https://github.com/torvalds/linux
Tip revision: 1048ba83fb1c00cd24172e23e8263972f6b5d9ac authored by Linus Torvalds on 31 January 2021, 21:50:09 UTC
Linux 5.11-rc6
Linux 5.11-rc6
Tip revision: 1048ba8
most.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* most.h - API for component and adapter drivers
*
* Copyright (C) 2013-2015, Microchip Technology Germany II GmbH & Co. KG
*/
#ifndef __MOST_CORE_H__
#define __MOST_CORE_H__
#include <linux/types.h>
#include <linux/device.h>
struct module;
struct interface_private;
/**
* Interface type
*/
enum most_interface_type {
ITYPE_LOOPBACK = 1,
ITYPE_I2C,
ITYPE_I2S,
ITYPE_TSI,
ITYPE_HBI,
ITYPE_MEDIALB_DIM,
ITYPE_MEDIALB_DIM2,
ITYPE_USB,
ITYPE_PCIE
};
/**
* Channel direction.
*/
enum most_channel_direction {
MOST_CH_RX = 1 << 0,
MOST_CH_TX = 1 << 1,
};
/**
* Channel data type.
*/
enum most_channel_data_type {
MOST_CH_CONTROL = 1 << 0,
MOST_CH_ASYNC = 1 << 1,
MOST_CH_ISOC = 1 << 2,
MOST_CH_SYNC = 1 << 5,
};
enum most_status_flags {
/* MBO was processed successfully (data was send or received )*/
MBO_SUCCESS = 0,
/* The MBO contains wrong or missing information. */
MBO_E_INVAL,
/* MBO was completed as HDM Channel will be closed */
MBO_E_CLOSE,
};
/**
* struct most_channel_capability - Channel capability
* @direction: Supported channel directions.
* The value is bitwise OR-combination of the values from the
* enumeration most_channel_direction. Zero is allowed value and means
* "channel may not be used".
* @data_type: Supported channel data types.
* The value is bitwise OR-combination of the values from the
* enumeration most_channel_data_type. Zero is allowed value and means
* "channel may not be used".
* @num_buffers_packet: Maximum number of buffers supported by this channel
* for packet data types (Async,Control,QoS)
* @buffer_size_packet: Maximum buffer size supported by this channel
* for packet data types (Async,Control,QoS)
* @num_buffers_streaming: Maximum number of buffers supported by this channel
* for streaming data types (Sync,AV Packetized)
* @buffer_size_streaming: Maximum buffer size supported by this channel
* for streaming data types (Sync,AV Packetized)
* @name_suffix: Optional suffix providean by an HDM that is attached to the
* regular channel name.
*
* Describes the capabilities of a MOST channel like supported Data Types
* and directions. This information is provided by an HDM for the MostCore.
*
* The Core creates read only sysfs attribute files in
* /sys/devices/most/mdev#/<channel>/ with the
* following attributes:
* -available_directions
* -available_datatypes
* -number_of_packet_buffers
* -number_of_stream_buffers
* -size_of_packet_buffer
* -size_of_stream_buffer
* where content of each file is a string with all supported properties of this
* very channel attribute.
*/
struct most_channel_capability {
u16 direction;
u16 data_type;
u16 num_buffers_packet;
u16 buffer_size_packet;
u16 num_buffers_streaming;
u16 buffer_size_streaming;
const char *name_suffix;
};
/**
* struct most_channel_config - stores channel configuration
* @direction: direction of the channel
* @data_type: data type travelling over this channel
* @num_buffers: number of buffers
* @buffer_size: size of a buffer for AIM.
* Buffer size may be cutted down by HDM in a configure callback
* to match to a given interface and channel type.
* @extra_len: additional buffer space for internal HDM purposes like padding.
* May be set by HDM in a configure callback if needed.
* @subbuffer_size: size of a subbuffer
* @packets_per_xact: number of MOST frames that are packet inside one USB
* packet. This is USB specific
*
* Describes the configuration for a MOST channel. This information is
* provided from the MostCore to a HDM (like the Medusa PCIe Interface) as a
* parameter of the "configure" function call.
*/
struct most_channel_config {
enum most_channel_direction direction;
enum most_channel_data_type data_type;
u16 num_buffers;
u16 buffer_size;
u16 extra_len;
u16 subbuffer_size;
u16 packets_per_xact;
u16 dbr_size;
};
/*
* struct mbo - MOST Buffer Object.
* @context: context for core completion handler
* @priv: private data for HDM
*
* public: documented fields that are used for the communications
* between MostCore and HDMs
*
* @list: list head for use by the mbo's current owner
* @ifp: (in) associated interface instance
* @num_buffers_ptr: amount of pool buffers
* @hdm_channel_id: (in) HDM channel instance
* @virt_address: (in) kernel virtual address of the buffer
* @bus_address: (in) bus address of the buffer
* @buffer_length: (in) buffer payload length
* @processed_length: (out) processed length
* @status: (out) transfer status
* @complete: (in) completion routine
*
* The core allocates and initializes the MBO.
*
* The HDM receives MBO for transfer from the core with the call to enqueue().
* The HDM copies the data to- or from the buffer depending on configured
* channel direction, set "processed_length" and "status" and completes
* the transfer procedure by calling the completion routine.
*
* Finally, the MBO is being deallocated or recycled for further
* transfers of the same or a different HDM.
*
* Directions of usage:
* The core driver should never access any MBO fields (even if marked
* as "public") while the MBO is owned by an HDM. The ownership starts with
* the call of enqueue() and ends with the call of its complete() routine.
*
* II.
* Every HDM attached to the core driver _must_ ensure that it returns any MBO
* it owns (due to a previous call to enqueue() by the core driver) before it
* de-registers an interface or gets unloaded from the kernel. If this direction
* is violated memory leaks will occur, since the core driver does _not_ track
* MBOs it is currently not in control of.
*
*/
struct mbo {
void *context;
void *priv;
struct list_head list;
struct most_interface *ifp;
int *num_buffers_ptr;
u16 hdm_channel_id;
void *virt_address;
dma_addr_t bus_address;
u16 buffer_length;
u16 processed_length;
enum most_status_flags status;
void (*complete)(struct mbo *mbo);
};
/**
* Interface instance description.
*
* Describes an interface of a MOST device the core driver is bound to.
* This structure is allocated and initialized in the HDM. MostCore may not
* modify this structure.
*
* @dev: the actual device
* @mod: module
* @interface Interface type. \sa most_interface_type.
* @description PRELIMINARY.
* Unique description of the device instance from point of view of the
* interface in free text form (ASCII).
* It may be a hexadecimal presentation of the memory address for the MediaLB
* IP or USB device ID with USB properties for USB interface, etc.
* @num_channels Number of channels and size of the channel_vector.
* @channel_vector Properties of the channels.
* Array index represents channel ID by the driver.
* @configure Callback to change data type for the channel of the
* interface instance. May be zero if the instance of the interface is not
* configurable. Parameter channel_config describes direction and data
* type for the channel, configured by the higher level. The content of
* @enqueue Delivers MBO to the HDM for processing.
* After HDM completes Rx- or Tx- operation the processed MBO shall
* be returned back to the MostCore using completion routine.
* The reason to get the MBO delivered from the MostCore after the channel
* is poisoned is the re-opening of the channel by the application.
* In this case the HDM shall hold MBOs and service the channel as usual.
* The HDM must be able to hold at least one MBO for each channel.
* The callback returns a negative value on error, otherwise 0.
* @poison_channel Informs HDM about closing the channel. The HDM shall
* cancel all transfers and synchronously or asynchronously return
* all enqueued for this channel MBOs using the completion routine.
* The callback returns a negative value on error, otherwise 0.
* @request_netinfo: triggers retrieving of network info from the HDM by
* means of "Message exchange over MDP/MEP"
* The call of the function request_netinfo with the parameter on_netinfo as
* NULL prohibits use of the previously obtained function pointer.
* @priv Private field used by mostcore to store context information.
*/
struct most_interface {
struct device *dev;
struct device *driver_dev;
struct module *mod;
enum most_interface_type interface;
const char *description;
unsigned int num_channels;
struct most_channel_capability *channel_vector;
void *(*dma_alloc)(struct mbo *mbo, u32 size);
void (*dma_free)(struct mbo *mbo, u32 size);
int (*configure)(struct most_interface *iface, int channel_idx,
struct most_channel_config *channel_config);
int (*enqueue)(struct most_interface *iface, int channel_idx,
struct mbo *mbo);
int (*poison_channel)(struct most_interface *iface, int channel_idx);
void (*request_netinfo)(struct most_interface *iface, int channel_idx,
void (*on_netinfo)(struct most_interface *iface,
unsigned char link_stat,
unsigned char *mac_addr));
void *priv;
struct interface_private *p;
};
/**
* struct most_component - identifies a loadable component for the mostcore
* @list: list_head
* @name: component name
* @probe_channel: function for core to notify driver about channel connection
* @disconnect_channel: callback function to disconnect a certain channel
* @rx_completion: completion handler for received packets
* @tx_completion: completion handler for transmitted packets
*/
struct most_component {
struct list_head list;
const char *name;
struct module *mod;
int (*probe_channel)(struct most_interface *iface, int channel_idx,
struct most_channel_config *cfg, char *name,
char *param);
int (*disconnect_channel)(struct most_interface *iface,
int channel_idx);
int (*rx_completion)(struct mbo *mbo);
int (*tx_completion)(struct most_interface *iface, int channel_idx);
int (*cfg_complete)(void);
};
/**
* most_register_interface - Registers instance of the interface.
* @iface: Pointer to the interface instance description.
*
* Returns a pointer to the kobject of the generated instance.
*
* Note: HDM has to ensure that any reference held on the kobj is
* released before deregistering the interface.
*/
int most_register_interface(struct most_interface *iface);
/**
* Deregisters instance of the interface.
* @intf_instance Pointer to the interface instance description.
*/
void most_deregister_interface(struct most_interface *iface);
void most_submit_mbo(struct mbo *mbo);
/**
* most_stop_enqueue - prevents core from enqueing MBOs
* @iface: pointer to interface
* @channel_idx: channel index
*/
void most_stop_enqueue(struct most_interface *iface, int channel_idx);
/**
* most_resume_enqueue - allow core to enqueue MBOs again
* @iface: pointer to interface
* @channel_idx: channel index
*
* This clears the enqueue halt flag and enqueues all MBOs currently
* in wait fifo.
*/
void most_resume_enqueue(struct most_interface *iface, int channel_idx);
int most_register_component(struct most_component *comp);
int most_deregister_component(struct most_component *comp);
struct mbo *most_get_mbo(struct most_interface *iface, int channel_idx,
struct most_component *comp);
void most_put_mbo(struct mbo *mbo);
int channel_has_mbo(struct most_interface *iface, int channel_idx,
struct most_component *comp);
int most_start_channel(struct most_interface *iface, int channel_idx,
struct most_component *comp);
int most_stop_channel(struct most_interface *iface, int channel_idx,
struct most_component *comp);
int __init configfs_init(void);
int most_register_configfs_subsys(struct most_component *comp);
void most_deregister_configfs_subsys(struct most_component *comp);
int most_add_link(char *mdev, char *mdev_ch, char *comp_name, char *link_name,
char *comp_param);
int most_remove_link(char *mdev, char *mdev_ch, char *comp_name);
int most_set_cfg_buffer_size(char *mdev, char *mdev_ch, u16 val);
int most_set_cfg_subbuffer_size(char *mdev, char *mdev_ch, u16 val);
int most_set_cfg_dbr_size(char *mdev, char *mdev_ch, u16 val);
int most_set_cfg_num_buffers(char *mdev, char *mdev_ch, u16 val);
int most_set_cfg_datatype(char *mdev, char *mdev_ch, char *buf);
int most_set_cfg_direction(char *mdev, char *mdev_ch, char *buf);
int most_set_cfg_packets_xact(char *mdev, char *mdev_ch, u16 val);
int most_cfg_complete(char *comp_name);
void most_interface_register_notify(const char *mdev_name);
#endif /* MOST_CORE_H_ */