Re: [PATCH 02/10] atmel_serial: Fix build on avr32 with CONFIG_PM enabled

[David Brownell <david-b@pacbell.net>]

On Thursday 13 March 2008, Haavard Skinnemoen wrote:
> AVR32 doesn't have at91_suspend_entering_slow_clock(). Just assume the
> clock will keep running for now.

Well, it should acquire the clk_must_disable() or somesuch... :)

By the way, I noticed a goof in this driver's clock management.
It should leave the clock off whenever the device isn't open.
As it is, it wastes power both at runtime and during suspend.

- Dave


> Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
> ---
>  drivers/serial/atmel_serial.c |   11 ++++++++++-
>  1 files changed, 10 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
> index d57bf3e..2efbdf6 100644
> --- a/drivers/serial/atmel_serial.c
> +++ b/drivers/serial/atmel_serial.c
> @@ -1428,6 +1428,15 @@ static struct uart_driver atmel_uart = {
>  };
>  
>  #ifdef CONFIG_PM
> +static bool atmel_serial_clk_will_stop(void)
> +{
> +#ifdef CONFIG_ARCH_AT91
> +	return at91_suspend_entering_slow_clock();
> +#else
> +	return false;
> +#endif
> +}
> +
>  static int atmel_serial_suspend(struct platform_device *pdev,
>  				pm_message_t state)
>  {
> @@ -1435,7 +1444,7 @@ static int atmel_serial_suspend(struct platform_device *pdev,
>  	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
>  
>  	if (device_may_wakeup(&pdev->dev)
> -	    && !at91_suspend_entering_slow_clock())
> +	    && !atmel_serial_clk_will_stop())
>  		enable_irq_wake(port->irq);
>  	else {
>  		uart_suspend_port(&atmel_uart, port);
> -- 
> 1.5.4.3
>