ASoC: add locking to mpc5200-psc-ac97 driver

AC97 bus register read/write hooks need to provide locking, but the
mpc5200-psc-ac97 driver does not.  This patch adds a mutex around
the register access routines.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Jon Smirl <jonsmirl@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Grant Likely 2009-07-02 11:57:25 -06:00 committed by Mark Brown
parent 07573534b0
commit 0827d6ba0b
3 changed files with 14 additions and 1 deletions

View file

@ -456,6 +456,7 @@ int mpc5200_audio_dma_create(struct of_device *op)
return -ENODEV;
spin_lock_init(&psc_dma->lock);
mutex_init(&psc_dma->mutex);
psc_dma->id = be32_to_cpu(*prop);
psc_dma->irq = irq;
psc_dma->psc_regs = regs;

View file

@ -55,6 +55,7 @@ struct psc_dma {
unsigned int irq;
struct device *dev;
spinlock_t lock;
struct mutex mutex;
u32 sicr;
uint sysclk;
int imr;

View file

@ -34,11 +34,14 @@ 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;
}
@ -54,16 +57,19 @@ 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;
}
@ -72,16 +78,21 @@ 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)