Re: [PATCH 03/27] OMAP: DSS2: Reset LANEx_ULPS_SIG2 bits after use

[Archit Taneja <archit@ti.com>]

Hi,

On Friday 03 June 2011 03:30 PM, Valkeinen, Tomi wrote:
> LANEx_ULPS_SIG2 bits are left on after entering ULPS. This doesn't cause
> any problems currently, as DSI HW is reset when it is enabled. However,
> if the reset is not done, operation fails if the bits are still set.
>
> So reset the bits after entering ULPS to ensure operation even without
> HW reset.
>
> Signed-off-by: Tomi Valkeinen<tomi.valkeinen@ti.com>
> ---
>   drivers/video/omap2/dss/dsi.c |    4 ++++
>   1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c
> index 69c2d4f..4496d09 100644
> --- a/drivers/video/omap2/dss/dsi.c
> +++ b/drivers/video/omap2/dss/dsi.c
> @@ -3395,6 +3395,10 @@ static int dsi_enter_ulps(struct platform_device *dsidev)
>   	dsi_unregister_isr_cio(dsidev, dsi_completion_handler,&completion,
>   			DSI_CIO_IRQ_ULPSACTIVENOT_ALL0);
>
> +	/* Reset LANEx_ULPS_SIG2 */
> +	REG_FLD_MOD(dsidev, DSI_COMPLEXIO_CFG2, (0<<  0) | (0<<  1) | (0<<  2),
> +		7, 5);
> +

We may need to reset more lanes based on the number of lanes the panel 
is using. We could calculate a mask here instead.

Archit
>   	dsi_cio_power(dsidev, DSI_COMPLEXIO_POWER_ULPS);
>
>   	dsi_if_enable(dsidev, false);