path: root/drivers/gpu/drm/i915/intel_lvds.c

/*
 * Copyright © 2006-2007 Intel Corporation
 * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
 *
 * 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.
 *
 * Authors:
 *	Eric Anholt <eric@anholt.net>
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */

#include <acpi/button.h>
#include <linux/dmi.h>
#include <linux/i2c.h>
#include "drmP.h"
#include "drm.h"
#include "drm_crtc.h"
#include "drm_edid.h"
#include "intel_drv.h"
#include "i915_drm.h"
#include "i915_drv.h"
#include <linux/acpi.h>

/* Private structure for the integrated LVDS support */
struct intel_lvds_priv {
	int fitting_mode;
	u32 pfit_control;
	u32 pfit_pgm_ratios;
};

/**
 * Sets the backlight level.
 *
 * \param level backlight level, from 0 to intel_lvds_get_max_backlight().
 */
static void intel_lvds_set_backlight(struct drm_device *dev, int level)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 blc_pwm_ctl, reg;

	if (IS_IRONLAKE(dev))
		reg = BLC_PWM_CPU_CTL;
	else
		reg = BLC_PWM_CTL;

	blc_pwm_ctl = I915_READ(reg) & ~BACKLIGHT_DUTY_CYCLE_MASK;
	I915_WRITE(reg, (blc_pwm_ctl |
				 (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
}

/**
 * Returns the maximum level of the backlight duty cycle field.
 */
static u32 intel_lvds_get_max_backlight(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 reg;

	if (IS_IRONLAKE(dev))
		reg = BLC_PWM_PCH_CTL2;
	else
		reg = BLC_PWM_CTL;

	return ((I915_READ(reg) & BACKLIGHT_MODULATION_FREQ_MASK) >>
		BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
}

/**
 * Sets the power state for the panel.
 */
static void intel_lvds_set_power(struct drm_device *dev, bool on)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 pp_status, ctl_reg, status_reg;

	if (IS_IRONLAKE(dev)) {
		ctl_reg = PCH_PP_CONTROL;
		status_reg = PCH_PP_STATUS;
	} else {
		ctl_reg = PP_CONTROL;
		status_reg = PP_STATUS;
	}

	if (on) {
		I915_WRITE(ctl_reg, I915_READ(ctl_reg) |
			   POWER_TARGET_ON);
		do {
			pp_status = I915_READ(status_reg);
		} while ((pp_status & PP_ON) == 0);

		intel_lvds_set_backlight(dev, dev_priv->backlight_duty_cycle);
	} else {
		intel_lvds_set_backlight(dev, 0);

		I915_WRITE(ctl_reg, I915_READ(ctl_reg) &
			   ~POWER_TARGET_ON);
		do {
			pp_status = I915_READ(status_reg);
		} while (pp_status & PP_ON);
	}
}

static void intel_lvds_dpms(struct drm_encoder *encoder, int mode)
{
	struct drm_device *dev = encoder->dev;

	if (mode == DRM_MODE_DPMS_ON)
		intel_lvds_set_power(dev, true);
	else
		intel_lvds_set_power(dev, false);

	/* XXX: We never power down the LVDS pairs. */
}

static void intel_lvds_save(struct drm_connector *connector)
{