From: Fabio Estevam <festevam@gmail.com>
To: shawnguo@kernel.org
Cc: linux-arm-kernel@lists.infradead.org, cphealy@gmail.com,
Fabio Estevam <festevam@gmail.com>,
linux-imx@nxp.com, kernel@pengutronix.de
Subject: [PATCH] arm64: dts: imx8mq-zii-ultra: Operate I2C at 100kHz
Date: Mon, 13 May 2019 11:02:59 -0300 [thread overview]
Message-ID: <20190513140259.17525-1-festevam@gmail.com> (raw)
According to the i.MX8M errata document [1], there is an I2C spec
violation when the I2C clock frequency is 400 kHz:
"e7805: I2C: When the I2C clock speed is configured for 400 kHz, the
SCL low period violates the I2C spec of 1.3 uS min"
Avoid this problem by running I2C at 100 kHz instead.
[1] https://www.nxp.com/docs/en/errata/IMX8MDQLQ_1N14W.pdf
Signed-off-by: Fabio Estevam <festevam@gmail.com>
---
arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi b/arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi
index 7a1706f969f0..8603fb1a78d0 100644
--- a/arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mq-zii-ultra.dtsi
@@ -253,14 +253,14 @@
};
&i2c1 {
- clock-frequency = <400000>;
+ clock-frequency = <100000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c1>;
status = "okay";
};
&i2c2 {
- clock-frequency = <400000>;
+ clock-frequency = <100000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c2>;
status = "okay";
@@ -376,7 +376,7 @@
};
&i2c4 {
- clock-frequency = <400000>;
+ clock-frequency = <100000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c4>;
status = "okay";
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2019-05-13 14:03 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-13 14:02 Fabio Estevam [this message]
2019-05-13 14:07 ` [PATCH] arm64: dts: imx8mq-zii-ultra: Operate I2C at 100kHz Lucas Stach
2019-05-14 12:11 ` Fabio Estevam
2019-05-23 13:19 ` Angus Ainslie
2019-05-23 15:01 ` Lucas Stach
2019-06-27 15:35 ` Chris Healy
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190513140259.17525-1-festevam@gmail.com \
--to=festevam@gmail.com \
--cc=cphealy@gmail.com \
--cc=kernel@pengutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-imx@nxp.com \
--cc=shawnguo@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.