board: freescale: Refactor NXP common mux code

Refactors similar mux code from multiple NXP boards into a common location,
and allows it to be disabled in config.

New config: CONFIG_FSL_USE_PCA9547_MUX to enable PCA9547 mux functionality.

Signed-off-by: Stephen Carlson <stcarlso@linux.microsoft.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>
diff --git a/board/freescale/common/Kconfig b/board/freescale/common/Kconfig
index 17db755..ab9c14a 100644
--- a/board/freescale/common/Kconfig
+++ b/board/freescale/common/Kconfig
@@ -21,6 +21,12 @@
 	    esbc_validate - validate signature using RSA verification
 	    esbc_halt - put the core in spin loop (Secure Boot Only)
 
+config FSL_USE_PCA9547_MUX
+	bool "Enable PCA9547 I2C Mux on Freescale boards"
+	default n
+	help
+	 This option enables the PCA9547 I2C mux on Freescale boards.
+
 config VID
 	depends on DM_I2C
 	bool "Enable Freescale VID"
diff --git a/board/freescale/common/Makefile b/board/freescale/common/Makefile
index 7862a79..116c1e7 100644
--- a/board/freescale/common/Makefile
+++ b/board/freescale/common/Makefile
@@ -15,6 +15,15 @@
 # necessary to create built-in.o
 obj- := __dummy__.o
 else
+# include i2c_common.o once if either VID or FSL_USE_PCA9547_MUX
+I2C_COMMON=
+ifdef CONFIG_VID
+I2C_COMMON=y
+endif
+ifdef CONFIG_FSL_USE_PCA9547_MUX
+I2C_COMMON=y
+endif
+
 obj-$(CONFIG_FSL_CADMUS)	+= cadmus.o
 obj-$(CONFIG_FSL_VIA)		+= cds_via.o
 obj-$(CONFIG_FMAN_ENET)	+= fman.o
@@ -22,6 +31,8 @@
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_FSL_NGPIXIS)	+= ngpixis.o
 endif
+obj-$(I2C_COMMON)		+= i2c_common.o
+obj-$(CONFIG_FSL_USE_PCA9547_MUX)		+= i2c_mux.o
 obj-$(CONFIG_VID)		+= vid.o
 obj-$(CONFIG_FSL_QIXIS)	+= qixis.o
 obj-$(CONFIG_PQ_MDS_PIB)	+= pq-mds-pib.o
diff --git a/board/freescale/common/i2c_common.c b/board/freescale/common/i2c_common.c
new file mode 100644
index 0000000..0f09ed7
--- /dev/null
+++ b/board/freescale/common/i2c_common.c
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ * Copyright 2020-21 NXP
+ * Copyright 2021 Microsoft Corporation
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include "i2c_common.h"
+
+#ifdef CONFIG_DM_I2C
+
+/* If DM is in use, retrieve the chip for the specified bus number */
+int fsl_i2c_get_device(int address, int bus, DEVICE_HANDLE_T *dev)
+{
+	int ret = i2c_get_chip_for_busnum(bus, address, 1, dev);
+
+	if (ret)
+		printf("I2C: Bus %d has no device with address 0x%02X\n",
+		       bus, address);
+	return ret;
+}
+
+#else
+
+/* Handle is passed directly */
+int fsl_i2c_get_device(int address, int bus, DEVICE_HANDLE_T *dev)
+{
+	*dev = address;
+	return 0;
+}
+
+#endif
diff --git a/board/freescale/common/i2c_common.h b/board/freescale/common/i2c_common.h
new file mode 100644
index 0000000..840ad66
--- /dev/null
+++ b/board/freescale/common/i2c_common.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ * Copyright 2020-21 NXP
+ * Copyright 2021 Microsoft Corporation
+ */
+
+#ifndef __NXP_I2C_COMMON_H__
+#define __NXP_I2C_COMMON_H__
+
+/* Common functionality shared by the I2C drivers for VID and the mux. */
+#ifdef CONFIG_DM_I2C
+#define DEVICE_HANDLE_T struct udevice *
+
+#define I2C_READ(dev, register, data, length) \
+	dm_i2c_read(dev, register, data, length)
+#define I2C_WRITE(dev, register, data, length) \
+	dm_i2c_write(dev, register, data, length)
+#else
+#define DEVICE_HANDLE_T int
+
+#define I2C_READ(dev, register, data, length) \
+	i2c_read(dev, register, 1, data, length)
+#define I2C_WRITE(dev, register, data, length) \
+	i2c_write(dev, register, 1, data, length)
+#endif
+
+int fsl_i2c_get_device(int address, int bus, DEVICE_HANDLE_T *dev);
+
+#endif
diff --git a/board/freescale/common/i2c_mux.c b/board/freescale/common/i2c_mux.c
new file mode 100644
index 0000000..54f89e2
--- /dev/null
+++ b/board/freescale/common/i2c_mux.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ * Copyright 2020-21 NXP
+ * Copyright 2021 Microsoft Corporation
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include "i2c_common.h"
+#include "i2c_mux.h"
+
+/*
+ * A new Kconfig option for something that used to always be built should be
+ * “default y”.
+ */
+#ifdef CONFIG_FSL_USE_PCA9547_MUX
+
+int select_i2c_ch_pca9547(u8 ch, int bus)
+{
+	int ret;
+	DEVICE_HANDLE_T dev;
+
+	/* Open device handle */
+	ret = fsl_i2c_get_device(I2C_MUX_PCA_ADDR_PRI, bus, &dev);
+	if (ret) {
+		printf("PCA: No PCA9547 device found\n");
+		return ret;
+	}
+
+	ret = I2C_WRITE(dev, 0, &ch, sizeof(ch));
+	if (ret) {
+		printf("PCA: Unable to select channel %d (%d)\n", (int)ch, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+#endif
diff --git a/board/freescale/common/i2c_mux.h b/board/freescale/common/i2c_mux.h
new file mode 100644
index 0000000..0870c19
--- /dev/null
+++ b/board/freescale/common/i2c_mux.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ * Copyright 2020-21 NXP
+ * Copyright 2021 Microsoft Corporation
+ */
+
+#ifndef __NXP_I2C_MUX_H__
+#define __NXP_I2C_MUX_H__
+
+#ifdef CONFIG_FSL_USE_PCA9547_MUX
+int select_i2c_ch_pca9547(u8 ch, int bus);
+#endif
+
+#endif
diff --git a/board/freescale/common/vid.c b/board/freescale/common/vid.c
index 13ef101..d2c9bbb 100644
--- a/board/freescale/common/vid.c
+++ b/board/freescale/common/vid.c
@@ -20,8 +20,13 @@
 #include <asm/immap_85xx.h>
 #endif
 #include <linux/delay.h>
+#include "i2c_common.h"
 #include "vid.h"
 
+#ifndef I2C_VOL_MONITOR_BUS
+#define I2C_VOL_MONITOR_BUS                    0
+#endif
+
 /* Voltages are generally handled in mV to keep them as integers */
 #define MV_PER_V 1000
 
@@ -95,44 +100,6 @@
 #define I2C_VOL_MONITOR_ADDR                    0
 #endif
 
-#if CONFIG_IS_ENABLED(DM_I2C)
-#define DEVICE_HANDLE_T struct udevice *
-
-#ifndef I2C_VOL_MONITOR_BUS
-#define I2C_VOL_MONITOR_BUS			0
-#endif
-
-/* If DM is in use, retrieve the udevice chip for the specified bus number */
-static int vid_get_device(int address, DEVICE_HANDLE_T *dev)
-{
-	int ret = i2c_get_chip_for_busnum(I2C_VOL_MONITOR_BUS, address, 1, dev);
-
-	if (ret)
-		printf("VID: Bus %d has no device with address 0x%02X\n",
-		       I2C_VOL_MONITOR_BUS, address);
-	return ret;
-}
-
-#define I2C_READ(dev, register, data, length) \
-	dm_i2c_read(dev, register, data, length)
-#define I2C_WRITE(dev, register, data, length) \
-	dm_i2c_write(dev, register, data, length)
-#else
-#define DEVICE_HANDLE_T int
-
-/* If DM is not in use, I2C addresses are passed directly */
-static int vid_get_device(int address, DEVICE_HANDLE_T *dev)
-{
-	*dev = address;
-	return 0;
-}
-
-#define I2C_READ(dev, register, data, length) \
-	i2c_read(dev, register, 1, data, length)
-#define I2C_WRITE(dev, register, data, length) \
-	i2c_write(dev, register, 1, data, length)
-#endif
-
 #if defined(CONFIG_VOL_MONITOR_IR36021_SET) || \
 	defined(CONFIG_VOL_MONITOR_IR36021_READ)
 /*
@@ -158,7 +125,7 @@
 	/* Check all the address */
 	for (i = 0; i < (sizeof(ir_i2c_addr)/sizeof(ir_i2c_addr[0])); i++) {
 		i2caddress = ir_i2c_addr[i];
-		ret = vid_get_device(i2caddress, &dev);
+		ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 		if (!ret) {
 			ret = I2C_READ(dev, IR36021_MFR_ID_OFFSET,
 				       (void *)&mfrID, sizeof(mfrID));
@@ -202,7 +169,7 @@
 	DEVICE_HANDLE_T dev;
 
 	/* Open device handle */
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -243,7 +210,7 @@
 	DEVICE_HANDLE_T dev;
 
 	/* Open device handle */
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -344,7 +311,7 @@
 	DEVICE_HANDLE_T dev;
 
 	/* Open device handle */
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -457,7 +424,7 @@
 	DEVICE_HANDLE_T dev;
 
 	/* Open device handle */
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -503,7 +470,7 @@
 	DEVICE_HANDLE_T dev;
 
 	/* Open device handle */
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -653,7 +620,7 @@
 		debug("VID: IR Chip found on I2C address 0x%02x\n", i2caddress);
 	}
 
-	ret = vid_get_device(i2caddress, &dev);
+	ret = fsl_i2c_get_device(i2caddress, I2C_VOL_MONITOR_BUS, &dev);
 	if (ret)
 		return ret;
 
@@ -785,7 +752,6 @@
 	i2c_multiplexer_select_vid_channel(I2C_MUX_CH_DEFAULT);
 
 	return ret < 0 ? -1 : 0;
-
 }
 
 static int do_vdd_override(struct cmd_tbl *cmdtp,