[Intel-gfx] [PATCH v5 5/5] drm/i915: Add lspcon resume function

[Imre Deak]

On pe, 2016-10-14 at 14:54 +0530, Shashank Sharma wrote:
> As per the software design, we are driving lspcon in
> PCON mode. But while resuming from suspend, lspcon can go
> in LS mode (which is its default operating mode on power on)
> 
> This patch adds a resume function for lspcon, which makes sure
> its operating in PCON mode, post resume.
> 
> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c     |  2 ++
>  drivers/gpu/drm/i915/intel_drv.h    |  1 +
>  drivers/gpu/drm/i915/intel_lspcon.c | 38 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 41 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index e9b3bfc..d87281d 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1574,6 +1574,8 @@ static int i915_drm_resume(struct drm_device *dev)
>  		dev_priv->display.hpd_irq_setup(dev_priv);
>  	spin_unlock_irq(&dev_priv->irq_lock);
>  
> +	lspcon_resume(dev);
> +

This should go to the encoder reset hook.

>  	intel_dp_mst_resume(dev);
>  
>  	intel_display_resume(dev);
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 27837b0..e8760a4 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1850,4 +1850,5 @@ void intel_color_load_luts(struct drm_crtc_state *crtc_state);
>  
>  /* intel_lspcon.c */
>  bool lspcon_init(struct intel_digital_port *intel_dig_port);
> +void lspcon_resume(struct drm_device *dev);
>  #endif /* __INTEL_DRV_H__ */
> diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
> index aa74b1f..ba660ecb 100644
> --- a/drivers/gpu/drm/i915/intel_lspcon.c
> +++ b/drivers/gpu/drm/i915/intel_lspcon.c
> @@ -27,6 +27,29 @@
>  #include 
>  #include "intel_drv.h"
>  
> +/*
> + * This function assumes only one LSPCON port on the device,
> + * and returns the first active LSPCON port.
> + */
> +static struct intel_lspcon *find_active_lspcon(struct drm_device *dev)
> +{
> +	struct intel_lspcon *lspcon = NULL;
> +	struct intel_encoder *intel_encoder;
> +
> +	for_each_intel_encoder(dev, intel_encoder) {
> +		struct intel_digital_port *intel_dig_port;
> +
> +		intel_dig_port = enc_to_dig_port(&intel_encoder->base);
> +		lspcon = &intel_dig_port->lspcon;
> +		if (lspcon->active) {
> +			DRM_DEBUG_KMS("LSPCON active : port %c\n",
> +					port_name(intel_dig_port->port));
> +			break;
> +		}
> +	}
> +	return lspcon;
> +}
> +
>  enum drm_lspcon_mode lspcon_get_current_mode(struct intel_lspcon *lspcon)
>  {
>  	enum drm_lspcon_mode current_mode = DRM_LSPCON_MODE_INVALID;
> @@ -89,6 +112,21 @@ static bool lspcon_probe(struct intel_lspcon *lspcon)
>  	return true;
>  }
>  
> +void lspcon_resume(struct drm_device *dev)
> +{
> +	if (IS_GEN9(dev)) {
> +		struct intel_lspcon *lspcon = find_active_lspcon(dev);
> +
> +		if (lspcon) {
> +			if (lspcon_change_mode(lspcon, DRM_LSPCON_MODE_PCON,
> +						true))
> +				DRM_ERROR("LSPCON resume failed\n");
> +			else
> +				DRM_DEBUG_KMS("LSPCON resume success\n");
> +		}
> +	}
> +}

Nitpick: you could reduce indentation above by using early returns.


> +
>  bool lspcon_init(struct intel_digital_port *intel_dig_port)
>  {
>  	struct intel_dp *dp = &intel_dig_port->dp;