From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754510AbbK3TAX (ORCPT ); Mon, 30 Nov 2015 14:00:23 -0500 Received: from mail.kernel.org ([198.145.29.136]:51330 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754143AbbK3TAV (ORCPT ); Mon, 30 Nov 2015 14:00:21 -0500 Date: Mon, 30 Nov 2015 13:00:15 -0600 From: Rob Herring To: Damien Riegel Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, Lee Jones , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Russell King , Shawn Guo , Sascha Hauer , Arnd Bergmann , Samuel Ortiz , Wim Van Sebroeck , Guenter Roeck , kernel@savoirfairelinux.com Subject: Re: [PATCH v7 2/6] mfd: syscon: add a DT property to set value width Message-ID: <20151130190015.GA31006@rob-hp-laptop> References: <1448899191-13891-1-git-send-email-damien.riegel@savoirfairelinux.com> <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 30, 2015 at 10:59:47AM -0500, 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 "reg-io-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 set the register stride to > reg-io-width's value. If not provided, the default configuration is > used. > > Signed-off-by: Damien Riegel Acked-by: Rob Herring > --- > Documentation/devicetree/bindings/mfd/syscon.txt | 4 ++++ > drivers/mfd/syscon.c | 13 +++++++++++++ > 2 files changed, 17 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt > index fe8150b..408f768 100644 > --- a/Documentation/devicetree/bindings/mfd/syscon.txt > +++ b/Documentation/devicetree/bindings/mfd/syscon.txt > @@ -13,6 +13,10 @@ Required properties: > - compatible: Should contain "syscon". > - reg: the register region can be accessed from syscon > > +Optional property: > +- reg-io-width: the size (in bytes) of the IO accesses that should be > + performed on the device. > + > 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..b7aabee 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 reg_io_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 reg-io-width property in DT. If it is not provided, > + * default to 4 bytes. regmap_init_mmio will return an error if values > + * are invalid so there is no need to check them here. > + */ > + ret = of_property_read_u32(np, "reg-io-width", ®_io_width); > + if (ret) > + reg_io_width = 4; > + > + syscon_config.reg_stride = reg_io_width; > + syscon_config.val_bits = reg_io_width * 8; > + > regmap = regmap_init_mmio(NULL, base, &syscon_config); > if (IS_ERR(regmap)) { > pr_err("regmap init failed\n"); > -- > 2.5.0 > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH v7 2/6] mfd: syscon: add a DT property to set value width Date: Mon, 30 Nov 2015 13:00:15 -0600 Message-ID: <20151130190015.GA31006@rob-hp-laptop> References: <1448899191-13891-1-git-send-email-damien.riegel@savoirfairelinux.com> <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1448899191-13891-3-git-send-email-damien.riegel-4ysUXcep3aM1wj+D4I0NRVaTQe2KTcn/@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Damien Riegel Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-watchdog-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Lee Jones , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Russell King , Shawn Guo , Sascha Hauer , Arnd Bergmann , Samuel Ortiz , Wim Van Sebroeck , Guenter Roeck , kernel-4ysUXcep3aM1wj+D4I0NRVaTQe2KTcn/@public.gmane.org List-Id: devicetree@vger.kernel.org On Mon, Nov 30, 2015 at 10:59:47AM -0500, 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 "reg-io-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 set the register stride to > reg-io-width's value. If not provided, the default configuration is > used. > > Signed-off-by: Damien Riegel Acked-by: Rob Herring > --- > Documentation/devicetree/bindings/mfd/syscon.txt | 4 ++++ > drivers/mfd/syscon.c | 13 +++++++++++++ > 2 files changed, 17 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt > index fe8150b..408f768 100644 > --- a/Documentation/devicetree/bindings/mfd/syscon.txt > +++ b/Documentation/devicetree/bindings/mfd/syscon.txt > @@ -13,6 +13,10 @@ Required properties: > - compatible: Should contain "syscon". > - reg: the register region can be accessed from syscon > > +Optional property: > +- reg-io-width: the size (in bytes) of the IO accesses that should be > + performed on the device. > + > 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..b7aabee 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 reg_io_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 reg-io-width property in DT. If it is not provided, > + * default to 4 bytes. regmap_init_mmio will return an error if values > + * are invalid so there is no need to check them here. > + */ > + ret = of_property_read_u32(np, "reg-io-width", ®_io_width); > + if (ret) > + reg_io_width = 4; > + > + syscon_config.reg_stride = reg_io_width; > + syscon_config.val_bits = reg_io_width * 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 devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: robh@kernel.org (Rob Herring) Date: Mon, 30 Nov 2015 13:00:15 -0600 Subject: [PATCH v7 2/6] mfd: syscon: add a DT property to set value width In-Reply-To: <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> References: <1448899191-13891-1-git-send-email-damien.riegel@savoirfairelinux.com> <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> Message-ID: <20151130190015.GA31006@rob-hp-laptop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Nov 30, 2015 at 10:59:47AM -0500, 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 "reg-io-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 set the register stride to > reg-io-width's value. If not provided, the default configuration is > used. > > Signed-off-by: Damien Riegel Acked-by: Rob Herring > --- > Documentation/devicetree/bindings/mfd/syscon.txt | 4 ++++ > drivers/mfd/syscon.c | 13 +++++++++++++ > 2 files changed, 17 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt > index fe8150b..408f768 100644 > --- a/Documentation/devicetree/bindings/mfd/syscon.txt > +++ b/Documentation/devicetree/bindings/mfd/syscon.txt > @@ -13,6 +13,10 @@ Required properties: > - compatible: Should contain "syscon". > - reg: the register region can be accessed from syscon > > +Optional property: > +- reg-io-width: the size (in bytes) of the IO accesses that should be > + performed on the device. > + > Examples: > gpr: iomuxc-gpr at 020e0000 { > compatible = "fsl,imx6q-iomuxc-gpr", "syscon"; > diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c > index 176bf0f..b7aabee 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 reg_io_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 reg-io-width property in DT. If it is not provided, > + * default to 4 bytes. regmap_init_mmio will return an error if values > + * are invalid so there is no need to check them here. > + */ > + ret = of_property_read_u32(np, "reg-io-width", ®_io_width); > + if (ret) > + reg_io_width = 4; > + > + syscon_config.reg_stride = reg_io_width; > + syscon_config.val_bits = reg_io_width * 8; > + > regmap = regmap_init_mmio(NULL, base, &syscon_config); > if (IS_ERR(regmap)) { > pr_err("regmap init failed\n"); > -- > 2.5.0 >