[PATCH 1/4] gpu: ipu-v3: pre: add double buffer status readback

[Philipp Zabel]

Hi Lucas,

On Fri, 2018-09-14 at 18:59 +0200, Lucas Stach wrote:
> This allows the upper layers to check if a double buffer update has
> been applied by the PRE or is still pending.
> 
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> ---
>  drivers/gpu/ipu-v3/ipu-pre.c | 6 ++++++
>  drivers/gpu/ipu-v3/ipu-prv.h | 1 +
>  2 files changed, 7 insertions(+)
> 
> diff --git a/drivers/gpu/ipu-v3/ipu-pre.c b/drivers/gpu/ipu-v3/ipu-pre.c
> index 2f8db9d62551..7389ad157fd6 100644
> --- a/drivers/gpu/ipu-v3/ipu-pre.c
> +++ b/drivers/gpu/ipu-v3/ipu-pre.c
> @@ -259,6 +259,12 @@ void ipu_pre_update(struct ipu_pre *pre, unsigned int bufaddr)
>  	writel(IPU_PRE_CTRL_SDW_UPDATE, pre->regs + IPU_PRE_CTRL_SET);
>  }
>  
> +bool ipu_pre_update_done(struct ipu_pre *pre)

Nitpick, can we invert the return value and call this
ipu_pre_update_pending? That way we don't return
update_done == true if no update has been issued at all.
The same goes for patches 2 and 3.

regards
Philipp