root/drivers/gpu/drm/gma500/oaktrail_lvds.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright © 2006-2009 Intel Corporation
 *
 * Authors:
 *      Eric Anholt <eric@anholt.net>
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */

#include <linux/i2c.h>
#include <linux/pm_runtime.h>

#include <drm/drm_edid.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_simple_kms_helper.h>

#include "intel_bios.h"
#include "power.h"
#include "psb_drv.h"
#include "psb_intel_drv.h"
#include "psb_intel_reg.h"

/* The max/min PWM frequency in BPCR[31:17] - */
/* The smallest number is 1 (not 0) that can fit in the
 * 15-bit field of the and then*/
/* shifts to the left by one bit to get the actual 16-bit
 * value that the 15-bits correspond to.*/
#define MRST_BLC_MAX_PWM_REG_FREQ           0xFFFF
#define BRIGHTNESS_MAX_LEVEL 100

/*
 * Sets the power state for the panel.
 */
static void oaktrail_lvds_set_power(struct drm_device *dev,
                                struct gma_encoder *gma_encoder,
                                bool on)
{
        u32 pp_status;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);

        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 | PP_READY)) == PP_READY);
                dev_priv->is_lvds_on = true;
                if (dev_priv->ops->lvds_bl_power)
                        dev_priv->ops->lvds_bl_power(dev, true);
        } else {
                if (dev_priv->ops->lvds_bl_power)
                        dev_priv->ops->lvds_bl_power(dev, false);
                REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
                          ~POWER_TARGET_ON);
                do {
                        pp_status = REG_READ(PP_STATUS);
                } while (pp_status & PP_ON);
                dev_priv->is_lvds_on = false;
        }
        gma_power_end(dev);
}

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

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

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

static void oaktrail_lvds_mode_set(struct drm_encoder *encoder,
                               struct drm_display_mode *mode,
                               struct drm_display_mode *adjusted_mode)
{
        struct drm_device *dev = encoder->dev;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
        struct drm_connector_list_iter conn_iter;
        struct drm_connector *connector = NULL;
        struct drm_crtc *crtc = encoder->crtc;
        u32 lvds_port;
        uint64_t v = DRM_MODE_SCALE_FULLSCREEN;

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

        /*
         * The LVDS pin pair will already have been turned on in the
         * psb_intel_crtc_mode_set since it has a large impact on the DPLL
         * settings.
         */
        lvds_port = (REG_READ(LVDS) &
                    (~LVDS_PIPEB_SELECT)) |
                    LVDS_PORT_EN |
                    LVDS_BORDER_EN;

        /* If the firmware says dither on Moorestown, or the BIOS does
           on Oaktrail then enable dithering */
        if (mode_dev->panel_wants_dither || dev_priv->lvds_dither)
                lvds_port |= MRST_PANEL_8TO6_DITHER_ENABLE;

        REG_WRITE(LVDS, lvds_port);

        /* Find the connector we're trying to set up */
        drm_connector_list_iter_begin(dev, &conn_iter);
        drm_for_each_connector_iter(connector, &conn_iter) {
                if (connector->encoder && connector->encoder->crtc == crtc)
                        break;
        }

        if (!connector) {
                drm_connector_list_iter_end(&conn_iter);
                DRM_ERROR("Couldn't find connector when setting mode");
                gma_power_end(dev);
                return;
        }

        drm_object_property_get_value( &connector->base,
                dev->mode_config.scaling_mode_property, &v);
        drm_connector_list_iter_end(&conn_iter);

        if (v == DRM_MODE_SCALE_NO_SCALE)
                REG_WRITE(PFIT_CONTROL, 0);
        else if (v == DRM_MODE_SCALE_ASPECT) {
                if ((mode->vdisplay != adjusted_mode->crtc_vdisplay) ||
                    (mode->hdisplay != adjusted_mode->crtc_hdisplay)) {
                        if ((adjusted_mode->crtc_hdisplay * mode->vdisplay) ==
                            (mode->hdisplay * adjusted_mode->crtc_vdisplay))
                                REG_WRITE(PFIT_CONTROL, PFIT_ENABLE);
                        else if ((adjusted_mode->crtc_hdisplay *
                                mode->vdisplay) > (mode->hdisplay *
                                adjusted_mode->crtc_vdisplay))
                                REG_WRITE(PFIT_CONTROL, PFIT_ENABLE |
                                          PFIT_SCALING_MODE_PILLARBOX);
                        else
                                REG_WRITE(PFIT_CONTROL, PFIT_ENABLE |
                                          PFIT_SCALING_MODE_LETTERBOX);
                } else
                        REG_WRITE(PFIT_CONTROL, PFIT_ENABLE);
        } else /*(v == DRM_MODE_SCALE_FULLSCREEN)*/
                REG_WRITE(PFIT_CONTROL, PFIT_ENABLE);

        gma_power_end(dev);
}

static void oaktrail_lvds_prepare(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        struct gma_encoder *gma_encoder = to_gma_encoder(encoder);
        struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;

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

        mode_dev->saveBLC_PWM_CTL = REG_READ(BLC_PWM_CTL);
        mode_dev->backlight_duty_cycle = (mode_dev->saveBLC_PWM_CTL &
                                          BACKLIGHT_DUTY_CYCLE_MASK);
        oaktrail_lvds_set_power(dev, gma_encoder, false);
        gma_power_end(dev);
}

static u32 oaktrail_lvds_get_max_backlight(struct drm_device *dev)
{
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        u32 ret;

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

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

        return ret;
}

static void oaktrail_lvds_commit(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        struct gma_encoder *gma_encoder = to_gma_encoder(encoder);
        struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;

        if (mode_dev->backlight_duty_cycle == 0)
                mode_dev->backlight_duty_cycle =
                                        oaktrail_lvds_get_max_backlight(dev);
        oaktrail_lvds_set_power(dev, gma_encoder, true);
}

static const struct drm_encoder_helper_funcs oaktrail_lvds_helper_funcs = {
        .dpms = oaktrail_lvds_dpms,
        .mode_fixup = psb_intel_lvds_mode_fixup,
        .prepare = oaktrail_lvds_prepare,
        .mode_set = oaktrail_lvds_mode_set,
        .commit = oaktrail_lvds_commit,
};

/* Returns the panel fixed mode from configuration. */

static void oaktrail_lvds_get_configuration_mode(struct drm_device *dev,
                                        struct psb_intel_mode_device *mode_dev)
{
        struct drm_display_mode *mode = NULL;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        struct oaktrail_timing_info *ti = &dev_priv->gct_data.DTD;

        mode_dev->panel_fixed_mode = NULL;

        /* Use the firmware provided data on Moorestown */
        if (dev_priv->has_gct) {
                mode = kzalloc_obj(*mode);
                if (!mode)
                        return;

                mode->hdisplay = (ti->hactive_hi << 8) | ti->hactive_lo;
                mode->vdisplay = (ti->vactive_hi << 8) | ti->vactive_lo;
                mode->hsync_start = mode->hdisplay + \
                                ((ti->hsync_offset_hi << 8) | \
                                ti->hsync_offset_lo);
                mode->hsync_end = mode->hsync_start + \
                                ((ti->hsync_pulse_width_hi << 8) | \
                                ti->hsync_pulse_width_lo);
                mode->htotal = mode->hdisplay + ((ti->hblank_hi << 8) | \
                                                        ti->hblank_lo);
                mode->vsync_start = \
                        mode->vdisplay + ((ti->vsync_offset_hi << 4) | \
                                                ti->vsync_offset_lo);
                mode->vsync_end = \
                        mode->vsync_start + ((ti->vsync_pulse_width_hi << 4) | \
                                                ti->vsync_pulse_width_lo);
                mode->vtotal = mode->vdisplay + \
                                ((ti->vblank_hi << 8) | ti->vblank_lo);
                mode->clock = ti->pixel_clock * 10;
#if 0
                pr_info("hdisplay is %d\n", mode->hdisplay);
                pr_info("vdisplay is %d\n", mode->vdisplay);
                pr_info("HSS is %d\n", mode->hsync_start);
                pr_info("HSE is %d\n", mode->hsync_end);
                pr_info("htotal is %d\n", mode->htotal);
                pr_info("VSS is %d\n", mode->vsync_start);
                pr_info("VSE is %d\n", mode->vsync_end);
                pr_info("vtotal is %d\n", mode->vtotal);
                pr_info("clock is %d\n", mode->clock);
#endif
                mode_dev->panel_fixed_mode = mode;
        }

        /* Use the BIOS VBT mode if available */
        if (mode_dev->panel_fixed_mode == NULL && mode_dev->vbt_mode)
                mode_dev->panel_fixed_mode = drm_mode_duplicate(dev,
                                                mode_dev->vbt_mode);

        /* Then try the LVDS VBT mode */
        if (mode_dev->panel_fixed_mode == NULL)
                if (dev_priv->lfp_lvds_vbt_mode)
                        mode_dev->panel_fixed_mode =
                                drm_mode_duplicate(dev,
                                        dev_priv->lfp_lvds_vbt_mode);

        /* If we still got no mode then bail */
        if (mode_dev->panel_fixed_mode == NULL)
                return;

        drm_mode_set_name(mode_dev->panel_fixed_mode);
        drm_mode_set_crtcinfo(mode_dev->panel_fixed_mode, 0);
}

/**
 * oaktrail_lvds_init - setup LVDS connectors on this device
 * @dev: drm device
 * @mode_dev: PSB mode device
 *
 * Create the connector, register the LVDS DDC bus, and try to figure out what
 * modes we can display on the LVDS panel (if present).
 */
void oaktrail_lvds_init(struct drm_device *dev,
                    struct psb_intel_mode_device *mode_dev)
{
        struct gma_encoder *gma_encoder;
        struct gma_connector *gma_connector;
        struct gma_i2c_chan *ddc_bus;
        struct drm_connector *connector;
        struct drm_encoder *encoder;
        struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
        struct edid *edid;
        struct i2c_adapter *i2c_adap;
        struct drm_display_mode *scan;  /* *modes, *bios_mode; */
        int ret;

        gma_encoder = kzalloc_obj(struct gma_encoder);
        if (!gma_encoder)
                return;

        gma_connector = kzalloc_obj(struct gma_connector);
        if (!gma_connector)
                goto err_free_encoder;

        connector = &gma_connector->base;
        encoder = &gma_encoder->base;
        dev_priv->is_lvds_on = true;
        ret = drm_connector_init(dev, connector,
                                 &psb_intel_lvds_connector_funcs,
                                 DRM_MODE_CONNECTOR_LVDS);
        if (ret)
                goto err_free_connector;

        ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_LVDS);
        if (ret)
                goto err_connector_cleanup;

        gma_connector_attach_encoder(gma_connector, gma_encoder);
        gma_encoder->type = INTEL_OUTPUT_LVDS;

        drm_encoder_helper_add(encoder, &oaktrail_lvds_helper_funcs);
        drm_connector_helper_add(connector,
                                 &psb_intel_lvds_connector_helper_funcs);
        connector->display_info.subpixel_order = SubPixelHorizontalRGB;
        connector->interlace_allowed = false;
        connector->doublescan_allowed = false;

        drm_object_attach_property(&connector->base,
                                        dev->mode_config.scaling_mode_property,
                                        DRM_MODE_SCALE_FULLSCREEN);
        drm_object_attach_property(&connector->base,
                                        dev_priv->backlight_property,
                                        BRIGHTNESS_MAX_LEVEL);

        mode_dev->panel_wants_dither = false;
        if (dev_priv->has_gct)
                mode_dev->panel_wants_dither = (dev_priv->gct_data.
                        Panel_Port_Control & MRST_PANEL_8TO6_DITHER_ENABLE);
        if (dev_priv->lvds_dither)
                mode_dev->panel_wants_dither = 1;

        /*
         * LVDS discovery:
         * 1) check for EDID on DDC
         * 2) check for VBT data
         * 3) check to see if LVDS is already on
         *    if none of the above, no panel
         * 4) make sure lid is open
         *    if closed, act like it's not there for now
         */

        edid = NULL;
        mutex_lock(&dev->mode_config.mutex);

        i2c_adap = i2c_get_adapter(dev_priv->ops->i2c_bus);
        if (i2c_adap)
                edid = drm_get_edid(connector, i2c_adap);

        if (edid == NULL && dev_priv->lpc_gpio_base) {
                ddc_bus = oaktrail_lvds_i2c_init(dev);
                if (!IS_ERR(ddc_bus)) {
                        i2c_adap = &ddc_bus->base;
                        edid = drm_get_edid(connector, i2c_adap);
                }
        }

        /*
         * Due to the logic in probing for i2c buses above we do not know the
         * i2c_adap until now. Hence we cannot use drm_connector_init_with_ddc()
         * but must instead set connector->ddc manually here.
         */
        connector->ddc = i2c_adap;

        /*
         * Attempt to get the fixed panel mode from DDC.  Assume that the
         * preferred mode is the right one.
         */
        if (edid) {
                drm_connector_update_edid_property(connector, edid);
                drm_add_edid_modes(connector, edid);
                kfree(edid);

                list_for_each_entry(scan, &connector->probed_modes, head) {
                        if (scan->type & DRM_MODE_TYPE_PREFERRED) {
                                mode_dev->panel_fixed_mode =
                                    drm_mode_duplicate(dev, scan);
                                goto out;       /* FIXME: check for quirks */
                        }
                }
        } else
                dev_err(dev->dev, "No ddc adapter available!\n");
        /*
         * If we didn't get EDID, try geting panel timing
         * from configuration data
         */
        oaktrail_lvds_get_configuration_mode(dev, mode_dev);

        if (mode_dev->panel_fixed_mode) {
                mode_dev->panel_fixed_mode->type |= DRM_MODE_TYPE_PREFERRED;
                goto out;       /* FIXME: check for quirks */
        }

        /* If we still don't have a mode after all that, give up. */
        if (!mode_dev->panel_fixed_mode) {
                dev_err(dev->dev, "Found no modes on the lvds, ignoring the LVDS\n");
                goto err_unlock;
        }

out:
        mutex_unlock(&dev->mode_config.mutex);

        return;

err_unlock:
        mutex_unlock(&dev->mode_config.mutex);
        gma_i2c_destroy(to_gma_i2c_chan(connector->ddc));
        drm_encoder_cleanup(encoder);
err_connector_cleanup:
        drm_connector_cleanup(connector);
err_free_connector:
        kfree(gma_connector);
err_free_encoder:
        kfree(gma_encoder);
}