path: root/drivers/gpu/drm/gma500/cdv_intel_lvds.c

/*
 * Copyright © 2006-2011 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Authors:
 *	Eric Anholt <eric@anholt.net>
 *	Dave Airlie <airlied@linux.ie>
 *	Jesse Barnes <jesse.barnes@intel.com>
 */

#include <linux/i2c.h>
#include <linux/dmi.h>
#include <drm/drmP.h>

#include "intel_bios.h"
#include "psb_drv.h"
#include "psb_intel_drv.h"
#include "psb_intel_reg.h"
#include "power.h"
#include <linux/pm_runtime.h>
#include "cdv_device.h"

/**
 * LVDS I2C backlight control macros
 */
#define BRIGHTNESS_MAX_LEVEL 100
#define BRIGHTNESS_MASK 0xFF
#define BLC_I2C_TYPE	0x01
#define BLC_PWM_TYPT	0x02

#define BLC_POLARITY_NORMAL 0
#define BLC_POLARITY_INVERSE 1

#define PSB_BLC_MAX_PWM_REG_FREQ       (0xFFFE)
#define PSB_BLC_MIN_PWM_REG_FREQ	(0x2)
#define PSB_BLC_PWM_PRECISION_FACTOR	(10)
#define PSB_BACKLIGHT_PWM_CTL_SHIFT	(16)
#define PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR (0xFFFE)

struct cdv_intel_lvds_priv {
	/**
	 * Saved LVDO output states
	 */
	uint32_t savePP_ON;
	uint32_t savePP_OFF;
	uint32_t saveLVDS;
	uint32_t savePP_CONTROL;
	uint32_t savePP_CYCLE;
	uint32_t savePFIT_CONTROL;
	uint32_t savePFIT_PGM_RATIOS;
	uint32_t saveBLC_PWM_CTL;
};

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

	if (gma_power_begin(dev, false)) {
		retval = ((REG_READ(BLC_PWM_CTL) &
			  BACKLIGHT_MODULATION_FREQ_MASK) >>
			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;

		gma_power_end(dev);
	} else
		retval = ((dev_priv->regs.saveBLC_PWM_CTL &
			  BACKLIGHT_MODULATION_FREQ_MASK) >>
			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;

	return retval;
}

#if 0
/*
 * Set LVDS backlight level by I2C command
 */
static int cdv_lvds_i2c_set_brightness(struct drm_device *dev,
					unsigned int level)
{
	struct drm_psb_private *dev_priv = dev->dev_private;
	struct psb_intel_i2c_chan *lvds_i2c_bus = dev_priv->lvds_i2c_bus;
	u8 out_buf[2];
	unsigned int blc_i2c_brightness;

	struct i2c_msg msgs[] = {
		{
			.addr = lvds_i2c_bus->slave_addr,
			.flags = 0,
			.len = 2,
			.buf = out_buf,
		}
	};

	blc_i2c_brightness = BRIGHTNESS_MASK & ((unsigned int)level *
			     BRIGHTNESS_MASK /
			     BRIGHTNESS_MAX_LEVEL);

	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
		blc_i2c_brightness = BRIGHTNESS_MASK - blc_i2c_brightness;

	out_buf[0] = dev_priv->lvds_bl->brightnesscmd;
	out_buf[1] = (u8)blc_i2c_brightness;

	if (i2c_transfer(&lvds_i2c_bus->adapter, msgs, 1) == 1)
		return 0;

	DRM_ERROR("I2C transfer error\n");
	return -1;
}


static int cdv_lvds_pwm_set_brightness(struct drm_device *dev, int level)
{
	struct drm_psb_private *dev_priv = dev->dev_private;

	u32 max_pwm_blc;
	u32 blc_pwm_duty_cycle;

	max_pwm_blc = cdv_intel_lvds_get_max_backlight(dev);

	/*BLC_PWM_CTL Should be initiated while backlight device init*/
	BUG_ON((max_pwm_blc & PSB_BLC_MAX_PWM_REG_FREQ) == 0);

	blc_pwm_duty_cycle = level * max_pwm_blc / BRIGHTNESS_MAX_LEVEL;

	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
		blc_pwm_duty_cycle = max_pwm_blc - blc_pwm_duty_cycle;

	blc_pwm_duty_cycle &= PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR;
	REG_WRITE(BLC_PWM_CTL,
		  (max_pwm_blc << PSB_BACKLIGHT_PWM_CTL_SHIFT) |
		  (blc_pwm_duty_cycle));

	return 0;
}

/*
 * Set LVDS backlight level either by I2C or PWM
 */
void cdv_intel_lvds_set_brightness(struct drm_device *dev, int level)
{
	struct drm_psb_private *dev_priv = dev->dev_private;

	if (!dev_priv->lvds_bl) {
		DRM_ERROR("NO LVDS Backlight Info\n");
		return;
	}

	if (dev_priv->lvds_bl->type == BLC_I2C_TYPE)
		cdv_lvds_i2c_set_brightness(dev, level);
	else
		cdv_lvds_pwm_set_brightness(dev, level);
}
#endif

/**
 * Sets the backlight level.
 *
 * level backlight level, from 0 to cdv_intel_lvds_get_max_backlight().
 */
static void cdv_intel_lvds_set_backlight(struct drm_device *dev, int level)
{
	struct drm_psb_private *dev_priv = dev->dev_private;
	u32 blc_pwm_ctl;

	if (gma_power_begin(dev, false)) {
		blc_pwm_ctl =
			REG_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
		REG_WRITE(BLC_PWM_CTL,
				(blc_pwm_ctl |
				(level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
		gma_power_end(dev);
	} else {
		blc_pwm_ctl = dev_priv->regs.saveBLC_PWM_CTL &
				~BACKLIGHT_DUTY_CYCLE_MASK;
		dev_priv->regs.saveBLC_PWM_CTL = (blc_pwm_ctl |
					(level << BACKLIGHT_DUTY_CYCLE_SHIFT));
	}
}

/**
 * Sets the power state for the panel.
 */
static void cdv_intel_lvds_set_power(struct drm_device *dev,
				     struct drm_encoder *encoder, bool on)
{
	struct drm_psb_private *dev_priv = dev->dev_private;
	u32 pp_status;

	if (!gma_power_begin(dev, true))
		return;

	if (on) {
		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) |
			  POWER_TARGET_ON);
		do {
			pp_status = REG_READ(PP_STATUS);
		} while ((pp_status & PP_ON) == 0);

		cdv_intel_lvds_set_backlight(dev,
				dev_priv->mode_dev.backlight_duty_cycle);
	} else {
		cdv_intel_lvds_set_backlight(dev, 0);

		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
			  ~POWER_TARGET_ON);
		do {
			pp_status = REG_READ(PP_STATUS);
		} while (pp_status & PP_ON);
	}
	gma_power_end(dev);
}

static void cdv_intel_lvds_encoder_dpms(struct drm_encoder *encoder, int mode)
{
	struct drm_device *dev = encoder->dev;
	if (mode == DRM_MODE_DPMS_ON)
		cdv_intel_lvds_set_power(dev, encoder, true);
	else
		cdv_intel_lvds_set_power(dev, encoder, false);
	/* XXX: We never power down the LVDS pairs. */
}

static void cdv_intel_lvds_save(struct drm_connector *connector)
{
}

static void cdv_intel_lvds_restore(struct drm_connector *connector)
{
}

static int cdv_intel_lvds_mode_valid(struct drm_connector *connector,
			      struct drm_display_mode *mode)
{
	struct drm_device *dev = connector->dev;
	struct drm_psb_private *dev_priv = dev->dev_private;
	struct drm_display_mode *fixed_mode =
					dev_priv->mode_dev.panel_fixed_mode;

	/* just in case */
	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
		return MODE_NO_DBLESCAN;

	/* just in case */
	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
		return MODE_NO_INTERLACE;

	if (fixed_mode) {
		if (mode->hdisplay > fixed_mode->hdisplay)
			return MODE_PANEL;
		if (mode->vdisplay > fixed_mode->vdisplay)
			return MODE_PANEL;
	}
	return MODE_OK;
}

static bool cdv_intel_lvds_mode_fixup(struct drm_encoder *encoder,
				  const struct drm_display_mode *mode,
				  struct drm_display_mode *adjusted_mode)
{
	struct drm_device *dev = encoder->dev;
	struct drm_psb_private *dev_priv = dev->