/*
* HP i8042 SDC + MSM-58321 BBRTC driver.
*
* Copyright (c) 2001 Brian S. Julin
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL").
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
*
* References:
* System Device Controller Microprocessor Firmware Theory of Operation
* for Part Number 1820-4784 Revision B. Dwg No. A-1820-4784-2
* efirtc.c by Stephane Eranian/Hewlett Packard
*
*/
#include <linux/hp_sdc.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/time.h>
#include <linux/miscdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/rtc.h>
#include <linux/mutex.h>
#include <linux/semaphore.h>
MODULE_AUTHOR("Brian S. Julin <[email protected]>");
MODULE_DESCRIPTION("HP i8042 SDC + MSM-58321 RTC Driver");
MODULE_LICENSE("Dual BSD/GPL");
#define RTC_VERSION "1.10d"
static unsigned long epoch = 2000;
static struct semaphore i8042tregs;
static void hp_sdc_rtc_isr (int irq, void *dev_id,
uint8_t status, uint8_t data)
{
return;
}
static int hp_sdc_rtc_do_read_bbrtc (struct rtc_time *rtctm)
{
struct semaphore tsem;
hp_sdc_transaction t;
uint8_t tseq[91];
int i;
i = 0;
while (i < 91) {
tseq[i++] = HP_SDC_ACT_DATAREG |
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN;
tseq[i++] = 0x01; /* write i8042[0x70] */
tseq[i] = i / 7; /* BBRTC reg address */
i++;
tseq[i++] = HP_SDC_CMD_DO_RTCR; /* Trigger command */
tseq[i++] = 2; /* expect 1 stat/dat pair back. */
i++; i++; /* buffer for stat/dat pair */
}
tseq[84] |= HP_SDC_ACT_SEMAPHORE;
t.endidx = 91;
t.seq = tseq;
t.act.semaphore = &tsem;
sema_init(&tsem, 0);
if (hp_sdc_enqueue_transaction(&t)) return -1;
/* Put ourselves to sleep for results. */
if (WARN_ON(down_interruptible(&tsem)))
return -1;
/* Check for nonpresence of BBRTC */
if (!((tseq[83] | tseq[90] | tseq[69] | tseq[76] |
tseq[55] | tseq[62] | tseq[34] | tseq[41] |
tseq[20] | tseq[27] | tseq[6] | tseq[13]) & 0x0f))
return -1;
memset(rtctm, 0, sizeof(struct rtc_time));
rtctm->tm_year = (tseq[83] & 0x0f) + (tseq[90] & 0x0f) * 10;
rtctm->tm_mon = (tseq[69] & 0x0f) + (tseq[76] & 0x0f) * 10;
rtctm->tm_mday = (tseq[55] & 0x0f) + (tseq[62] & 0x0f) * 10;
rtctm->tm_wday = (tseq[48] & 0x0f);
rtctm->tm_hour = (tseq[34] & 0x0f) + (tseq[41] & 0x0f) * 10;
rtctm->tm_min = (tseq[20] & 0x0f) + (tseq[27] & 0x0f) * 10;
rtctm->tm_sec = (tseq[6] & 0x0f) + (tseq[13] & 0x0f) * 10;
return 0;
}
static int hp_sdc_rtc_read_bbrtc (struct rtc_time *rtctm)
{
struct rtc_time tm, tm_last;
int i = 0;
/* MSM-58321 has no read latch, so must read twice and compare. */
if (hp_sdc_rtc_do_read_bbrtc(&tm_last)) return -1;
if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
while (memcmp(&tm, &tm_last, sizeof(struct rtc_time))) {
if (i++ > 4) return -1;
memcpy(&tm_last, &tm, sizeof(struct rtc_time));
if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
}
memcpy(rtctm, &tm, sizeof(struct rtc_time));
return 0;
}
static int64_t hp_sdc_rtc_read_i8042timer (uint8_t loadcmd, int numreg)
{
hp_sdc_transaction t;
uint8_t tseq[26] = {
HP_SDC_ACT_PRECMD | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
0,
HP_SDC_CMD_READ_T1, 2, 0, 0,
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
HP_SDC_CMD_READ_T2, 2, 0, 0,
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
HP_SDC_CMD_READ_T3, 2, 0, 0,
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
HP_SDC_CMD_READ_T4, 2, 0, 0,
HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
HP_SDC_CMD_READ_T5, 2, 0, 0
};
t.endidx = numreg * 5;
tseq[1] = loadcmd;
tseq[t.endidx - 4] |= HP_SDC_ACT_SEMAPHORE; /* numreg assumed > 1 */
t.seq = tseq;
t.act.semaphore = &i8042tregs;
/* Sleep if output regs in use. */
if (WARN_ON(down_interruptible(&i8042tregs)))
return -1;
if (hp_sdc_enqueue_transaction(&t)) {
up(&i8042tregs);
return -1;
}
/* Sleep until results come back. */
if (WARN_ON(down_interruptible(&i8042tregs)))
return -1;
up(&i8042tregs);
return (tseq[5] |
((uint64_t)(tseq[10]) << 8) | ((uint64_t)(tseq[15]) << 16) |
((uint64_t)(tseq[20]) << 24) | ((uint64_t)(tseq[25]) << 32));
}
/* Read the i8042 real-time clock */
static inline int hp_sdc_rtc_read_rt(struct timespec64 *res) {
int64_t raw;
uint32_t tenms;
unsigned int days;
raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_RT, 5);
if (raw < 0) return -1;
tenms = (uint32_t)raw & 0xffffff;
days = (unsigned int)(raw >> 24) & 0xffff;
res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
res->tv_sec = (tenms / 100) + (time64_t)days * 86400;
return 0;
}
/* Read the i8042 fast handshake timer */
static inline int hp_sdc_rtc_read_fhs(struct timespec64 *res) {
int64_t raw;
unsigned int tenms;
raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_FHS, 2);
if (raw < 0) return -1;
tenms = (unsigned int)raw & 0xffff;
res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
res->tv_sec = (time64_t)(tenms / 100);
return 0;
}
/* Read the i8042 match timer (a.k.a. alarm) */
static inline int hp_sdc_rtc_read_mt(struct timespec64 *res) {
int64_t raw;
uint32_t tenms;
raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_MT, 3);
if (raw < 0) return -1;
tenms = (uint32_t)raw & 0xffffff;
res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
res->tv_sec = (time64_t)(tenms / 100);
return 0;
}
/* Read the i8042 delay timer */
static inline int hp_sdc_rtc_read_dt(struct timespec64 *res) {
int64_t raw;
uint32_t tenms;
raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_DT, 3);
if (raw < 0) return -1;
tenms = (uint32_t)raw & 0xffffff;
res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
res->tv_sec = (time64_t)(tenms / 100);
return 0;
}
/* Read the i8042 cycle timer (a.k.a. periodic) */
static inline int hp_sdc_rtc_read_ct(struct timespec64 *res) {
int64_t raw;
uint32_t tenms;
raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_CT, 3);
if (raw < 0) return -1;
tenms = (uint32_t)raw & 0xffffff;
res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
res->tv_sec = (time64_t)(tenms / 100);
return 0;
}
static int __maybe_unused hp_sdc_rtc_proc_show(struct seq_file *m, void *v)
{
#define YN(bit) ("no")
#define NY(bit) ("yes")
struct rtc_time tm;
struct timespec64 tv;
memset(&tm, 0, sizeof(struct rtc_time));
if (hp_sdc_rtc_read_bbrtc(&tm)) {
seq_puts(m, "BBRTC\t\t: READ FAILED!\n");
} else {
seq_printf(m,
"rtc_time\t: %ptRt\n"
"rtc_date\t: %ptRd\n"
"rtc_epoch\t: %04lu\n",
&tm, &tm, epoch);
}
if (hp_sdc_rtc_read_rt(&tv)) {
seq_puts(m, "i8042 rtc\t: READ FAILED!\n");
} else {
seq_printf(m, "i8042 rtc\t: %lld.%02ld seconds\n",
(s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
}
if (hp_sdc_rtc_read_fhs(&tv)) {
seq_puts(m, "handshake\t: READ FAILED!\n");
} else {
seq_printf(m, "handshake\t: %lld.%02ld seconds\n",
(s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
}
if (hp_sdc_rtc_read_mt(&tv)) {
seq_puts(m, "alarm\t\t: READ FAILED!\n");
} else {
seq_printf(m, "alarm\t\t: %lld.%02ld seconds\n",
(s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
}
if (hp_sdc_rtc_read_dt(&tv)) {
seq_puts(m, "delay\t\t: READ FAILED!\n");
} else {
seq_printf(m, "delay\t\t: %lld.%02ld seconds\n",
(s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
}
if (hp_sdc_rtc_read_ct(&tv)) {
seq_puts(m, "periodic\t: READ FAILED!\n");
} else {
seq_printf(m, "periodic\t: %lld.%02ld seconds\n",
(s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
}
seq_printf(m,
"DST_enable\t: %s\n"
"BCD\t\t: %s\n"
"24hr\t\t: %s\n"
"square_wave\t: %s\n"
"alarm_IRQ\t: %s\n"
"update_IRQ\t: %s\n"
"periodic_IRQ\t: %s\n"
"periodic_freq\t: %ld\n"
"batt_status\t: %s\n",
YN(RTC_DST_EN),
NY(RTC_DM_BINARY),
YN(RTC_24H),
YN(RTC_SQWE),
YN(RTC_AIE),
YN(RTC_UIE),
YN(RTC_PIE),
1UL,
1 ? "okay" : "dead");
return 0;
#undef YN
#undef NY
}
static int __init hp_sdc_rtc_init(void)
{
int ret;
#ifdef __mc68000__
if (!MACH_IS_HP300)
return -ENODEV;
#endif
sema_init(&i8042tregs, 1);
if ((ret = hp_sdc_request_timer_irq(&hp_sdc_rtc_isr)))
return ret;
proc_create_single("driver/rtc", 0, NULL, hp_sdc_rtc_proc_show);
printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support loaded "
"(RTC v " RTC_VERSION ")\n");
return 0;
}
static void __exit hp_sdc_rtc_exit(void)
{
remove_proc_entry ("driver/rtc", NULL);
hp_sdc_release_timer_irq(hp_sdc_rtc_isr);
printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support unloaded\n");
}
module_init(hp_sdc_rtc_init);
module_exit(hp_sdc_rtc_exit);
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