On 04/21/11 17:51, Jonathan Cameron wrote:
> Change of plan here.
>
> It's perfectly possible, (but somewhat under utilized) to call irq_alloc_descs
> to give us a dynamically allocated range of irq's. It may be dependant on sparse irq
> though so will need to look into that or provide alternative method such
> as this one.
New implementation using that approach is now available in the iio-onwards tree.
Please take a look. I'd like to start pushing some of this tree
out to Greg asap as it would be good to have it place for a while pre
merge window opening. I'll be posting a new revision of the whole set
sometime in the next few days. Before then I'm trying to squash the remaining
build issues with a few drivers.
Jonathan
>> fix to merge back for the incorrect multiple trigger handling
>>
>> V2: Stop silly name duplication.
>> Move pool handling to industrialio-trigger as that is the only user.
>> Changed over to using irq_modify_status rather than the arm
>> specific set_irq_flags as per Thomas Gleixner's suggestion.
>>
>> Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxx>
>> ---
>> drivers/staging/Makefile | 2 +-
>> drivers/staging/iio/Kconfig | 12 ++
>> drivers/staging/iio/Makefile | 2 +
>> drivers/staging/iio/iio-board-info.h | 24 +++
>> drivers/staging/iio/iio-core.h | 13 ++
>> drivers/staging/iio/industrialio-board-info.c | 25 +++
>> drivers/staging/iio/industrialio-trigger.c | 200 +++++++++++++++++++++----
>> drivers/staging/iio/trigger.h | 57 +++++++-
>> 8 files changed, 298 insertions(+), 37 deletions(-)
>>
>> diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
>> index eb93012..0955c7c 100644
>> --- a/drivers/staging/Makefile
>> +++ b/drivers/staging/Makefile
>> @@ -41,7 +41,7 @@ obj-$(CONFIG_VT6656) += vt6656/
>> obj-$(CONFIG_HYPERV) += hv/
>> obj-$(CONFIG_VME_BUS) += vme/
>> obj-$(CONFIG_DX_SEP) += sep/
>> -obj-$(CONFIG_IIO) += iio/
>> +obj-y += iio/
>> obj-$(CONFIG_CS5535_GPIO) += cs5535_gpio/
>> obj-$(CONFIG_ZRAM) += zram/
>> obj-$(CONFIG_XVMALLOC) += zram/
>> diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig
>> index 6775bf9..df9aa08 100644
>> --- a/drivers/staging/iio/Kconfig
>> +++ b/drivers/staging/iio/Kconfig
>> @@ -12,6 +12,10 @@ menuconfig IIO
>> Documentation/industrialio for more information.
>> if IIO
>>
>> +config IIO_BOARDINFO
>> + boolean
>> + default y
>> +
>> config IIO_RING_BUFFER
>> bool "Enable ring buffer support within IIO"
>> help
>> @@ -42,12 +46,20 @@ endif # IIO_RINGBUFFER
>>
>> config IIO_TRIGGER
>> boolean "Enable triggered sampling support"
>> + depends on IIO_BOARDINFO
>> help
>> Provides IIO core support for triggers. Currently these
>> are used to initialize capture of samples to push into
>> ring buffers. The triggers are effectively a 'capture
>> data now' interrupt.
>>
>> +config IIO_CONSUMERS_PER_TRIGGER
>> + int "Maximum number of consumers per trigger"
>> + depends on IIO_TRIGGER
>> + default "2"
>> + help
>> + This value controls the maximum number of consumers that a
>> + given trigger may handle. Default is 2.
>>
>> source "drivers/staging/iio/accel/Kconfig"
>> source "drivers/staging/iio/adc/Kconfig"
>> diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile
>> index bb5c95c..37b4d12 100644
>> --- a/drivers/staging/iio/Makefile
>> +++ b/drivers/staging/iio/Makefile
>> @@ -2,6 +2,8 @@
>> # Makefile for the industrial I/O core.
>> #
>>
>> +obj-$(CONFIG_IIO_BOARDINFO) += industrialio-board-info.o
>> +
>> obj-$(CONFIG_IIO) += industrialio.o
>> industrialio-y := industrialio-core.o
>> industrialio-$(CONFIG_IIO_RING_BUFFER) += industrialio-ring.o
>> diff --git a/drivers/staging/iio/iio-board-info.h b/drivers/staging/iio/iio-board-info.h
>> new file mode 100644
>> index 0000000..c608a4d
>> --- /dev/null
>> +++ b/drivers/staging/iio/iio-board-info.h
>> @@ -0,0 +1,24 @@
>> +/*
>> + * Board information for IIO.
>> + *
>> + * Copyright (c) 2011 Jonathan Cameron <jic23@xxxxxxxxx>
>> + *
>> + * 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.
>> + */
>> +
>> +#ifdef CONFIG_IIO_BOARDINFO
>> +
>> +/**
>> + * iio_set_irq_pool() - provid iio with a pool of virtaul interrupts to use
>> + * @start: start of the pool
>> + * @num: number of interupts in the pool
>> + **/
>> +void iio_set_irq_pool(int start, int num);
>> +
>> +#else
>> +
>> +static inline void iio_set_irq_pool(int start, int num) {};
>> +
>> +#endif
>> diff --git a/drivers/staging/iio/iio-core.h b/drivers/staging/iio/iio-core.h
>> new file mode 100644
>> index 0000000..2c4f433
>> --- /dev/null
>> +++ b/drivers/staging/iio/iio-core.h
>> @@ -0,0 +1,13 @@
>> +/*
>> + * IIO core header. Should never be included by drivers.
>> + *
>> + * Copyright (c) 2011 Jonathan Cameron <jic23@xxxxxxxxx>
>> + *
>> + * 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.
>> + */
>> +
>> +#define IIO_MAX_POOL 128
>> +extern int __iio_irqstart;
>> +extern int __iio_irqnum;
>> diff --git a/drivers/staging/iio/industrialio-board-info.c b/drivers/staging/iio/industrialio-board-info.c
>> new file mode 100644
>> index 0000000..28f9156
>> --- /dev/null
>> +++ b/drivers/staging/iio/industrialio-board-info.c
>> @@ -0,0 +1,25 @@
>> +/* IIO Board info
>> + *
>> + * 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.
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/kernel.h>
>> +#include "iio-core.h"
>> +
>> +int __iio_irqstart;
>> +EXPORT_SYMBOL(__iio_irqstart);
>> +int __iio_irqnum;
>> +EXPORT_SYMBOL(__iio_irqnum);
>> +
>> +void __init iio_set_irq_pool(int start, int num)
>> +{
>> + __iio_irqstart = start;
>> + __iio_irqnum = num;
>> + if (num > IIO_MAX_POOL)
>> + __iio_irqnum = IIO_MAX_POOL;
>> +}
>> diff --git a/drivers/staging/iio/industrialio-trigger.c b/drivers/staging/iio/industrialio-trigger.c
>> index 083847c..9ccc789 100644
>> --- a/drivers/staging/iio/industrialio-trigger.c
>> +++ b/drivers/staging/iio/industrialio-trigger.c
>> @@ -19,6 +19,7 @@
>> #include "iio.h"
>> #include "trigger.h"
>> #include "trigger_consumer.h"
>> +#include "iio-core.h"
>>
>> /* RFC - Question of approach
>> * Make the common case (single sensor single trigger)
>> @@ -38,6 +39,31 @@ static DEFINE_SPINLOCK(iio_trigger_idr_lock);
>> static LIST_HEAD(iio_trigger_list);
>> static DEFINE_MUTEX(iio_trigger_list_lock);
>>
>> +static DEFINE_MUTEX(iio_irq_pool_lock);
>> +static unsigned long iio_irq_pool_mask[BITS_TO_LONGS(IIO_MAX_POOL)] = {};
>> +
>> +static int iio_irq_pool_get_range(int num)
>> +{
>> + int ret;
>> +
>> + mutex_lock(&iio_irq_pool_lock);
>> + ret = bitmap_find_free_region(iio_irq_pool_mask,
>> + __iio_irqnum, ilog2(num));
>> + if (ret >= 0)
>> + ret += __iio_irqstart;
>> + mutex_unlock(&iio_irq_pool_lock);
>> +
>> + return ret;
>> +}
>> +
>> +static void iio_irq_pool_put_range(int start, int num)
>> +{
>> + mutex_lock(&iio_irq_pool_lock);
>> + bitmap_release_region(iio_irq_pool_mask,
>> + start - __iio_irqstart, ilog2(num));
>> + mutex_unlock(&iio_irq_pool_lock);
>> +}
>> +
>> /**
>> * iio_trigger_register_sysfs() - create a device for this trigger
>> * @trig_info: the trigger
>> @@ -163,6 +189,7 @@ static struct iio_trigger *iio_trigger_find_by_name(const char *name,
>>
>> void iio_trigger_poll(struct iio_trigger *trig, s64 time)
>> {
>> + int i;
>> struct iio_poll_func *pf_cursor;
>>
>> list_for_each_entry(pf_cursor, &trig->pollfunc_list, list) {
>> @@ -178,6 +205,13 @@ void iio_trigger_poll(struct iio_trigger *trig, s64 time)
>> trig->use_count++;
>> }
>> }
>> + if (!trig->use_count) {
>> + for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++)
>> + if (trig->subirqs[i].enabled) {
>> + trig->use_count++;
>> + generic_handle_irq(trig->subirq_base + i);
>> + }
>> + }
>> }
>> EXPORT_SYMBOL(iio_trigger_poll);
>>
>> @@ -219,16 +253,31 @@ int iio_trigger_attach_poll_func(struct iio_trigger *trig,
>> int ret = 0;
>> unsigned long flags;
>>
>> - spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> - list_add_tail(&pf->list, &trig->pollfunc_list);
>> - spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>> -
>> - if (trig->set_trigger_state)
>> - ret = trig->set_trigger_state(trig, true);
>> - if (ret) {
>> - printk(KERN_ERR "set trigger state failed\n");
>> - list_del(&pf->list);
>> + if (pf->thread) {
>> + bool notinuse
>> + = bitmap_empty(trig->pool,
>> + CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> +
>> + pf->irq = iio_trigger_get_irq(trig);
>> + ret = request_threaded_irq(pf->irq, pf->h, pf->thread,
>> + pf->type, pf->name,
>> + pf);
>> + if (trig->set_trigger_state && notinuse) {
>> + ret = trig->set_trigger_state(trig, true);
>> + } else {
>> + spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> + list_add_tail(&pf->list, &trig->pollfunc_list);
>> + spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>> +
>> + if (trig->set_trigger_state)
>> + ret = trig->set_trigger_state(trig, true);
>> + }
>> + if (ret) {
>> + printk(KERN_ERR "set trigger state failed\n");
>> + list_del(&pf->list);
>> + }
>> }
>> +
>> return ret;
>> }
>> EXPORT_SYMBOL(iio_trigger_attach_poll_func);
>> @@ -240,37 +289,63 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
>> unsigned long flags;
>> int ret = -EINVAL;
>>
>> - spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> - list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
>> - if (pf_cursor == pf) {
>> - ret = 0;
>> - break;
>> - }
>> - if (!ret) {
>> - if (list_is_singular(&trig->pollfunc_list)
>> - && trig->set_trigger_state) {
>> - spin_unlock_irqrestore(&trig->pollfunc_list_lock,
>> - flags);
>> - /* May sleep hence cannot hold the spin lock */
>> + if (pf->thread) {
>> + bool no_other_users
>> + = (bitmap_weight(trig->pool,
>> + CONFIG_IIO_CONSUMERS_PER_TRIGGER)
>> + == 1);
>> + if (trig->set_trigger_state && no_other_users) {
>> ret = trig->set_trigger_state(trig, false);
>> if (ret)
>> goto error_ret;
>> - spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> + } else
>> + ret = 0;
>> + iio_trigger_put_irq(trig, pf->irq);
>> + free_irq(pf->irq, pf);
>> + } else {
>> + spin_lock_irqsave(&trig->pollfunc_list_lock, flags);
>> + list_for_each_entry(pf_cursor, &trig->pollfunc_list, list)
>> + if (pf_cursor == pf) {
>> + ret = 0;
>> + break;
>> + }
>> + if (!ret) {
>> + if (list_is_singular(&trig->pollfunc_list)
>> + && trig->set_trigger_state) {
>> + spin_unlock_irqrestore(&trig
>> + ->pollfunc_list_lock,
>> + flags);
>> + /* May sleep hence cannot hold the spin lock */
>> + ret = trig->set_trigger_state(trig, false);
>> + if (ret)
>> + goto error_ret;
>> + spin_lock_irqsave(&trig->pollfunc_list_lock,
>> + flags);
>> + }
>> + /*
>> + * Now we can delete safe in the knowledge that, if
>> + * this is the last pollfunc then we have disabled
>> + * the trigger anyway and so nothing should be able
>> + * to call the pollfunc.
>> + */
>> + list_del(&pf_cursor->list);
>> }
>> - /*
>> - * Now we can delete safe in the knowledge that, if this is
>> - * the last pollfunc then we have disabled the trigger anyway
>> - * and so nothing should be able to call the pollfunc.
>> - */
>> - list_del(&pf_cursor->list);
>> + spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>> }
>> - spin_unlock_irqrestore(&trig->pollfunc_list_lock, flags);
>>
>> error_ret:
>> return ret;
>> }
>> EXPORT_SYMBOL(iio_trigger_dettach_poll_func);
>>
>> +irqreturn_t iio_pollfunc_store_time(int irq, void *p)
>> +{
>> + struct iio_poll_func *pf = p;
>> + pf->timestamp = iio_get_time_ns();
>> + return IRQ_WAKE_THREAD;
>> +}
>> +EXPORT_SYMBOL(iio_pollfunc_store_time);
>> +
>> /**
>> * iio_trigger_read_currrent() - trigger consumer sysfs query which trigger
>> *
>> @@ -337,6 +412,22 @@ static const struct attribute_group iio_trigger_consumer_attr_group = {
>> static void iio_trig_release(struct device *device)
>> {
>> struct iio_trigger *trig = to_iio_trigger(device);
>> + int i;
>> +
>> + if (trig->subirq_base) {
>> + for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
>> + irq_modify_status(trig->subirq_base + i,
>> + IRQ_NOAUTOEN,
>> + IRQ_NOREQUEST | IRQ_NOPROBE);
>> + irq_set_chip(trig->subirq_base + i,
>> + NULL);
>> + irq_set_handler(trig->subirq_base + i,
>> + NULL);
>> + }
>> +
>> + iio_irq_pool_put_range(trig->subirq_base,
>> + CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> + }
>> kfree(trig);
>> iio_put();
>> }
>> @@ -345,11 +436,30 @@ static struct device_type iio_trig_type = {
>> .release = iio_trig_release,
>> };
>>
>> -struct iio_trigger *iio_allocate_trigger(void)
>> +static void iio_trig_subirqmask(struct irq_data *d)
>> +{
>> + struct irq_chip *chip = irq_data_get_irq_chip(d);
>> + struct iio_trigger *trig
>> + = container_of(chip,
>> + struct iio_trigger, subirq_chip);
>> + trig->subirqs[d->irq - trig->subirq_base].enabled = false;
>> +}
>> +
>> +static void iio_trig_subirqunmask(struct irq_data *d)
>> +{
>> + struct irq_chip *chip = irq_data_get_irq_chip(d);
>> + struct iio_trigger *trig
>> + = container_of(chip,
>> + struct iio_trigger, subirq_chip);
>> + trig->subirqs[d->irq - trig->subirq_base].enabled = true;
>> +}
>> +
>> +struct iio_trigger *iio_allocate_trigger_named(const char *name)
>> {
>> struct iio_trigger *trig;
>> trig = kzalloc(sizeof *trig, GFP_KERNEL);
>> if (trig) {
>> + int i;
>> trig->dev.type = &iio_trig_type;
>> trig->dev.bus = &iio_bus_type;
>> device_initialize(&trig->dev);
>> @@ -357,10 +467,40 @@ struct iio_trigger *iio_allocate_trigger(void)
>> spin_lock_init(&trig->pollfunc_list_lock);
>> INIT_LIST_HEAD(&trig->list);
>> INIT_LIST_HEAD(&trig->pollfunc_list);
>> +
>> + if (name) {
>> + mutex_init(&trig->pool_lock);
>> + trig->subirq_base
>> + = iio_irq_pool_get_range(
>> + CONFIG_IIO_CONSUMERS_PER_TRIGGER);
>> + if (trig->subirq_base < 0) {
>> + kfree(trig);
>> + return NULL;
>> + }
>> + trig->name = name;
>> + trig->subirq_chip.name = name;
>> + trig->subirq_chip.irq_mask = &iio_trig_subirqmask;
>> + trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask;
>> + for (i = 0; i < CONFIG_IIO_CONSUMERS_PER_TRIGGER; i++) {
>> + irq_set_chip(trig->subirq_base + i,
>> + &trig->subirq_chip);
>> + irq_set_handler(trig->subirq_base + i,
>> + &handle_simple_irq);
>> + irq_modify_status(trig->subirq_base + i,
>> + IRQ_NOREQUEST | IRQ_NOAUTOEN,
>> + IRQ_NOPROBE);
>> + }
>> + }
>> iio_get();
>> }
>> return trig;
>> }
>> +EXPORT_SYMBOL(iio_allocate_trigger_named);
>> +
>> +struct iio_trigger *iio_allocate_trigger(void)
>> +{
>> + return iio_allocate_trigger_named(NULL);
>> +}
>> EXPORT_SYMBOL(iio_allocate_trigger);
>>
>> void iio_free_trigger(struct iio_trigger *trig)
>> diff --git a/drivers/staging/iio/trigger.h b/drivers/staging/iio/trigger.h
>> index c6ab32f..0c44c5e 100644
>> --- a/drivers/staging/iio/trigger.h
>> +++ b/drivers/staging/iio/trigger.h
>> @@ -6,9 +6,15 @@
>> * under the terms of the GNU General Public License version 2 as published by
>> * the Free Software Foundation.
>> */
>> +#include <linux/irq.h>
>> +
>> #ifndef _IIO_TRIGGER_H_
>> #define _IIO_TRIGGER_H_
>>
>> +struct iio_subirq {
>> + bool enabled;
>> +};
>> +
>> /**
>> * struct iio_trigger - industrial I/O trigger device
>> *
>> @@ -43,6 +49,13 @@ struct iio_trigger {
>>
>> int (*set_trigger_state)(struct iio_trigger *trig, bool state);
>> int (*try_reenable)(struct iio_trigger *trig);
>> +
>> + struct irq_chip subirq_chip;
>> + int subirq_base;
>> +
>> + struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
>> + unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
>> + struct mutex pool_lock;
>> };
>>
>> static inline struct iio_trigger *to_iio_trigger(struct device *d)
>> @@ -114,6 +127,27 @@ int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
>> void iio_trigger_poll(struct iio_trigger *trig, s64 time);
>> void iio_trigger_notify_done(struct iio_trigger *trig);
>>
>> +static inline int iio_trigger_get_irq(struct iio_trigger *trig)
>> +{
>> + int ret;
>> + mutex_lock(&trig->pool_lock);
>> + ret = bitmap_find_free_region(trig->pool,
>> + CONFIG_IIO_CONSUMERS_PER_TRIGGER,
>> + ilog2(1));
>> + mutex_unlock(&trig->pool_lock);
>> + if (ret >= 0)
>> + ret += trig->subirq_base;
>> +
>> + return ret;
>> +};
>> +
>> +static inline void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
>> +{
>> + mutex_lock(&trig->pool_lock);
>> + clear_bit(irq - trig->subirq_base, trig->pool);
>> + mutex_unlock(&trig->pool_lock);
>> +};
>> +
>> /**
>> * struct iio_poll_func - poll function pair
>> *
>> @@ -125,11 +159,14 @@ void iio_trigger_notify_done(struct iio_trigger *trig);
>> * @poll_func_main: function in here is run after all immediates.
>> * Reading from sensor etc typically involves
>> * scheduling from here.
>> - *
>> - * The two stage approach used here is only important when multiple sensors are
>> - * being triggered by a single trigger. This really comes into its own with
>> - * simultaneous sampling devices where a simple latch command can be used to
>> - * make the device store the values on all inputs.
>> + * @h: the function that is actually run on trigger
>> + * @thread: threaded interrupt part
>> + * @type: the type of interrupt (basically if oneshot)
>> + * @irq: the corresponding irq as allocated from the
>> + * trigger pool
>> + * @timestamp: some devices need a timestamp grabbed as soon
>> + * as possible after the trigger - hence handler
>> + * passes it via here.
>> **/
>> struct iio_poll_func {
>> struct list_head list;
>> @@ -137,12 +174,20 @@ struct iio_poll_func {
>> void (*poll_func_immediate)(struct iio_dev *indio_dev);
>> void (*poll_func_main)(struct iio_dev *private_data, s64 time);
>>
>> + irqreturn_t (*h)(int irq, void *p);
>> + irqreturn_t (*thread)(int irq, void *p);
>> + int type;
>> + char *name;
>> + int irq;
>> + s64 timestamp;
>> };
>>
>> int iio_alloc_pollfunc(struct iio_dev *indio_dev,
>> void (*immediate)(struct iio_dev *indio_dev),
>> void (*main)(struct iio_dev *private_data, s64 time));
>>
>> +irqreturn_t iio_pollfunc_store_time(int irq, void *p);
>> +
>> /*
>> * Two functions for common case where all that happens is a pollfunc
>> * is attached and detached from a trigger
>> @@ -151,7 +196,7 @@ int iio_triggered_ring_postenable(struct iio_dev *indio_dev);
>> int iio_triggered_ring_predisable(struct iio_dev *indio_dev);
>>
>> struct iio_trigger *iio_allocate_trigger(void);
>> -
>> +struct iio_trigger *iio_allocate_trigger_named(const char *name);
>> void iio_free_trigger(struct iio_trigger *trig);
>>
>> #endif /* _IIO_TRIGGER_H_ */
>
>
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