Re: [PATCH 2/2] drm/i915: CABC support for backlight control

[Jani Nikula <jani.nikula@intel.com>]

On Thu, 24 Mar 2016, Deepak M <m.deepak@intel.com> wrote:
> [ text/plain ]
> In CABC (Content Adaptive Brightness Control) content grey level
> scale can be increased while simultaneously decreasing
> brightness of the backlight to achieve same perceived brightness.
>
> The CABC is not standardized and panel vendors are free to follow
> their implementation. The CABC implementaion here assumes that the
> panels use standard SW register for control.
>
> In this design there will be no PWM signal from the SoC and DCS
> commands are sent to enable and control the backlight brightness.
>
> v2: Moving the CABC bkl functions to new file.(Jani)
>
> v3: Rebase
>
> v4: Rebase
>
> v5: Use mipi_dsi_dcs_write() instead of mipi_dsi_dcs_write_buffer() (Jani)
>     Move DCS macro`s to include/video/mipi_display.h (Jani)

Where's the patch actually adding the macros? We need that in the same
series to have CI actually build and run this; this fails without them.

BR,
Jani.


>
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Yetunde Adebisi <yetundex.adebisi@intel.com>
> Signed-off-by: Deepak M <m.deepak@intel.com>
> ---
>
> The DCS command macro`s are defined in the patch which is posted in the
> dri-devel list.
>
>  drivers/gpu/drm/i915/Makefile         |   1 +
>  drivers/gpu/drm/i915/i915_drv.h       |   1 -
>  drivers/gpu/drm/i915/intel_drv.h      |   2 +
>  drivers/gpu/drm/i915/intel_dsi.c      |  19 ++++-
>  drivers/gpu/drm/i915/intel_dsi.h      |   4 +
>  drivers/gpu/drm/i915/intel_dsi_cabc.c | 154 ++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_panel.c    |   4 +
>  7 files changed, 182 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/intel_dsi_cabc.c
>
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index 7ffb51b..065c410 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -83,6 +83,7 @@ i915-y += dvo_ch7017.o \
>  	  intel_dp_mst.o \
>  	  intel_dp.o \
>  	  intel_dsi.o \
> +	  intel_dsi_cabc.o \
>  	  intel_dsi_panel_vbt.o \
>  	  intel_dsi_pll.o \
>  	  intel_dvo.o \
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 050d860..9ed60f8 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -3489,7 +3489,6 @@ void intel_sbi_write(struct drm_i915_private *dev_priv, u16 reg, u32 value,
>  		     enum intel_sbi_destination destination);
>  u32 vlv_flisdsi_read(struct drm_i915_private *dev_priv, u32 reg);
>  void vlv_flisdsi_write(struct drm_i915_private *dev_priv, u32 reg, u32 val);
> -
>  int intel_gpu_freq(struct drm_i915_private *dev_priv, int val);
>  int intel_freq_opcode(struct drm_i915_private *dev_priv, int val);
>  
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index c87b450..9e49396 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1325,6 +1325,8 @@ void intel_dp_mst_encoder_cleanup(struct intel_digital_port *intel_dig_port);
>  /* intel_dsi.c */
>  void intel_dsi_init(struct drm_device *dev);
>  
> +/* intel_dsi_cabc.c */
> +int intel_dsi_cabc_init_backlight_funcs(struct intel_connector *intel_connector);
>  
>  /* intel_dvo.c */
>  void intel_dvo_init(struct drm_device *dev);
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 456676c..7aa707f 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -1209,10 +1209,25 @@ void intel_dsi_init(struct drm_device *dev)
>  	else
>  		intel_encoder->crtc_mask = BIT(PIPE_B);
>  
> -	if (dev_priv->vbt.dsi.config->dual_link)
> +	if (dev_priv->vbt.dsi.config->dual_link) {
>  		intel_dsi->ports = BIT(PORT_A) | BIT(PORT_C);
> -	else
> +		switch (dev_priv->vbt.dsi.config->dl_cabc_port) {
> +		case CABC_PORT_A:
> +			intel_dsi->bkl_dcs_ports = BIT(PORT_A);
> +			break;
> +		case CABC_PORT_C:
> +			intel_dsi->bkl_dcs_ports = BIT(PORT_C);
> +			break;
> +		case CABC_PORT_A_AND_C:
> +			intel_dsi->bkl_dcs_ports = BIT(PORT_A) | BIT(PORT_C);
> +			break;
> +		default:
> +			DRM_ERROR("Unknown MIPI ports for sending DCS\n");
> +		}
> +	} else {
>  		intel_dsi->ports = BIT(port);
> +		intel_dsi->bkl_dcs_ports = BIT(port);
> +	}
>  
>  	/* Create a DSI host (and a device) for each port. */
>  	for_each_dsi_port(port, intel_dsi->ports) {
> diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
> index 0e758f1..5c07d59 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.h
> +++ b/drivers/gpu/drm/i915/intel_dsi.h
> @@ -34,6 +34,10 @@
>  #define DSI_DUAL_LINK_FRONT_BACK	1
>  #define DSI_DUAL_LINK_PIXEL_ALT		2
>  
> +#define CABC_PORT_A                     0x00
> +#define CABC_PORT_C                     0x01
> +#define CABC_PORT_A_AND_C               0x02
> +
>  struct intel_dsi_host;
>  
>  struct intel_dsi {
> diff --git a/drivers/gpu/drm/i915/intel_dsi_cabc.c b/drivers/gpu/drm/i915/intel_dsi_cabc.c
> new file mode 100644
> index 0000000..230ee4f
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/intel_dsi_cabc.c
> @@ -0,0 +1,154 @@
> +/*
> + * Copyright © 2016 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * Author: Deepak M <m.deepak at intel.com>
> + */
> +
> +#include "intel_drv.h"
> +#include "intel_dsi.h"
> +#include "i915_drv.h"
> +#include <video/mipi_display.h>
> +#include <drm/drm_mipi_dsi.h>
> +
> +#define CABC_OFF                        (0 << 0)
> +#define CABC_USER_INTERFACE_IMAGE       (1 << 0)
> +#define CABC_STILL_PICTURE              (2 << 0)
> +#define CABC_VIDEO_MODE                 (3 << 0)
> +
> +#define CABC_BACKLIGHT                  (1 << 2)
> +#define CABC_DIMMING_DISPLAY            (1 << 3)
> +#define CABC_BCTRL                      (1 << 5)
> +
> +#define CABC_MAX_VALUE                  0xFF
> +
> +static u32 cabc_get_backlight(struct intel_connector *connector)
> +{
> +	struct intel_encoder *encoder = connector->encoder;
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
> +	struct mipi_dsi_device *dsi_device;
> +	u8 data[2] = {0};
> +	enum port port;
> +
> +	for_each_dsi_port(port, intel_dsi->bkl_dcs_ports) {
> +		dsi_device = intel_dsi->dsi_hosts[port]->device;
> +		mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
> +					data, 2);
> +	}
> +
> +	return data[1];
> +}
> +
> +static void cabc_set_backlight(struct intel_connector *connector, u32 level)
> +{
> +	struct intel_encoder *encoder = connector->encoder;
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
> +	struct mipi_dsi_device *dsi_device;
> +	u8 data = 0;
> +	enum port port;
> +
> +	for_each_dsi_port(port, intel_dsi->bkl_dcs_ports) {
> +		dsi_device = intel_dsi->dsi_hosts[port]->device;
> +		data = level;
> +		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
> +					&data, sizeof(data));
> +	}
> +}
> +
> +static void cabc_disable_backlight(struct intel_connector *connector)
> +{
> +	struct intel_encoder *encoder = connector->encoder;
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
> +	struct mipi_dsi_device *dsi_device;
> +	enum port port;
> +	u8 data = 0;
> +
> +	cabc_set_backlight(connector, 0);
> +
> +	for_each_dsi_port(port, intel_dsi->bkl_dcs_ports) {
> +		dsi_device = intel_dsi->dsi_hosts[port]->device;
> +		data = CABC_OFF;
> +		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
> +					&data, sizeof(data));
> +		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
> +					&data, sizeof(data));
> +	}
> +}
> +
> +static void cabc_enable_backlight(struct intel_connector *connector)
> +{
> +	struct intel_encoder *encoder = connector->encoder;
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
> +	struct intel_panel *panel = &connector->panel;
> +	struct mipi_dsi_device *dsi_device;
> +	enum port port;
> +	u8 data = 0;
> +
> +	for_each_dsi_port(port, intel_dsi->bkl_dcs_ports) {
> +		dsi_device = intel_dsi->dsi_hosts[port]->device;
> +		data = CABC_BACKLIGHT | CABC_DIMMING_DISPLAY | CABC_BCTRL;
> +		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
> +					&data, sizeof(data));
> +		data = CABC_STILL_PICTURE;
> +		mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
> +					&data, sizeof(data));
> +	}
> +
> +	cabc_set_backlight(connector, panel->backlight.level);
> +}
> +
> +static int cabc_setup_backlight(struct intel_connector *connector,
> +		enum pipe unused)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +
> +	panel->backlight.max = CABC_MAX_VALUE;
> +	panel->backlight.level = CABC_MAX_VALUE;
> +
> +	return 0;
> +}
> +
> +int intel_dsi_cabc_init_backlight_funcs(struct intel_connector *intel_connector)
> +{
> +	struct drm_device *dev = intel_connector->base.dev;
> +	struct drm_i915_private *dev_priv = dev->dev_private;
> +	struct intel_encoder *encoder = intel_connector->encoder;
> +	struct intel_panel *panel = &intel_connector->panel;
> +
> +	if (!dev_priv->vbt.dsi.config->cabc_supported)
> +		return -ENODEV;
> +
> +	if (encoder->type != INTEL_OUTPUT_DSI) {
> +		DRM_ERROR("Use DSI encoder for CABC\n");
> +		return -EINVAL;
> +	}
> +
> +	if (WARN_ON(encoder->type != INTEL_OUTPUT_DSI))
> +		return -EINVAL;
> +
> +	panel->backlight.setup = cabc_setup_backlight;
> +	panel->backlight.enable = cabc_enable_backlight;
> +	panel->backlight.disable = cabc_disable_backlight;
> +	panel->backlight.set = cabc_set_backlight;
> +	panel->backlight.get = cabc_get_backlight;
> +
> +	return 0;
> +}
> diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
> index 8c8996f..641c38f 100644
> --- a/drivers/gpu/drm/i915/intel_panel.c
> +++ b/drivers/gpu/drm/i915/intel_panel.c
> @@ -1718,6 +1718,10 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel)
>  		container_of(panel, struct intel_connector, panel);
>  	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>  
> +	if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
> +		intel_dsi_cabc_init_backlight_funcs(connector) == 0)
> +		return;
> +
>  	if (IS_BROXTON(dev_priv)) {
>  		panel->backlight.setup = bxt_setup_backlight;
>  		panel->backlight.enable = bxt_enable_backlight;

-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx