LXR linux/include/linux/slimbus.h

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2011-2017, The Linux Foundation
   4 */
   5
   6#ifndef _LINUX_SLIMBUS_H
   7#define _LINUX_SLIMBUS_H
   8#include <linux/device.h>
   9#include <linux/module.h>
  10#include <linux/completion.h>
  11#include <linux/mod_devicetable.h>
  12
  13extern struct bus_type slimbus_bus;
  14
  15/**
  16 * struct slim_eaddr - Enumeration address for a SLIMbus device
  17 * @manf_id: Manufacturer Id for the device
  18 * @prod_code: Product code
  19 * @dev_index: Device index
  20 * @instance: Instance value
  21 */
  22struct slim_eaddr {
  23        u16 manf_id;
  24        u16 prod_code;
  25        u8 dev_index;
  26        u8 instance;
  27} __packed;
  28
  29/**
  30 * enum slim_device_status - slim device status
  31 * @SLIM_DEVICE_STATUS_DOWN: Slim device is absent or not reported yet.
  32 * @SLIM_DEVICE_STATUS_UP: Slim device is announced on the bus.
  33 * @SLIM_DEVICE_STATUS_RESERVED: Reserved for future use.
  34 */
  35enum slim_device_status {
  36        SLIM_DEVICE_STATUS_DOWN = 0,
  37        SLIM_DEVICE_STATUS_UP,
  38        SLIM_DEVICE_STATUS_RESERVED,
  39};
  40
  41struct slim_controller;
  42
  43/**
  44 * struct slim_device - Slim device handle.
  45 * @dev: Driver model representation of the device.
  46 * @e_addr: Enumeration address of this device.
  47 * @status: slim device status
  48 * @ctrl: slim controller instance.
  49 * @laddr: 1-byte Logical address of this device.
  50 * @is_laddr_valid: indicates if the laddr is valid or not
  51 *
  52 * This is the client/device handle returned when a SLIMbus
  53 * device is registered with a controller.
  54 * Pointer to this structure is used by client-driver as a handle.
  55 */
  56struct slim_device {
  57        struct device           dev;
  58        struct slim_eaddr       e_addr;
  59        struct slim_controller  *ctrl;
  60        enum slim_device_status status;
  61        u8                      laddr;
  62        bool                    is_laddr_valid;
  63};
  64
  65#define to_slim_device(d) container_of(d, struct slim_device, dev)
  66
  67/**
  68 * struct slim_driver - SLIMbus 'generic device' (slave) device driver
  69 *                              (similar to 'spi_device' on SPI)
  70 * @probe: Binds this driver to a SLIMbus device.
  71 * @remove: Unbinds this driver from the SLIMbus device.
  72 * @shutdown: Standard shutdown callback used during powerdown/halt.
  73 * @device_status: This callback is called when
  74 *      - The device reports present and gets a laddr assigned
  75 *      - The device reports absent, or the bus goes down.
  76 * @driver: SLIMbus device drivers should initialize name and owner field of
  77 *          this structure
  78 * @id_table: List of SLIMbus devices supported by this driver
  79 */
  80
  81struct slim_driver {
  82        int     (*probe)(struct slim_device *sl);
  83        void    (*remove)(struct slim_device *sl);
  84        void    (*shutdown)(struct slim_device *sl);
  85        int     (*device_status)(struct slim_device *sl,
  86                                 enum slim_device_status s);
  87        struct device_driver            driver;
  88        const struct slim_device_id     *id_table;
  89};
  90#define to_slim_driver(d) container_of(d, struct slim_driver, driver)
  91
  92/**
  93 * struct slim_val_inf - Slimbus value or information element
  94 * @start_offset: Specifies starting offset in information/value element map
  95 * @rbuf: buffer to read the values
  96 * @wbuf: buffer to write
  97 * @num_bytes: upto 16. This ensures that the message will fit the slicesize
  98 *              per SLIMbus spec
  99 * @comp: completion for asynchronous operations, valid only if TID is
 100 *        required for transaction, like REQUEST operations.
 101 *        Rest of the transactions are synchronous anyway.
 102 */
 103struct slim_val_inf {
 104        u16                     start_offset;
 105        u8                      num_bytes;
 106        u8                      *rbuf;
 107        const u8                *wbuf;
 108        struct  completion      *comp;
 109};
 110
 111/*
 112 * use a macro to avoid include chaining to get THIS_MODULE
 113 */
 114#define slim_driver_register(drv) \
 115        __slim_driver_register(drv, THIS_MODULE)
 116int __slim_driver_register(struct slim_driver *drv, struct module *owner);
 117void slim_driver_unregister(struct slim_driver *drv);
 118
 119/**
 120 * module_slim_driver() - Helper macro for registering a SLIMbus driver
 121 * @__slim_driver: slimbus_driver struct
 122 *
 123 * Helper macro for SLIMbus drivers which do not do anything special in module
 124 * init/exit. This eliminates a lot of boilerplate. Each module may only
 125 * use this macro once, and calling it replaces module_init() and module_exit()
 126 */
 127#define module_slim_driver(__slim_driver) \
 128        module_driver(__slim_driver, slim_driver_register, \
 129                        slim_driver_unregister)
 130
 131static inline void *slim_get_devicedata(const struct slim_device *dev)
 132{
 133        return dev_get_drvdata(&dev->dev);
 134}
 135
 136static inline void slim_set_devicedata(struct slim_device *dev, void *data)
 137{
 138        dev_set_drvdata(&dev->dev, data);
 139}
 140
 141struct slim_device *slim_get_device(struct slim_controller *ctrl,
 142                                    struct slim_eaddr *e_addr);
 143int slim_get_logical_addr(struct slim_device *sbdev);
 144
 145/* Information Element management messages */
 146#define SLIM_MSG_MC_REQUEST_INFORMATION          0x20
 147#define SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION    0x21
 148#define SLIM_MSG_MC_REPLY_INFORMATION            0x24
 149#define SLIM_MSG_MC_CLEAR_INFORMATION            0x28
 150#define SLIM_MSG_MC_REPORT_INFORMATION           0x29
 151
 152/* Value Element management messages */
 153#define SLIM_MSG_MC_REQUEST_VALUE                0x60
 154#define SLIM_MSG_MC_REQUEST_CHANGE_VALUE         0x61
 155#define SLIM_MSG_MC_REPLY_VALUE                  0x64
 156#define SLIM_MSG_MC_CHANGE_VALUE                 0x68
 157
 158int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
 159                  u8 mc);
 160int slim_readb(struct slim_device *sdev, u32 addr);
 161int slim_writeb(struct slim_device *sdev, u32 addr, u8 value);
 162int slim_read(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 163int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 164#endif /* _LINUX_SLIMBUS_H */
 165