[ALSA] oxygen: use AC97 interrupt

After an AC97 register read or write, use the AC97 interrupt instead of
polling to wait for the access to be completed.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/sound/pci/oxygen/oxygen.h b/sound/pci/oxygen/oxygen.h
index 8fc9e7ca11823cff16e3e1c06dd88c494f58ff66..55ce2448805d2df48bc42d60ab06ccaf133ec1b8 100644 (file)
--- a/sound/pci/oxygen/oxygen.h
+++ b/sound/pci/oxygen/oxygen.h
@@ -3,6 +3,7 @@
 
 #include <linux/mutex.h>
 #include <linux/spinlock.h>
+#include <linux/wait.h>
 #include <linux/workqueue.h>
 #include "oxygen_regs.h"
 
@@ -65,6 +66,7 @@ struct oxygen {
        struct snd_pcm_substream *streams[PCM_COUNT];
        struct snd_kcontrol *controls[CONTROL_COUNT];
        struct work_struct spdif_input_bits_work;
+       wait_queue_head_t ac97_waitqueue;
 };
 
 struct oxygen_model {

diff --git a/sound/pci/oxygen/oxygen_io.c b/sound/pci/oxygen/oxygen_io.c
index d0cdce041dd800b589eb1e9a649191c1793a0044..74e23ef9c9467aaf3a54bacb2beb7315a4d36ea8 100644 (file)
--- a/sound/pci/oxygen/oxygen_io.c
+++ b/sound/pci/oxygen/oxygen_io.c
@@ -85,14 +85,22 @@ EXPORT_SYMBOL(oxygen_write32_masked);
 
 static int oxygen_ac97_wait(struct oxygen *chip, unsigned int mask)
 {
-       unsigned long timeout = jiffies + msecs_to_jiffies(1);
-       do {
-               udelay(5);
-               cond_resched();
-               if (oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS) & mask)
-                       return 0;
-       } while (time_after_eq(timeout, jiffies));
-       return -EIO;
+       u8 status = 0;
+
+       /*
+        * Reading the status register also clears the bits, so we have to save
+        * the read bits in status.
+        */
+       wait_event_timeout(chip->ac97_waitqueue,
+                          ({ status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
+                             status & mask; }),
+                          msecs_to_jiffies(1) + 1);
+       /*
+        * Check even after a timeout because this function should not require
+        * the AC'97 interrupt to be enabled.
+        */
+       status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
+       return status & mask ? 0 : -EIO;
 }
 
 /*

diff --git a/sound/pci/oxygen/oxygen_lib.c b/sound/pci/oxygen/oxygen_lib.c
index d98867c1f2d4ab76d2f2bbe18fea4ac6e192d793..de6bf41c3e961ff69c391b46d5bdec09a3bdf6ad 100644 (file)
--- a/sound/pci/oxygen/oxygen_lib.c
+++ b/sound/pci/oxygen/oxygen_lib.c
@@ -53,7 +53,8 @@ static irqreturn_t oxygen_interrupt(int dummy, void *dev_id)
                          OXYGEN_CHANNEL_MULTICH |
                          OXYGEN_CHANNEL_AC97 |
                          OXYGEN_INT_SPDIF_IN_DETECT |
-                         OXYGEN_INT_GPIO);
+                         OXYGEN_INT_GPIO |
+                         OXYGEN_INT_AC97);
        if (clear) {
                if (clear & OXYGEN_INT_SPDIF_IN_DETECT)
                        chip->interrupt_mask &= ~OXYGEN_INT_SPDIF_IN_DETECT;
@@ -89,6 +90,9 @@ static irqreturn_t oxygen_interrupt(int dummy, void *dev_id)
        if ((status & OXYGEN_INT_MIDI) && chip->midi)
                snd_mpu401_uart_interrupt(0, chip->midi->private_data);
 
+       if (status & OXYGEN_INT_AC97)
+               wake_up(&chip->ac97_waitqueue);
+
        return IRQ_HANDLED;
 }
 
@@ -306,7 +310,9 @@ static void __devinit oxygen_init(struct oxygen *chip)
                      (2 << OXYGEN_A_MONITOR_ROUTE_2_SHIFT) |
                      (3 << OXYGEN_A_MONITOR_ROUTE_3_SHIFT));
 
-       oxygen_write8(chip, OXYGEN_AC97_INTERRUPT_MASK, 0);
+       oxygen_write8(chip, OXYGEN_AC97_INTERRUPT_MASK,
+                     OXYGEN_AC97_INT_READ_DONE |
+                     OXYGEN_AC97_INT_WRITE_DONE);
        oxygen_write32(chip, OXYGEN_AC97_OUT_CONFIG, 0);
        oxygen_write32(chip, OXYGEN_AC97_IN_CONFIG, 0);
        if (!(chip->has_ac97_0 | chip->has_ac97_1))
@@ -408,6 +414,7 @@ int __devinit oxygen_pci_probe(struct pci_dev *pci, int index, char *id,
        mutex_init(&chip->mutex);
        INIT_WORK(&chip->spdif_input_bits_work,
                  oxygen_spdif_input_bits_changed);
+       init_waitqueue_head(&chip->ac97_waitqueue);
 
        err = pci_enable_device(pci);
        if (err < 0)
@@ -471,7 +478,7 @@ int __devinit oxygen_pci_probe(struct pci_dev *pci, int index, char *id,
        oxygen_proc_init(chip);
 
        spin_lock_irq(&chip->reg_lock);
-       chip->interrupt_mask |= OXYGEN_INT_SPDIF_IN_DETECT;
+       chip->interrupt_mask |= OXYGEN_INT_SPDIF_IN_DETECT | OXYGEN_INT_AC97;
        oxygen_write16(chip, OXYGEN_INTERRUPT_MASK, chip->interrupt_mask);
        spin_unlock_irq(&chip->reg_lock);