From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Tue, 8 Dec 2015 13:50:40 +0000 Subject: [PATCH v7 2/6] mfd: syscon: add a DT property to set value width In-Reply-To: <20151207194218.GB6030@localhost> References: <1448899191-13891-1-git-send-email-damien.riegel@savoirfairelinux.com> <1448899191-13891-3-git-send-email-damien.riegel@savoirfairelinux.com> <20151207094020.GF3384@x1> <20151207194218.GB6030@localhost> Message-ID: <20151208135040.GH3384@x1> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, 07 Dec 2015, Damien Riegel wrote: > On Mon, Dec 07, 2015 at 09:40:20AM +0000, Lee Jones wrote: > > On Mon, 30 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 "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 > > > --- > > > Documentation/devicetree/bindings/mfd/syscon.txt | 4 ++++ > > > drivers/mfd/syscon.c | 13 +++++++++++++ > > > 2 files changed, 17 insertions(+) > > > > Applied, thanks. > > > Hi Lee, > > Good to see this patch applied. What's going on now with the other > patches of this serie ? How should I handle them ? Are there any build dependencies between them? > > > 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"); > > -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org ? Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog