2019-08-20 03:09:51

by Andrey Smirnov

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

Fiber-optic module attached to the bus is only rated to work at
100kHz, so drop the bus frequncy to accomodate 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]
---
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

2019-08-20 14:11:29

by Chris Healy

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

On Mon, Aug 19, 2019 at 8:08 PM Andrey Smirnov <[email protected]> wrote:
>
> Fiber-optic module attached to the bus is only rated to work at
> 100kHz, so drop the bus frequncy to accomodate 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]
> ---
> 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
>

Reviewed-by: Chris Healy <[email protected]>

2019-08-20 14:41:00

by Marc Gonzalez

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

On 20/08/2019 05:08, Andrey Smirnov wrote:

> Fiber-optic module attached to the bus is only rated to work at
> 100kHz, so drop the bus frequncy to accomodate that.

s/100kHz/100 kHz
s/frequncy/frequency
s/accomodate/accommodate

Regards.

2019-08-20 15:32:22

by Andrew Lunn

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

On Mon, Aug 19, 2019 at 08:08:04PM -0700, Andrey Smirnov wrote:
> Fiber-optic module attached to the bus is only rated to work at
> 100kHz, so drop the bus frequncy to accomodate that.

Hi Andrey

Did you review all the other ZII platforms? I could imaging the same
problem happening else where.

Thanks
Andrew

2019-08-21 01:31:30

by Andrey Smirnov

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

On Tue, Aug 20, 2019 at 7:41 AM Marc Gonzalez <[email protected]> wrote:
>
> On 20/08/2019 05:08, Andrey Smirnov wrote:
>
> > Fiber-optic module attached to the bus is only rated to work at
> > 100kHz, so drop the bus frequncy to accomodate that.
>
> s/100kHz/100 kHz
> s/frequncy/frequency
> s/accomodate/accommodate
>

Will fix in v2.

Thanks,
Andrey Smirnov

2019-08-21 01:57:51

by Andrey Smirnov

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

On Tue, Aug 20, 2019 at 8:29 AM Andrew Lunn <[email protected]> wrote:
>
> On Mon, Aug 19, 2019 at 08:08:04PM -0700, Andrey Smirnov wrote:
> > Fiber-optic module attached to the bus is only rated to work at
> > 100kHz, so drop the bus frequncy to accomodate that.
>
> Hi Andrey
>
> Did you review all the other ZII platforms? I could imaging the same
> problem happening else where.
>

Yes, AFAICT, fiber-optic modules are present only on SCU4
(vf610-zii-scu4-aib.dts), CFU1 (vf610-zii-cfu1.dts) and VF610 Dev
board rev. B/C (vf610-zii-dev*.dts[i]). Of all three only CFU1 has
corresponding I2C bus running @ 400 kHz.

Thanks,
Andrey Smirnov