From: Dmitry Baryshkov dbaryshkov@gmail.com
If AC97 unit is in partially enabled state, early request_irq can trigger IRQ storm or even full hang up. Workaround this by forcibly switching ACLINK off at the start of the probe.
Signed-off-by: Dmitry Baryshkov dbaryshkov@gmail.com --- sound/arm/pxa2xx-ac97-lib.c | 25 ++++++++++++++++--------- 1 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/sound/arm/pxa2xx-ac97-lib.c b/sound/arm/pxa2xx-ac97-lib.c index ef6539e..35afd0c 100644 --- a/sound/arm/pxa2xx-ac97-lib.c +++ b/sound/arm/pxa2xx-ac97-lib.c @@ -321,10 +321,6 @@ int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev) { int ret;
- ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL); - if (ret < 0) - goto err; - if (cpu_is_pxa25x() || cpu_is_pxa27x()) { pxa_gpio_mode(GPIO31_SYNC_AC97_MD); pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD); @@ -339,7 +335,7 @@ int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev) if (IS_ERR(ac97conf_clk)) { ret = PTR_ERR(ac97conf_clk); ac97conf_clk = NULL; - goto err_irq; + goto err_conf; } }
@@ -347,19 +343,30 @@ int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev) if (IS_ERR(ac97_clk)) { ret = PTR_ERR(ac97_clk); ac97_clk = NULL; - goto err_irq; + goto err_clk; }
- return clk_enable(ac97_clk); + ret = clk_enable(ac97_clk); + if (ret) + goto err_clk2; + + ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, IRQF_DISABLED, "AC97", NULL); + if (ret < 0) + goto err_irq; + + return 0;
err_irq: GCR |= GCR_ACLINK_OFF; +err_clk2: + clk_put(ac97_clk); + ac97_clk = NULL; +err_clk: if (ac97conf_clk) { clk_put(ac97conf_clk); ac97conf_clk = NULL; } - free_irq(IRQ_AC97, NULL); -err: +err_conf: return ret; } EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);