driver");
MODULE_LICENSE("GPL");