Compared to legacy booting, we don't have wake-up events enabled for device tree based booting. This means that if deeper idle states are enabled, the device won't wake up to UART events and seems like it has hung. Let's fix that by adding the wake-up interrupt. Note that we don't need to set the PIN_OFF_WAKEUPENABLE any longer, that's handled by the wake-up interrupt when the serial driver does request_irq on it. Tested with the following on omap3-overo-summit that has the ES2.1 omap: #!/bin/bash uarts=$(find /sys/class/tty/ttyO*/device/power/ -type d) for uart in $uarts; do echo 3000 > $uart/autosuspend_delay_ms done uarts=$(find /sys/class/tty/ttyO*/power/ -type d) for uart in $uarts; do echo enabled > $uart/wakeup echo auto > $uart/control done echo 1 > /sys/kernel/debug/pm_debug/enable_off_mode # grep -i uart /proc/interrupts 90: 1085 INTC 74 OMAP UART2 338: 5 pinctrl 366 OMAP UART2 # grep ^core_pwrdm /sys/kernel/debug/pm_debug/count core_pwrdm (ON),OFF:1654,RET:131,INA:39,ON:1825... Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- a/arch/arm/boot/dts/omap3-overo-common-peripherals.dtsi +++ b/arch/arm/boot/dts/omap3-overo-common-peripherals.dtsi @@ -36,8 +36,8 @@ uart3_pins: pinmux_uart3_pins { pinctrl-single,pins = < - OMAP3_CORE1_IOPAD(0x219e, PIN_INPUT | PIN_OFF_WAKEUPENABLE | MUX_MODE0) /* uart3_rx_irrx.uart3_rx_irrx */ - OMAP3_CORE1_IOPAD(0x21a0, PIN_OUTPUT | MUX_MODE0) /* uart3_tx_irtx.uart3_tx_irtx */ + OMAP3_CORE1_IOPAD(0x219e, PIN_INPUT | MUX_MODE0) /* uart3_rx_irrx.uart3_rx_irrx */ + OMAP3_CORE1_IOPAD(0x21a0, PIN_OUTPUT | MUX_MODE0) /* uart3_tx_irtx.uart3_tx_irtx */ >; }; }; @@ -88,6 +88,7 @@ }; &uart3 { + interrupts-extended = <&intc 74 &omap3_pmx_core OMAP3_UART3_RX>; pinctrl-names = "default"; pinctrl-0 = <&uart3_pins>; }; -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html