diff options
| -rw-r--r-- | drivers/mfd/wm831x-core.c | 65 |
1 files changed, 48 insertions, 17 deletions
diff --git a/drivers/mfd/wm831x-core.c b/drivers/mfd/wm831x-core.c index f2ab025ad97a..da00ca9e0c71 100644 --- a/drivers/mfd/wm831x-core.c +++ b/drivers/mfd/wm831x-core.c @@ -322,7 +322,11 @@ EXPORT_SYMBOL_GPL(wm831x_set_bits); */ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input) { - int ret, src; + int ret, src, irq_masked, timeout; + + /* Are we using the interrupt? */ + irq_masked = wm831x_reg_read(wm831x, WM831X_INTERRUPT_STATUS_1_MASK); + irq_masked &= WM831X_AUXADC_DATA_EINT; mutex_lock(&wm831x->auxadc_lock); @@ -342,6 +346,9 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input) goto out; } + /* Clear any notification from a very late arriving interrupt */ + try_wait_for_completion(&wm831x->auxadc_done); + ret = wm831x_set_bits(wm831x, WM831X_AUXADC_CONTROL, WM831X_AUX_CVT_ENA, WM831X_AUX_CVT_ENA); if (ret < 0) { @@ -349,22 +356,46 @@ int wm831x_auxadc_read(struct wm831x *wm831x, enum wm831x_auxadc input) goto disable; } - /* If an interrupt arrived late clean up after it */ - try_wait_for_completion(&wm831x->auxadc_done); - - /* Ignore the result to allow us to soldier on without IRQ hookup */ - wait_for_completion_timeout(&wm831x->auxadc_done, msecs_to_jiffies(5)); - - ret = wm831x_reg_read(wm831x, WM831X_AUXADC_CONTROL); - if (ret < 0) { - dev_err(wm831x->dev, "AUXADC status read failed: %d\n", ret); - goto disable; - } - - if (ret & WM831X_AUX_CVT_ENA) { - dev_err(wm831x->dev, "Timed out reading AUXADC\n"); - ret = -EBUSY; - goto disable; + if (irq_masked) { + /* If we're not using interrupts then poll the + * interrupt status register */ + timeout = 5; + while (timeout) { + msleep(1); + + ret = wm831x_reg_read(wm831x, + WM831X_INTERRUPT_STATUS_1); + if (ret < 0) { + dev_err(wm831x->dev, + "ISR 1 read failed: %d\n", ret); + goto disable; + } + + /* Did it complete? */ + if (ret & WM831X_AUXADC_DATA_EINT) { + wm831x_reg_write(wm831x, + WM831X_INTERRUPT_STATUS_1, + WM831X_AUXADC_DATA_EINT); + break; + } else { + dev_err(wm831x->dev, + "AUXADC conversion timeout\n"); + ret = -EBUSY; + goto disable; + } + } + } else { + /* If we are using interrupts then wait for the + * interrupt to complete. Use an extremely long + * timeout to handle situations with heavy load where + * the notification of the interrupt may be delayed by + * threaded IRQ handling. */ + if (!wait_for_completion_timeout(&wm831x->auxadc_done, + msecs_to_jiffies(500))) { + dev_err(wm831x->dev, "Timed out waiting for AUXADC\n"); + ret = -EBUSY; + goto disable; + } } ret = wm831x_reg_read(wm831x, WM831X_AUXADC_DATA); |