arch/mips/loongson/lemote-2f/ec_kb3310b.c

   1 /*
   2  * Basic KB3310B Embedded Controller support for the YeeLoong 2F netbook
   3  *
   4  *  Copyright (C) 2008 Lemote Inc.
   5  *  Author: liujl <liujl@lemote.com>, 2008-04-20
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/delay.h>
  16
  17 #include "ec_kb3310b.h"
  18
  19 static DEFINE_SPINLOCK(index_access_lock);
  20 static DEFINE_SPINLOCK(port_access_lock);
  21
  22 unsigned char ec_read(unsigned short addr)
  23 {
  24         unsigned char value;
  25         unsigned long flags;
  26
  27         spin_lock_irqsave(&index_access_lock, flags);
  28         outb((addr & 0xff00) >> 8, EC_IO_PORT_HIGH);
  29         outb((addr & 0x00ff), EC_IO_PORT_LOW);
  30         value = inb(EC_IO_PORT_DATA);
  31         spin_unlock_irqrestore(&index_access_lock, flags);
  32
  33         return value;
  34 }
  35 EXPORT_SYMBOL_GPL(ec_read);
  36
  37 void ec_write(unsigned short addr, unsigned char val)
  38 {
  39         unsigned long flags;
  40
  41         spin_lock_irqsave(&index_access_lock, flags);
  42         outb((addr & 0xff00) >> 8, EC_IO_PORT_HIGH);
  43         outb((addr & 0x00ff), EC_IO_PORT_LOW);
  44         outb(val, EC_IO_PORT_DATA);
  45         /*  flush the write action */
  46         inb(EC_IO_PORT_DATA);
  47         spin_unlock_irqrestore(&index_access_lock, flags);
  48 }
  49 EXPORT_SYMBOL_GPL(ec_write);
  50
  51 /*
  52  * This function is used for EC command writes and corresponding status queries.
  53  */
  54 int ec_query_seq(unsigned char cmd)
  55 {
  56         int timeout;
  57         unsigned char status;
  58         unsigned long flags;
  59         int ret = 0;
  60
  61         spin_lock_irqsave(&port_access_lock, flags);
  62
  63         /* make chip goto reset mode */
  64         udelay(EC_REG_DELAY);
  65         outb(cmd, EC_CMD_PORT);
  66         udelay(EC_REG_DELAY);
  67
  68         /* check if the command is received by ec */
  69         timeout = EC_CMD_TIMEOUT;
  70         status = inb(EC_STS_PORT);
  71         while (timeout-- && (status & (1 << 1))) {
  72                 status = inb(EC_STS_PORT);
  73                 udelay(EC_REG_DELAY);
  74         }
  75
  76         spin_unlock_irqrestore(&port_access_lock, flags);
  77
  78         if (timeout <= 0) {
  79                 printk(KERN_ERR "%s: deadable error : timeout...\n", __func__);
  80                 ret = -EINVAL;
  81         } else
  82                 printk(KERN_INFO
  83                            "(%x/%d)ec issued command %d status : 0x%x\n",
  84                            timeout, EC_CMD_TIMEOUT - timeout, cmd, status);
  85
  86         return ret;
  87 }
  88 EXPORT_SYMBOL_GPL(ec_query_seq);
  89
  90 /*
  91  * Send query command to EC to get the proper event number
  92  */
  93 int ec_query_event_num(void)
  94 {
  95         return ec_query_seq(CMD_GET_EVENT_NUM);
  96 }
  97 EXPORT_SYMBOL(ec_query_event_num);
  98
  99 /*
 100  * Get event number from EC
 101  *
 102  * NOTE: This routine must follow the query_event_num function in the
 103  * interrupt.
 104  */
 105 int ec_get_event_num(void)
 106 {
 107         int timeout = 100;
 108         unsigned char value;
 109         unsigned char status;
 110
 111         udelay(EC_REG_DELAY);
 112         status = inb(EC_STS_PORT);
 113         udelay(EC_REG_DELAY);
 114         while (timeout-- && !(status & (1 << 0))) {
 115                 status = inb(EC_STS_PORT);
 116                 udelay(EC_REG_DELAY);
 117         }
 118         if (timeout <= 0) {
 119                 pr_info("%s: get event number timeout.\n", __func__);
 120
 121                 return -EINVAL;
 122         }
 123         value = inb(EC_DAT_PORT);
 124         udelay(EC_REG_DELAY);
 125
 126         return value;
 127 }
 128 EXPORT_SYMBOL(ec_get_event_num);