Re: [PATCH v3 1/2] DRM: ARC: add HDMI 2.0 TX encoder support
From: Daniel Vetter
Date: Wed Apr 15 2020 - 13:34:20 EST
On Wed, Apr 15, 2020 at 02:29:28AM +0300, Eugeniy Paltsev wrote:
> The Synopsys ARC SoCs (like HSDK4xD) include on-chip DesignWare HDMI
> encoders. Support them with a platform driver to provide platform glue
> data to the dw-hdmi driver.
>
> Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
> ---
> MAINTAINERS | 6 ++
> drivers/gpu/drm/Makefile | 2 +-
> drivers/gpu/drm/arc/Kconfig | 7 ++
> drivers/gpu/drm/arc/Makefile | 1 +
> drivers/gpu/drm/arc/arc-dw-hdmi.c | 116 ++++++++++++++++++++++++++++++
> 5 files changed, 131 insertions(+), 1 deletion(-)
> create mode 100644 drivers/gpu/drm/arc/arc-dw-hdmi.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a6fbdf354d34..2aaed1190370 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1258,6 +1258,12 @@ S: Supported
> F: drivers/gpu/drm/arc/
> F: Documentation/devicetree/bindings/display/snps,arcpgu.txt
>
> +ARC DW HDMI DRIVER
> +M: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
> +S: Supported
> +F: drivers/gpu/drm/arc/arc-dw-hdmi.c
> +F: Documentation/devicetree/bindings/display/bridge/snps,arc-dw-hdmi.yaml
> +
> ARCNET NETWORK LAYER
> M: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>
> L: netdev@xxxxxxxxxxxxxxx
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index 6493088a0fdd..5b0bcf7f45cd 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -109,7 +109,7 @@ obj-y += panel/
> obj-y += bridge/
> obj-$(CONFIG_DRM_FSL_DCU) += fsl-dcu/
> obj-$(CONFIG_DRM_ETNAVIV) += etnaviv/
> -obj-$(CONFIG_DRM_ARCPGU)+= arc/
> +obj-y += arc/
> obj-y += hisilicon/
> obj-$(CONFIG_DRM_ZTE) += zte/
> obj-$(CONFIG_DRM_MXSFB) += mxsfb/
> diff --git a/drivers/gpu/drm/arc/Kconfig b/drivers/gpu/drm/arc/Kconfig
> index e8f3d63e0b91..baec9d2a4fba 100644
> --- a/drivers/gpu/drm/arc/Kconfig
> +++ b/drivers/gpu/drm/arc/Kconfig
> @@ -8,3 +8,10 @@ config DRM_ARCPGU
> Choose this option if you have an ARC PGU controller.
>
> If M is selected the module will be called arcpgu.
> +
> +config DRM_ARC_DW_HDMI
> + tristate "ARC DW HDMI"
> + depends on DRM && OF
> + select DRM_DW_HDMI
> + help
> + Synopsys DW HDMI driver for various ARC development boards
> diff --git a/drivers/gpu/drm/arc/Makefile b/drivers/gpu/drm/arc/Makefile
> index c7028b7427b3..7a156d8c2c3c 100644
> --- a/drivers/gpu/drm/arc/Makefile
> +++ b/drivers/gpu/drm/arc/Makefile
> @@ -1,3 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0-only
> arcpgu-y := arcpgu_crtc.o arcpgu_hdmi.o arcpgu_sim.o arcpgu_drv.o
> obj-$(CONFIG_DRM_ARCPGU) += arcpgu.o
> +obj-$(CONFIG_DRM_ARC_DW_HDMI) += arc-dw-hdmi.o
> diff --git a/drivers/gpu/drm/arc/arc-dw-hdmi.c b/drivers/gpu/drm/arc/arc-dw-hdmi.c
> new file mode 100644
> index 000000000000..46a6ee09b302
> --- /dev/null
> +++ b/drivers/gpu/drm/arc/arc-dw-hdmi.c
> @@ -0,0 +1,116 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +//
> +// Synopsys DW HDMI driver for various ARC development boards
> +//
> +// Copyright (C) 2020 Synopsys
> +// Author: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
> +
> +#include <linux/component.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <drm/bridge/dw_hdmi.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_edid.h>
> +#include <drm/drm_encoder_slave.h>
> +#include <drm/drm_of.h>
> +
> +static const struct dw_hdmi_mpll_config snps_hdmi_mpll_cfg[] = {
> + {
> + 27000000, {
> + { 0x00B3, 0x0000 },
> + { 0x00B3, 0x0000 },
> + { 0x00B3, 0x0000 }
> + },
> + }, {
> + 74250000, {
> + { 0x0072, 0x0001},
> + { 0x0072, 0x0001},
> + { 0x0072, 0x0001}
> + },
> + }, {
> + 148500000, {
> + { 0x0051, 0x0002},
> + { 0x0051, 0x0002},
> + { 0x0051, 0x0002}
> + },
> + }, {
> + ~0UL, {
> + { 0x00B3, 0x0000 },
> + { 0x00B3, 0x0000 },
> + { 0x00B3, 0x0000 },
> + },
> + }
> +};
> +
> +static const struct dw_hdmi_curr_ctrl snps_hdmi_cur_ctr[] = {
> + /* pixelclk bpp8 bpp10 bpp12 */
> + { 27000000, { 0x0000, 0x0000, 0x0000 }, },
> + { 74250000, { 0x0008, 0x0008, 0x0008 }, },
> + { 148500000, { 0x001b, 0x001b, 0x001b }, },
> + { ~0UL, { 0x0000, 0x0000, 0x0000 }, }
> +};
> +
> +
> +static const struct dw_hdmi_phy_config snps_hdmi_phy_config[] = {
> + /* pixelclk symbol term vlev */
> + { 27000000, 0x8009, 0x0004, 0x0232},
> + { 74250000, 0x8009, 0x0004, 0x0232},
> + { 148500000, 0x8009, 0x0004, 0x0232},
> + { ~0UL, 0x8009, 0x0004, 0x0232}
> +};
> +
> +static struct dw_hdmi_plat_data snps_dw_hdmi_drv_data = {
> + .mpll_cfg = snps_hdmi_mpll_cfg,
> + .cur_ctr = snps_hdmi_cur_ctr,
> + .phy_config = snps_hdmi_phy_config,
> +};
> +
> +static const struct of_device_id snps_dw_hdmi_dt_ids[] = {
> + { .compatible = "snps,arc-dw-hdmi-hsdk", .data = &snps_dw_hdmi_drv_data },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, snps_dw_hdmi_dt_ids);
> +
> +static int snps_dw_hdmi_probe(struct platform_device *pdev)
> +{
> + const struct dw_hdmi_plat_data *plat_data;
> + const struct of_device_id *match;
> + struct dw_hdmi *hdmi;
> +
> + if (!pdev->dev.of_node)
> + return -ENODEV;
> +
> + match = of_match_node(snps_dw_hdmi_dt_ids, pdev->dev.of_node);
> + plat_data = match->data;
> +
> + hdmi = dw_hdmi_probe(pdev, plat_data);
So this is kinda not how bridge drivers are supposed to be done nowadays,
direct calling into the driver was the old way, and dw-hdmi still works
like that. Modern way is roughly
- bridge drivers bind automatically to any bridge they support
- bridge drivers publish a bridge with drm_bridge_add()
- the driver using the bridge fishes out with dt magic using
of_drm_find_bridge() or another of the related of_ functions
I know a bit late, just spotted this because you brought your series here
up in my arc cleanup series, but can you pls look into adjusting
accordingly?
I shouldn't take more than moving this binding here into the dw-hdmi
driver, and switching arc itself over to the of_drm_find_bridge() call.
That way we could slowly work to transform old bridge drivers like dw-hdmi
to the new way, instead of adding more cases that will never get
converted.
Other upside is that arc stays a neat&tiny driver :-)
Thanks, Daniel
> + if (IS_ERR(hdmi))
> + return PTR_ERR(hdmi);
> +
> + platform_set_drvdata(pdev, hdmi);
> +
> + return 0;
> +}
> +
> +static int snps_dw_hdmi_remove(struct platform_device *pdev)
> +{
> + struct dw_hdmi *hdmi = platform_get_drvdata(pdev);
> +
> + dw_hdmi_remove(hdmi);
> +
> + return 0;
> +}
> +
> +static struct platform_driver snps_dw_hdmi_platform_driver = {
> + .probe = snps_dw_hdmi_probe,
> + .remove = snps_dw_hdmi_remove,
> + .driver = {
> + .name = KBUILD_MODNAME,
> + .of_match_table = snps_dw_hdmi_dt_ids,
> + },
> +};
> +module_platform_driver(snps_dw_hdmi_platform_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("ARC specific DW-HDMI driver extension");
> +MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>");
> --
> 2.21.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch