ALSA: oxygen: add the separate SPI waiting function

The oxygen_wait_spi() function now performs waiting when the
SPI bus completes a transaction. Introduce the timeout error
checking and increase timeout to 200 from 40.

Signed-off-by: Roman Volkov <v1ron@mail.ru>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 18 insertions, 0 deletions

diff --git a/sound/pci/oxygen/oxygen_io.c b/sound/pci/oxygen/oxygen_io.c
index 521eae458348..4b88c7a332e4 100644
--- a/sound/pci/oxygen/oxygen_io.c
+++ b/sound/pci/oxygen/oxygen_io.c
@@ -194,6 +194,24 @@ void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
 }
 EXPORT_SYMBOL(oxygen_write_ac97_masked);
 
+static int oxygen_wait_spi(struct oxygen *chip)
+{
+        unsigned int count;
+
+        /*
+         * Higher timeout to be sure: 200 us;
+         * actual transaction should not need more than 40 us.
+         */
+        for (count = 50; count > 0; count--) {
+                udelay(4);
+                if ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) &
+                                                OXYGEN_SPI_BUSY) == 0)
+                        return 0;
+        }
+        snd_printk(KERN_ERR "oxygen: SPI wait timeout\n");
+        return -EIO;
+}
+
 void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
 {
         unsigned int count;