UART RX wakeup from sleep not working

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Hi,

  I'm having trouble getting the UART wakeup from sleep via activity
on the RX pin working.

--------------------------------------------------------
Assumptions (using UART3)

1. Using Arago Linux 2.6.32
2. OMAP3730 is in sleep mode via
   echo 1 > /mnt/dbg/pm_debug/sleep_while_idle
3. The UARTi.SCR_REG[4] RX_CTS_WU_EN bit is set to 1.
4. The UARTi.IER_REG[4] SLEEP_MODE bit to 1
5. The UARTi.SYSC_REG[2] ENAWAKEUP bit is set to 1
6. The UARTi.WER_REG EVENT_4_RX_ACTIVITY bit is set to 1
7. The UARTi.SSR_REG RX_CTS_DSR_WAKE_UP_STS bit is set to 1

Expectations

  When a character arrives on the RX pin of UART3 when in sleep mode,
the OMAP3730 exits sleep mode immediately via a RX_CTS_DSR_WAKE_UP
interrupt.

Problem

  The interrupt does happen but only after the UART clocks have been
enabled.  The OMAP3730 seems to exit sleep mode only when the UART
clocks are re-enabled via omap_uart_enable_clocks() in
arch/arm/mach-omap2/serial.c
--------------------------------------------------------

  Any help greatly appreciated.

  Rick
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