1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (c) 2015-2018, Intel Corporation.
  4 */
  5
  6#ifndef __KCS_BMC_H__
  7#define __KCS_BMC_H__
  8
  9#include <linux/miscdevice.h>
 10
 11/* Different phases of the KCS BMC module.
 12 *  KCS_PHASE_IDLE:
 13 *            BMC should not be expecting nor sending any data.
 14 *  KCS_PHASE_WRITE_START:
 15 *            BMC is receiving a WRITE_START command from system software.
 16 *  KCS_PHASE_WRITE_DATA:
 17 *            BMC is receiving a data byte from system software.
 18 *  KCS_PHASE_WRITE_END_CMD:
 19 *            BMC is waiting a last data byte from system software.
 20 *  KCS_PHASE_WRITE_DONE:
 21 *            BMC has received the whole request from system software.
 22 *  KCS_PHASE_WAIT_READ:
 23 *            BMC is waiting the response from the upper IPMI service.
 24 *  KCS_PHASE_READ:
 25 *            BMC is transferring the response to system software.
 26 *  KCS_PHASE_ABORT_ERROR1:
 27 *            BMC is waiting error status request from system software.
 28 *  KCS_PHASE_ABORT_ERROR2:
 29 *            BMC is waiting for idle status afer error from system software.
 30 *  KCS_PHASE_ERROR:
 31 *            BMC has detected a protocol violation at the interface level.
 32 */
 33enum kcs_phases {
 34	KCS_PHASE_IDLE,
 35
 36	KCS_PHASE_WRITE_START,
 37	KCS_PHASE_WRITE_DATA,
 38	KCS_PHASE_WRITE_END_CMD,
 39	KCS_PHASE_WRITE_DONE,
 40
 41	KCS_PHASE_WAIT_READ,
 42	KCS_PHASE_READ,
 43
 44	KCS_PHASE_ABORT_ERROR1,
 45	KCS_PHASE_ABORT_ERROR2,
 46	KCS_PHASE_ERROR
 47};
 48
 49/* IPMI 2.0 - Table 9-4, KCS Interface Status Codes */
 50enum kcs_errors {
 51	KCS_NO_ERROR                = 0x00,
 52	KCS_ABORTED_BY_COMMAND      = 0x01,
 53	KCS_ILLEGAL_CONTROL_CODE    = 0x02,
 54	KCS_LENGTH_ERROR            = 0x06,
 55	KCS_UNSPECIFIED_ERROR       = 0xFF
 56};
 57
 58/* IPMI 2.0 - 9.5, KCS Interface Registers
 59 * @idr: Input Data Register
 60 * @odr: Output Data Register
 61 * @str: Status Register
 62 */
 63struct kcs_ioreg {
 64	u32 idr;
 65	u32 odr;
 66	u32 str;
 67};
 68
 69struct kcs_bmc {
 70	spinlock_t lock;
 71
 72	u32 channel;
 73	int running;
 74
 75	/* Setup by BMC KCS controller driver */
 76	struct kcs_ioreg ioreg;
 77	u8 (*io_inputb)(struct kcs_bmc *kcs_bmc, u32 reg);
 78	void (*io_outputb)(struct kcs_bmc *kcs_bmc, u32 reg, u8 b);
 79
 80	enum kcs_phases phase;
 81	enum kcs_errors error;
 82
 83	wait_queue_head_t queue;
 84	bool data_in_avail;
 85	int  data_in_idx;
 86	u8  *data_in;
 87
 88	int  data_out_idx;
 89	int  data_out_len;
 90	u8  *data_out;
 91
 92	struct mutex mutex;
 93	u8 *kbuffer;
 94
 95	struct miscdevice miscdev;
 96
 97	unsigned long priv[];
 98};
 99
100static inline void *kcs_bmc_priv(struct kcs_bmc *kcs_bmc)
101{
102	return kcs_bmc->priv;
103}
104
105int kcs_bmc_handle_event(struct kcs_bmc *kcs_bmc);
106struct kcs_bmc *kcs_bmc_alloc(struct device *dev, int sizeof_priv,
107					u32 channel);
108#endif /* __KCS_BMC_H__ */