[U-Boot] [PATCH] powerpc/t4240qds: add support of reading Core voltage

[shh.xie at gmail.com]

From: Shaohui Xie <Shaohui.Xie at freescale.com>

A U-boot CMD vdd_read is implemented to read Core voltage.

Signed-off-by: Shaohui Xie <Shaohui.Xie at freescale.com>
---
 board/freescale/t4qds/t4240qds.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/board/freescale/t4qds/t4240qds.c b/board/freescale/t4qds/t4240qds.c
index 4f2cccd..56273e4 100644
--- a/board/freescale/t4qds/t4240qds.c
+++ b/board/freescale/t4qds/t4240qds.c
@@ -887,8 +887,38 @@ static int do_vdd_adjust(cmd_tbl_t *cmdtp,
 	return 0;
 }
 
+static int do_vdd_read(cmd_tbl_t *cmdtp,
+		       int flag, int argc,
+		       char * const argv[])
+{
+	int vdd, ret;
+
+	if (argc < 1)
+		return CMD_RET_USAGE;
+
+	ret = select_i2c_ch_pca9547(I2C_MUX_CH_VOL_MONITOR);
+	if (ret) {
+		printf("VID: I2c failed to switch channel\n");
+		return 0;
+	}
+
+	vdd = read_voltage();
+	if (vdd < 0)
+		printf("VID: Could not read voltage\n");
+	else
+		printf("VID: Core voltage is at %d mV\n", vdd);
+
+	return 0;
+}
+
 U_BOOT_CMD(
 	vdd_override, 2, 0, do_vdd_adjust,
 	"Override VDD",
 	"- override with the voltage specified in mV, eg. 1050"
 );
+
+U_BOOT_CMD(
+	vdd_read, 1, 0, do_vdd_read,
+	"read VDD",
+	" - Read the voltage specified in mV"
+)
-- 
2.1.0.27.g96db324