Hi Fabrizio,

Thank you for the patch.

On Thu, Nov 07, 2019 at 08:10:58PM +0000, Fabrizio Castro wrote:
> lvds-encoder.c implementation is also suitable for LVDS decoders,
> not just LVDS encoders.
> Instead of creating a new driver for addressing support for
> transparent LVDS decoders, repurpose lvds-encoder.c for the greater
> good.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.cas...@bp.renesas.com>
> 
> ---
> v2->v3:
> * No change
> v1->v2:
> * No change
> ---
>  drivers/gpu/drm/bridge/Kconfig        |   8 +-
>  drivers/gpu/drm/bridge/Makefile       |   2 +-
>  drivers/gpu/drm/bridge/lvds-codec.c   | 131 ++++++++++++++++++++++++++++
>  drivers/gpu/drm/bridge/lvds-encoder.c | 155 
> ----------------------------------
>  4 files changed, 136 insertions(+), 160 deletions(-)

It would help if you added the -M1 option to git-format-patch to detect
the rename, the result would be easier to review.

>  create mode 100644 drivers/gpu/drm/bridge/lvds-codec.c
>  delete mode 100644 drivers/gpu/drm/bridge/lvds-encoder.c
> 
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 3436297..9e75ca4e 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -45,14 +45,14 @@ config DRM_DUMB_VGA_DAC
>         Support for non-programmable RGB to VGA DAC bridges, such as ADI
>         ADV7123, TI THS8134 and THS8135 or passive resistor ladder DACs.
>  
> -config DRM_LVDS_ENCODER
> -     tristate "Transparent parallel to LVDS encoder support"
> +config DRM_LVDS_CODEC
> +     tristate "Transparent LVDS encoders and decoders support"
>       depends on OF
>       select DRM_KMS_HELPER
>       select DRM_PANEL_BRIDGE
>       help
> -       Support for transparent parallel to LVDS encoders that don't require
> -       any configuration.
> +       Support for transparent LVDS encoders and LVDS decoders that don't
> +       require any configuration.
>  
>  config DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW
>       tristate "MegaChips stdp4028-ge-b850v3-fw and stdp2690-ge-b850v3-fw"
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index 4934fcf..8a9178a 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -2,7 +2,7 @@
>  obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o
>  obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
>  obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o
> -obj-$(CONFIG_DRM_LVDS_ENCODER) += lvds-encoder.o
> +obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
>  obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += 
> megachips-stdpxxxx-ge-b850v3-fw.o
>  obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
>  obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
> diff --git a/drivers/gpu/drm/bridge/lvds-codec.c 
> b/drivers/gpu/drm/bridge/lvds-codec.c
> new file mode 100644
> index 0000000..d57a8eb
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/lvds-codec.c
> @@ -0,0 +1,131 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2019 Renesas Electronics Corporation
> + * Copyright (C) 2016 Laurent Pinchart <laurent.pinch...@ideasonboard.com>
> + */
> +
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +
> +#include <drm/drm_bridge.h>
> +#include <drm/drm_panel.h>
> +
> +struct lvds_codec {
> +     struct drm_bridge bridge;
> +     struct drm_bridge *panel_bridge;
> +     struct gpio_desc *powerdown_gpio;
> +};
> +
> +static int lvds_codec_attach(struct drm_bridge *bridge)
> +{
> +     struct lvds_codec *lvds_codec = container_of(bridge,
> +                                                  struct lvds_codec, bridge);
> +
> +     return drm_bridge_attach(bridge->encoder, lvds_codec->panel_bridge,
> +                              bridge);
> +}
> +
> +static void lvds_codec_enable(struct drm_bridge *bridge)
> +{
> +     struct lvds_codec *lvds_codec = container_of(bridge,
> +                                                  struct lvds_codec, bridge);
> +
> +     if (lvds_codec->powerdown_gpio)
> +             gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 0);
> +}
> +
> +static void lvds_codec_disable(struct drm_bridge *bridge)
> +{
> +     struct lvds_codec *lvds_codec = container_of(bridge,
> +                                                  struct lvds_codec, bridge);
> +
> +     if (lvds_codec->powerdown_gpio)
> +             gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 1);
> +}
> +
> +static struct drm_bridge_funcs funcs = {
> +     .attach = lvds_codec_attach,
> +     .enable = lvds_codec_enable,
> +     .disable = lvds_codec_disable,
> +};
> +
> +static int lvds_codec_probe(struct platform_device *pdev)
> +{
> +     struct device *dev = &pdev->dev;
> +     struct device_node *panel_node;
> +     struct drm_panel *panel;
> +     struct lvds_codec *lvds_codec;
> +
> +     lvds_codec = devm_kzalloc(dev, sizeof(*lvds_codec), GFP_KERNEL);
> +     if (!lvds_codec)
> +             return -ENOMEM;
> +
> +     lvds_codec->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown",
> +                                                          GPIOD_OUT_HIGH);
> +     if (IS_ERR(lvds_codec->powerdown_gpio))
> +             return PTR_ERR(lvds_codec->powerdown_gpio);

The driver had an error message here, any reason it got removed ?

> +
> +     panel_node = of_graph_get_remote_node(dev->of_node, 1, 0);
> +     if (!panel_node) {
> +             dev_dbg(dev, "panel DT node not found\n");
> +             return -ENXIO;
> +     }
> +
> +     panel = of_drm_find_panel(panel_node);
> +     of_node_put(panel_node);
> +     if (IS_ERR(panel)) {
> +             dev_dbg(dev, "panel not found, deferring probe\n");
> +             return PTR_ERR(panel);
> +     }
> +
> +     lvds_codec->panel_bridge = devm_drm_panel_bridge_add(dev, panel);

This was devm_drm_panel_bridge_add_typed(), do you think there's a risk
of breaking userspace ? Of course as noted in the documentation of
devm_drm_panel_bridge_add_typed() the right solution is to fix panel
drivers, but I'm still slightly worried.

Actually, could you split this patch in two, with a patch that only
renames the driver (and the symbols internally) without any functional
change, and another patch that performs the modifications ? That would
be much easier to review and discuss.

> +     if (IS_ERR(lvds_codec->panel_bridge))
> +             return PTR_ERR(lvds_codec->panel_bridge);
> +
> +     /* The panel_bridge bridge is attached to the panel's of_node,
> +      * but we need a bridge attached to our of_node for our user
> +      * to look up.
> +      */
> +     lvds_codec->bridge.of_node = dev->of_node;
> +     lvds_codec->bridge.funcs = &funcs;
> +     drm_bridge_add(&lvds_codec->bridge);
> +
> +     platform_set_drvdata(pdev, lvds_codec);
> +
> +     return 0;
> +}
> +
> +static int lvds_codec_remove(struct platform_device *pdev)
> +{
> +     struct lvds_codec *lvds_codec = platform_get_drvdata(pdev);
> +
> +     drm_bridge_remove(&lvds_codec->bridge);
> +
> +     return 0;
> +}
> +
> +static const struct of_device_id lvds_codec_match[] = {
> +     { .compatible = "lvds-encoder"  },
> +     { .compatible = "thine,thc63lvdm83d" },
> +     { .compatible = "lvds-decoder" },
> +     {},
> +};
> +MODULE_DEVICE_TABLE(of, lvds_codec_match);
> +
> +static struct platform_driver lvds_codec_driver = {
> +     .probe  = lvds_codec_probe,
> +     .remove = lvds_codec_remove,
> +     .driver         = {
> +             .name           = "lvds-codec",
> +             .of_match_table = lvds_codec_match,
> +     },
> +};
> +module_platform_driver(lvds_codec_driver);
> +
> +MODULE_AUTHOR("Laurent Pinchart <laurent.pinch...@ideasonboard.com>");
> +MODULE_DESCRIPTION("Driver for transparent LVDS encoders and LVDS decoders");

Maybe "LVDS encoders and decoders" ?

> +MODULE_LICENSE("GPL");

[snip]

-- 
Regards,

Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to