[Intel-gfx] [PATCH 5/6] drm/i915: parse backlight modulation frequency from the BIOS VBT

[Rodrigo Vivi]

Hi Jani,

On Mon, Dec 2, 2013 at 11:26 AM, Rodrigo Vivi <rodrigo.vivi at gmail.com> wrote:
> From: Jani Nikula <jani.nikula at intel.com>
>
> We don't actually do anything with the information yet, but parse and
> log what's in the VBT.
>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at gmail.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h   |  5 +++++
>  drivers/gpu/drm/i915/intel_bios.c | 29 +++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_bios.h | 16 ++++++++++++++++
>  3 files changed, 50 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 780f815..687eee2 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1185,6 +1185,11 @@ struct intel_vbt_data {
>         int edp_bpp;
>         struct edp_power_seq edp_pps;
>
> +       struct {
> +               u16 pwm_freq_hz;
> +               bool active_low_pwm;
> +       } backlight;
> +
>         /* MIPI DSI */
>         struct {
>                 u16 panel_id;
> diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
> index e4fba39..720ce55 100644
> --- a/drivers/gpu/drm/i915/intel_bios.c
> +++ b/drivers/gpu/drm/i915/intel_bios.c
> @@ -281,6 +281,34 @@ parse_lfp_panel_data(struct drm_i915_private *dev_priv,
>         }
>  }
>
> +static void
> +parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
> +{
> +       const struct bdb_lfp_backlight_data *backlight_data;
> +       const struct bdb_lfp_backlight_data_entry *entry;
> +
> +       backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
> +       if (!backlight_data)
> +               return;
> +
> +       if (backlight_data->entry_size != sizeof(backlight_data->data[0])) {
> +               DRM_DEBUG_KMS("Unsupported backlight data entry size %u\n",
> +                             backlight_data->entry_size);
> +               return;
> +       }
> +
> +       entry = &backlight_data->data[panel_type];
> +
> +       dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz;
> +       dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm;
> +       DRM_DEBUG_KMS("VBT backlight PWM modulation frequency %u Hz, "
> +                     "active %s, min brightness %u, level %u\n",
> +                     dev_priv->vbt.backlight.pwm_freq_hz,
> +                     dev_priv->vbt.backlight.active_low_pwm ? "low" : "high",
> +                     entry->min_brightness,
> +                     backlight_data->level[panel_type]);
> +}
> +
>  /* Try to find sdvo panel data */
>  static void
>  parse_sdvo_panel_data(struct drm_i915_private *dev_priv,
> @@ -894,6 +922,7 @@ intel_parse_bios(struct drm_device *dev)
>         parse_general_features(dev_priv, bdb);
>         parse_general_definitions(dev_priv, bdb);
>         parse_lfp_panel_data(dev_priv, bdb);
> +       parse_lfp_backlight(dev_priv, bdb);
>         parse_sdvo_panel_data(dev_priv, bdb);
>         parse_sdvo_device_mapping(dev_priv, bdb);
>         parse_device_mapping(dev_priv, bdb);
> diff --git a/drivers/gpu/drm/i915/intel_bios.h b/drivers/gpu/drm/i915/intel_bios.h
> index 81ed58c..282de5e 100644
> --- a/drivers/gpu/drm/i915/intel_bios.h
> +++ b/drivers/gpu/drm/i915/intel_bios.h
> @@ -373,6 +373,22 @@ struct bdb_lvds_lfp_data {
>         struct bdb_lvds_lfp_data_entry data[16];
>  } __packed;
>
> +struct bdb_lfp_backlight_data_entry {
> +       u8 type:2;
> +       u8 active_low_pwm:1;

I'd prefer inverted_polarity for this bit.

> +       u8 obsolete1:5;
> +       u16 pwm_freq_hz;
> +       u8 min_brightness;
> +       u8 obsolete2;
> +       u8 obsolete3;
> +} __packed;
> +
> +struct bdb_lfp_backlight_data {
> +       u8 entry_size;
> +       struct bdb_lfp_backlight_data_entry data[16];
> +       u8 level[16];
> +} __packed;
> +
>  struct aimdb_header {
>         char signature[16];
>         char oem_device[20];
> --
> 1.8.3.1
>

with or without my bikeshed,
Reviewed-by: Rodrigo Vivi <rodrigo.vivi at gmail.com>

-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br