| Message ID | 20220128183948.3924558-2-benjamin.walker@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | dmaengine: memset clarifications and fixes | expand |
On 28-01-22, 11:39, Ben Walker wrote: > Document this function to make clear the expected behavior of the > 'value' parameter. It was intended to match the behavior of POSIX memset > as laid out here: > > https://lore.kernel.org/dmaengine/YejrA5ZWZ3lTRO%2F1@matsya/ Can we add this to Documentation too? Documentation/driver-api/dmaengine/ > > Signed-off-by: Ben Walker <benjamin.walker@intel.com> > --- > include/linux/dmaengine.h | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h > index 842d4f7ca752d..3d3e663e17ac7 100644 > --- a/include/linux/dmaengine.h > +++ b/include/linux/dmaengine.h > @@ -1031,6 +1031,14 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma( > return chan->device->device_prep_interleaved_dma(chan, xt, flags); > } > > +/** > + * dmaengine_prep_dma_memset() - Prepare a DMA memset descriptor. > + * @chan: The channel to be used for this descriptor > + * @dest: Address of buffer to be set > + * @value: Treated as a single byte value that fills the destination buffer > + * @len: The total size of dest > + * @flags: DMA engine flags > + */ > static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset( > struct dma_chan *chan, dma_addr_t dest, int value, size_t len, > unsigned long flags) > -- > 2.33.1
On 2/15/2022 4:44 AM, Vinod Koul wrote: > On 28-01-22, 11:39, Ben Walker wrote: >> Document this function to make clear the expected behavior of the >> 'value' parameter. It was intended to match the behavior of POSIX memset >> as laid out here: >> >> https://lore.kernel.org/dmaengine/YejrA5ZWZ3lTRO%2F1@matsya/ > > Can we add this to Documentation too? Documentation/driver-api/dmaengine/ Ack. Updated in my v2. > >> >> Signed-off-by: Ben Walker <benjamin.walker@intel.com> >> --- >> include/linux/dmaengine.h | 8 ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h >> index 842d4f7ca752d..3d3e663e17ac7 100644 >> --- a/include/linux/dmaengine.h >> +++ b/include/linux/dmaengine.h >> @@ -1031,6 +1031,14 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma( >> return chan->device->device_prep_interleaved_dma(chan, xt, flags); >> } >> >> +/** >> + * dmaengine_prep_dma_memset() - Prepare a DMA memset descriptor. >> + * @chan: The channel to be used for this descriptor >> + * @dest: Address of buffer to be set >> + * @value: Treated as a single byte value that fills the destination buffer >> + * @len: The total size of dest >> + * @flags: DMA engine flags >> + */ >> static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset( >> struct dma_chan *chan, dma_addr_t dest, int value, size_t len, >> unsigned long flags) >> -- >> 2.33.1 >
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 842d4f7ca752d..3d3e663e17ac7 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -1031,6 +1031,14 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_interleaved_dma( return chan->device->device_prep_interleaved_dma(chan, xt, flags); } +/** + * dmaengine_prep_dma_memset() - Prepare a DMA memset descriptor. + * @chan: The channel to be used for this descriptor + * @dest: Address of buffer to be set + * @value: Treated as a single byte value that fills the destination buffer + * @len: The total size of dest + * @flags: DMA engine flags + */ static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_memset( struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags)
Document this function to make clear the expected behavior of the 'value' parameter. It was intended to match the behavior of POSIX memset as laid out here: https://lore.kernel.org/dmaengine/YejrA5ZWZ3lTRO%2F1@matsya/ Signed-off-by: Ben Walker <benjamin.walker@intel.com> --- include/linux/dmaengine.h | 8 ++++++++ 1 file changed, 8 insertions(+)