LinuxLists.cc - [PATCH v2] ARM: dts: vf610-zii-cfu1: Slow I2C0 down to 100 kHz

2019-08-21 02:18:09

Subject: [PATCH v2] ARM: dts: vf610-zii-cfu1: Slow I2C0 down to 100 kHz

Fiber-optic modules attached to the bus are only rated to work at
100 kHz, so decrease the bus frequency to accommodate that.

Signed-off-by: Andrey Smirnov <[email protected]>
Cc: Shawn Guo <[email protected]>
Cc: Chris Healy <[email protected]>
Cc: Fabio Estevam <[email protected]>
Cc: [email protected]
Cc: [email protected]
---

Changes since [v1]:

- Spelling fixes

[v1] lore.kernel.org/lkml/[email protected]

arch/arm/boot/dts/vf610-zii-cfu1.dts | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/vf610-zii-cfu1.dts b/arch/arm/boot/dts/vf610-zii-cfu1.dts
index ff460a1de85a..28732249cfc0 100644
--- a/arch/arm/boot/dts/vf610-zii-cfu1.dts
+++ b/arch/arm/boot/dts/vf610-zii-cfu1.dts
@@ -207,7 +207,7 @@
};

&i2c0 {
- clock-frequency = <400000>;
+ clock-frequency = <100000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c0>;
status = "okay";
--
2.21.0

2019-08-21 17:39:52

by Andrew Lunn

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Subject: Re: [PATCH v2] ARM: dts: vf610-zii-cfu1: Slow I2C0 down to 100 kHz

On Tue, Aug 20, 2019 at 06:39:36PM -0700, Andrey Smirnov wrote:
> Fiber-optic modules attached to the bus are only rated to work at
> 100 kHz, so decrease the bus frequency to accommodate that.
>
> Signed-off-by: Andrey Smirnov <[email protected]>
> Cc: Shawn Guo <[email protected]>
> Cc: Chris Healy <[email protected]>
> Cc: Fabio Estevam <[email protected]>
> Cc: [email protected]
> Cc: [email protected]

Reviewed-by: Andrew Lunn <[email protected]>

I took a quick look at some of the SFP standards. 100KHz is part of
the standard. So we should try to remember to keep an eye of this as
other boards are merged.

Andrew

2019-08-24 19:26:58

by Shawn Guo

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