diff options
| -rw-r--r-- | drivers/staging/iio/Kconfig | 20 | ||||
| -rw-r--r-- | drivers/staging/iio/Makefile | 6 | ||||
| -rw-r--r-- | drivers/staging/iio/iio_dummy_evgen.c | 217 | ||||
| -rw-r--r-- | drivers/staging/iio/iio_dummy_evgen.h | 2 | ||||
| -rw-r--r-- | drivers/staging/iio/iio_simple_dummy.c | 53 | ||||
| -rw-r--r-- | drivers/staging/iio/iio_simple_dummy.h | 81 | ||||
| -rw-r--r-- | drivers/staging/iio/iio_simple_dummy_events.c | 190 |
7 files changed, 543 insertions, 26 deletions
diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig index 0accc21..75128a0 100644 --- a/drivers/staging/iio/Kconfig +++ b/drivers/staging/iio/Kconfig @@ -70,12 +70,26 @@ source "drivers/staging/iio/meter/Kconfig" source "drivers/staging/iio/resolver/Kconfig" source "drivers/staging/iio/trigger/Kconfig" +config IIO_DUMMY_EVGEN + tristate + config IIO_SIMPLE_DUMMY tristate "An example driver with no hardware requirements" + select IIO_SIMPLE_DUMMY_EVGEN if IIO_SIMPLE_DUMMY_EVENTS help - Driver intended mainly as documentation for how to write - a driver. May also be useful for testing userspace code - without hardward. + Driver intended mainly as documentation for how to write + a driver. May also be useful for testing userspace code + without hardward. + +if IIO_SIMPLE_DUMMY + +config IIO_SIMPLE_DUMMY_EVENTS + boolean "Event generation support" + select IIO_DUMMY_EVGEN + help + Add some dummy events to the simple dummy driver. + +endif # IIO_SIMPLE_DUMMY endif # IIO diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile index 014d8f1..75aacfd 100644 --- a/drivers/staging/iio/Makefile +++ b/drivers/staging/iio/Makefile @@ -10,7 +10,11 @@ industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o obj-$(CONFIG_IIO_SW_RING) += ring_sw.o obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o -obj-$(CONFIG_IIO_SIMPLE_DUMMY) += iio_simple_dummy.o +obj-$(CONFIG_IIO_SIMPLE_DUMMY) += iio_dummy.o +iio_dummy-y := iio_simple_dummy.o +iio_dummy-$(CONFIG_IIO_SIMPLE_DUMMY_EVENTS) += iio_simple_dummy_events.o + +obj-$(CONFIG_IIO_DUMMY_EVGEN) += iio_dummy_evgen.o obj-y += accel/ obj-y += adc/ diff --git a/drivers/staging/iio/iio_dummy_evgen.c b/drivers/staging/iio/iio_dummy_evgen.c new file mode 100644 index 0000000..da657d1 --- /dev/null +++ b/drivers/staging/iio/iio_dummy_evgen.c @@ -0,0 +1,217 @@ +/** + * 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. + * + * Companion module to the iio simple dummy example driver. + * The purpose of this is to generate 'fake' event interrupts thus + * allowing that driver's code to be as close as possible to that of + * a normal driver talking to hardware. The approach used here + * is not intended to be general and just happens to work for this + * particular use case. + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/mutex.h> +#include <linux/module.h> +#include <linux/sysfs.h> + +#include "iio_dummy_evgen.h" +#include "iio.h" +#include "sysfs.h" + +/* Fiddly bit of faking and irq without hardware */ +#define IIO_EVENTGEN_NO 10 +/** + * struct iio_dummy_evgen - evgen state + * @chip: irq chip we are faking + * @base: base of irq range + * @enabled: mask of which irqs are enabled + * @inuse: mask of which irqs actually have anyone connected + * @lock: protect the evgen state + */ +struct iio_dummy_eventgen { + struct irq_chip chip; + int base; + bool enabled[IIO_EVENTGEN_NO]; + bool inuse[IIO_EVENTGEN_NO]; + struct mutex lock; +}; + +/* We can only ever have one instance of this 'device' */ +static struct iio_dummy_eventgen *iio_evgen; +static const char *iio_evgen_name = "iio_dummy_evgen"; + +static void iio_dummy_event_irqmask(struct irq_data *d) +{ + struct irq_chip *chip = irq_data_get_irq_chip(d); + struct iio_dummy_eventgen *evgen = + container_of(chip, struct iio_dummy_eventgen, chip); + + evgen->enabled[d->irq - evgen->base] = false; +} + +static void iio_dummy_event_irqunmask(struct irq_data *d) +{ + struct irq_chip *chip = irq_data_get_irq_chip(d); + struct iio_dummy_eventgen *evgen = + container_of(chip, struct iio_dummy_eventgen, chip); + + evgen->enabled[d->irq - evgen->base] = true; +} + +static int iio_dummy_evgen_create(void) +{ + int ret, i; + + iio_evgen = kzalloc(sizeof(*iio_evgen), GFP_KERNEL); + if (iio_evgen == NULL) + return -ENOMEM; + + iio_evgen->base = irq_alloc_descs(-1, 0, IIO_EVENTGEN_NO, 0); + if (iio_evgen->base < 0) { + ret = iio_evgen->base; + kfree(iio_evgen); + return ret; + } + iio_evgen->chip.name = iio_evgen_name; + iio_evgen->chip.irq_mask = &iio_dummy_event_irqmask; + iio_evgen->chip.irq_unmask = &iio_dummy_event_irqunmask; + for (i = 0; i < IIO_EVENTGEN_NO; i++) { + irq_set_chip(iio_evgen->base + i, &iio_evgen->chip); + irq_set_handler(iio_evgen->base + i, &handle_simple_irq); + irq_modify_status(iio_evgen->base + i, + IRQ_NOREQUEST | IRQ_NOAUTOEN, + IRQ_NOPROBE); + } + mutex_init(&iio_evgen->lock); + return 0; +} + +/** + * iio_dummy_evgen_get_irq() - get an evgen provided irq for a device + * + * This function will give a free allocated irq to a client device. + * That irq can then be caused to 'fire' by using the associated sysfs file. + */ +int iio_dummy_evgen_get_irq(void) +{ + int i, ret = 0; + mutex_lock(&iio_evgen->lock); + for (i = 0; i < IIO_EVENTGEN_NO; i++) + if (iio_evgen->inuse[i] == false) { + ret = iio_evgen->base + i; + iio_evgen->inuse[i] = true; + break; + } + mutex_unlock(&iio_evgen->lock); + if (i == IIO_EVENTGEN_NO) + return -ENOMEM; + return ret; +} +EXPORT_SYMBOL_GPL(iio_dummy_evgen_get_irq); + +/** + * iio_dummy_evgen_release_irq() - give the irq back. + * @irq: irq being returned to the pool + * + * Used by client driver instances to give the irqs back when they disconnect + */ +int iio_dummy_evgen_release_irq(int irq) +{ + mutex_lock(&iio_evgen->lock); + iio_evgen->inuse[irq - iio_evgen->base] = false; + mutex_unlock(&iio_evgen->lock); + + return 0; +} +EXPORT_SYMBOL_GPL(iio_dummy_evgen_release_irq); + +static void iio_dummy_evgen_free(void) +{ + irq_free_descs(iio_evgen->base, IIO_EVENTGEN_NO); + kfree(iio_evgen); +} + +static void iio_evgen_release(struct device *dev) +{ + iio_dummy_evgen_free(); +} + +static ssize_t iio_evgen_poke(struct device *dev, + struct device_attribute *attr, + const char *buf, + size_t len) +{ + struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); + + if (iio_evgen->enabled[this_attr->address]) + handle_nested_irq(iio_evgen->base + this_attr->address); + + return len; +} + +static IIO_DEVICE_ATTR(poke_ev0, S_IWUSR, NULL, &iio_evgen_poke, 0); +static IIO_DEVICE_ATTR(poke_ev1, S_IWUSR, NULL, &iio_evgen_poke, 1); +static IIO_DEVICE_ATTR(poke_ev2, S_IWUSR, NULL, &iio_evgen_poke, 2); +static IIO_DEVICE_ATTR(poke_ev3, S_IWUSR, NULL, &iio_evgen_poke, 3); +static IIO_DEVICE_ATTR(poke_ev4, S_IWUSR, NULL, &iio_evgen_poke, 4); +static IIO_DEVICE_ATTR(poke_ev5, S_IWUSR, NULL, &iio_evgen_poke, 5); +static IIO_DEVICE_ATTR(poke_ev6, S_IWUSR, NULL, &iio_evgen_poke, 6); +static IIO_DEVICE_ATTR(poke_ev7, S_IWUSR, NULL, &iio_evgen_poke, 7); +static IIO_DEVICE_ATTR(poke_ev8, S_IWUSR, NULL, &iio_evgen_poke, 8); +static IIO_DEVICE_ATTR(poke_ev9, S_IWUSR, NULL, &iio_evgen_poke, 9); + +static struct attribute *iio_evgen_attrs[] = { + &iio_dev_attr_poke_ev0.dev_attr.attr, + &iio_dev_attr_poke_ev1.dev_attr.attr, + &iio_dev_attr_poke_ev2.dev_attr.attr, + &iio_dev_attr_poke_ev3.dev_attr.attr, + &iio_dev_attr_poke_ev4.dev_attr.attr, + &iio_dev_attr_poke_ev5.dev_attr.attr, + &iio_dev_attr_poke_ev6.dev_attr.attr, + &iio_dev_attr_poke_ev7.dev_attr.attr, + &iio_dev_attr_poke_ev8.dev_attr.attr, + &iio_dev_attr_poke_ev9.dev_attr.attr, + NULL, +}; + +static const struct attribute_group iio_evgen_group = { + .attrs = iio_evgen_attrs, +}; + +static const struct attribute_group *iio_evgen_groups[] = { + &iio_evgen_group, + NULL +}; + +static struct device iio_evgen_dev = { + .bus = &iio_bus_type, + .groups = iio_evgen_groups, + .release = &iio_evgen_release, +}; +static __init int iio_dummy_evgen_init(void) +{ + int ret = iio_dummy_evgen_create(); + if (ret < 0) + return ret; + device_initialize(&iio_evgen_dev); + dev_set_name(&iio_evgen_dev, "iio_evgen"); + return device_add(&iio_evgen_dev); +} +module_init(iio_dummy_evgen_init); + +static __exit void iio_dummy_evgen_exit(void) +{ + device_unregister(&iio_evgen_dev); +} +module_exit(iio_dummy_evgen_exit); + +MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>"); +MODULE_DESCRIPTION("IIO dummy driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/staging/iio/iio_dummy_evgen.h b/drivers/staging/iio/iio_dummy_evgen.h new file mode 100644 index 0000000..d8845e2 --- /dev/null +++ b/drivers/staging/iio/iio_dummy_evgen.h @@ -0,0 +1,2 @@ +int iio_dummy_evgen_get_irq(void); +int iio_dummy_evgen_release_irq(int irq); diff --git a/drivers/staging/iio/iio_simple_dummy.c b/drivers/staging/iio/iio_simple_dummy.c index 314a4a6..c5119a0 100644 --- a/drivers/staging/iio/iio_simple_dummy.c +++ b/drivers/staging/iio/iio_simple_dummy.c @@ -20,6 +20,8 @@ #include <linux/moduleparam.h> #include "iio.h" +#include "sysfs.h" +#include "iio_simple_dummy.h" /* * A few elements needed to fake a bus for this driver @@ -53,26 +55,6 @@ static const struct iio_dummy_accel_calibscale dummy_scales[] = { { 733, 13, 0x9 }, /* 733.00013 */ }; -/** - * 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 - */ -struct iio_dummy_state { - int dac_val; - int single_ended_adc_val; - int differential_adc_val[2]; - int accel_val; - int accel_calibbias; - const struct iio_dummy_accel_calibscale *accel_calibscale; - struct mutex lock; -}; - /* * iio_dummy_channels - Description of available channels * @@ -101,6 +83,14 @@ static struct iio_chan_spec iio_dummy_channels[] = { */ (1 << IIO_CHAN_INFO_SCALE_SEPARATE), +#ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS + /* + * simple event - triggered when value rises above + * a threshold + */ + .event_mask = IIO_EV_BIT(IIO_EV_TYPE_THRESH, + IIO_EV_DIR_RISING), +#endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS */ }, /* Differential ADC channel in_voltage1-voltage2_raw etc*/ { @@ -296,6 +286,12 @@ 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 */ }; /** @@ -392,11 +388,16 @@ static int __devinit iio_dummy_probe(int index) /* Specify that device provides sysfs type interfaces */ indio_dev->modes = INDIO_DIRECT_MODE; - ret = iio_device_register(indio_dev); + ret = iio_simple_dummy_events_register(indio_dev); if (ret < 0) goto error_free_device; + ret = iio_device_register(indio_dev); + if (ret < 0) + goto error_unregister_events; return 0; +error_unregister_events: + iio_simple_dummy_events_unregister(indio_dev); error_free_device: /* Note free device should only be called, before registration * has succeeded. */ @@ -413,6 +414,7 @@ error_ret: */ static int iio_dummy_remove(int index) { + int ret; /* * Get a pointer to the device instance iio_dev structure * from the bus subsystem. E.g. @@ -421,15 +423,22 @@ static int iio_dummy_remove(int index) */ struct iio_dev *indio_dev = iio_dummy_devs[index]; + /* Unregister the device */ iio_device_unregister(indio_dev); /* Device specific code to power down etc */ + + ret = iio_simple_dummy_events_unregister(indio_dev); + if (ret) + goto error_ret; + /* Free all structures */ iio_free_device(indio_dev); - return 0; +error_ret: + return ret; } /** diff --git a/drivers/staging/iio/iio_simple_dummy.h b/drivers/staging/iio/iio_simple_dummy.h new file mode 100644 index 0000000..998fd1f --- /dev/null +++ b/drivers/staging/iio/iio_simple_dummy.h @@ -0,0 +1,81 @@ +/** + * 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 + */ + +#include <linux/kernel.h> + +struct iio_dummy_accel_calibscale; + +/** + * 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 theshold 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; + const struct iio_dummy_accel_calibscale *accel_calibscale; + struct mutex lock; +#ifdef CONFIG_IIO_SIMPLE_DUMMY_EVENTS + int event_irq; + int event_val; + bool event_en; +#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, + u64 event_code); + +int iio_simple_dummy_write_event_config(struct iio_dev *indio_dev, + u64 event_code, + int state); + +int iio_simple_dummy_read_event_value(struct iio_dev *indio_dev, + u64 event_code, + int *val); + +int iio_simple_dummy_write_event_value(struct iio_dev *indio_dev, + u64 event_code, + int val); + +int iio_simple_dummy_events_register(struct iio_dev *indio_dev); +int 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 int +iio_simple_dummy_events_unregister(struct iio_dev *indio_dev) +{ + return 0; +}; + +#endif /* CONFIG_IIO_SIMPLE_DUMMY_EVENTS*/ + + diff --git a/drivers/staging/iio/iio_simple_dummy_events.c b/drivers/staging/iio/iio_simple_dummy_events.c new file mode 100644 index 0000000..9f00cff --- /dev/null +++ b/drivers/staging/iio/iio_simple_dummy_events.c @@ -0,0 +1,190 @@ +/** + * 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. + * + * Event handling elements of industrial I/O reference driver. + */ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/irq.h> + +#include "iio.h" +#include "sysfs.h" +#include "iio_simple_dummy.h" + +/* Evgen 'fakes' interrupt events for this example */ +#include "iio_dummy_evgen.h" + +/** + * iio_simple_dummy_read_event_config() - is event enabled? + * @indio_dev: the device instance data + * @event_code: event code of the event being queried + * + * This function would normally query the relevant registers or a cache to + * discover if the event generation is enabled on the device. + */ +int iio_simple_dummy_read_event_config(struct iio_dev *indio_dev, + u64 event_code) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + + return st->event_en; +} + +/** + * iio_simple_dummy_write_event_config() - set whether event is enabled + * @indio_dev: the device instance data + * @event_code: event code of event being enabled/disabled + * @state: whether to enable or disable the device. + * + * This function would normally set the relevant registers on the devices + * so that it generates the specified event. Here it just sets up a cached + * value. + */ +int iio_simple_dummy_write_event_config(struct iio_dev *indio_dev, + u64 event_code, + int state) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + + /* + * Deliberately over the top code splitting to illustrate + * how this is done when multiple events exist. + */ + switch (IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event_code)) { + case IIO_VOLTAGE: + switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) { + case IIO_EV_TYPE_THRESH: + if (IIO_EVENT_CODE_EXTRACT_DIR(event_code) == + IIO_EV_DIR_RISING) + st->event_en = state; + else + return -EINVAL; + break; + default: + return -EINVAL; + } + default: + return -EINVAL; + } + + return 0; +} + +/** + * iio_simple_dummy_read_event_value() - get value associated with event + * @indio_dev: device instance specific data + * @event_code: event code for the event whose value is being queried + * @val: value for the event code. + * + * Many devices provide a large set of events of which only a subset may + * be enabled at a time, with value registers whose meaning changes depending + * on the event enabled. This often means that the driver must cache the values + * associated with each possible events so that the right value is in place when + * the enabled event is changed. + */ +int iio_simple_dummy_read_event_value(struct iio_dev *indio_dev, + u64 event_code, + int *val) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + + *val = st->event_val; + + return 0; +} + +/** + * iio_simple_dummy_write_event_value() - set value associate with event + * @indio_dev: device instance specific data + * @event_code: event code for the event whose value is being set + * @val: the value to be set. + */ +int iio_simple_dummy_write_event_value(struct iio_dev *indio_dev, + u64 event_code, + int val) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + + st->event_val = val; + + return 0; +} + +/** + * iio_simple_dummy_event_handler() - identify and pass on event + * @irq: irq of event line + * @private: pointer to device instance state. + * + * This handler is responsible for querying the device to find out what + * event occured and for then pushing that event towards userspace. + * Here only one event occurs so we push that directly on with locally + * grabbed timestamp. + */ +static irqreturn_t iio_simple_dummy_event_handler(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + iio_push_event(indio_dev, + IIO_EVENT_CODE(IIO_VOLTAGE, 0, 0, + IIO_EV_DIR_RISING, + IIO_EV_TYPE_THRESH, 0, 0, 0), + iio_get_time_ns()); + return IRQ_HANDLED; +} + +/** + * iio_simple_dummy_events_register() - setup interrupt handling for events + * @indio_dev: device instance data + * + * This function requests the threaded interrupt to handle the events. + * Normally the irq is a hardware interrupt and the number comes + * from board configuration files. Here we get it from a companion + * module that fakes the interrupt for us. Note that module in + * no way forms part of this example. Just assume that events magically + * appear via the provided interrupt. + */ +int iio_simple_dummy_events_register(struct iio_dev *indio_dev) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + int ret; + + /* Fire up event source - normally not present */ + st->event_irq = iio_dummy_evgen_get_irq(); + if (st->event_irq < 0) { + ret = st->event_irq; + goto error_ret; + } + ret = request_threaded_irq(st->event_irq, + NULL, + &iio_simple_dummy_event_handler, + IRQF_ONESHOT, + "iio_simple_event", + indio_dev); + if (ret < 0) + goto error_free_evgen; + return 0; + +error_free_evgen: + iio_dummy_evgen_release_irq(st->event_irq); +error_ret: + return ret; +} + +/** + * iio_simple_dummy_events_unregister() - tidy up interrupt handling on remove + * @indio_dev: device instance data + */ +int iio_simple_dummy_events_unregister(struct iio_dev *indio_dev) +{ + struct iio_dummy_state *st = iio_priv(indio_dev); + + free_irq(st->event_irq, indio_dev); + /* Not part of normal driver */ + iio_dummy_evgen_release_irq(st->event_irq); + + return 0; +} |