diff mbox

[RFC,01/21] mfd: uniphier: add UniPhier MFD driver

Message ID 1462873862-30940-2-git-send-email-yamada.masahiro@socionext.com
State New
Headers show

Commit Message

Masahiro Yamada May 10, 2016, 9:50 a.m. UTC 
This MFD driver populates child devices such clock, reset, and other
system controlling blocks.

On UniPhier SoCs, one system control block contains various registers
for clock, reset, and others in it.  So, it is not reasonable to have
separate DT nodes for different sub-systems.

This MFD approach modifies Device Tree source just once for adding
an MFD node.

This series is just for review.
Please do not apply this patch.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

---

 MAINTAINERS                |   1 +
 drivers/mfd/Kconfig        |   9 ++
 drivers/mfd/Makefile       |   1 +
 drivers/mfd/uniphier-mfd.c | 214 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 225 insertions(+)
 create mode 100644 drivers/mfd/uniphier-mfd.c

-- 
1.9.1

Comments

Lee Jones May 10, 2016, 11:26 a.m. UTC | #1 
On Tue, 10 May 2016, Masahiro Yamada wrote:

> This MFD driver populates child devices such clock, reset, and other

> system controlling blocks.

> 

> On UniPhier SoCs, one system control block contains various registers

> for clock, reset, and others in it.  So, it is not reasonable to have

> separate DT nodes for different sub-systems.

> 

> This MFD approach modifies Device Tree source just once for adding

> an MFD node.

> 

> This series is just for review.

> Please do not apply this patch.

> 

> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

> ---

> 

>  MAINTAINERS                |   1 +

>  drivers/mfd/Kconfig        |   9 ++

>  drivers/mfd/Makefile       |   1 +

>  drivers/mfd/uniphier-mfd.c | 214 +++++++++++++++++++++++++++++++++++++++++++++

>  4 files changed, 225 insertions(+)

>  create mode 100644 drivers/mfd/uniphier-mfd.c

> 

> diff --git a/MAINTAINERS b/MAINTAINERS

> index 87b2ddd..8c987ca 100644

> --- a/MAINTAINERS

> +++ b/MAINTAINERS

> @@ -1728,6 +1728,7 @@ F:	arch/arm/mm/cache-uniphier.c

>  F:	arch/arm64/boot/dts/socionext/

>  F:	drivers/bus/uniphier-system-bus.c

>  F:	drivers/i2c/busses/i2c-uniphier*

> +F:	drivers/mfd/uniphier-mfd.c

>  F:	drivers/mmc/host/uniphier-sd.c

>  F:	drivers/pinctrl/uniphier/

>  F:	drivers/tty/serial/8250/8250_uniphier.c

> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig

> index eea61e3..ea85862 100644

> --- a/drivers/mfd/Kconfig

> +++ b/drivers/mfd/Kconfig

> @@ -892,6 +892,15 @@ config MFD_SKY81452

>  	  This driver can also be built as a module.  If so, the module

>  	  will be called sky81452.

>  

> +config MFD_UNIPHIER

> +	tristate "Socionext UniPhier MFD"

> +	depends on ARCH_UNIPHIER || COMPILE_TEST

> +	default ARCH_UNIPHIER

> +	select MFD_CORE

> +	help

> +	  Support for the System Control Block, Media I/O Control Block,

> +	  Peripheral Control Block available on UniPhier SoCs.

> +

>  config MFD_SMSC

>         bool "SMSC ECE1099 series chips"

>         depends on I2C=y

> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile

> index 5eaa6465d..5e8c20c 100644

> --- a/drivers/mfd/Makefile

> +++ b/drivers/mfd/Makefile

> @@ -198,6 +198,7 @@ obj-$(CONFIG_MFD_HI6421_PMIC)	+= hi6421-pmic-core.o

>  obj-$(CONFIG_MFD_DLN2)		+= dln2.o

>  obj-$(CONFIG_MFD_RT5033)	+= rt5033.o

>  obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o

> +obj-$(CONFIG_MFD_UNIPHIER)	+= uniphier-mfd.o

>  

>  intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o

>  intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)	+= intel_soc_pmic_bxtwc.o

> diff --git a/drivers/mfd/uniphier-mfd.c b/drivers/mfd/uniphier-mfd.c

> new file mode 100644

> index 0000000..7f01d64

> --- /dev/null

> +++ b/drivers/mfd/uniphier-mfd.c

> @@ -0,0 +1,214 @@

> +/*

> + * Copyright (C) 2016 Socionext Inc.

> + *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>

> + *

> + * 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.

> + *

> + * This program is distributed in the hope that it will be useful,

> + * but WITHOUT ANY WARRANTY; without even the implied warranty of

> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

> + * GNU General Public License for more details.

> + */

> +

> +#include <linux/mfd/core.h>

> +#include <linux/module.h>

> +#include <linux/of.h>

> +#include <linux/platform_device.h>

> +

> +static const struct mfd_cell uniphier_ld4_sysctrl_cells[] = {

> +	{ .name = "uniphier-ld4-clk" },

> +	{ .name = "uniphier-ld4-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_pro4_sysctrl_cells[] = {

> +	{ .name = "uniphier-pro4-clk" },

> +	{ .name = "uniphier-pro4-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_sld8_sysctrl_cells[] = {

> +	{ .name = "uniphier-sld8-clk" },

> +	{ .name = "uniphier-sld8-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_pro5_sysctrl_cells[] = {

> +	{ .name = "uniphier-pro5-clk" },

> +	{ .name = "uniphier-pro5-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_pxs2_sysctrl_cells[] = {

> +	{ .name = "uniphier-pxs2-clk" },

> +	{ .name = "uniphier-pxs2-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_ld11_sysctrl_cells[] = {

> +	{ .name = "uniphier-ld11-clk" },

> +	{ .name = "uniphier-ld11-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_ld20_sysctrl_cells[] = {

> +	{ .name = "uniphier-ld20-clk" },

> +	{ .name = "uniphier-ld20-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_ld4_mioctrl_cells[] = {

> +	{ .name = "uniphier-ld4-mio-clk" },

> +	{ .name = "uniphier-ld4-mio-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_pro5_mioctrl_cells[] = {

> +	{ .name = "uniphier-pro5-mio-clk" },

> +	{ .name = "uniphier-pro5-mio-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_ld4_perictrl_cells[] = {

> +	{ .name = "uniphier-ld4-peri-clk" },

> +	{ .name = "uniphier-ld4-peri-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct mfd_cell uniphier_pro4_perictrl_cells[] = {

> +	{ .name = "uniphier-pro4-peri-clk" },

> +	{ .name = "uniphier-pro4-peri-reset" },

> +	{ /* sentinel */ }

> +};

> +

> +static const struct of_device_id uniphier_mfd_match[] = {

> +	/* System Control */

> +	{

> +		.compatible = "socionext,uniphier-ld4-sysctrl",

> +		.data = uniphier_ld4_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro4-sysctrl",

> +		.data = uniphier_pro4_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-sld8-sysctrl",

> +		.data = uniphier_sld8_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro5-sysctrl",

> +		.data = uniphier_pro5_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pxs2-sysctrl",

> +		.data = uniphier_pxs2_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld11-sysctrl",

> +		.data = uniphier_ld11_sysctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld20-sysctrl",

> +		.data = uniphier_ld20_sysctrl_cells,

> +	},

> +	/* Media I/O */

> +	{

> +		.compatible = "socionext,uniphier-ld4-mioctrl",

> +		.data = uniphier_ld4_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro4-mioctrl",

> +		.data = uniphier_ld4_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-sld8-mioctrl",

> +		.data = uniphier_ld4_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro5-mioctrl",

> +		.data = uniphier_pro5_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pxs2-mioctrl",

> +		.data = uniphier_pro5_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld11-mioctrl",

> +		.data = uniphier_ld4_mioctrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld20-mioctrl",

> +		.data = uniphier_pro5_mioctrl_cells,

> +	},

> +	/* Peripheral Control */

> +	{

> +		.compatible = "socionext,uniphier-ld4-perictrl",

> +		.data = uniphier_ld4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-sld8-perictrl",

> +		.data = uniphier_ld4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro4-perictrl",

> +		.data = uniphier_pro4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pro5-perictrl",

> +		.data = uniphier_pro4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-pxs2-perictrl",

> +		.data = uniphier_pro4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld11-perictrl",

> +		.data = uniphier_pro4_perictrl_cells,

> +	},

> +	{

> +		.compatible = "socionext,uniphier-ld20-perictrl",

> +		.data = uniphier_pro4_perictrl_cells,

> +	},

> +	{ /* sentinel */ }

> +};

> +MODULE_DEVICE_TABLE(of, uniphier_mfd_match);


NACK.  Please do not mix MFD and DT registration.

> +static int uniphier_mfd_probe(struct platform_device *pdev)

> +{

> +	const struct of_device_id *match;

> +	const struct mfd_cell *cell;

> +	int ret;

> +	int n_cells = 0;

> +

> +	match = of_match_node(uniphier_mfd_match, pdev->dev.of_node);

> +	if (!match)

> +		return -ENODEV;

> +

> +	cell = match->data;

> +

> +	for (; cell->name; cell++)

> +		n_cells++;

> +

> +	ret = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, match->data,

> +			      n_cells, NULL, 0, NULL);

> +	if (ret)

> +		dev_err(&pdev->dev, "failed to add MFD devices\n");

> +

> +	return ret;

> +}


This driver is not required.

I think you just need to use "simple-mfd".

> +static struct platform_driver uniphier_mfd_driver = {

> +	.probe = uniphier_mfd_probe,

> +	.driver = {

> +		.name = "uniphier-mfd",

> +		.of_match_table = uniphier_mfd_match,

> +	},

> +};

> +module_platform_driver(uniphier_mfd_driver);

> +

> +MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");

> +MODULE_DESCRIPTION("UniPhier SoC MFD Driver");

> +MODULE_LICENSE("GPL");


-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
Masahiro Yamada May 11, 2016, 1:51 a.m. UTC | #2 
Hi Lee,

2016-05-10 20:26 GMT+09:00 Lee Jones <lee.jones@linaro.org>:
>> +};

>> +MODULE_DEVICE_TABLE(of, uniphier_mfd_match);

>

> NACK.  Please do not mix MFD and DT registration.


OK, thanks for review.


My basic thought was:

  - Add an MFD node to my DTS only once.
    If I need to expand it in the future, I will just
    need to modify drivers/mtd/uniphier-mfd.c.
    It is just kernel-internal modification, so it does not
    bother DT binding at all.

  - Simplify the node topology of DTS.

-- 
Best Regards
Masahiro Yamada
Lee Jones May 11, 2016, 7:38 a.m. UTC | #3 
On Wed, 11 May 2016, Masahiro Yamada wrote:

> Hi Lee,

> 

> 2016-05-10 20:26 GMT+09:00 Lee Jones <lee.jones@linaro.org>:

> >> +};

> >> +MODULE_DEVICE_TABLE(of, uniphier_mfd_match);

> >

> > NACK.  Please do not mix MFD and DT registration.

> 

> OK, thanks for review.

> 

> 

> My basic thought was:

> 

>   - Add an MFD node to my DTS only once.

>     If I need to expand it in the future, I will just

>     need to modify drivers/mtd/uniphier-mfd.c.

>     It is just kernel-internal modification, so it does not

>     bother DT binding at all.

> 

>   - Simplify the node topology of DTS.


Just describe the hardware in DT.  If you do so accurately, there
should be no requirement to change it (in theory).

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
diff mbox

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 87b2ddd..8c987ca 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1728,6 +1728,7 @@  F:	arch/arm/mm/cache-uniphier.c
 F:	arch/arm64/boot/dts/socionext/
 F:	drivers/bus/uniphier-system-bus.c
 F:	drivers/i2c/busses/i2c-uniphier*
+F:	drivers/mfd/uniphier-mfd.c
 F:	drivers/mmc/host/uniphier-sd.c
 F:	drivers/pinctrl/uniphier/
 F:	drivers/tty/serial/8250/8250_uniphier.c
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index eea61e3..ea85862 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -892,6 +892,15 @@  config MFD_SKY81452
 	  This driver can also be built as a module.  If so, the module
 	  will be called sky81452.
 
+config MFD_UNIPHIER
+	tristate "Socionext UniPhier MFD"
+	depends on ARCH_UNIPHIER || COMPILE_TEST
+	default ARCH_UNIPHIER
+	select MFD_CORE
+	help
+	  Support for the System Control Block, Media I/O Control Block,
+	  Peripheral Control Block available on UniPhier SoCs.
+
 config MFD_SMSC
        bool "SMSC ECE1099 series chips"
        depends on I2C=y
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5eaa6465d..5e8c20c 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -198,6 +198,7 @@  obj-$(CONFIG_MFD_HI6421_PMIC)	+= hi6421-pmic-core.o
 obj-$(CONFIG_MFD_DLN2)		+= dln2.o
 obj-$(CONFIG_MFD_RT5033)	+= rt5033.o
 obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o
+obj-$(CONFIG_MFD_UNIPHIER)	+= uniphier-mfd.o
 
 intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
 intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)	+= intel_soc_pmic_bxtwc.o
diff --git a/drivers/mfd/uniphier-mfd.c b/drivers/mfd/uniphier-mfd.c
new file mode 100644
index 0000000..7f01d64
--- /dev/null
+++ b/drivers/mfd/uniphier-mfd.c
@@ -0,0 +1,214 @@ 
+/*
+ * Copyright (C) 2016 Socionext Inc.
+ *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+static const struct mfd_cell uniphier_ld4_sysctrl_cells[] = {
+	{ .name = "uniphier-ld4-clk" },
+	{ .name = "uniphier-ld4-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_pro4_sysctrl_cells[] = {
+	{ .name = "uniphier-pro4-clk" },
+	{ .name = "uniphier-pro4-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_sld8_sysctrl_cells[] = {
+	{ .name = "uniphier-sld8-clk" },
+	{ .name = "uniphier-sld8-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_pro5_sysctrl_cells[] = {
+	{ .name = "uniphier-pro5-clk" },
+	{ .name = "uniphier-pro5-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_pxs2_sysctrl_cells[] = {
+	{ .name = "uniphier-pxs2-clk" },
+	{ .name = "uniphier-pxs2-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_ld11_sysctrl_cells[] = {
+	{ .name = "uniphier-ld11-clk" },
+	{ .name = "uniphier-ld11-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_ld20_sysctrl_cells[] = {
+	{ .name = "uniphier-ld20-clk" },
+	{ .name = "uniphier-ld20-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_ld4_mioctrl_cells[] = {
+	{ .name = "uniphier-ld4-mio-clk" },
+	{ .name = "uniphier-ld4-mio-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_pro5_mioctrl_cells[] = {
+	{ .name = "uniphier-pro5-mio-clk" },
+	{ .name = "uniphier-pro5-mio-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_ld4_perictrl_cells[] = {
+	{ .name = "uniphier-ld4-peri-clk" },
+	{ .name = "uniphier-ld4-peri-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct mfd_cell uniphier_pro4_perictrl_cells[] = {
+	{ .name = "uniphier-pro4-peri-clk" },
+	{ .name = "uniphier-pro4-peri-reset" },
+	{ /* sentinel */ }
+};
+
+static const struct of_device_id uniphier_mfd_match[] = {
+	/* System Control */
+	{
+		.compatible = "socionext,uniphier-ld4-sysctrl",
+		.data = uniphier_ld4_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro4-sysctrl",
+		.data = uniphier_pro4_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-sld8-sysctrl",
+		.data = uniphier_sld8_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro5-sysctrl",
+		.data = uniphier_pro5_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-sysctrl",
+		.data = uniphier_pxs2_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld11-sysctrl",
+		.data = uniphier_ld11_sysctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-sysctrl",
+		.data = uniphier_ld20_sysctrl_cells,
+	},
+	/* Media I/O */
+	{
+		.compatible = "socionext,uniphier-ld4-mioctrl",
+		.data = uniphier_ld4_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro4-mioctrl",
+		.data = uniphier_ld4_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-sld8-mioctrl",
+		.data = uniphier_ld4_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro5-mioctrl",
+		.data = uniphier_pro5_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-mioctrl",
+		.data = uniphier_pro5_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld11-mioctrl",
+		.data = uniphier_ld4_mioctrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-mioctrl",
+		.data = uniphier_pro5_mioctrl_cells,
+	},
+	/* Peripheral Control */
+	{
+		.compatible = "socionext,uniphier-ld4-perictrl",
+		.data = uniphier_ld4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-sld8-perictrl",
+		.data = uniphier_ld4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro4-perictrl",
+		.data = uniphier_pro4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pro5-perictrl",
+		.data = uniphier_pro4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-perictrl",
+		.data = uniphier_pro4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld11-perictrl",
+		.data = uniphier_pro4_perictrl_cells,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-perictrl",
+		.data = uniphier_pro4_perictrl_cells,
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_mfd_match);
+
+static int uniphier_mfd_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	const struct mfd_cell *cell;
+	int ret;
+	int n_cells = 0;
+
+	match = of_match_node(uniphier_mfd_match, pdev->dev.of_node);
+	if (!match)
+		return -ENODEV;
+
+	cell = match->data;
+
+	for (; cell->name; cell++)
+		n_cells++;
+
+	ret = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO, match->data,
+			      n_cells, NULL, 0, NULL);
+	if (ret)
+		dev_err(&pdev->dev, "failed to add MFD devices\n");
+
+	return ret;
+}
+
+static struct platform_driver uniphier_mfd_driver = {
+	.probe = uniphier_mfd_probe,
+	.driver = {
+		.name = "uniphier-mfd",
+		.of_match_table = uniphier_mfd_match,
+	},
+};
+module_platform_driver(uniphier_mfd_driver);
+
+MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
+MODULE_DESCRIPTION("UniPhier SoC MFD Driver");
+MODULE_LICENSE("GPL");