[PATCH 0/6] i2c: mux: mlxcpld: Extend driver functionality and update licenses

[PATCH 0/6] i2c: mux: mlxcpld: Extend driver functionality and update licenses

[Vadim Pasternak]

The patchset adds new features for the existing Mellanox systems.

Patches #1-#2 update license to SPDX-License.
Patch #3  moves header file out of x86 realm.
Patch #4 converts driver to platform driver.
Patch #5 adds support for word address space devices.
Patch #6 extends mux number supported by driver.

Vadim Pasternak (6):
  i2c: mux: mlxcpld: Update module license
  platform/x86: mlxcpld: Update module license
  i2c: mux: mlxcpld: Move header file out of x86 realm
  i2c: mux: mlxcpld: Convert driver to platform driver
  i2c: mux: mlxcpld: Extend driver to support word address space devices
  i2c: mux: mlxcpld: Extend supported mux number

 drivers/i2c/muxes/i2c-mux-mlxcpld.c       | 153 ++++++++++++++----------------
 include/linux/platform_data/mlxcpld.h     |  26 +++++
 include/linux/platform_data/x86/mlxcpld.h |  52 ----------
 3 files changed, 99 insertions(+), 132 deletions(-)
 create mode 100644 include/linux/platform_data/mlxcpld.h
 delete mode 100644 include/linux/platform_data/x86/mlxcpld.h

-- 
2.11.0

[PATCH 1/6] i2c: mux: mlxcpld: Update module license

[Vadim Pasternak]

Update license to SPDX-License.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
---
 drivers/i2c/muxes/i2c-mux-mlxcpld.c | 33 +++------------------------------
 1 file changed, 3 insertions(+), 30 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index 5ed55ca4fe93..53bce81cf5c9 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -1,35 +1,8 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 /*
- * drivers/i2c/muxes/i2c-mux-mlxcpld.c
- * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
- * Copyright (c) 2016 Michael Shych <michaels@mellanox.com>
+ * Mellanox i2c mux driver
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the names of the copyright holders nor the names of its
- *    contributors may be used to endorse or promote products derived from
- *    this software without specific prior written permission.
- *
- * Alternatively, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") version 2 as published by the Free
- * Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
+ * Copyright (C) 2016-2020 Mellanox Technologies
  */
 
 #include <linux/device.h>
-- 
2.11.0

[PATCH 2/6] platform/x86: mlxcpld: Update module license

[Vadim Pasternak]

Update license to SPDX-License.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
---
 include/linux/platform_data/x86/mlxcpld.h | 34 +++----------------------------
 1 file changed, 3 insertions(+), 31 deletions(-)

diff --git a/include/linux/platform_data/x86/mlxcpld.h b/include/linux/platform_data/x86/mlxcpld.h
index b08dcb183fca..e6c18bf017dd 100644
--- a/include/linux/platform_data/x86/mlxcpld.h
+++ b/include/linux/platform_data/x86/mlxcpld.h
@@ -1,36 +1,8 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
 /*
- * mlxcpld.h - Mellanox I2C multiplexer support in CPLD
+ * Mellanox I2C multiplexer support in CPLD
  *
- * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
- * Copyright (c) 2016 Michael Shych <michaels@mellanox.com>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the names of the copyright holders nor the names of its
- *    contributors may be used to endorse or promote products derived from
- *    this software without specific prior written permission.
- *
- * Alternatively, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") version 2 as published by the Free
- * Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
+ * Copyright (C) 2016-2020 Mellanox Technologies
  */
 
 #ifndef _LINUX_I2C_MLXCPLD_H
-- 
2.11.0

[PATCH 3/6] i2c: mux: mlxcpld: Move header file out of x86 realm

[Vadim Pasternak]

Move out header file from include/linux/platform_data/x86/ to
include/linux/platform_data/, since it does not depend on x86
architecture.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
---
 drivers/i2c/muxes/i2c-mux-mlxcpld.c             | 2 +-
 include/linux/platform_data/{x86 => }/mlxcpld.h | 0
 2 files changed, 1 insertion(+), 1 deletion(-)
 rename include/linux/platform_data/{x86 => }/mlxcpld.h (100%)

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index 53bce81cf5c9..3d894cfb19df 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -11,7 +11,7 @@
 #include <linux/io.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/platform_data/x86/mlxcpld.h>
+#include <linux/platform_data/mlxcpld.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
diff --git a/include/linux/platform_data/x86/mlxcpld.h b/include/linux/platform_data/mlxcpld.h
similarity index 100%
rename from include/linux/platform_data/x86/mlxcpld.h
rename to include/linux/platform_data/mlxcpld.h
-- 
2.11.0

[PATCH 4/6] i2c: mux: mlxcpld: Convert driver to platform driver

[Vadim Pasternak]

Convert driver from 'i2c' to 'platform'.
The motivation is to avoid I2C addressing conflict between
‘i2c-mux-cpld’ driver, providing mux selection and deselection through
CPLD ‘mux control’ register, and CPLD host driver. The CPLD is I2C
device and is multi-functional device performing logic for different
components, like LED, ‘hwmon’, interrupt control, watchdog etcetera.
For such configuration CPLD should be host I2C device, connected to the
relevant I2C bus with the relevant I2C address and all others component
drivers are supposed to be its children.
The hierarchy in such case will be like in the below example:
ls /sys/bus/i2c/devices/44-0032
i2c-mux-mlxcpld.44  leds-mlxreg.44  mlxreg-io.44
ls /sys/bus/i2c/devices/44-0032/i2c-mux-mlxcpld.44
channel-0, …,  channel-X

Currently this driver is not activated by any kernel driver,
so this conversion doesn’t affect any user.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
---
 drivers/i2c/muxes/i2c-mux-mlxcpld.c | 62 +++++++++++++++++--------------------
 1 file changed, 28 insertions(+), 34 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index 3d894cfb19df..6bb8caecf8e8 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -20,10 +20,12 @@
 /* mlxcpld_mux - mux control structure:
  * @last_chan - last register value
  * @client - I2C device client
+ * @pdata: platform data
  */
 struct mlxcpld_mux {
 	u8 last_chan;
 	struct i2c_client *client;
+	struct mlxcpld_mux_plat_data pdata;
 };
 
 /* MUX logic description.
@@ -54,37 +56,30 @@ struct mlxcpld_mux {
  *
  */
 
-static const struct i2c_device_id mlxcpld_mux_id[] = {
-	{ "mlxcpld_mux_module", 0 },
-	{ }
-};
-MODULE_DEVICE_TABLE(i2c, mlxcpld_mux_id);
-
 /* Write to mux register. Don't use i2c_transfer() and i2c_smbus_xfer()
  * for this as they will try to lock adapter a second time.
  */
 static int mlxcpld_mux_reg_write(struct i2c_adapter *adap,
-				 struct i2c_client *client, u8 val)
+				 struct mlxcpld_mux *mux, u8 val)
 {
-	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+	struct i2c_client *client = mux->client;
 	union i2c_smbus_data data = { .byte = val };
 
 	return __i2c_smbus_xfer(adap, client->addr, client->flags,
-				I2C_SMBUS_WRITE, pdata->sel_reg_addr,
+				I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr,
 				I2C_SMBUS_BYTE_DATA, &data);
 }
 
 static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
 {
-	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
-	struct i2c_client *client = data->client;
+	struct mlxcpld_mux *mux = i2c_mux_priv(muxc);
 	u8 regval = chan + 1;
 	int err = 0;
 
 	/* Only select the channel if its different from the last channel */
-	if (data->last_chan != regval) {
-		err = mlxcpld_mux_reg_write(muxc->parent, client, regval);
-		data->last_chan = err < 0 ? 0 : regval;
+	if (mux->last_chan != regval) {
+		err = mlxcpld_mux_reg_write(muxc->parent, mux, regval);
+		mux->last_chan = err < 0 ? 0 : regval;
 	}
 
 	return err;
@@ -92,21 +87,19 @@ static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
 
 static int mlxcpld_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
 {
-	struct mlxcpld_mux *data = i2c_mux_priv(muxc);
-	struct i2c_client *client = data->client;
+	struct mlxcpld_mux *mux = i2c_mux_priv(muxc);
 
 	/* Deselect active channel */
-	data->last_chan = 0;
+	mux->last_chan = -1;
 
-	return mlxcpld_mux_reg_write(muxc->parent, client, data->last_chan);
+	return mlxcpld_mux_reg_write(muxc->parent, mux, mux->last_chan);
 }
 
 /* Probe/reomove functions */
-static int mlxcpld_mux_probe(struct i2c_client *client,
-			     const struct i2c_device_id *id)
+static int mlxcpld_mux_probe(struct platform_device *pdev)
 {
-	struct i2c_adapter *adap = client->adapter;
-	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&client->dev);
+	struct mlxcpld_mux_plat_data *pdata = dev_get_platdata(&pdev->dev);
+	struct i2c_client *client = to_i2c_client(pdev->dev.parent);
 	struct i2c_mux_core *muxc;
 	int num, force;
 	struct mlxcpld_mux *data;
@@ -115,18 +108,20 @@ static int mlxcpld_mux_probe(struct i2c_client *client,
 	if (!pdata)
 		return -EINVAL;
 
-	if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
 		return -ENODEV;
 
-	muxc = i2c_mux_alloc(adap, &client->dev, CPLD_MUX_MAX_NCHANS,
+	muxc = i2c_mux_alloc(client->adapter, &pdev->dev, CPLD_MUX_MAX_NCHANS,
 			     sizeof(*data), 0, mlxcpld_mux_select_chan,
 			     mlxcpld_mux_deselect);
 	if (!muxc)
 		return -ENOMEM;
 
+	platform_set_drvdata(pdev, muxc);
 	data = i2c_mux_priv(muxc);
-	i2c_set_clientdata(client, muxc);
 	data->client = client;
+	memcpy(&data->pdata, pdata, sizeof(*pdata));
 	data->last_chan = 0; /* force the first selection */
 
 	/* Create an adapter for each channel. */
@@ -149,24 +144,23 @@ static int mlxcpld_mux_probe(struct i2c_client *client,
 	return err;
 }
 
-static int mlxcpld_mux_remove(struct i2c_client *client)
+static int mlxcpld_mux_remove(struct platform_device *pdev)
 {
-	struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+	struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
 
 	i2c_mux_del_adapters(muxc);
 	return 0;
 }
 
-static struct i2c_driver mlxcpld_mux_driver = {
-	.driver		= {
-		.name	= "mlxcpld-mux",
+static struct platform_driver mlxcpld_mux_driver = {
+	.driver = {
+		.name = "i2c-mux-mlxcpld",
 	},
-	.probe		= mlxcpld_mux_probe,
-	.remove		= mlxcpld_mux_remove,
-	.id_table	= mlxcpld_mux_id,
+	.probe = mlxcpld_mux_probe,
+	.remove = mlxcpld_mux_remove,
 };
 
-module_i2c_driver(mlxcpld_mux_driver);
+module_platform_driver(mlxcpld_mux_driver);
 
 MODULE_AUTHOR("Michael Shych (michaels@mellanox.com)");
 MODULE_DESCRIPTION("Mellanox I2C-CPLD-MUX driver");
-- 
2.11.0

[PATCH 5/6] i2c: mux: mlxcpld: Extend driver to support word address space devices

[Vadim Pasternak]

Extend driver to allow I2C routing control through CPLD devices with
word address space. Till now only CPLD devices with byte address space
have been supported.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
---
 drivers/i2c/muxes/i2c-mux-mlxcpld.c   | 57 +++++++++++++++++++++++++++--------
 include/linux/platform_data/mlxcpld.h |  2 ++
 2 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index 6bb8caecf8e8..c76180919fc3 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -21,11 +21,13 @@
  * @last_chan - last register value
  * @client - I2C device client
  * @pdata: platform data
+ * @sel_buf: I2C message buffer for mux select 16 bits transactions
  */
 struct mlxcpld_mux {
 	u8 last_chan;
 	struct i2c_client *client;
 	struct mlxcpld_mux_plat_data pdata;
+	u8 sel_buf[3];
 };
 
 /* MUX logic description.
@@ -60,26 +62,42 @@ struct mlxcpld_mux {
  * for this as they will try to lock adapter a second time.
  */
 static int mlxcpld_mux_reg_write(struct i2c_adapter *adap,
-				 struct mlxcpld_mux *mux, u8 val)
+				 struct mlxcpld_mux *mux, int chan)
 {
 	struct i2c_client *client = mux->client;
-	union i2c_smbus_data data = { .byte = val };
-
-	return __i2c_smbus_xfer(adap, client->addr, client->flags,
-				I2C_SMBUS_WRITE, mux->pdata.sel_reg_addr,
-				I2C_SMBUS_BYTE_DATA, &data);
+	union i2c_smbus_data data;
+	struct i2c_msg msg;
+
+	switch (mux->pdata.reg_size) {
+	case 1:
+		data.byte = (chan < 0) ? 0 : chan;
+		return __i2c_smbus_xfer(adap, client->addr, client->flags,
+					I2C_SMBUS_WRITE,
+					mux->pdata.sel_reg_addr,
+					I2C_SMBUS_BYTE_DATA, &data);
+	case 2:
+		mux->sel_buf[mux->pdata.reg_size] = (chan < 0) ? 0 :
+						    mux->pdata.adap_ids[chan];
+		msg.addr = client->addr;
+		msg.buf = mux->sel_buf;
+		msg.len = mux->pdata.reg_size + 1;
+		msg.flags = 0;
+		return __i2c_transfer(adap, &msg, 1);
+	default:
+		return -EINVAL;
+	}
 }
 
 static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
 {
 	struct mlxcpld_mux *mux = i2c_mux_priv(muxc);
-	u8 regval = chan + 1;
 	int err = 0;
 
 	/* Only select the channel if its different from the last channel */
-	if (mux->last_chan != regval) {
-		err = mlxcpld_mux_reg_write(muxc->parent, mux, regval);
-		mux->last_chan = err < 0 ? 0 : regval;
+	chan++;
+	if (mux->last_chan != chan) {
+		err = mlxcpld_mux_reg_write(muxc->parent, mux, chan);
+		mux->last_chan = err < 0 ? 0 : chan;
 	}
 
 	return err;
@@ -103,13 +121,26 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
 	struct i2c_mux_core *muxc;
 	int num, force;
 	struct mlxcpld_mux *data;
+	u16 sel_reg_addr = 0;
+	u32 func;
 	int err;
 
 	if (!pdata)
 		return -EINVAL;
 
-	if (!i2c_check_functionality(client->adapter,
-				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+	switch (pdata->reg_size) {
+	case 1:
+		func = I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+		break;
+	case 2:
+		func = I2C_FUNC_SMBUS_WRITE_WORD_DATA;
+		sel_reg_addr = cpu_to_be16(pdata->sel_reg_addr);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(client->adapter, func))
 		return -ENODEV;
 
 	muxc = i2c_mux_alloc(client->adapter, &pdev->dev, CPLD_MUX_MAX_NCHANS,
@@ -122,6 +153,8 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
 	data = i2c_mux_priv(muxc);
 	data->client = client;
 	memcpy(&data->pdata, pdata, sizeof(*pdata));
+	/* Save mux select address for 16 bits transaction size. */
+	memcpy(data->sel_buf, &sel_reg_addr, 2);
 	data->last_chan = 0; /* force the first selection */
 
 	/* Create an adapter for each channel. */
diff --git a/include/linux/platform_data/mlxcpld.h b/include/linux/platform_data/mlxcpld.h
index e6c18bf017dd..da4f7e8f5721 100644
--- a/include/linux/platform_data/mlxcpld.h
+++ b/include/linux/platform_data/mlxcpld.h
@@ -14,11 +14,13 @@
  * @adap_ids - adapter array
  * @num_adaps - number of adapters
  * @sel_reg_addr - mux select register offset in CPLD space
+ * @reg_size: register size in bytes (default 0 - 1 byte data, 1 - 2 bytes data
  */
 struct mlxcpld_mux_plat_data {
 	int *adap_ids;
 	int num_adaps;
 	int sel_reg_addr;
+	u8 reg_size;
 };
 
 #endif /* _LINUX_I2C_MLXCPLD_H */
-- 
2.11.0

[PATCH 6/6] i2c: mux: mlxcpld: Extend supported mux number

[Vadim Pasternak]

Allow to extend mux number supported by driver.
Currently it is limited by eight, which is not enough for new coming
Mellanox modular system with line cards, which require up to 64 mux
support.

Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Michael Shych <michaelsh@nvidia.com>
---
 drivers/i2c/muxes/i2c-mux-mlxcpld.c | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-mlxcpld.c b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
index c76180919fc3..760636b507fa 100644
--- a/drivers/i2c/muxes/i2c-mux-mlxcpld.c
+++ b/drivers/i2c/muxes/i2c-mux-mlxcpld.c
@@ -15,8 +15,6 @@
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 
-#define CPLD_MUX_MAX_NCHANS	8
-
 /* mlxcpld_mux - mux control structure:
  * @last_chan - last register value
  * @client - I2C device client
@@ -24,7 +22,7 @@
  * @sel_buf: I2C message buffer for mux select 16 bits transactions
  */
 struct mlxcpld_mux {
-	u8 last_chan;
+	int last_chan;
 	struct i2c_client *client;
 	struct mlxcpld_mux_plat_data pdata;
 	u8 sel_buf[3];
@@ -94,7 +92,6 @@ static int mlxcpld_mux_select_chan(struct i2c_mux_core *muxc, u32 chan)
 	int err = 0;
 
 	/* Only select the channel if its different from the last channel */
-	chan++;
 	if (mux->last_chan != chan) {
 		err = mlxcpld_mux_reg_write(muxc->parent, mux, chan);
 		mux->last_chan = err < 0 ? 0 : chan;
@@ -143,7 +140,7 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
 	if (!i2c_check_functionality(client->adapter, func))
 		return -ENODEV;
 
-	muxc = i2c_mux_alloc(client->adapter, &pdev->dev, CPLD_MUX_MAX_NCHANS,
+	muxc = i2c_mux_alloc(client->adapter, &pdev->dev, pdata->num_adaps,
 			     sizeof(*data), 0, mlxcpld_mux_select_chan,
 			     mlxcpld_mux_deselect);
 	if (!muxc)
@@ -158,13 +155,9 @@ static int mlxcpld_mux_probe(struct platform_device *pdev)
 	data->last_chan = 0; /* force the first selection */
 
 	/* Create an adapter for each channel. */
-	for (num = 0; num < CPLD_MUX_MAX_NCHANS; num++) {
-		if (num >= pdata->num_adaps)
-			/* discard unconfigured channels */
-			break;
-
-		force = pdata->adap_ids[num];
-
+	for (num = 0; num < pdata->num_adaps; num++) {
+		force = pdata->base_nr ? (pdata->base_nr +
+			pdata->adap_ids[num]) : pdata->adap_ids[num];
 		err = i2c_mux_add_adapter(muxc, force, num, 0);
 		if (err)
 			goto virt_reg_failed;
-- 
2.11.0