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diff --git a/board/gen860t/beeper.c b/board/gen860t/beeper.c
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+/*
+ * (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: */
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