| Message ID | 20200221114943.2056-3-alexandru.ardelean@analog.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] iio: imu: adis: add doc-string for 'adis' struct | expand |
On Fri, 21 Feb 2020 13:49:43 +0200 Alexandru Ardelean <alexandru.ardelean@analog.com> wrote: > The 'state_lock' mutex was renamed from 'txrx_lock' in a previous patch and > is intended to be used by ADIS drivers to protect the state of devices > during consecutive R/W ops. > The initial patch that introduced this change did not do a good [well, any] > job at explaining this. This patch adds a comment to the 'state_lock' > better explaining it's use. Nice work. Will pick up in v2. Thanks, Jonathan > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> > --- > include/linux/iio/imu/adis.h | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h > index 11c915b61ae2..a3110c097fa1 100644 > --- a/include/linux/iio/imu/adis.h > +++ b/include/linux/iio/imu/adis.h > @@ -98,6 +98,17 @@ struct adis { > const struct adis_data *data; > struct adis_burst *burst; > > + /** > + * The state_lock is meant to be used during operations that require > + * a sequence of SPI R/W in order to protect the SPI transfer > + * information (fields 'xfer', 'msg' & 'current_page') between > + * potential concurrent accesses. > + * This lock is used by all "adis_{functions}" that have to read/write > + * registers. These functions also have unlocked variants > + * (see "__adis_{functions}"), which don't hold this lock. > + * This allows users of the ADIS library to group SPI R/W into > + * the drivers, but they also must manage this lock themselves. > + */ > struct mutex state_lock; > struct spi_message msg; > struct spi_transfer *xfer;
diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h index 11c915b61ae2..a3110c097fa1 100644 --- a/include/linux/iio/imu/adis.h +++ b/include/linux/iio/imu/adis.h @@ -98,6 +98,17 @@ struct adis { const struct adis_data *data; struct adis_burst *burst; + /** + * The state_lock is meant to be used during operations that require + * a sequence of SPI R/W in order to protect the SPI transfer + * information (fields 'xfer', 'msg' & 'current_page') between + * potential concurrent accesses. + * This lock is used by all "adis_{functions}" that have to read/write + * registers. These functions also have unlocked variants + * (see "__adis_{functions}"), which don't hold this lock. + * This allows users of the ADIS library to group SPI R/W into + * the drivers, but they also must manage this lock themselves. + */ struct mutex state_lock; struct spi_message msg; struct spi_transfer *xfer;
The 'state_lock' mutex was renamed from 'txrx_lock' in a previous patch and is intended to be used by ADIS drivers to protect the state of devices during consecutive R/W ops. The initial patch that introduced this change did not do a good [well, any] job at explaining this. This patch adds a comment to the 'state_lock' better explaining it's use. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> --- include/linux/iio/imu/adis.h | 11 +++++++++++ 1 file changed, 11 insertions(+)