diff options
Diffstat (limited to 'drivers/iio/pressure/dlhl60d.c')
-rw-r--r-- | drivers/iio/pressure/dlhl60d.c | 372 |
1 files changed, 372 insertions, 0 deletions
diff --git a/drivers/iio/pressure/dlhl60d.c b/drivers/iio/pressure/dlhl60d.c new file mode 100644 index 000000000..f0b0d198c --- /dev/null +++ b/drivers/iio/pressure/dlhl60d.c @@ -0,0 +1,372 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * All Sensors DLH series low voltage digital pressure sensors + * + * Copyright (c) 2019 AVL DiTEST GmbH + * Tomislav Denis <tomislav.denis@avl.com> + * + * Datasheet: https://www.allsensors.com/cad/DS-0355_Rev_B.PDF + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> +#include <asm/unaligned.h> + +/* Commands */ +#define DLH_START_SINGLE 0xAA + +/* Status bits */ +#define DLH_STATUS_OK 0x40 + +/* DLH data format */ +#define DLH_NUM_READ_BYTES 7 +#define DLH_NUM_DATA_BYTES 3 +#define DLH_NUM_PR_BITS 24 +#define DLH_NUM_TEMP_BITS 24 + +/* DLH timings */ +#define DLH_SINGLE_DUT_MS 5 + +enum dhl_ids { + dlhl60d, + dlhl60g, +}; + +struct dlh_info { + u8 osdig; /* digital offset factor */ + unsigned int fss; /* full scale span (inch H2O) */ +}; + +struct dlh_state { + struct i2c_client *client; + struct dlh_info info; + bool use_interrupt; + struct completion completion; + u8 rx_buf[DLH_NUM_READ_BYTES]; +}; + +static struct dlh_info dlh_info_tbl[] = { + [dlhl60d] = { + .osdig = 2, + .fss = 120, + }, + [dlhl60g] = { + .osdig = 10, + .fss = 60, + }, +}; + + +static int dlh_cmd_start_single(struct dlh_state *st) +{ + int ret; + + ret = i2c_smbus_write_byte(st->client, DLH_START_SINGLE); + if (ret) + dev_err(&st->client->dev, + "%s: I2C write byte failed\n", __func__); + + return ret; +} + +static int dlh_cmd_read_data(struct dlh_state *st) +{ + int ret; + + ret = i2c_master_recv(st->client, st->rx_buf, DLH_NUM_READ_BYTES); + if (ret < 0) { + dev_err(&st->client->dev, + "%s: I2C read block failed\n", __func__); + return ret; + } + + if (st->rx_buf[0] != DLH_STATUS_OK) { + dev_err(&st->client->dev, + "%s: invalid status 0x%02x\n", __func__, st->rx_buf[0]); + return -EBUSY; + } + + return 0; +} + +static int dlh_start_capture_and_read(struct dlh_state *st) +{ + int ret; + + if (st->use_interrupt) + reinit_completion(&st->completion); + + ret = dlh_cmd_start_single(st); + if (ret) + return ret; + + if (st->use_interrupt) { + ret = wait_for_completion_timeout(&st->completion, + msecs_to_jiffies(DLH_SINGLE_DUT_MS)); + if (!ret) { + dev_err(&st->client->dev, + "%s: conversion timed out\n", __func__); + return -ETIMEDOUT; + } + } else { + mdelay(DLH_SINGLE_DUT_MS); + } + + return dlh_cmd_read_data(st); +} + +static int dlh_read_direct(struct dlh_state *st, + unsigned int *pressure, unsigned int *temperature) +{ + int ret; + + ret = dlh_start_capture_and_read(st); + if (ret) + return ret; + + *pressure = get_unaligned_be24(&st->rx_buf[1]); + *temperature = get_unaligned_be24(&st->rx_buf[4]); + + return 0; +} + +static int dlh_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, int *value, + int *value2, long mask) +{ + struct dlh_state *st = iio_priv(indio_dev); + unsigned int pressure, temperature; + int ret; + s64 tmp; + s32 rem; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + + ret = dlh_read_direct(st, &pressure, &temperature); + iio_device_release_direct_mode(indio_dev); + if (ret) + return ret; + + switch (channel->type) { + case IIO_PRESSURE: + *value = pressure; + return IIO_VAL_INT; + + case IIO_TEMP: + *value = temperature; + return IIO_VAL_INT; + + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SCALE: + switch (channel->type) { + case IIO_PRESSURE: + tmp = div_s64(125LL * st->info.fss * 24909 * 100, + 1 << DLH_NUM_PR_BITS); + tmp = div_s64_rem(tmp, 1000000000LL, &rem); + *value = tmp; + *value2 = rem; + return IIO_VAL_INT_PLUS_NANO; + + case IIO_TEMP: + *value = 125 * 1000; + *value2 = DLH_NUM_TEMP_BITS; + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } + case IIO_CHAN_INFO_OFFSET: + switch (channel->type) { + case IIO_PRESSURE: + *value = -125 * st->info.fss * 24909; + *value2 = 100 * st->info.osdig * 100000; + return IIO_VAL_FRACTIONAL; + + case IIO_TEMP: + *value = -40 * 1000; + return IIO_VAL_INT; + + default: + return -EINVAL; + } + } + + return -EINVAL; +} + +static const struct iio_info dlh_info = { + .read_raw = dlh_read_raw, +}; + +static const struct iio_chan_spec dlh_channels[] = { + { + .type = IIO_PRESSURE, + .indexed = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_type = + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .scan_index = 0, + .scan_type = { + .sign = 'u', + .realbits = DLH_NUM_PR_BITS, + .storagebits = 32, + .shift = 8, + .endianness = IIO_BE, + }, + }, { + .type = IIO_TEMP, + .indexed = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_type = + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .scan_index = 1, + .scan_type = { + .sign = 'u', + .realbits = DLH_NUM_TEMP_BITS, + .storagebits = 32, + .shift = 8, + .endianness = IIO_BE, + }, + } +}; + +static irqreturn_t dlh_trigger_handler(int irq, void *private) +{ + struct iio_poll_func *pf = private; + struct iio_dev *indio_dev = pf->indio_dev; + struct dlh_state *st = iio_priv(indio_dev); + int ret; + unsigned int chn, i = 0; + __be32 tmp_buf[2]; + + ret = dlh_start_capture_and_read(st); + if (ret) + goto out; + + for_each_set_bit(chn, indio_dev->active_scan_mask, + indio_dev->masklength) { + memcpy(tmp_buf + i, + &st->rx_buf[1] + chn * DLH_NUM_DATA_BYTES, + DLH_NUM_DATA_BYTES); + i++; + } + + iio_push_to_buffers(indio_dev, tmp_buf); + +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static irqreturn_t dlh_interrupt(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct dlh_state *st = iio_priv(indio_dev); + + complete(&st->completion); + + return IRQ_HANDLED; +}; + +static int dlh_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct dlh_state *st; + struct iio_dev *indio_dev; + int ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) { + dev_err(&client->dev, + "adapter doesn't support required i2c functionality\n"); + return -EOPNOTSUPP; + } + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + if (!indio_dev) { + dev_err(&client->dev, "failed to allocate iio device\n"); + return -ENOMEM; + } + + i2c_set_clientdata(client, indio_dev); + + st = iio_priv(indio_dev); + st->info = dlh_info_tbl[id->driver_data]; + st->client = client; + st->use_interrupt = false; + + indio_dev->name = id->name; + indio_dev->info = &dlh_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = dlh_channels; + indio_dev->num_channels = ARRAY_SIZE(dlh_channels); + + if (client->irq > 0) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + dlh_interrupt, NULL, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + id->name, indio_dev); + if (ret) { + dev_err(&client->dev, "failed to allocate threaded irq"); + return ret; + } + + st->use_interrupt = true; + init_completion(&st->completion); + } + + ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, + NULL, &dlh_trigger_handler, NULL); + if (ret) { + dev_err(&client->dev, "failed to setup iio buffer\n"); + return ret; + } + + ret = devm_iio_device_register(&client->dev, indio_dev); + if (ret) + dev_err(&client->dev, "failed to register iio device\n"); + + return ret; +} + +static const struct of_device_id dlh_of_match[] = { + { .compatible = "asc,dlhl60d" }, + { .compatible = "asc,dlhl60g" }, + {} +}; +MODULE_DEVICE_TABLE(of, dlh_of_match); + +static const struct i2c_device_id dlh_id[] = { + { "dlhl60d", dlhl60d }, + { "dlhl60g", dlhl60g }, + {} +}; +MODULE_DEVICE_TABLE(i2c, dlh_id); + +static struct i2c_driver dlh_driver = { + .driver = { + .name = "dlhl60d", + .of_match_table = dlh_of_match, + }, + .probe = dlh_probe, + .id_table = dlh_id, +}; +module_i2c_driver(dlh_driver); + +MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>"); +MODULE_DESCRIPTION("Driver for All Sensors DLH series pressure sensors"); +MODULE_LICENSE("GPL v2"); |