Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1275480 > unrolled thread

[PATCH v4 2/5] mfd: syscon: add a DT property to set value width

Started byDamien Riegel <damien.riegel@savoirfairelinux.com>
First post2015-11-23 16:30 +0100
Last post2015-11-24 18:30 +0100
Articles 5 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  [PATCH v4 2/5] mfd: syscon: add a DT property to set value width Damien Riegel <damien.riegel@savoirfairelinux.com> - 2015-11-23 16:30 +0100
    Re: [PATCH v4 2/5] mfd: syscon: add a DT property to set value width Lee Jones <lee.jones@linaro.org> - 2015-11-24 09:30 +0100
      Re: [PATCH v4 2/5] mfd: syscon: add a DT property to set value width Damien Riegel <damien.riegel@savoirfairelinux.com> - 2015-11-24 17:40 +0100
        Re: [PATCH v4 2/5] mfd: syscon: add a DT property to set value width Lee Jones <lee.jones@linaro.org> - 2015-11-24 18:30 +0100
          Re: [PATCH v4 2/5] mfd: syscon: add a DT property to set value width Lee Jones <lee.jones@linaro.org> - 2015-11-24 18:30 +0100

#1275480 — [PATCH v4 2/5] mfd: syscon: add a DT property to set value width

FromDamien Riegel <damien.riegel@savoirfairelinux.com>
Date2015-11-23 16:30 +0100
Subject[PATCH v4 2/5] mfd: syscon: add a DT property to set value width
Message-ID<qy1e2-3DU-5@gated-at.bofh.it>
Currently syscon has a fixed configuration of 32 bits for register and
values widths. In some cases, it would be desirable to be able to
customize the value width.

For example, certain boards (like the ones manufactured by Technologic
Systems) have a FPGA that is memory-mapped, but its registers are only
16-bit wide.

This patch adds an optional "bus-width" DT binding for syscon that
allows to change the width for the data bus (i.e. val_bits). If this
property is provided, it will also adjust the register stride to
bus-width / 8. If not provided, the default configuration is used.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
---
 Documentation/devicetree/bindings/mfd/syscon.txt |  3 +++
 drivers/mfd/syscon.c                             | 13 +++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt
index fe8150b..4c9d187 100644
--- a/Documentation/devicetree/bindings/mfd/syscon.txt
+++ b/Documentation/devicetree/bindings/mfd/syscon.txt
@@ -13,6 +13,9 @@ Required properties:
 - compatible: Should contain "syscon".
 - reg: the register region can be accessed from syscon
 
+Optional property:
+- bus-width: width of the data bus. Can be <8>, <16>, <32>, or <64>.
+
 Examples:
 gpr: iomuxc-gpr@020e0000 {
 	compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 176bf0f..5a93d80 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -47,6 +47,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
 	struct syscon *syscon;
 	struct regmap *regmap;
 	void __iomem *base;
+	u32 bus_width;
 	int ret;
 	struct regmap_config syscon_config = syscon_regmap_config;
 
@@ -69,6 +70,18 @@ static struct syscon *of_syscon_register(struct device_node *np)
 	 else if (of_property_read_bool(np, "little-endian"))
 		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
 
+	/*
+	 * search for bus-width property in DT. If it is not provided, default
+	 * to 32-bit. regmap_init_mmio will return an error if syscon_config's
+	 * values are invalid so there is no need to check them here.
+	 */
+	ret = of_property_read_u32(np, "bus-width", &bus_width);
+	if (ret)
+		bus_width = 32;
+
+	syscon_config.val_bits = bus_width;
+	syscon_config.reg_stride = syscon_config.val_bits / 8;
+
 	regmap = regmap_init_mmio(NULL, base, &syscon_config);
 	if (IS_ERR(regmap)) {
 		pr_err("regmap init failed\n");
-- 
2.5.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]

#1276152

FromLee Jones <lee.jones@linaro.org>
Date2015-11-24 09:30 +0100
Message-ID<qyh97-5D3-5@gated-at.bofh.it>
In reply to#1275480
On Mon, 23 Nov 2015, Damien Riegel wrote:

> Currently syscon has a fixed configuration of 32 bits for register and
> values widths. In some cases, it would be desirable to be able to
> customize the value width.
> 
> For example, certain boards (like the ones manufactured by Technologic
> Systems) have a FPGA that is memory-mapped, but its registers are only
> 16-bit wide.
> 
> This patch adds an optional "bus-width" DT binding for syscon that
> allows to change the width for the data bus (i.e. val_bits). If this
> property is provided, it will also adjust the register stride to
> bus-width / 8. If not provided, the default configuration is used.
> 
> Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
> ---
>  Documentation/devicetree/bindings/mfd/syscon.txt |  3 +++
>  drivers/mfd/syscon.c                             | 13 +++++++++++++
>  2 files changed, 16 insertions(+)

Works for me.

For my own reference:
  Acked-by: Lee Jones <lee.jones@linaro.org>

How would you like this set to be handled?

> diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt
> index fe8150b..4c9d187 100644
> --- a/Documentation/devicetree/bindings/mfd/syscon.txt
> +++ b/Documentation/devicetree/bindings/mfd/syscon.txt
> @@ -13,6 +13,9 @@ Required properties:
>  - compatible: Should contain "syscon".
>  - reg: the register region can be accessed from syscon
>  
> +Optional property:
> +- bus-width: width of the data bus. Can be <8>, <16>, <32>, or <64>.
> +
>  Examples:
>  gpr: iomuxc-gpr@020e0000 {
>  	compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
> index 176bf0f..5a93d80 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -47,6 +47,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
>  	struct syscon *syscon;
>  	struct regmap *regmap;
>  	void __iomem *base;
> +	u32 bus_width;
>  	int ret;
>  	struct regmap_config syscon_config = syscon_regmap_config;
>  
> @@ -69,6 +70,18 @@ static struct syscon *of_syscon_register(struct device_node *np)
>  	 else if (of_property_read_bool(np, "little-endian"))
>  		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
>  
> +	/*
> +	 * search for bus-width property in DT. If it is not provided, default
> +	 * to 32-bit. regmap_init_mmio will return an error if syscon_config's
> +	 * values are invalid so there is no need to check them here.
> +	 */
> +	ret = of_property_read_u32(np, "bus-width", &bus_width);
> +	if (ret)
> +		bus_width = 32;
> +
> +	syscon_config.val_bits = bus_width;
> +	syscon_config.reg_stride = syscon_config.val_bits / 8;
> +
>  	regmap = regmap_init_mmio(NULL, base, &syscon_config);
>  	if (IS_ERR(regmap)) {
>  		pr_err("regmap init failed\n");

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1276635

FromDamien Riegel <damien.riegel@savoirfairelinux.com>
Date2015-11-24 17:40 +0100
Message-ID<qyoNk-29z-27@gated-at.bofh.it>
In reply to#1276152
On Tue, Nov 24, 2015 at 08:20:36AM +0000, Lee Jones wrote:
> On Mon, 23 Nov 2015, Damien Riegel wrote:
> 
> > Currently syscon has a fixed configuration of 32 bits for register and
> > values widths. In some cases, it would be desirable to be able to
> > customize the value width.
> > 
> > For example, certain boards (like the ones manufactured by Technologic
> > Systems) have a FPGA that is memory-mapped, but its registers are only
> > 16-bit wide.
> > 
> > This patch adds an optional "bus-width" DT binding for syscon that
> > allows to change the width for the data bus (i.e. val_bits). If this
> > property is provided, it will also adjust the register stride to
> > bus-width / 8. If not provided, the default configuration is used.
> > 
> > Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
> > ---
> >  Documentation/devicetree/bindings/mfd/syscon.txt |  3 +++
> >  drivers/mfd/syscon.c                             | 13 +++++++++++++
> >  2 files changed, 16 insertions(+)
> 
> Works for me.
> 
> For my own reference:
>   Acked-by: Lee Jones <lee.jones@linaro.org>

This pachset requires a new version to fix something in the watchdog,
I will add your Ack in the v5.

> 
> How would you like this set to be handled?
> 

Not sure what you mean. Actually, I don't know how it works for such
patchset with changes across multiple subsystems. What are the options?


Damien
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1276671

FromLee Jones <lee.jones@linaro.org>
Date2015-11-24 18:30 +0100
Message-ID<qypzH-2HH-1@gated-at.bofh.it>
In reply to#1276635
On Tue, 24 Nov 2015, Damien Riegel wrote:

> On Tue, Nov 24, 2015 at 08:20:36AM +0000, Lee Jones wrote:
> > On Mon, 23 Nov 2015, Damien Riegel wrote:
> > 
> > > Currently syscon has a fixed configuration of 32 bits for register and
> > > values widths. In some cases, it would be desirable to be able to
> > > customize the value width.
> > > 
> > > For example, certain boards (like the ones manufactured by Technologic
> > > Systems) have a FPGA that is memory-mapped, but its registers are only
> > > 16-bit wide.
> > > 
> > > This patch adds an optional "bus-width" DT binding for syscon that
> > > allows to change the width for the data bus (i.e. val_bits). If this
> > > property is provided, it will also adjust the register stride to
> > > bus-width / 8. If not provided, the default configuration is used.
> > > 
> > > Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
> > > ---
> > >  Documentation/devicetree/bindings/mfd/syscon.txt |  3 +++
> > >  drivers/mfd/syscon.c                             | 13 +++++++++++++
> > >  2 files changed, 16 insertions(+)
> > 
> > Works for me.
> > 
> > For my own reference:
> >   Acked-by: Lee Jones <lee.jones@linaro.org>
> 
> This pachset requires a new version to fix something in the watchdog,
> I will add your Ack in the v5.
> 
> > 
> > How would you like this set to be handled?
> > 
> 
> Not sure what you mean. Actually, I don't know how it works for such
> patchset with changes across multiple subsystems. What are the options?

I'm happy to handle it, I just need Acks from the other Maintainers.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [next] | [standalone]

#1276672

FromLee Jones <lee.jones@linaro.org>
Date2015-11-24 18:30 +0100
Message-ID<qypzI-2HH-11@gated-at.bofh.it>
In reply to#1276671
On Tue, 24 Nov 2015, Lee Jones wrote:

> On Tue, 24 Nov 2015, Damien Riegel wrote:
> 
> > On Tue, Nov 24, 2015 at 08:20:36AM +0000, Lee Jones wrote:
> > > On Mon, 23 Nov 2015, Damien Riegel wrote:
> > > 
> > > > Currently syscon has a fixed configuration of 32 bits for register and
> > > > values widths. In some cases, it would be desirable to be able to
> > > > customize the value width.
> > > > 
> > > > For example, certain boards (like the ones manufactured by Technologic
> > > > Systems) have a FPGA that is memory-mapped, but its registers are only
> > > > 16-bit wide.
> > > > 
> > > > This patch adds an optional "bus-width" DT binding for syscon that
> > > > allows to change the width for the data bus (i.e. val_bits). If this
> > > > property is provided, it will also adjust the register stride to
> > > > bus-width / 8. If not provided, the default configuration is used.
> > > > 
> > > > Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
> > > > ---
> > > >  Documentation/devicetree/bindings/mfd/syscon.txt |  3 +++
> > > >  drivers/mfd/syscon.c                             | 13 +++++++++++++
> > > >  2 files changed, 16 insertions(+)
> > > 
> > > Works for me.
> > > 
> > > For my own reference:
> > >   Acked-by: Lee Jones <lee.jones@linaro.org>
> > 
> > This pachset requires a new version to fix something in the watchdog,
> > I will add your Ack in the v5.
> > 
> > > 
> > > How would you like this set to be handled?
> > > 
> > 
> > Not sure what you mean. Actually, I don't know how it works for such
> > patchset with changes across multiple subsystems. What are the options?
> 
> I'm happy to handle it, I just need Acks from the other Maintainers.

Actually, I just need Wim's Ack.

The 2 ARM patches will go in separately.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web