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-rw-r--r--drivers/iio/accel/bma220_spi.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/iio/accel/bma220_spi.c b/drivers/iio/accel/bma220_spi.c
new file mode 100644
index 000000000..fcbd695e4
--- /dev/null
+++ b/drivers/iio/accel/bma220_spi.c
@@ -0,0 +1,331 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * BMA220 Digital triaxial acceleration sensor driver
+ *
+ * Copyright (c) 2016,2020 Intel Corporation.
+ */
+
+#include <linux/bits.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define BMA220_REG_ID 0x00
+#define BMA220_REG_ACCEL_X 0x02
+#define BMA220_REG_ACCEL_Y 0x03
+#define BMA220_REG_ACCEL_Z 0x04
+#define BMA220_REG_RANGE 0x11
+#define BMA220_REG_SUSPEND 0x18
+
+#define BMA220_CHIP_ID 0xDD
+#define BMA220_READ_MASK BIT(7)
+#define BMA220_RANGE_MASK GENMASK(1, 0)
+#define BMA220_SUSPEND_SLEEP 0xFF
+#define BMA220_SUSPEND_WAKE 0x00
+
+#define BMA220_DEVICE_NAME "bma220"
+
+#define BMA220_ACCEL_CHANNEL(index, reg, axis) { \
+ .type = IIO_ACCEL, \
+ .address = reg, \
+ .modified = 1, \
+ .channel2 = IIO_MOD_##axis, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 6, \
+ .storagebits = 8, \
+ .shift = 2, \
+ .endianness = IIO_CPU, \
+ }, \
+}
+
+enum bma220_axis {
+ AXIS_X,
+ AXIS_Y,
+ AXIS_Z,
+};
+
+static const int bma220_scale_table[][2] = {
+ {0, 623000}, {1, 248000}, {2, 491000}, {4, 983000},
+};
+
+struct bma220_data {
+ struct spi_device *spi_device;
+ struct mutex lock;
+ struct {
+ s8 chans[3];
+ /* Ensure timestamp is naturally aligned. */
+ s64 timestamp __aligned(8);
+ } scan;
+ u8 tx_buf[2] __aligned(IIO_DMA_MINALIGN);
+};
+
+static const struct iio_chan_spec bma220_channels[] = {
+ BMA220_ACCEL_CHANNEL(0, BMA220_REG_ACCEL_X, X),
+ BMA220_ACCEL_CHANNEL(1, BMA220_REG_ACCEL_Y, Y),
+ BMA220_ACCEL_CHANNEL(2, BMA220_REG_ACCEL_Z, Z),
+ IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
+{
+ return spi_w8r8(spi, reg | BMA220_READ_MASK);
+}
+
+static const unsigned long bma220_accel_scan_masks[] = {
+ BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
+ 0
+};
+
+static irqreturn_t bma220_trigger_handler(int irq, void *p)
+{
+ int ret;
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct bma220_data *data = iio_priv(indio_dev);
+ struct spi_device *spi = data->spi_device;
+
+ mutex_lock(&data->lock);
+ data->tx_buf[0] = BMA220_REG_ACCEL_X | BMA220_READ_MASK;
+ ret = spi_write_then_read(spi, data->tx_buf, 1, &data->scan.chans,
+ ARRAY_SIZE(bma220_channels) - 1);
+ if (ret < 0)
+ goto err;
+
+ iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+ pf->timestamp);
+err:
+ mutex_unlock(&data->lock);
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static int bma220_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ u8 range_idx;
+ struct bma220_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = bma220_read_reg(data->spi_device, chan->address);
+ if (ret < 0)
+ return -EINVAL;
+ *val = sign_extend32(ret >> chan->scan_type.shift,
+ chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ ret = bma220_read_reg(data->spi_device, BMA220_REG_RANGE);
+ if (ret < 0)
+ return ret;
+ range_idx = ret & BMA220_RANGE_MASK;
+ *val = bma220_scale_table[range_idx][0];
+ *val2 = bma220_scale_table[range_idx][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ return -EINVAL;
+}
+
+static int bma220_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ int i;
+ int ret;
+ int index = -1;
+ struct bma220_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ for (i = 0; i < ARRAY_SIZE(bma220_scale_table); i++)
+ if (val == bma220_scale_table[i][0] &&
+ val2 == bma220_scale_table[i][1]) {
+ index = i;
+ break;
+ }
+ if (index < 0)
+ return -EINVAL;
+
+ mutex_lock(&data->lock);
+ data->tx_buf[0] = BMA220_REG_RANGE;
+ data->tx_buf[1] = index;
+ ret = spi_write(data->spi_device, data->tx_buf,
+ sizeof(data->tx_buf));
+ if (ret < 0)
+ dev_err(&data->spi_device->dev,
+ "failed to set measurement range\n");
+ mutex_unlock(&data->lock);
+
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int bma220_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ *vals = (int *)bma220_scale_table;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ *length = ARRAY_SIZE(bma220_scale_table) * 2;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info bma220_info = {
+ .read_raw = bma220_read_raw,
+ .write_raw = bma220_write_raw,
+ .read_avail = bma220_read_avail,
+};
+
+static int bma220_init(struct spi_device *spi)
+{
+ int ret;
+
+ ret = bma220_read_reg(spi, BMA220_REG_ID);
+ if (ret != BMA220_CHIP_ID)
+ return -ENODEV;
+
+ /* Make sure the chip is powered on */
+ ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+ if (ret == BMA220_SUSPEND_WAKE)
+ ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+ if (ret < 0)
+ return ret;
+ if (ret == BMA220_SUSPEND_WAKE)
+ return -EBUSY;
+
+ return 0;
+}
+
+static int bma220_power(struct spi_device *spi, bool up)
+{
+ int i, ret;
+
+ /**
+ * The chip can be suspended/woken up by a simple register read.
+ * So, we need up to 2 register reads of the suspend register
+ * to make sure that the device is in the desired state.
+ */
+ for (i = 0; i < 2; i++) {
+ ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+ if (ret < 0)
+ return ret;
+
+ if (up && ret == BMA220_SUSPEND_SLEEP)
+ return 0;
+
+ if (!up && ret == BMA220_SUSPEND_WAKE)
+ return 0;
+ }
+
+ return -EBUSY;
+}
+
+static void bma220_deinit(void *spi)
+{
+ bma220_power(spi, false);
+}
+
+static int bma220_probe(struct spi_device *spi)
+{
+ int ret;
+ struct iio_dev *indio_dev;
+ struct bma220_data *data;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
+ if (!indio_dev) {
+ dev_err(&spi->dev, "iio allocation failed!\n");
+ return -ENOMEM;
+ }
+
+ data = iio_priv(indio_dev);
+ data->spi_device = spi;
+ mutex_init(&data->lock);
+
+ indio_dev->info = &bma220_info;
+ indio_dev->name = BMA220_DEVICE_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = bma220_channels;
+ indio_dev->num_channels = ARRAY_SIZE(bma220_channels);
+ indio_dev->available_scan_masks = bma220_accel_scan_masks;
+
+ ret = bma220_init(data->spi_device);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(&spi->dev, bma220_deinit, spi);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+ iio_pollfunc_store_time,
+ bma220_trigger_handler, NULL);
+ if (ret < 0) {
+ dev_err(&spi->dev, "iio triggered buffer setup failed\n");
+ return ret;
+ }
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static int bma220_suspend(struct device *dev)
+{
+ struct spi_device *spi = to_spi_device(dev);
+
+ return bma220_power(spi, false);
+}
+
+static int bma220_resume(struct device *dev)
+{
+ struct spi_device *spi = to_spi_device(dev);
+
+ return bma220_power(spi, true);
+}
+static DEFINE_SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
+
+static const struct spi_device_id bma220_spi_id[] = {
+ {"bma220", 0},
+ {}
+};
+
+static const struct acpi_device_id bma220_acpi_id[] = {
+ {"BMA0220", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, bma220_spi_id);
+
+static struct spi_driver bma220_driver = {
+ .driver = {
+ .name = "bma220_spi",
+ .pm = pm_sleep_ptr(&bma220_pm_ops),
+ .acpi_match_table = bma220_acpi_id,
+ },
+ .probe = bma220_probe,
+ .id_table = bma220_spi_id,
+};
+module_spi_driver(bma220_driver);
+
+MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
+MODULE_DESCRIPTION("BMA220 acceleration sensor driver");
+MODULE_LICENSE("GPL v2");