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
16 static DEFINE_SPINLOCK(index_access_lock);
17 static DEFINE_SPINLOCK(port_access_lock);
18
19 unsigned 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 }
32 EXPORT_SYMBOL_GPL(ec_read);
33
34 void 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 }
46 EXPORT_SYMBOL_GPL(ec_write);
47
48 /*
49 * This function is used for EC command writes and corresponding status queries.
50 */
51 int 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 }
85 EXPORT_SYMBOL_GPL(ec_query_seq);
86
87 /*
88 * Send query command to EC to get the proper event number
89 */
90 int ec_query_event_num(void)
91 {
92 return ec_query_seq(CMD_GET_EVENT_NUM);
93 }
94 EXPORT_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 */
102 int 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 }
125 EXPORT_SYMBOL(ec_get_event_num);
126
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