/* * (C) Copyright 2002 * Keith Outwater, keith_outwater@mvis.com * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <common.h> #include <mpc8xx.h> #include <asm/8xx_immap.h> #include <linux/ctype.h> /* * Basic beeper support for the GEN860T board. The GEN860T includes * an audio sounder driven by a Phillips TDA8551 amplifier. The * TDA8551 features a digital volume control which uses a "trinary" * input (high/high-Z/low) to set volume. The 860's SPKROUT pin * drives the amplifier input. */ /* * Initialize beeper-related hardware. Initialize timer 1 for use with * the beeper. Use 66 Mhz internal clock with prescale of 33 to get * 1 uS period per count. * FIXME: we should really compute the prescale based on the reported * core clock frequency. */ void init_beeper(void) { volatile immap_t *immap = (immap_t *)CFG_IMMR; immap->im_cpmtimer.cpmt_tgcr &= ~TGCR_RST1 | TGCR_STP1; immap->im_cpmtimer.cpmt_tmr1 = ((33 << TMR_PS_SHIFT) & TMR_PS_MSK) | TMR_OM | TMR_FRR | TMR_ICLK_IN_GEN; immap->im_cpmtimer.cpmt_tcn1 = 0; immap->im_cpmtimer.cpmt_ter1 = 0xffff; immap->im_cpmtimer.cpmt_tgcr |= TGCR_RST1; } /* * Set beeper frequency. Max allowed frequency is 2.5 KHz. This limit * is mostly arbitrary, but the beeper isn't really much good beyond this * frequency. */ void set_beeper_frequency(uint frequency) { #define FREQ_LIMIT 2500 volatile immap_t *immap = (immap_t *)CFG_IMMR; /* * Compute timer ticks given desired frequency. The timer is set up * to count 0.5 uS per tick and it takes two ticks per cycle (Hz). */ if (frequency > FREQ_LIMIT) frequency = FREQ_LIMIT; frequency = 1000000/frequency; immap->im_cpmtimer.cpmt_trr1 = (ushort)frequency; } /* * Turn the beeper on */ void beeper_on(void) { volatile immap_t *immap = (immap_t *)CFG_IMMR; immap->im_cpmtimer.cpmt_tgcr &= ~TGCR_STP1; } /* * Turn the beeper off */ void beeper_off(void) { volatile immap_t *immap = (immap_t *)CFG_IMMR; immap->im_cpmtimer.cpmt_tgcr |= TGCR_STP1; } /* * Increase or decrease the beeper volume. Volume can be set * from off to full in 64 steps. To increase volume, the output * pin is actively driven high, then returned to tristate. * To decrease volume, output a low on the port pin (no need to * change pin mode to tristate) then output a high to go back to * tristate. */ void set_beeper_volume(int steps) { volatile immap_t *immap = (immap_t *)CFG_IMMR; int i; if (steps >= 0) { for (i = 0; i < (steps >= 64 ? 64 : steps); i++) { immap->im_cpm.cp_pbodr &= ~(0x80000000 >> 19); udelay(1); immap->im_cpm.cp_pbodr |= (0x80000000 >> 19); udelay(1); } } else { for (i = 0; i > (steps <= -64 ? -64 : steps); i--) { immap->im_cpm.cp_pbdat &= ~(0x80000000 >> 19); udelay(1); immap->im_cpm.cp_pbdat |= (0x80000000 >> 19); udelay(1); } } } /* * Check the environment to see if the beeper needs beeping. * Controlled by a sequence of the form: * freq/delta volume/on time/off time;... where: * freq = frequency in Hz (0 - 2500) * delta volume = volume steps up or down (-64 <= vol <= 64) * on time = time in mS * off time = time in mS * * Return 1 on success, 0 on failure */ int do_beeper(char *sequence) { #define DELIMITER ';' int args[4]; int i; int val; char *p = sequence; char *tp; /* * Parse the control sequence. This is a really simple parser * without any real error checking. You can probably blow it * up really easily. */ if (*p == '\0' || !isdigit(*p)) { printf("%s:%d: null or invalid string (%s)\n", __FILE__, __LINE__, p); return 0; } i = 0; while (*p != '\0') { while (*p != DELIMITER) { if (i > 3) i = 0; val = (int) simple_strtol(p, &tp, 0); if (tp == p) { printf("%s:%d: no digits or bad format\n", __FILE__,__LINE__); return 0; } else { args[i] = val; } i++; if (*tp == DELIMITER) p = tp; else p = ++tp; } p++; /* * Well, we got something that has a chance of being correct */ #if 0 for (i = 0; i < 4; i++) { printf("%s:%d:arg %d = %d\n", __FILE__, __LINE__, i, args[i]); } printf("\n"); #endif set_beeper_frequency(args[0]); set_beeper_volume(args[1]); beeper_on(); udelay(1000 * args[2]); beeper_off(); udelay(1000 * args[3]); } return 1; } /* vim: set ts=4 sw=4 tw=78: */