diff options
Diffstat (limited to 'include/linux/iio/buffer.h')
| -rw-r--r-- | include/linux/iio/buffer.h | 218 |
1 files changed, 52 insertions, 166 deletions
diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index 2bac0eb8948d..d37f82678f71 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -1,10 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* The industrial I/O core - generic buffer interfaces. * * Copyright (c) 2008 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. */ #ifndef _IIO_BUFFER_GENERIC_H_ @@ -12,185 +9,74 @@ #include <linux/sysfs.h> #include <linux/iio/iio.h> -#ifdef CONFIG_IIO_BUFFER - struct iio_buffer; -/** - * struct iio_buffer_access_funcs - access functions for buffers. - * @store_to: actually store stuff to the buffer - * @read_first_n: try to get a specified number of bytes (must exist) - * @request_update: if a parameter change has been marked, update underlying - * storage. - * @get_bytes_per_datum:get current bytes per datum - * @set_bytes_per_datum:set number of bytes per datum - * @get_length: get number of datums in buffer - * @set_length: set number of datums in buffer - * - * The purpose of this structure is to make the buffer element - * modular as event for a given driver, different usecases may require - * different buffer designs (space efficiency vs speed for example). - * - * It is worth noting that a given buffer implementation may only support a - * small proportion of these functions. The core code 'should' cope fine with - * any of them not existing. - **/ -struct iio_buffer_access_funcs { - int (*store_to)(struct iio_buffer *buffer, u8 *data); - int (*read_first_n)(struct iio_buffer *buffer, - size_t n, - char __user *buf); - - int (*request_update)(struct iio_buffer *buffer); - - int (*get_bytes_per_datum)(struct iio_buffer *buffer); - int (*set_bytes_per_datum)(struct iio_buffer *buffer, size_t bpd); - int (*get_length)(struct iio_buffer *buffer); - int (*set_length)(struct iio_buffer *buffer, int length); +enum iio_buffer_direction { + IIO_BUFFER_DIRECTION_IN, + IIO_BUFFER_DIRECTION_OUT, }; -/** - * struct iio_buffer - general buffer structure - * @length: [DEVICE] number of datums in buffer - * @bytes_per_datum: [DEVICE] size of individual datum including timestamp - * @scan_el_attrs: [DRIVER] control of scan elements if that scan mode - * control method is used - * @scan_mask: [INTERN] bitmask used in masking scan mode elements - * @scan_timestamp: [INTERN] does the scan mode include a timestamp - * @access: [DRIVER] buffer access functions associated with the - * implementation. - * @scan_el_dev_attr_list:[INTERN] list of scan element related attributes. - * @scan_el_group: [DRIVER] attribute group for those attributes not - * created from the iio_chan_info array. - * @pollq: [INTERN] wait queue to allow for polling on the buffer. - * @stufftoread: [INTERN] flag to indicate new data. - * @demux_list: [INTERN] list of operations required to demux the scan. - * @demux_bounce: [INTERN] buffer for doing gather from incoming scan. - * @buffer_list: [INTERN] entry in the devices list of current buffers. - */ -struct iio_buffer { - int length; - int bytes_per_datum; - struct attribute_group *scan_el_attrs; - long *scan_mask; - bool scan_timestamp; - const struct iio_buffer_access_funcs *access; - struct list_head scan_el_dev_attr_list; - struct attribute_group scan_el_group; - wait_queue_head_t pollq; - bool stufftoread; - const struct attribute_group *attrs; - struct list_head demux_list; - unsigned char *demux_bounce; - struct list_head buffer_list; -}; +int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data); + +int iio_pop_from_buffer(struct iio_buffer *buffer, void *data); /** - * iio_update_buffers() - add or remove buffer from active list - * @indio_dev: device to add buffer to - * @insert_buffer: buffer to insert - * @remove_buffer: buffer_to_remove + * iio_push_to_buffers_with_timestamp() - push data and timestamp to buffers + * @indio_dev: iio_dev structure for device. + * @data: sample data + * @timestamp: timestamp for the sample data + * + * DEPRECATED: Use iio_push_to_buffers_with_ts() instead. * - * Note this will tear down the all buffering and build it up again + * Returns 0 on success, a negative error code otherwise. */ -int iio_update_buffers(struct iio_dev *indio_dev, - struct iio_buffer *insert_buffer, - struct iio_buffer *remove_buffer); - -/** - * iio_buffer_init() - Initialize the buffer structure - * @buffer: buffer to be initialized - **/ -void iio_buffer_init(struct iio_buffer *buffer); - -int iio_scan_mask_query(struct iio_dev *indio_dev, - struct iio_buffer *buffer, int bit); +static inline int iio_push_to_buffers_with_timestamp(struct iio_dev *indio_dev, + void *data, int64_t timestamp) +{ + if (ACCESS_PRIVATE(indio_dev, scan_timestamp)) { + size_t ts_offset = indio_dev->scan_bytes / sizeof(int64_t) - 1; + ((int64_t *)data)[ts_offset] = timestamp; + } -/** - * iio_scan_mask_set() - set particular bit in the scan mask - * @indio_dev IIO device structure - * @buffer: the buffer whose scan mask we are interested in - * @bit: the bit to be set. - **/ -int iio_scan_mask_set(struct iio_dev *indio_dev, - struct iio_buffer *buffer, int bit); + return iio_push_to_buffers(indio_dev, data); +} /** - * iio_push_to_buffers() - push to a registered buffer. + * iio_push_to_buffers_with_ts() - push data and timestamp to buffers * @indio_dev: iio_dev structure for device. - * @data: Full scan. + * @data: Pointer to sample data buffer. + * @data_total_len: The size of @data in bytes. + * @timestamp: Timestamp for the sample data. + * + * Pushes data to the IIO device's buffers. If timestamps are enabled for the + * device the function will store the supplied timestamp as the last element in + * the sample data buffer before pushing it to the device buffers. The sample + * data buffer needs to be large enough to hold the additional timestamp + * (usually the buffer should be at least indio->scan_bytes bytes large). + * + * Context: Any context. + * Return: 0 on success, a negative error code otherwise. */ -int iio_push_to_buffers(struct iio_dev *indio_dev, unsigned char *data); - -int iio_update_demux(struct iio_dev *indio_dev); - -/** - * iio_buffer_register() - register the buffer with IIO core - * @indio_dev: device with the buffer to be registered - * @channels: the channel descriptions used to construct buffer - * @num_channels: the number of channels - **/ -int iio_buffer_register(struct iio_dev *indio_dev, - const struct iio_chan_spec *channels, - int num_channels); - -/** - * iio_buffer_unregister() - unregister the buffer from IIO core - * @indio_dev: the device with the buffer to be unregistered - **/ -void iio_buffer_unregister(struct iio_dev *indio_dev); - -/** - * iio_buffer_read_length() - attr func to get number of datums in the buffer - **/ -ssize_t iio_buffer_read_length(struct device *dev, - struct device_attribute *attr, - char *buf); -/** - * iio_buffer_write_length() - attr func to set number of datums in the buffer - **/ -ssize_t iio_buffer_write_length(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len); -/** - * iio_buffer_store_enable() - attr to turn the buffer on - **/ -ssize_t iio_buffer_store_enable(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t len); -/** - * iio_buffer_show_enable() - attr to see if the buffer is on - **/ -ssize_t iio_buffer_show_enable(struct device *dev, - struct device_attribute *attr, - char *buf); -#define IIO_BUFFER_LENGTH_ATTR DEVICE_ATTR(length, S_IRUGO | S_IWUSR, \ - iio_buffer_read_length, \ - iio_buffer_write_length) +static inline int iio_push_to_buffers_with_ts(struct iio_dev *indio_dev, + void *data, size_t data_total_len, + s64 timestamp) +{ + if (unlikely(data_total_len < indio_dev->scan_bytes)) { + dev_err(&indio_dev->dev, "Undersized storage pushed to buffer\n"); + return -ENOSPC; + } -#define IIO_BUFFER_ENABLE_ATTR DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, \ - iio_buffer_show_enable, \ - iio_buffer_store_enable) + return iio_push_to_buffers_with_timestamp(indio_dev, data, timestamp); +} -int iio_sw_buffer_preenable(struct iio_dev *indio_dev); +int iio_push_to_buffers_with_ts_unaligned(struct iio_dev *indio_dev, + const void *data, size_t data_sz, + int64_t timestamp); bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, - const unsigned long *mask); - -#else /* CONFIG_IIO_BUFFER */ - -static inline int iio_buffer_register(struct iio_dev *indio_dev, - const struct iio_chan_spec *channels, - int num_channels) -{ - return 0; -} - -static inline void iio_buffer_unregister(struct iio_dev *indio_dev) -{} + const unsigned long *mask); -#endif /* CONFIG_IIO_BUFFER */ +int iio_device_attach_buffer(struct iio_dev *indio_dev, + struct iio_buffer *buffer); #endif /* _IIO_BUFFER_GENERIC_H_ */ |