public inbox for linux-iio@vger.kernel.org
 help / color / mirror / Atom feed
From: Felix Gu <ustc.gu@gmail.com>
To: "Jonathan Cameron" <jic23@kernel.org>,
	"David Lechner" <dlechner@baylibre.com>,
	"Nuno Sá" <nuno.sa@analog.com>,
	"Andy Shevchenko" <andy@kernel.org>,
	"Shrikant Raskar" <raskar.shree97@gmail.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	 linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
	 Felix Gu <ustc.gu@gmail.com>
Subject: [PATCH] iio: proximity: rfd77402: Fix completion race condition in IRQ mode
Date: Wed, 04 Mar 2026 22:14:32 +0800	[thread overview]
Message-ID: <20260304-77402-v1-1-47ad6eedd643@gmail.com> (raw)

In IRQ mode, the completion was being reinitialized after the
measurement command had already been sent to the hardware. This
created a race condition where the IRQ handler could call complete()
before reinit_completion() was executed. Consequently,
wait_for_completion_timeout() would fail to see the signal and wait
until it timed out.

Move reinit_completion() to occur before the measurement command is
triggered to ensure the synchronization primitive is ready to
capture the interrupt.

Fixes: dc81be96a73a ("iio: proximity: rfd77402: Add interrupt handling support")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
 drivers/iio/proximity/rfd77402.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/proximity/rfd77402.c b/drivers/iio/proximity/rfd77402.c
index 6afdbfca3e5a..81b8daf17a54 100644
--- a/drivers/iio/proximity/rfd77402.c
+++ b/drivers/iio/proximity/rfd77402.c
@@ -173,10 +173,8 @@ static int rfd77402_wait_for_result(struct rfd77402_data *data)
 	struct i2c_client *client = data->client;
 	int val, ret;
 
-	if (data->irq_en) {
-		reinit_completion(&data->completion);
+	if (data->irq_en)
 		return rfd77402_wait_for_irq(data);
-	}
 
 	/*
 	 * As per RFD77402 datasheet section '3.1.1 Single Measure', the
@@ -204,6 +202,9 @@ static int rfd77402_measure(struct rfd77402_data *data)
 	if (ret < 0)
 		return ret;
 
+	if (data->irq_en)
+		reinit_completion(&data->completion);
+
 	ret = i2c_smbus_write_byte_data(client, RFD77402_CMD_R,
 					RFD77402_CMD_SINGLE |
 					RFD77402_CMD_VALID);

---
base-commit: c025f6cf4209e1542ec2afebe49f42bbaf1a5c7b
change-id: 20260304-77402-ec479de1b9f6

Best regards,
-- 
Felix Gu <ustc.gu@gmail.com>


             reply	other threads:[~2026-03-04 14:14 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-04 14:14 Felix Gu [this message]
2026-03-07 17:07 ` [PATCH] iio: proximity: rfd77402: Fix completion race condition in IRQ mode Jonathan Cameron
2026-03-09 17:02 ` Shrikant
2026-03-14 11:17   ` Jonathan Cameron

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260304-77402-v1-1-47ad6eedd643@gmail.com \
    --to=ustc.gu@gmail.com \
    --cc=Jonathan.Cameron@huawei.com \
    --cc=andy@kernel.org \
    --cc=dlechner@baylibre.com \
    --cc=jic23@kernel.org \
    --cc=linux-iio@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nuno.sa@analog.com \
    --cc=raskar.shree97@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox