From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 1/3] gpio: Add simple poweroff-gpio driver Date: Mon, 12 Nov 2012 09:17:48 -0700 Message-ID: <50A1212C.2080601@wwwdotorg.org> References: <1352650891-18356-1-git-send-email-andrew@lunn.ch> <1352650891-18356-2-git-send-email-andrew@lunn.ch> <50A020C5.4070506@wwwdotorg.org> <20121112082546.GU22029@lunn.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20121112082546.GU22029-g2DYL2Zd6BY@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: Andrew Lunn Cc: gmbnomis-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, jm-Pj/HzkgeCk7QXOPxS62xeg@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Jason Cooper List-Id: devicetree@vger.kernel.org On 11/12/2012 01:25 AM, Andrew Lunn wrote: > On Sun, Nov 11, 2012 at 03:03:49PM -0700, Stephen Warren wrote: >> On 11/11/2012 09:21 AM, Andrew Lunn wrote: >>> From: Jamie Lentin >>> >>> Given appropriate devicetree bindings, this driver registers a >>> pm_power_off function to set a GPIO line high/low to power down >>> your board. >>> diff --git a/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt b/Documentation/devicetree/bindings/gpio/gpio-poweroff.txt >> >>> +Required properties: >>> +- compatible : should be "gpio-poweroff". >>> +- gpios : The GPIO to set high/low, see "gpios property" in >>> + Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be >>> + low to power down the board set it to "Active Low", otherwise set >>> + gpio to "Active High". >> >> Unfortunately, not all GPIO bindings support active high/low flags in >> the GPIO specifier. As such, the flags there are basically useless. >> Other bindings (e.g. IIRC the fixed-regulator binding) have added a >> separate active-high property to indicate the GPIO polarity. This >> binding should probably follow suite. > > Humm, so are you saying of_get_named_gpio_flags() is deprecated? I don't know if it's deprecated, but it's certainly not useful in generic code. > There is a lot of code using this to get the flag > OF_GPIO_ACTIVE_LOW. Some of these users are very generic code: That's unfortunate... > > drivers/leds/leds-gpio.c: > drivers/input/misc/rotary_encoder.c: > drivers/input/keyboard/gpio_keys.c: > drivers/input/keyboard/gpio_keys_polled.c: > drivers/hwmon/gpio-fan.c: > > The only code using the "enable-active-high" > property is drivers/regulator/fixed.c although the binding > documentation twl6040.txt talks about it, but the code does not > implement it. > > Could you point me towards some email discussion about this? I don't have any good links. I imagine the discussion happened when the patched for regulator/fixed.c were submitted.