Add a helper function for executing the common tasks which are usually involved in setting up a simple triggered buffer. It will allocate the buffer, allocate the pollfunc and register the buffer. Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx> --- drivers/iio/Kconfig | 7 ++ drivers/iio/Makefile | 1 + drivers/iio/industrialio-triggered-buffer.c | 109 +++++++++++++++++++++++++++ include/linux/iio/buffer.h | 7 ++ 4 files changed, 124 insertions(+) create mode 100644 drivers/iio/industrialio-triggered-buffer.c diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index 103349f..612073f 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -30,6 +30,13 @@ config IIO_KFIFO_BUF no buffer events so it is up to userspace to work out how often to read from the buffer. +config IIO_TRIGGERED_BUFFER + tristate + select IIO_TRIGGER + select IIO_KFIFO_BUF + help + Provides helper functions for setting up triggered buffers. + endif # IIO_BUFFER config IIO_TRIGGER diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index c38fa2a..34309ab 100644 --- a/drivers/iio/Makefile +++ b/drivers/iio/Makefile @@ -7,6 +7,7 @@ industrialio-y := industrialio-core.o industrialio-event.o inkern.o industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o +obj-$(CONFIG_IIO_TRIGGERED_BUFFER) += industrialio-triggered-buffer.o obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o obj-y += adc/ diff --git a/drivers/iio/industrialio-triggered-buffer.c b/drivers/iio/industrialio-triggered-buffer.c new file mode 100644 index 0000000..653ebe5 --- /dev/null +++ b/drivers/iio/industrialio-triggered-buffer.c @@ -0,0 +1,109 @@ + /* + * Copyright (c) 2012 Analog Devices, Inc. + * Author: Lars-Peter Clausen <lars@xxxxxxxxxx> + * + * 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/kernel.h> +#include <linux/export.h> +#include <linux/module.h> +#include <linux/iio/iio.h> +#include <linux/iio/buffer.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/kfifo_buf.h> + +static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { + .preenable = &iio_sw_buffer_preenable, + .postenable = &iio_triggered_buffer_postenable, + .predisable = &iio_triggered_buffer_predisable, +}; + +/** + * iio_triggered_buffer_setup() - Setup simple software ringbuffer and pollfunc + * @indio_dev: IIO device structure + * @pollfunc_bh: Function which will be used as pollfunc bottom half + * @pollfunc_th: Function which will be used as pollfunc top half + * @setup_ops: Buffer setup functions to use for this device. + * If NULL the default setup functions for triggered + * buffers will be used. + * + * This function combines some common tasks which will normally be performed + * when setting up a triggered buffer. It will allocate the buffer and the + * pollfunc, as well as register the buffer with IIO core. + * + * Before calling this function the indio_dev structure should already be + * completly initzialized but not yet registered. + * + * To free the resources allocated by this function + * iio_triggered_buffer_cleanup() should be called. + */ +int iio_triggered_buffer_setup(struct iio_dev *indio_dev, + irqreturn_t (*pollfunc_bh)(int irq, void *p), + irqreturn_t (*pollfunc_th)(int irq, void *p), + const struct iio_buffer_setup_ops *setup_ops) +{ + int ret; + + indio_dev->buffer = iio_kfifo_allocate(indio_dev); + if (!indio_dev->buffer) { + ret = -ENOMEM; + goto error_ret; + } + + indio_dev->pollfunc = iio_alloc_pollfunc(pollfunc_bh, + pollfunc_th, + IRQF_ONESHOT, + indio_dev, + "%s_consumer%d", + indio_dev->name, + indio_dev->id); + if (indio_dev->pollfunc == NULL) { + ret = -ENOMEM; + goto error_deallocate_sw_rb; + } + + /* Ring buffer functions - here trigger setup related */ + if (setup_ops) + indio_dev->setup_ops = setup_ops; + else + indio_dev->setup_ops = &iio_triggered_buffer_setup_ops; + + /* Flag that polled ring buffering is possible */ + indio_dev->modes |= INDIO_BUFFER_TRIGGERED; + + ret = iio_buffer_register(indio_dev, + indio_dev->channels, + indio_dev->num_channels); + if (ret) + goto error_dealloc_pollfunc; + + return 0; + +error_dealloc_pollfunc: + iio_dealloc_pollfunc(indio_dev->pollfunc); +error_deallocate_sw_rb: + iio_kfifo_free(indio_dev->buffer); +error_ret: + return ret; +} +EXPORT_SYMBOL(iio_triggered_buffer_setup); + +/** + * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup() + * @indio_dev: IIO device structure + */ +void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev) +{ + iio_buffer_unregister(indio_dev); + iio_dealloc_pollfunc(indio_dev->pollfunc); + iio_kfifo_free(indio_dev->buffer); +} +EXPORT_SYMBOL(iio_triggered_buffer_cleanup); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@xxxxxxxxxx>"); +MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index fb0fe46..1b3d3eb 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -10,6 +10,7 @@ #ifndef _IIO_BUFFER_GENERIC_H_ #define _IIO_BUFFER_GENERIC_H_ #include <linux/sysfs.h> +#include <linux/interrupt.h> #include <linux/iio/iio.h> #ifdef CONFIG_IIO_BUFFER @@ -174,6 +175,12 @@ ssize_t iio_buffer_show_enable(struct device *dev, int iio_sw_buffer_preenable(struct iio_dev *indio_dev); +int iio_triggered_buffer_setup(struct iio_dev *indio_dev, + irqreturn_t (*pollfunc_bh)(int irq, void *p), + irqreturn_t (*pollfunc_th)(int irq, void *p), + const struct iio_buffer_setup_ops *setup_ops); +void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev); + #else /* CONFIG_IIO_BUFFER */ static inline int iio_buffer_register(struct iio_dev *indio_dev, -- 1.7.10 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html