drivers/iio/pressure/mprls0025pa_spi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * MPRLS0025PA - Honeywell MicroPressure MPR series SPI sensor driver
   4  *
   5  * Copyright (c) 2024 Petre Rodan <petre.rodan@subdimension.ro>
   6  *
   7  * Data sheet:
   8  *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
   9  */
  10
  11 #include <linux/device.h>
  12 #include <linux/errno.h>
  13 #include <linux/mod_devicetable.h>
  14 #include <linux/module.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/stddef.h>
  17 #include <linux/types.h>
  18
  19 #include "mprls0025pa.h"
  20
  21 struct mpr_spi_buf {
  22         u8 tx[MPR_MEASUREMENT_RD_SIZE] __aligned(IIO_DMA_MINALIGN);
  23 };
  24
  25 static int mpr_spi_init(struct device *dev)
  26 {
  27         struct spi_device *spi = to_spi_device(dev);
  28         struct mpr_spi_buf *buf;
  29
  30         buf = devm_kzalloc(dev, sizeof(*buf), GFP_KERNEL);
  31         if (!buf)
  32                 return -ENOMEM;
  33
  34         spi_set_drvdata(spi, buf);
  35
  36         return 0;
  37 }
  38
  39 static int mpr_spi_xfer(struct mpr_data *data, const u8 cmd, const u8 pkt_len)
  40 {
  41         struct spi_device *spi = to_spi_device(data->dev);
  42         struct mpr_spi_buf *buf = spi_get_drvdata(spi);
  43         struct spi_transfer xfer;
  44
  45         if (pkt_len > MPR_MEASUREMENT_RD_SIZE)
  46                 return -EOVERFLOW;
  47
  48         buf->tx[0] = cmd;
  49         xfer.tx_buf = buf->tx;
  50         xfer.rx_buf = data->buffer;
  51         xfer.len = pkt_len;
  52
  53         return spi_sync_transfer(spi, &xfer, 1);
  54 }
  55
  56 static const struct mpr_ops mpr_spi_ops = {
  57         .init = mpr_spi_init,
  58         .read = mpr_spi_xfer,
  59         .write = mpr_spi_xfer,
  60 };
  61
  62 static int mpr_spi_probe(struct spi_device *spi)
  63 {
  64         return mpr_common_probe(&spi->dev, &mpr_spi_ops, spi->irq);
  65 }
  66
  67 static const struct of_device_id mpr_spi_match[] = {
  68         { .compatible = "honeywell,mprls0025pa" },
  69         {}
  70 };
  71 MODULE_DEVICE_TABLE(of, mpr_spi_match);
  72
  73 static const struct spi_device_id mpr_spi_id[] = {
  74         { "mprls0025pa" },
  75         {}
  76 };
  77 MODULE_DEVICE_TABLE(spi, mpr_spi_id);
  78
  79 static struct spi_driver mpr_spi_driver = {
  80         .driver = {
  81                 .name = "mprls0025pa",
  82                 .of_match_table = mpr_spi_match,
  83         },
  84         .probe = mpr_spi_probe,
  85         .id_table = mpr_spi_id,
  86 };
  87 module_spi_driver(mpr_spi_driver);
  88
  89 MODULE_AUTHOR("Petre Rodan <petre.rodan@subdimension.ro>");
  90 MODULE_DESCRIPTION("Honeywell MPR pressure sensor spi driver");
  91 MODULE_LICENSE("GPL");
  92 MODULE_IMPORT_NS("IIO_HONEYWELL_MPRLS0025PA");