linux/drivers/gpu/drm/i915/intel_dsi_dcs_backlight.c
Deepak M 1ecc1c6cb7 drm/i915/dsi: CABC support for Panel PWM backlight control
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.

CABC is supported only when the PWM source for backlight is
from the panel.

v2 by Jani: rebase, renames, check cabc support earlier, etc.

Signed-off-by: Deepak M <m.deepak@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/883faade74d2e598b143221ccc7df6daf4393a13.1461676337.git.jani.nikula@intel.com
2016-05-17 16:12:39 +03:00

180 lines
5.5 KiB
C

/*
* 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 CONTROL_DISPLAY_BCTRL (1 << 5)
#define CONTROL_DISPLAY_DD (1 << 3)
#define CONTROL_DISPLAY_BL (1 << 2)
#define POWER_SAVE_OFF (0 << 0)
#define POWER_SAVE_LOW (1 << 0)
#define POWER_SAVE_MEDIUM (2 << 0)
#define POWER_SAVE_HIGH (3 << 0)
#define POWER_SAVE_OUTDOOR_MODE (4 << 0)
#define PANEL_PWM_MAX_VALUE 0xFF
static u32 dcs_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;
enum port port;
/* FIXME: Need to take care of 16 bit brightness level */
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
&data, sizeof(data));
break;
}
return data;
}
static void dcs_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 = level;
enum port port;
/* FIXME: Need to take care of 16 bit brightness level */
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
&data, sizeof(data));
}
}
static void dcs_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;
dcs_set_backlight(connector, 0);
for_each_dsi_port(port, intel_dsi->dcs_cabc_ports) {
u8 cabc = POWER_SAVE_OFF;
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
&cabc, sizeof(cabc));
}
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
u8 ctrl = 0;
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_CONTROL_DISPLAY,
&ctrl, sizeof(ctrl));
ctrl &= ~CONTROL_DISPLAY_BL;
ctrl &= ~CONTROL_DISPLAY_DD;
ctrl &= ~CONTROL_DISPLAY_BCTRL;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
&ctrl, sizeof(ctrl));
}
}
static void dcs_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;
for_each_dsi_port(port, intel_dsi->dcs_backlight_ports) {
u8 ctrl = 0;
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_read(dsi_device, MIPI_DCS_GET_CONTROL_DISPLAY,
&ctrl, sizeof(ctrl));
ctrl |= CONTROL_DISPLAY_BL;
ctrl |= CONTROL_DISPLAY_DD;
ctrl |= CONTROL_DISPLAY_BCTRL;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_CONTROL_DISPLAY,
&ctrl, sizeof(ctrl));
}
for_each_dsi_port(port, intel_dsi->dcs_cabc_ports) {
u8 cabc = POWER_SAVE_MEDIUM;
dsi_device = intel_dsi->dsi_hosts[port]->device;
mipi_dsi_dcs_write(dsi_device, MIPI_DCS_WRITE_POWER_SAVE,
&cabc, sizeof(cabc));
}
dcs_set_backlight(connector, panel->backlight.level);
}
static int dcs_setup_backlight(struct intel_connector *connector,
enum pipe unused)
{
struct intel_panel *panel = &connector->panel;
panel->backlight.max = PANEL_PWM_MAX_VALUE;
panel->backlight.level = PANEL_PWM_MAX_VALUE;
return 0;
}
int intel_dsi_dcs_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.backlight.type != INTEL_BACKLIGHT_DSI_DCS)
return -ENODEV;
if (WARN_ON(encoder->type != INTEL_OUTPUT_DSI))
return -EINVAL;
panel->backlight.setup = dcs_setup_backlight;
panel->backlight.enable = dcs_enable_backlight;
panel->backlight.disable = dcs_disable_backlight;
panel->backlight.set = dcs_set_backlight;
panel->backlight.get = dcs_get_backlight;
return 0;
}