Add basic support for multi-channel PCM audio, with fixed speaker mappings. This has been tested with an AV receiver, and appears to work for low sample rates up to 8 channels.
It should be noted that multi-channel mode using the IEC958 alsa-lib conversion plugin requires correct AES channel status for the AV receiver to recognise the stream, especially the sample rate bits. "Not identified" does not work there.
Signed-off-by: Russell King rmk+kernel@arm.linux.org.uk --- drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c | 59 +++++++++++++++++++++++++++++- 1 file changed, 57 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c b/drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c index 125b81306254..3a8f32e04b63 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c +++ b/drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c @@ -62,9 +62,14 @@ enum { HDMI_AHB_DMA_CONF0_INCR4 = 0, HDMI_AHB_DMA_CONF0_BURST_MODE = BIT(0), HDMI_AHB_DMA_MASK_DONE = BIT(7), + HDMI_REVISION_ID = 0x0001, HDMI_IH_AHBDMAAUD_STAT0 = 0x0109, HDMI_IH_MUTE_AHBDMAAUD_STAT0 = 0x0189, + HDMI_FC_AUDICONF2 = 0x1027, + HDMI_FC_AUDSCONF = 0x1063, + HDMI_FC_AUDSCONF_LAYOUT1 = 1 << 0, + HDMI_FC_AUDSCONF_LAYOUT0 = 0 << 0, HDMI_AHB_DMA_CONF0 = 0x3600, HDMI_AHB_DMA_START = 0x3601, HDMI_AHB_DMA_STOP = 0x3602, @@ -77,6 +82,44 @@ enum { HDMI_AHB_DMA_BUFFPOL = 0x361a, };
+struct dw_hdmi_channel_conf { + u8 conf1; + u8 ca; +}; + +/* + * The default mapping of ALSA channels to HDMI channels and speaker + * allocation bits. Note that we can't do channel remapping here - + * channels must be in the same order. + * + * Mappings for alsa-lib pcm/surround*.conf files: + * + * Front Sur4.0 Sur4.1 Sur5.0 Sur5.1 Sur7.1 + * Channels 2 4 6 6 6 8 + * + * Our mapping from ALSA channel to CEA686D speaker name and HDMI channel: + * + * Number of ALSA channels + * ALSA Channel 2 3 4 5 6 7 8 + * 0 FL:0 = = = = = = + * 1 FR:1 = = = = = = + * 2 FC:3 RL:4 LFE:2 = = = + * 3 RR:5 RL:4 FC:3 = = + * 4 RR:5 RL:4 = = + * 5 RR:5 = = + * 6 RC:6 = + * 7 RLC/FRC RLC/FRC + */ +static struct dw_hdmi_channel_conf default_hdmi_channel_config[7] = { + { 0x03, 0x00 }, /* FL,FR */ + { 0x0b, 0x02 }, /* FL,FR,FC */ + { 0x33, 0x08 }, /* FL,FR,RL,RR */ + { 0x37, 0x09 }, /* FL,FR,LFE,RL,RR */ + { 0x3f, 0x0b }, /* FL,FR,LFE,FC,RL,RR */ + { 0x7f, 0x0f }, /* FL,FR,LFE,FC,RL,RR,RC */ + { 0xff, 0x13 }, /* FL,FR,LFE,FC,RL,RR,[FR]RC,[FR]LC */ +}; + struct snd_dw_hdmi { struct snd_card *card; struct snd_pcm *pcm; @@ -352,7 +395,7 @@ static int dw_hdmi_prepare(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; struct snd_dw_hdmi *dw = substream->private_data; - u8 threshold, conf0, conf1; + u8 threshold, conf0, conf1, layout, ca;
/* Setup as per 3.0.5 FSL 4.1.0 BSP */ switch (dw->revision) { @@ -380,11 +423,23 @@ static int dw_hdmi_prepare(struct snd_pcm_substream *substream) runtime->hw.fifo_size = threshold * 32;
conf0 |= HDMI_AHB_DMA_CONF0_EN_HLOCK; - conf1 = (1 << runtime->channels) - 1; + conf1 = default_hdmi_channel_config[runtime->channels - 2].conf1; + ca = default_hdmi_channel_config[runtime->channels - 2].ca; + + /* + * For >2 channel PCM audio, we need to select layout 1 + * and set an appropriate channel map. + */ + if (runtime->channels > 2) + layout = HDMI_FC_AUDSCONF_LAYOUT1; + else + layout = HDMI_FC_AUDSCONF_LAYOUT0;
writeb_relaxed(threshold, dw->data.base + HDMI_AHB_DMA_THRSLD); writeb_relaxed(conf0, dw->data.base + HDMI_AHB_DMA_CONF0); writeb_relaxed(conf1, dw->data.base + HDMI_AHB_DMA_CONF1); + writeb_relaxed(layout, dw->data.base + HDMI_FC_AUDSCONF); + writeb_relaxed(ca, dw->data.base + HDMI_FC_AUDICONF2);
switch (runtime->format) { case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE: