From 9dde479e9f9e5b2eafa3db8b7ce919b74533beb8 Mon Sep 17 00:00:00 2001 From: simran singhal Date: Wed, 22 Mar 2017 21:50:43 +0530 Subject: [PATCH] staging: iio: adis16060: Remove iio_dev mlock and refactor code The IIO subsystem is redefining iio_dev->mlock to be used by the IIO core only for protecting device operating mode changes. ie. Changes between INDIO_DIRECT_MODE, INDIO_BUFFER_* modes. In this driver, mlock was being used to protect hardware state changes. In the driver, buf_lock protects both the adis16060_spi_write() and adis16060_spi_read() functions and both are always called in pair. First write, then read. Refactor the code to have one single function adis16060_spi_write_than_read() protected by the buf_lock. This removes the need for additional locking via mlock, so this locking is removed. Signed-off-by: simran singhal Signed-off-by: Jonathan Cameron --- drivers/staging/iio/gyro/adis16060_core.c | 35 +++++++++---------------------- 1 file changed, 10 insertions(+), 25 deletions(-) diff --git a/drivers/staging/iio/gyro/adis16060_core.c b/drivers/staging/iio/gyro/adis16060_core.c index c9d46e796f79..811596234823 100644 --- a/drivers/staging/iio/gyro/adis16060_core.c +++ b/drivers/staging/iio/gyro/adis16060_core.c @@ -40,25 +40,20 @@ struct adis16060_state { static struct iio_dev *adis16060_iio_dev; -static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val) +static int adis16060_spi_write_than_read(struct iio_dev *indio_dev, + u8 conf, u16 *val) { int ret; struct adis16060_state *st = iio_priv(indio_dev); mutex_lock(&st->buf_lock); - st->buf[2] = val; /* The last 8 bits clocked in are latched */ + st->buf[2] = conf; /* The last 8 bits clocked in are latched */ ret = spi_write(st->us_w, st->buf, 3); - mutex_unlock(&st->buf_lock); - - return ret; -} - -static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val) -{ - int ret; - struct adis16060_state *st = iio_priv(indio_dev); - mutex_lock(&st->buf_lock); + if (ret < 0) { + mutex_unlock(&st->buf_lock); + return ret; + } ret = spi_read(st->us_r, st->buf, 3); @@ -86,17 +81,11 @@ static int adis16060_read_raw(struct iio_dev *indio_dev, switch (mask) { case IIO_CHAN_INFO_RAW: - /* Take the iio_dev status lock */ - mutex_lock(&indio_dev->mlock); - ret = adis16060_spi_write(indio_dev, chan->address); + ret = adis16060_spi_write_than_read(indio_dev, + chan->address, &tval); if (ret < 0) - goto out_unlock; + return ret; - ret = adis16060_spi_read(indio_dev, &tval); - if (ret < 0) - goto out_unlock; - - mutex_unlock(&indio_dev->mlock); *val = tval; return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: @@ -110,10 +99,6 @@ static int adis16060_read_raw(struct iio_dev *indio_dev, } return -EINVAL; - -out_unlock: - mutex_unlock(&indio_dev->mlock); - return ret; } static const struct iio_info adis16060_info = { -- 2.11.0