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-rw-r--r--drivers/iio/accel/adxl367_spi.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/iio/accel/adxl367_spi.c b/drivers/iio/accel/adxl367_spi.c
new file mode 100644
index 000000000000..26dfc821ebbe
--- /dev/null
+++ b/drivers/iio/accel/adxl367_spi.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Analog Devices, Inc.
+ * Author: Cosmin Tanislav <cosmin.tanislav@analog.com>
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "adxl367.h"
+
+#define ADXL367_SPI_WRITE_COMMAND 0x0A
+#define ADXL367_SPI_READ_COMMAND 0x0B
+#define ADXL367_SPI_FIFO_COMMAND 0x0D
+
+struct adxl367_spi_state {
+ struct spi_device *spi;
+
+ struct spi_message reg_write_msg;
+ struct spi_transfer reg_write_xfer[2];
+
+ struct spi_message reg_read_msg;
+ struct spi_transfer reg_read_xfer[2];
+
+ struct spi_message fifo_msg;
+ struct spi_transfer fifo_xfer[2];
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ u8 reg_write_tx_buf[1] ____cacheline_aligned;
+ u8 reg_read_tx_buf[2];
+ u8 fifo_tx_buf[1];
+};
+
+static int adxl367_read_fifo(void *context, __be16 *fifo_buf,
+ unsigned int fifo_entries)
+{
+ struct adxl367_spi_state *st = context;
+
+ st->fifo_xfer[1].rx_buf = fifo_buf;
+ st->fifo_xfer[1].len = fifo_entries * sizeof(*fifo_buf);
+
+ return spi_sync(st->spi, &st->fifo_msg);
+}
+
+static int adxl367_read(void *context, const void *reg_buf, size_t reg_size,
+ void *val_buf, size_t val_size)
+{
+ struct adxl367_spi_state *st = context;
+ u8 reg = ((const u8 *)reg_buf)[0];
+
+ st->reg_read_tx_buf[1] = reg;
+ st->reg_read_xfer[1].rx_buf = val_buf;
+ st->reg_read_xfer[1].len = val_size;
+
+ return spi_sync(st->spi, &st->reg_read_msg);
+}
+
+static int adxl367_write(void *context, const void *val_buf, size_t val_size)
+{
+ struct adxl367_spi_state *st = context;
+
+ st->reg_write_xfer[1].tx_buf = val_buf;
+ st->reg_write_xfer[1].len = val_size;
+
+ return spi_sync(st->spi, &st->reg_write_msg);
+}
+
+static struct regmap_bus adxl367_spi_regmap_bus = {
+ .read = adxl367_read,
+ .write = adxl367_write,
+};
+
+static const struct regmap_config adxl367_spi_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+
+static const struct adxl367_ops adxl367_spi_ops = {
+ .read_fifo = adxl367_read_fifo,
+};
+
+static int adxl367_spi_probe(struct spi_device *spi)
+{
+ struct adxl367_spi_state *st;
+ struct regmap *regmap;
+
+ st = devm_kzalloc(&spi->dev, sizeof(*st), GFP_KERNEL);
+ if (!st)
+ return -ENOMEM;
+
+ st->spi = spi;
+
+ /*
+ * Xfer: [XFR1] [ XFR2 ]
+ * Master: 0x0A ADDR DATA0 DATA1 ... DATAN
+ * Slave: .... ..........................
+ */
+ st->reg_write_tx_buf[0] = ADXL367_SPI_WRITE_COMMAND;
+ st->reg_write_xfer[0].tx_buf = st->reg_write_tx_buf;
+ st->reg_write_xfer[0].len = sizeof(st->reg_write_tx_buf);
+ spi_message_init_with_transfers(&st->reg_write_msg,
+ st->reg_write_xfer, 2);
+
+ /*
+ * Xfer: [ XFR1 ] [ XFR2 ]
+ * Master: 0x0B ADDR .....................
+ * Slave: ......... DATA0 DATA1 ... DATAN
+ */
+ st->reg_read_tx_buf[0] = ADXL367_SPI_READ_COMMAND;
+ st->reg_read_xfer[0].tx_buf = st->reg_read_tx_buf;
+ st->reg_read_xfer[0].len = sizeof(st->reg_read_tx_buf);
+ spi_message_init_with_transfers(&st->reg_read_msg,
+ st->reg_read_xfer, 2);
+
+ /*
+ * Xfer: [XFR1] [ XFR2 ]
+ * Master: 0x0D .....................
+ * Slave: .... DATA0 DATA1 ... DATAN
+ */
+ st->fifo_tx_buf[0] = ADXL367_SPI_FIFO_COMMAND;
+ st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
+ st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
+ spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer, 2);
+
+ regmap = devm_regmap_init(&spi->dev, &adxl367_spi_regmap_bus, st,
+ &adxl367_spi_regmap_config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ return adxl367_probe(&spi->dev, &adxl367_spi_ops, st, regmap, spi->irq);
+}
+
+static const struct spi_device_id adxl367_spi_id[] = {
+ { "adxl367", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(spi, adxl367_spi_id);
+
+static const struct of_device_id adxl367_of_match[] = {
+ { .compatible = "adi,adxl367" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, adxl367_of_match);
+
+static struct spi_driver adxl367_spi_driver = {
+ .driver = {
+ .name = "adxl367_spi",
+ .of_match_table = adxl367_of_match,
+ },
+ .probe = adxl367_spi_probe,
+ .id_table = adxl367_spi_id,
+};
+
+module_spi_driver(adxl367_spi_driver);
+
+MODULE_IMPORT_NS(IIO_ADXL367);
+MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>");
+MODULE_DESCRIPTION("Analog Devices ADXL367 3-axis accelerometer SPI driver");
+MODULE_LICENSE("GPL");