ALSA: hda: Using polling mode for loongson controller by default

On loongson controller, RIRBSTS.RINTFL cannot be cleared,
azx_interrupt() is called all the time. We disable RIRB
interrupt, and use polling mode by default.
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Yingkun Meng <mengyingkun@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/r/d309a75424d438b958d90d797b4f1ba45468e090.1686128807.git.siyanteng@loongson.cnSigned-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/hdaudio.h

@@ -347,6 +347,7 @@ struct hdac_bus {
 	bool corbrp_self_clear:1;	/* CORBRP clears itself after reset */
 	bool polling_mode:1;
 	bool needs_damn_long_delay:1;
+	bool not_use_interrupts:1;	/* prohibiting the RIRB IRQ */
 
 	int poll_count;
 

sound/hda/hdac_controller.c

@@ -79,7 +79,10 @@ void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus)
 	/* set N=1, get RIRB response interrupt for new entry */
 	snd_hdac_chip_writew(bus, RINTCNT, 1);
 	/* enable rirb dma and response irq */
-	snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN | AZX_RBCTL_IRQ_EN);
+	if (bus->not_use_interrupts)
+		snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN);
+	else
+		snd_hdac_chip_writeb(bus, RIRBCTL, AZX_RBCTL_DMA_EN | AZX_RBCTL_IRQ_EN);
 	/* Accept unsolicited responses */
 	snd_hdac_chip_updatel(bus, GCTL, AZX_GCTL_UNSOL, AZX_GCTL_UNSOL);
 	spin_unlock_irq(&bus->reg_lock);

sound/pci/hda/hda_intel.c

@@ -1875,6 +1875,11 @@ static int azx_first_init(struct azx *chip)
 	if (chip->driver_type == AZX_DRIVER_GFHDMI)
 		bus->polling_mode = 1;
 
+	if (chip->driver_type == AZX_DRIVER_LOONGSON) {
+		bus->polling_mode = 1;
+		bus->not_use_interrupts = 1;
+	}
+
 	err = pcim_iomap_regions(pci, 1 << 0, "ICH HD audio");
 	if (err < 0)
 		return err;