From: Lars-Peter Clausen lars@metafoo.de
Hardware consumer's can be used when one IIO device has a direct connection to another device in hardware.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com --- V2 -> V3: Just Adding sign off. No update but Jonathan comment. Need to be taken into account (in agreement with Lars) when transforming rfc in patch. --- drivers/iio/Kconfig | 6 ++ drivers/iio/Makefile | 1 + drivers/iio/hw_consumer.c | 156 ++++++++++++++++++++++++++++++++++++++++ include/linux/iio/hw_consumer.h | 12 ++++ 4 files changed, 175 insertions(+) create mode 100644 drivers/iio/hw_consumer.c create mode 100644 include/linux/iio/hw_consumer.h
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index 6743b18..956dd18 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -30,6 +30,12 @@ config IIO_CONFIGFS (e.g. software triggers). For more info see Documentation/iio/iio_configfs.txt.
+config IIO_HW_CONSUMER + tristate + help + Hardware consumer buffer + + config IIO_TRIGGER bool "Enable triggered sampling support" help diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index 87e4c43..8472b97 100644 --- a/drivers/iio/Makefile +++ b/drivers/iio/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_IIO) += industrialio.o industrialio-y := industrialio-core.o industrialio-event.o inkern.o industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o +obj-$(CONFIG_IIO_HW_CONSUMER) += hw_consumer.o
obj-$(CONFIG_IIO_CONFIGFS) += industrialio-configfs.o obj-$(CONFIG_IIO_SW_DEVICE) += industrialio-sw-device.o diff --git a/drivers/iio/hw_consumer.c b/drivers/iio/hw_consumer.c new file mode 100644 index 0000000..66f0732 --- /dev/null +++ b/drivers/iio/hw_consumer.c @@ -0,0 +1,156 @@ +#include <linux/err.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/of.h> + +#include <linux/iio/iio.h> +#include "iio_core.h" +#include <linux/iio/machine.h> +#include <linux/iio/driver.h> +#include <linux/iio/consumer.h> +#include <linux/iio/hw_consumer.h> +#include <linux/iio/buffer.h> + +struct iio_hw_consumer { + struct list_head buffers; + struct iio_channel *channels; +}; + +struct hw_consumer_buffer { + struct list_head head; + struct iio_dev *indio_dev; + struct iio_buffer buffer; +}; + +static struct hw_consumer_buffer *iio_buffer_to_hw_consumer_buffer( + struct iio_buffer *buffer) +{ + return container_of(buffer, struct hw_consumer_buffer, buffer); +} + +static void iio_hw_buf_release(struct iio_buffer *buffer) +{ + struct hw_consumer_buffer *hw_buf = + iio_buffer_to_hw_consumer_buffer(buffer); + kfree(hw_buf->buffer.scan_mask); + kfree(hw_buf); +} + +static const struct iio_buffer_access_funcs iio_hw_buf_access = { + .release = &iio_hw_buf_release, + .modes = INDIO_BUFFER_HARDWARE, +}; + +static struct hw_consumer_buffer *iio_hw_consumer_get_buffer( + struct iio_hw_consumer *hwc, struct iio_dev *indio_dev) +{ + struct hw_consumer_buffer *buf; + + list_for_each_entry(buf, &hwc->buffers, head) { + if (buf->indio_dev == indio_dev) + return buf; + } + + buf = kzalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return NULL; + + buf->buffer.access = &iio_hw_buf_access; + buf->indio_dev = indio_dev; + buf->buffer.scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength), + sizeof(long), GFP_KERNEL); + if (!buf->buffer.scan_mask) + goto err_free_buf; + + iio_buffer_init(&buf->buffer); + list_add_tail(&buf->head, &hwc->buffers); + + return buf; + +err_free_buf: + kfree(buf); + return NULL; +} + +struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev) +{ + struct hw_consumer_buffer *buf; + struct iio_hw_consumer *hwc; + struct iio_channel *chan; + int ret; + + hwc = kzalloc(sizeof(*hwc), GFP_KERNEL); + if (!hwc) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&hwc->buffers); + + hwc->channels = iio_channel_get_all(dev); + if (IS_ERR(hwc->channels)) { + ret = PTR_ERR(hwc->channels); + goto err_free_hwc; + } + + chan = &hwc->channels[0]; + while (chan->indio_dev) { + buf = iio_hw_consumer_get_buffer(hwc, chan->indio_dev); + if (buf == NULL) { + ret = -ENOMEM; + goto err_put_buffers; + } + set_bit(chan->channel->scan_index, buf->buffer.scan_mask); + chan++; + } + + return hwc; + +err_put_buffers: + list_for_each_entry(buf, &hwc->buffers, head) + iio_buffer_put(&buf->buffer); + iio_channel_release_all(hwc->channels); +err_free_hwc: + kfree(hwc); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_alloc); + +void iio_hw_consumer_free(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf; + + iio_channel_release_all(hwc->channels); + list_for_each_entry(buf, &hwc->buffers, head) + iio_buffer_put(&buf->buffer); + kfree(hwc); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_free); + +int iio_hw_consumer_enable(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf; + int ret; + + list_for_each_entry(buf, &hwc->buffers, head) { + ret = iio_update_buffers(buf->indio_dev, &buf->buffer, NULL); + if (ret) + goto err_disable_buffers; + } + + return 0; + +err_disable_buffers: + list_for_each_entry_continue_reverse(buf, &hwc->buffers, head) + iio_update_buffers(buf->indio_dev, NULL, &buf->buffer); + return ret; +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_enable); + +void iio_hw_consumer_disable(struct iio_hw_consumer *hwc) +{ + struct hw_consumer_buffer *buf; + + list_for_each_entry(buf, &hwc->buffers, head) + iio_update_buffers(buf->indio_dev, NULL, &buf->buffer); +} +EXPORT_SYMBOL_GPL(iio_hw_consumer_disable); diff --git a/include/linux/iio/hw_consumer.h b/include/linux/iio/hw_consumer.h new file mode 100644 index 0000000..f12653d --- /dev/null +++ b/include/linux/iio/hw_consumer.h @@ -0,0 +1,12 @@ +#ifndef LINUX_IIO_HW_CONSUMER_BUFFER_H +#define LINUX_IIO_HW_CONSUMER_BUFFER_H + +struct device; +struct iio_hw_consumer; + +struct iio_hw_consumer *iio_hw_consumer_alloc(struct device *dev); +void iio_hw_consumer_free(struct iio_hw_consumer *hwc); +int iio_hw_consumer_enable(struct iio_hw_consumer *hwc); +void iio_hw_consumer_disable(struct iio_hw_consumer *hwc); + +#endif