ALSA: hda - Loop interrupt handling until really cleared

Currently the interrupt handler of HD-audio driver assumes that no irq
update is needed while processing the irq.  But in reality, it has
been confirmed that the HW irq is issued even during the irq
handling.  Since we clear the irq status at the beginning, process the
interrupt, then exits from the handler, the lately issued interrupt is
left untouched without being properly processed.

This patch changes the interrupt handler code to loop over the
check-and-process.  The handler tries repeatedly as long as the IRQ
status are turned on, and either stream or CORB/RIRB is handled.

For checking the stream handling, snd_hdac_bus_handle_stream_irq()
returns a value indicating the stream indices bits.  Other than that,
the change is only in the irq handler itself.

Reported-by: Libin Yang <libin.yang@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
index e2b712c90d3f22d4bcbb75ded3a296304d23d7c6..c21c38ce74501dbdac327e9cac8b0b6d051a42b0 100644 (file)
--- a/include/sound/hdaudio.h
+++ b/include/sound/hdaudio.h
@@ -343,7 +343,7 @@ void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus);
 void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus);
 
 void snd_hdac_bus_update_rirb(struct hdac_bus *bus);
-void snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
+int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
                                    void (*ack)(struct hdac_bus *,
                                                struct hdac_stream *));
 

diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c
index b5a17cb510a0b4ee71115973a7d73309e9061b03..8c486235c905253ea0609183d813362a294e42f9 100644 (file)
--- a/sound/hda/hdac_controller.c
+++ b/sound/hda/hdac_controller.c
@@ -426,18 +426,22 @@ EXPORT_SYMBOL_GPL(snd_hdac_bus_stop_chip);
  * @bus: HD-audio core bus
  * @status: INTSTS register value
  * @ask: callback to be called for woken streams
+ *
+ * Returns the bits of handled streams, or zero if no stream is handled.
  */
-void snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
+int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
                                    void (*ack)(struct hdac_bus *,
                                                struct hdac_stream *))
 {
        struct hdac_stream *azx_dev;
        u8 sd_status;
+       int handled = 0;
 
        list_for_each_entry(azx_dev, &bus->stream_list, list) {
                if (status & azx_dev->sd_int_sta_mask) {
                        sd_status = snd_hdac_stream_readb(azx_dev, SD_STS);
                        snd_hdac_stream_writeb(azx_dev, SD_STS, SD_INT_MASK);
+                       handled |= 1 << azx_dev->index;
                        if (!azx_dev->substream || !azx_dev->running ||
                            !(sd_status & SD_INT_COMPLETE))
                                continue;
@@ -445,6 +449,7 @@ void snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
                                ack(bus, azx_dev);
                }
        }
+       return handled;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_bus_handle_stream_irq);
 

diff --git a/sound/pci/hda/hda_controller.c b/sound/pci/hda/hda_controller.c
index 37cf9cee983555ad1a47e4bb43ff2e9db6de39e9..27de8015717d95fdf45ac512a77c60eb32202d67 100644 (file)
--- a/sound/pci/hda/hda_controller.c
+++ b/sound/pci/hda/hda_controller.c
@@ -930,6 +930,8 @@ irqreturn_t azx_interrupt(int irq, void *dev_id)
        struct azx *chip = dev_id;
        struct hdac_bus *bus = azx_bus(chip);
        u32 status;
+       bool active, handled = false;
+       int repeat = 0; /* count for avoiding endless loop */
 
 #ifdef CONFIG_PM
        if (azx_has_pm_runtime(chip))
@@ -939,33 +941,36 @@ irqreturn_t azx_interrupt(int irq, void *dev_id)
 
        spin_lock(&bus->reg_lock);
 
-       if (chip->disabled) {
-               spin_unlock(&bus->reg_lock);
-               return IRQ_NONE;
-       }
-
-       status = azx_readl(chip, INTSTS);
-       if (status == 0 || status == 0xffffffff) {
-               spin_unlock(&bus->reg_lock);
-               return IRQ_NONE;
-       }
+       if (chip->disabled)
+               goto unlock;
 
-       snd_hdac_bus_handle_stream_irq(bus, status, stream_update);
+       do {
+               status = azx_readl(chip, INTSTS);
+               if (status == 0 || status == 0xffffffff)
+                       break;
 
-       /* clear rirb int */
-       status = azx_readb(chip, RIRBSTS);
-       if (status & RIRB_INT_MASK) {
-               if (status & RIRB_INT_RESPONSE) {
-                       if (chip->driver_caps & AZX_DCAPS_CTX_WORKAROUND)
-                               udelay(80);
-                       snd_hdac_bus_update_rirb(bus);
+               handled = true;
+               active = false;
+               if (snd_hdac_bus_handle_stream_irq(bus, status, stream_update))
+                       active = true;
+
+               /* clear rirb int */
+               status = azx_readb(chip, RIRBSTS);
+               if (status & RIRB_INT_MASK) {
+                       active = true;
+                       if (status & RIRB_INT_RESPONSE) {
+                               if (chip->driver_caps & AZX_DCAPS_CTX_WORKAROUND)
+                                       udelay(80);
+                               snd_hdac_bus_update_rirb(bus);
+                       }
+                       azx_writeb(chip, RIRBSTS, RIRB_INT_MASK);
                }
-               azx_writeb(chip, RIRBSTS, RIRB_INT_MASK);
-       }
+       } while (active && ++repeat < 10);
 
+ unlock:
        spin_unlock(&bus->reg_lock);
 
-       return IRQ_HANDLED;
+       return IRQ_RETVAL(handled);
 }
 EXPORT_SYMBOL_GPL(azx_interrupt);