On 11/13/13 20:39, Lars-Peter Clausen wrote: > On 11/13/2013 09:27 PM, Jonathan Cameron wrote: >> From: Frank Zago <frank@xxxxxxxx> >> >> This will leave a lock held after reading from the device, preventing >> any further reads. >> >> Signed-off-by: Frank Zago <frank@xxxxxxxx> >> Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx> >> --- >> I have reworked this from a patch sent to me by Frank and put it >> into the correct format. >> >> Frank, do you mind me adding your sign off on this. It's shorter >> than your patch, but the effect is the same. This approach of unlocking >> before checking a return value is a common kernel idiom. >> >> Jonathan >> >> drivers/iio/accel/kxsd9.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c >> index d72118d1189c..12df91986dd2 100644 >> --- a/drivers/iio/accel/kxsd9.c >> +++ b/drivers/iio/accel/kxsd9.c >> @@ -112,6 +112,7 @@ static int kxsd9_read(struct iio_dev *indio_dev, u8 address) >> mutex_lock(&st->buf_lock); >> st->tx[0] = KXSD9_READ(address); >> ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers)); >> + mutex_unlock(&st->buf_lock); >> if (ret) >> return ret; >> return (((u16)(st->rx[0])) << 8) | (st->rx[1] & 0xF0); > > I think you'll need to hold the lock until you've actually read the data from the buffer. Good point, I wasn't thinking through what it was actually for. Frank was in fact much more correct. I'll post his version in a sec. > > - Lars > > -- > 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 -- 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
