[v4,2/4] mfd: omap: control: core system control driver

Commit Message

Konstantin Baydarov July 25, 2012, 11:05 a.m. UTC

This patch introduces a MFD core device driver for
OMAP system control module.

The control module allows software control of
various static modes supported by the device. It is
composed of two control submodules: general control
module and device (padconfiguration) control
module.

Device driver is probed with postcore_initcall.
Control module register CONTROL_STATUS that is needed
by omap_type() is early mapped by postcore_initcall_sync.

Signed-off-by: J Keerthy <[e-mail]>
Signed-off-by: Kishon Vijay Abraham I <[e-mail]>
Signed-off-by: Eduardo Valentin <[e-mail]>
Signed-off-by: Konstantin Baydarov <[e-mail]>
---
 .../devicetree/bindings/mfd/omap_control.txt       |   32 ++++
 arch/arm/mach-omap2/Kconfig                        |    1 +
 arch/arm/plat-omap/Kconfig                         |    4 +
 drivers/mfd/Kconfig                                |    6 +
 drivers/mfd/Makefile                               |    1 +
 drivers/mfd/omap-control-core.c                    |  162 ++++++++++++++++++++
 include/linux/mfd/omap_control.h                   |   35 +++++
 7 files changed, 241 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mfd/omap_control.txt
 create mode 100644 drivers/mfd/omap-control-core.c
 create mode 100644 include/linux/mfd/omap_control.h

Comments

Felipe Balbi July 25, 2012, 11:07 a.m. UTC | #1

Hi,

On Wed, Jul 25, 2012 at 03:05:16PM +0400, Konstantin Baydarov wrote:
> This patch introduces a MFD core device driver for
> OMAP system control module.
> 
> The control module allows software control of
> various static modes supported by the device. It is
> composed of two control submodules: general control
> module and device (padconfiguration) control
> module.
> 
> Device driver is probed with postcore_initcall.
> Control module register CONTROL_STATUS that is needed
> by omap_type() is early mapped by postcore_initcall_sync.
> 
> Signed-off-by: J Keerthy <[e-mail]>
> Signed-off-by: Kishon Vijay Abraham I <[e-mail]>
> Signed-off-by: Eduardo Valentin <[e-mail]>
> Signed-off-by: Konstantin Baydarov <[e-mail]>

I believe this and the next 3 were authored by Eduardo. Also missing his
From tag.

Tony Lindgren Aug. 8, 2012, 2:05 p.m. UTC | #2

* Konstantin Baydarov <[e-mail]> [120725 04:10]:
> +
> +u32 omap_control_status_read(void)
> +{
> +	return __raw_readl(omap_control_base);
> +}

Ah OK it's changed here.. Sorry I was looking at the older
version.

> +void __init of_omap_control_init(const struct of_device_id *matches)
> +{
> +	struct device_node *np;
> +	struct property *pp = 0;
> +
> +	for_each_matching_node(np, matches) {
> +		pp = of_find_property(np, "reg", NULL);
> +		if(pp) {
> +			omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
> +			omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
> +			/*
> +			 * Map control module register CONTROL_STATUS register:
> +			 * omap24xx - OMAP24XX_CONTROL_STATUS
> +			 * am33xx   - AM33XX_CONTROL_STATUS
> +			 * omap34xx - OMAP343X_CONTROL_STATUS
> +			 * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
> +			 * omap54xx - OMAP5XXX_CONTROL_STATUS
> +			 */
> +			omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
> +		}
> +	}
> +}

You should probably add a function for setting omap_control_base
separately from *set_globals* in arch/arm/mach-omap2/common.c.
That way it's initialized early for id.c, and you can initialize
everything else later as regular device drivers.

FYI, we want to initialize as much as possible late so we have
proper debugging console set up in case things go wrong.

Regards,

Tony

Tony Lindgren Aug. 8, 2012, 2:10 p.m. UTC | #3

* Tony Lindgren <[e-mail]> [120808 07:05]:
> * Konstantin Baydarov <[e-mail]> [120725 04:10]:
> > +
> > +u32 omap_control_status_read(void)
> > +{
> > +	return __raw_readl(omap_control_base);
> > +}
> 
> Ah OK it's changed here.. Sorry I was looking at the older
> version.
> 
> > +void __init of_omap_control_init(const struct of_device_id *matches)
> > +{
> > +	struct device_node *np;
> > +	struct property *pp = 0;
> > +
> > +	for_each_matching_node(np, matches) {
> > +		pp = of_find_property(np, "reg", NULL);
> > +		if(pp) {
> > +			omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
> > +			omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
> > +			/*
> > +			 * Map control module register CONTROL_STATUS register:
> > +			 * omap24xx - OMAP24XX_CONTROL_STATUS
> > +			 * am33xx   - AM33XX_CONTROL_STATUS
> > +			 * omap34xx - OMAP343X_CONTROL_STATUS
> > +			 * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
> > +			 * omap54xx - OMAP5XXX_CONTROL_STATUS
> > +			 */
> > +			omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
> > +		}
> > +	}
> > +}
> 
> You should probably add a function for setting omap_control_base
> separately from *set_globals* in arch/arm/mach-omap2/common.c.
> That way it's initialized early for id.c, and you can initialize
> everything else later as regular device drivers.
> 
> FYI, we want to initialize as much as possible late so we have
> proper debugging console set up in case things go wrong.

Hmm it seems that omap_control_base is now only initialized for DT boot
case? This will break booting on almost all systems..

Tony

Tony Lindgren Aug. 8, 2012, 2:39 p.m. UTC | #4

* Tony Lindgren <[e-mail]> [120808 07:11]:
> * Tony Lindgren <[e-mail]> [120808 07:05]:
> > * Konstantin Baydarov <[e-mail]> [120725 04:10]:
> > > +
> > > +u32 omap_control_status_read(void)
> > > +{
> > > +	return __raw_readl(omap_control_base);
> > > +}
> > 
> > Ah OK it's changed here.. Sorry I was looking at the older
> > version.
> > 
> > > +void __init of_omap_control_init(const struct of_device_id *matches)
> > > +{
> > > +	struct device_node *np;
> > > +	struct property *pp = 0;
> > > +
> > > +	for_each_matching_node(np, matches) {
> > > +		pp = of_find_property(np, "reg", NULL);
> > > +		if(pp) {
> > > +			omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
> > > +			omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
> > > +			/*
> > > +			 * Map control module register CONTROL_STATUS register:
> > > +			 * omap24xx - OMAP24XX_CONTROL_STATUS
> > > +			 * am33xx   - AM33XX_CONTROL_STATUS
> > > +			 * omap34xx - OMAP343X_CONTROL_STATUS
> > > +			 * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
> > > +			 * omap54xx - OMAP5XXX_CONTROL_STATUS
> > > +			 */
> > > +			omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
> > > +		}
> > > +	}
> > > +}
> > 
> > You should probably add a function for setting omap_control_base
> > separately from *set_globals* in arch/arm/mach-omap2/common.c.
> > That way it's initialized early for id.c, and you can initialize
> > everything else later as regular device drivers.
> > 
> > FYI, we want to initialize as much as possible late so we have
> > proper debugging console set up in case things go wrong.
> 
> Hmm it seems that omap_control_base is now only initialized for DT boot
> case? This will break booting on almost all systems..

Looking at things more, looks like omap_type() is getting called
early from timer.c. So maybe just let set_globals initialize
omap_control_base and let omap_type() read that directly. That way
the SCM core driver can behave like a regular device driver and it
does not need to be initialized early.

Regards,

Tony

Konstantin Baydarov Aug. 8, 2012, 2:59 p.m. UTC | #5

Hi, Tony.

On 08/08/2012 06:39 PM, Tony Lindgren wrote:
> * Tony Lindgren <[e-mail]> [120808 07:11]:
>> * Tony Lindgren <[e-mail]> [120808 07:05]:
>>> * Konstantin Baydarov <[e-mail]> [120725 04:10]:
>>>> +
>>>> +u32 omap_control_status_read(void)
>>>> +{
>>>> +	return __raw_readl(omap_control_base);
>>>> +}
>>> Ah OK it's changed here.. Sorry I was looking at the older
>>> version.
>>>
>>>> +void __init of_omap_control_init(const struct of_device_id *matches)
>>>> +{
>>>> +	struct device_node *np;
>>>> +	struct property *pp = 0;
>>>> +
>>>> +	for_each_matching_node(np, matches) {
>>>> +		pp = of_find_property(np, "reg", NULL);
>>>> +		if(pp) {
>>>> +			omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
>>>> +			omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
>>>> +			/*
>>>> +			 * Map control module register CONTROL_STATUS register:
>>>> +			 * omap24xx - OMAP24XX_CONTROL_STATUS
>>>> +			 * am33xx   - AM33XX_CONTROL_STATUS
>>>> +			 * omap34xx - OMAP343X_CONTROL_STATUS
>>>> +			 * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
>>>> +			 * omap54xx - OMAP5XXX_CONTROL_STATUS
>>>> +			 */
>>>> +			omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
>>>> +		}
>>>> +	}
>>>> +}
>>> You should probably add a function for setting omap_control_base
>>> separately from *set_globals* in arch/arm/mach-omap2/common.c.
>>> That way it's initialized early for id.c, and you can initialize
>>> everything else later as regular device drivers.
>>>
>>> FYI, we want to initialize as much as possible late so we have
>>> proper debugging console set up in case things go wrong.
>> Hmm it seems that omap_control_base is now only initialized for DT boot
>> case? This will break booting on almost all systems..
> Looking at things more, looks like omap_type() is getting called
> early from timer.c. So maybe just let set_globals initialize
> omap_control_base and let omap_type() read that directly. That way
> the SCM core driver can behave like a regular device driver and it
> does not need to be initialized early.

  Yes, omap_type() is called very early , that is why I'm using early_initcall for omap_control_base initialization.

Do you mean following?:
void __init omap2_set_globals_control(struct omap_globals *omap2_globals)
{
    if (omap2_globals->ctrl)
        omap2_ctrl_base = omap2_globals->ctrl;

    if (omap2_globals->ctrl_pad)
        omap4_ctrl_pad_base = omap2_globals->ctrl_pad;

    omap_control_base = omap2_ctrl_base;  // this line is added
}

  Or you suggest to move
void __init of_omap_control_init(const struct of_device_id *matches)
{
    struct device_node *np;
    struct property *pp = 0;

    for_each_matching_node(np, matches) {
        pp = of_find_property(np, "reg", NULL);
        if(pp) {
            omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
            omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
            /*
             * Map control module register CONTROL_STATUS register:
             * omap24xx - OMAP24XX_CONTROL_STATUS
             * am33xx   - AM33XX_CONTROL_STATUS
             * omap34xx - OMAP343X_CONTROL_STATUS
             * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
             * omap54xx - OMAP5XXX_CONTROL_STATUS
             */
            omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
        }
    }
}

into omap2_set_globals_control() ?

Also if we move omap_control_base initialization to omap2_set_globals_control(), than the initialization routine of drivers/mfd/omap-control-core.c become empty, because omap_control_base is the only thing that is initialized in omap-control-core driver.

  BR,
    Konstantin Baydarov.

>
> Regards,
>
> Tony
> --
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AnilKumar, Chimata Aug. 29, 2012, 12:33 p.m. UTC | #6

Hi Konstantin,

On Wed, Jul 25, 2012 at 16:35:16, Konstantin Baydarov wrote:
> This patch introduces a MFD core device driver for
> OMAP system control module.
> 
> The control module allows software control of
> various static modes supported by the device. It is
> composed of two control submodules: general control
> module and device (padconfiguration) control
> module.
> 
> Device driver is probed with postcore_initcall.
> Control module register CONTROL_STATUS that is needed
> by omap_type() is early mapped by postcore_initcall_sync.
> 
> Signed-off-by: J Keerthy <[e-mail]>
> Signed-off-by: Kishon Vijay Abraham I <[e-mail]>
> Signed-off-by: Eduardo Valentin <[e-mail]>
> Signed-off-by: Konstantin Baydarov <[e-mail]>
> ---
>  .../devicetree/bindings/mfd/omap_control.txt       |   32 ++++
>  arch/arm/mach-omap2/Kconfig                        |    1 +
>  arch/arm/plat-omap/Kconfig                         |    4 +
>  drivers/mfd/Kconfig                                |    6 +
>  drivers/mfd/Makefile                               |    1 +
>  drivers/mfd/omap-control-core.c                    |  162 ++++++++++++++++++++
>  include/linux/mfd/omap_control.h                   |   35 +++++
>  7 files changed, 241 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mfd/omap_control.txt
>  create mode 100644 drivers/mfd/omap-control-core.c
>  create mode 100644 include/linux/mfd/omap_control.h
> 
> diff --git a/Documentation/devicetree/bindings/mfd/omap_control.txt b/Documentation/devicetree/bindings/mfd/omap_control.txt
> new file mode 100644
> index 0000000..a9dca9e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/omap_control.txt
> @@ -0,0 +1,32 @@
> +* Texas Instrument OMAP System Control Module (SCM) bindings
> +
> +The control module allows software control of various static modes supported by
> +the device. The control module controls the settings of various device  modules
> +through register configuration and internal signals. It also controls  the  pad
> +configuration, pin functional multiplexing, and the routing of internal signals
> +(such as PRCM  signals or DMA requests)  to output pins configured for hardware
> +observability.
> +
> +Required properties:
> +- compatible : Should be:
> +  - "ti,omap3-control" for OMAP3 support
> +  - "ti,omap4-control" for OMAP4 support
> +  - "ti,omap5-control" for OMAP5 support
> +
> +OMAP specific properties:
> +- ti,hwmods: Name of the hwmod associated to the control module:
> +  Should be "ctrl_module_core";
> +
> +OMAP CONTROL_STATUS register:
> +reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */
> +
> +Examples:
> +ctrl_module_core: ctrl_module_core@4A0022C4 {
> +	compatible = "ti,omap4-control";
> +	#address-cells = <1>;
> +	#size-cells = <1>;
> +	/* ranges; */
> +	ti,hwmods = "ctrl_module_core";
> +	reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */
> +};
> +
> diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
> index dd0fbf7..1235576 100644
> --- a/arch/arm/mach-omap2/Kconfig
> +++ b/arch/arm/mach-omap2/Kconfig
> @@ -59,6 +59,7 @@ config ARCH_OMAP4
>  	select ARM_ERRATA_720789
>  	select ARCH_HAS_OPP
>  	select PM_RUNTIME if CPU_IDLE
> +	select ARCH_HAS_CONTROL_MODULE
>  	select PM_OPP if PM
>  	select USB_ARCH_HAS_EHCI if USB_SUPPORT
>  	select ARM_CPU_SUSPEND if PM
> diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
> index dd36eba..2b2c9d8 100644
> --- a/arch/arm/plat-omap/Kconfig
> +++ b/arch/arm/plat-omap/Kconfig
> @@ -5,6 +5,10 @@ menu "TI OMAP Common Features"
>  config ARCH_OMAP_OTG
>  	bool
>  
> +config ARCH_HAS_CONTROL_MODULE
> +	bool
> +	select MFD_OMAP_CONTROL
> +
>  choice
>  	prompt "OMAP System Type"
>  	default ARCH_OMAP2PLUS
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 92144ed..530ac60 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -823,6 +823,12 @@ config MFD_WL1273_CORE
>  	  driver connects the radio-wl1273 V4L2 module and the wl1273
>  	  audio codec.
>  
> +config MFD_OMAP_CONTROL
> +	bool "Texas Instruments OMAP System control module"
> +	depends on ARCH_HAS_CONTROL_MODULE
> +	help
> +	  This is the core driver for system control module.
> +
>  config MFD_OMAP_USB_HOST
>  	bool "Support OMAP USBHS core driver"
>  	depends on USB_EHCI_HCD_OMAP || USB_OHCI_HCD_OMAP3
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 75f6ed6..b037443 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -107,6 +107,7 @@ obj-$(CONFIG_MFD_TPS6586X)	+= tps6586x.o
>  obj-$(CONFIG_MFD_VX855)		+= vx855.o
>  obj-$(CONFIG_MFD_WL1273_CORE)	+= wl1273-core.o
>  obj-$(CONFIG_MFD_CS5535)	+= cs5535-mfd.o
> +obj-$(CONFIG_MFD_OMAP_CONTROL)	+= omap-control-core.o
>  obj-$(CONFIG_MFD_OMAP_USB_HOST)	+= omap-usb-host.o
>  obj-$(CONFIG_MFD_PM8921_CORE) 	+= pm8921-core.o
>  obj-$(CONFIG_MFD_PM8XXX_IRQ) 	+= pm8xxx-irq.o
> diff --git a/drivers/mfd/omap-control-core.c b/drivers/mfd/omap-control-core.c
> new file mode 100644
> index 0000000..cefbc5a
> --- /dev/null
> +++ b/drivers/mfd/omap-control-core.c
> @@ -0,0 +1,162 @@
> +/*
> + * OMAP system control module driver file
> + *
> + * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
> + * Contacts:
> + * Based on original code written by:
> + *    J Keerthy <[e-mail]>
> + *    Moiz Sonasath <[e-mail]>
> + * MFD clean up and re-factoring:
> + *    Eduardo Valentin <[e-mail]>
> + *    Konstantin Baydarov <[e-mail]>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * 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/module.h>
> +#include <linux/export.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/io.h>
> +#include <linux/err.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_address.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/omap_control.h>
> +
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +
> +void __iomem *omap_control_base;
> +unsigned long omap_control_phys_base;
> +size_t omap_control_mapsize;
> +
> +u32 omap_control_status_read(void)
> +{
> +	return __raw_readl(omap_control_base);
> +}

In AM335X, D_CAN IP uses single CONTROL module register to
initialize D_CAN ram (D_CAN_RAMINIT). In order to enable
D_CAN RAM we have to write to that register in sync with
clock enable/disable.

How can I use this driver to handle this usecase? Similar to
above API?

Currently this is handled using platform call back (example below)

In arch/arm/mach-omap2/devices.c:
static void d_can_hw_raminit(unsigned int instance, unsigned int enable)
{
        u32 val;

        /* Read the value */
        val = readl(AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
        if (enable) {
                /* Set to "1" */
                val &= ~AM33XX_DCAN_RAMINIT_START(instance);
                val |= AM33XX_DCAN_RAMINIT_START(instance);
                writel(val, AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
        } else {
                /* Set to "0" */
                val &= ~AM33XX_DCAN_RAMINIT_START(instance);
                writel(val, AM33XX_CTRL_REGADDR(AM33XX_DCAN_RAMINIT_OFFSET));
        }
}

In drivers/net/can/c_can/c_can.c:
void d_can_reset_ram(struct d_can_priv *d_can, unsigned int instance,
                                        unsigned int enable)
{
        if (d_can->ram_init)
                d_can->ram_init(instance, enable);
}

Thanks
AnilKumar

Patch

diff --git a/Documentation/devicetree/bindings/mfd/omap_control.txt b/Documentation/devicetree/bindings/mfd/omap_control.txt
new file mode 100644
index 0000000..a9dca9e
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/omap_control.txt
@@ -0,0 +1,32 @@ 
+* Texas Instrument OMAP System Control Module (SCM) bindings
+
+The control module allows software control of various static modes supported by
+the device. The control module controls the settings of various device  modules
+through register configuration and internal signals. It also controls  the  pad
+configuration, pin functional multiplexing, and the routing of internal signals
+(such as PRCM  signals or DMA requests)  to output pins configured for hardware
+observability.
+
+Required properties:
+- compatible : Should be:
+  - "ti,omap3-control" for OMAP3 support
+  - "ti,omap4-control" for OMAP4 support
+  - "ti,omap5-control" for OMAP5 support
+
+OMAP specific properties:
+- ti,hwmods: Name of the hwmod associated to the control module:
+  Should be "ctrl_module_core";
+
+OMAP CONTROL_STATUS register:
+reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */
+
+Examples:
+ctrl_module_core: ctrl_module_core@4A0022C4 {
+	compatible = "ti,omap4-control";
+	#address-cells = <1>;
+	#size-cells = <1>;
+	/* ranges; */
+	ti,hwmods = "ctrl_module_core";
+	reg = <0x4A0022C4 0x4>; /* CONTROL_STATUS register */
+};
+
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index dd0fbf7..1235576 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -59,6 +59,7 @@  config ARCH_OMAP4
 	select ARM_ERRATA_720789
 	select ARCH_HAS_OPP
 	select PM_RUNTIME if CPU_IDLE
+	select ARCH_HAS_CONTROL_MODULE
 	select PM_OPP if PM
 	select USB_ARCH_HAS_EHCI if USB_SUPPORT
 	select ARM_CPU_SUSPEND if PM
diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
index dd36eba..2b2c9d8 100644
--- a/arch/arm/plat-omap/Kconfig
+++ b/arch/arm/plat-omap/Kconfig
@@ -5,6 +5,10 @@  menu "TI OMAP Common Features"
 config ARCH_OMAP_OTG
 	bool
 
+config ARCH_HAS_CONTROL_MODULE
+	bool
+	select MFD_OMAP_CONTROL
+
 choice
 	prompt "OMAP System Type"
 	default ARCH_OMAP2PLUS
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 92144ed..530ac60 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -823,6 +823,12 @@  config MFD_WL1273_CORE
 	  driver connects the radio-wl1273 V4L2 module and the wl1273
 	  audio codec.
 
+config MFD_OMAP_CONTROL
+	bool "Texas Instruments OMAP System control module"
+	depends on ARCH_HAS_CONTROL_MODULE
+	help
+	  This is the core driver for system control module.
+
 config MFD_OMAP_USB_HOST
 	bool "Support OMAP USBHS core driver"
 	depends on USB_EHCI_HCD_OMAP || USB_OHCI_HCD_OMAP3
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 75f6ed6..b037443 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -107,6 +107,7 @@  obj-$(CONFIG_MFD_TPS6586X)	+= tps6586x.o
 obj-$(CONFIG_MFD_VX855)		+= vx855.o
 obj-$(CONFIG_MFD_WL1273_CORE)	+= wl1273-core.o
 obj-$(CONFIG_MFD_CS5535)	+= cs5535-mfd.o
+obj-$(CONFIG_MFD_OMAP_CONTROL)	+= omap-control-core.o
 obj-$(CONFIG_MFD_OMAP_USB_HOST)	+= omap-usb-host.o
 obj-$(CONFIG_MFD_PM8921_CORE) 	+= pm8921-core.o
 obj-$(CONFIG_MFD_PM8XXX_IRQ) 	+= pm8xxx-irq.o
diff --git a/drivers/mfd/omap-control-core.c b/drivers/mfd/omap-control-core.c
new file mode 100644
index 0000000..cefbc5a
--- /dev/null
+++ b/drivers/mfd/omap-control-core.c
@@ -0,0 +1,162 @@ 
+/*
+ * OMAP system control module driver file
+ *
+ * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
+ * Contacts:
+ * Based on original code written by:
+ *    J Keerthy <[e-mail]>
+ *    Moiz Sonasath <[e-mail]>
+ * MFD clean up and re-factoring:
+ *    Eduardo Valentin <[e-mail]>
+ *    Konstantin Baydarov <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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/module.h>
+#include <linux/export.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/omap_control.h>
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+void __iomem *omap_control_base;
+unsigned long omap_control_phys_base;
+size_t omap_control_mapsize;
+
+u32 omap_control_status_read(void)
+{
+	return __raw_readl(omap_control_base);
+}
+
+static const struct of_device_id of_omap_control_match[] = {
+	{ .compatible = "ti,omap3-control", },
+	{ .compatible = "ti,omap4-control", },
+	{ .compatible = "ti,omap5-control", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, of_omap_control_match);
+
+/*
+ *  Request control module resources
+ */
+static int __devinit omap_control_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct device *dev = &pdev->dev;
+	const char *name;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENOMEM;
+
+	if (!res) {
+		dev_err(dev, "invalid resource\n");
+		return -EINVAL;
+	}
+
+	name = res->name ?: dev_name(dev);
+
+	/*
+	 * Can't use res->start and resource_size(res) from platform_get_resource,
+	 * because omap_device_alloc() overwrites DT resources -
+	 * using omap_control_phys_base, omap_control_mapsize instead
+	 */
+	if (!devm_request_mem_region(dev, omap_control_phys_base, omap_control_mapsize, name)) {
+		dev_err(dev, "can't request region for resource %pR\n", res);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+
+static struct platform_driver omap_control_driver = {
+	.probe			= omap_control_probe,
+	.driver = {
+		.name		= "omap-control-core",
+		.owner		= THIS_MODULE,
+		.of_match_table	= of_omap_control_match,
+	},
+};
+
+int __init omap_control_of_init(struct device_node *node,
+			     struct device_node *parent)
+{
+	struct resource res;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	if (of_address_to_resource(node, 0, &res)) {
+		WARN(1, "unable to get intc registers\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void __init of_omap_control_init(const struct of_device_id *matches)
+{
+	struct device_node *np;
+	struct property *pp = 0;
+
+	for_each_matching_node(np, matches) {
+		pp = of_find_property(np, "reg", NULL);
+		if(pp) {
+			omap_control_phys_base = (unsigned long)be32_to_cpup(pp->value);
+			omap_control_mapsize = (size_t)be32_to_cpup( (void*)((char*)pp->value + 4) );
+			/*
+			 * Map control module register CONTROL_STATUS register:
+			 * omap24xx - OMAP24XX_CONTROL_STATUS
+			 * am33xx   - AM33XX_CONTROL_STATUS
+			 * omap34xx - OMAP343X_CONTROL_STATUS
+			 * omap44xx - OMAP4_CTRL_MODULE_CORE_STATUS
+			 * omap54xx - OMAP5XXX_CONTROL_STATUS
+			 */
+			omap_control_base = ioremap(omap_control_phys_base, omap_control_mapsize);
+		}
+	}
+}
+
+static int __init
+omap_control_early_initcall(void)
+{
+	of_omap_control_init(of_omap_control_match);
+
+	return 0;
+}
+early_initcall(omap_control_early_initcall);
+
+static int __init omap_control_init(void)
+{
+	return platform_driver_register(&omap_control_driver);
+}
+postcore_initcall_sync(omap_control_init);
+
+static void __exit omap_control_exit(void)
+{
+	platform_driver_unregister(&omap_control_driver);
+}
+module_exit(omap_control_exit);
+early_platform_init("early_omap_control", &omap_control_driver);
+
+MODULE_DESCRIPTION("OMAP system control module driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:omap-control-core");
+MODULE_AUTHOR("Texas Instruments Inc.");
diff --git a/include/linux/mfd/omap_control.h b/include/linux/mfd/omap_control.h
new file mode 100644
index 0000000..ee90a38
--- /dev/null
+++ b/include/linux/mfd/omap_control.h
@@ -0,0 +1,35 @@ 
+/*
+ * OMAP system control module header file
+ *
+ * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
+ * Contact:
+ *   J Keerthy <[e-mail]>
+ *   Moiz Sonasath <[e-mail]>
+ *   Abraham, Kishon Vijay <[e-mail]>
+ *   Eduardo Valentin <[e-mail]>
+ *   Konstantin Baydarov <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ */
+
+#ifndef __DRIVERS_OMAP_CONTROL_H
+#define __DRIVERS_OMAP_CONTROL_H
+
+#ifdef CONFIG_MFD_OMAP_CONTROL
+u32 omap_control_status_read(void);
+#else
+static inline u32 omap_control_status_read(void)
+{
+	return 0;
+}
+#endif
+
+#endif /* __DRIVERS_OMAP_CONTROL_H */