[PATCH v2 14/17] drm/msm/dpu: add the writeback connector layer

[Dmitry Baryshkov]

On 20/04/2022 04:46, Abhinav Kumar wrote:
> Introduce the dpu_writeback module which serves as the
> interface between dpu operations and the drm_writeback.
> 
> This module manages the connector related operations for
> dpu writeback.
> 
> changes in v2:
> 	- start using drm_writeback_connector_init_with_encoder()
> 	- drop unnecessary arguments from dpu_writeback_init()
> 	- rebase on msm-next tip and remove usage of priv->connectors
> 
> Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
> ---
>   drivers/gpu/drm/msm/Makefile                  |  1 +
>   drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c | 68 +++++++++++++++++++++++++++
>   drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.h | 25 ++++++++++
>   3 files changed, 94 insertions(+)
>   create mode 100644 drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
>   create mode 100644 drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.h
> 
> diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile
> index 0387f22..66395ee 100644
> --- a/drivers/gpu/drm/msm/Makefile
> +++ b/drivers/gpu/drm/msm/Makefile
> @@ -80,6 +80,7 @@ msm-$(CONFIG_DRM_MSM_DPU) += \
>   	disp/dpu1/dpu_plane.o \
>   	disp/dpu1/dpu_rm.o \
>   	disp/dpu1/dpu_vbif.o \
> +	disp/dpu1/dpu_writeback.o
>   
>   msm-$(CONFIG_DRM_MSM_MDSS) += \
>   	msm_mdss.o \
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
> new file mode 100644
> index 0000000..526d884
> --- /dev/null
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c
> @@ -0,0 +1,68 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#include "dpu_writeback.h"
> +
> +static int dpu_wb_conn_get_modes(struct drm_connector *connector)
> +{
> +	struct drm_device *dev = connector->dev;
> +
> +	return drm_add_modes_noedid(connector, dev->mode_config.max_width,
> +			dev->mode_config.max_height);
> +}
> +
> +static const struct drm_connector_funcs dpu_wb_conn_funcs = {
> +	.reset = drm_atomic_helper_connector_reset,
> +	.fill_modes = drm_helper_probe_single_connector_modes,
> +	.destroy = drm_connector_cleanup,
> +	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> +	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> +};
> +
> +static int dpu_wb_conn_prepare_job(struct drm_writeback_connector *connector,
> +		struct drm_writeback_job *job)
> +{
> +	if (!job->fb)
> +		return 0;
> +
> +	dpu_encoder_prepare_wb_job(connector->encoder, job);
> +
> +	return 0;
> +}
> +
> +static void dpu_wb_conn_cleanup_job(struct drm_writeback_connector *connector,
> +		struct drm_writeback_job *job)
> +{
> +	if (!job->fb)
> +		return;
> +
> +	dpu_encoder_cleanup_wb_job(connector->encoder, job);
> +}
> +
> +static const struct drm_connector_helper_funcs dpu_wb_conn_helper_funcs = {
> +	.get_modes = dpu_wb_conn_get_modes,
> +	.prepare_writeback_job = dpu_wb_conn_prepare_job,
> +	.cleanup_writeback_job = dpu_wb_conn_cleanup_job,
> +};
> +
> +int dpu_writeback_init(struct drm_device *dev, struct drm_encoder *enc,
> +		const u32 *format_list, u32 num_formats)
> +{
> +	struct dpu_wb_connector *dpu_wb_conn;
> +	int rc = 0;
> +
> +	dpu_wb_conn = devm_kzalloc(dev->dev, sizeof(*dpu_wb_conn), GFP_KERNEL);
> +
> +	drm_connector_helper_add(&dpu_wb_conn->base.base, &dpu_wb_conn_helper_funcs);
> +
> +	/* DPU initializes the encoder and sets it up completely for writeback
> +	 * cases and hence should use the new API drm_writeback_connector_init_with_encoder
> +	 * to initialize the writeback connector
> +	 */
> +	rc = drm_writeback_connector_init_with_encoder(dev, &dpu_wb_conn->base, enc,
> +			&dpu_wb_conn_funcs, format_list, num_formats);
> +
> +	return rc;
> +}
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.h
> new file mode 100644
> index 0000000..05aff05
> --- /dev/null
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.h
> @@ -0,0 +1,25 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#ifndef _DPU_WRITEBACK_H
> +#define _DPU_WRITEBACK_H
> +
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_file.h>
> +#include <drm/drm_probe_helper.h>
> +#include <drm/drm_writeback.h>
> +
> +#include "msm_drv.h"
> +#include "dpu_kms.h"
> +#include "dpu_encoder_phys.h"
> +
> +struct dpu_wb_connector {
> +	struct drm_writeback_connector base;
> +};

Do you plan to add more fields to this struct? If not, we can probably 
drop it and use struct drm_writeback_connector directly.

> +
> +int dpu_writeback_init(struct drm_device *dev, struct drm_encoder *enc,
> +		const u32 *format_list, u32 num_formats);
> +
> +#endif /*_DPU_WRITEBACK_H */


-- 
With best wishes
Dmitry