mfd/tc3589x: fix random interrupt misses

On the TC35892, a random delayed interrupt clear (GPIO IC) write locks up the
child interrupts. In such a case, the original interrupt is active and not yet
acknowledged. Re-check the IRQST bit for any pending interrupts and handle
those.

Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Sundar Iyer <sundar.iyer@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
This commit is contained in:
Sundar Iyer 2010-12-13 09:33:16 +05:30 committed by Linus Walleij
parent 611b7590af
commit bd77efd0ce

View File

@ -142,6 +142,7 @@ static irqreturn_t tc3589x_irq(int irq, void *data)
struct tc3589x *tc3589x = data;
int status;
again:
status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
if (status < 0)
return IRQ_NONE;
@ -156,9 +157,12 @@ static irqreturn_t tc3589x_irq(int irq, void *data)
/*
* A dummy read or write (to any register) appears to be necessary to
* have the last interrupt clear (for example, GPIO IC write) take
* effect.
* effect. In such a case, recheck for any interrupt which is still
* pending.
*/
tc3589x_reg_read(tc3589x, TC3589x_IRQST);
status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
if (status)
goto again;
return IRQ_HANDLED;
}