LXR linux/drivers/fsi/fsi-master.h

   1/*
   2 * FSI master definitions. These comprise the core <--> master interface,
   3 * to allow the core to interact with the (hardware-specific) masters.
   4 *
   5 * Copyright (C) IBM Corporation 2016
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 */
  16
  17#ifndef DRIVERS_FSI_MASTER_H
  18#define DRIVERS_FSI_MASTER_H
  19
  20#include <linux/device.h>
  21
  22#define FSI_MASTER_FLAG_SWCLOCK         0x1
  23
  24struct fsi_master {
  25        struct device   dev;
  26        int             idx;
  27        int             n_links;
  28        int             flags;
  29        int             (*read)(struct fsi_master *, int link, uint8_t id,
  30                                uint32_t addr, void *val, size_t size);
  31        int             (*write)(struct fsi_master *, int link, uint8_t id,
  32                                uint32_t addr, const void *val, size_t size);
  33        int             (*term)(struct fsi_master *, int link, uint8_t id);
  34        int             (*send_break)(struct fsi_master *, int link);
  35        int             (*link_enable)(struct fsi_master *, int link);
  36};
  37
  38#define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev)
  39
  40/**
  41 * fsi_master registration & lifetime: the fsi_master_register() and
  42 * fsi_master_unregister() functions will take ownership of the master, and
  43 * ->dev in particular. The registration path performs a get_device(), which
  44 * takes the first reference on the device. Similarly, the unregistration path
  45 * performs a put_device(), which may well drop the last reference.
  46 *
  47 * This means that master implementations *may* need to hold their own
  48 * reference (via get_device()) on master->dev. In particular, if the device's
  49 * ->release callback frees the fsi_master, then fsi_master_unregister will
  50 * invoke this free if no other reference is held.
  51 *
  52 * The same applies for the error path of fsi_master_register; if the call
  53 * fails, dev->release will have been invoked.
  54 */
  55extern int fsi_master_register(struct fsi_master *master);
  56extern void fsi_master_unregister(struct fsi_master *master);
  57
  58extern int fsi_master_rescan(struct fsi_master *master);
  59
  60#endif /* DRIVERS_FSI_MASTER_H */
  61