From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH v3 06/24] ARM: dts: imx6-sabrelite: add OV5642 and OV5640 camera sensors Date: Sun, 05 Feb 2017 17:24:30 +0200 Message-ID: <23975350.L90NWivx6X@avalon> References: <1483755102-24785-1-git-send-email-steve_longerbeam@mentor.com> <1483755102-24785-7-git-send-email-steve_longerbeam@mentor.com> <20170130225133.GF27898@n2100.armlinux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20170130225133.GF27898-l+eeeJia6m9URfEZ8mYm6t73F7V6hmMc@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Russell King - ARM Linux Cc: Steve Longerbeam , robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, shawnguo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, fabio.estevam-3arQi8VN3Tc@public.gmane.org, mchehab-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, hverkuil-qWit8jRvyhVmR6Xm/wNWPw@public.gmane.org, nick-gcszYUEDH4VrovVCs/uTlw@public.gmane.org, markus.heiser-m1Uo1GnMJf0b1SvskN2V4Q@public.gmane.org, p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, laurent.pinchart+renesas-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, bparrot-l0cyMroinI0@public.gmane.org, geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org, arnd-r2nGTMty4D4@public.gmane.org, sudipm.mukherjee-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, minghsiu.tsai-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, tiffany.lin-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, jean-christophe.trotin-qxv4g6HH51o@public.gmane.org, horms+renesas-/R6kz+dDXgpPR4JQBCEnsQ@public.gmane.org, niklas.soderlund+renesas-1zkq55x86MTxsAP9Fp7wbw@public.gmane.org, robert.jarzmik-GANU6spQydw@public.gmane.org, songjun.wu-UWL1GkI3JZL3oGB3hsPCZA@public.gmane.org, andrew-ct.chen-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devel-gWbeCf7V1WCQmaza687I9g@public.gmane.org List-Id: devicetree@vger.kernel.org Hi Russell, On Monday 30 Jan 2017 22:51:33 Russell King - ARM Linux wrote: > On Fri, Jan 06, 2017 at 06:11:24PM -0800, Steve Longerbeam wrote: > > + ov5640: camera@40 { > > + compatible = "ovti,ov5640"; > > + pinctrl-names = "default"; > > + pinctrl-0 = <&pinctrl_ov5640>; > > + clocks = <&mipi_xclk>; > > + clock-names = "xclk"; > > + reg = <0x40>; > > + xclk = <22000000>; > > + reset-gpios = <&gpio2 5 GPIO_ACTIVE_LOW>; /* NANDF_D5 */ > > + pwdn-gpios = <&gpio6 9 GPIO_ACTIVE_HIGH>; /* NANDF_WP_B */ > > + > > + port { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + ov5640_to_mipi_csi: endpoint@1 { > > + reg = <1>; > > + remote-endpoint = <&mipi_csi_from_mipi_sensor>; > > + data-lanes = <0 1>; > > + clock-lanes = <2>; > > How do you envision a four-lane sensor being described? > > data-lanes = <0 1 3 4>; > clock-lanes = <2>; > > ? > > The binding document for video-interfaces.txt says: > > - clock-lanes: an array of physical clock lane indexes. Position of an entry > determines the logical lane number, while the value of an entry indicates > physical lane, e.g. for a MIPI CSI-2 bus we could have "clock-lanes = > <0>;", which places the clock lane on hardware lane 0. This property is > valid for serial busses only (e.g. MIPI CSI-2). Note that for the MIPI > CSI-2 bus this array contains only one entry. > > So I think you need to have a good reason to make the clock lane non-zero. The purpose of the data-lanes and clock-lanes properties is to describe lane assignment for hardware that supports lane routing. As far as I know the OV5640 doesn't support lane routing and has dedicated pins for the clock and data lanes. The data-lanes and clock-lanes properties should probably not be specified at all. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html