diff options
Diffstat (limited to 'drivers/iio/accel/kxsd9.c')
| -rw-r--r-- | drivers/iio/accel/kxsd9.c | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c new file mode 100644 index 000000000..ba99649fe --- /dev/null +++ b/drivers/iio/accel/kxsd9.c @@ -0,0 +1,516 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * kxsd9.c simple support for the Kionix KXSD9 3D + * accelerometer. + * + * Copyright (c) 2008-2009 Jonathan Cameron <jic23@kernel.org> + * + * The i2c interface is very similar, so shouldn't be a problem once + * I have a suitable wire made up. + * + * TODO: Support the motion detector + */ + +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/sysfs.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/regulator/consumer.h> +#include <linux/pm_runtime.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/buffer.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/iio/trigger_consumer.h> + +#include "kxsd9.h" + +#define KXSD9_REG_X 0x00 +#define KXSD9_REG_Y 0x02 +#define KXSD9_REG_Z 0x04 +#define KXSD9_REG_AUX 0x06 +#define KXSD9_REG_RESET 0x0a +#define KXSD9_REG_CTRL_C 0x0c + +#define KXSD9_CTRL_C_FS_MASK 0x03 +#define KXSD9_CTRL_C_FS_8G 0x00 +#define KXSD9_CTRL_C_FS_6G 0x01 +#define KXSD9_CTRL_C_FS_4G 0x02 +#define KXSD9_CTRL_C_FS_2G 0x03 +#define KXSD9_CTRL_C_MOT_LAT BIT(3) +#define KXSD9_CTRL_C_MOT_LEV BIT(4) +#define KXSD9_CTRL_C_LP_MASK 0xe0 +#define KXSD9_CTRL_C_LP_NONE 0x00 +#define KXSD9_CTRL_C_LP_2000HZC BIT(5) +#define KXSD9_CTRL_C_LP_2000HZB BIT(6) +#define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6)) +#define KXSD9_CTRL_C_LP_1000HZ BIT(7) +#define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5)) +#define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6)) +#define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5)) + +#define KXSD9_REG_CTRL_B 0x0d + +#define KXSD9_CTRL_B_CLK_HLD BIT(7) +#define KXSD9_CTRL_B_ENABLE BIT(6) +#define KXSD9_CTRL_B_ST BIT(5) /* Self-test */ + +#define KXSD9_REG_CTRL_A 0x0e + +/** + * struct kxsd9_state - device related storage + * @dev: pointer to the parent device + * @map: regmap to the device + * @orientation: mounting matrix, flipped axis etc + * @regs: regulators for this device, VDD and IOVDD + * @scale: the current scaling setting + */ +struct kxsd9_state { + struct device *dev; + struct regmap *map; + struct iio_mount_matrix orientation; + struct regulator_bulk_data regs[2]; + u8 scale; +}; + +#define KXSD9_SCALE_2G "0.011978" +#define KXSD9_SCALE_4G "0.023927" +#define KXSD9_SCALE_6G "0.035934" +#define KXSD9_SCALE_8G "0.047853" + +/* reverse order */ +static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 }; + +#define KXSD9_ZERO_G_OFFSET -2048 + +/* + * Regulator names + */ +static const char kxsd9_reg_vdd[] = "vdd"; +static const char kxsd9_reg_iovdd[] = "iovdd"; + +static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro) +{ + int ret, i; + struct kxsd9_state *st = iio_priv(indio_dev); + bool foundit = false; + + for (i = 0; i < 4; i++) + if (micro == kxsd9_micro_scales[i]) { + foundit = true; + break; + } + if (!foundit) + return -EINVAL; + + ret = regmap_update_bits(st->map, + KXSD9_REG_CTRL_C, + KXSD9_CTRL_C_FS_MASK, + i); + if (ret < 0) + goto error_ret; + + /* Cached scale when the sensor is powered down */ + st->scale = i; + +error_ret: + return ret; +} + +static IIO_CONST_ATTR(accel_scale_available, + KXSD9_SCALE_2G " " + KXSD9_SCALE_4G " " + KXSD9_SCALE_6G " " + KXSD9_SCALE_8G); + +static struct attribute *kxsd9_attributes[] = { + &iio_const_attr_accel_scale_available.dev_attr.attr, + NULL, +}; + +static int kxsd9_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long mask) +{ + int ret = -EINVAL; + struct kxsd9_state *st = iio_priv(indio_dev); + + pm_runtime_get_sync(st->dev); + + if (mask == IIO_CHAN_INFO_SCALE) { + /* Check no integer component */ + if (val) + return -EINVAL; + ret = kxsd9_write_scale(indio_dev, val2); + } + + pm_runtime_mark_last_busy(st->dev); + pm_runtime_put_autosuspend(st->dev); + + return ret; +} + +static int kxsd9_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + int ret = -EINVAL; + struct kxsd9_state *st = iio_priv(indio_dev); + unsigned int regval; + __be16 raw_val; + u16 nval; + + pm_runtime_get_sync(st->dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = regmap_bulk_read(st->map, chan->address, &raw_val, + sizeof(raw_val)); + if (ret) + goto error_ret; + nval = be16_to_cpu(raw_val); + /* Only 12 bits are valid */ + nval >>= 4; + *val = nval; + ret = IIO_VAL_INT; + break; + case IIO_CHAN_INFO_OFFSET: + /* This has a bias of -2048 */ + *val = KXSD9_ZERO_G_OFFSET; + ret = IIO_VAL_INT; + break; + case IIO_CHAN_INFO_SCALE: + ret = regmap_read(st->map, + KXSD9_REG_CTRL_C, + ®val); + if (ret < 0) + goto error_ret; + *val = 0; + *val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK]; + ret = IIO_VAL_INT_PLUS_MICRO; + break; + } + +error_ret: + pm_runtime_mark_last_busy(st->dev); + pm_runtime_put_autosuspend(st->dev); + + return ret; +}; + +static irqreturn_t kxsd9_trigger_handler(int irq, void *p) +{ + const struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct kxsd9_state *st = iio_priv(indio_dev); + /* + * Ensure correct positioning and alignment of timestamp. + * No need to zero initialize as all elements written. + */ + struct { + __be16 chan[4]; + s64 ts __aligned(8); + } hw_values; + int ret; + + ret = regmap_bulk_read(st->map, + KXSD9_REG_X, + hw_values.chan, + sizeof(hw_values.chan)); + if (ret) { + dev_err(st->dev, "error reading data: %d\n", ret); + goto out; + } + + iio_push_to_buffers_with_timestamp(indio_dev, + &hw_values, + iio_get_time_ns(indio_dev)); +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int kxsd9_buffer_preenable(struct iio_dev *indio_dev) +{ + struct kxsd9_state *st = iio_priv(indio_dev); + + pm_runtime_get_sync(st->dev); + + return 0; +} + +static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct kxsd9_state *st = iio_priv(indio_dev); + + pm_runtime_mark_last_busy(st->dev); + pm_runtime_put_autosuspend(st->dev); + + return 0; +} + +static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = { + .preenable = kxsd9_buffer_preenable, + .postdisable = kxsd9_buffer_postdisable, +}; + +static const struct iio_mount_matrix * +kxsd9_get_mount_matrix(const struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct kxsd9_state *st = iio_priv(indio_dev); + + return &st->orientation; +} + +static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = { + IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix), + { }, +}; + +#define KXSD9_ACCEL_CHAN(axis, index) \ + { \ + .type = IIO_ACCEL, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .ext_info = kxsd9_ext_info, \ + .address = KXSD9_REG_##axis, \ + .scan_index = index, \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + .shift = 4, \ + .endianness = IIO_BE, \ + }, \ + } + +static const struct iio_chan_spec kxsd9_channels[] = { + KXSD9_ACCEL_CHAN(X, 0), + KXSD9_ACCEL_CHAN(Y, 1), + KXSD9_ACCEL_CHAN(Z, 2), + { + .type = IIO_VOLTAGE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .indexed = 1, + .address = KXSD9_REG_AUX, + .scan_index = 3, + .scan_type = { + .sign = 'u', + .realbits = 12, + .storagebits = 16, + .shift = 4, + .endianness = IIO_BE, + }, + }, + IIO_CHAN_SOFT_TIMESTAMP(4), +}; + +static const struct attribute_group kxsd9_attribute_group = { + .attrs = kxsd9_attributes, +}; + +static int kxsd9_power_up(struct kxsd9_state *st) +{ + int ret; + + /* Enable the regulators */ + ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs); + if (ret) { + dev_err(st->dev, "Cannot enable regulators\n"); + return ret; + } + + /* Power up */ + ret = regmap_write(st->map, + KXSD9_REG_CTRL_B, + KXSD9_CTRL_B_ENABLE); + if (ret) + return ret; + + /* + * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g, + * latched wakeup + */ + ret = regmap_write(st->map, + KXSD9_REG_CTRL_C, + KXSD9_CTRL_C_LP_1000HZ | + KXSD9_CTRL_C_MOT_LEV | + KXSD9_CTRL_C_MOT_LAT | + st->scale); + if (ret) + return ret; + + /* + * Power-up time depends on the LPF setting, but typ 15.9 ms, let's + * set 20 ms to allow for some slack. + */ + msleep(20); + + return 0; +}; + +static int kxsd9_power_down(struct kxsd9_state *st) +{ + int ret; + + /* + * Set into low power mode - since there may be more users of the + * regulators this is the first step of the power saving: it will + * make sure we conserve power even if there are others users on the + * regulators. + */ + ret = regmap_update_bits(st->map, + KXSD9_REG_CTRL_B, + KXSD9_CTRL_B_ENABLE, + 0); + if (ret) + return ret; + + /* Disable the regulators */ + ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs); + if (ret) { + dev_err(st->dev, "Cannot disable regulators\n"); + return ret; + } + + return 0; +} + +static const struct iio_info kxsd9_info = { + .read_raw = &kxsd9_read_raw, + .write_raw = &kxsd9_write_raw, + .attrs = &kxsd9_attribute_group, +}; + +/* Four channels apart from timestamp, scan mask = 0x0f */ +static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 }; + +int kxsd9_common_probe(struct device *dev, + struct regmap *map, + const char *name) +{ + struct iio_dev *indio_dev; + struct kxsd9_state *st; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + st->dev = dev; + st->map = map; + + indio_dev->channels = kxsd9_channels; + indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels); + indio_dev->name = name; + indio_dev->info = &kxsd9_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->available_scan_masks = kxsd9_scan_masks; + + /* Read the mounting matrix, if present */ + ret = iio_read_mount_matrix(dev, &st->orientation); + if (ret) + return ret; + + /* Fetch and turn on regulators */ + st->regs[0].supply = kxsd9_reg_vdd; + st->regs[1].supply = kxsd9_reg_iovdd; + ret = devm_regulator_bulk_get(dev, + ARRAY_SIZE(st->regs), + st->regs); + if (ret) { + dev_err(dev, "Cannot get regulators\n"); + return ret; + } + /* Default scaling */ + st->scale = KXSD9_CTRL_C_FS_2G; + + kxsd9_power_up(st); + + ret = iio_triggered_buffer_setup(indio_dev, + iio_pollfunc_store_time, + kxsd9_trigger_handler, + &kxsd9_buffer_setup_ops); + if (ret) { + dev_err(dev, "triggered buffer setup failed\n"); + goto err_power_down; + } + + ret = iio_device_register(indio_dev); + if (ret) + goto err_cleanup_buffer; + + dev_set_drvdata(dev, indio_dev); + + /* Enable runtime PM */ + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + /* + * Set autosuspend to two orders of magnitude larger than the + * start-up time. 20ms start-up time means 2000ms autosuspend, + * i.e. 2 seconds. + */ + pm_runtime_set_autosuspend_delay(dev, 2000); + pm_runtime_use_autosuspend(dev); + pm_runtime_put(dev); + + return 0; + +err_cleanup_buffer: + iio_triggered_buffer_cleanup(indio_dev); +err_power_down: + kxsd9_power_down(st); + + return ret; +} +EXPORT_SYMBOL_NS(kxsd9_common_probe, IIO_KXSD9); + +void kxsd9_common_remove(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct kxsd9_state *st = iio_priv(indio_dev); + + iio_triggered_buffer_cleanup(indio_dev); + iio_device_unregister(indio_dev); + pm_runtime_get_sync(dev); + pm_runtime_put_noidle(dev); + pm_runtime_disable(dev); + kxsd9_power_down(st); +} +EXPORT_SYMBOL_NS(kxsd9_common_remove, IIO_KXSD9); + +static int kxsd9_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct kxsd9_state *st = iio_priv(indio_dev); + + return kxsd9_power_down(st); +} + +static int kxsd9_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct kxsd9_state *st = iio_priv(indio_dev); + + return kxsd9_power_up(st); +} + +EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend, + kxsd9_runtime_resume, NULL, IIO_KXSD9); + +MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); +MODULE_DESCRIPTION("Kionix KXSD9 driver"); +MODULE_LICENSE("GPL v2"); |