[Intel-gfx] [PATCH v3 3/3] drm/i915/intel_dsi_vbt: Add support for PMIC MIPI sequences

[Jani Nikula]

On Thu, 13 Dec 2018, Hans de Goede <hdegoede at redhat.com> wrote:
> Add support for PMIC MIPI sequences using the new
> intel_soc_pmic_exec_mipi_pmic_seq_element function.
>
> This fixes the DSI LCD panel not lighting up when not initialized by the
> GOP (because an external monitor was connected) on GPD win and GPD pocket
> devices.
>
> Specifically the LCD panel seems to need GPIO pin 9 on the PMIC to be
> driven high, which is done through a PMIC MIPI sequence. Before this commit
> if the sequence was not executed by the GOP the pin would stay low causing
> the LCD panel to not work. Having the MIPI sequences properly control this
> GPIO should also help save some power when the panel is off.
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi_vbt.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_dsi_vbt.c b/drivers/gpu/drm/i915/intel_dsi_vbt.c
> index f27af47c6e49..6a2ed1ca72e0 100644
> --- a/drivers/gpu/drm/i915/intel_dsi_vbt.c
> +++ b/drivers/gpu/drm/i915/intel_dsi_vbt.c
> @@ -29,6 +29,7 @@
>  #include <drm/drm_edid.h>
>  #include <drm/i915_drm.h>
>  #include <linux/gpio/consumer.h>
> +#include <linux/mfd/intel_soc_pmic.h>
>  #include <linux/slab.h>
>  #include <video/mipi_display.h>
>  #include <asm/intel-mid.h>
> @@ -371,7 +372,11 @@ static const u8 *mipi_exec_spi(struct intel_dsi *intel_dsi, const u8 *data)
>  
>  static const u8 *mipi_exec_pmic(struct intel_dsi *intel_dsi, const u8 *data)
>  {
> +#ifdef CONFIG_PMIC_OPREGION
> +	intel_soc_pmic_exec_mipi_pmic_seq_element(data);
> +#else
>  	DRM_DEBUG_KMS("Skipping PMIC element execution\n");
> +#endif

Please check the return value, and log with DRM_DEBUG_KMS or
DRM_ERROR. With the dummy implementation of
intel_soc_pmic_exec_mipi_pmic_seq_element() returning e.g. -ENODEV this
would also cover the CONFIG_PMIC_OPREGION=n case.

BR,
Jani.

>  
>  	return data + 15;
>  }

-- 
Jani Nikula, Intel Open Source Graphics Center