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-rw-r--r--drivers/iio/pressure/ms5611_spi.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_spi.c b/drivers/iio/pressure/ms5611_spi.c
new file mode 100644
index 000000000..a0a7205c9
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_spi.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MS5611 pressure and temperature sensor driver (SPI bus)
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/mod_devicetable.h>
+
+#include <asm/unaligned.h>
+
+#include "ms5611.h"
+
+static int ms5611_spi_reset(struct ms5611_state *st)
+{
+ u8 cmd = MS5611_RESET;
+
+ return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
+}
+
+static int ms5611_spi_read_prom_word(struct ms5611_state *st, int index,
+ u16 *word)
+{
+ int ret;
+
+ ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));
+ if (ret < 0)
+ return ret;
+
+ *word = ret;
+
+ return 0;
+}
+
+static int ms5611_spi_read_adc(struct ms5611_state *st, s32 *val)
+{
+ int ret;
+ u8 buf[3] = { MS5611_READ_ADC };
+
+ ret = spi_write_then_read(st->client, buf, 1, buf, 3);
+ if (ret < 0)
+ return ret;
+
+ *val = get_unaligned_be24(&buf[0]);
+
+ return 0;
+}
+
+static int ms5611_spi_read_adc_temp_and_pressure(struct ms5611_state *st,
+ s32 *temp, s32 *pressure)
+{
+ int ret;
+ const struct ms5611_osr *osr = st->temp_osr;
+
+ /*
+ * Warning: &osr->cmd MUST be aligned on a word boundary since used as
+ * 2nd argument (void*) of spi_write_then_read.
+ */
+ ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
+ ret = ms5611_spi_read_adc(st, temp);
+ if (ret < 0)
+ return ret;
+
+ osr = st->pressure_osr;
+ ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
+ return ms5611_spi_read_adc(st, pressure);
+}
+
+static int ms5611_spi_probe(struct spi_device *spi)
+{
+ int ret;
+ struct ms5611_state *st;
+ struct iio_dev *indio_dev;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ spi_set_drvdata(spi, indio_dev);
+
+ spi->mode = SPI_MODE_0;
+ spi->max_speed_hz = min(spi->max_speed_hz, 20000000U);
+ spi->bits_per_word = 8;
+ ret = spi_setup(spi);
+ if (ret < 0)
+ return ret;
+
+ st = iio_priv(indio_dev);
+ st->reset = ms5611_spi_reset;
+ st->read_prom_word = ms5611_spi_read_prom_word;
+ st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;
+ st->client = spi;
+
+ return ms5611_probe(indio_dev, &spi->dev, spi_get_device_id(spi)->name,
+ spi_get_device_id(spi)->driver_data);
+}
+
+static void ms5611_spi_remove(struct spi_device *spi)
+{
+ ms5611_remove(spi_get_drvdata(spi));
+}
+
+static const struct of_device_id ms5611_spi_matches[] = {
+ { .compatible = "meas,ms5611" },
+ { .compatible = "meas,ms5607" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ms5611_spi_matches);
+
+static const struct spi_device_id ms5611_id[] = {
+ { "ms5611", MS5611 },
+ { "ms5607", MS5607 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, ms5611_id);
+
+static struct spi_driver ms5611_driver = {
+ .driver = {
+ .name = "ms5611",
+ .of_match_table = ms5611_spi_matches
+ },
+ .id_table = ms5611_id,
+ .probe = ms5611_spi_probe,
+ .remove = ms5611_spi_remove,
+};
+module_spi_driver(ms5611_driver);
+
+MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
+MODULE_DESCRIPTION("MS5611 spi driver");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_MS5611);