include/soc/tegra/ivc.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
   4  */
   5
   6 #ifndef __TEGRA_IVC_H
   7
   8 #include <linux/device.h>
   9 #include <linux/dma-mapping.h>
  10 #include <linux/types.h>
  11
  12 struct tegra_ivc_header;
  13
  14 struct tegra_ivc {
  15         struct device *peer;
  16
  17         struct {
  18                 struct tegra_ivc_header *channel;
  19                 unsigned int position;
  20                 dma_addr_t phys;
  21         } rx, tx;
  22
  23         void (*notify)(struct tegra_ivc *ivc, void *data);
  24         void *notify_data;
  25
  26         unsigned int num_frames;
  27         size_t frame_size;
  28 };
  29
  30 /**
  31  * tegra_ivc_read_get_next_frame - Peek at the next frame to receive
  32  * @ivc         pointer of the IVC channel
  33  *
  34  * Peek at the next frame to be received, without removing it from
  35  * the queue.
  36  *
  37  * Returns a pointer to the frame, or an error encoded pointer.
  38  */
  39 void *tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc);
  40
  41 /**
  42  * tegra_ivc_read_advance - Advance the read queue
  43  * @ivc         pointer of the IVC channel
  44  *
  45  * Advance the read queue
  46  *
  47  * Returns 0, or a negative error value if failed.
  48  */
  49 int tegra_ivc_read_advance(struct tegra_ivc *ivc);
  50
  51 /**
  52  * tegra_ivc_write_get_next_frame - Poke at the next frame to transmit
  53  * @ivc         pointer of the IVC channel
  54  *
  55  * Get access to the next frame.
  56  *
  57  * Returns a pointer to the frame, or an error encoded pointer.
  58  */
  59 void *tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc);
  60
  61 /**
  62  * tegra_ivc_write_advance - Advance the write queue
  63  * @ivc         pointer of the IVC channel
  64  *
  65  * Advance the write queue
  66  *
  67  * Returns 0, or a negative error value if failed.
  68  */
  69 int tegra_ivc_write_advance(struct tegra_ivc *ivc);
  70
  71 /**
  72  * tegra_ivc_notified - handle internal messages
  73  * @ivc         pointer of the IVC channel
  74  *
  75  * This function must be called following every notification.
  76  *
  77  * Returns 0 if the channel is ready for communication, or -EAGAIN if a channel
  78  * reset is in progress.
  79  */
  80 int tegra_ivc_notified(struct tegra_ivc *ivc);
  81
  82 /**
  83  * tegra_ivc_reset - initiates a reset of the shared memory state
  84  * @ivc         pointer of the IVC channel
  85  *
  86  * This function must be called after a channel is reserved before it is used
  87  * for communication. The channel will be ready for use when a subsequent call
  88  * to notify the remote of the channel reset.
  89  */
  90 void tegra_ivc_reset(struct tegra_ivc *ivc);
  91
  92 size_t tegra_ivc_align(size_t size);
  93 unsigned tegra_ivc_total_queue_size(unsigned queue_size);
  94 int tegra_ivc_init(struct tegra_ivc *ivc, struct device *peer, void *rx,
  95                    dma_addr_t rx_phys, void *tx, dma_addr_t tx_phys,
  96                    unsigned int num_frames, size_t frame_size,
  97                    void (*notify)(struct tegra_ivc *ivc, void *data),
  98                    void *data);
  99 void tegra_ivc_cleanup(struct tegra_ivc *ivc);
 100
 101 #endif /* __TEGRA_IVC_H */