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
 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);