/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. */ #ifndef __TEGRA_IVC_H #include <linux/device.h> #include <linux/dma-mapping.h> #include <linux/types.h> struct tegra_ivc_header; struct tegra_ivc { struct device *peer; struct { struct tegra_ivc_header *channel; unsigned int position; dma_addr_t phys; } rx, tx; void (*notify)(struct tegra_ivc *ivc, void *data); void *notify_data; unsigned int num_frames; size_t frame_size; }; /** * tegra_ivc_read_get_next_frame - Peek at the next frame to receive * @ivc pointer of the IVC channel * * Peek at the next frame to be received, without removing it from * the queue. * * Returns a pointer to the frame, or an error encoded pointer. */ void *tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc); /** * tegra_ivc_read_advance - Advance the read queue * @ivc pointer of the IVC channel * * Advance the read queue * * Returns 0, or a negative error value if failed. */ int tegra_ivc_read_advance(struct tegra_ivc *ivc); /** * tegra_ivc_write_get_next_frame - Poke at the next frame to transmit * @ivc pointer of the IVC channel * * Get access to the next frame. * * Returns a pointer to the frame, or an error encoded pointer. */ void *tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc); /** * tegra_ivc_write_advance - Advance the write queue * @ivc pointer of the IVC channel * * Advance the write queue * * Returns 0, or a negative error value if failed. */ int tegra_ivc_write_advance(struct tegra_ivc *ivc); /** * tegra_ivc_notified - handle internal messages * @ivc pointer of the IVC channel * * This function must be called following every notification. * * Returns 0 if the channel is ready for communication, or -EAGAIN if a channel * reset is in progress. */ int tegra_ivc_notified(struct tegra_ivc *ivc); /** * tegra_ivc_reset - initiates a reset of the shared memory state * @ivc pointer of the IVC channel * * This function must be called after a channel is reserved before it is used * for communication. The channel will be ready for use when a subsequent call * to notify the remote of the channel reset. */ void tegra_ivc_reset(struct tegra_ivc *ivc); size_t tegra_ivc_align(size_t size); unsigned tegra_ivc_total_queue_size(unsigned queue_size); int tegra_ivc_init(struct tegra_ivc *ivc, struct device *peer, void *rx, dma_addr_t rx_phys, void *tx, dma_addr_t tx_phys, unsigned int num_frames, size_t frame_size, void (*notify)(struct tegra_ivc *ivc, void *data), void *data); void tegra_ivc_cleanup(struct tegra_ivc *ivc); #endif /* __TEGRA_IVC_H */ |