Re: [PATCH 01/11] drm: bridge/dw_hdmi: add audio sample channel status setting

[Yang Kuankuan <ykk@rock-chips.com>]

[-- Attachment #1.1: Type: text/plain, Size: 4087 bytes --]


On 01/31/2015 05:59 AM, Russell King - ARM Linux wrote:
> On Fri, Jan 30, 2015 at 06:19:46AM -0500, Yakir Yang wrote:
>> When transmitting IEC60985 linear PCM audio, we configure the
>> Aduio Sample Channel Status information of all the channel
>> status bits in the IEC60958 frame.
> It appears that the iMX6 version of the DW-HDMI IP does not have these
> registers.  These registers are quite possibly only available on IPs
> which do not have the built-in AHB DMA, since the channel status bits
> are encoded into the samples in memory.
>
> Can you report what identifying information your version of this IP
> outputs please?  On iMX6, I get:
>
> dwhdmi-imx 120000.hdmi: Detected HDMI controller 0x13:0xa:0xa0:0xc1
>
> for iMX6Quad, and for iMX6Solo:
>
> dwhdmi-imx 120000.hdmi: Detected HDMI controller 0x13:0x1a:0xa0:0xc1
>
> Thanks.
>
> Further comments below.

Here are the IP version on rk3288:
     dwhdmi-rockchip ff980000.hdmi: Detected HDMI controller 
0x20:0xa:0xa0:0xc1

attache the register description:

*5.2.5.50 fc_audschnls0 to fc_audschnls8*
     When transmitting IEC60958 linear PCM audio, this registers allow 
to configure the channel status
     information of all the channel status bits in the IEC60958 frame. 
For the moment this configuration is only
     used when the I2S audio interface, General Purpose Audio (GPA), or 
AHB audio DMA (AHBAUDDMA)
     interface is active (for S/PDIF interface this information comes 
from the stream). Information configured is
     the following:
         IEC Copyright indication
         CGMS-A
         PCM audio mode
         Category code
         Source number
         Channel number for first right sample
         Channel number for second right sample
         Channel number for third right sample
         Channel number for fourth right sample
         Channel number for first left sample
         Channel number for second left sample
         Channel number for third left sample
         Channel number for fourth left sample
         Clock accuracy
         Sampling frequency
         Original sampling frequency
         Word length configuration

Thks for you reply, : )

Best Regards.
>
>> diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c
>> index 423addc..2ded957 100644
>> --- a/drivers/gpu/drm/bridge/dw_hdmi.c
>> +++ b/drivers/gpu/drm/bridge/dw_hdmi.c
>> @@ -204,6 +204,47 @@ static void hdmi_regenerate_n_cts(struct dw_hdmi *hdmi, unsigned int n,
>>   	hdmi_writeb(hdmi, n & 0xff, HDMI_AUD_N1);
>>   }
>>   
>> +static void hdmi_set_schnl(struct dw_hdmi *hdmi)
>> +{
>> +	u8 aud_schnl_samplerate;
>> +
>> +	switch (hdmi->sample_rate) {
>> +	case 32000:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_32K;
>> +		break;
>> +	case 44100:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_44K1;
>> +		break;
>> +	case 48000:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_48K;
>> +		break;
>> +	case 88200:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_88K2;
>> +		break;
>> +	case 96000:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_96K;
>> +		break;
>> +	case 176400:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_176K4;
>> +		break;
>> +	case 192000:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_192K;
>> +		break;
>> +	case 768000:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_768K;
>> +		break;
>> +	default:
>> +		aud_schnl_samplerate = HDMI_FC_AUDSCHNLS7_SMPRATE_44K1;
>> +		break;
>> +	}
>> +
>> +	/* set channel status register */
>> +	hdmi_modb(hdmi, aud_schnl_samplerate,
>> +		  HDMI_FC_AUDSCHNLS7_SMPRATE_MASK, HDMI_FC_AUDSCHNLS7);
>> +	hdmi_writeb(hdmi, ((~aud_schnl_samplerate) << 4) | 0x2,
>> +		    HDMI_FC_AUDSCHNLS8);
>> +}
>> +
> You should not split patches up like this - this patch introduces a new
> static function, which is never used until a subsequent patch.  If this
> patch were to be merged, it would introduce a new build warning.
>
> Please ensure that each patch in the series can be applied in sequence
> without causing a regression.
>
> Thanks.
>


[-- Attachment #1.2: Type: text/html, Size: 5091 bytes --]

[-- Attachment #2: Type: text/plain, Size: 159 bytes --]

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel