• Tony Lindgren's avatar
    ARM: dts: Improve omap l4per idling with wlcore edge sensitive interrupt · 572cf7d7
    Tony Lindgren authored
    The wl1835mod.pdf data sheet says this pretty clearly for WL_IRQ line:
    
    "WLAN SDIO out-of-band interrupt line. Set to rising edge (active high)
    by default."
    
    And it seems this interrupt can be optionally configured to use falling
    edge too since commit bd763482 ("wl18xx: wlan_irq: support platform
    dependent interrupt types").
    
    On omap4, if the wlcore interrupt is configured as level instead of edge,
    L4PER will stop doing hardware based idling after ifconfig wlan0 down is
    done and the WL_EN line is pulled down.
    
    The symptoms show up with L4PER status registers no longer showing the
    IDLEST bits as 2 but as 0 for all the active GPIO banks and for
    L4PER_CLKCTRL. Also the l4per_pwrdm RET count stops increasing in
    the /sys/kernel/debug/pm_debug/count.
    
    While there is also probably a GPIO related issue that needs to be
    still fixed, this change gets us to the point where we can have L4PER
    idling.
    
    I'm guessing wlcore was at some point configured to use level interrupts
    because of edge handling issues in gpio-omap. However, with the recent
    fixes to gpio-omap the edge interrupts seem to be working just fine.
    
    Let's change it for all omap boards with wlcore interrupt set as level.
    
    Cc: Dave Gerlach <d-gerlach@ti.com>
    Cc: Eyal Reizer <eyalr@ti.com>
    Cc: Grygorii Strashko <grygorii.strashko@ti.com>
    Cc: Kalle Valo <kvalo@codeaurora.org>
    Cc: Nishanth Menon <nm@ti.com>
    Cc: Tero Kristo <t-kristo@ti.com>
    [tony@atomide.com updated comments a bit for gpio issue]
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
    572cf7d7
omap4-var-som-om44-wlan.dtsi 2.34 KB