[v2,28/28] drm/i2c: tda998x: add a CODEC interface

The TDA998x chips may get audio input from I2S or S/PDIF and this input
is defined by the audio subsystem.

In the other way, the audio subsystem may need to know if audio output
may be done through the HDMI connector.

This patch adds a CODEC interface for exchanges between the HDMI transmitter and the audio subsystem.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
---
 drivers/gpu/drm/i2c/tda998x_drv.c  | 70 ++++++++++++++++++++--
 1 file changed, 65 insertions(+), 5 deletions(-)

At Thu, 9 Jan 2014 12:08:03 +0100,
Jean-Francois Moine wrote:
> 
> The TDA998x chips may get audio input from I2S or S/PDIF and this input
> is defined by the audio subsystem.
> 
> In the other way, the audio subsystem may need to know if audio output
> may be done through the HDMI connector.
> 
> This patch adds a CODEC interface for exchanges between the HDMI transmitter and the audio subsystem.

So this is a kind of hotplug event to be notified to the audio stack,
right?  This reminds me of the discussion I had with Dave and Daniel
at the previous LCE/KS.  Even for PCs with HD-audio, a similar thin
layer would be preferred instead of the current indirect way via ELD,
hardware IRQ and HD-audio unsolicited events.

I guess in the end we'd need some common layer, e.g. a platform
device, to provide a graphics/audio communication like hotplug
notification, EDID and port assignment sharing, refcounting for PM,
etc.

That said, my comment isn't about your patch (which looks simple
enough), but just for future works to chat for now :)


thanks,

Takashi

> 
> Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
> ---
>  drivers/gpu/drm/i2c/tda998x_drv.c  | 70 ++++++++++++++++++++--
>  1 file changed, 65 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c
> index 67d7450..5a186e4 100644
> --- a/drivers/gpu/drm/i2c/tda998x_drv.c
> +++ b/drivers/gpu/drm/i2c/tda998x_drv.c
> @@ -42,7 +42,8 @@ struct tda998x_priv {
>  	u8 vip_cntrl_1;
>  	u8 vip_cntrl_2;
>  
> -	u8 audio_type;		/* audio type */
> +	u8 audio_type;		/* audio type and 'active' flag */
> +#define AUDIO_ACTIVE 0x80
>  	u8 audio_frame[6];
>  	u32 audio_port;
>  
> @@ -50,6 +51,9 @@ struct tda998x_priv {
>  	wait_queue_head_t wq_edid;
>  	volatile int wq_edid_wait;
>  	struct drm_encoder *encoder;
> +
> +	struct snd_soc_codec *codec;
> +	void (*event)(struct snd_soc_codec *codec, int activate);
>  };
>  
>  #define to_tda998x_priv(x)  ((struct tda998x_priv *)to_encoder_slave(x)->slave_priv)
> @@ -731,14 +735,14 @@ tda998x_configure_audio(struct tda998x_priv *priv,
>  
>  	/* Set audio input source */
>  	switch (priv->audio_type) {
> -	case AFMT_SPDIF:
> +	case AFMT_SPDIF | AUDIO_ACTIVE:
>  		reg_write(priv, REG_MUX_AP, MUX_AP_SELECT_SPDIF);
>  		clksel_aip = AIP_CLKSEL_AIP(SEL_AIP_SPDIF);
>  		clksel_fs = AIP_CLKSEL_FS(CTSREF_FS64SPDIF);
>  		cts_n = CTS_N_M(3) | CTS_N_K(3);
>  		break;
>  
> -	case AFMT_I2S:
> +	case AFMT_I2S | AUDIO_ACTIVE:
>  		reg_write(priv, REG_MUX_AP, MUX_AP_SELECT_I2S);
>  		clksel_aip = AIP_CLKSEL_AIP(SEL_AIP_I2S);
>  		clksel_fs = AIP_CLKSEL_FS(CTSREF_ACLK);
> @@ -813,6 +817,58 @@ tda998x_configure_audio(struct tda998x_priv *priv,
>  	tda998x_write_aif(priv);
>  }
>  
> +/* tda998x codec interface */
> +void tda998x_audio_register(struct i2c_client *client,
> +			struct snd_soc_codec *codec,
> +			void (*event)(struct snd_soc_codec *codec, int activate))
> +{
> +	struct tda998x_priv *priv = i2c_get_clientdata(client);
> +
> +	/* memorize the codec and the callback function */
> +	priv->codec = codec;
> +	priv->event = event;
> +}
> +EXPORT_SYMBOL_GPL(tda998x_audio_register);
> +
> +void tda998x_audio_update(struct i2c_client *client,
> +			int type,
> +			u32 port)
> +{
> +	struct tda998x_priv *priv = i2c_get_clientdata(client);
> +
> +	/* if the audio output is active, it may be a second start or a stop */
> +	if (type == 0 || (priv->audio_type & AUDIO_ACTIVE)) {
> +		if (type == 0) {
> +			priv->audio_type &= ~AUDIO_ACTIVE;	/* stop */
> +			reg_write(priv, REG_ENA_AP, 0);
> +		}
> +		return;
> +	}
> +
> +	priv->audio_port = port;
> +
> +	/* don't restart audio if same input type */
> +	if (type == priv->audio_type) {
> +		priv->audio_type |= AUDIO_ACTIVE;
> +		reg_write(priv, REG_ENA_AP, priv->audio_port);
> +		return;
> +	}
> +
> +	priv->audio_type = type | AUDIO_ACTIVE;
> +
> +	tda998x_configure_audio(priv, &priv->encoder->crtc->hwmode);
> +}
> +EXPORT_SYMBOL_GPL(tda998x_audio_update);
> +
> +/* send an audio event to the tda codec */
> +static void send_audio_event(struct tda998x_priv *priv,
> +				int event)
> +{
> +	if (!priv->event)
> +		return;
> +	priv->event(priv->codec, event);
> +}
> +
>  /* DRM encoder functions */
>  
>  /* this function is not called when no info->platform (DT support) */
> @@ -840,7 +896,7 @@ tda998x_encoder_set_config(struct drm_encoder *encoder, void *params)
>  
>  	if (p->audio_cfg) {
>  		priv->audio_port = p->audio_cfg;
> -		priv->audio_type = p->audio_format;
> +		priv->audio_type = p->audio_format | AUDIO_ACTIVE;
>  	}
>  }
>  
> @@ -1105,9 +1161,10 @@ tda998x_encoder_mode_set(struct drm_encoder *encoder,
>  
>  		tda998x_write_avi(priv, mode);
>  
> -		if (priv->audio_type)
> +		if (priv->audio_type & AUDIO_ACTIVE)
>  			tda998x_configure_audio(priv, mode);
>  	}
> +	send_audio_event(priv, priv->is_hdmi_sink);
>  
>  	/* must be last register set: */
>  	reg_write(priv, REG_TBG_CNTRL_0, 0);
> @@ -1263,6 +1320,7 @@ tda998x_encoder_get_modes(struct drm_encoder *encoder,
>  		drm_mode_connector_update_edid_property(connector, edid);
>  		n = drm_add_edid_modes(connector, edid);
>  		priv->is_hdmi_sink = drm_detect_hdmi_monitor(edid);
> +		send_audio_event(priv, priv->is_hdmi_sink);
>  		kfree(edid);
>  	}
>  
> @@ -1349,6 +1407,8 @@ tda998x_encoder_init(struct i2c_client *client,
>  	if (!priv)
>  		return -ENOMEM;
>  
> +	i2c_set_clientdata(client, priv);
> +
>  	priv->vip_cntrl_0 = VIP_CNTRL_0_SWAP_A(2) | VIP_CNTRL_0_SWAP_B(3);
>  	priv->vip_cntrl_1 = VIP_CNTRL_1_SWAP_C(0) | VIP_CNTRL_1_SWAP_D(1);
>  	priv->vip_cntrl_2 = VIP_CNTRL_2_SWAP_E(4) | VIP_CNTRL_2_SWAP_F(5);
> -- 
> Ken ar c'hentañ	|	      ** Breizh ha Linux atav! **
> Jef		|		http://moinejf.free.fr/
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel