From: Lars-Peter Clausen <lars@xxxxxxxxxx>
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@xxxxxxxxxx>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
---
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
--
1.9.1
--
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