1 files changed, 18 insertions, 2 deletions

diff --git a/sound/soc/fsl/mpc5200_psc_ac97.c b/sound/soc/fsl/mpc5200_psc_ac97.c
index 794a247..c4ae3e0 100644
--- a/sound/soc/fsl/mpc5200_psc_ac97.c
+++ b/sound/soc/fsl/mpc5200_psc_ac97.c
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/delay.h>
 
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
@@ -34,13 +35,20 @@ static unsigned short psc_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
 	int status;
 	unsigned int val;
 
+	mutex_lock(&psc_dma->mutex);
+
 	/* Wait for command send status zero = ready */
 	status = spin_event_timeout(!(in_be16(&psc_dma->psc_regs->sr_csr.status) &
 				MPC52xx_PSC_SR_CMDSEND), 100, 0);
 	if (status == 0) {
 		pr_err("timeout on ac97 bus (rdy)\n");
+		mutex_unlock(&psc_dma->mutex);
 		return -ENODEV;
 	}
+
+	/* Force clear the data valid bit */
+	in_be32(&psc_dma->psc_regs->ac97_data);
+
 	/* Send the read */
 	out_be32(&psc_dma->psc_regs->ac97_cmd, (1<<31) | ((reg & 0x7f) << 24));
 
@@ -50,16 +58,19 @@ static unsigned short psc_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
 	if (status == 0) {
 		pr_err("timeout on ac97 read (val) %x\n",
 				in_be16(&psc_dma->psc_regs->sr_csr.status));
+		mutex_unlock(&psc_dma->mutex);
 		return -ENODEV;
 	}
 	/* Get the data */
 	val = in_be32(&psc_dma->psc_regs->ac97_data);
 	if (((val >> 24) & 0x7f) != reg) {
 		pr_err("reg echo error on ac97 read\n");
+		mutex_unlock(&psc_dma->mutex);
 		return -ENODEV;
 	}
 	val = (val >> 8) & 0xffff;
 
+	mutex_unlock(&psc_dma->mutex);
 	return (unsigned short) val;
 }
 
@@ -68,16 +79,21 @@ static void psc_ac97_write(struct snd_ac97 *ac97,
 {
 	int status;
 
+	mutex_lock(&psc_dma->mutex);
+
 	/* Wait for command status zero = ready */
 	status = spin_event_timeout(!(in_be16(&psc_dma->psc_regs->sr_csr.status) &
 				MPC52xx_PSC_SR_CMDSEND), 100, 0);
 	if (status == 0) {
 		pr_err("timeout on ac97 bus (write)\n");
-		return;
+		goto out;
 	}
 	/* Write data */
 	out_be32(&psc_dma->psc_regs->ac97_cmd,
 			((reg & 0x7f) << 24) | (val << 8));
+
+ out:
+	mutex_unlock(&psc_dma->mutex);
 }
 
 static void psc_ac97_warm_reset(struct snd_ac97 *ac97)
@@ -97,7 +113,7 @@ static void psc_ac97_cold_reset(struct snd_ac97 *ac97)
 	out_8(&regs->op1, MPC52xx_PSC_OP_RES);
 	udelay(10);
 	out_8(&regs->op0, MPC52xx_PSC_OP_RES);
-	udelay(50);
+	msleep(1);
 	psc_ac97_warm_reset(ac97);
 }