Re: [PATCH 09/18] drm/i915/dsi: Make intel_dsi_enable/disable directly exec VBT sequences

[Jani Nikula <jani.nikula@linux.intel.com>]

On Thu, 01 Dec 2016, Hans de Goede <hdegoede@redhat.com> wrote:
> The drm_panel_enable/disable and drm_panel_prepare/unprepare calls are
> not fine grained enough to abstract all the different steps we need to
> take (and VBT sequences we need to exec) properly. So simply remove the
> panel _enable/disable and prepare/unprepare callbacks and instead
> export intel_dsi_exec_vbt_sequence() from intel_dsi_panel_vbt.c
> and call that from intel_dsi_enable/disable().
>
> No functional changes.

No functional changes, but this is quite a big design change between
intel_dsi.c and intel_dsi_panel_vbt.c. Originally the idea was to
separate the dsi core code and the panel specific code, letting one
write a panel driver that was not based on values in VBT. This patch
changes that.

Now I'm not sure if there'll ever be a panel driver not based on VBT,
and perhaps the current drm_panel based interface between two is not
enough in the end, nor prettiest. But after this patch, we might just as
well throw out the drm_panel interface, and refactor the division
between the two files completely. Indeed, if we accept the direction set
in this patch, that refactoring would be the logical next step.

I have not made up my mind about this yet. An alternative would be to
amend the drm_panel interface to achieve the kind of granularity you're
after in the follow-up patches. Indeed, such patches have been sent in
the past.

BR,
Jani.

>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi.c           | 14 +++++++---
>  drivers/gpu/drm/i915/intel_dsi.h           |  3 +++
>  drivers/gpu/drm/i915/intel_dsi_panel_vbt.c | 43 ++----------------------------
>  3 files changed, 15 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 85b748d..cf761e8 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -656,7 +656,10 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder,
>  	/* put device in ready state */
>  	intel_dsi_device_ready(encoder);
>  
> -	drm_panel_prepare(intel_dsi->panel);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_INIT_OTP);
>  
>  	/* Enable port in pre-enable phase itself because as per hw team
>  	 * recommendation, port should be enabled befor plane & pipe */
> @@ -669,7 +672,8 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder,
>  			dpi_send_cmd(intel_dsi, TURN_ON, false, port);
>  		msleep(100);
>  
> -		drm_panel_enable(intel_dsi->panel);
> +		intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);
> +		intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_ON);
>  
>  		intel_dsi_port_enable(encoder);
>  	}
> @@ -732,7 +736,8 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
>  	 * if disable packets are sent before sending shutdown packet then in
>  	 * some next enable sequence send turn on packet error is observed
>  	 */
> -	drm_panel_disable(intel_dsi->panel);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_BACKLIGHT_OFF);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_DISPLAY_OFF);
>  
>  	intel_dsi_clear_device_ready(encoder);
>  
> @@ -746,7 +751,8 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
>  		I915_WRITE(DSPCLK_GATE_D, val);
>  	}
>  
> -	drm_panel_unprepare(intel_dsi->panel);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);
> +	intel_dsi_exec_vbt_sequence(intel_dsi, MIPI_SEQ_POWER_OFF);
>  
>  	msleep(intel_dsi->panel_off_delay);
>  
> diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
> index d567823..5486491 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.h
> +++ b/drivers/gpu/drm/i915/intel_dsi.h
> @@ -132,6 +132,9 @@ static inline struct intel_dsi *enc_to_intel_dsi(struct drm_encoder *encoder)
>  
>  void wait_for_dsi_fifo_empty(struct intel_dsi *intel_dsi, enum port port);
>  
> +void intel_dsi_exec_vbt_sequence(struct intel_dsi *intel_dsi,
> +				 enum mipi_seq seq_id);
> +
>  bool intel_dsi_pll_is_enabled(struct drm_i915_private *dev_priv);
>  int intel_compute_dsi_pll(struct intel_encoder *encoder,
>  			  struct intel_crtc_state *config);
> diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> index b5a02c6..f71f913 100644
> --- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> +++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
> @@ -400,10 +400,9 @@ static const char *sequence_name(enum mipi_seq seq_id)
>  		return "(unknown)";
>  }
>  
> -static void generic_exec_sequence(struct drm_panel *panel, enum mipi_seq seq_id)
> +void intel_dsi_exec_vbt_sequence(struct intel_dsi *intel_dsi,
> +				 enum mipi_seq seq_id)
>  {
> -	struct vbt_panel *vbt_panel = to_vbt_panel(panel);
> -	struct intel_dsi *intel_dsi = vbt_panel->intel_dsi;
>  	struct drm_i915_private *dev_priv = to_i915(intel_dsi->base.base.dev);
>  	const u8 *data;
>  	fn_mipi_elem_exec mipi_elem_exec;
> @@ -467,40 +466,6 @@ static void generic_exec_sequence(struct drm_panel *panel, enum mipi_seq seq_id)
>  	}
>  }
>  
> -static int vbt_panel_prepare(struct drm_panel *panel)
> -{
> -	generic_exec_sequence(panel, MIPI_SEQ_ASSERT_RESET);
> -	generic_exec_sequence(panel, MIPI_SEQ_POWER_ON);
> -	generic_exec_sequence(panel, MIPI_SEQ_DEASSERT_RESET);
> -	generic_exec_sequence(panel, MIPI_SEQ_INIT_OTP);
> -
> -	return 0;
> -}
> -
> -static int vbt_panel_unprepare(struct drm_panel *panel)
> -{
> -	generic_exec_sequence(panel, MIPI_SEQ_ASSERT_RESET);
> -	generic_exec_sequence(panel, MIPI_SEQ_POWER_OFF);
> -
> -	return 0;
> -}
> -
> -static int vbt_panel_enable(struct drm_panel *panel)
> -{
> -	generic_exec_sequence(panel, MIPI_SEQ_DISPLAY_ON);
> -	generic_exec_sequence(panel, MIPI_SEQ_BACKLIGHT_ON);
> -
> -	return 0;
> -}
> -
> -static int vbt_panel_disable(struct drm_panel *panel)
> -{
> -	generic_exec_sequence(panel, MIPI_SEQ_BACKLIGHT_OFF);
> -	generic_exec_sequence(panel, MIPI_SEQ_DISPLAY_OFF);
> -
> -	return 0;
> -}
> -
>  static int vbt_panel_get_modes(struct drm_panel *panel)
>  {
>  	struct vbt_panel *vbt_panel = to_vbt_panel(panel);
> @@ -524,10 +489,6 @@ static int vbt_panel_get_modes(struct drm_panel *panel)
>  }
>  
>  static const struct drm_panel_funcs vbt_panel_funcs = {
> -	.disable = vbt_panel_disable,
> -	.unprepare = vbt_panel_unprepare,
> -	.prepare = vbt_panel_prepare,
> -	.enable = vbt_panel_enable,
>  	.get_modes = vbt_panel_get_modes,
>  };

-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx