[alsa-devel] [PATCH v3 02/16] ALSA: Oxygen: Modify the SPI writing function

[Roman Volkov]

The SPI writing function modified to use the new
waiting function. Return value changed from void
to int, so it can return error codes. Older drivers
just ignore that return value, the Xonar DG/DGX
driver handles this value. We need to wait AFTER
initiating the SPI transaction, otherwise read
operation will not work.

Signed-off-by: Roman Volkov <v1ron at mail.ru>
---
 sound/pci/oxygen/oxygen.h    |    2 +-
 sound/pci/oxygen/oxygen_io.c |   15 ++++-----------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/sound/pci/oxygen/oxygen.h b/sound/pci/oxygen/oxygen.h
index 09a24b2..c10ab07 100644
--- a/sound/pci/oxygen/oxygen.h
+++ b/sound/pci/oxygen/oxygen.h
@@ -198,7 +198,7 @@ void oxygen_write_ac97(struct oxygen *chip, unsigned int codec,
 void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
 			      unsigned int index, u16 data, u16 mask);
 
-void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data);
+int oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data);
 void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data);
 
 void oxygen_reset_uart(struct oxygen *chip);
diff --git a/sound/pci/oxygen/oxygen_io.c b/sound/pci/oxygen/oxygen_io.c
index a917f37..fb9c826 100644
--- a/sound/pci/oxygen/oxygen_io.c
+++ b/sound/pci/oxygen/oxygen_io.c
@@ -209,23 +209,16 @@ static int oxygen_wait_spi(struct oxygen *chip)
 	return -EIO;
 }
 
-void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
+int oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
 {
-	unsigned int count;
-
-	/* should not need more than 30.72 us (24 * 1.28 us) */
-	count = 10;
-	while ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) & OXYGEN_SPI_BUSY)
-	       && count > 0) {
-		udelay(4);
-		--count;
-	}
-
+	/* We need to wait AFTER initiating the SPI transaction,
+	   otherwise read operations will not work */
 	oxygen_write8(chip, OXYGEN_SPI_DATA1, data);
 	oxygen_write8(chip, OXYGEN_SPI_DATA2, data >> 8);
 	if (control & OXYGEN_SPI_DATA_LENGTH_3)
 		oxygen_write8(chip, OXYGEN_SPI_DATA3, data >> 16);
 	oxygen_write8(chip, OXYGEN_SPI_CONTROL, control);
+	return oxygen_wait_spi(chip);
 }
 EXPORT_SYMBOL(oxygen_write_spi);
 
-- 
1.7.10.4