Re: [PATCH 4/4] iio: ti_am335x_adc: Add continuous sampling andtrigger support

From: Sebastian Andrzej Siewior
Date: Fri Aug 16 2013 - 09:25:58 EST


* Zubair Lutfullah | 2013-08-13 21:05:03 [+0100]:

>diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
>index 3ceac3e..0d7e313 100644
>--- a/drivers/iio/adc/ti_am335x_adc.c
>+++ b/drivers/iio/adc/ti_am335x_adc.c
>@@ -141,58 +350,51 @@ static int tiadc_read_raw(struct iio_dev *indio_dev,
> {
â
>+ if (iio_buffer_enabled(indio_dev))
>+ return -EBUSY;
>+ else {

You can drop else so you lose one ident level.

>+ unsigned long timeout = jiffies + usecs_to_jiffies
>+ (IDLE_TIMEOUT * adc_dev->channels);

What computing this once? ->channels is assigned at probe time.

>+ step_en = get_adc_step_mask(adc_dev);
>+ am335x_tsc_se_set(adc_dev->mfd_tscadc, step_en);
>+
>+ /* Wait for ADC sequencer to complete sampling */
>+ while (tiadc_readl(adc_dev, REG_ADCFSM) & SEQ_STATUS) {
>+ if (time_after(jiffies, timeout))
>+ return -EAGAIN;

You should check the condition after the timeout occured once again. It
is possible that the task performing the read has been pushed away by a
higher prio task (or preempted incase this sounds like a bully) and
after it got back on the cpu the timeout occured but the condition is
valid and no reason for -EAGAIN.

>+ }
and the bracket needs to left by one tab.

Sebastian
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