Re: [PATCH v7 1/5] drm/i915: Pass port to intel_panel_bl_funcs.get()

From: Jani Nikula
Date: Fri Jan 15 2021 - 08:49:15 EST


On Thu, 14 Jan 2021, Lyude Paul <lyude@xxxxxxxxxx> wrote:
> In the next commit where we split PWM related backlight functions from
> higher-level backlight functions, we'll want to be able to retrieve the
> backlight level for the current display panel from the
> intel_panel_bl_funcs->setup() function using pwm_funcs->get(). Since
> intel_panel_bl_funcs->setup() is called before we've fully read in the
> current hardware state into our atomic state, we can't grab atomic
> modesetting locks safely anyway in intel_panel_bl_funcs->setup(), and some
> PWM backlight functions (vlv_get_backlight() in particular) require knowing
> the currently used pipe we need to be able to discern the current display
> pipe through other means. Luckily, we're already passing the current
> display pipe to intel_panel_bl_funcs->setup() so all we have to do in order
> to achieve this is pass down that parameter to intel_panel_bl_funcs->get().
>
> So, fix this by accepting an additional pipe parameter in
> intel_panel_bl_funcs->get(), and leave figuring out the current display
> pipe up to the caller.
>
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>

Much neater than anything I suggested!

Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>

> ---
> .../drm/i915/display/intel_display_types.h | 2 +-
> .../drm/i915/display/intel_dp_aux_backlight.c | 4 +-
> .../i915/display/intel_dsi_dcs_backlight.c | 2 +-
> drivers/gpu/drm/i915/display/intel_panel.c | 40 ++++++++-----------
> 4 files changed, 21 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 585bb1edea04..b1f4ec144207 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -228,7 +228,7 @@ struct intel_encoder {
> struct intel_panel_bl_funcs {
> /* Connector and platform specific backlight functions */
> int (*setup)(struct intel_connector *connector, enum pipe pipe);
> - u32 (*get)(struct intel_connector *connector);
> + u32 (*get)(struct intel_connector *connector, enum pipe pipe);
> void (*set)(const struct drm_connector_state *conn_state, u32 level);
> void (*disable)(const struct drm_connector_state *conn_state, u32 level);
> void (*enable)(const struct intel_crtc_state *crtc_state,
> 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 9775f33d1aac..de764dae1e66 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> @@ -128,7 +128,7 @@ static bool intel_dp_aux_vesa_backlight_dpcd_mode(struct intel_connector *connec
> * Read the current backlight value from DPCD register(s) based
> * on if 8-bit(MSB) or 16-bit(MSB and LSB) values are supported
> */
> -static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector)
> +static u32 intel_dp_aux_vesa_get_backlight(struct intel_connector *connector, enum pipe unused)
> {
> struct intel_dp *intel_dp = intel_attached_dp(connector);
> struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> @@ -381,7 +381,7 @@ static int intel_dp_aux_vesa_setup_backlight(struct intel_connector *connector,
> return -ENODEV;
>
> panel->backlight.min = 0;
> - panel->backlight.level = intel_dp_aux_vesa_get_backlight(connector);
> + panel->backlight.level = intel_dp_aux_vesa_get_backlight(connector, pipe);
> panel->backlight.enabled = intel_dp_aux_vesa_backlight_dpcd_mode(connector) &&
> panel->backlight.level != 0;
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
> index 88628764956d..584c14c4cbd0 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_dcs_backlight.c
> @@ -43,7 +43,7 @@
>
> #define PANEL_PWM_MAX_VALUE 0xFF
>
> -static u32 dcs_get_backlight(struct intel_connector *connector)
> +static u32 dcs_get_backlight(struct intel_connector *connector, enum pipe unused)
> {
> struct intel_encoder *encoder = intel_attached_encoder(connector);
> struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
> diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c
> index 7a4239d1c241..7587aaefc7a0 100644
> --- a/drivers/gpu/drm/i915/display/intel_panel.c
> +++ b/drivers/gpu/drm/i915/display/intel_panel.c
> @@ -530,21 +530,21 @@ static u32 intel_panel_compute_brightness(struct intel_connector *connector,
> return val;
> }
>
> -static u32 lpt_get_backlight(struct intel_connector *connector)
> +static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
> {
> struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>
> return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
> }
>
> -static u32 pch_get_backlight(struct intel_connector *connector)
> +static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
> {
> struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
>
> return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> }
>
> -static u32 i9xx_get_backlight(struct intel_connector *connector)
> +static u32 i9xx_get_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;
> @@ -564,23 +564,17 @@ static u32 i9xx_get_backlight(struct intel_connector *connector)
> return val;
> }
>
> -static u32 _vlv_get_backlight(struct drm_i915_private *dev_priv, enum pipe pipe)
> +static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
> {
> + struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
> return 0;
>
> return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
> }
>
> -static u32 vlv_get_backlight(struct intel_connector *connector)
> -{
> - struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> - enum pipe pipe = intel_connector_get_pipe(connector);
> -
> - return _vlv_get_backlight(dev_priv, pipe);
> -}
> -
> -static u32 bxt_get_backlight(struct intel_connector *connector)
> +static u32 bxt_get_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;
> @@ -589,7 +583,7 @@ static u32 bxt_get_backlight(struct intel_connector *connector)
> BXT_BLC_PWM_DUTY(panel->backlight.controller));
> }
>
> -static u32 ext_pwm_get_backlight(struct intel_connector *connector)
> +static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
> {
> struct intel_panel *panel = &connector->panel;
> struct pwm_state state;
> @@ -1233,7 +1227,7 @@ static u32 intel_panel_get_backlight(struct intel_connector *connector)
> mutex_lock(&dev_priv->backlight_lock);
>
> if (panel->backlight.enabled) {
> - val = panel->backlight.funcs->get(connector);
> + val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
> val = intel_panel_compute_brightness(connector, val);
> }
>
> @@ -1646,9 +1640,9 @@ static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unus
> !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
> (cpu_ctl2 & BLM_PWM_ENABLE);
> if (cpu_mode)
> - val = pch_get_backlight(connector);
> + val = pch_get_backlight(connector, unused);
> else
> - val = lpt_get_backlight(connector);
> + val = lpt_get_backlight(connector, unused);
>
> if (cpu_mode) {
> drm_dbg_kms(&dev_priv->drm,
> @@ -1690,7 +1684,7 @@ static int pch_setup_backlight(struct intel_connector *connector, enum pipe unus
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = pch_get_backlight(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);
> @@ -1731,7 +1725,7 @@ static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unu
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = i9xx_get_backlight(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);
> @@ -1765,7 +1759,7 @@ static int i965_setup_backlight(struct intel_connector *connector, enum pipe unu
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = i9xx_get_backlight(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);
> @@ -1798,7 +1792,7 @@ static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = _vlv_get_backlight(dev_priv, pipe);
> + val = vlv_get_backlight(connector, pipe);
> val = intel_panel_compute_brightness(connector, val);
> panel->backlight.level = clamp(val, panel->backlight.min,
> panel->backlight.max);
> @@ -1840,7 +1834,7 @@ bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = bxt_get_backlight(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);
> @@ -1880,7 +1874,7 @@ cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
>
> panel->backlight.min = get_backlight_min_vbt(connector);
>
> - val = bxt_get_backlight(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);

--
Jani Nikula, Intel Open Source Graphics Center