ASoC: sunxi: sun4i-spdif: Implement IEC958 control

SPDIF core is capable of sending custom status.

Implement IEC958 control handling.
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20211117194458.2249643-1-jernej.skrabec@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sunxi/sun4i-spdif.c

@@ -21,6 +21,8 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
+#include <linux/spinlock.h>
+#include <sound/asoundef.h>
 #include <sound/dmaengine_pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
@@ -186,6 +188,7 @@ struct sun4i_spdif_dev {
 	struct regmap *regmap;
 	struct snd_dmaengine_dai_dma_data dma_params_tx;
 	const struct sun4i_spdif_quirks *quirks;
+	spinlock_t lock;
 };
 
 static void sun4i_spdif_configure(struct sun4i_spdif_dev *host)
@@ -385,11 +388,122 @@ static int sun4i_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
 	return ret;
 }
 
+static int sun4i_spdif_info(struct snd_kcontrol *kcontrol,
+			    struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+	uinfo->count = 1;
+
+	return 0;
+}
+
+static int sun4i_spdif_get_status_mask(struct snd_kcontrol *kcontrol,
+				       struct snd_ctl_elem_value *ucontrol)
+{
+	u8 *status = ucontrol->value.iec958.status;
+
+	status[0] = 0xff;
+	status[1] = 0xff;
+	status[2] = 0xff;
+	status[3] = 0xff;
+	status[4] = 0xff;
+	status[5] = 0x03;
+
+	return 0;
+}
+
+static int sun4i_spdif_get_status(struct snd_kcontrol *kcontrol,
+				  struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(cpu_dai);
+	u8 *status = ucontrol->value.iec958.status;
+	unsigned long flags;
+	unsigned int reg;
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	regmap_read(host->regmap, SUN4I_SPDIF_TXCHSTA0, &reg);
+
+	status[0] = reg & 0xff;
+	status[1] = (reg >> 8) & 0xff;
+	status[2] = (reg >> 16) & 0xff;
+	status[3] = (reg >> 24) & 0xff;
+
+	regmap_read(host->regmap, SUN4I_SPDIF_TXCHSTA1, &reg);
+
+	status[4] = reg & 0xff;
+	status[5] = (reg >> 8) & 0x3;
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return 0;
+}
+
+static int sun4i_spdif_set_status(struct snd_kcontrol *kcontrol,
+				  struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(cpu_dai);
+	u8 *status = ucontrol->value.iec958.status;
+	unsigned long flags;
+	unsigned int reg;
+	bool chg0, chg1;
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	reg = (u32)status[3] << 24;
+	reg |= (u32)status[2] << 16;
+	reg |= (u32)status[1] << 8;
+	reg |= (u32)status[0];
+
+	regmap_update_bits_check(host->regmap, SUN4I_SPDIF_TXCHSTA0,
+				 GENMASK(31,0), reg, &chg0);
+
+	reg = (u32)status[5] << 8;
+	reg |= (u32)status[4];
+
+	regmap_update_bits_check(host->regmap, SUN4I_SPDIF_TXCHSTA1,
+				 GENMASK(9,0), reg, &chg1);
+
+	reg = SUN4I_SPDIF_TXCFG_CHSTMODE;
+	if (status[0] & IEC958_AES0_NONAUDIO)
+		reg |= SUN4I_SPDIF_TXCFG_NONAUDIO;
+
+	regmap_update_bits(host->regmap, SUN4I_SPDIF_TXCFG,
+			   SUN4I_SPDIF_TXCFG_CHSTMODE |
+			   SUN4I_SPDIF_TXCFG_NONAUDIO, reg);
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return chg0 || chg1;
+}
+
+static struct snd_kcontrol_new sun4i_spdif_controls[] = {
+	{
+		.access = SNDRV_CTL_ELEM_ACCESS_READ,
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
+		.info = sun4i_spdif_info,
+		.get = sun4i_spdif_get_status_mask
+	},
+	{
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
+		.info = sun4i_spdif_info,
+		.get = sun4i_spdif_get_status,
+		.put = sun4i_spdif_set_status
+	}
+};
+
 static int sun4i_spdif_soc_dai_probe(struct snd_soc_dai *dai)
 {
 	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(dai);
 
 	snd_soc_dai_init_dma_data(dai, &host->dma_params_tx, NULL);
+	snd_soc_add_dai_controls(dai, sun4i_spdif_controls,
+				 ARRAY_SIZE(sun4i_spdif_controls));
+
 	return 0;
 }
 
@@ -512,6 +626,7 @@ static int sun4i_spdif_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	host->pdev = pdev;
+	spin_lock_init(&host->lock);
 
 	/* Initialize this copy of the CPU DAI driver structure */
 	memcpy(&host->cpu_dai_drv, &sun4i_spdif_dai, sizeof(sun4i_spdif_dai));