[PATCH v4 06/11] drm: sun4i: Add RGB output

[boris.brezillon@free-electrons.com (Boris Brezillon)]

On Mon, 25 Apr 2016 15:22:47 +0200
Maxime Ripard <maxime.ripard@free-electrons.com> wrote:

> One of the A10 display pipeline possible output is an RGB interface to
> drive LCD panels directly. This is done through the first channel of the
> TCON that will output our video signals directly.
> 
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

> ---
>  drivers/gpu/drm/sun4i/Makefile     |   1 +
>  drivers/gpu/drm/sun4i/sun4i_drv.c  |  24 ++++
>  drivers/gpu/drm/sun4i/sun4i_rgb.c  | 250 +++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/sun4i/sun4i_rgb.h  |  18 +++
>  drivers/gpu/drm/sun4i/sun4i_tcon.c |  61 ++++++++-
>  drivers/gpu/drm/sun4i/sun4i_tcon.h |   2 +
>  6 files changed, 355 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/sun4i/sun4i_rgb.c
>  create mode 100644 drivers/gpu/drm/sun4i/sun4i_rgb.h
> 
> diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile
> index 6df3ef32732d..74f804b88ff5 100644
> --- a/drivers/gpu/drm/sun4i/Makefile
> +++ b/drivers/gpu/drm/sun4i/Makefile
> @@ -4,6 +4,7 @@ sun4i-drm-y += sun4i_framebuffer.o
>  sun4i-drm-y += sun4i_layer.o
>  
>  sun4i-tcon-y += sun4i_tcon.o
> +sun4i-tcon-y += sun4i_rgb.o
>  sun4i-tcon-y += sun4i_dotclock.o
>  
>  obj-$(CONFIG_DRM_SUN4I)		+= sun4i-drm.o sun4i-tcon.o
> diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
> index a081969673ac..891d434ea57f 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_drv.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
> @@ -222,6 +222,11 @@ static bool sun4i_drv_node_is_frontend(struct device_node *node)
>  				       "allwinner,sun5i-a13-display-frontend");
>  }
>  
> +static bool sun4i_drv_node_is_tcon(struct device_node *node)
> +{
> +	return of_device_is_compatible(node, "allwinner,sun5i-a13-tcon");
> +}
> +
>  static int compare_of(struct device *dev, void *data)
>  {
>  	DRM_DEBUG_DRIVER("Comparing of node %s with %s\n",
> @@ -270,6 +275,25 @@ static int sun4i_drv_add_endpoints(struct device *dev,
>  			continue;
>  		}
>  
> +		/*
> +		 * If the node is our TCON, the first port is used for our
> +		 * panel, and will not be part of the
> +		 * component framework.
> +		 */
> +		if (sun4i_drv_node_is_tcon(node)) {
> +			struct of_endpoint endpoint;
> +
> +			if (of_graph_parse_endpoint(ep, &endpoint)) {
> +				DRM_DEBUG_DRIVER("Couldn't parse endpoint\n");
> +				continue;
> +			}
> +
> +			if (!endpoint.id) {
> +				DRM_DEBUG_DRIVER("Endpoint is our panel... skipping\n");
> +				continue;
> +			}
> +		}
> +
>  		/* Walk down our tree */
>  		count += sun4i_drv_add_endpoints(dev, match, remote);
>  
> diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.c b/drivers/gpu/drm/sun4i/sun4i_rgb.c
> new file mode 100644
> index 000000000000..ab6494818050
> --- /dev/null
> +++ b/drivers/gpu/drm/sun4i/sun4i_rgb.c
> @@ -0,0 +1,250 @@
> +/*
> + * Copyright (C) 2015 Free Electrons
> + * Copyright (C) 2015 NextThing Co
> + *
> + * Maxime Ripard <maxime.ripard@free-electrons.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + */
> +
> +#include <linux/clk.h>
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_panel.h>
> +
> +#include "sun4i_drv.h"
> +#include "sun4i_tcon.h"
> +
> +struct sun4i_rgb {
> +	struct drm_connector	connector;
> +	struct drm_encoder	encoder;
> +
> +	struct sun4i_drv	*drv;
> +};
> +
> +static inline struct sun4i_rgb *
> +drm_connector_to_sun4i_rgb(struct drm_connector *connector)
> +{
> +	return container_of(connector, struct sun4i_rgb,
> +			    connector);
> +}
> +
> +static inline struct sun4i_rgb *
> +drm_encoder_to_sun4i_rgb(struct drm_encoder *encoder)
> +{
> +	return container_of(encoder, struct sun4i_rgb,
> +			    encoder);
> +}
> +
> +static int sun4i_rgb_get_modes(struct drm_connector *connector)
> +{
> +	struct sun4i_rgb *rgb =
> +		drm_connector_to_sun4i_rgb(connector);
> +	struct sun4i_drv *drv = rgb->drv;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +
> +	return drm_panel_get_modes(tcon->panel);
> +}
> +
> +static int sun4i_rgb_mode_valid(struct drm_connector *connector,
> +				struct drm_display_mode *mode)
> +{
> +	u32 hsync = mode->hsync_end - mode->hsync_start;
> +	u32 vsync = mode->vsync_end - mode->vsync_start;
> +
> +	DRM_DEBUG_DRIVER("Validating modes...\n");
> +
> +	if (hsync < 1)
> +		return MODE_HSYNC_NARROW;
> +
> +	if (hsync > 0x3ff)
> +		return MODE_HSYNC_WIDE;
> +
> +	if ((mode->hdisplay < 1) || (mode->htotal < 1))
> +		return MODE_H_ILLEGAL;
> +
> +	if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff))
> +		return MODE_BAD_HVALUE;
> +
> +	DRM_DEBUG_DRIVER("Horizontal parameters OK\n");
> +
> +	if (vsync < 1)
> +		return MODE_VSYNC_NARROW;
> +
> +	if (vsync > 0x3ff)
> +		return MODE_VSYNC_WIDE;
> +
> +	if ((mode->vdisplay < 1) || (mode->vtotal < 1))
> +		return MODE_V_ILLEGAL;
> +
> +	if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff))
> +		return MODE_BAD_VVALUE;
> +
> +	DRM_DEBUG_DRIVER("Vertical parameters OK\n");
> +
> +	return MODE_OK;
> +}
> +
> +static struct drm_encoder *
> +sun4i_rgb_best_encoder(struct drm_connector *connector)
> +{
> +	struct sun4i_rgb *rgb =
> +		drm_connector_to_sun4i_rgb(connector);
> +
> +	return &rgb->encoder;
> +}
> +
> +static struct drm_connector_helper_funcs sun4i_rgb_con_helper_funcs = {
> +	.get_modes	= sun4i_rgb_get_modes,
> +	.mode_valid	= sun4i_rgb_mode_valid,
> +	.best_encoder	= sun4i_rgb_best_encoder,
> +};
> +
> +static enum drm_connector_status
> +sun4i_rgb_connector_detect(struct drm_connector *connector, bool force)
> +{
> +	return connector_status_connected;
> +}
> +
> +static void
> +sun4i_rgb_connector_destroy(struct drm_connector *connector)
> +{
> +	struct sun4i_rgb *rgb = drm_connector_to_sun4i_rgb(connector);
> +	struct sun4i_drv *drv = rgb->drv;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +
> +	drm_panel_detach(tcon->panel);
> +	drm_connector_cleanup(connector);
> +}
> +
> +static struct drm_connector_funcs sun4i_rgb_con_funcs = {
> +	.dpms			= drm_atomic_helper_connector_dpms,
> +	.detect			= sun4i_rgb_connector_detect,
> +	.fill_modes		= drm_helper_probe_single_connector_modes,
> +	.destroy		= sun4i_rgb_connector_destroy,
> +	.reset			= drm_atomic_helper_connector_reset,
> +	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
> +	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
> +};
> +
> +static int sun4i_rgb_atomic_check(struct drm_encoder *encoder,
> +				  struct drm_crtc_state *crtc_state,
> +				  struct drm_connector_state *conn_state)
> +{
> +	return 0;
> +}
> +
> +static void sun4i_rgb_encoder_enable(struct drm_encoder *encoder)
> +{
> +	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
> +	struct sun4i_drv *drv = rgb->drv;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +
> +	DRM_DEBUG_DRIVER("Enabling RGB output\n");
> +
> +	drm_panel_enable(tcon->panel);
> +	sun4i_tcon_channel_enable(tcon, 0);
> +}
> +
> +static void sun4i_rgb_encoder_disable(struct drm_encoder *encoder)
> +{
> +	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
> +	struct sun4i_drv *drv = rgb->drv;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +
> +	DRM_DEBUG_DRIVER("Disabling RGB output\n");
> +
> +	sun4i_tcon_channel_disable(tcon, 0);
> +	drm_panel_disable(tcon->panel);
> +}
> +
> +static void sun4i_rgb_encoder_mode_set(struct drm_encoder *encoder,
> +				       struct drm_display_mode *mode,
> +				       struct drm_display_mode *adjusted_mode)
> +{
> +	struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder);
> +	struct sun4i_drv *drv = rgb->drv;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +
> +	sun4i_tcon0_mode_set(tcon, mode);
> +
> +	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
> +
> +	/* FIXME: This seems to be board specific */
> +	clk_set_phase(tcon->dclk, 120);
> +}
> +
> +static struct drm_encoder_helper_funcs sun4i_rgb_enc_helper_funcs = {
> +	.atomic_check	= sun4i_rgb_atomic_check,
> +	.mode_set	= sun4i_rgb_encoder_mode_set,
> +	.disable	= sun4i_rgb_encoder_disable,
> +	.enable		= sun4i_rgb_encoder_enable,
> +};
> +
> +static void sun4i_rgb_enc_destroy(struct drm_encoder *encoder)
> +{
> +	drm_encoder_cleanup(encoder);
> +}
> +
> +static struct drm_encoder_funcs sun4i_rgb_enc_funcs = {
> +	.destroy	= sun4i_rgb_enc_destroy,
> +};
> +
> +int sun4i_rgb_init(struct drm_device *drm)
> +{
> +	struct sun4i_drv *drv = drm->dev_private;
> +	struct sun4i_tcon *tcon = drv->tcon;
> +	struct sun4i_rgb *rgb;
> +	int ret;
> +
> +	/* If we don't have a panel, there's no point in going on */
> +	if (!tcon->panel)
> +		return -ENODEV;
> +
> +	rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL);
> +	if (!rgb)
> +		return -ENOMEM;
> +	rgb->drv = drv;
> +
> +	drm_encoder_helper_add(&rgb->encoder,
> +			       &sun4i_rgb_enc_helper_funcs);
> +	ret = drm_encoder_init(drm,
> +			       &rgb->encoder,
> +			       &sun4i_rgb_enc_funcs,
> +			       DRM_MODE_ENCODER_NONE,
> +			       NULL);
> +	if (ret) {
> +		dev_err(drm->dev, "Couldn't initialise the rgb encoder\n");
> +		goto err_out;
> +	}
> +
> +	/* The RGB encoder can only work with the TCON channel 0 */
> +	rgb->encoder.possible_crtcs = BIT(0);
> +
> +	drm_connector_helper_add(&rgb->connector,
> +				 &sun4i_rgb_con_helper_funcs);
> +	ret = drm_connector_init(drm, &rgb->connector,
> +				 &sun4i_rgb_con_funcs,
> +				 DRM_MODE_CONNECTOR_Unknown);
> +	if (ret) {
> +		dev_err(drm->dev, "Couldn't initialise the rgb connector\n");
> +		goto err_cleanup_connector;
> +	}
> +
> +	drm_mode_connector_attach_encoder(&rgb->connector, &rgb->encoder);
> +
> +	drm_panel_attach(tcon->panel, &rgb->connector);
> +
> +	return 0;
> +
> +err_cleanup_connector:
> +	drm_encoder_cleanup(&rgb->encoder);
> +err_out:
> +	return ret;
> +}
> +EXPORT_SYMBOL(sun4i_rgb_init);
> diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.h b/drivers/gpu/drm/sun4i/sun4i_rgb.h
> new file mode 100644
> index 000000000000..7c4da4c8acdd
> --- /dev/null
> +++ b/drivers/gpu/drm/sun4i/sun4i_rgb.h
> @@ -0,0 +1,18 @@
> +/*
> + * Copyright (C) 2015 Free Electrons
> + * Copyright (C) 2015 NextThing Co
> + *
> + * Maxime Ripard <maxime.ripard@free-electrons.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + */
> +
> +#ifndef _SUN4I_RGB_H_
> +#define _SUN4I_RGB_H_
> +
> +int sun4i_rgb_init(struct drm_device *drm);
> +
> +#endif /* _SUN4I_RGB_H_ */
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index 5fbd3ce9d651..9f19b0e08560 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -15,10 +15,12 @@
>  #include <drm/drm_crtc.h>
>  #include <drm/drm_crtc_helper.h>
>  #include <drm/drm_modes.h>
> +#include <drm/drm_panel.h>
>  
>  #include <linux/component.h>
>  #include <linux/ioport.h>
>  #include <linux/of_address.h>
> +#include <linux/of_graph.h>
>  #include <linux/of_irq.h>
>  #include <linux/regmap.h>
>  #include <linux/reset.h>
> @@ -26,6 +28,7 @@
>  #include "sun4i_crtc.h"
>  #include "sun4i_dotclock.h"
>  #include "sun4i_drv.h"
> +#include "sun4i_rgb.h"
>  #include "sun4i_tcon.h"
>  
>  void sun4i_tcon_disable(struct sun4i_tcon *tcon)
> @@ -395,6 +398,40 @@ static int sun4i_tcon_init_regmap(struct device *dev,
>  	return 0;
>  }
>  
> +static struct drm_panel *sun4i_tcon_find_panel(struct device_node *node)
> +{
> +	struct device_node *port, *remote, *child;
> +	struct device_node *end_node = NULL;
> +
> +	/* Inputs are listed first, then outputs */
> +	port = of_graph_get_port_by_id(node, 1);
> +
> +	/*
> +	 * Our first output is the RGB interface where the panel will
> +	 * be connected.
> +	 */
> +	for_each_child_of_node(port, child) {
> +		u32 reg;
> +
> +		of_property_read_u32(child, "reg", &reg);
> +		if (reg == 0)
> +			end_node = child;
> +	}
> +
> +	if (!end_node) {
> +		DRM_DEBUG_DRIVER("Missing panel endpoint\n");
> +		return ERR_PTR(-ENODEV);
> +	}
> +
> +	remote = of_graph_get_remote_port_parent(end_node);
> +	if (!remote) {
> +		DRM_DEBUG_DRIVER("Enable to parse remote node\n");
> +		return ERR_PTR(-EINVAL);
> +	}
> +
> +	return of_drm_find_panel(remote);
> +}
> +
>  static int sun4i_tcon_bind(struct device *dev, struct device *master,
>  			   void *data)
>  {
> @@ -447,7 +484,13 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
>  		goto err_free_clocks;
>  	}
>  
> -	return 0;
> +	tcon->panel = sun4i_tcon_find_panel(dev->of_node);
> +	if (IS_ERR(tcon->panel)) {
> +		dev_info(dev, "No panel found... RGB output disabled\n");
> +		return 0;
> +	}
> +
> +	return sun4i_rgb_init(drm);
>  
>  err_free_clocks:
>  	sun4i_tcon_free_clocks(tcon);
> @@ -471,6 +514,22 @@ static struct component_ops sun4i_tcon_ops = {
>  
>  static int sun4i_tcon_probe(struct platform_device *pdev)
>  {
> +	struct device_node *node = pdev->dev.of_node;
> +	struct drm_panel *panel;
> +
> +	/*
> +	 * The panel is not ready.
> +	 * Defer the probe.
> +	 */
> +	panel = sun4i_tcon_find_panel(node);
> +	if (IS_ERR(panel)) {
> +		/*
> +		 * If we don't have a panel endpoint, just go on
> +		 */
> +		if (PTR_ERR(panel) != -ENODEV)
> +			return -EPROBE_DEFER;
> +	}
> +
>  	return component_add(&pdev->dev, &sun4i_tcon_ops);
>  }
>  
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> index 35161218c2c1..0e0b11db401b 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> @@ -161,6 +161,8 @@ struct sun4i_tcon {
>  
>  	/* Platform adjustments */
>  	bool				has_mux;
> +
> +	struct drm_panel		*panel;
>  };
>  
>  /* Global Control */



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com