[PATCH] I2C: Add support for multiple I2C busses for RTC & DTT

This patch switches to the desired I2C bus when the date/dtt
commands are called. This can be configured using the
CFG_RTC_BUS_NUM and/or CFG_DTT_BUS_NUM defines.

Signed-off-by: Stefan Roese <sr@denx.de>

4 files changed, 40 insertions, 9 deletions

diff --git a/README b/README
index ecfd1f82f0..15428643ed 100644
--- a/README
+++ b/README
@@ -1347,6 +1347,16 @@ The following options need to be configured:
 		If defined, then this indicates the I2C bus number for DDR SPD.
 		If not defined, then U-Boot assumes that SPD is on I2C bus 0.
 
+		CFG_RTC_BUS_NUM
+
+		If defined, then this indicates the I2C bus number for the RTC.
+		If not defined, then U-Boot assumes that RTC is on I2C bus 0.
+
+		CFG_DTT_BUS_NUM
+
+		If defined, then this indicates the I2C bus number for the DTT.
+		If not defined, then U-Boot assumes that DTT is on I2C bus 0.
+
 		CONFIG_FSL_I2C
 
 		Define this option if you want to use Freescale's I2C driver in
diff --git a/common/cmd_date.c b/common/cmd_date.c
index 84932f7568..33d2e5661e 100644
--- a/common/cmd_date.c
+++ b/common/cmd_date.c
@@ -27,6 +27,7 @@
 #include <common.h>
 #include <command.h>
 #include <rtc.h>
+#include <i2c.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -44,6 +45,11 @@ int do_date (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 {
 	struct rtc_time tm;
 	int rcode = 0;
+	int old_bus;
+
+	/* switch to correct I2C bus */
+	old_bus = I2C_GET_BUS();
+	I2C_SET_BUS(CFG_RTC_BUS_NUM);
 
 	switch (argc) {
 	case 2:			/* set date & time */
@@ -56,7 +62,7 @@ int do_date (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 			/* insert new date & time */
 			if (mk_date (argv[1], &tm) != 0) {
 				puts ("## Bad date format\n");
-				return 1;
+				break;
 			}
 			/* and write to RTC */
 			rtc_set (&tm);
@@ -71,11 +77,15 @@ int do_date (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 				"unknown " : RELOC(weekdays[tm.tm_wday]),
 			tm.tm_hour, tm.tm_min, tm.tm_sec);
 
-		return 0;
+		break;
 	default:
 		printf ("Usage:\n%s\n", cmdtp->usage);
 		rcode = 1;
 	}
+
+	/* switch back to original I2C bus */
+	I2C_SET_BUS(old_bus);
+
 	return rcode;
 }
 
diff --git a/common/cmd_dtt.c b/common/cmd_dtt.c
index 9db64e9e3d..4f7b049d79 100644
--- a/common/cmd_dtt.c
+++ b/common/cmd_dtt.c
@@ -28,19 +28,27 @@
 #if (CONFIG_COMMANDS & CFG_CMD_DTT)
 
 #include <dtt.h>
+#include <i2c.h>
 
 int do_dtt (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
 {
 	int i;
 	unsigned char sensors[] = CONFIG_DTT_SENSORS;
+	int old_bus;
+
+	/* switch to correct I2C bus */
+	old_bus = I2C_GET_BUS();
+	I2C_SET_BUS(CFG_DTT_BUS_NUM);
 
 	/*
 	 * Loop through sensors, read
 	 * temperature, and output it.
 	 */
-	for (i = 0; i < sizeof (sensors); i++) {
+	for (i = 0; i < sizeof (sensors); i++)
 		printf ("DTT%d: %i C\n", i + 1, dtt_get_temp (sensors[i]));
-	}
+
+	/* switch back to original I2C bus */
+	I2C_SET_BUS(old_bus);
 
 	return 0;
 }	/* do_dtt() */
diff --git a/dtt/adm1021.c b/dtt/adm1021.c
index 14c38f0a83..9f65cfb274 100644
--- a/dtt/adm1021.c
+++ b/dtt/adm1021.c
@@ -144,12 +144,15 @@ dtt_init (void)
 	unsigned char sensors[] = CONFIG_DTT_SENSORS;
 	const char *const header = "DTT:   ";
 
+	/* switch to correct I2C bus */
+	I2C_SET_BUS(CFG_DTT_BUS_NUM);
+
 	for (i = 0; i < sizeof(sensors); i++) {
-	    if (_dtt_init(sensors[i]) != 0)
-		printf ("%s%d FAILED INIT\n", header, i+1);
-	    else
-		printf ("%s%d is %i C\n", header, i+1,
-		       dtt_get_temp(sensors[i]));
+		if (_dtt_init(sensors[i]) != 0)
+			printf ("%s%d FAILED INIT\n", header, i+1);
+		else
+			printf ("%s%d is %i C\n", header, i+1,
+				dtt_get_temp(sensors[i]));
 	}
 
 	return (0);