1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * ipmi_si_sm.h 4 * 5 * State machine interface for low-level IPMI system management 6 * interface state machines. This code is the interface between 7 * the ipmi_smi code (that handles the policy of a KCS, SMIC, or 8 * BT interface) and the actual low-level state machine. 9 * 10 * Author: MontaVista Software, Inc. 11 * Corey Minyard <minyard@mvista.com> 12 * source@mvista.com 13 * 14 * Copyright 2002 MontaVista Software Inc. 15 */ 16 17 #ifndef __IPMI_SI_SM_H__ 18 #define __IPMI_SI_SM_H__ 19 20 #include "ipmi_si.h" 21 22 /* 23 * This is defined by the state machines themselves, it is an opaque 24 * data type for them to use. 25 */ 26 struct si_sm_data; 27 28 /* Results of SMI events. */ 29 enum si_sm_result { 30 SI_SM_CALL_WITHOUT_DELAY, /* Call the driver again immediately */ 31 SI_SM_CALL_WITH_DELAY, /* Delay some before calling again. */ 32 SI_SM_CALL_WITH_TICK_DELAY,/* Delay >=1 tick before calling again. */ 33 SI_SM_TRANSACTION_COMPLETE, /* A transaction is finished. */ 34 SI_SM_IDLE, /* The SM is in idle state. */ 35 SI_SM_HOSED, /* The hardware violated the state machine. */ 36 37 /* 38 * The hardware is asserting attn and the state machine is 39 * idle. 40 */ 41 SI_SM_ATTN 42 }; 43 44 /* Handlers for the SMI state machine. */ 45 struct si_sm_handlers { 46 /* 47 * Put the version number of the state machine here so the 48 * upper layer can print it. 49 */ 50 char *version; 51 52 /* 53 * Initialize the data and return the amount of I/O space to 54 * reserve for the space. 55 */ 56 unsigned int (*init_data)(struct si_sm_data *smi, 57 struct si_sm_io *io); 58 59 /* 60 * Start a new transaction in the state machine. This will 61 * return -2 if the state machine is not idle, -1 if the size 62 * is invalid (to large or too small), or 0 if the transaction 63 * is successfully completed. 64 */ 65 int (*start_transaction)(struct si_sm_data *smi, 66 unsigned char *data, unsigned int size); 67 68 /* 69 * Return the results after the transaction. This will return 70 * -1 if the buffer is too small, zero if no transaction is 71 * present, or the actual length of the result data. 72 */ 73 int (*get_result)(struct si_sm_data *smi, 74 unsigned char *data, unsigned int length); 75 76 /* 77 * Call this periodically (for a polled interface) or upon 78 * receiving an interrupt (for a interrupt-driven interface). 79 * If interrupt driven, you should probably poll this 80 * periodically when not in idle state. This should be called 81 * with the time that passed since the last call, if it is 82 * significant. Time is in microseconds. 83 */ 84 enum si_sm_result (*event)(struct si_sm_data *smi, long time); 85 86 /* 87 * Attempt to detect an SMI. Returns 0 on success or nonzero 88 * on failure. 89 */ 90 int (*detect)(struct si_sm_data *smi); 91 92 /* The interface is shutting down, so clean it up. */ 93 void (*cleanup)(struct si_sm_data *smi); 94 95 /* Return the size of the SMI structure in bytes. */ 96 int (*size)(void); 97 }; 98 99 /* Current state machines that we can use. */ 100 extern const struct si_sm_handlers kcs_smi_handlers; 101 extern const struct si_sm_handlers smic_smi_handlers; 102 extern const struct si_sm_handlers bt_smi_handlers; 103 104 #endif /* __IPMI_SI_SM_H__ */ 105