--- /dev/null
+// 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: http://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] ____cacheline_aligned;
+};
+
+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_be32(&st->rx_buf[1]) >> 8;
+ *temperature = get_unaligned_be32(&st->rx_buf[3]) &
+ GENMASK(DLH_NUM_TEMP_BITS - 1, 0);
+
+ 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->dev.parent = &client->dev;
+ indio_dev->dev.of_node = client->dev.of_node;
+ 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");
projects / thirdparty / linux.git / commitdiff
