From mboxrd@z Thu Jan 1 00:00:00 1970 From: robh@kernel.org (Rob Herring) Date: Wed, 1 Nov 2017 16:26:59 -0500 Subject: [PATCH 2/4] pinctrl: Add skew-delay pin config and bindings In-Reply-To: <20171028133719.27528-2-linus.walleij@linaro.org> References: <20171028133719.27528-1-linus.walleij@linaro.org> <20171028133719.27528-2-linus.walleij@linaro.org> Message-ID: <20171101212659.be4phj2wha66x63d@rob-hp-laptop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, Oct 28, 2017 at 03:37:17PM +0200, Linus Walleij wrote: > Some pin controllers (such as the Gemini) can control the > expected clock skew and output delay on certain pins with a > sub-nanosecond granularity. This is typically done by shunting > in a number of double inverters in front of or behind the pin. > Make it possible to configure this with a generic binding. > > Cc: devicetree at vger.kernel.org > Signed-off-by: Linus Walleij > --- > Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt | 4 ++++ > drivers/pinctrl/pinconf-generic.c | 2 ++ > include/linux/pinctrl/pinconf-generic.h | 5 +++++ > 3 files changed, 11 insertions(+) > > diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt > index 4483cc31e531..ad9bbbba36e9 100644 > --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt > +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt > @@ -271,6 +271,10 @@ output-high - set the pin to output mode with high level > sleep-hardware-state - indicate this is sleep related state which will be programmed > into the registers for the sleep state. > slew-rate - set the slew rate > +skew-delay - this affects the expected clock skew on input pins > + and the delay before latching a value to an output > + pin. Typically indicates how many double-inverters are > + used to delay the signal. Units? > > For example: >