1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * FSI master definitions. These comprise the core <--> master interface, 4 * to allow the core to interact with the (hardware-specific) masters. 5 * 6 * Copyright (C) IBM Corporation 2016 7 */ 8 9 #ifndef DRIVERS_FSI_MASTER_H 10 #define DRIVERS_FSI_MASTER_H 11 12 #include <linux/device.h> 13 #include <linux/mutex.h> 14 15 /* Various protocol delays */ 16 #define FSI_ECHO_DELAY_CLOCKS 16 /* Number clocks for echo delay */ 17 #define FSI_SEND_DELAY_CLOCKS 16 /* Number clocks for send delay */ 18 #define FSI_PRE_BREAK_CLOCKS 50 /* Number clocks to prep for break */ 19 #define FSI_BREAK_CLOCKS 256 /* Number of clocks to issue break */ 20 #define FSI_POST_BREAK_CLOCKS 16000 /* Number clocks to set up cfam */ 21 #define FSI_INIT_CLOCKS 5000 /* Clock out any old data */ 22 #define FSI_MASTER_DPOLL_CLOCKS 50 /* < 21 will cause slave to hang */ 23 #define FSI_MASTER_EPOLL_CLOCKS 50 /* Number of clocks for E_POLL retry */ 24 25 /* Various retry maximums */ 26 #define FSI_CRC_ERR_RETRIES 10 27 #define FSI_MASTER_MAX_BUSY 200 28 #define FSI_MASTER_MTOE_COUNT 1000 29 30 /* Command encodings */ 31 #define FSI_CMD_DPOLL 0x2 32 #define FSI_CMD_EPOLL 0x3 33 #define FSI_CMD_TERM 0x3f 34 #define FSI_CMD_ABS_AR 0x4 35 #define FSI_CMD_REL_AR 0x5 36 #define FSI_CMD_SAME_AR 0x3 /* but only a 2-bit opcode... */ 37 38 /* Slave responses */ 39 #define FSI_RESP_ACK 0 /* Success */ 40 #define FSI_RESP_BUSY 1 /* Slave busy */ 41 #define FSI_RESP_ERRA 2 /* Any (misc) Error */ 42 #define FSI_RESP_ERRC 3 /* Slave reports master CRC error */ 43 44 /* Misc */ 45 #define FSI_CRC_SIZE 4 46 47 /* fsi-master definition and flags */ 48 #define FSI_MASTER_FLAG_SWCLOCK 0x1 49 50 struct fsi_master { 51 struct device dev; 52 int idx; 53 int n_links; 54 int flags; 55 struct mutex scan_lock; 56 int (*read)(struct fsi_master *, int link, uint8_t id, 57 uint32_t addr, void *val, size_t size); 58 int (*write)(struct fsi_master *, int link, uint8_t id, 59 uint32_t addr, const void *val, size_t size); 60 int (*term)(struct fsi_master *, int link, uint8_t id); 61 int (*send_break)(struct fsi_master *, int link); 62 int (*link_enable)(struct fsi_master *, int link); 63 int (*link_config)(struct fsi_master *, int link, 64 u8 t_send_delay, u8 t_echo_delay); 65 }; 66 67 #define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev) 68 69 /** 70 * fsi_master registration & lifetime: the fsi_master_register() and 71 * fsi_master_unregister() functions will take ownership of the master, and 72 * ->dev in particular. The registration path performs a get_device(), which 73 * takes the first reference on the device. Similarly, the unregistration path 74 * performs a put_device(), which may well drop the last reference. 75 * 76 * This means that master implementations *may* need to hold their own 77 * reference (via get_device()) on master->dev. In particular, if the device's 78 * ->release callback frees the fsi_master, then fsi_master_unregister will 79 * invoke this free if no other reference is held. 80 * 81 * The same applies for the error path of fsi_master_register; if the call 82 * fails, dev->release will have been invoked. 83 */ 84 extern int fsi_master_register(struct fsi_master *master); 85 extern void fsi_master_unregister(struct fsi_master *master); 86 87 extern int fsi_master_rescan(struct fsi_master *master); 88 89 #endif /* DRIVERS_FSI_MASTER_H */ 90
