Thread (13 messages) 13 messages, 3 authors, 2018-12-19

Re: [PATCH 5/5] arm64: dts: allwinner: a64-amarula-relic: Add OV5640 camera node

From: Rob Herring <robh@kernel.org>
Date: 2018-12-19 15:58:26
Also in: linux-devicetree, linux-media, lkml

On Thu, Dec 06, 2018 at 04:43:33PM +0530, Jagan Teki wrote:
On Mon, Dec 3, 2018 at 3:55 PM Chen-Yu Tsai [off-list ref] wrote:
quoted
On Mon, Dec 3, 2018 at 6:08 PM Jagan Teki [off-list ref] wrote:
quoted
Amarula A64-Relic board by default bound with OV5640 camera,
so add support for it with below pin information.

- PE13, PE12 via i2c-gpio bitbanging
- CLK_CSI_MCLK as external clock
- PE1 as external clock pin muxing
- DLDO3 as vcc-csi supply
- DLDO3 as AVDD supply
- ALDO1 as DOVDD supply
- ELDO3 as DVDD supply
- PE14 gpio for reset pin
- PE15 gpio for powerdown pin

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 .../allwinner/sun50i-a64-amarula-relic.dts    | 54 +++++++++++++++++++
 arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi |  5 ++
 2 files changed, 59 insertions(+)
diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64-amarula-relic.dts b/arch/arm64/boot/dts/allwinner/sun50i-a64-amarula-relic.dts
index 6cb2b7f0c817..9ac6d773188b 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-a64-amarula-relic.dts
+++ b/arch/arm64/boot/dts/allwinner/sun50i-a64-amarula-relic.dts
@@ -22,6 +22,41 @@
                stdout-path = "serial0:115200n8";
        };

+       i2c-csi {
+               compatible = "i2c-gpio";
+               sda-gpios = <&pio 4 13 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
+               scl-gpios = <&pio 4 12 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>;
FYI our hardware doesn't do open drain.
True, but the kernel is enforcing it seems, from the change from [1].
does that mean Linux use open drain even though hardware doens't have?
or did I miss anything?
It's forced because you can't do I2C without open drain. Things like the 
slave doing clock stretching won't work.

Rob

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