Hi Laurent and Paul On Thu, 1 Sept 2022 at 14:23, Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx> wrote: > > Hi Laurent, > > On Thu 01 Sep 22, 16:00, Laurent Pinchart wrote: > > On Thu, Sep 01, 2022 at 02:49:43PM +0200, Paul Kocialkowski wrote: > > > On Fri 26 Aug 22, 22:08, Laurent Pinchart wrote: > > > > On Fri, Aug 26, 2022 at 08:28:03PM +0200, Paul Kocialkowski wrote: > > > > > From: Kévin L'hôpital <kevin.lhopital@xxxxxxxxxxx> > > > > > > > > > > The Bananapi M3 supports a camera module which includes an OV8865 sensor > > > > > connected via the parallel CSI interface and an OV8865 sensor connected > > > > > via MIPI CSI-2. > > > > > > > > > > The I2C2 bus is shared by the two sensors as well as the (active-low) > > > > > reset signal, but each sensor has it own shutdown line. > > > > > > > > I see a single sensor in this file, am I missing something ? > > > > > > Indeed this patch only adds the OV8865, not the OV5640 which is also present > > > on the same camera board extension. > > > > > > A patch was submitted some time ago adding support for (only) the OV5640: > > > https://lore.kernel.org/lkml/20190408165744.11672-7-wens@xxxxxxxxxx/ > > > > OK. That's fine, let's just reword the commit message. > > Sure. > > > > > Sounds like a perfect candidate for an overlay, it could then be merged > > > > upstream. > > > > > > Do we have an upstream place to merge device-tree overlays now? > > > > They're accepted in the upstream kernel as far as I know, a git grep for > > /plugin/ in .dts files produces 18 matches. > > Oh okay, definitely good to know thanks! > > > > I'll check if it's possible to describe both sensors together and actually > > > be able to select one or the other properly from userspace. Last time I tried > > > this wasn't possible: there's at least the shared reset GPIO used by both > > > sensors, which cannot be requested by the two drivers in parallel. > > > > > > To be honest this is very poor hardware design and it was almost certainly > > > designed with the idea that only one sensor will be configured per boot. > > > See https://wiki.banana-pi.org/Camera and > > > https://drive.google.com/file/d/0B4PAo2nW2KfnOEFTMjZ2aEVGUVU/view?usp=sharing > > > for the schematics pdf > > > > It's not great indeed, but not that uncommon either (unfortunately). I > > wonder if we need some kind of reset GPIO API, but that would be a hack > > at most I think. > > Yeah I don't see any obvious clean solution here. > But that could still be two separate dt overlays for now. Just to throw the idea out there, (ab)use the regulator API so that they share a regulator-gpio device that claims that GPIO. When either sensor requests the regulator, the reset line will get pulled to the appropriate state. Dave > > > > > Signed-off-by: Kévin L'hôpital <kevin.lhopital@xxxxxxxxxxx> > > > > > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx> > > > > > --- > > > > > arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts | 102 +++++++++++++++++++ > > > > > 1 file changed, 102 insertions(+) > > > > > > > > > > diff --git a/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts b/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts > > > > > index 5a7e1bd5f825..80fd99cf24b2 100644 > > > > > --- a/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts > > > > > +++ b/arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts > > > > > @@ -85,6 +85,30 @@ led-1 { > > > > > }; > > > > > }; > > > > > > > > > > + reg_ov8865_avdd: ov8865-avdd { > > > > > + compatible = "regulator-fixed"; > > > > > + regulator-name = "ov8865-avdd"; > > > > > + regulator-min-microvolt = <2800000>; > > > > > + regulator-max-microvolt = <2800000>; > > > > > + vin-supply = <®_dldo4>; > > > > > + }; > > > > > + > > > > > + reg_ov8865_dovdd: ov8865-dovdd { > > > > > + compatible = "regulator-fixed"; > > > > > + regulator-name = "ov8865-dovdd"; > > > > > + regulator-min-microvolt = <2800000>; > > > > > + regulator-max-microvolt = <2800000>; > > > > > + vin-supply = <®_dldo4>; > > > > > + }; > > > > > + > > > > > + reg_ov8865_dvdd: ov8865-dvdd { > > > > > + compatible = "regulator-fixed"; > > > > > + regulator-name = "ov8865-dvdd"; > > > > > + regulator-min-microvolt = <1200000>; > > > > > + regulator-max-microvolt = <1200000>; > > > > > + vin-supply = <®_eldo1>; > > > > > + }; > > > > > > > > Are those three regulators on the Banana Pi, or on the camera module ? > > > > > > That's on the camera module. > > > > > > > > + > > > > > reg_usb1_vbus: reg-usb1-vbus { > > > > > compatible = "regulator-fixed"; > > > > > regulator-name = "usb1-vbus"; > > > > > @@ -115,6 +139,23 @@ &cpu100 { > > > > > cpu-supply = <®_dcdc3>; > > > > > }; > > > > > > > > > > +&csi { > > > > > + status = "okay"; > > > > > + > > > > > + ports { > > > > > + #address-cells = <1>; > > > > > + #size-cells = <0>; > > > > > + > > > > > + port@1 { > > > > > + reg = <1>; > > > > > > > > All of this (except the status = "okay") should go to sun8i-a83t.dtsi. > > > > > > > > > + > > > > > + csi_in_mipi_csi2: endpoint { > > > > > + remote-endpoint = <&mipi_csi2_out_csi>; > > > > > + }; > > > > > > > > This too actually, once the issue mentioned in patch 5/6 gets fixed. > > > > > > > > > + }; > > > > > + }; > > > > > +}; > > > > > + > > > > > &de { > > > > > status = "okay"; > > > > > }; > > > > > @@ -147,6 +188,36 @@ hdmi_out_con: endpoint { > > > > > }; > > > > > }; > > > > > > > > > > +&i2c2 { > > > > > + pinctrl-names = "default"; > > > > > + pinctrl-0 = <&i2c2_pe_pins>; > > > > > > > > This looks like a candidate for upstreaming in > > > > sun8i-a83t-bananapi-m3.dts, it shouldn't be in the overlay. > > > > > > I2C2 is actually also exported in the PH pins, which is available on the board > > > header, so it's not obvious that using the PE pins should be the default. > > > > > > The context is that Allwinner SoCs usually have a dedicated I2C controller for > > > cameras, but also route a "generic" I2C controller on the same pins. > > > > Out of curiosity, what features do those dedicated camera I2C > > controllers provide, compared to "normal" I2C controllers ? > > IIRC there's some feature to send i2c messages synced with the camera interface > vsync signal, to have some kind of hardware atomic mechanism for reconfiguring > a sensor. > > Not sure that's very relevant for us and an implementation for it would probably > just support regular I2C. We can probably achieve simialr results with the > request API. > > > > Here that's on the PE14/15 pins. Since we don't have mainline support for this > > > camera-dedicated I2C controller, we end up routing the generic one to the PE > > > pins, which are routed to the camera connector. > > > > OK. > > > > > In the future we could add support for this camera-dedicated controller, which > > > would then allow routing i2c2 to the PH pins independently. This is what the > > > downstream Allwinner BSP kernel does. > > > > > > > > + status = "okay"; > > > > > + > > > > > + ov8865: camera@36 { > > > > > + compatible = "ovti,ov8865"; > > > > > + reg = <0x36>; > > > > > + pinctrl-names = "default"; > > > > > + pinctrl-0 = <&csi_mclk_pin>; > > > > > + clocks = <&ccu CLK_CSI_MCLK>; > > > > > + assigned-clocks = <&ccu CLK_CSI_MCLK>; > > > > > + assigned-clock-rates = <24000000>; > > > > > + avdd-supply = <®_ov8865_avdd>; > > > > > + dovdd-supply = <®_ov8865_dovdd>; > > > > > + dvdd-supply = <®_ov8865_dvdd>; > > > > > + powerdown-gpios = <&pio 4 17 GPIO_ACTIVE_LOW>; /* PE17 */ > > > > > + reset-gpios = <&pio 4 16 GPIO_ACTIVE_LOW>; /* PE16 */ > > > > > + > > > > > + port { > > > > > + ov8865_out_mipi_csi2: endpoint { > > > > > + data-lanes = <1 2 3 4>; > > > > > + link-frequencies = /bits/ 64 <360000000>; > > > > > + > > > > > + remote-endpoint = <&mipi_csi2_in_ov8865>; > > > > > + }; > > > > > + }; > > > > > + }; > > > > > +}; > > > > > + > > > > > &mdio { > > > > > rgmii_phy: ethernet-phy@1 { > > > > > compatible = "ethernet-phy-ieee802.3-c22"; > > > > > @@ -154,6 +225,24 @@ rgmii_phy: ethernet-phy@1 { > > > > > }; > > > > > }; > > > > > > > > > > +&mipi_csi2 { > > > > > + status = "okay"; > > > > > +}; > > > > > + > > > > > +&mipi_csi2_in { > > > > > + mipi_csi2_in_ov8865: endpoint { > > > > > + data-lanes = <1 2 3 4>; > > > > > + > > > > > + remote-endpoint = <&ov8865_out_mipi_csi2>; > > > > > + }; > > > > > +}; > > > > > + > > > > > +&mipi_csi2_out { > > > > > + mipi_csi2_out_csi: endpoint { > > > > > + remote-endpoint = <&csi_in_mipi_csi2>; > > > > > + }; > > > > > +}; > > > > > + > > > > > &mmc0 { > > > > > pinctrl-names = "default"; > > > > > pinctrl-0 = <&mmc0_pins>; > > > > > @@ -327,11 +416,24 @@ ®_dldo3 { > > > > > regulator-name = "vcc-pd"; > > > > > }; > > > > > > > > > > +®_dldo4 { > > > > > + regulator-always-on; > > > > > > > > Does it have to be always on ? > > > > > > Mhh so I realize the regulators handling here is quite messy. > > > I guess I didn't do such a good review of this patch internally. > > > > > > The situation is that the regulators on the camera board all have their > > > enable pin tied to the DLDO4 output, but that would be best described as > > > a vin-supply of the ov8865 regulators above. Their real vin supply is an > > > always-on board-wide power source but I don't think we can represent another > > > regulator acting as enable signal in a better way. > > > > That's right. I've modeled that as a parent regulator in the past, even > > if it doesn't reflect the exact hardware topology, it's functionally > > equivalent. > > Sounds good, I'll change it that way. > > Cheers, > > Paul > > > > Now beware that the camera board schematics are confusing as they show resistors > > > (R17, R18, R19, R20, R23) connecting some power lines together, but they are not > > > populated on the board (I guess the point is to make a variant of the design > > > without regulators on the camera board and to use ones from the PMU instead). > > > This probably confused Kevin and I back when this patch was made. > > > > > > > > + regulator-min-microvolt = <2800000>; > > > > > + regulator-max-microvolt = <2800000>; > > > > > + regulator-name = "avdd-csi"; > > > > > > > > Doesn't this belong to the base board .dts ? Same below. > > > > > > > > > +}; > > > > > + > > > > > ®_drivevbus { > > > > > regulator-name = "usb0-vbus";AVDD-CSI > > > > > status = "okay"; > > > > > }; > > > > > > > > > > +®_eldo1 { > > > > > + regulator-min-microvolt = <1200000>; > > > > > + regulator-max-microvolt = <1200000>; > > > > > + regulator-name = "dvdd-csi-r"; > > > > > +}; > > > > > + > > > > > ®_fldo1 { > > > > > regulator-min-microvolt = <1080000>; > > > > > regulator-max-microvolt = <1320000>; > > > > -- > > Regards, > > > > Laurent Pinchart > > -- > Paul Kocialkowski, Bootlin > Embedded Linux and kernel engineering > https://bootlin.com
