--- /dev/null
+/**
+ * BMA220 Digital triaxial acceleration sensor driver
+ *
+ * Copyright (c) 2016, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ */
+
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/spi/spi.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 0x80
+#define BMA220_RANGE_MASK 0x03
+#define BMA220_DATA_SHIFT 2
+#define BMA220_SUSPEND_SLEEP 0xFF
+#define BMA220_SUSPEND_WAKE 0x00
+
+#define BMA220_DEVICE_NAME "bma220"
+#define BMA220_SCALE_AVAILABLE "0.623 1.248 2.491 4.983"
+
+#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), \
+}
+
+static IIO_CONST_ATTR(in_accel_scale_available, BMA220_SCALE_AVAILABLE);
+
+static struct attribute *bma220_attributes[] = {
+ &iio_const_attr_in_accel_scale_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group bma220_attribute_group = {
+ .attrs = bma220_attributes,
+};
+
+static const int bma220_scale_table[][4] = {
+ {0, 623000}, {1, 248000}, {2, 491000}, {4, 983000}
+};
+
+struct bma220_data {
+ struct spi_device *spi_device;
+ struct mutex lock;
+ u8 tx_buf[2] ____cacheline_aligned;
+};
+
+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),
+};
+
+static inline int bma220_read_reg(struct spi_device *spi, u8 reg)
+{
+ return spi_w8r8(spi, reg | BMA220_READ_MASK);
+}
+
+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 >> BMA220_DATA_SHIFT, 5);
+ 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 const struct iio_info bma220_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = bma220_read_raw,
+ .write_raw = bma220_write_raw,
+ .attrs = &bma220_attribute_group,
+};
+
+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 < 0)
+ return ret;
+ else if (ret == BMA220_SUSPEND_WAKE)
+ return bma220_read_reg(spi, BMA220_REG_SUSPEND);
+
+ return 0;
+}
+
+static int bma220_deinit(struct spi_device *spi)
+{
+ int ret;
+
+ /* Make sure the chip is powered off */
+ ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);
+ if (ret < 0)
+ return ret;
+ else if (ret == BMA220_SUSPEND_SLEEP)
+ return bma220_read_reg(spi, BMA220_REG_SUSPEND);
+
+ return 0;
+}
+
+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;
+ spi_set_drvdata(spi, indio_dev);
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = &spi->dev;
+ 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);
+
+ ret = bma220_init(data->spi_device);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(&spi->dev, "iio_device_register failed\n");
+ return bma220_deinit(spi);
+ }
+
+ return ret;
+}
+
+static int bma220_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+
+ iio_device_unregister(indio_dev);
+
+ return bma220_deinit(spi);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int bma220_suspend(struct device *dev)
+{
+ struct bma220_data *data =
+ iio_priv(spi_get_drvdata(to_spi_device(dev)));
+
+ /* The chip can be suspended/woken up by a simple register read. */
+ return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
+}
+
+static int bma220_resume(struct device *dev)
+{
+ struct bma220_data *data =
+ iio_priv(spi_get_drvdata(to_spi_device(dev)));
+
+ return bma220_read_reg(data->spi_device, BMA220_REG_SUSPEND);
+}
+
+static SIMPLE_DEV_PM_OPS(bma220_pm_ops, bma220_suspend, bma220_resume);
+
+#define BMA220_PM_OPS (&bma220_pm_ops)
+#else
+#define BMA220_PM_OPS NULL
+#endif
+
+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 = BMA220_PM_OPS,
+ .acpi_match_table = ACPI_PTR(bma220_acpi_id),
+ },
+ .probe = bma220_probe,
+ .remove = bma220_remove,
+ .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");
projects / openwrt / staging / blogic.git / commitdiff