From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCH 4/4] omap4-droid4: Use software debounce for gpio-keys Date: Fri, 18 May 2018 09:21:09 +0200 Message-ID: <20180518072109.GA31304@amd> References: <20180517233542.30629-1-tony@atomide.com> <20180517233542.30629-5-tony@atomide.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============0852060653437929967==" Return-path: In-Reply-To: <20180517233542.30629-5-tony@atomide.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Tony Lindgren Cc: Nishanth Menon , Tero Kristo , Grygorii Strashko , Marcel Partap , Dave Gerlach , Keerthy , Merlijn Wajer , Sebastian Reichel , Kalle Valo , NeKit , Eyal Reizer , Ash Charles , Michael Scott , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org --===============0852060653437929967== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/04w6evG8XlLl3ft" Content-Disposition: inline --/04w6evG8XlLl3ft Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > The default value of 5ms will use GPIO hardware based debounce clocks > that will keep L4PER from idling consuming about extra 30mW. >=20 > Use a value of 10ms that is above the hardware debounce maximum of > 7.95ms forcing software based debouncing. >=20 > This allows droid4 to enter PER retention during idle as long as UARTs > are idled and USB modules unloaded or unbound. >=20 > Note that there seems to be a pending issue with having droid 4 enter core > retention during idle where GPIO bank 1 needs to be reset late after init > for some reason to not block core retention. In addition to that, we are > also missing GPIO related PM runtime calls for omap4 that will be posted > separately. Thanks, will take a look. BTW, did you notice that debouncing is wrong on most of the keyboard? If you double click a key (most will do, for example "J") it will fail to recognize second release and instead of expected "jj", you get autorepeat ("jjjjjjjjjjjjjjjjjjjjjj..."). Ok, I guess main keyboard is not on GPIO... Best regards, Pavel > @@ -128,6 +128,7 @@ > gpios =3D <&gpio5 26 GPIO_ACTIVE_LOW>; /* gpio154 */ > linux,code =3D ; > linux,can-disable; > + debounce-interval =3D <10>; I'd say this subtlety is worth a comment. Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --/04w6evG8XlLl3ft Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlr+fuUACgkQMOfwapXb+vKM2wCfYZ+SzfyR8jkxdz3LbZYil93D CMAAoLGjy2ANfK2lE8yTl7t8hDaYC6Sh =vTXP -----END PGP SIGNATURE----- --/04w6evG8XlLl3ft-- --===============0852060653437929967== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============0852060653437929967==--