treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
[muen/linux.git] / arch / mips / loongson64 / lemote-2f / ec_kb3310b.c
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);