1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Basic KB3310B Embedded Controller support for the YeeLoong 2F netbook
4 *
5 *  Copyright (C) 2008 Lemote Inc.
6 *  Author: liujl <liujl@lemote.com>, 2008-04-20
7 */
8
9#include <linux/io.h>
10#include <linux/export.h>
11#include <linux/spinlock.h>
12#include <linux/delay.h>
13
14#include "ec_kb3310b.h"
15
16static DEFINE_SPINLOCK(index_access_lock);
17static DEFINE_SPINLOCK(port_access_lock);
18
19unsigned char ec_read(unsigned short addr)
20{
21	unsigned char value;
22	unsigned long flags;
23
24	spin_lock_irqsave(&index_access_lock, flags);
25	outb((addr & 0xff00) >> 8, EC_IO_PORT_HIGH);
26	outb((addr & 0x00ff), EC_IO_PORT_LOW);
27	value = inb(EC_IO_PORT_DATA);
28	spin_unlock_irqrestore(&index_access_lock, flags);
29
30	return value;
31}
32EXPORT_SYMBOL_GPL(ec_read);
33
34void ec_write(unsigned short addr, unsigned char val)
35{
36	unsigned long flags;
37
38	spin_lock_irqsave(&index_access_lock, flags);
39	outb((addr & 0xff00) >> 8, EC_IO_PORT_HIGH);
40	outb((addr & 0x00ff), EC_IO_PORT_LOW);
41	outb(val, EC_IO_PORT_DATA);
42	/*  flush the write action */
43	inb(EC_IO_PORT_DATA);
44	spin_unlock_irqrestore(&index_access_lock, flags);
45}
46EXPORT_SYMBOL_GPL(ec_write);
47
48/*
49 * This function is used for EC command writes and corresponding status queries.
50 */
51int ec_query_seq(unsigned char cmd)
52{
53	int timeout;
54	unsigned char status;
55	unsigned long flags;
56	int ret = 0;
57
58	spin_lock_irqsave(&port_access_lock, flags);
59
60	/* make chip goto reset mode */
61	udelay(EC_REG_DELAY);
62	outb(cmd, EC_CMD_PORT);
63	udelay(EC_REG_DELAY);
64
65	/* check if the command is received by ec */
66	timeout = EC_CMD_TIMEOUT;
67	status = inb(EC_STS_PORT);
68	while (timeout-- && (status & (1 << 1))) {
69		status = inb(EC_STS_PORT);
70		udelay(EC_REG_DELAY);
71	}
72
73	spin_unlock_irqrestore(&port_access_lock, flags);
74
75	if (timeout <= 0) {
76		printk(KERN_ERR "%s: deadable error : timeout...\n", __func__);
77		ret = -EINVAL;
78	} else
79		printk(KERN_INFO
80			   "(%x/%d)ec issued command %d status : 0x%x\n",
81			   timeout, EC_CMD_TIMEOUT - timeout, cmd, status);
82
83	return ret;
84}
85EXPORT_SYMBOL_GPL(ec_query_seq);
86
87/*
88 * Send query command to EC to get the proper event number
89 */
90int ec_query_event_num(void)
91{
92	return ec_query_seq(CMD_GET_EVENT_NUM);
93}
94EXPORT_SYMBOL(ec_query_event_num);
95
96/*
97 * Get event number from EC
98 *
99 * NOTE: This routine must follow the query_event_num function in the
100 * interrupt.
101 */
102int ec_get_event_num(void)
103{
104	int timeout = 100;
105	unsigned char value;
106	unsigned char status;
107
108	udelay(EC_REG_DELAY);
109	status = inb(EC_STS_PORT);
110	udelay(EC_REG_DELAY);
111	while (timeout-- && !(status & (1 << 0))) {
112		status = inb(EC_STS_PORT);
113		udelay(EC_REG_DELAY);
114	}
115	if (timeout <= 0) {
116		pr_info("%s: get event number timeout.\n", __func__);
117
118		return -EINVAL;
119	}
120	value = inb(EC_DAT_PORT);
121	udelay(EC_REG_DELAY);
122
123	return value;
124}
125EXPORT_SYMBOL(ec_get_event_num);
126