1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _HVSI_H
3#define _HVSI_H
4
5#define VS_DATA_PACKET_HEADER           0xff
6#define VS_CONTROL_PACKET_HEADER        0xfe
7#define VS_QUERY_PACKET_HEADER          0xfd
8#define VS_QUERY_RESPONSE_PACKET_HEADER 0xfc
9
10/* control verbs */
11#define VSV_SET_MODEM_CTL    1 /* to service processor only */
12#define VSV_MODEM_CTL_UPDATE 2 /* from service processor only */
13#define VSV_CLOSE_PROTOCOL   3
14
15/* query verbs */
16#define VSV_SEND_VERSION_NUMBER 1
17#define VSV_SEND_MODEM_CTL_STATUS 2
18
19/* yes, these masks are not consecutive. */
20#define HVSI_TSDTR 0x01
21#define HVSI_TSCD  0x20
22
23#define HVSI_MAX_OUTGOING_DATA 12
24#define HVSI_VERSION 1
25
26struct hvsi_header {
27	uint8_t  type;
28	uint8_t  len;
29	__be16 seqno;
30} __attribute__((packed));
31
32struct hvsi_data {
33	struct hvsi_header hdr;
34	uint8_t  data[HVSI_MAX_OUTGOING_DATA];
35} __attribute__((packed));
36
37struct hvsi_control {
38	struct hvsi_header hdr;
39	__be16 verb;
40	/* optional depending on verb: */
41	__be32 word;
42	__be32 mask;
43} __attribute__((packed));
44
45struct hvsi_query {
46	struct hvsi_header hdr;
47	__be16 verb;
48} __attribute__((packed));
49
50struct hvsi_query_response {
51	struct hvsi_header hdr;
52	__be16 verb;
53	__be16 query_seqno;
54	union {
55		uint8_t  version;
56		__be32 mctrl_word;
57	} u;
58} __attribute__((packed));
59
60/* hvsi lib struct definitions */
61#define HVSI_INBUF_SIZE		255
62struct tty_struct;
63struct hvsi_priv {
64	unsigned int	inbuf_len;	/* data in input buffer */
65	unsigned char	inbuf[HVSI_INBUF_SIZE];
66	unsigned int	inbuf_cur;	/* Cursor in input buffer */
67	size_t		inbuf_pktlen;	/* packet length from cursor */
68	atomic_t	seqno;		/* packet sequence number */
69	unsigned int	opened:1;	/* driver opened */
70	unsigned int	established:1;	/* protocol established */
71	unsigned int 	is_console:1;	/* used as a kernel console device */
72	unsigned int	mctrl_update:1;	/* modem control updated */
73	unsigned short	mctrl;		/* modem control */
74	struct tty_struct *tty;		/* tty structure */
75	ssize_t (*get_chars)(uint32_t termno, u8 *buf, size_t count);
76	ssize_t (*put_chars)(uint32_t termno, const u8 *buf, size_t count);
77	uint32_t	termno;
78};
79
80/* hvsi lib functions */
81struct hvc_struct;
82extern void hvsilib_init(struct hvsi_priv *pv,
83			 ssize_t (*get_chars)(uint32_t termno, u8 *buf,
84					      size_t count),
85			 ssize_t (*put_chars)(uint32_t termno, const u8 *buf,
86					      size_t count),
87			 int termno, int is_console);
88extern int hvsilib_open(struct hvsi_priv *pv, struct hvc_struct *hp);
89extern void hvsilib_close(struct hvsi_priv *pv, struct hvc_struct *hp);
90extern int hvsilib_read_mctrl(struct hvsi_priv *pv);
91extern int hvsilib_write_mctrl(struct hvsi_priv *pv, int dtr);
92extern void hvsilib_establish(struct hvsi_priv *pv);
93extern ssize_t hvsilib_get_chars(struct hvsi_priv *pv, u8 *buf, size_t count);
94extern ssize_t hvsilib_put_chars(struct hvsi_priv *pv, const u8 *buf,
95				 size_t count);
96
97#endif /* _HVSI_H */
98