LXR uboot/board/gen860t/beeper.c

   1/*
   2 * (C) Copyright 2002
   3 * Keith Outwater, keith_outwater@mvis.com
   4 *
   5 * See file CREDITS for list of people who contributed to this
   6 * project.
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License as
  10 * published by the Free Software Foundation; either version 2 of
  11 * the License, or (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21 * MA 02111-1307 USA
  22 */
  23
  24#include <common.h>
  25#include <mpc8xx.h>
  26#include <asm/8xx_immap.h>
  27#include <linux/ctype.h>
  28
  29/*
  30 * Basic beeper support for the GEN860T board.  The GEN860T includes
  31 * an audio sounder driven by a Phillips TDA8551 amplifier.  The
  32 * TDA8551 features a digital volume control which uses a "trinary"
  33 * input (high/high-Z/low) to set volume.  The 860's SPKROUT pin
  34 * drives the amplifier input.
  35 */
  36
  37/*
  38 * Initialize beeper-related hardware. Initialize timer 1 for use with
  39 * the beeper. Use 66 MHz internal clock with prescale of 33 to get
  40 * 1 uS period per count.
  41 * FIXME: we should really compute the prescale based on the reported
  42 * core clock frequency.
  43 */
  44void init_beeper (void)
  45{
  46        volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
  47
  48        immap->im_cpmtimer.cpmt_tgcr &= ~TGCR_RST1 | TGCR_STP1;
  49        immap->im_cpmtimer.cpmt_tmr1 = ((33 << TMR_PS_SHIFT) & TMR_PS_MSK)
  50                | TMR_OM | TMR_FRR | TMR_ICLK_IN_GEN;
  51        immap->im_cpmtimer.cpmt_tcn1 = 0;
  52        immap->im_cpmtimer.cpmt_ter1 = 0xffff;
  53        immap->im_cpmtimer.cpmt_tgcr |= TGCR_RST1;
  54}
  55
  56/*
  57 * Set beeper frequency.  Max allowed frequency is 2.5 KHz.  This limit
  58 * is mostly arbitrary, but the beeper isn't really much good beyond this
  59 * frequency.
  60 */
  61void set_beeper_frequency (uint frequency)
  62{
  63#define FREQ_LIMIT      2500
  64
  65        volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
  66
  67        /*
  68         * Compute timer ticks given desired frequency.  The timer is set up
  69         * to count 0.5 uS per tick and it takes two ticks per cycle (Hz).
  70         */
  71        if (frequency > FREQ_LIMIT)
  72                frequency = FREQ_LIMIT;
  73        frequency = 1000000 / frequency;
  74        immap->im_cpmtimer.cpmt_trr1 = (ushort) frequency;
  75}
  76
  77/*
  78 * Turn the beeper on
  79 */
  80void beeper_on (void)
  81{
  82        volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
  83
  84        immap->im_cpmtimer.cpmt_tgcr &= ~TGCR_STP1;
  85}
  86
  87/*
  88 * Turn the beeper off
  89 */
  90void beeper_off (void)
  91{
  92        volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
  93
  94        immap->im_cpmtimer.cpmt_tgcr |= TGCR_STP1;
  95}
  96
  97/*
  98 * Increase or decrease the beeper volume.  Volume can be set
  99 * from off to full in 64 steps.  To increase volume, the output
 100 * pin is actively driven high, then returned to tristate.
 101 * To decrease volume, output a low on the port pin (no need to
 102 * change pin mode to tristate) then output a high to go back to
 103 * tristate.
 104 */
 105void set_beeper_volume (int steps)
 106{
 107        volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 108        int i;
 109
 110        if (steps >= 0) {
 111                for (i = 0; i < (steps >= 64 ? 64 : steps); i++) {
 112                        immap->im_cpm.cp_pbodr &= ~(0x80000000 >> 19);
 113                        udelay (1);
 114                        immap->im_cpm.cp_pbodr |= (0x80000000 >> 19);
 115                        udelay (1);
 116                }
 117        } else {
 118                for (i = 0; i > (steps <= -64 ? -64 : steps); i--) {
 119                        immap->im_cpm.cp_pbdat &= ~(0x80000000 >> 19);
 120                        udelay (1);
 121                        immap->im_cpm.cp_pbdat |= (0x80000000 >> 19);
 122                        udelay (1);
 123                }
 124        }
 125}
 126
 127/*
 128 * Check the environment to see if the beeper needs beeping.
 129 * Controlled by a sequence of the form:
 130 * freq/delta volume/on time/off time;... where:
 131 * freq                 = frequency in Hz (0 - 2500)
 132 * delta volume = volume steps up or down (-64 <= vol <= 64)
 133 * on time              = time in mS
 134 * off time             = time in mS
 135 *
 136 * Return 1 on success, 0 on failure
 137 */
 138int do_beeper (char *sequence)
 139{
 140#define DELIMITER       ';'
 141
 142        int args[4];
 143        int i;
 144        int val;
 145        char *p = sequence;
 146        char *tp;
 147
 148        /*
 149         * Parse the control sequence.  This is a really simple parser
 150         * without any real error checking.  You can probably blow it
 151         * up really easily.
 152         */
 153        if (*p == '\0' || !isdigit (*p)) {
 154                printf ("%s:%d: null or invalid string (%s)\n",
 155                        __FILE__, __LINE__, p);
 156                return 0;
 157        }
 158
 159        i = 0;
 160        while (*p != '\0') {
 161                while (*p != DELIMITER) {
 162                        if (i > 3)
 163                                i = 0;
 164                        val = (int) simple_strtol (p, &tp, 0);
 165                        if (tp == p) {
 166                                printf ("%s:%d: no digits or bad format\n",
 167                                        __FILE__, __LINE__);
 168                                return 0;
 169                        } else {
 170                                args[i] = val;
 171                        }
 172
 173                        i++;
 174                        if (*tp == DELIMITER)
 175                                p = tp;
 176                        else
 177                                p = ++tp;
 178                }
 179                p++;
 180
 181                /*
 182                 * Well, we got something that has a chance of being correct
 183                 */
 184#if 0
 185                for (i = 0; i < 4; i++) {
 186                        printf ("%s:%d:arg %d = %d\n", __FILE__, __LINE__, i,
 187                                args[i]);
 188                }
 189                printf ("\n");
 190#endif
 191                set_beeper_frequency (args[0]);
 192                set_beeper_volume (args[1]);
 193                beeper_on ();
 194                udelay (1000 * args[2]);
 195                beeper_off ();
 196                udelay (1000 * args[3]);
 197        }
 198        return 1;
 199}
 200