r4542 - in developers/werner: . mmcds

[werner at docs.openmoko.org]

Author: werner
Date: 2008-07-20 04:12:32 +0200 (Sun, 20 Jul 2008)
New Revision: 4542

Added:
   developers/werner/mmcds/
   developers/werner/mmcds/Makefile
   developers/werner/mmcds/mmcds.c
Log:
MMC Drive Strength get/set utility. (GTA02)



Added: developers/werner/mmcds/Makefile
===================================================================
--- developers/werner/mmcds/Makefile	                        (rev 0)
+++ developers/werner/mmcds/Makefile	2008-07-20 02:12:32 UTC (rev 4542)
@@ -0,0 +1,5 @@
+CC=arm-angstrom-linux-gnueabi-gcc
+
+CFLAGS=-Wall -g
+
+all:		mmcds

Added: developers/werner/mmcds/mmcds.c
===================================================================
--- developers/werner/mmcds/mmcds.c	                        (rev 0)
+++ developers/werner/mmcds/mmcds.c	2008-07-20 02:12:32 UTC (rev 4542)
@@ -0,0 +1,94 @@
+/*
+ * mmcds.c - Get/set the MMC drive strength (of the Smedia Glamo 3362)
+ *
+ * Copyright (C) 2008 by OpenMoko, Inc.
+ * Written by Werner Almesberger <werner at openmoko.org>
+ * All Rights Reserved
+ *  
+ * 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.
+ */
+
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+
+#define BASE 0x08000000
+
+#define MMC_BASIC (*(uint16_t *) (mem+0x1430))
+
+static volatile void *mem;
+
+
+/* ----- Register decoding ------------------------------------------------- */
+
+
+static const char *strength[] = { "min", "low", "high", "max" };
+
+static void show_mmc_basic(uint16_t reg)
+{
+	int drv = (reg >> 6) & 3;
+
+	printf("MMC_BASIC = 0x%04x\n", reg);
+	printf("  MCGIODrv = %d (%s)\n", drv, strength[drv]);
+}
+
+
+/* ----- Command-line parsing ---------------------------------------------- */
+
+
+static void __attribute__((noreturn)) usage(const char *name)
+{
+	fprintf(stderr, "usage: %s [min|low|high|max|0|1|2|3]\n", name);
+	exit(1);
+}
+
+
+static int decode(const char *name, const char *arg)
+{
+	int i;
+
+	for (i = 0; i != 4; i++)
+		if (!strcmp(strength[i], arg) ||
+		    (arg[0] == '0'+i && !arg[1]))
+			return i;
+	usage(name);
+}
+
+
+int main(int argc, char **argv)
+{
+	int fd, new;
+
+	fd = open("/dev/mem", O_RDWR);
+        if (fd < 0) {
+		perror("/dev/mem");
+		exit(1);
+	}
+	mem = mmap(NULL, 0x2000, PROT_READ | PROT_WRITE, MAP_SHARED, fd, BASE);
+	if (mem == MAP_FAILED) {
+		perror("mmap");
+		exit(1);
+	}
+	switch (argc) {
+	case 1:
+		show_mmc_basic(MMC_BASIC);
+		break;
+	case 2:
+		new = decode(*argv, argv[1]);
+		/* should disable interrupts around here */
+		MMC_BASIC = (MMC_BASIC & ~(uint16_t) 0xc0) | (new << 6);
+		/* should disable interrupts around here */
+		break;
+	default:
+		usage(*argv);
+	}
+	return 0;
+}