diff options
Diffstat (limited to 'sound/arm/pxa2xx-ac97.c')
| -rw-r--r-- | sound/arm/pxa2xx-ac97.c | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/sound/arm/pxa2xx-ac97.c b/sound/arm/pxa2xx-ac97.c index dda64beb202b..3acbc6023d19 100644 --- a/sound/arm/pxa2xx-ac97.c +++ b/sound/arm/pxa2xx-ac97.c @@ -37,39 +37,47 @@ static DECLARE_MUTEX(car_mutex); static DECLARE_WAIT_QUEUE_HEAD(gsr_wq); static volatile long gsr_bits; +/* + * Beware PXA27x bugs: + * + * o Slot 12 read from modem space will hang controller. + * o CDONE, SDONE interrupt fails after any slot 12 IO. + * + * We therefore have an hybrid approach for waiting on SDONE (interrupt or + * 1 jiffy timeout if interrupt never comes). + */ + static unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg) { unsigned short val = -1; volatile u32 *reg_addr; down(&car_mutex); - if (CAR & CAR_CAIP) { - printk(KERN_CRIT"%s: CAR_CAIP already set\n", __FUNCTION__); - goto out; - } /* set up primary or secondary codec space */ reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE; reg_addr += (reg >> 1); /* start read access across the ac97 link */ + GSR = GSR_CDONE | GSR_SDONE; gsr_bits = 0; val = *reg_addr; if (reg == AC97_GPIO_STATUS) goto out; - wait_event_timeout(gsr_wq, gsr_bits & GSR_SDONE, 1); - if (!gsr_bits & GSR_SDONE) { + if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 && + !((GSR | gsr_bits) & GSR_SDONE)) { printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n", - __FUNCTION__, reg, gsr_bits); + __FUNCTION__, reg, GSR | gsr_bits); val = -1; goto out; } /* valid data now */ + GSR = GSR_CDONE | GSR_SDONE; gsr_bits = 0; val = *reg_addr; /* but we've just started another cycle... */ - wait_event_timeout(gsr_wq, gsr_bits & GSR_SDONE, 1); + wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1); out: up(&car_mutex); return val; @@ -81,22 +89,19 @@ static void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigne down(&car_mutex); - if (CAR & CAR_CAIP) { - printk(KERN_CRIT "%s: CAR_CAIP already set\n", __FUNCTION__); - goto out; - } - /* set up primary or secondary codec space */ reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE; reg_addr += (reg >> 1); + + GSR = GSR_CDONE | GSR_SDONE; gsr_bits = 0; *reg_addr = val; - wait_event_timeout(gsr_wq, gsr_bits & GSR_CDONE, 1); - if (!gsr_bits & GSR_SDONE) + if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 && + !((GSR | gsr_bits) & GSR_CDONE)) printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n", - __FUNCTION__, reg, gsr_bits); + __FUNCTION__, reg, GSR | gsr_bits); -out: up(&car_mutex); + up(&car_mutex); } static void pxa2xx_ac97_reset(struct snd_ac97 *ac97) |