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 24 struct 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 */ 55 extern int fsi_master_register(struct fsi_master *master); 56 extern void fsi_master_unregister(struct fsi_master *master); 57 58 extern int fsi_master_rescan(struct fsi_master *master); 59 60 #endif /* DRIVERS_FSI_MASTER_H */ 61