Currently, every different type of backlight hook that i915 supports is pretty straight forward - you have a backlight, probably through PWM (but maybe DPCD), with a single set of platform-specific hooks that are used for controlling it.

HDR backlights, in particular VESA and Intel's HDR backlight implementations, can end up being more complicated. With Intel's proprietary interface, HDR backlight controls always run through the DPCD. When the backlight is in SDR backlight mode however, the driver may need to bypass the TCON and control the backlight directly through PWM.

So, in order to support this we'll need to split our backlight callbacks into two groups: a set of high-level backlight control callbacks in intel_panel, and an additional set of pwm-specific backlight control callbacks. This also implies a functional changes for how these callbacks are used:

* We now keep track of two separate backlight level ranges, one for the high-level backlight, and one for the pwm backlight range * We also keep track of backlight enablement and PWM backlight enablement separately * Since the currently set backlight level might not be the same as the currently programmed PWM backlight level, we stop setting panel->backlight.level with the currently programmed PWM backlight level in panel->backlight.pwm_funcs->setup(). Instead, we rely on the higher level backlight control functions to retrieve the current PWM backlight level (in this case, intel_pwm_get_backlight()). Note that there are still a few PWM backlight setup callbacks that do actually need to retrieve the current PWM backlight level, although we no longer save this value in panel->backlight.level like before.

Additionally, we drop the call to lpt_get_backlight() in lpt_setup_backlight(), and avoid unconditionally writing the PWM value that we get from it and only write it back if we're in CPU mode, and switching to PCH mode. The reason for this is because in the original codepath for this, it was expected that the intel_panel_bl_funcs->setup() hook would be responsible for fetching the initial backlight level. On lpt systems, the only time we could ever be in PCH backlight mode is during the initial driver load - meaning that outside of the setup() hook, lpt_get_backlight() will always be the callback used for retrieving the current backlight level. After this patch we still need to fetch and write-back the PCH backlight value if we're switching from CPU mode to PCH, but because intel_pwm_setup_backlight() will retrieve the backlight level after setup() using the get() hook, which always ends up being lpt_get_backlight(). Thus - an additional call to lpt_get_backlight() in lpt_setup_backlight() is made redundant.

v8: * Go back to getting initial brightness level with intel_pwm_get_backlight(), the other fix we had was definitely wrong. v7: * Use panel->backlight.pwm_funcs->get() to get the backlight level in intel_pwm_setup_backlight(), lest we upset lockdep * Rebase * Rename intel_panel_sanitize_pwm_level() to intel_panel_invert_pwm_level() v6: * Make sure to grab connection_mutex before calling intel_pwm_get_backlight() in intel_pwm_setup_backlight() v5: * Fix indenting warnings from checkpatch v4: * Fix commit message * Remove outdated comment in intel_panel.c * Rename pwm_(min|max) to pwm_level_(min|max) * Use intel_pwm_get_backlight() in intel_pwm_setup_backlight() instead of indirection * Don't move intel_dp_aux_init_bcklight_funcs() call to bottom of intel_panel_init_backlight_funcs() quite yet v3: * Reuse intel_panel_bl_funcs() for pwm_funcs * Explain why we drop lpt_get_backlight()

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Jani Nikula jani.nikula@intel.com Cc: thaytan@noraisin.net Cc: Vasily Khoruzhick anarsoul@gmail.com

squash! drm/i915: Keep track of pwm-related backlight hooks separately

Signed-off-by: Lyude Paul lyude@redhat.com --- .../drm/i915/display/intel_display_types.h | 4 + drivers/gpu/drm/i915/display/intel_panel.c | 331 ++++++++++-------- 2 files changed, 188 insertions(+), 147 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index b1f4ec144207..ee23cc1518df 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -252,6 +252,9 @@ struct intel_panel { bool alternate_pwm_increment; /* lpt+ */

/* PWM chip */ + u32 pwm_level_min; + u32 pwm_level_max; + bool pwm_enabled; bool util_pin_active_low; /* bxt+ */ u8 controller; /* bxt+ only */ struct pwm_device *pwm; @@ -263,6 +266,7 @@ struct intel_panel { struct backlight_device *device;

const struct intel_panel_bl_funcs *funcs; + const struct intel_panel_bl_funcs *pwm_funcs; void (*power)(struct intel_connector *, bool enable); } backlight; }; diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index 7587aaefc7a0..cc2386ef6219 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -511,25 +511,34 @@ static u32 scale_hw_to_user(struct intel_connector *connector, 0, user_max); }

-static u32 intel_panel_compute_brightness(struct intel_connector *connector, - u32 val) +static u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel;

- drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0); + drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);

if (dev_priv->params.invert_brightness < 0) return val;

if (dev_priv->params.invert_brightness > 0 || dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) { - return panel->backlight.max - val + panel->backlight.min; + return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min; }

return val; }

+void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 val) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + + drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val); + panel->backlight.pwm_funcs->set(conn_state, val); +} + static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); @@ -618,12 +627,12 @@ static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 struct intel_panel *panel = &connector->panel; u32 tmp, mask;

- drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0); + drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);

if (panel->backlight.combination_mode) { u8 lbpc;

- lbpc = level * 0xfe / panel->backlight.max + 1; + lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1; level /= lbpc; pci_write_config_byte(dev_priv->drm.pdev, LBPC, lbpc); } @@ -675,9 +684,8 @@ intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, struct drm_i915_private *i915 = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel;

- drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", level); + drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);

- level = intel_panel_compute_brightness(connector, level); panel->backlight.funcs->set(conn_state, level); }

@@ -726,7 +734,7 @@ static void lpt_disable_backlight(const struct drm_connector_state *old_conn_sta struct drm_i915_private *dev_priv = to_i915(connector->base.dev); u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, level); + intel_panel_set_pwm_level(old_conn_state, level);

/* * Although we don't support or enable CPU PWM with LPT/SPT based @@ -754,7 +762,7 @@ static void pch_disable_backlight(const struct drm_connector_state *old_conn_sta struct drm_i915_private *dev_priv = to_i915(connector->base.dev); u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val);

tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2); intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE); @@ -765,7 +773,7 @@ static void pch_disable_backlight(const struct drm_connector_state *old_conn_sta

static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val) { - intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val); }

static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val) @@ -773,7 +781,7 @@ static void i965_disable_backlight(const struct drm_connector_state *old_conn_st struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev); u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val);

tmp = intel_de_read(dev_priv, BLC_PWM_CTL2); intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE); @@ -786,7 +794,7 @@ static void vlv_disable_backlight(const struct drm_connector_state *old_conn_sta enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe; u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val);

tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe)); intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), @@ -800,7 +808,7 @@ static void bxt_disable_backlight(const struct drm_connector_state *old_conn_sta struct intel_panel *panel = &connector->panel; u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val);

tmp = intel_de_read(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller)); @@ -821,7 +829,7 @@ static void cnp_disable_backlight(const struct drm_connector_state *old_conn_sta struct intel_panel *panel = &connector->panel; u32 tmp;

- intel_panel_actually_set_backlight(old_conn_state, val); + intel_panel_set_pwm_level(old_conn_state, val);

tmp = intel_de_read(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller)); @@ -900,7 +908,7 @@ static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken); }

- pch_ctl2 = panel->backlight.max << 16; + pch_ctl2 = panel->backlight.pwm_level_max << 16; intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);

pch_ctl1 = 0; @@ -917,7 +925,7 @@ static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state, pch_ctl1 | BLM_PCH_PWM_ENABLE);

/* This won't stick until the above enable. */ - intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level); }

static void pch_enable_backlight(const struct intel_crtc_state *crtc_state, @@ -952,9 +960,9 @@ static void pch_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);

/* This won't stick until the above enable. */ - intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level);

- pch_ctl2 = panel->backlight.max << 16; + pch_ctl2 = panel->backlight.pwm_level_max << 16; intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);

pch_ctl1 = 0; @@ -981,7 +989,7 @@ static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_write(dev_priv, BLC_PWM_CTL, 0); }

- freq = panel->backlight.max; + freq = panel->backlight.pwm_level_max; if (panel->backlight.combination_mode) freq /= 0xff;

@@ -995,7 +1003,7 @@ static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_posting_read(dev_priv, BLC_PWM_CTL);

/* XXX: combine this into above write? */ - intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level);

/* * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is @@ -1022,7 +1030,7 @@ static void i965_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2); }

- freq = panel->backlight.max; + freq = panel->backlight.pwm_level_max; if (panel->backlight.combination_mode) freq /= 0xff;

@@ -1038,7 +1046,7 @@ static void i965_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_posting_read(dev_priv, BLC_PWM_CTL2); intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);

- intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level); }

static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state, @@ -1057,11 +1065,11 @@ static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state, intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2); }

- ctl = panel->backlight.max << 16; + ctl = panel->backlight.pwm_level_max << 16; intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);

/* XXX: combine this into above write? */ - intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level);

ctl2 = 0; if (panel->backlight.active_low_pwm) @@ -1110,9 +1118,9 @@ static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,

intel_de_write(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller), - panel->backlight.max); + panel->backlight.pwm_level_max);

- intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level);

pwm_ctl = 0; if (panel->backlight.active_low_pwm) @@ -1146,9 +1154,9 @@ static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,

intel_de_write(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller), - panel->backlight.max); + panel->backlight.pwm_level_max);

- intel_panel_actually_set_backlight(conn_state, level); + intel_panel_set_pwm_level(conn_state, level);

pwm_ctl = 0; if (panel->backlight.active_low_pwm) @@ -1168,7 +1176,6 @@ static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state, struct intel_connector *connector = to_intel_connector(conn_state->connector); struct intel_panel *panel = &connector->panel;

- level = intel_panel_compute_brightness(connector, level); pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100); panel->backlight.pwm_state.enabled = true; pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state); @@ -1226,10 +1233,8 @@ static u32 intel_panel_get_backlight(struct intel_connector *connector)

mutex_lock(&dev_priv->backlight_lock);

- if (panel->backlight.enabled) { + if (panel->backlight.enabled) val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector)); - val = intel_panel_compute_brightness(connector, val); - }

mutex_unlock(&dev_priv->backlight_lock);

@@ -1560,13 +1565,13 @@ static u32 get_backlight_max_vbt(struct intel_connector *connector) u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv); u32 pwm;

- if (!panel->backlight.funcs->hz_to_pwm) { + if (!panel->backlight.pwm_funcs->hz_to_pwm) { drm_dbg_kms(&dev_priv->drm, "backlight frequency conversion not supported\n"); return 0; }

- pwm = panel->backlight.funcs->hz_to_pwm(connector, pwm_freq_hz); + pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz); if (!pwm) { drm_dbg_kms(&dev_priv->drm, "backlight frequency conversion failed\n"); @@ -1585,7 +1590,7 @@ static u32 get_backlight_min_vbt(struct intel_connector *connector) struct intel_panel *panel = &connector->panel; int min;

- drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0); + drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);

/* * XXX: If the vbt value is 255, it makes min equal to max, which leads @@ -1602,7 +1607,7 @@ static u32 get_backlight_min_vbt(struct intel_connector *connector) }

/* vbt value is a coefficient in range [0..255] */ - return scale(min, 0, 255, 0, panel->backlight.max); + return scale(min, 0, 255, 0, panel->backlight.pwm_level_max); }

static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused) @@ -1622,29 +1627,28 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;

pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2); - panel->backlight.max = pch_ctl2 >> 16; + panel->backlight.pwm_level_max = pch_ctl2 >> 16;

cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

- panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

- panel->backlight.enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE; + panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;

- cpu_mode = panel->backlight.enabled && HAS_PCH_LPT(dev_priv) && + cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) && !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) && (cpu_ctl2 & BLM_PWM_ENABLE); - if (cpu_mode) - val = pch_get_backlight(connector, unused); - else - val = lpt_get_backlight(connector, unused);

if (cpu_mode) { + val = intel_panel_invert_pwm_level(connector, + pch_get_backlight(connector, unused)); + drm_dbg_kms(&dev_priv->drm, "CPU backlight register was enabled, switching to PCH override\n");

@@ -1657,7 +1661,7 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus cpu_ctl2 & ~BLM_PWM_ENABLE); }

- val = intel_panel_compute_brightness(connector, val); + val = intel_panel_invert_pwm_level(connector, val); panel->backlight.level = clamp(val, panel->backlight.min, panel->backlight.max);

@@ -1668,29 +1672,24 @@ static int pch_setup_backlight(struct intel_connector *connector, enum pipe unus { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; - u32 cpu_ctl2, pch_ctl1, pch_ctl2, val; + u32 cpu_ctl2, pch_ctl1, pch_ctl2;

pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1); panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;

pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2); - panel->backlight.max = pch_ctl2 >> 16; + panel->backlight.pwm_level_max = pch_ctl2 >> 16;

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

- panel->backlight.min = get_backlight_min_vbt(connector); - - val = pch_get_backlight(connector, unused); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2); - panel->backlight.enabled = (cpu_ctl2 & BLM_PWM_ENABLE) && + panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) && (pch_ctl1 & BLM_PCH_PWM_ENABLE);

return 0; @@ -1710,27 +1709,26 @@ static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unu if (IS_PINEVIEW(dev_priv)) panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;

- panel->backlight.max = ctl >> 17; + panel->backlight.pwm_level_max = ctl >> 17;

- if (!panel->backlight.max) { - panel->backlight.max = get_backlight_max_vbt(connector); - panel->backlight.max >>= 1; + if (!panel->backlight.pwm_level_max) { + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector); + panel->backlight.pwm_level_max >>= 1; }

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

if (panel->backlight.combination_mode) - panel->backlight.max *= 0xff; + panel->backlight.pwm_level_max *= 0xff;

- panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

val = i9xx_get_backlight(connector, unused); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); + val = intel_panel_invert_pwm_level(connector, val); + val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);

- panel->backlight.enabled = val != 0; + panel->backlight.pwm_enabled = val != 0;

return 0; } @@ -1739,32 +1737,27 @@ static int i965_setup_backlight(struct intel_connector *connector, enum pipe unu { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; - u32 ctl, ctl2, val; + u32 ctl, ctl2;

ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2); panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE; panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;

ctl = intel_de_read(dev_priv, BLC_PWM_CTL); - panel->backlight.max = ctl >> 16; + panel->backlight.pwm_level_max = ctl >> 16;

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

if (panel->backlight.combination_mode) - panel->backlight.max *= 0xff; + panel->backlight.pwm_level_max *= 0xff;

- panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

- val = i9xx_get_backlight(connector, unused); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); - - panel->backlight.enabled = ctl2 & BLM_PWM_ENABLE; + panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;

return 0; } @@ -1773,7 +1766,7 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; - u32 ctl, ctl2, val; + u32 ctl, ctl2;

if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B)) return -ENODEV; @@ -1782,22 +1775,17 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;

ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)); - panel->backlight.max = ctl >> 16; + panel->backlight.pwm_level_max = ctl >> 16;

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

- panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

- val = vlv_get_backlight(connector, pipe); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); - - panel->backlight.enabled = ctl2 & BLM_PWM_ENABLE; + panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;

return 0; } @@ -1822,24 +1810,18 @@ bxt_setup_backlight(struct intel_connector *connector, enum pipe unused) }

panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY; - panel->backlight.max = - intel_de_read(dev_priv, - BXT_BLC_PWM_FREQ(panel->backlight.controller)); + panel->backlight.pwm_level_max = + intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

- panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

- val = bxt_get_backlight(connector, unused); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); - - panel->backlight.enabled = pwm_ctl & BXT_BLC_PWM_ENABLE; + panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;

return 0; } @@ -1849,7 +1831,7 @@ cnp_setup_backlight(struct intel_connector *connector, enum pipe unused) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; - u32 pwm_ctl, val; + u32 pwm_ctl;

/* * CNP has the BXT implementation of backlight, but with only one @@ -1862,24 +1844,18 @@ cnp_setup_backlight(struct intel_connector *connector, enum pipe unused) BXT_BLC_PWM_CTL(panel->backlight.controller));

panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY; - panel->backlight.max = - intel_de_read(dev_priv, - BXT_BLC_PWM_FREQ(panel->backlight.controller)); + panel->backlight.pwm_level_max = + intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));

- if (!panel->backlight.max) - panel->backlight.max = get_backlight_max_vbt(connector); + if (!panel->backlight.pwm_level_max) + panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);

- if (!panel->backlight.max) + if (!panel->backlight.pwm_level_max) return -ENODEV;

- panel->backlight.min = get_backlight_min_vbt(connector); - - val = bxt_get_backlight(connector, unused); - val = intel_panel_compute_brightness(connector, val); - panel->backlight.level = clamp(val, panel->backlight.min, - panel->backlight.max); + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

- panel->backlight.enabled = pwm_ctl & BXT_BLC_PWM_ENABLE; + panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;

return 0; } @@ -1909,8 +1885,8 @@ static int ext_pwm_setup_backlight(struct intel_connector *connector, return -ENODEV; }

- panel->backlight.max = 100; /* 100% */ - panel->backlight.min = get_backlight_min_vbt(connector); + panel->backlight.pwm_level_max = 100; /* 100% */ + panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);

if (pwm_is_enabled(panel->backlight.pwm)) { /* PWM is already enabled, use existing settings */ @@ -1918,10 +1894,8 @@ static int ext_pwm_setup_backlight(struct intel_connector *connector,

level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state, 100); - level = intel_panel_compute_brightness(connector, level); - panel->backlight.level = clamp(level, panel->backlight.min, - panel->backlight.max); - panel->backlight.enabled = true; + level = intel_panel_invert_pwm_level(connector, level); + panel->backlight.pwm_enabled = true;

drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n", NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period, @@ -1937,6 +1911,58 @@ static int ext_pwm_setup_backlight(struct intel_connector *connector, return 0; }

+static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + panel->backlight.pwm_funcs->set(conn_state, + intel_panel_invert_pwm_level(connector, level)); +} + +static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct intel_panel *panel = &connector->panel; + + return intel_panel_invert_pwm_level(connector, + panel->backlight.pwm_funcs->get(connector, pipe)); +} + +static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + panel->backlight.pwm_funcs->enable(crtc_state, conn_state, + intel_panel_invert_pwm_level(connector, level)); +} + +static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + panel->backlight.pwm_funcs->disable(conn_state, + intel_panel_invert_pwm_level(connector, level)); +} + +static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct intel_panel *panel = &connector->panel; + int ret = panel->backlight.pwm_funcs->setup(connector, pipe); + + if (ret < 0) + return ret; + + panel->backlight.min = panel->backlight.pwm_level_min; + panel->backlight.max = panel->backlight.pwm_level_max; + panel->backlight.level = intel_pwm_get_backlight(connector, pipe); + panel->backlight.enabled = panel->backlight.pwm_enabled; + + return 0; +} + void intel_panel_update_backlight(struct intel_atomic_state *state, struct intel_encoder *encoder, const struct intel_crtc_state *crtc_state, @@ -2010,7 +2036,7 @@ static void intel_panel_destroy_backlight(struct intel_panel *panel) panel->backlight.present = false; }

-static const struct intel_panel_bl_funcs bxt_funcs = { +static const struct intel_panel_bl_funcs bxt_pwm_funcs = { .setup = bxt_setup_backlight, .enable = bxt_enable_backlight, .disable = bxt_disable_backlight, @@ -2019,7 +2045,7 @@ static const struct intel_panel_bl_funcs bxt_funcs = { .hz_to_pwm = bxt_hz_to_pwm, };

-static const struct intel_panel_bl_funcs cnp_funcs = { +static const struct intel_panel_bl_funcs cnp_pwm_funcs = { .setup = cnp_setup_backlight, .enable = cnp_enable_backlight, .disable = cnp_disable_backlight, @@ -2028,7 +2054,7 @@ static const struct intel_panel_bl_funcs cnp_funcs = { .hz_to_pwm = cnp_hz_to_pwm, };

-static const struct intel_panel_bl_funcs lpt_funcs = { +static const struct intel_panel_bl_funcs lpt_pwm_funcs = { .setup = lpt_setup_backlight, .enable = lpt_enable_backlight, .disable = lpt_disable_backlight, @@ -2037,7 +2063,7 @@ static const struct intel_panel_bl_funcs lpt_funcs = { .hz_to_pwm = lpt_hz_to_pwm, };

-static const struct intel_panel_bl_funcs spt_funcs = { +static const struct intel_panel_bl_funcs spt_pwm_funcs = { .setup = lpt_setup_backlight, .enable = lpt_enable_backlight, .disable = lpt_disable_backlight, @@ -2046,7 +2072,7 @@ static const struct intel_panel_bl_funcs spt_funcs = { .hz_to_pwm = spt_hz_to_pwm, };

-static const struct intel_panel_bl_funcs pch_funcs = { +static const struct intel_panel_bl_funcs pch_pwm_funcs = { .setup = pch_setup_backlight, .enable = pch_enable_backlight, .disable = pch_disable_backlight, @@ -2063,7 +2089,7 @@ static const struct intel_panel_bl_funcs ext_pwm_funcs = { .get = ext_pwm_get_backlight, };

-static const struct intel_panel_bl_funcs vlv_funcs = { +static const struct intel_panel_bl_funcs vlv_pwm_funcs = { .setup = vlv_setup_backlight, .enable = vlv_enable_backlight, .disable = vlv_disable_backlight, @@ -2072,7 +2098,7 @@ static const struct intel_panel_bl_funcs vlv_funcs = { .hz_to_pwm = vlv_hz_to_pwm, };

-static const struct intel_panel_bl_funcs i965_funcs = { +static const struct intel_panel_bl_funcs i965_pwm_funcs = { .setup = i965_setup_backlight, .enable = i965_enable_backlight, .disable = i965_disable_backlight, @@ -2081,7 +2107,7 @@ static const struct intel_panel_bl_funcs i965_funcs = { .hz_to_pwm = i965_hz_to_pwm, };

-static const struct intel_panel_bl_funcs i9xx_funcs = { +static const struct intel_panel_bl_funcs i9xx_pwm_funcs = { .setup = i9xx_setup_backlight, .enable = i9xx_enable_backlight, .disable = i9xx_disable_backlight, @@ -2090,6 +2116,14 @@ static const struct intel_panel_bl_funcs i9xx_funcs = { .hz_to_pwm = i9xx_hz_to_pwm, };

+static const struct intel_panel_bl_funcs pwm_bl_funcs = { + .setup = intel_pwm_setup_backlight, + .enable = intel_pwm_enable_backlight, + .disable = intel_pwm_disable_backlight, + .set = intel_pwm_set_backlight, + .get = intel_pwm_get_backlight, +}; + /* Set up chip specific backlight functions */ static void intel_panel_init_backlight_funcs(struct intel_panel *panel) @@ -2107,27 +2141,30 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel) return;

if (IS_GEN9_LP(dev_priv)) { - panel->backlight.funcs = &bxt_funcs; + panel->backlight.pwm_funcs = &bxt_pwm_funcs; } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) { - panel->backlight.funcs = &cnp_funcs; + panel->backlight.pwm_funcs = &cnp_pwm_funcs; } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) { if (HAS_PCH_LPT(dev_priv)) - panel->backlight.funcs = &lpt_funcs; + panel->backlight.pwm_funcs = &lpt_pwm_funcs; else - panel->backlight.funcs = &spt_funcs; + panel->backlight.pwm_funcs = &spt_pwm_funcs; } else if (HAS_PCH_SPLIT(dev_priv)) { - panel->backlight.funcs = &pch_funcs; + panel->backlight.pwm_funcs = &pch_pwm_funcs; } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) { if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) { - panel->backlight.funcs = &ext_pwm_funcs; + panel->backlight.pwm_funcs = &ext_pwm_funcs; } else { - panel->backlight.funcs = &vlv_funcs; + panel->backlight.pwm_funcs = &vlv_pwm_funcs; } } else if (IS_GEN(dev_priv, 4)) { - panel->backlight.funcs = &i965_funcs; + panel->backlight.pwm_funcs = &i965_pwm_funcs; } else { - panel->backlight.funcs = &i9xx_funcs; + panel->backlight.pwm_funcs = &i9xx_pwm_funcs; } + + /* We're using a standard PWM backlight interface */ + panel->backlight.funcs = &pwm_bl_funcs; }

enum drm_connector_status

So-recently a bunch of laptops on the market have started using DPCD backlight controls instead of the traditional DDI backlight controls. Originally we thought we had this handled by adding VESA backlight control support to i915, but the story ended up being a lot more complicated then that.

Simply put-there's two main backlight interfaces Intel can see in the wild. Intel's proprietary HDR backlight interface, and the standard VESA backlight interface. Note that many panels have been observed to report support for both backlight interfaces, but testing has shown far more panels work with the Intel HDR backlight interface at the moment. Additionally, the VBT appears to be capable of reporting support for the VESA backlight interface but not the Intel HDR interface which needs to be probed by setting the right magic OUI.

On top of that however, there's also actually two different variants of the Intel HDR backlight interface. The first uses the AUX channel for controlling the brightness of the screen in both SDR and HDR mode, and the second only uses the AUX channel for setting the brightness level in HDR mode - relying on PWM for setting the brightness level in SDR mode.

For the time being we've been using EDIDs to maintain a list of quirks for panels that safely do support the VESA backlight interface. Adding support for Intel's HDR backlight interface in addition however, should finally allow us to auto-detect eDP backlight controls properly so long as we probe like so:

* If the panel's VBT reports VESA backlight support, assume it really does support it * If the panel's VBT reports DDI backlight controls: * First probe for Intel's HDR backlight interface * If that fails, probe for VESA's backlight interface * If that fails, assume no DPCD backlight control * If the panel's VBT reports any other backlight type: just assume it doesn't have DPCD backlight controls

Changes since v4: * Fix checkpatch issues Changes since v3: * Stop using drm_device and use drm_i915_private instead * Don't forget to return from intel_dp_aux_hdr_get_backlight() if we fail to read the current backlight mode from the DPCD * s/uint8_t/u8/ * Remove unneeded parenthesis in intel_dp_aux_hdr_enable_backlight() * Use drm_dbg_kms() in intel_dp_aux_init_backlight_funcs()

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Jani Nikula jani.nikula@intel.com Cc: thaytan@noraisin.net Cc: Vasily Khoruzhick anarsoul@gmail.com --- .../drm/i915/display/intel_display_types.h | 9 +- .../drm/i915/display/intel_dp_aux_backlight.c | 247 ++++++++++++++++-- drivers/gpu/drm/i915/display/intel_panel.c | 40 ++- drivers/gpu/drm/i915/display/intel_panel.h | 4 + 4 files changed, 269 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h index ee23cc1518df..a2ea651ece79 100644 --- a/drivers/gpu/drm/i915/display/intel_display_types.h +++ b/drivers/gpu/drm/i915/display/intel_display_types.h @@ -261,7 +261,14 @@ struct intel_panel { struct pwm_state pwm_state;

/* DPCD backlight */ - u8 pwmgen_bit_count; + union { + struct { + u8 pwmgen_bit_count; + } vesa; + struct { + bool sdr_uses_aux; + } intel; + } edp;

struct backlight_device *device;

diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index de764dae1e66..9b0589cf8d17 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -22,8 +22,26 @@ * */

+/* + * Laptops with Intel GPUs which have panels that support controlling the + * backlight through DP AUX can actually use two different interfaces: Intel's + * proprietary DP AUX backlight interface, and the standard VESA backlight + * interface. Unfortunately, at the time of writing this a lot of laptops will + * advertise support for the standard VESA backlight interface when they + * don't properly support it. However, on these systems the Intel backlight + * interface generally does work properly. Additionally, these systems will + * usually just indicate that they use PWM backlight controls in their VBIOS + * for some reason. + */ + #include "intel_display_types.h" #include "intel_dp_aux_backlight.h" +#include "intel_panel.h" + +/* TODO: + * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we + * can make people's backlights work in the mean time + */

/* * DP AUX registers for Intel's proprietary HDR backlight interface. We define @@ -77,6 +95,178 @@

#define INTEL_EDP_BRIGHTNESS_OPTIMIZATION_1 0x359

+/* Intel EDP backlight callbacks */ +static bool +intel_dp_aux_supports_hdr_backlight(struct intel_connector *connector) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + struct drm_dp_aux *aux = &intel_dp->aux; + struct intel_panel *panel = &connector->panel; + int ret; + u8 tcon_cap[4]; + + ret = drm_dp_dpcd_read(aux, INTEL_EDP_HDR_TCON_CAP0, tcon_cap, sizeof(tcon_cap)); + if (ret < 0) + return false; + + if (!(tcon_cap[1] & INTEL_EDP_HDR_TCON_BRIGHTNESS_NITS_CAP)) + return false; + + if (tcon_cap[0] >= 1) { + drm_dbg_kms(&i915->drm, "Detected Intel HDR backlight interface version %d\n", + tcon_cap[0]); + } else { + drm_dbg_kms(&i915->drm, "Detected unsupported HDR backlight interface version %d\n", + tcon_cap[0]); + return false; + } + + panel->backlight.edp.intel.sdr_uses_aux = + tcon_cap[2] & INTEL_EDP_SDR_TCON_BRIGHTNESS_AUX_CAP; + + return true; +} + +static u32 +intel_dp_aux_hdr_get_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + u8 tmp; + u8 buf[2] = { 0 }; + + if (drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &tmp) < 0) { + drm_err(&i915->drm, "Failed to read current backlight mode from DPCD\n"); + return 0; + } + + if (!(tmp & INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE)) { + if (!panel->backlight.edp.intel.sdr_uses_aux) { + u32 pwm_level = panel->backlight.pwm_funcs->get(connector, pipe); + + return intel_panel_backlight_level_from_pwm(connector, pwm_level); + } + + /* Assume 100% brightness if backlight controls aren't enabled yet */ + return panel->backlight.max; + } + + if (drm_dp_dpcd_read(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, sizeof(buf)) < 0) { + drm_err(&i915->drm, "Failed to read brightness from DPCD\n"); + return 0; + } + + return (buf[1] << 8 | buf[0]); +} + +static void +intel_dp_aux_hdr_set_aux_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct drm_device *dev = connector->base.dev; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + u8 buf[4] = { 0 }; + + buf[0] = level & 0xFF; + buf[1] = (level & 0xFF00) >> 8; + + if (drm_dp_dpcd_write(&intel_dp->aux, INTEL_EDP_BRIGHTNESS_NITS_LSB, buf, 4) < 0) + drm_err(dev, "Failed to write brightness level to DPCD\n"); +} + +static void +intel_dp_aux_hdr_set_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + if (panel->backlight.edp.intel.sdr_uses_aux) { + intel_dp_aux_hdr_set_aux_backlight(conn_state, level); + } else { + const u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level); + + intel_panel_set_pwm_level(conn_state, pwm_level); + } +} + +static void +intel_dp_aux_hdr_enable_backlight(const struct intel_crtc_state *crtc_state, + const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); + int ret; + u8 old_ctrl, ctrl; + + ret = drm_dp_dpcd_readb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, &old_ctrl); + if (ret < 0) { + drm_err(&i915->drm, "Failed to read current backlight control mode: %d\n", ret); + return; + } + + ctrl = old_ctrl; + if (panel->backlight.edp.intel.sdr_uses_aux) { + ctrl |= INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE; + intel_dp_aux_hdr_set_aux_backlight(conn_state, level); + } else { + u32 pwm_level = intel_panel_backlight_level_to_pwm(connector, level); + + panel->backlight.pwm_funcs->enable(crtc_state, conn_state, pwm_level); + + ctrl &= ~INTEL_EDP_HDR_TCON_BRIGHTNESS_AUX_ENABLE; + } + + if (ctrl != old_ctrl) + if (drm_dp_dpcd_writeb(&intel_dp->aux, INTEL_EDP_HDR_GETSET_CTRL_PARAMS, ctrl) < 0) + drm_err(&i915->drm, "Failed to configure DPCD brightness controls\n"); +} + +static void +intel_dp_aux_hdr_disable_backlight(const struct drm_connector_state *conn_state, u32 level) +{ + struct intel_connector *connector = to_intel_connector(conn_state->connector); + struct intel_panel *panel = &connector->panel; + + /* Nothing to do for AUX based backlight controls */ + if (panel->backlight.edp.intel.sdr_uses_aux) + return; + + /* Note we want the actual pwm_level to be 0, regardless of pwm_min */ + panel->backlight.pwm_funcs->disable(conn_state, intel_panel_invert_pwm_level(connector, 0)); +} + +static int +intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pipe) +{ + struct drm_i915_private *i915 = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + int ret; + + if (panel->backlight.edp.intel.sdr_uses_aux) { + drm_dbg_kms(&i915->drm, "SDR backlight is controlled through DPCD\n"); + } else { + drm_dbg_kms(&i915->drm, "SDR backlight is controlled through PWM\n"); + + ret = panel->backlight.pwm_funcs->setup(connector, pipe); + if (ret < 0) { + drm_err(&i915->drm, + "Failed to setup SDR backlight controls through PWM: %d\n", ret); + return ret; + } + } + + panel->backlight.max = 512; + panel->backlight.min = 0; + panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector, pipe); + panel->backlight.enabled = panel->backlight.level != 0; + + return 0; +} + /* VESA backlight callbacks */ static void set_vesa_backlight_enable(struct intel_dp *intel_dp, bool enable) { @@ -195,7 +385,7 @@ static bool intel_dp_aux_vesa_set_pwm_freq(struct intel_connector *connector) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_dp *intel_dp = intel_attached_dp(connector); - const u8 pn = connector->panel.backlight.pwmgen_bit_count; + const u8 pn = connector->panel.backlight.edp.vesa.pwmgen_bit_count; int freq, fxp, f, fxp_actual, fxp_min, fxp_max;

freq = dev_priv->vbt.backlight.pwm_freq_hz; @@ -236,6 +426,7 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state, struct drm_i915_private *i915 = dp_to_i915(intel_dp); struct intel_panel *panel = &connector->panel; u8 dpcd_buf, new_dpcd_buf, edp_backlight_mode; + u8 pwmgen_bit_count = panel->backlight.edp.vesa.pwmgen_bit_count;

if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, &dpcd_buf) != 1) { @@ -256,7 +447,7 @@ intel_dp_aux_vesa_enable_backlight(const struct intel_crtc_state *crtc_state,

if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, - panel->backlight.pwmgen_bit_count) < 0) + pwmgen_bit_count) < 0) drm_dbg_kms(&i915->drm, "Failed to write aux pwmgen bit count\n");

@@ -364,7 +555,7 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto "Failed to write aux pwmgen bit count\n"); return max_backlight; } - panel->backlight.pwmgen_bit_count = pn; + panel->backlight.edp.vesa.pwmgen_bit_count = pn;

max_backlight = (1 << pn) - 1;

@@ -405,6 +596,14 @@ intel_dp_aux_supports_vesa_backlight(struct intel_connector *connector) return false; }

+static const struct intel_panel_bl_funcs intel_dp_hdr_bl_funcs = { + .setup = intel_dp_aux_hdr_setup_backlight, + .enable = intel_dp_aux_hdr_enable_backlight, + .disable = intel_dp_aux_hdr_disable_backlight, + .set = intel_dp_aux_hdr_set_backlight, + .get = intel_dp_aux_hdr_get_backlight, +}; + static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = { .setup = intel_dp_aux_vesa_setup_backlight, .enable = intel_dp_aux_vesa_enable_backlight, @@ -413,36 +612,34 @@ static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = { .get = intel_dp_aux_vesa_get_backlight, };

-int intel_dp_aux_init_backlight_funcs(struct intel_connector *intel_connector) +int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) { - struct intel_panel *panel = &intel_connector->panel; - struct intel_dp *intel_dp = enc_to_intel_dp(intel_connector->encoder); + struct drm_device *dev = connector->base.dev; + struct intel_panel *panel = &connector->panel; + struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); struct drm_i915_private *i915 = dp_to_i915(intel_dp);

- if (i915->params.enable_dpcd_backlight == 0 || - !intel_dp_aux_supports_vesa_backlight(intel_connector)) + if (i915->params.enable_dpcd_backlight == 0) return -ENODEV;

/* - * There are a lot of machines that don't advertise the backlight - * control interface to use properly in their VBIOS, :\ + * A lot of eDP panels in the wild will report supporting both the + * Intel proprietary backlight control interface, and the VESA + * backlight control interface. Many of these panels are liars though, + * and will only work with the Intel interface. So, always probe for + * that first. */ - if (i915->vbt.backlight.type != - INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE && - i915->params.enable_dpcd_backlight != 1 && - !drm_dp_has_quirk(&intel_dp->desc, intel_dp->edid_quirks, - DP_QUIRK_FORCE_DPCD_BACKLIGHT)) { - drm_info(&i915->drm, - "Panel advertises DPCD backlight support, but " - "VBT disagrees. If your backlight controls " - "don't work try booting with " - "i915.enable_dpcd_backlight=1. If your machine " - "needs this, please file a _new_ bug report on " - "drm/i915, see " FDO_BUG_URL " for details.\n"); - return -ENODEV; + if (intel_dp_aux_supports_hdr_backlight(connector)) { + drm_dbg_kms(dev, "Using Intel proprietary eDP backlight controls\n"); + panel->backlight.funcs = &intel_dp_hdr_bl_funcs; + return 0; }

- panel->backlight.funcs = &intel_dp_vesa_bl_funcs; + if (intel_dp_aux_supports_vesa_backlight(connector)) { + drm_dbg_kms(dev, "Using VESA eDP backlight controls\n"); + panel->backlight.funcs = &intel_dp_vesa_bl_funcs; + return 0; + }

- return 0; + return -ENODEV; } diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c index cc2386ef6219..6b1e53664d3d 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.c +++ b/drivers/gpu/drm/i915/display/intel_panel.c @@ -511,7 +511,7 @@ static u32 scale_hw_to_user(struct intel_connector *connector, 0, user_max); }

-static u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val) +u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); struct intel_panel *panel = &connector->panel; @@ -539,6 +539,36 @@ void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 panel->backlight.pwm_funcs->set(conn_state, val); }

+u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 val) +{ + struct drm_i915_private *dev_priv = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + + drm_WARN_ON_ONCE(&dev_priv->drm, + panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0); + + val = scale(val, panel->backlight.min, panel->backlight.max, + panel->backlight.pwm_level_min, panel->backlight.pwm_level_max); + + return intel_panel_invert_pwm_level(connector, val); +} + +u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val) +{ + struct drm_i915_private *dev_priv = to_i915(connector->base.dev); + struct intel_panel *panel = &connector->panel; + + drm_WARN_ON_ONCE(&dev_priv->drm, + panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0); + + if (dev_priv->params.invert_brightness > 0 || + (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS)) + val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min); + + return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max, + panel->backlight.min, panel->backlight.max); +} + static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused) { struct drm_i915_private *dev_priv = to_i915(connector->base.dev); @@ -2132,10 +2162,6 @@ 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_eDP && - intel_dp_aux_init_backlight_funcs(connector) == 0) - return; - if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI && intel_dsi_dcs_init_backlight_funcs(connector) == 0) return; @@ -2163,6 +2189,10 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel) panel->backlight.pwm_funcs = &i9xx_pwm_funcs; }

+ if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP && + intel_dp_aux_init_backlight_funcs(connector) == 0) + return; + /* We're using a standard PWM backlight interface */ panel->backlight.funcs = &pwm_bl_funcs; } diff --git a/drivers/gpu/drm/i915/display/intel_panel.h b/drivers/gpu/drm/i915/display/intel_panel.h index 5b813fe90557..1d340f77bffc 100644 --- a/drivers/gpu/drm/i915/display/intel_panel.h +++ b/drivers/gpu/drm/i915/display/intel_panel.h @@ -49,6 +49,10 @@ struct drm_display_mode * intel_panel_edid_fixed_mode(struct intel_connector *connector); struct drm_display_mode * intel_panel_vbt_fixed_mode(struct intel_connector *connector); +void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 level); +u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 level); +u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 level); +u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val);

#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE) int intel_backlight_device_register(struct intel_connector *connector);

Since we now support controlling panel backlights through DPCD using both the standard VESA interface, and Intel's proprietary HDR backlight interface, we should allow the user to be able to explicitly choose between one or the other in the event that we're wrong about panels reliably reporting support for the Intel HDR interface.

So, this commit adds support for this by introducing two new enable_dpcd_backlight options: 2 which forces i915 to only probe for the VESA interface, and 3 which forces i915 to only probe for the Intel backlight interface (might be useful if we find panels in the wild that report the VESA interface in their VBT, but actually only support the Intel backlight interface).

v3: * Rebase

Signed-off-by: Lyude Paul lyude@redhat.com Reviewed-by: Jani Nikula jani.nikula@intel.com Cc: thaytan@noraisin.net Cc: Vasily Khoruzhick anarsoul@gmail.com --- .../drm/i915/display/intel_dp_aux_backlight.c | 45 +++++++++++++++++-- drivers/gpu/drm/i915/i915_params.c | 2 +- 2 files changed, 43 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 9b0589cf8d17..31a478f63d52 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -612,15 +612,54 @@ static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = { .get = intel_dp_aux_vesa_get_backlight, };

+enum intel_dp_aux_backlight_modparam { + INTEL_DP_AUX_BACKLIGHT_AUTO = -1, + INTEL_DP_AUX_BACKLIGHT_OFF = 0, + INTEL_DP_AUX_BACKLIGHT_ON = 1, + INTEL_DP_AUX_BACKLIGHT_FORCE_VESA = 2, + INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL = 3, +}; + int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) { struct drm_device *dev = connector->base.dev; struct intel_panel *panel = &connector->panel; struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); struct drm_i915_private *i915 = dp_to_i915(intel_dp); + bool try_intel_interface = false, try_vesa_interface = false;

- if (i915->params.enable_dpcd_backlight == 0) + /* Check the VBT and user's module parameters to figure out which + * interfaces to probe + */ + switch (i915->params.enable_dpcd_backlight) { + case INTEL_DP_AUX_BACKLIGHT_OFF: return -ENODEV; + case INTEL_DP_AUX_BACKLIGHT_AUTO: + switch (i915->vbt.backlight.type) { + case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE: + try_vesa_interface = true; + break; + case INTEL_BACKLIGHT_DISPLAY_DDI: + try_intel_interface = true; + try_vesa_interface = true; + break; + default: + return -ENODEV; + } + break; + case INTEL_DP_AUX_BACKLIGHT_ON: + if (i915->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE) + try_intel_interface = true; + + try_vesa_interface = true; + break; + case INTEL_DP_AUX_BACKLIGHT_FORCE_VESA: + try_vesa_interface = true; + break; + case INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL: + try_intel_interface = true; + break; + }

/* * A lot of eDP panels in the wild will report supporting both the @@ -629,13 +668,13 @@ int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) * and will only work with the Intel interface. So, always probe for * that first. */ - if (intel_dp_aux_supports_hdr_backlight(connector)) { + if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) { drm_dbg_kms(dev, "Using Intel proprietary eDP backlight controls\n"); panel->backlight.funcs = &intel_dp_hdr_bl_funcs; return 0; }

- if (intel_dp_aux_supports_vesa_backlight(connector)) { + if (try_vesa_interface && intel_dp_aux_supports_vesa_backlight(connector)) { drm_dbg_kms(dev, "Using VESA eDP backlight controls\n"); panel->backlight.funcs = &intel_dp_vesa_bl_funcs; return 0; diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 7f139ea4a90b..6939634e56ed 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -185,7 +185,7 @@ i915_param_named_unsafe(inject_probe_failure, uint, 0400,

i915_param_named(enable_dpcd_backlight, int, 0400, "Enable support for DPCD backlight control" - "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enabled)"); + "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enable, 2=force VESA interface, 3=force Intel interface)");

#if IS_ENABLED(CONFIG_DRM_I915_GVT) i915_param_named(enable_gvt, bool, 0400,