[PATCH 3/6] spi/pl022: disable the PL022 block when unused
Viresh Kumar
viresh.kumar at st.com
Wed Nov 9 05:53:24 EST 2011
On 11/9/2011 4:09 PM, Linus WALLEIJ wrote:
> From: Virupax Sadashivpetimath <virupax.sadashivpetimath at stericsson.com>
>
> Make sure we clear the enable bit when the block is not used.
> This will save some energy in certain hardware versions.
>
> Signed-off-by: Virupax Sadashivpetimath <virupax.sadashivpetimath at stericsson.com>
> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
> ---
> drivers/spi/spi-pl022.c | 5 +++++
> 1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
> index 305f2ba..fa3eaae 100644
> --- a/drivers/spi/spi-pl022.c
> +++ b/drivers/spi/spi-pl022.c
> @@ -512,6 +512,11 @@ static void giveback(struct pl022 *pl022)
> msg->state = NULL;
> if (msg->complete)
> msg->complete(msg->context);
> +
> + /* disable the SPI/SSP operation */
> + writew((readw(SSP_CR1(pl022->virtbase)) &
> + (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
> +
> /* This message is completed, so let's turn off the clocks & power */
> pm_runtime_put(&pl022->adev->dev);
> }
Reviewed-by: Viresh Kumar <viresh.kumar at st.com>
--
viresh
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