From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Reichel Subject: Re: [PATCH v4 01/16] dt-bindings: mtd: gpmc-onenand: Update properties description Date: Wed, 15 Nov 2017 16:42:11 +0100 Message-ID: <20171115154210.i3nbt2czpma6hi2w@earth> References: <20171111211656.neoypp7gdyfasteg@lenoch> <20171115134339.jnvu6asy2srxsuko@earth> <20171115151206.g76k75lwq2jlezki@lenoch> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============5245291102160865442==" Return-path: In-Reply-To: <20171115151206.g76k75lwq2jlezki@lenoch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+gldm-linux-mtd-36=gmane.org@lists.infradead.org To: Ladislav Michl Cc: Boris Brezillon , Tony Lindgren , Peter Ujfalusi , Kyungmin Park , linux-mtd@lists.infradead.org, linux-omap@vger.kernel.org, Roger Quadros List-Id: linux-omap@vger.kernel.org --===============5245291102160865442== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="myco2e2365k2z6mh" Content-Disposition: inline --myco2e2365k2z6mh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, On Wed, Nov 15, 2017 at 04:12:06PM +0100, Ladislav Michl wrote: > On Wed, Nov 15, 2017 at 02:43:39PM +0100, Sebastian Reichel wrote: > > Hi, > >=20 > > On Sat, Nov 11, 2017 at 10:16:56PM +0100, Ladislav Michl wrote: > > > Compatible property is required for OMAP2+ mtd driver. Also > > > add R/B pin gpio description and delete unused dma-channel > > > property. > > >=20 > > > Signed-off-by: Ladislav Michl > > > --- > > > Changes: > > > -v4: new patch > > >=20 > > > Documentation/devicetree/bindings/mtd/gpmc-onenand.txt | 6 ++++-- > > > 1 file changed, 4 insertions(+), 2 deletions(-) > > >=20 > > > diff --git a/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt b= /Documentation/devicetree/bindings/mtd/gpmc-onenand.txt > > > index b6e8bfd024f4..9d7b1409deab 100644 > > > --- a/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt > > > +++ b/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt > > > @@ -9,13 +9,14 @@ Documentation/devicetree/bindings/memory-controller= s/omap-gpmc.txt > > > =20 > > > Required properties: > > > =20 > > > + - compatible: "ti,omap2-onenand" > >=20 > > I suggest to also add more specific compatible values (i.e. > > "ti,omap3-onenand") in case it is needed later. They don't > > hurt much and may prevent ugly hacks in the future. >=20 > We tried hard to avoid anything omap3 specific (it was present in earlier > versions of this patchset). And NAND driver is also okay with "ti,omap3-n= and" > (I know it is a poor argument). So far all OMAP2/3 differences seems to c= ome > from both devices unavailable to the person who did the code change. >=20 > While I agree it is in general good idea, I have personal problem with th= at > as there are devices in field with "ti,omap2-onenand" compatible and OMAP= 3530. >=20 > See this function: > http://git.denx.de/?p=3Du-boot.git;a=3Dblob;f=3Dboard/isee/igep00x0/igep0= 0x0.c;h=3D5c7f2567118a1e17bdb6f76f29a7161628776bf7;hb=3DHEAD#l158 > Board comes either with NAND or OneNAND, bootloader detects that and > enables proper node. Updating bootloader is potentially dangerous, so I'd > like to avoid that. >=20 > However, if you insist on idea above, I'm okay with keeping some of tree > patches for a while... The best practice for DT bindings is to have a specific compatible and a generic fallback. Something like compatible =3D "ti,omap3-onenand", "ti,omap2-onenand"; You can just ignore the "ti,omap3-onenand" in the driver for now. Just add it to the bindings and the DTS files. Then it is there in case it is needed at some point. -- Sebastian > > > - reg: The CS line the peripheral is connected to > > > - - gpmc,device-width Width of the ONENAND device connected to the GP= MC > > > + - gpmc,device-width: Width of the ONENAND device connected to the G= PMC > > > in bytes. Must be 1 or 2. > > > =20 > > > Optional properties: > > > =20 > > > - - dma-channel: DMA Channel index > > > + - rb-gpios: GPIO specifier for the ready/busy# pin. > > > =20 > > > For inline partition table parsing (optional): > > > =20 > > > @@ -35,6 +36,7 @@ Example for an OMAP3430 board: > > > #size-cells =3D <1>; > > > =20 > > > onenand@0 { > > > + compatible =3D "ti,omap2-onenand"; > > > reg =3D <0 0 0>; /* CS0, offset 0 */ > > > gpmc,device-width =3D <2>; > > > =20 > >=20 > > -- Sebastian >=20 >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --myco2e2365k2z6mh Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE72YNB0Y/i3JqeVQT2O7X88g7+poFAloMYFAACgkQ2O7X88g7 +pqi4g//Rh3PZvaqWjJ4VqMBRVaI4Ix+PyUGPQhCWRUpK+Ql75E5TPJnB2Vtik1O deXXAPqqzxAkHq2Lv+xHchTl4ZL/PGosKt/FjHx14kD/0Cwk5DLNL+FZI3u2laGn A00QAo5dFdPUzMNDp+l6mUiandBkYWMJfnDOA1/H0MIK+uAC9WlWTKecT4Z66Aom N0mD8HK72KOVY3h2GNmY42sjbWf8tt1XUkMdWsOzRsNsx1+6QlFv0IpIKPveu4lc vEd3G1rmZkzDM6lW+OP2r7MhFSie/hhViixZtmR4faGV2Ro6d/NH2Sm/gKmFHFGr CMLhJMMQ4rP6MY4KB0wqpINOLACpWAnOQXRwYZnZYnK/zNqzs7CoRwMok6o2HUPt jHf8kPIVNbOLM5yj3oehu1szUP1b+ljtIxwMtV+yITUiiaPXHSG/F0zBlikE+HnU 5k2I/h9LudoLH4ahVNh83VjFONnR0/0IxTXctY4kvh7Em+o8Z4WKK0FFuMEzSzfQ 3fImgqeDF/aXEKhr97eMJIRPVhyVJPHlRH6/Xw11qU1qARfRqdgRzKaiaHjipN0u IiD91vQTA7E/Z+NsFnG8k0OXhHVANfv3cYNdiQCyDdN3ujrsG95cvcDt1uYnEk06 ue0f0QRaAzwjY5Ov9AKwoCg8Engj9+3oGE3oidS0+wekr5eUSIE= =m+mh -----END PGP SIGNATURE----- --myco2e2365k2z6mh-- --===============5245291102160865442== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ --===============5245291102160865442==--