/*
   * Copyright © 2014 Red Hat.
   *
   * Permission to use, copy, modify, distribute, and sell this software and its
   * documentation for any purpose is hereby granted without fee, provided that
   * the above copyright notice appear in all copies and that both that copyright
   * notice and this permission notice appear in supporting documentation, and
   * that the name of the copyright holders not be used in advertising or
   * publicity pertaining to distribution of the software without specific,
   * written prior permission.  The copyright holders make no representations
   * about the suitability of this software for any purpose.  It is provided "as
   * is" without express or implied warranty.
   *
   * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
   * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
   * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
   * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
   * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
   * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
   * OF THIS SOFTWARE.
   */
  #ifndef _DRM_DP_MST_HELPER_H_
  #define _DRM_DP_MST_HELPER_H_
  
  #include <linux/types.h>
  #include <drm/drm_dp_helper.h>
  
  struct drm_dp_mst_branch;
  
  /**

   * struct drm_dp_vcpi - Virtual Channel Payload Identifier

   * @vcpi: Virtual channel ID.
   * @pbn: Payload Bandwidth Number for this channel
   * @aligned_pbn: PBN aligned with slot size
   * @num_slots: number of slots for this PBN
   */
  struct drm_dp_vcpi {
  	int vcpi;
  	int pbn;
  	int aligned_pbn;
  	int num_slots;
  };
  
  /**
   * struct drm_dp_mst_port - MST port
   * @kref: reference count for this port.

   * @port_num: port number
   * @input: if this port is an input port.
   * @mcs: message capability status - DP 1.2 spec.
   * @ddps: DisplayPort Device Plug Status - DP 1.2
   * @pdt: Peer Device Type
   * @ldps: Legacy Device Plug Status
   * @dpcd_rev: DPCD revision of device on this port
   * @num_sdp_streams: Number of simultaneous streams
   * @num_sdp_stream_sinks: Number of stream sinks
   * @available_pbn: Available bandwidth for this port.
   * @next: link to next port on this branch device
   * @mstb: branch device attach below this port
   * @aux: i2c aux transport to talk to device connected to this port.
   * @parent: branch device parent of this port
   * @vcpi: Virtual Channel Payload info for this port.
   * @connector: DRM connector this port is connected to.
   * @mgr: topology manager this port lives under.
   *
   * This structure represents an MST port endpoint on a device somewhere
   * in the MST topology.
   */
  struct drm_dp_mst_port {
  	struct kref kref;

  	u8 port_num;
  	bool input;
  	bool mcs;
  	bool ddps;
  	u8 pdt;
  	bool ldps;
  	u8 dpcd_rev;
  	u8 num_sdp_streams;
  	u8 num_sdp_stream_sinks;
  	uint16_t available_pbn;
  	struct list_head next;
  	struct drm_dp_mst_branch *mstb; /* pointer to an mstb if this port has one */
  	struct drm_dp_aux aux; /* i2c bus for this port? */
  	struct drm_dp_mst_branch *parent;
  
  	struct drm_dp_vcpi vcpi;
  	struct drm_connector *connector;
  	struct drm_dp_mst_topology_mgr *mgr;

  	/**
  	 * @cached_edid: for DP logical ports - make tiling work by ensuring
  	 * that the EDID for all connectors is read immediately.
  	 */
  	struct edid *cached_edid;
  	/**
  	 * @has_audio: Tracks whether the sink connector to this port is
  	 * audio-capable.
  	 */

  	bool has_audio;

  };
  
  /**
   * struct drm_dp_mst_branch - MST branch device.
   * @kref: reference count for this port.
   * @rad: Relative Address to talk to this branch device.
   * @lct: Link count total to talk to this branch device.
   * @num_ports: number of ports on the branch.
   * @msg_slots: one bit per transmitted msg slot.
   * @ports: linked list of ports on this branch.
   * @port_parent: pointer to the port parent, NULL if toplevel.
   * @mgr: topology manager for this branch device.
   * @tx_slots: transmission slots for this device.
   * @last_seqno: last sequence number used to talk to this.
   * @link_address_sent: if a link address message has been sent to this device yet.

   * @guid: guid for DP 1.2 branch device. port under this branch can be
   * identified by port #.

   *
   * This structure represents an MST branch device, there is one

   * primary branch device at the root, along with any other branches connected
   * to downstream port of parent branches.

   */
  struct drm_dp_mst_branch {
  	struct kref kref;
  	u8 rad[8];
  	u8 lct;
  	int num_ports;
  
  	int msg_slots;
  	struct list_head ports;
  
  	/* list of tx ops queue for this port */
  	struct drm_dp_mst_port *port_parent;
  	struct drm_dp_mst_topology_mgr *mgr;
  
  	/* slots are protected by mstb->mgr->qlock */
  	struct drm_dp_sideband_msg_tx *tx_slots[2];
  	int last_seqno;
  	bool link_address_sent;

  
  	/* global unique identifier to identify branch devices */
  	u8 guid[16];

  };
  
  
  /* sideband msg header - not bit struct */
  struct drm_dp_sideband_msg_hdr {
  	u8 lct;
  	u8 lcr;
  	u8 rad[8];
  	bool broadcast;
  	bool path_msg;
  	u8 msg_len;
  	bool somt;
  	bool eomt;
  	bool seqno;
  };
  
  struct drm_dp_nak_reply {
  	u8 guid[16];
  	u8 reason;
  	u8 nak_data;
  };
  
  struct drm_dp_link_address_ack_reply {
  	u8 guid[16];
  	u8 nports;
  	struct drm_dp_link_addr_reply_port {
  		bool input_port;
  		u8 peer_device_type;
  		u8 port_number;
  		bool mcs;
  		bool ddps;
  		bool legacy_device_plug_status;
  		u8 dpcd_revision;
  		u8 peer_guid[16];
  		u8 num_sdp_streams;
  		u8 num_sdp_stream_sinks;
  	} ports[16];
  };
  
  struct drm_dp_remote_dpcd_read_ack_reply {
  	u8 port_number;
  	u8 num_bytes;
  	u8 bytes[255];
  };
  
  struct drm_dp_remote_dpcd_write_ack_reply {
  	u8 port_number;
  };
  
  struct drm_dp_remote_dpcd_write_nak_reply {
  	u8 port_number;
  	u8 reason;
  	u8 bytes_written_before_failure;
  };
  
  struct drm_dp_remote_i2c_read_ack_reply {
  	u8 port_number;
  	u8 num_bytes;
  	u8 bytes[255];
  };
  
  struct drm_dp_remote_i2c_read_nak_reply {
  	u8 port_number;
  	u8 nak_reason;
  	u8 i2c_nak_transaction;
  };
  
  struct drm_dp_remote_i2c_write_ack_reply {
  	u8 port_number;
  };
  
  
  struct drm_dp_sideband_msg_rx {
  	u8 chunk[48];
  	u8 msg[256];
  	u8 curchunk_len;
  	u8 curchunk_idx; /* chunk we are parsing now */
  	u8 curchunk_hdrlen;
  	u8 curlen; /* total length of the msg */
  	bool have_somt;
  	bool have_eomt;
  	struct drm_dp_sideband_msg_hdr initial_hdr;
  };

  #define DRM_DP_MAX_SDP_STREAMS 16

  struct drm_dp_allocate_payload {
  	u8 port_number;
  	u8 number_sdp_streams;
  	u8 vcpi;
  	u16 pbn;

  	u8 sdp_stream_sink[DRM_DP_MAX_SDP_STREAMS];

  };
  
  struct drm_dp_allocate_payload_ack_reply {
  	u8 port_number;
  	u8 vcpi;
  	u16 allocated_pbn;
  };
  
  struct drm_dp_connection_status_notify {
  	u8 guid[16];
  	u8 port_number;
  	bool legacy_device_plug_status;
  	bool displayport_device_plug_status;
  	bool message_capability_status;
  	bool input_port;
  	u8 peer_device_type;
  };
  
  struct drm_dp_remote_dpcd_read {
  	u8 port_number;
  	u32 dpcd_address;
  	u8 num_bytes;
  };
  
  struct drm_dp_remote_dpcd_write {
  	u8 port_number;
  	u32 dpcd_address;
  	u8 num_bytes;
  	u8 *bytes;
  };

  #define DP_REMOTE_I2C_READ_MAX_TRANSACTIONS 4

  struct drm_dp_remote_i2c_read {
  	u8 num_transactions;
  	u8 port_number;
  	struct {
  		u8 i2c_dev_id;
  		u8 num_bytes;
  		u8 *bytes;
  		u8 no_stop_bit;
  		u8 i2c_transaction_delay;

  	} transactions[DP_REMOTE_I2C_READ_MAX_TRANSACTIONS];

  	u8 read_i2c_device_id;
  	u8 num_bytes_read;
  };
  
  struct drm_dp_remote_i2c_write {
  	u8 port_number;
  	u8 write_i2c_device_id;
  	u8 num_bytes;
  	u8 *bytes;
  };
  
  /* this covers ENUM_RESOURCES, POWER_DOWN_PHY, POWER_UP_PHY */
  struct drm_dp_port_number_req {
  	u8 port_number;
  };
  
  struct drm_dp_enum_path_resources_ack_reply {
  	u8 port_number;
  	u16 full_payload_bw_number;
  	u16 avail_payload_bw_number;
  };
  
  /* covers POWER_DOWN_PHY, POWER_UP_PHY */
  struct drm_dp_port_number_rep {
  	u8 port_number;
  };
  
  struct drm_dp_query_payload {
  	u8 port_number;
  	u8 vcpi;
  };
  
  struct drm_dp_resource_status_notify {
  	u8 port_number;
  	u8 guid[16];
  	u16 available_pbn;
  };
  
  struct drm_dp_query_payload_ack_reply {
  	u8 port_number;
  	u8 allocated_pbn;
  };
  
  struct drm_dp_sideband_msg_req_body {
  	u8 req_type;
  	union ack_req {
  		struct drm_dp_connection_status_notify conn_stat;
  		struct drm_dp_port_number_req port_num;
  		struct drm_dp_resource_status_notify resource_stat;
  
  		struct drm_dp_query_payload query_payload;
  		struct drm_dp_allocate_payload allocate_payload;
  
  		struct drm_dp_remote_dpcd_read dpcd_read;
  		struct drm_dp_remote_dpcd_write dpcd_write;
  
  		struct drm_dp_remote_i2c_read i2c_read;
  		struct drm_dp_remote_i2c_write i2c_write;
  	} u;
  };
  
  struct drm_dp_sideband_msg_reply_body {
  	u8 reply_type;
  	u8 req_type;
  	union ack_replies {
  		struct drm_dp_nak_reply nak;
  		struct drm_dp_link_address_ack_reply link_addr;
  		struct drm_dp_port_number_rep port_number;
  
  		struct drm_dp_enum_path_resources_ack_reply path_resources;
  		struct drm_dp_allocate_payload_ack_reply allocate_payload;
  		struct drm_dp_query_payload_ack_reply query_payload;
  
  		struct drm_dp_remote_dpcd_read_ack_reply remote_dpcd_read_ack;
  		struct drm_dp_remote_dpcd_write_ack_reply remote_dpcd_write_ack;
  		struct drm_dp_remote_dpcd_write_nak_reply remote_dpcd_write_nack;
  
  		struct drm_dp_remote_i2c_read_ack_reply remote_i2c_read_ack;
  		struct drm_dp_remote_i2c_read_nak_reply remote_i2c_read_nack;
  		struct drm_dp_remote_i2c_write_ack_reply remote_i2c_write_ack;
  	} u;
  };
  
  /* msg is queued to be put into a slot */
  #define DRM_DP_SIDEBAND_TX_QUEUED 0
  /* msg has started transmitting on a slot - still on msgq */
  #define DRM_DP_SIDEBAND_TX_START_SEND 1
  /* msg has finished transmitting on a slot - removed from msgq only in slot */
  #define DRM_DP_SIDEBAND_TX_SENT 2
  /* msg has received a response - removed from slot */
  #define DRM_DP_SIDEBAND_TX_RX 3
  #define DRM_DP_SIDEBAND_TX_TIMEOUT 4
  
  struct drm_dp_sideband_msg_tx {
  	u8 msg[256];
  	u8 chunk[48];
  	u8 cur_offset;
  	u8 cur_len;
  	struct drm_dp_mst_branch *dst;
  	struct list_head next;
  	int seqno;
  	int state;
  	bool path_msg;
  	struct drm_dp_sideband_msg_reply_body reply;
  };
  
  /* sideband msg handler */
  struct drm_dp_mst_topology_mgr;
  struct drm_dp_mst_topology_cbs {
  	/* create a connector for a port */

  	struct drm_connector *(*add_connector)(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, const char *path);

  	void (*register_connector)(struct drm_connector *connector);

  	void (*destroy_connector)(struct drm_dp_mst_topology_mgr *mgr,
  				  struct drm_connector *connector);
  	void (*hotplug)(struct drm_dp_mst_topology_mgr *mgr);
  
  };
  
  #define DP_MAX_PAYLOAD (sizeof(unsigned long) * 8)
  
  #define DP_PAYLOAD_LOCAL 1
  #define DP_PAYLOAD_REMOTE 2
  #define DP_PAYLOAD_DELETE_LOCAL 3
  
  struct drm_dp_payload {
  	int payload_state;
  	int start_slot;
  	int num_slots;

  	int vcpi;

  };
  
  /**
   * struct drm_dp_mst_topology_mgr - DisplayPort MST manager

   *
   * This struct represents the toplevel displayport MST topology manager.
   * There should be one instance of this for every MST capable DP connector
   * on the GPU.
   */
  struct drm_dp_mst_topology_mgr {

  	/**
  	 * @dev: device pointer for adding i2c devices etc.
  	 */

  	struct device *dev;

  	/**
  	 * @cbs: callbacks for connector addition and destruction.
  	 */

  	const struct drm_dp_mst_topology_cbs *cbs;

  	/**
  	 * @max_dpcd_transaction_bytes: maximum number of bytes to read/write
  	 * in one go.
  	 */

  	int max_dpcd_transaction_bytes;

  	/**
  	 * @aux: AUX channel for the DP MST connector this topolgy mgr is
  	 * controlling.
  	 */
  	struct drm_dp_aux *aux;
  	/**
  	 * @max_payloads: maximum number of payloads the GPU can generate.
  	 */

  	int max_payloads;

  	/**
  	 * @conn_base_id: DRM connector ID this mgr is connected to. Only used
  	 * to build the MST connector path value.
  	 */

  	int conn_base_id;

  	/**
  	 * @down_rep_recv: Message receiver state for down replies. This and
  	 * @up_req_recv are only ever access from the work item, which is
  	 * serialised.
  	 */

  	struct drm_dp_sideband_msg_rx down_rep_recv;

  	/**
  	 * @up_req_recv: Message receiver state for up requests. This and
  	 * @down_rep_recv are only ever access from the work item, which is
  	 * serialised.
  	 */

  	struct drm_dp_sideband_msg_rx up_req_recv;

  	/**
  	 * @lock: protects mst state, primary, dpcd.
  	 */
  	struct mutex lock;

  	/**
  	 * @mst_state: If this manager is enabled for an MST capable port. False
  	 * if no MST sink/branch devices is connected.
  	 */

  	bool mst_state;

  	/**
  	 * @mst_primary: Pointer to the primary/first branch device.
  	 */

  	struct drm_dp_mst_branch *mst_primary;

  	/**
  	 * @dpcd: Cache of DPCD for primary port.
  	 */

  	u8 dpcd[DP_RECEIVER_CAP_SIZE];

  	/**
  	 * @sink_count: Sink count from DEVICE_SERVICE_IRQ_VECTOR_ESI0.
  	 */

  	u8 sink_count;

  	/**
  	 * @pbn_div: PBN to slots divisor.
  	 */

  	int pbn_div;

  	/**
  	 * @total_slots: Total slots that can be allocated.
  	 */

  	int total_slots;

  	/**
  	 * @avail_slots: Still available slots that can be allocated.
  	 */

  	int avail_slots;

  	/**
  	 * @total_pbn: Total PBN count.
  	 */

  	int total_pbn;

  	/**
  	 * @qlock: protects @tx_msg_downq, the tx_slots in struct
  	 * &drm_dp_mst_branch and txmsg->state once they are queued
  	 */

  	struct mutex qlock;

  	/**
  	 * @tx_msg_downq: List of pending down replies.
  	 */

  	struct list_head tx_msg_downq;

  	/**
  	 * @payload_lock: Protect payload information.
  	 */

  	struct mutex payload_lock;

  	/**
  	 * @proposed_vcpis: Array of pointers for the new VCPI allocation. The
  	 * VCPI structure itself is embedded into the corresponding
  	 * &drm_dp_mst_port structure.
  	 */

  	struct drm_dp_vcpi **proposed_vcpis;

  	/**
  	 * @payloads: Array of payloads.
  	 */

  	struct drm_dp_payload *payloads;

  	/**
  	 * @payload_mask: Elements of @payloads actually in use. Since
  	 * reallocation of active outputs isn't possible gaps can be created by
  	 * disabling outputs out of order compared to how they've been enabled.
  	 */

  	unsigned long payload_mask;

  	/**
  	 * @vcpi_mask: Similar to @payload_mask, but for @proposed_vcpis.
  	 */

  	unsigned long vcpi_mask;

  	/**
  	 * @tx_waitq: Wait to queue stall for the tx worker.
  	 */

  	wait_queue_head_t tx_waitq;

  	/**
  	 * @work: Probe work.
  	 */

  	struct work_struct work;

  	/**
  	 * @tx_work: Sideband transmit worker. This can nest within the main
  	 * @work worker for each transaction @work launches.
  	 */

  	struct work_struct tx_work;

  	/**
  	 * @destroy_connector_list: List of to be destroyed connectors.
  	 */

  	struct list_head destroy_connector_list;

  	/**
  	 * @destroy_connector_lock: Protects @connector_list.
  	 */

  	struct mutex destroy_connector_lock;

  	/**
  	 * @destroy_connector_work: Work item to destroy connectors. Needed to
  	 * avoid locking inversion.
  	 */

  	struct work_struct destroy_connector_work;

  };
  
  int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, struct device *dev, struct drm_dp_aux *aux, int max_dpcd_transaction_bytes, int max_payloads, int conn_base_id);
  
  void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr);
  
  
  int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state);
  
  
  int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled);

  enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);

  bool drm_dp_mst_port_has_audio(struct drm_dp_mst_topology_mgr *mgr,
  					struct drm_dp_mst_port *port);

  struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
  
  
  int drm_dp_calc_pbn_mode(int clock, int bpp);
  
  
  bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots);

  int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);

  
  void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port);
  
  
  void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
  				struct drm_dp_mst_port *port);
  
  
  int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr,
  			   int pbn);
  
  
  int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr);
  
  
  int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr);
  
  int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr);
  
  void drm_dp_mst_dump_topology(struct seq_file *m,
  			      struct drm_dp_mst_topology_mgr *mgr);
  
  void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr);
  int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr);
  #endif