Re: [PATCH v2 4/5] drm: dw-hdmi: use cec_notifier_conn_(un)register

[Hans Verkuil <hverkuil-cisco@xs4all.nl>]

On 7/1/19 4:59 PM, Dariusz Marcinkiewicz wrote:
> Use the new cec_notifier_conn_(un)register() functions to
> (un)register the notifier for the HDMI connector, and fill in
> the cec_connector_info.
> 
> Changes since v1:
> 	Add memory barrier to make sure that the notifier
> 	becomes visible to the irq thread once it is fully
> 	constructed.
> 
> Signed-off-by: Dariusz Marcinkiewicz <darekm@google.com>
> ---
>  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 37 +++++++++++++++--------
>  1 file changed, 24 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index ab7968c8f6a29..c0f4eb3c12b18 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -2118,6 +2118,8 @@ static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
>  	struct dw_hdmi *hdmi = bridge->driver_private;
>  	struct drm_encoder *encoder = bridge->encoder;
>  	struct drm_connector *connector = &hdmi->connector;
> +	struct cec_connector_info conn_info;
> +	struct cec_notifier *notifier;
>  
>  	connector->interlace_allowed = 1;
>  	connector->polled = DRM_CONNECTOR_POLL_HPD;
> @@ -2129,6 +2131,18 @@ static int dw_hdmi_bridge_attach(struct drm_bridge *bridge)
>  
>  	drm_connector_attach_encoder(connector, encoder);
>  
> +	cec_fill_conn_info_from_drm(&conn_info, connector);
> +
> +	notifier = cec_notifier_conn_register(hdmi->dev, NULL, &conn_info);
> +	if (!notifier)
> +		return -ENOMEM;
> +	/*
> +	 * Make sure that dw_hdmi_irq thread does see the notifier
> +	 * when it fully constructed.
> +	 */
> +	smp_wmb();
> +	hdmi->cec_notifier = notifier;
> +
>  	return 0;
>  }
>  
> @@ -2295,9 +2309,15 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
>  				       phy_stat & HDMI_PHY_HPD,
>  				       phy_stat & HDMI_PHY_RX_SENSE);
>  
> -		if ((phy_stat & (HDMI_PHY_RX_SENSE | HDMI_PHY_HPD)) == 0)
> -			cec_notifier_set_phys_addr(hdmi->cec_notifier,
> -						   CEC_PHYS_ADDR_INVALID);
> +		if ((phy_stat & (HDMI_PHY_RX_SENSE | HDMI_PHY_HPD)) == 0) {
> +			struct cec_notifier *notifer;
> +
> +			notifer = READ_ONCE(hdmi->cec_notifier);
> +			if (notifer)
> +				cec_notifier_set_phys_addr(
> +						notifer,
> +						CEC_PHYS_ADDR_INVALID);

Please replace with cec_notifier_phys_addr_invalidate().

> +		}
>  	}
>  
>  	if (intr_stat & HDMI_IH_PHY_STAT0_HPD) {
> @@ -2600,12 +2620,6 @@ __dw_hdmi_probe(struct platform_device *pdev,
>  	if (ret)
>  		goto err_iahb;
>  
> -	hdmi->cec_notifier = cec_notifier_get(dev);
> -	if (!hdmi->cec_notifier) {
> -		ret = -ENOMEM;
> -		goto err_iahb;
> -	}
> -
>  	/*
>  	 * To prevent overflows in HDMI_IH_FC_STAT2, set the clk regenerator
>  	 * N and cts values before enabling phy
> @@ -2693,9 +2707,6 @@ __dw_hdmi_probe(struct platform_device *pdev,
>  		hdmi->ddc = NULL;
>  	}
>  
> -	if (hdmi->cec_notifier)
> -		cec_notifier_put(hdmi->cec_notifier);
> -
>  	clk_disable_unprepare(hdmi->iahb_clk);
>  	if (hdmi->cec_clk)
>  		clk_disable_unprepare(hdmi->cec_clk);
> @@ -2718,7 +2729,7 @@ static void __dw_hdmi_remove(struct dw_hdmi *hdmi)
>  	hdmi_writeb(hdmi, ~0, HDMI_IH_MUTE_PHY_STAT0);
>  
>  	if (hdmi->cec_notifier)
> -		cec_notifier_put(hdmi->cec_notifier);
> +		cec_notifier_conn_unregister(hdmi->cec_notifier);

No need for the 'if', cec_notifier_conn_unregister() already checks for a NULL
notifier.

Regards,

	Hans

>  
>  	clk_disable_unprepare(hdmi->iahb_clk);
>  	clk_disable_unprepare(hdmi->isfr_clk);
>