diff options
| -rw-r--r-- | drivers/iio/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/iio/Makefile | 1 | ||||
| -rw-r--r-- | drivers/iio/buffer_cb.c | 113 | ||||
| -rw-r--r-- | include/linux/iio/consumer.h | 46 |
4 files changed, 166 insertions, 0 deletions
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig index fc937aca71fb..65ae734c607d 100644 --- a/drivers/iio/Kconfig +++ b/drivers/iio/Kconfig @@ -20,6 +20,12 @@ config IIO_BUFFER if IIO_BUFFER +config IIO_BUFFER_CB +boolean "IIO callback buffer used for push in-kernel interfaces" + help + Should be selected by any drivers that do-inkernel push + usage. That is, those where the data is pushed to the consumer. + config IIO_KFIFO_BUF select IIO_TRIGGER tristate "Industrial I/O buffering based on kfifo" diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile index 761f2b65ac52..31d76a07ec65 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-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o +industrialio-$(CONFIG_IIO_BUFFER_CB) += buffer_cb.o obj-$(CONFIG_IIO_TRIGGERED_BUFFER) += industrialio-triggered-buffer.o obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o diff --git a/drivers/iio/buffer_cb.c b/drivers/iio/buffer_cb.c new file mode 100644 index 000000000000..4d40e24f3721 --- /dev/null +++ b/drivers/iio/buffer_cb.c @@ -0,0 +1,113 @@ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/iio/buffer.h> +#include <linux/iio/consumer.h> + +struct iio_cb_buffer { + struct iio_buffer buffer; + int (*cb)(u8 *data, void *private); + void *private; + struct iio_channel *channels; +}; + +static int iio_buffer_cb_store_to(struct iio_buffer *buffer, u8 *data) +{ + struct iio_cb_buffer *cb_buff = container_of(buffer, + struct iio_cb_buffer, + buffer); + + return cb_buff->cb(data, cb_buff->private); +} + +static struct iio_buffer_access_funcs iio_cb_access = { + .store_to = &iio_buffer_cb_store_to, +}; + +struct iio_cb_buffer *iio_channel_get_all_cb(const char *name, + int (*cb)(u8 *data, + void *private), + void *private) +{ + int ret; + struct iio_cb_buffer *cb_buff; + struct iio_dev *indio_dev; + struct iio_channel *chan; + + cb_buff = kzalloc(sizeof(*cb_buff), GFP_KERNEL); + if (cb_buff == NULL) { + ret = -ENOMEM; + goto error_ret; + } + + cb_buff->private = private; + cb_buff->cb = cb; + cb_buff->buffer.access = &iio_cb_access; + INIT_LIST_HEAD(&cb_buff->buffer.demux_list); + + cb_buff->channels = iio_channel_get_all(name); + if (IS_ERR(cb_buff->channels)) { + ret = PTR_ERR(cb_buff->channels); + goto error_free_cb_buff; + } + + indio_dev = cb_buff->channels[0].indio_dev; + cb_buff->buffer.scan_mask + = kcalloc(BITS_TO_LONGS(indio_dev->masklength), sizeof(long), + GFP_KERNEL); + if (cb_buff->buffer.scan_mask == NULL) { + ret = -ENOMEM; + goto error_release_channels; + } + chan = &cb_buff->channels[0]; + while (chan->indio_dev) { + if (chan->indio_dev != indio_dev) { + ret = -EINVAL; + goto error_release_channels; + } + set_bit(chan->channel->scan_index, + cb_buff->buffer.scan_mask); + chan++; + } + + return cb_buff; + +error_release_channels: + iio_channel_release_all(cb_buff->channels); +error_free_cb_buff: + kfree(cb_buff); +error_ret: + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(iio_channel_get_all_cb); + +int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff) +{ + return iio_update_buffers(cb_buff->channels[0].indio_dev, + &cb_buff->buffer, + NULL); +} +EXPORT_SYMBOL_GPL(iio_channel_start_all_cb); + +void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff) +{ + iio_update_buffers(cb_buff->channels[0].indio_dev, + NULL, + &cb_buff->buffer); +} +EXPORT_SYMBOL_GPL(iio_channel_stop_all_cb); + +void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buff) +{ + iio_channel_release_all(cb_buff->channels); + kfree(cb_buff); +} +EXPORT_SYMBOL_GPL(iio_channel_release_all_cb); + +struct iio_channel +*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer) +{ + return cb_buffer->channels; +} +EXPORT_SYMBOL_GPL(iio_channel_cb_get_channels); diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index 57efee63a6da..126c0a9375f2 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -61,6 +61,52 @@ struct iio_channel *iio_channel_get_all(const char *name); */ void iio_channel_release_all(struct iio_channel *chan); +struct iio_cb_buffer; +/** + * iio_channel_get_all_cb() - register callback for triggered capture + * @name: Name of client device. + * @cb: Callback function. + * @private: Private data passed to callback. + * + * NB right now we have no ability to mux data from multiple devices. + * So if the channels requested come from different devices this will + * fail. + */ +struct iio_cb_buffer *iio_channel_get_all_cb(const char *name, + int (*cb)(u8 *data, + void *private), + void *private); +/** + * iio_channel_release_all_cb() - release and unregister the callback. + * @cb_buffer: The callback buffer that was allocated. + */ +void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buffer); + +/** + * iio_channel_start_all_cb() - start the flow of data through callback. + * @cb_buff: The callback buffer we are starting. + */ +int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff); + +/** + * iio_channel_stop_all_cb() - stop the flow of data through the callback. + * @cb_buff: The callback buffer we are stopping. + */ +void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff); + +/** + * iio_channel_cb_get_channels() - get access to the underlying channels. + * @cb_buff: The callback buffer from whom we want the channel + * information. + * + * This function allows one to obtain information about the channels. + * Whilst this may allow direct reading if all buffers are disabled, the + * primary aim is to allow drivers that are consuming a channel to query + * things like scaling of the channel. + */ +struct iio_channel +*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer); + /** * iio_read_channel_raw() - read from a given channel * @chan: The channel being queried. |