From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f195.google.com ([209.85.192.195]:36305 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754569AbcHYGpk (ORCPT ); Thu, 25 Aug 2016 02:45:40 -0400 Received: by mail-pf0-f195.google.com with SMTP id y134so2658488pfg.3 for ; Wed, 24 Aug 2016 23:45:01 -0700 (PDT) From: Matt Ranostay To: linux-iio@vger.kernel.org Cc: jic23@kernel.org, Matt Ranostay Subject: [PATCH v2 4/4] iio: chemical: vz89x: remove mutex and replace with iio_device_*_direct_mode Date: Wed, 24 Aug 2016 23:44:50 -0700 Message-Id: <1472107490-11924-5-git-send-email-mranostay@gmail.com> In-Reply-To: <1472107490-11924-1-git-send-email-mranostay@gmail.com> References: <1472107490-11924-1-git-send-email-mranostay@gmail.com> Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org There is no reason to have a seperate mutex when indio_dev->mlock can be used with the iio_device_*_direct_mode helpers. Also avoid a race condition that is possible with multiple IIO_RESISTANCE reads. Signed-off-by: Matt Ranostay --- drivers/iio/chemical/vz89x.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/drivers/iio/chemical/vz89x.c b/drivers/iio/chemical/vz89x.c index cd3870ead3fd..5e5d4a9abe63 100644 --- a/drivers/iio/chemical/vz89x.c +++ b/drivers/iio/chemical/vz89x.c @@ -16,7 +16,6 @@ */ #include -#include #include #include #include @@ -52,7 +51,6 @@ struct vz89x_chip_data; struct vz89x_data { struct i2c_client *client; const struct vz89x_chip_data *chip; - struct mutex lock; int (*xfer)(struct vz89x_data *data, u8 cmd); bool is_valid; @@ -277,26 +275,32 @@ static int vz89x_read_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_RAW: - mutex_lock(&data->lock); - ret = vz89x_get_measurement(data); - mutex_unlock(&data->lock); - + ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; + ret = vz89x_get_measurement(data); + if (ret) + goto error_out; + switch (chan->type) { case IIO_CONCENTRATION: *val = data->buffer[chan->address]; - return IIO_VAL_INT; + ret = IIO_VAL_INT; + break; case IIO_RESISTANCE: ret = vz89x_get_resistance_reading(data, chan, val); if (!ret) - return IIO_VAL_INT; + ret = IIO_VAL_INT; break; default: - return -EINVAL; + ret = -EINVAL; } - break; + +error_out: + iio_device_release_direct_mode(indio_dev); + + return ret; case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_RESISTANCE: @@ -390,7 +394,6 @@ static int vz89x_probe(struct i2c_client *client, data->client = client; data->chip = &vz89x_chips[chip_id]; data->last_update = jiffies - HZ; - mutex_init(&data->lock); indio_dev->dev.parent = &client->dev; indio_dev->info = &vz89x_info, -- 2.7.4