On 20/03/17 07:39, Gargi Sharma wrote:
> 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. Replace it with buf_lock in the devices global data.
>
> As buf_lock already protects operations in ade7754_write_frequency,
> there isn't a need to acquire the lock inside ade7754_spi_write_reg_8
> when writing to the register.
>
> Signed-off-by: Gargi Sharma <gs051095@xxxxxxxxx>
Question inline.
> ---
> drivers/staging/iio/meter/ade7754.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/iio/meter/ade7754.c b/drivers/staging/iio/meter/ade7754.c
> index 024463a..eb03469 100644
> --- a/drivers/staging/iio/meter/ade7754.c
> +++ b/drivers/staging/iio/meter/ade7754.c
> @@ -29,6 +29,15 @@ static int ade7754_spi_write_reg_8(struct device *dev, u8 reg_address, u8 val)
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> struct ade7754_state *st = iio_priv(indio_dev);
>
> + if (reg_address == ADE7754_WAVMODE) {
> + st->tx[0] = ADE7754_WRITE_REG(reg_address);
> + st->tx[1] = val;
> +
> + ret = spi_write(st->us, st->tx, 2);
> +
> + return ret;
> + }
This block doesn't fit with the description. What's going on here?
> +
> mutex_lock(&st->buf_lock);
> st->tx[0] = ADE7754_WRITE_REG(reg_address);
> st->tx[1] = val;
> @@ -430,7 +439,7 @@ static ssize_t ade7754_write_frequency(struct device *dev,
> if (!val)
> return -EINVAL;
>
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&st->buf_lock);
>
> t = 26000 / val;
> if (t > 0)
> @@ -451,7 +460,7 @@ static ssize_t ade7754_write_frequency(struct device *dev,
> ret = ade7754_spi_write_reg_8(dev, ADE7754_WAVMODE, reg);
>
> out:
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&st->buf_lock);
>
> return ret ? ret : len;
> }
>
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
