[v6,02/10] drm: add helper functions to retrieve old and new crtc

Add new helper functions, drm_atomic_get_old_crtc_for_encoder
and drm_atomic_get_new_crtc_for_encoder to retrieve the
corresponding crtc for the encoder.

Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
Signed-off-by: Vinod Polimera <quic_vpolimer@quicinc.com>
---
 drivers/gpu/drm/drm_atomic.c | 60 ++++++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_atomic.h     |  7 ++++++
 2 files changed, 67 insertions(+)

Gentle reminder to review this patch.

Thanks,
Vinod P.

> -----Original Message-----
> From: Vinod Polimera <quic_vpolimer@quicinc.com>
> Sent: Monday, July 11, 2022 6:27 PM
> To: dri-devel@lists.freedesktop.org; linux-arm-msm@vger.kernel.org;
> freedreno@lists.freedesktop.org; devicetree@vger.kernel.org
> Cc: Vinod Polimera (QUIC) <quic_vpolimer@quicinc.com>; linux-
> kernel@vger.kernel.org; robdclark@gmail.com; dianders@chromium.org;
> swboyd@chromium.org; Kalyan Thota (QUIC) <quic_kalyant@quicinc.com>;
> dmitry.baryshkov@linaro.org; Kuogee Hsieh (QUIC)
> <quic_khsieh@quicinc.com>; Vishnuvardhan Prodduturi (QUIC)
> <quic_vproddut@quicinc.com>; bjorn.andersson@linaro.org; Aravind
> Venkateswaran (QUIC) <quic_aravindh@quicinc.com>; Abhinav Kumar
> (QUIC) <quic_abhinavk@quicinc.com>; Sankeerth Billakanti (QUIC)
> <quic_sbillaka@quicinc.com>
> Subject: [PATCH v6 02/10] drm: add helper functions to retrieve old and new
> crtc
> 
> Add new helper functions, drm_atomic_get_old_crtc_for_encoder
> and drm_atomic_get_new_crtc_for_encoder to retrieve the
> corresponding crtc for the encoder.
> 
> Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
> Signed-off-by: Vinod Polimera <quic_vpolimer@quicinc.com>
> ---
>  drivers/gpu/drm/drm_atomic.c | 60
> ++++++++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_atomic.h     |  7 ++++++
>  2 files changed, 67 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 58c0283..87fcb55 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -983,6 +983,66 @@
> drm_atomic_get_new_connector_for_encoder(struct drm_atomic_state
> *state,
>  EXPORT_SYMBOL(drm_atomic_get_new_connector_for_encoder);
> 
>  /**
> + * drm_atomic_get_old_crtc_for_encoder - Get old crtc for an encoder
> + * @state: Atomic state
> + * @encoder: The encoder to fetch the crtc state for
> + *
> + * This function finds and returns the crtc that was connected to @encoder
> + * as specified by the @state.
> + *
> + * Returns: The old crtc connected to @encoder, or NULL if the encoder is
> + * not connected.
> + */
> +struct drm_crtc *
> +drm_atomic_get_old_crtc_for_encoder(struct drm_atomic_state *state,
> +				    struct drm_encoder *encoder)
> +{
> +	struct drm_connector *connector;
> +	struct drm_connector_state *conn_state;
> +
> +	connector = drm_atomic_get_old_connector_for_encoder(state,
> encoder);
> +	if (!connector)
> +		return NULL;
> +
> +	conn_state = drm_atomic_get_old_connector_state(state,
> connector);
> +	if (!conn_state)
> +		return NULL;
> +
> +	return conn_state->crtc;
> +}
> +EXPORT_SYMBOL(drm_atomic_get_old_crtc_for_encoder);
> +
> +/**
> + * drm_atomic_get_new_crtc_for_encoder - Get new crtc for an encoder
> + * @state: Atomic state
> + * @encoder: The encoder to fetch the crtc state for
> + *
> + * This function finds and returns the crtc that will be connected to
> @encoder
> + * as specified by the @state.
> + *
> + * Returns: The new crtc connected to @encoder, or NULL if the encoder is
> + * not connected.
> + */
> +struct drm_crtc *
> +drm_atomic_get_new_crtc_for_encoder(struct drm_atomic_state *state,
> +				    struct drm_encoder *encoder)
> +{
> +	struct drm_connector *connector;
> +	struct drm_connector_state *conn_state;
> +
> +	connector = drm_atomic_get_new_connector_for_encoder(state,
> encoder);
> +	if (!connector)
> +		return NULL;
> +
> +	conn_state = drm_atomic_get_new_connector_state(state,
> connector);
> +	if (!conn_state)
> +		return NULL;
> +
> +	return conn_state->crtc;
> +}
> +EXPORT_SYMBOL(drm_atomic_get_new_crtc_for_encoder);
> +
> +/**
>   * drm_atomic_get_connector_state - get connector state
>   * @state: global atomic state object
>   * @connector: connector to get state object for
> diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
> index 0777725..7001f12 100644
> --- a/include/drm/drm_atomic.h
> +++ b/include/drm/drm_atomic.h
> @@ -528,6 +528,13 @@ struct drm_connector *
>  drm_atomic_get_new_connector_for_encoder(struct drm_atomic_state
> *state,
>  					 struct drm_encoder *encoder);
> 
> +struct drm_crtc *
> +drm_atomic_get_old_crtc_for_encoder(struct drm_atomic_state *state,
> +					 struct drm_encoder *encoder);
> +struct drm_crtc *
> +drm_atomic_get_new_crtc_for_encoder(struct drm_atomic_state *state,
> +					 struct drm_encoder *encoder);
> +
>  /**
>   * drm_atomic_get_existing_crtc_state - get CRTC state, if it exists
>   * @state: global atomic state object
> --
> 2.7.4

Hi,

On Mon, Jul 11, 2022 at 5:57 AM Vinod Polimera
<quic_vpolimer@quicinc.com> wrote:
>
> Add new helper functions, drm_atomic_get_old_crtc_for_encoder
> and drm_atomic_get_new_crtc_for_encoder to retrieve the
> corresponding crtc for the encoder.
>
> Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
> Signed-off-by: Vinod Polimera <quic_vpolimer@quicinc.com>
> ---
>  drivers/gpu/drm/drm_atomic.c | 60 ++++++++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_atomic.h     |  7 ++++++
>  2 files changed, 67 insertions(+)

I don't have a lot of intuition about the code here since I haven't
messed much at this level, but what you have here looks right and
matches other similar helpers. I'm happy enough with:

Reviewed-by: Douglas Anderson <dianders@chromium.org>