From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chanwoo Choi Subject: Re: [PATCH v4] extcon: gpio: Add the support for Device tree bindings Date: Tue, 31 May 2016 16:35:03 +0900 Message-ID: <574D3EA7.9080907@samsung.com> References: <1464263265-20187-1-git-send-email-vreddytalla@nvidia.com> <20160527152934.GB12024@rob-hp-laptop> <574D32D7.2090902@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-reply-to: <574D32D7.2090902@samsung.com> Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring , Venkat Reddy Talla Cc: MyungJoo Ham , Pawel Moll , Mark Rutland , Ian Campbell , devicetree@vger.kernel.org, Kumar Gala , linux-kernel@vger.kernel.org, Laxman Dewangan List-Id: devicetree@vger.kernel.org Hi Rob, On 2016=EB=85=84 05=EC=9B=94 31=EC=9D=BC 15:44, Chanwoo Choi wrote: > On 2016=EB=85=84 05=EC=9B=94 28=EC=9D=BC 00:29, Rob Herring wrote: >> On Thu, May 26, 2016 at 05:17:45PM +0530, Venkat Reddy Talla wrote: >>> Add the support for Device tree bindings of extcon-gpio driver. >>> The extcon-gpio device tree node must include the both 'extcon-id' = and >>> 'gpios' property. >> >> I think extcon bindings are a mess in general... >> >>> For example: >>> usb_cable: extcon-gpio-0 { >>> compatible =3D "extcon-gpio"; >>> extcon-id =3D ; >>> gpios =3D <&gpio6 1 GPIO_ACTIVE_HIGH>; >>> } >>> ta_cable: extcon-gpio-1 { >>> compatible =3D "extcon-gpio"; >>> extcon-id =3D ; >>> gpios =3D <&gpio3 2 GPIO_ACTIVE_LOW>; >>> debounce-ms =3D <50>; /* 50 millisecond */ >>> wakeup-source; >>> } >> >> This is all 1 logical connector, the USB connector. Why are you=20 >> describing cables? Those are not part of the h/w and are dynamic.=20 >> Describe this as a connector which is one thing (i.e. node). Use a=20 >> compatible string that reflects the type of connector=20 >> (usb-microab-connector), not the driver you want to use. Then define= =20 >> GPIO lines needed to provide state information like VBus, ID, charge= r=20 >> modes and control lines like soft connect (D+ pullup enable), VBus=20 >> enable, etc. >=20 > You're right. The extcon-gpio driver will not use the "extcon-gpio" r= aw compatible. > As you commented[1], the each connector will have the unique name to = use the extcon-gpio.c driver. > [1] https://lkml.org/lkml/2015/10/21/906 >=20 >=20 > For example, > The extcon-gpio.c driver may have the different name including the h/= w information > according to the kind of external connector. >=20 > static const struct of_device_id gpio_extcon_of_match[] =3D { > { > .compatible =3D "extcon-chg-sdp", /* SDP charger connector */ > .data =3D EXTCON_CHG_SDP_DATA, > }, { > .compatible =3D "extcon-chg-dcp", /* DCP charger connector */ > .data =3D EXTCON_CHG_DCP_DATA, > }, { > .compatible =3D "extcon-jack-microphone", /* Microphone jack connec= tor */ > .data =3D EXTCON_JACK_MICROPHONE_DATA, > }, { > .compatible =3D "extcon-disp-hdmi", /* HDMI connector*/ > .data =3D EXTCON_DISP_HDMI_DATA, > }, > ...... > }; I reply it again. The extcon-gpio.c is very similar with existing gpio_keys.c driver[1] [1] drivers/input/keyboard/gpio_keys.c The gpio_keys.c driver use the following style to support the device-tr= ee. It use the "gpio-keys" compatible and this dt node include the specific 'key code' such as 'extcon-id =3D ;' gpio_keys { compatible =3D "gpio-keys"; power_key { gpios =3D <&gpx2 7 GPIO_ACTIVE_LOW>; linux,code =3D ; label =3D "power key"; debounce-interval =3D <10>; wakeup-source; }; }; If the extcon-gpio.c driver should have the separate compatible accordi= ng to the kind of external connector, the list of compatible name of extcon-g= pio.c driver will be increased when new external connector is attached. The extcon-gpio.c driver can separate the kind of external connector by using the 'extcon-id' property.=20 Thanks, Chanwoo Choi