• Tony Lindgren's avatar
    ARM: dts: omap4-droid4: Fix spi configuration and increase rate · 0df12a01
    Tony Lindgren authored
    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: default avatarTony Lindgren <tony@atomide.com>
    0df12a01
motorola-cpcap-mapphone.dtsi 6.47 KB