| Message ID | 20200602001954.30736-1-tony@atomide.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ARM: dts: omap4-droid4: Fix spi configuration and increase rate | expand |
diff --git a/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi b/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi --- a/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi +++ b/arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi @@ -13,8 +13,10 @@ cpcap: pmic@0 { #interrupt-cells = <2>; #address-cells = <1>; #size-cells = <0>; - spi-max-frequency = <3000000>; + spi-max-frequency = <9600000>; spi-cs-high; + spi-cpol; + spi-cpha; cpcap_adc: adc { compatible = "motorola,mapphone-cpcap-adc";
We can currently sometimes get "RXS timed out" errors and "EOT timed out" errors with spi transfers. These errors can be made easy to reproduce by reading the cpcap iio values in a loop while keeping the CPUs busy by also reading /dev/urandom. The "RXS timed out" errors we can fix by adding spi-cpol and spi-cpha in addition to the spi-cs-high property we already have. The "EOT timed out" errors we can fix by increasing the spi clock rate to 9.6 MHz. Looks similar MC13783 PMIC says it works at spi clock rates up to 20 MHz, so let's assume we can pick any rate up to 20 MHz also for cpcap. Cc: maemo-leste@lists.dyne.org Cc: Merlijn Wajer <merlijn@wizzup.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: Sebastian Reichel <sre@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> --- arch/arm/boot/dts/motorola-cpcap-mapphone.dtsi | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)