diff options
author | Adrian Alonso <aalonso@freescale.com> | 2015-09-30 16:11:09 (GMT) |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2015-10-02 21:45:17 (GMT) |
commit | a169400b506e98bb90a92c7211f4bed751341750 (patch) | |
tree | 97b2aa56559aaf7eec19d8af1a3e406f8061d425 /Documentation/devicetree/bindings | |
parent | 978fd1d7265aee0d8be501f416017d029e6977a7 (diff) | |
download | linux-a169400b506e98bb90a92c7211f4bed751341750.tar.xz |
pinctrl: freescale: imx: imx7d iomuxc-lpsr devicetree bindings
Add iomuxc-lpsr devicetree bindings documentation
Provide documentation context as well an example on
pheriperals that could use pad from either iomuxc controller
supported by iMX7D SoC
Signed-off-by: Adrian Alonso <aalonso@freescale.com>
Acked-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/devicetree/bindings')
-rw-r--r-- | Documentation/devicetree/bindings/pinctrl/fsl,imx7d-pinctrl.txt | 63 |
1 files changed, 62 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/pinctrl/fsl,imx7d-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/fsl,imx7d-pinctrl.txt index 8bbf25d..457b2c6 100644 --- a/Documentation/devicetree/bindings/pinctrl/fsl,imx7d-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/fsl,imx7d-pinctrl.txt @@ -1,16 +1,42 @@ * Freescale i.MX7 Dual IOMUX Controller +iMX7D supports two iomuxc controllers, fsl,imx7d-iomuxc controller is similar +as previous iMX SoC generation and fsl,imx7d-iomuxc-lpsr which provides low +power state retention capabilities on gpios that are part of iomuxc-lpsr +(GPIO1_IO7..GPIO1_IO0). While iomuxc-lpsr provides its own set of registers for +mux and pad control settings, it shares the input select register from main +iomuxc controller for daisy chain settings, the fsl,input-sel property extends +fsl,imx-pinctrl driver to support iomuxc-lpsr controller. + +iomuxc_lpsr: iomuxc-lpsr@302c0000 { + compatible = "fsl,imx7d-iomuxc-lpsr"; + reg = <0x302c0000 0x10000>; + fsl,input-sel = <&iomuxc>; +}; + +iomuxc: iomuxc@30330000 { + compatible = "fsl,imx7d-iomuxc"; + reg = <0x30330000 0x10000>; +}; + +Pheriparials using pads from iomuxc-lpsr support low state retention power +state, under LPSR mode GPIO's state of pads are retain. + Please refer to fsl,imx-pinctrl.txt in this directory for common binding part and usage. Required properties: -- compatible: "fsl,imx7d-iomuxc" +- compatible: "fsl,imx7d-iomuxc" for main IOMUXC controller, or + "fsl,imx7d-iomuxc-lpsr" for Low Power State Retention IOMUXC controller. - fsl,pins: each entry consists of 6 integers and represents the mux and config setting for one pin. The first 5 integers <mux_reg conf_reg input_reg mux_val input_val> are specified using a PIN_FUNC_ID macro, which can be found in imx7d-pinfunc.h under device tree source folder. The last integer CONFIG is the pad setting value like pull-up on this pin. Please refer to i.MX7 Dual Reference Manual for detailed CONFIG settings. +- fsl,input-sel: required property for iomuxc-lpsr controller, this property is + a phandle for main iomuxc controller which shares the input select register for + daisy chain settings. CONFIG bits definition: PAD_CTL_PUS_100K_DOWN (0 << 5) @@ -25,3 +51,38 @@ PAD_CTL_DSE_X1 (0 << 0) PAD_CTL_DSE_X2 (1 << 0) PAD_CTL_DSE_X3 (2 << 0) PAD_CTL_DSE_X4 (3 << 0) + +Examples: +While iomuxc-lpsr is intended to be used by dedicated peripherals to take +advantages of LPSR power mode, is also possible that an IP to use pads from +any of the iomux controllers. For example the I2C1 IP can use SCL pad from +iomuxc-lpsr controller and SDA pad from iomuxc controller as: + +i2c1: i2c@30a20000 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_i2c1_1 &pinctrl_i2c1_2>; + status = "okay"; +}; + +iomuxc-lpsr@302c0000 { + compatible = "fsl,imx7d-iomuxc-lpsr"; + reg = <0x302c0000 0x10000>; + fsl,input-sel = <&iomuxc>; + + pinctrl_i2c1_1: i2c1grp-1 { + fsl,pins = < + MX7D_PAD_GPIO1_IO04__I2C1_SCL 0x4000007f + >; + }; +}; + +iomuxc@30330000 { + compatible = "fsl,imx7d-iomuxc"; + reg = <0x30330000 0x10000>; + + pinctrl_i2c1_2: i2c1grp-2 { + fsl,pins = < + MX7D_PAD_I2C1_SDA__I2C1_SDA 0x4000007f + >; + }; +}; |