lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230728173438.12995-2-a-bhatia1@ti.com>
Date:   Fri, 28 Jul 2023 23:04:31 +0530
From:   Aradhya Bhatia <a-bhatia1@...com>
To:     Nishanth Menon <nm@...com>, Vignesh Raghavendra <vigneshr@...com>,
        Tero Kristo <kristo@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Conor Dooley <conor+dt@...nel.org>
CC:     Devicetree List <devicetree@...r.kernel.org>,
        Linux Kernel List <linux-kernel@...r.kernel.org>,
        Linux ARM Kernel List <linux-arm-kernel@...ts.infradead.org>,
        Tomi Valkeinen <tomi.valkeinen@...asonboard.com>,
        Rahul T R <r-ravikumar@...com>,
        Devarsh Thakkar <devarsht@...com>,
        Jai Luthra <j-luthra@...com>,
        Jayesh Choudhary <j-choudhary@...com>,
        Aradhya Bhatia <a-bhatia1@...com>
Subject: [PATCH v3 1/8] arm64: dts: ti: k3-am62x-sk-common: Update main-i2c1 frequency

The Display Data Channel (DDC) transactions between an HDMI transmitter
(SIL9022A in this case) and an HDMI monitor, occur at a maximum of
100KHz. That's the maximum supported frequency within DDC standards.

While the SIL9022A can transact with the core at 400KHz, it needs to
drop the frequency to 100KHz when communicating with the monitor,
otherwise, the i2c controller times out and shows warning like this.

[  985.773431] omap_i2c 20010000.i2c: controller timed out

That feature, however, has not been enabled in the SIL9022 driver.

Since, dropping the frequency doesn't affect any other devices on the
bus, drop the main-i2c1 frequency from 400KHz to 100KHz.

Signed-off-by: Aradhya Bhatia <a-bhatia1@...com>
---
 arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
index 34c8ffc553ec..540ed8a0d7fb 100644
--- a/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62x-sk-common.dtsi
@@ -300,7 +300,7 @@ &main_i2c1 {
 	status = "okay";
 	pinctrl-names = "default";
 	pinctrl-0 = <&main_i2c1_pins_default>;
-	clock-frequency = <400000>;
+	clock-frequency = <100000>;
 
 	tlv320aic3106: audio-codec@1b {
 		#sound-dai-cells = <0>;
-- 
2.40.1

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ