The patch titled atmel_serial: update the powersave handler to match serial core has been added to the -mm tree. Its filename is atmel_serial-update-the-powersave-handler-to-match-serial-core.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: atmel_serial: update the powersave handler to match serial core From: Anti Sullin <anti.sullin@xxxxxxxxxxxxxx> This problem seems to be unnoticed so far: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b3b708fa2780cd2b5d8266a8f0c3a1cab364d4d2 has changed the serial core behavior to not to suspend the port if the device is enabled as a wakeup source. If the AT91 system goes to slow clock mode, the port should be suspended always and the clocks should be switched off. The patch attached updates the atmel_serial driver to match the changes in serial core. Also, the interrupts are disabled when the clock is disabled. If we disable the clock with interrupts enabled, an interrupt may get stuck. If this is the DBGU interrupt, this blocks the OR logic at system controller and thus all other sysc interrupts. Signed-off-by: Anti Sullin <anti.sullin@xxxxxxxxxxxxxx> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@xxxxxxxxx> Cc: Michael Trimarchi <trimarchimichael@xxxxxxxx> Cc: Andrew Victor <linux@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/serial/atmel_serial.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) diff -puN drivers/serial/atmel_serial.c~atmel_serial-update-the-powersave-handler-to-match-serial-core drivers/serial/atmel_serial.c --- a/drivers/serial/atmel_serial.c~atmel_serial-update-the-powersave-handler-to-match-serial-core +++ a/drivers/serial/atmel_serial.c @@ -131,7 +131,8 @@ struct atmel_uart_char { struct atmel_uart_port { struct uart_port uart; /* uart */ struct clk *clk; /* uart clock */ - unsigned short suspended; /* is port suspended? */ + int may_wakeup; /* cached value of device_may_wakeup for times we need to disable it */ + u32 backup_imr; /* IMR saved during suspend */ int break_active; /* break being received */ short use_dma_rx; /* enable PDC receiver */ @@ -984,8 +985,15 @@ static void atmel_serial_pm(struct uart_ * This is called on uart_open() or a resume event. */ clk_enable(atmel_port->clk); + + /* re-enable interrupts if we disabled some on suspend */ + UART_PUT_IER(port, atmel_port->backup_imr); break; case 3: + /* Back up the interrupt mask and disable all interrupts */ + atmel_port->backup_imr = UART_GET_IMR(port); + UART_PUT_IDR(port, -1); + /* * Disable the peripheral clock for this serial port. * This is called on uart_close() or a suspend event. @@ -1475,13 +1483,12 @@ static int atmel_serial_suspend(struct p cpu_relax(); } - if (device_may_wakeup(&pdev->dev) - && !atmel_serial_clk_will_stop()) - enable_irq_wake(port->irq); - else { - uart_suspend_port(&atmel_uart, port); - atmel_port->suspended = 1; - } + /* we can not wake up if we're running on slow clock */ + atmel_port->may_wakeup = device_may_wakeup(&pdev->dev); + if (atmel_serial_clk_will_stop()) + device_set_wakeup_enable(&pdev->dev, 0); + + uart_suspend_port(&atmel_uart, port); return 0; } @@ -1491,11 +1498,8 @@ static int atmel_serial_resume(struct pl struct uart_port *port = platform_get_drvdata(pdev); struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); - if (atmel_port->suspended) { - uart_resume_port(&atmel_uart, port); - atmel_port->suspended = 0; - } else - disable_irq_wake(port->irq); + uart_resume_port(&atmel_uart, port); + device_set_wakeup_enable(&pdev->dev, atmel_port->may_wakeup); return 0; } @@ -1513,6 +1517,8 @@ static int __devinit atmel_serial_probe( BUILD_BUG_ON(!is_power_of_2(ATMEL_SERIAL_RINGSIZE)); port = &atmel_ports[pdev->id]; + port->backup_imr = 0; + atmel_init_port(port, pdev); if (!atmel_use_dma_rx(&port->uart)) { _ Patches currently in -mm which might be from anti.sullin@xxxxxxxxxxxxxx are atmel_serial-update-the-powersave-handler-to-match-serial-core.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html