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 #define __TEGRA_IVC_H
   8
   9 #include <linux/device.h>
  10 #include <linux/dma-mapping.h>
  11 #include <linux/iosys-map.h>
  12 #include <linux/types.h>
  13
  14 struct tegra_ivc_header;
  15
  16 struct tegra_ivc {
  17         struct device *peer;
  18
  19         struct {
  20                 struct iosys_map map;
  21                 unsigned int position;
  22                 dma_addr_t phys;
  23         } rx, tx;
  24
  25         void (*notify)(struct tegra_ivc *ivc, void *data);
  26         void *notify_data;
  27
  28         unsigned int num_frames;
  29         size_t frame_size;
  30 };
  31
  32 /**
  33  * tegra_ivc_read_get_next_frame - Peek at the next frame to receive
  34  * @ivc         pointer of the IVC channel
  35  *
  36  * Peek at the next frame to be received, without removing it from
  37  * the queue.
  38  *
  39  * Returns a pointer to the frame, or an error encoded pointer.
  40  */
  41 int tegra_ivc_read_get_next_frame(struct tegra_ivc *ivc, struct iosys_map *map);
  42
  43 /**
  44  * tegra_ivc_read_advance - Advance the read queue
  45  * @ivc         pointer of the IVC channel
  46  *
  47  * Advance the read queue
  48  *
  49  * Returns 0, or a negative error value if failed.
  50  */
  51 int tegra_ivc_read_advance(struct tegra_ivc *ivc);
  52
  53 /**
  54  * tegra_ivc_write_get_next_frame - Poke at the next frame to transmit
  55  * @ivc         pointer of the IVC channel
  56  *
  57  * Get access to the next frame.
  58  *
  59  * Returns a pointer to the frame, or an error encoded pointer.
  60  */
  61 int tegra_ivc_write_get_next_frame(struct tegra_ivc *ivc, struct iosys_map *map);
  62
  63 /**
  64  * tegra_ivc_write_advance - Advance the write queue
  65  * @ivc         pointer of the IVC channel
  66  *
  67  * Advance the write queue
  68  *
  69  * Returns 0, or a negative error value if failed.
  70  */
  71 int tegra_ivc_write_advance(struct tegra_ivc *ivc);
  72
  73 /**
  74  * tegra_ivc_notified - handle internal messages
  75  * @ivc         pointer of the IVC channel
  76  *
  77  * This function must be called following every notification.
  78  *
  79  * Returns 0 if the channel is ready for communication, or -EAGAIN if a channel
  80  * reset is in progress.
  81  */
  82 int tegra_ivc_notified(struct tegra_ivc *ivc);
  83
  84 /**
  85  * tegra_ivc_reset - initiates a reset of the shared memory state
  86  * @ivc         pointer of the IVC channel
  87  *
  88  * This function must be called after a channel is reserved before it is used
  89  * for communication. The channel will be ready for use when a subsequent call
  90  * to notify the remote of the channel reset.
  91  */
  92 void tegra_ivc_reset(struct tegra_ivc *ivc);
  93
  94 size_t tegra_ivc_align(size_t size);
  95 unsigned tegra_ivc_total_queue_size(unsigned queue_size);
  96 int tegra_ivc_init(struct tegra_ivc *ivc, struct device *peer, const struct iosys_map *rx,
  97                    dma_addr_t rx_phys, const struct iosys_map *tx, dma_addr_t tx_phys,
  98                    unsigned int num_frames, size_t frame_size,
  99                    void (*notify)(struct tegra_ivc *ivc, void *data),
 100                    void *data);
 101 void tegra_ivc_cleanup(struct tegra_ivc *ivc);
 102
 103 #endif /* __TEGRA_IVC_H */