--- zzzz-none-000/linux-3.10.107/sound/pci/oxygen/oxygen_io.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/sound/pci/oxygen/oxygen_io.c	2021-02-04 17:41:59.000000000 +0000
@@ -20,9 +20,9 @@
 #include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/export.h>
+#include <linux/io.h>
 #include <sound/core.h>
 #include <sound/mpu401.h>
-#include <asm/io.h>
 #include "oxygen.h"
 
 u8 oxygen_read8(struct oxygen *chip, unsigned int reg)
@@ -147,7 +147,7 @@
 			return;
 		}
 	}
-	snd_printk(KERN_ERR "AC'97 write timeout\n");
+	dev_err(chip->card->dev, "AC'97 write timeout\n");
 }
 EXPORT_SYMBOL(oxygen_write_ac97);
 
@@ -179,7 +179,7 @@
 			reg ^= 0xffff;
 		}
 	}
-	snd_printk(KERN_ERR "AC'97 read timeout on codec %u\n", codec);
+	dev_err(chip->card->dev, "AC'97 read timeout on codec %u\n", codec);
 	return 0;
 }
 EXPORT_SYMBOL(oxygen_read_ac97);
@@ -194,23 +194,36 @@
 }
 EXPORT_SYMBOL(oxygen_write_ac97_masked);
 
-void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
+static int oxygen_wait_spi(struct oxygen *chip)
 {
 	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) {
+	/*
+	 * Higher timeout to be sure: 200 us;
+	 * actual transaction should not need more than 40 us.
+	 */
+	for (count = 50; count > 0; count--) {
 		udelay(4);
-		--count;
+		if ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) &
+						OXYGEN_SPI_BUSY) == 0)
+			return 0;
 	}
+	dev_err(chip->card->dev, "oxygen: SPI wait timeout\n");
+	return -EIO;
+}
 
+int oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
+{
+	/*
+	 * 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);
 
@@ -275,5 +288,5 @@
 		      & OXYGEN_EEPROM_BUSY))
 			return;
 	}
-	snd_printk(KERN_ERR "EEPROM write timeout\n");
+	dev_err(chip->card->dev, "EEPROM write timeout\n");
 }