drivers/input/misc/hp_sdc_rtc.c

   1 /*
   2  * HP i8042 SDC + MSM-58321 BBRTC driver.
   3  *
   4  * Copyright (c) 2001 Brian S. Julin
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions, and the following disclaimer,
  12  *    without modification.
  13  * 2. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * Alternatively, this software may be distributed under the terms of the
  17  * GNU General Public License ("GPL").
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  *
  29  * References:
  30  * System Device Controller Microprocessor Firmware Theory of Operation
  31  *      for Part Number 1820-4784 Revision B.  Dwg No. A-1820-4784-2
  32  * efirtc.c by Stephane Eranian/Hewlett Packard
  33  *
  34  */
  35
  36 #include <linux/hp_sdc.h>
  37 #include <linux/errno.h>
  38 #include <linux/types.h>
  39 #include <linux/init.h>
  40 #include <linux/module.h>
  41 #include <linux/time.h>
  42 #include <linux/miscdevice.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/poll.h>
  46 #include <linux/rtc.h>
  47 #include <linux/mutex.h>
  48 #include <linux/semaphore.h>
  49
  50 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
  51 MODULE_DESCRIPTION("HP i8042 SDC + MSM-58321 RTC Driver");
  52 MODULE_LICENSE("Dual BSD/GPL");
  53
  54 #define RTC_VERSION "1.10d"
  55
  56 static unsigned long epoch = 2000;
  57
  58 static struct semaphore i8042tregs;
  59
  60 static void hp_sdc_rtc_isr (int irq, void *dev_id,
  61                             uint8_t status, uint8_t data)
  62 {
  63         return;
  64 }
  65
  66 static int hp_sdc_rtc_do_read_bbrtc (struct rtc_time *rtctm)
  67 {
  68         struct semaphore tsem;
  69         hp_sdc_transaction t;
  70         uint8_t tseq[91];
  71         int i;
  72
  73         i = 0;
  74         while (i < 91) {
  75                 tseq[i++] = HP_SDC_ACT_DATAREG |
  76                         HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN;
  77                 tseq[i++] = 0x01;                       /* write i8042[0x70] */
  78                 tseq[i]   = i / 7;                      /* BBRTC reg address */
  79                 i++;
  80                 tseq[i++] = HP_SDC_CMD_DO_RTCR;         /* Trigger command   */
  81                 tseq[i++] = 2;          /* expect 1 stat/dat pair back.   */
  82                 i++; i++;               /* buffer for stat/dat pair       */
  83         }
  84         tseq[84] |= HP_SDC_ACT_SEMAPHORE;
  85         t.endidx =              91;
  86         t.seq =                 tseq;
  87         t.act.semaphore =       &tsem;
  88         sema_init(&tsem, 0);
  89
  90         if (hp_sdc_enqueue_transaction(&t)) return -1;
  91
  92         /* Put ourselves to sleep for results. */
  93         if (WARN_ON(down_interruptible(&tsem)))
  94                 return -1;
  95
  96         /* Check for nonpresence of BBRTC */
  97         if (!((tseq[83] | tseq[90] | tseq[69] | tseq[76] |
  98                tseq[55] | tseq[62] | tseq[34] | tseq[41] |
  99                tseq[20] | tseq[27] | tseq[6]  | tseq[13]) & 0x0f))
 100                 return -1;
 101
 102         memset(rtctm, 0, sizeof(struct rtc_time));
 103         rtctm->tm_year = (tseq[83] & 0x0f) + (tseq[90] & 0x0f) * 10;
 104         rtctm->tm_mon  = (tseq[69] & 0x0f) + (tseq[76] & 0x0f) * 10;
 105         rtctm->tm_mday = (tseq[55] & 0x0f) + (tseq[62] & 0x0f) * 10;
 106         rtctm->tm_wday = (tseq[48] & 0x0f);
 107         rtctm->tm_hour = (tseq[34] & 0x0f) + (tseq[41] & 0x0f) * 10;
 108         rtctm->tm_min  = (tseq[20] & 0x0f) + (tseq[27] & 0x0f) * 10;
 109         rtctm->tm_sec  = (tseq[6]  & 0x0f) + (tseq[13] & 0x0f) * 10;
 110
 111         return 0;
 112 }
 113
 114 static int hp_sdc_rtc_read_bbrtc (struct rtc_time *rtctm)
 115 {
 116         struct rtc_time tm, tm_last;
 117         int i = 0;
 118
 119         /* MSM-58321 has no read latch, so must read twice and compare. */
 120
 121         if (hp_sdc_rtc_do_read_bbrtc(&tm_last)) return -1;
 122         if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
 123
 124         while (memcmp(&tm, &tm_last, sizeof(struct rtc_time))) {
 125                 if (i++ > 4) return -1;
 126                 memcpy(&tm_last, &tm, sizeof(struct rtc_time));
 127                 if (hp_sdc_rtc_do_read_bbrtc(&tm)) return -1;
 128         }
 129
 130         memcpy(rtctm, &tm, sizeof(struct rtc_time));
 131
 132         return 0;
 133 }
 134
 135
 136 static int64_t hp_sdc_rtc_read_i8042timer (uint8_t loadcmd, int numreg)
 137 {
 138         hp_sdc_transaction t;
 139         uint8_t tseq[26] = {
 140                 HP_SDC_ACT_PRECMD | HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
 141                 0,
 142                 HP_SDC_CMD_READ_T1, 2, 0, 0,
 143                 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
 144                 HP_SDC_CMD_READ_T2, 2, 0, 0,
 145                 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
 146                 HP_SDC_CMD_READ_T3, 2, 0, 0,
 147                 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
 148                 HP_SDC_CMD_READ_T4, 2, 0, 0,
 149                 HP_SDC_ACT_POSTCMD | HP_SDC_ACT_DATAIN,
 150                 HP_SDC_CMD_READ_T5, 2, 0, 0
 151         };
 152
 153         t.endidx = numreg * 5;
 154
 155         tseq[1] = loadcmd;
 156         tseq[t.endidx - 4] |= HP_SDC_ACT_SEMAPHORE; /* numreg assumed > 1 */
 157
 158         t.seq =                 tseq;
 159         t.act.semaphore =       &i8042tregs;
 160
 161         /* Sleep if output regs in use. */
 162         if (WARN_ON(down_interruptible(&i8042tregs)))
 163                 return -1;
 164
 165         if (hp_sdc_enqueue_transaction(&t)) {
 166                 up(&i8042tregs);
 167                 return -1;
 168         }
 169
 170         /* Sleep until results come back. */
 171         if (WARN_ON(down_interruptible(&i8042tregs)))
 172                 return -1;
 173
 174         up(&i8042tregs);
 175
 176         return (tseq[5] |
 177                 ((uint64_t)(tseq[10]) << 8)  | ((uint64_t)(tseq[15]) << 16) |
 178                 ((uint64_t)(tseq[20]) << 24) | ((uint64_t)(tseq[25]) << 32));
 179 }
 180
 181
 182 /* Read the i8042 real-time clock */
 183 static inline int hp_sdc_rtc_read_rt(struct timespec64 *res) {
 184         int64_t raw;
 185         uint32_t tenms;
 186         unsigned int days;
 187
 188         raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_RT, 5);
 189         if (raw < 0) return -1;
 190
 191         tenms = (uint32_t)raw & 0xffffff;
 192         days  = (unsigned int)(raw >> 24) & 0xffff;
 193
 194         res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
 195         res->tv_sec =  (tenms / 100) + (time64_t)days * 86400;
 196
 197         return 0;
 198 }
 199
 200
 201 /* Read the i8042 fast handshake timer */
 202 static inline int hp_sdc_rtc_read_fhs(struct timespec64 *res) {
 203         int64_t raw;
 204         unsigned int tenms;
 205
 206         raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_FHS, 2);
 207         if (raw < 0) return -1;
 208
 209         tenms = (unsigned int)raw & 0xffff;
 210
 211         res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
 212         res->tv_sec  = (time64_t)(tenms / 100);
 213
 214         return 0;
 215 }
 216
 217
 218 /* Read the i8042 match timer (a.k.a. alarm) */
 219 static inline int hp_sdc_rtc_read_mt(struct timespec64 *res) {
 220         int64_t raw;
 221         uint32_t tenms;
 222
 223         raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_MT, 3);
 224         if (raw < 0) return -1;
 225
 226         tenms = (uint32_t)raw & 0xffffff;
 227
 228         res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
 229         res->tv_sec  = (time64_t)(tenms / 100);
 230
 231         return 0;
 232 }
 233
 234
 235 /* Read the i8042 delay timer */
 236 static inline int hp_sdc_rtc_read_dt(struct timespec64 *res) {
 237         int64_t raw;
 238         uint32_t tenms;
 239
 240         raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_DT, 3);
 241         if (raw < 0) return -1;
 242
 243         tenms = (uint32_t)raw & 0xffffff;
 244
 245         res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
 246         res->tv_sec  = (time64_t)(tenms / 100);
 247
 248         return 0;
 249 }
 250
 251
 252 /* Read the i8042 cycle timer (a.k.a. periodic) */
 253 static inline int hp_sdc_rtc_read_ct(struct timespec64 *res) {
 254         int64_t raw;
 255         uint32_t tenms;
 256
 257         raw = hp_sdc_rtc_read_i8042timer(HP_SDC_CMD_LOAD_CT, 3);
 258         if (raw < 0) return -1;
 259
 260         tenms = (uint32_t)raw & 0xffffff;
 261
 262         res->tv_nsec = (long)(tenms % 100) * 10000 * 1000;
 263         res->tv_sec  = (time64_t)(tenms / 100);
 264
 265         return 0;
 266 }
 267
 268 static int hp_sdc_rtc_proc_show(struct seq_file *m, void *v)
 269 {
 270 #define YN(bit) ("no")
 271 #define NY(bit) ("yes")
 272         struct rtc_time tm;
 273         struct timespec64 tv;
 274
 275         memset(&tm, 0, sizeof(struct rtc_time));
 276
 277         if (hp_sdc_rtc_read_bbrtc(&tm)) {
 278                 seq_puts(m, "BBRTC\t\t: READ FAILED!\n");
 279         } else {
 280                 seq_printf(m,
 281                              "rtc_time\t: %ptRt\n"
 282                              "rtc_date\t: %ptRd\n"
 283                              "rtc_epoch\t: %04lu\n",
 284                              &tm, &tm, epoch);
 285         }
 286
 287         if (hp_sdc_rtc_read_rt(&tv)) {
 288                 seq_puts(m, "i8042 rtc\t: READ FAILED!\n");
 289         } else {
 290                 seq_printf(m, "i8042 rtc\t: %lld.%02ld seconds\n",
 291                              (s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
 292         }
 293
 294         if (hp_sdc_rtc_read_fhs(&tv)) {
 295                 seq_puts(m, "handshake\t: READ FAILED!\n");
 296         } else {
 297                 seq_printf(m, "handshake\t: %lld.%02ld seconds\n",
 298                              (s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
 299         }
 300
 301         if (hp_sdc_rtc_read_mt(&tv)) {
 302                 seq_puts(m, "alarm\t\t: READ FAILED!\n");
 303         } else {
 304                 seq_printf(m, "alarm\t\t: %lld.%02ld seconds\n",
 305                              (s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
 306         }
 307
 308         if (hp_sdc_rtc_read_dt(&tv)) {
 309                 seq_puts(m, "delay\t\t: READ FAILED!\n");
 310         } else {
 311                 seq_printf(m, "delay\t\t: %lld.%02ld seconds\n",
 312                              (s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
 313         }
 314
 315         if (hp_sdc_rtc_read_ct(&tv)) {
 316                 seq_puts(m, "periodic\t: READ FAILED!\n");
 317         } else {
 318                 seq_printf(m, "periodic\t: %lld.%02ld seconds\n",
 319                              (s64)tv.tv_sec, (long)tv.tv_nsec/1000000L);
 320         }
 321
 322         seq_printf(m,
 323                      "DST_enable\t: %s\n"
 324                      "BCD\t\t: %s\n"
 325                      "24hr\t\t: %s\n"
 326                      "square_wave\t: %s\n"
 327                      "alarm_IRQ\t: %s\n"
 328                      "update_IRQ\t: %s\n"
 329                      "periodic_IRQ\t: %s\n"
 330                      "periodic_freq\t: %ld\n"
 331                      "batt_status\t: %s\n",
 332                      YN(RTC_DST_EN),
 333                      NY(RTC_DM_BINARY),
 334                      YN(RTC_24H),
 335                      YN(RTC_SQWE),
 336                      YN(RTC_AIE),
 337                      YN(RTC_UIE),
 338                      YN(RTC_PIE),
 339                      1UL,
 340                      1 ? "okay" : "dead");
 341
 342         return 0;
 343 #undef YN
 344 #undef NY
 345 }
 346
 347 static int __init hp_sdc_rtc_init(void)
 348 {
 349         int ret;
 350
 351 #ifdef __mc68000__
 352         if (!MACH_IS_HP300)
 353                 return -ENODEV;
 354 #endif
 355
 356         sema_init(&i8042tregs, 1);
 357
 358         if ((ret = hp_sdc_request_timer_irq(&hp_sdc_rtc_isr)))
 359                 return ret;
 360
 361         proc_create_single("driver/rtc", 0, NULL, hp_sdc_rtc_proc_show);
 362
 363         printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support loaded "
 364                          "(RTC v " RTC_VERSION ")\n");
 365
 366         return 0;
 367 }
 368
 369 static void __exit hp_sdc_rtc_exit(void)
 370 {
 371         remove_proc_entry ("driver/rtc", NULL);
 372         hp_sdc_release_timer_irq(hp_sdc_rtc_isr);
 373         printk(KERN_INFO "HP i8042 SDC + MSM-58321 RTC support unloaded\n");
 374 }
 375
 376 module_init(hp_sdc_rtc_init);
 377 module_exit(hp_sdc_rtc_exit);