linux-kernel - Re: [PATCH 4/4] iio: ti_am335x_adc: Add continuous sampling and trigger support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 16 Aug 2013 15:25:49 +0200
From:	Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To:	Zubair Lutfullah <zubair.lutfullah@...il.com>
Cc:	jic23@....ac.uk, dmitry.torokhov@...il.com,
	linux-iio@...r.kernel.org, linux-input@...r.kernel.org,
	linux-kernel@...r.kernel.org, gregkh@...uxfoundation.org,
	Russ.Dill@...com
Subject: Re: [PATCH 4/4] iio: ti_am335x_adc: Add continuous sampling and
 trigger support

* 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,
> {
…
>+	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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/