LXR linux/include/soc/tegra/ivc.h

   1/*
   2 * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms and conditions of the GNU General Public License,
   6 * version 2, as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope it will be useful, but WITHOUT
   9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11 * more details.
  12 */
  13
  14#ifndef __TEGRA_IVC_H
  15
  16#include <linux/device.h>
  17#include <linux/dma-mapping.h>
  18#include <linux/types.h>
  19
  20struct tegra_ivc_header;
  21
  22struct tegra_ivc {
  23        struct device *peer;
  24
  25        struct {
  26                struct tegra_ivc_header *channel;
  27                unsigned int position;
  28                dma_addr_t phys;
  29        } rx, tx;
  30
  31        void (*notify)(struct tegra_ivc *ivc, void *data);
  32        void *notify_data;
  33
  34        unsigned int num_frames;
  35        size_t frame_size;
  36};
  37
  38/**
  39 * tegra_ivc_read_get_next_frame - Peek at the next frame to receive
  40 * @ivc         pointer of the IVC channel
  41 *
  42 * Peek at the next frame to be received, without removing it from
  43 * the queue.
  44 *
  45 * Returns a pointer to the frame, or an error encoded pointer.
  46 */
  47void *tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc);
  48
  49/**
  50 * tegra_ivc_read_advance - Advance the read queue
  51 * @ivc         pointer of the IVC channel
  52 *
  53 * Advance the read queue
  54 *
  55 * Returns 0, or a negative error value if failed.
  56 */
  57int tegra_ivc_read_advance(struct tegra_ivc *ivc);
  58
  59/**
  60 * tegra_ivc_write_get_next_frame - Poke at the next frame to transmit
  61 * @ivc         pointer of the IVC channel
  62 *
  63 * Get access to the next frame.
  64 *
  65 * Returns a pointer to the frame, or an error encoded pointer.
  66 */
  67void *tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc);
  68
  69/**
  70 * tegra_ivc_write_advance - Advance the write queue
  71 * @ivc         pointer of the IVC channel
  72 *
  73 * Advance the write queue
  74 *
  75 * Returns 0, or a negative error value if failed.
  76 */
  77int tegra_ivc_write_advance(struct tegra_ivc *ivc);
  78
  79/**
  80 * tegra_ivc_notified - handle internal messages
  81 * @ivc         pointer of the IVC channel
  82 *
  83 * This function must be called following every notification.
  84 *
  85 * Returns 0 if the channel is ready for communication, or -EAGAIN if a channel
  86 * reset is in progress.
  87 */
  88int tegra_ivc_notified(struct tegra_ivc *ivc);
  89
  90/**
  91 * tegra_ivc_reset - initiates a reset of the shared memory state
  92 * @ivc         pointer of the IVC channel
  93 *
  94 * This function must be called after a channel is reserved before it is used
  95 * for communication. The channel will be ready for use when a subsequent call
  96 * to notify the remote of the channel reset.
  97 */
  98void tegra_ivc_reset(struct tegra_ivc *ivc);
  99
 100size_t tegra_ivc_align(size_t size);
 101unsigned tegra_ivc_total_queue_size(unsigned queue_size);
 102int tegra_ivc_init(struct tegra_ivc *ivc, struct device *peer, void *rx,
 103                   dma_addr_t rx_phys, void *tx, dma_addr_t tx_phys,
 104                   unsigned int num_frames, size_t frame_size,
 105                   void (*notify)(struct tegra_ivc *ivc, void *data),
 106                   void *data);
 107void tegra_ivc_cleanup(struct tegra_ivc *ivc);
 108
 109#endif /* __TEGRA_IVC_H */
 110