#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 <linux/unaligned.h>
#define DLH_START_SINGLE 0xAA
#define DLH_STATUS_OK 0x40
#define DLH_NUM_READ_BYTES 7
#define DLH_NUM_DATA_BYTES 3
#define DLH_NUM_PR_BITS 24
#define DLH_NUM_TEMP_BITS 24
#define DLH_SINGLE_DUT_MS 5
struct dlh_info {
const char *name;
u8 osdig;
unsigned int fss;
};
struct dlh_state {
struct i2c_client *client;
const struct dlh_info *info;
bool use_interrupt;
struct completion completion;
u8 rx_buf[DLH_NUM_READ_BYTES];
};
static const struct dlh_info dlhl60d_info = {
.name = "dlhl60d",
.osdig = 2,
.fss = 120,
};
static const struct dlh_info dlhl60g_info = {
.name = "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:
if (!iio_device_claim_direct(indio_dev))
return -EBUSY;
ret = dlh_read_direct(st, &pressure, &temperature);
iio_device_release_direct(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;
iio_for_each_active_channel(indio_dev, chn) {
memcpy(&tmp_buf[i++],
&st->rx_buf[1] + chn * DLH_NUM_DATA_BYTES,
DLH_NUM_DATA_BYTES);
}
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)
{
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)
return -ENOMEM;
i2c_set_clientdata(client, indio_dev);
st = iio_priv(indio_dev);
st->info = i2c_get_match_data(client);
st->client = client;
st->use_interrupt = false;
indio_dev->name = st->info->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_irq(&client->dev, client->irq, dlh_interrupt,
IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
st->info->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", .data = &dlhl60d_info },
{ .compatible = "asc,dlhl60g", .data = &dlhl60g_info },
{ }
};
MODULE_DEVICE_TABLE(of, dlh_of_match);
static const struct i2c_device_id dlh_id[] = {
{ "dlhl60d", (kernel_ulong_t)&dlhl60d_info },
{ "dlhl60g", (kernel_ulong_t)&dlhl60g_info },
{ }
};
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");
