--- /dev/null
- .scan_index = voltage0,
+ /**
+ * Copyright (c) 2011 Jonathan Cameron
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * A reference industrial I/O driver to illustrate the functionality available.
+ *
+ * There are numerous real drivers to illustrate the finer points.
+ * The purpose of this driver is to provide a driver with far more comments
+ * and explanatory notes than any 'real' driver would have.
+ * Anyone starting out writing an IIO driver should first make sure they
+ * understand all of this driver except those bits specifically marked
+ * as being present to allow us to 'fake' the presence of hardware.
+ */
+ #include <linux/kernel.h>
+ #include <linux/slab.h>
+ #include <linux/module.h>
+
+ #include <linux/iio/iio.h>
+ #include <linux/iio/sysfs.h>
+ #include <linux/iio/events.h>
+ #include <linux/iio/buffer.h>
+ #include "iio_simple_dummy.h"
+
+ /*
+ * A few elements needed to fake a bus for this driver
+ * Note instances parameter controls how many of these
+ * dummy devices are registered.
+ */
+ static unsigned instances = 1;
+ module_param(instances, uint, 0);
+
+ /* Pointer array used to fake bus elements */
+ static struct iio_dev **iio_dummy_devs;
+
+ /* Fake a name for the part number, usually obtained from the id table */
+ static const char *iio_dummy_part_number = "iio_dummy_part_no";
+
+ /**
+ * struct iio_dummy_accel_calibscale - realworld to register mapping
+ * @val: first value in read_raw - here integer part.
+ * @val2: second value in read_raw etc - here micro part.
+ * @regval: register value - magic device specific numbers.
+ */
+ struct iio_dummy_accel_calibscale {
+ int val;
+ int val2;
+ int regval; /* what would be written to hardware */
+ };
+
+ static const struct iio_dummy_accel_calibscale dummy_scales[] = {
+ { 0, 100, 0x8 }, /* 0.000100 */
+ { 0, 133, 0x7 }, /* 0.000133 */
+ { 733, 13, 0x9 }, /* 733.000013 */
+ };
+
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+
+ /*
+ * simple event - triggered when value rises above
+ * a threshold
+ */
+ static const struct iio_event_spec iio_dummy_event = {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE),
+ };
+
+ /*
+ * simple step detect event - triggered when a step is detected
+ */
+ static const struct iio_event_spec step_detect_event = {
+ .type = IIO_EV_TYPE_CHANGE,
+ .dir = IIO_EV_DIR_NONE,
+ .mask_separate = BIT(IIO_EV_INFO_ENABLE),
+ };
+
+ /*
+ * simple transition event - triggered when the reported running confidence
+ * value rises above a threshold value
+ */
+ static const struct iio_event_spec iio_running_event = {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_RISING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE),
+ };
+
+ /*
+ * simple transition event - triggered when the reported walking confidence
+ * value falls under a threshold value
+ */
+ static const struct iio_event_spec iio_walking_event = {
+ .type = IIO_EV_TYPE_THRESH,
+ .dir = IIO_EV_DIR_FALLING,
+ .mask_separate = BIT(IIO_EV_INFO_VALUE) | BIT(IIO_EV_INFO_ENABLE),
+ };
+ #endif
+
+ /*
+ * iio_dummy_channels - Description of available channels
+ *
+ * This array of structures tells the IIO core about what the device
+ * actually provides for a given channel.
+ */
+ static const struct iio_chan_spec iio_dummy_channels[] = {
+ /* indexed ADC channel in_voltage0_raw etc */
+ {
+ .type = IIO_VOLTAGE,
+ /* Channel has a numeric index of 0 */
+ .indexed = 1,
+ .channel = 0,
+ /* What other information is available? */
+ .info_mask_separate =
+ /*
+ * in_voltage0_raw
+ * Raw (unscaled no bias removal etc) measurement
+ * from the device.
+ */
+ BIT(IIO_CHAN_INFO_RAW) |
+ /*
+ * in_voltage0_offset
+ * Offset for userspace to apply prior to scale
+ * when converting to standard units (microvolts)
+ */
+ BIT(IIO_CHAN_INFO_OFFSET) |
+ /*
+ * in_voltage0_scale
+ * Multipler for userspace to apply post offset
+ * when converting to standard units (microvolts)
+ */
+ BIT(IIO_CHAN_INFO_SCALE),
+ /*
+ * sampling_frequency
+ * The frequency in Hz at which the channels are sampled
+ */
+ .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ /* The ordering of elements in the buffer via an enum */
- .scan_index = diffvoltage1m2,
++ .scan_index = DUMMY_INDEX_VOLTAGE_0,
+ .scan_type = { /* Description of storage in buffer */
+ .sign = 'u', /* unsigned */
+ .realbits = 13, /* 13 bits */
+ .storagebits = 16, /* 16 bits used for storage */
+ .shift = 0, /* zero shift */
+ },
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ .event_spec = &iio_dummy_event,
+ .num_event_specs = 1,
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ },
+ /* Differential ADC channel in_voltage1-voltage2_raw etc*/
+ {
+ .type = IIO_VOLTAGE,
+ .differential = 1,
+ /*
+ * Indexing for differential channels uses channel
+ * for the positive part, channel2 for the negative.
+ */
+ .indexed = 1,
+ .channel = 1,
+ .channel2 = 2,
+ /*
+ * in_voltage1-voltage2_raw
+ * Raw (unscaled no bias removal etc) measurement
+ * from the device.
+ */
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ /*
+ * in_voltage-voltage_scale
+ * Shared version of scale - shared by differential
+ * input channels of type IIO_VOLTAGE.
+ */
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ /*
+ * sampling_frequency
+ * The frequency in Hz at which the channels are sampled
+ */
- .scan_index = diffvoltage3m4,
++ .scan_index = DUMMY_INDEX_DIFFVOLTAGE_1M2,
+ .scan_type = { /* Description of storage in buffer */
+ .sign = 's', /* signed */
+ .realbits = 12, /* 12 bits */
+ .storagebits = 16, /* 16 bits used for storage */
+ .shift = 0, /* zero shift */
+ },
+ },
+ /* Differential ADC channel in_voltage3-voltage4_raw etc*/
+ {
+ .type = IIO_VOLTAGE,
+ .differential = 1,
+ .indexed = 1,
+ .channel = 3,
+ .channel2 = 4,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
- .scan_index = accelx,
++ .scan_index = DUMMY_INDEX_DIFFVOLTAGE_3M4,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 11,
+ .storagebits = 16,
+ .shift = 0,
+ },
+ },
+ /*
+ * 'modified' (i.e. axis specified) acceleration channel
+ * in_accel_z_raw
+ */
+ {
+ .type = IIO_ACCEL,
+ .modified = 1,
+ /* Channel 2 is use for modifiers */
+ .channel2 = IIO_MOD_X,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ /*
+ * Internal bias and gain correction values. Applied
+ * by the hardware or driver prior to userspace
+ * seeing the readings. Typically part of hardware
+ * calibration.
+ */
+ BIT(IIO_CHAN_INFO_CALIBSCALE) |
+ BIT(IIO_CHAN_INFO_CALIBBIAS),
+ .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ),
- /* all differential adc channels ->
- * 0.000001344 */
++ .scan_index = DUMMY_INDEX_ACCELX,
+ .scan_type = { /* Description of storage in buffer */
+ .sign = 's', /* signed */
+ .realbits = 16, /* 16 bits */
+ .storagebits = 16, /* 16 bits used for storage */
+ .shift = 0, /* zero shift */
+ },
+ },
+ /*
+ * Convenience macro for timestamps. 4 is the index in
+ * the buffer.
+ */
+ IIO_CHAN_SOFT_TIMESTAMP(4),
+ /* DAC channel out_voltage0_raw */
+ {
+ .type = IIO_VOLTAGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .scan_index = -1, /* No buffer support */
+ .output = 1,
+ .indexed = 1,
+ .channel = 0,
+ },
+ {
+ .type = IIO_STEPS,
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_ENABLE) |
+ BIT(IIO_CHAN_INFO_CALIBHEIGHT),
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ .scan_index = -1, /* No buffer support */
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ .event_spec = &step_detect_event,
+ .num_event_specs = 1,
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ },
+ {
+ .type = IIO_ACTIVITY,
+ .modified = 1,
+ .channel2 = IIO_MOD_RUNNING,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ .scan_index = -1, /* No buffer support */
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ .event_spec = &iio_running_event,
+ .num_event_specs = 1,
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ },
+ {
+ .type = IIO_ACTIVITY,
+ .modified = 1,
+ .channel2 = IIO_MOD_WALKING,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ .scan_index = -1, /* No buffer support */
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ .event_spec = &iio_walking_event,
+ .num_event_specs = 1,
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ },
+ };
+
+ /**
+ * iio_dummy_read_raw() - data read function.
+ * @indio_dev: the struct iio_dev associated with this device instance
+ * @chan: the channel whose data is to be read
+ * @val: first element of returned value (typically INT)
+ * @val2: second element of returned value (typically MICRO)
+ * @mask: what we actually want to read as per the info_mask_*
+ * in iio_chan_spec.
+ */
+ static int iio_dummy_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+ {
+ struct iio_dummy_state *st = iio_priv(indio_dev);
+ int ret = -EINVAL;
+
+ mutex_lock(&st->lock);
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW: /* magic value - channel value read */
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ if (chan->output) {
+ /* Set integer part to cached value */
+ *val = st->dac_val;
+ ret = IIO_VAL_INT;
+ } else if (chan->differential) {
+ if (chan->channel == 1)
+ *val = st->differential_adc_val[0];
+ else
+ *val = st->differential_adc_val[1];
+ ret = IIO_VAL_INT;
+ } else {
+ *val = st->single_ended_adc_val;
+ ret = IIO_VAL_INT;
+ }
+ break;
+ case IIO_ACCEL:
+ *val = st->accel_val;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ break;
+ }
+ break;
+ case IIO_CHAN_INFO_PROCESSED:
+ switch (chan->type) {
+ case IIO_STEPS:
+ *val = st->steps;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_ACTIVITY:
+ switch (chan->channel2) {
+ case IIO_MOD_RUNNING:
+ *val = st->activity_running;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_MOD_WALKING:
+ *val = st->activity_walking;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+ case IIO_CHAN_INFO_OFFSET:
+ /* only single ended adc -> 7 */
+ *val = 7;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ switch (chan->differential) {
+ case 0:
+ /* only single ended adc -> 0.001333 */
+ *val = 0;
+ *val2 = 1333;
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ case 1:
++ /* all differential adc -> 0.000001344 */
+ *val = 0;
+ *val2 = 1344;
+ ret = IIO_VAL_INT_PLUS_NANO;
+ }
+ break;
+ default:
+ break;
+ }
+ break;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ /* only the acceleration axis - read from cache */
+ *val = st->accel_calibbias;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = st->accel_calibscale->val;
+ *val2 = st->accel_calibscale->val2;
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = 3;
+ *val2 = 33;
+ ret = IIO_VAL_INT_PLUS_NANO;
+ break;
+ case IIO_CHAN_INFO_ENABLE:
+ switch (chan->type) {
+ case IIO_STEPS:
+ *val = st->steps_enabled;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ break;
+ }
+ break;
+ case IIO_CHAN_INFO_CALIBHEIGHT:
+ switch (chan->type) {
+ case IIO_STEPS:
+ *val = st->height;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ break;
+ }
+ break;
+
+ default:
+ break;
+ }
+ mutex_unlock(&st->lock);
+ return ret;
+ }
+
+ /**
+ * iio_dummy_write_raw() - data write function.
+ * @indio_dev: the struct iio_dev associated with this device instance
+ * @chan: the channel whose data is to be written
+ * @val: first element of value to set (typically INT)
+ * @val2: second element of value to set (typically MICRO)
+ * @mask: what we actually want to write as per the info_mask_*
+ * in iio_chan_spec.
+ *
+ * Note that all raw writes are assumed IIO_VAL_INT and info mask elements
+ * are assumed to be IIO_INT_PLUS_MICRO unless the callback write_raw_get_fmt
+ * in struct iio_info is provided by the driver.
+ */
+ static int iio_dummy_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+ {
+ int i;
+ int ret = 0;
+ struct iio_dummy_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_VOLTAGE:
+ if (chan->output == 0)
+ return -EINVAL;
+
+ /* Locking not required as writing single value */
+ mutex_lock(&st->lock);
+ st->dac_val = val;
+ mutex_unlock(&st->lock);
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_PROCESSED:
+ switch (chan->type) {
+ case IIO_STEPS:
+ mutex_lock(&st->lock);
+ st->steps = val;
+ mutex_unlock(&st->lock);
+ return 0;
+ case IIO_ACTIVITY:
+ if (val < 0)
+ val = 0;
+ if (val > 100)
+ val = 100;
+ switch (chan->channel2) {
+ case IIO_MOD_RUNNING:
+ st->activity_running = val;
+ return 0;
+ case IIO_MOD_WALKING:
+ st->activity_walking = val;
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_CALIBSCALE:
+ mutex_lock(&st->lock);
+ /* Compare against table - hard matching here */
+ for (i = 0; i < ARRAY_SIZE(dummy_scales); i++)
+ if (val == dummy_scales[i].val &&
+ val2 == dummy_scales[i].val2)
+ break;
+ if (i == ARRAY_SIZE(dummy_scales))
+ ret = -EINVAL;
+ else
+ st->accel_calibscale = &dummy_scales[i];
+ mutex_unlock(&st->lock);
+ return ret;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ mutex_lock(&st->lock);
+ st->accel_calibbias = val;
+ mutex_unlock(&st->lock);
+ return 0;
+ case IIO_CHAN_INFO_ENABLE:
+ switch (chan->type) {
+ case IIO_STEPS:
+ mutex_lock(&st->lock);
+ st->steps_enabled = val;
+ mutex_unlock(&st->lock);
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_CALIBHEIGHT:
+ switch (chan->type) {
+ case IIO_STEPS:
+ st->height = val;
+ return 0;
+ default:
+ return -EINVAL;
+ }
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Device type specific information.
+ */
+ static const struct iio_info iio_dummy_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &iio_dummy_read_raw,
+ .write_raw = &iio_dummy_write_raw,
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ .read_event_config = &iio_simple_dummy_read_event_config,
+ .write_event_config = &iio_simple_dummy_write_event_config,
+ .read_event_value = &iio_simple_dummy_read_event_value,
+ .write_event_value = &iio_simple_dummy_write_event_value,
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ };
+
+ /**
+ * iio_dummy_init_device() - device instance specific init
+ * @indio_dev: the iio device structure
+ *
+ * Most drivers have one of these to set up default values,
+ * reset the device to known state etc.
+ */
+ static int iio_dummy_init_device(struct iio_dev *indio_dev)
+ {
+ struct iio_dummy_state *st = iio_priv(indio_dev);
+
+ st->dac_val = 0;
+ st->single_ended_adc_val = 73;
+ st->differential_adc_val[0] = 33;
+ st->differential_adc_val[1] = -34;
+ st->accel_val = 34;
+ st->accel_calibbias = -7;
+ st->accel_calibscale = &dummy_scales[0];
+ st->steps = 47;
+ st->activity_running = 98;
+ st->activity_walking = 4;
+
+ return 0;
+ }
+
+ /**
+ * iio_dummy_probe() - device instance probe
+ * @index: an id number for this instance.
+ *
+ * Arguments are bus type specific.
+ * I2C: iio_dummy_probe(struct i2c_client *client,
+ * const struct i2c_device_id *id)
+ * SPI: iio_dummy_probe(struct spi_device *spi)
+ */
+ static int iio_dummy_probe(int index)
+ {
+ int ret;
+ struct iio_dev *indio_dev;
+ struct iio_dummy_state *st;
+
+ /*
+ * Allocate an IIO device.
+ *
+ * This structure contains all generic state
+ * information about the device instance.
+ * It also has a region (accessed by iio_priv()
+ * for chip specific state information.
+ */
+ indio_dev = iio_device_alloc(sizeof(*st));
+ if (!indio_dev) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ st = iio_priv(indio_dev);
+ mutex_init(&st->lock);
+
+ iio_dummy_init_device(indio_dev);
+ /*
+ * With hardware: Set the parent device.
+ * indio_dev->dev.parent = &spi->dev;
+ * indio_dev->dev.parent = &client->dev;
+ */
+
+ /*
+ * Make the iio_dev struct available to remove function.
+ * Bus equivalents
+ * i2c_set_clientdata(client, indio_dev);
+ * spi_set_drvdata(spi, indio_dev);
+ */
+ iio_dummy_devs[index] = indio_dev;
+
+ /*
+ * Set the device name.
+ *
+ * This is typically a part number and obtained from the module
+ * id table.
+ * e.g. for i2c and spi:
+ * indio_dev->name = id->name;
+ * indio_dev->name = spi_get_device_id(spi)->name;
+ */
+ indio_dev->name = iio_dummy_part_number;
+
+ /* Provide description of available channels */
+ indio_dev->channels = iio_dummy_channels;
+ indio_dev->num_channels = ARRAY_SIZE(iio_dummy_channels);
+
+ /*
+ * Provide device type specific interface functions and
+ * constant data.
+ */
+ indio_dev->info = &iio_dummy_info;
+
+ /* Specify that device provides sysfs type interfaces */
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = iio_simple_dummy_events_register(indio_dev);
+ if (ret < 0)
+ goto error_free_device;
+
+ ret = iio_simple_dummy_configure_buffer(indio_dev);
+ if (ret < 0)
+ goto error_unregister_events;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ goto error_unconfigure_buffer;
+
+ return 0;
+ error_unconfigure_buffer:
+ iio_simple_dummy_unconfigure_buffer(indio_dev);
+ error_unregister_events:
+ iio_simple_dummy_events_unregister(indio_dev);
+ error_free_device:
+ iio_device_free(indio_dev);
+ error_ret:
+ return ret;
+ }
+
+ /**
+ * iio_dummy_remove() - device instance removal function
+ * @index: device index.
+ *
+ * Parameters follow those of iio_dummy_probe for buses.
+ */
+ static void iio_dummy_remove(int index)
+ {
+ /*
+ * Get a pointer to the device instance iio_dev structure
+ * from the bus subsystem. E.g.
+ * struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ * struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ */
+ struct iio_dev *indio_dev = iio_dummy_devs[index];
+
+ /* Unregister the device */
+ iio_device_unregister(indio_dev);
+
+ /* Device specific code to power down etc */
+
+ /* Buffered capture related cleanup */
+ iio_simple_dummy_unconfigure_buffer(indio_dev);
+
+ iio_simple_dummy_events_unregister(indio_dev);
+
+ /* Free all structures */
+ iio_device_free(indio_dev);
+ }
+
+ /**
+ * iio_dummy_init() - device driver registration
+ *
+ * Varies depending on bus type of the device. As there is no device
+ * here, call probe directly. For information on device registration
+ * i2c:
+ * Documentation/i2c/writing-clients
+ * spi:
+ * Documentation/spi/spi-summary
+ */
+ static __init int iio_dummy_init(void)
+ {
+ int i, ret;
+
+ if (instances > 10) {
+ instances = 1;
+ return -EINVAL;
+ }
+
+ /* Fake a bus */
+ iio_dummy_devs = kcalloc(instances, sizeof(*iio_dummy_devs),
+ GFP_KERNEL);
+ /* Here we have no actual device so call probe */
+ for (i = 0; i < instances; i++) {
+ ret = iio_dummy_probe(i);
+ if (ret < 0)
+ goto error_remove_devs;
+ }
+ return 0;
+
+ error_remove_devs:
+ while (i--)
+ iio_dummy_remove(i);
+
+ kfree(iio_dummy_devs);
+ return ret;
+ }
+ module_init(iio_dummy_init);
+
+ /**
+ * iio_dummy_exit() - device driver removal
+ *
+ * Varies depending on bus type of the device.
+ * As there is no device here, call remove directly.
+ */
+ static __exit void iio_dummy_exit(void)
+ {
+ int i;
+
+ for (i = 0; i < instances; i++)
+ iio_dummy_remove(i);
+ kfree(iio_dummy_devs);
+ }
+ module_exit(iio_dummy_exit);
+
+ MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>");
+ MODULE_DESCRIPTION("IIO dummy driver");
+ MODULE_LICENSE("GPL v2");
--- /dev/null
- * @voltage0: the single ended voltage channel
- * @diffvoltage1m2: first differential channel
- * @diffvoltage3m4: second differenial channel
- * @accelx: acceleration channel
+ /**
+ * Copyright (c) 2011 Jonathan Cameron
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * Join together the various functionality of iio_simple_dummy driver
+ */
+
+ #ifndef _IIO_SIMPLE_DUMMY_H_
+ #define _IIO_SIMPLE_DUMMY_H_
+ #include <linux/kernel.h>
+
+ struct iio_dummy_accel_calibscale;
+ struct iio_dummy_regs;
+
+ /**
+ * struct iio_dummy_state - device instance specific state.
+ * @dac_val: cache for dac value
+ * @single_ended_adc_val: cache for single ended adc value
+ * @differential_adc_val: cache for differential adc value
+ * @accel_val: cache for acceleration value
+ * @accel_calibbias: cache for acceleration calibbias
+ * @accel_calibscale: cache for acceleration calibscale
+ * @lock: lock to ensure state is consistent
+ * @event_irq: irq number for event line (faked)
+ * @event_val: cache for event threshold value
+ * @event_en: cache of whether event is enabled
+ */
+ struct iio_dummy_state {
+ int dac_val;
+ int single_ended_adc_val;
+ int differential_adc_val[2];
+ int accel_val;
+ int accel_calibbias;
+ int activity_running;
+ int activity_walking;
+ const struct iio_dummy_accel_calibscale *accel_calibscale;
+ struct mutex lock;
+ struct iio_dummy_regs *regs;
+ int steps_enabled;
+ int steps;
+ int height;
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+ int event_irq;
+ int event_val;
+ bool event_en;
+ s64 event_timestamp;
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */
+ };
+
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS
+
+ struct iio_dev;
+
+ int iio_simple_dummy_read_event_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir);
+
+ int iio_simple_dummy_write_event_config(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ int state);
+
+ int iio_simple_dummy_read_event_value(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info, int *val,
+ int *val2);
+
+ int iio_simple_dummy_write_event_value(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ enum iio_event_type type,
+ enum iio_event_direction dir,
+ enum iio_event_info info, int val,
+ int val2);
+
+ int iio_simple_dummy_events_register(struct iio_dev *indio_dev);
+ void iio_simple_dummy_events_unregister(struct iio_dev *indio_dev);
+
+ #else /* Stubs for when events are disabled at compile time */
+
+ static inline int
+ iio_simple_dummy_events_register(struct iio_dev *indio_dev)
+ {
+ return 0;
+ };
+
+ static inline void
+ iio_simple_dummy_events_unregister(struct iio_dev *indio_dev)
+ { };
+
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS*/
+
+ /**
+ * enum iio_simple_dummy_scan_elements - scan index enum
- voltage0,
- diffvoltage1m2,
- diffvoltage3m4,
- accelx,
++ * @DUMMY_INDEX_VOLTAGE_0: the single ended voltage channel
++ * @DUMMY_INDEX_DIFFVOLTAGE_1M2: first differential channel
++ * @DUMMY_INDEX_DIFFVOLTAGE_3M4: second differential channel
++ * @DUMMY_INDEX_ACCELX: acceleration channel
+ *
+ * Enum provides convenient numbering for the scan index.
+ */
+ enum iio_simple_dummy_scan_elements {
++ DUMMY_INDEX_VOLTAGE_0,
++ DUMMY_INDEX_DIFFVOLTAGE_1M2,
++ DUMMY_INDEX_DIFFVOLTAGE_3M4,
++ DUMMY_INDEX_ACCELX,
+ };
+
+ #ifdef CONFIG_IIO_SIMPLE_DUMMY_BUFFER
+ int iio_simple_dummy_configure_buffer(struct iio_dev *indio_dev);
+ void iio_simple_dummy_unconfigure_buffer(struct iio_dev *indio_dev);
+ #else
+ static inline int iio_simple_dummy_configure_buffer(struct iio_dev *indio_dev)
+ {
+ return 0;
+ };
+
+ static inline
+ void iio_simple_dummy_unconfigure_buffer(struct iio_dev *indio_dev)
+ {};
+
+ #endif /* CONFIG_IIO_SIMPLE_DUMMY_BUFFER */
+ #endif /* _IIO_SIMPLE_DUMMY_H_ */
--- /dev/null
- [voltage0] = 7,
- [diffvoltage1m2] = -33,
- [diffvoltage3m4] = -2,
- [accelx] = 344,
+ /**
+ * Copyright (c) 2011 Jonathan Cameron
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * Buffer handling elements of industrial I/O reference driver.
+ * Uses the kfifo buffer.
+ *
+ * To test without hardware use the sysfs trigger.
+ */
+
+ #include <linux/kernel.h>
+ #include <linux/export.h>
+ #include <linux/slab.h>
+ #include <linux/interrupt.h>
+ #include <linux/irq.h>
+ #include <linux/bitmap.h>
+
+ #include <linux/iio/iio.h>
+ #include <linux/iio/trigger_consumer.h>
+ #include <linux/iio/kfifo_buf.h>
+
+ #include "iio_simple_dummy.h"
+
+ /* Some fake data */
+
+ static const s16 fakedata[] = {
++ [DUMMY_INDEX_VOLTAGE_0] = 7,
++ [DUMMY_INDEX_DIFFVOLTAGE_1M2] = -33,
++ [DUMMY_INDEX_DIFFVOLTAGE_3M4] = -2,
++ [DUMMY_INDEX_ACCELX] = 344,
+ };
+
+ /**
+ * iio_simple_dummy_trigger_h() - the trigger handler function
+ * @irq: the interrupt number
+ * @p: private data - always a pointer to the poll func.
+ *
+ * This is the guts of buffered capture. On a trigger event occurring,
+ * if the pollfunc is attached then this handler is called as a threaded
+ * interrupt (and hence may sleep). It is responsible for grabbing data
+ * from the device and pushing it into the associated buffer.
+ */
+ static irqreturn_t iio_simple_dummy_trigger_h(int irq, void *p)
+ {
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ int len = 0;
+ u16 *data;
+
+ data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
+ if (!data)
+ goto done;
+
+ if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength)) {
+ /*
+ * Three common options here:
+ * hardware scans: certain combinations of channels make
+ * up a fast read. The capture will consist of all of them.
+ * Hence we just call the grab data function and fill the
+ * buffer without processing.
+ * software scans: can be considered to be random access
+ * so efficient reading is just a case of minimal bus
+ * transactions.
+ * software culled hardware scans:
+ * occasionally a driver may process the nearest hardware
+ * scan to avoid storing elements that are not desired. This
+ * is the fiddliest option by far.
+ * Here let's pretend we have random access. And the values are
+ * in the constant table fakedata.
+ */
+ int i, j;
+
+ for (i = 0, j = 0;
+ i < bitmap_weight(indio_dev->active_scan_mask,
+ indio_dev->masklength);
+ i++, j++) {
+ j = find_next_bit(indio_dev->active_scan_mask,
+ indio_dev->masklength, j);
+ /* random access read from the 'device' */
+ data[i] = fakedata[j];
+ len += 2;
+ }
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, data, iio_get_time_ns());
+
+ kfree(data);
+
+ done:
+ /*
+ * Tell the core we are done with this trigger and ready for the
+ * next one.
+ */
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+ }
+
+ static const struct iio_buffer_setup_ops iio_simple_dummy_buffer_setup_ops = {
+ /*
+ * iio_triggered_buffer_postenable:
+ * Generic function that simply attaches the pollfunc to the trigger.
+ * Replace this to mess with hardware state before we attach the
+ * trigger.
+ */
+ .postenable = &iio_triggered_buffer_postenable,
+ /*
+ * iio_triggered_buffer_predisable:
+ * Generic function that simple detaches the pollfunc from the trigger.
+ * Replace this to put hardware state back again after the trigger is
+ * detached but before userspace knows we have disabled the ring.
+ */
+ .predisable = &iio_triggered_buffer_predisable,
+ };
+
+ int iio_simple_dummy_configure_buffer(struct iio_dev *indio_dev)
+ {
+ int ret;
+ struct iio_buffer *buffer;
+
+ /* Allocate a buffer to use - here a kfifo */
+ buffer = iio_kfifo_allocate();
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto error_ret;
+ }
+
+ iio_device_attach_buffer(indio_dev, buffer);
+
+ /* Enable timestamps by default */
+ buffer->scan_timestamp = true;
+
+ /*
+ * Tell the core what device type specific functions should
+ * be run on either side of buffer capture enable / disable.
+ */
+ indio_dev->setup_ops = &iio_simple_dummy_buffer_setup_ops;
+
+ /*
+ * Configure a polling function.
+ * When a trigger event with this polling function connected
+ * occurs, this function is run. Typically this grabs data
+ * from the device.
+ *
+ * NULL for the bottom half. This is normally implemented only if we
+ * either want to ping a capture now pin (no sleeping) or grab
+ * a timestamp as close as possible to a data ready trigger firing.
+ *
+ * IRQF_ONESHOT ensures irqs are masked such that only one instance
+ * of the handler can run at a time.
+ *
+ * "iio_simple_dummy_consumer%d" formatting string for the irq 'name'
+ * as seen under /proc/interrupts. Remaining parameters as per printk.
+ */
+ indio_dev->pollfunc = iio_alloc_pollfunc(NULL,
+ &iio_simple_dummy_trigger_h,
+ IRQF_ONESHOT,
+ indio_dev,
+ "iio_simple_dummy_consumer%d",
+ indio_dev->id);
+
+ if (!indio_dev->pollfunc) {
+ ret = -ENOMEM;
+ goto error_free_buffer;
+ }
+
+ /*
+ * Notify the core that this device is capable of buffered capture
+ * driven by a trigger.
+ */
+ indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
+
+ return 0;
+
+ error_free_buffer:
+ iio_kfifo_free(indio_dev->buffer);
+ error_ret:
+ return ret;
+ }
+
+ /**
+ * iio_simple_dummy_unconfigure_buffer() - release buffer resources
+ * @indo_dev: device instance state
+ */
+ void iio_simple_dummy_unconfigure_buffer(struct iio_dev *indio_dev)
+ {
+ iio_dealloc_pollfunc(indio_dev->pollfunc);
+ iio_kfifo_free(indio_dev->buffer);
+ }
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