On 09.03.2018 14:51, Jacopo Mondi wrote:
> Add transparent LVDS decoder driver.
>
> A transparent LVDS decoder is a DRM bridge device that does not require
> any configuration and converts LVDS input to digital CMOS/TTL parallel
> data output.

Neither code, neither bindings are LVDS specific, this is driver for any
bridge w/o configuration.
I  am not sure how many bridges does not need configuration, usually
they need to be powered at least.
I guess in many cases power line is always on, but this is board
specific not device specific.

Looking at previous version of the patchset it looks little bit as a
hack, and certainly it will be a hack in case of R-Car Gen3 V3M Eagle,
which I guess you want to use it.

> Signed-off-by: Jacopo Mondi <jacopo+rene...@jmondi.org>
> ---
>  drivers/gpu/drm/bridge/Kconfig        |   8 +++
>  drivers/gpu/drm/bridge/Makefile       |   1 +
>  drivers/gpu/drm/bridge/lvds-decoder.c | 129 
> ++++++++++++++++++++++++++++++++++
>  3 files changed, 138 insertions(+)
>  create mode 100644 drivers/gpu/drm/bridge/lvds-decoder.c
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 3b99d5a..e52a5af 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -32,6 +32,14 @@ config DRM_DUMB_VGA_DAC
>       help
>         Support for RGB to VGA DAC based bridges
>
> +config DRM_LVDS_DECODER
> +     tristate "Transparent LVDS to parallel decoder support"
> +     depends on OF
> +     select DRM_PANEL_BRIDGE
> +     help
> +       Support for transparent LVDS to parallel decoders that don't require
> +       any configuration.
> +
>  config DRM_LVDS_ENCODER
>       tristate "Transparent parallel to LVDS encoder support"
>       depends on OF
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index 373eb28..edc2332 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0
>  obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o
>  obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o
> +obj-$(CONFIG_DRM_LVDS_DECODER) += lvds-decoder.o
>  obj-$(CONFIG_DRM_LVDS_ENCODER) += lvds-encoder.o
>  obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += 
> megachips-stdpxxxx-ge-b850v3-fw.o
>  obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
> diff --git a/drivers/gpu/drm/bridge/lvds-decoder.c 
> b/drivers/gpu/drm/bridge/lvds-decoder.c
> new file mode 100644
> index 0000000..319f4d5
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/lvds-decoder.c
> @@ -0,0 +1,129 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * LVDS to parallel data DRM bridge driver.
> + *
> + * Copyright (C) 2018 Jacopo Mondi <jacopo+rene...@jmondi.org>
> + */
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_bridge.h>
> +#include <drm/drm_panel.h>
> +
> +#include <linux/of_graph.h>
> +
> +struct lvds_decoder {
> +     struct device *dev;
> +
> +     struct drm_bridge bridge;
> +     struct drm_bridge *next;
> +     struct drm_encoder *bridge_encoder;

Unused field.


Regards
Andrzej

> +};
> +
> +static inline struct lvds_decoder *to_lvds_decoder(struct drm_bridge *bridge)
> +{
> +     return container_of(bridge, struct lvds_decoder, bridge);
> +}
> +
> +static int lvds_decoder_attach(struct drm_bridge *bridge)
> +{
> +     struct lvds_decoder *lvds = to_lvds_decoder(bridge);
> +
> +     return drm_bridge_attach(bridge->encoder, lvds->next, bridge);
> +}
> +
> +struct drm_bridge_funcs lvds_dec_bridge_func = {
> +     .attach = lvds_decoder_attach,
> +};
> +
> +static int lvds_decoder_parse_dt(struct lvds_decoder *lvds)
> +{
> +     struct device_node *lvds_output;
> +     struct device_node *remote;
> +     int ret = 0;
> +
> +     lvds_output = of_graph_get_endpoint_by_regs(lvds->dev->of_node, 1, -1);
> +     if (!lvds_output) {
> +             dev_err(lvds->dev, "Missing endpoint in Port@1\n");
> +             return -ENODEV;
> +     }
> +
> +     remote = of_graph_get_remote_port_parent(lvds_output);
> +     if (!remote) {
> +             dev_err(lvds->dev, "Endpoint in Port@1 unconnected\n");
> +             ret = -ENODEV;
> +             goto error_put_lvds_node;
> +     }
> +
> +     if (!of_device_is_available(remote)) {
> +             dev_err(lvds->dev, "Port@1 remote endpoint is disabled\n");
> +             ret = -ENODEV;
> +             goto error_put_remote_node;
> +     }
> +
> +     lvds->next = of_drm_find_bridge(remote);
> +     if (!lvds->next)
> +             ret = -EPROBE_DEFER;
> +
> +error_put_remote_node:
> +     of_node_put(remote);
> +error_put_lvds_node:
> +     of_node_put(lvds_output);
> +
> +     return ret;
> +}
> +
> +static int lvds_decoder_probe(struct platform_device *pdev)
> +{
> +     struct lvds_decoder *lvds;
> +     int ret;
> +
> +     lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
> +     if (!lvds)
> +             return -ENOMEM;
> +
> +     lvds->dev = &pdev->dev;
> +     platform_set_drvdata(pdev, lvds);
> +
> +     ret = lvds_decoder_parse_dt(lvds);
> +     if (ret)
> +             return ret;
> +
> +     lvds->bridge.driver_private = lvds;
> +     lvds->bridge.of_node = pdev->dev.of_node;
> +     lvds->bridge.funcs = &lvds_dec_bridge_func;
> +
> +     drm_bridge_add(&lvds->bridge);
> +
> +     return 0;
> +}
> +
> +static int lvds_decoder_remove(struct platform_device *pdev)
> +{
> +     struct lvds_decoder *lvds = platform_get_drvdata(pdev);
> +
> +     drm_bridge_remove(&lvds->bridge);
> +
> +     return 0;
> +}
> +
> +#ifdef CONFIG_OF
> +static const struct of_device_id lvds_decoder_match[] = {
> +     { .compatible = "lvds-decoder", },
> +     { },
> +};
> +MODULE_DEVICE_TABLE(of, lvds_decoder_match);
> +#endif
> +
> +static struct platform_driver lvds_decoder_driver = {
> +     .probe  = lvds_decoder_probe,
> +     .remove = lvds_decoder_remove,
> +     .driver = {
> +             .name           = "lvds_decoder",
> +             .of_match_table = lvds_decoder_match,
> +     },
> +};
> +module_platform_driver(lvds_decoder_driver);
> +
> +MODULE_AUTHOR("Jacopo Mondi <jac...@jmondi.org>");
> +MODULE_DESCRIPTION("Transparent LVDS to parallel data decoder");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4
>
>
>
>

Reply via email to