| Message ID | caa86759ff67df73c10fc3738eac5de58d582cc1.1457606136.git.moinejf@free.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Mar 10, 2016 at 10:27:37AM +0100, Jean-Francois Moine wrote: > In the commit 1f9cd915b64bb95f "dmaengine: sun6i: Fix memcpy operation", > the signed values returned by convert_burst() and convert_buswidth() > were stored in an unsigned value. > Then, these values were considered as errors when non null. > As a result, setting burst or buswidth to values different from 1 was > making the DMA transfers to be rejected. A value of 0 for burst does not make sense. Frr buswidth this in undefined. So what are we gaining from 0 value and how is it fixing something which is passed as wrong argument? > > Signed-off-by: Jean-Francois Moine <moinejf@free.fr> > --- > drivers/dma/sun6i-dma.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c > index 2ec320d..3579ee7 100644 > --- a/drivers/dma/sun6i-dma.c > +++ b/drivers/dma/sun6i-dma.c > @@ -281,25 +281,25 @@ static inline int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, > dma_addr_t dst, u32 len, > struct dma_slave_config *config) > { > - u8 src_width, dst_width, src_burst, dst_burst; > + s8 src_width, dst_width, src_burst, dst_burst; > > if (!config) > return -EINVAL; > > src_burst = convert_burst(config->src_maxburst); > - if (src_burst) > + if (src_burst < 0) > return src_burst; > > dst_burst = convert_burst(config->dst_maxburst); > - if (dst_burst) > + if (dst_burst < 0) > return dst_burst; > > src_width = convert_buswidth(config->src_addr_width); > - if (src_width) > + if (src_width < 0) > return src_width; > > dst_width = convert_buswidth(config->dst_addr_width); > - if (dst_width) > + if (dst_width < 0) > return dst_width; > > lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) | > -- > 2.7.2 >
On Fri, 11 Mar 2016 12:12:27 +0530 Vinod Koul <vinod.koul@intel.com> wrote: > On Thu, Mar 10, 2016 at 10:27:37AM +0100, Jean-Francois Moine wrote: > > In the commit 1f9cd915b64bb95f "dmaengine: sun6i: Fix memcpy operation", > > the signed values returned by convert_burst() and convert_buswidth() > > were stored in an unsigned value. > > Then, these values were considered as errors when non null. > > As a result, setting burst or buswidth to values different from 1 was > > making the DMA transfers to be rejected. > > A value of 0 for burst does not make sense. Frr buswidth this in undefined. > So what are we gaining from 0 value and how is it fixing something which is > passed as wrong argument? The problem is not the null value, but a value different from 1: 8 as the burst or 4 as the bus width were rejected.
On Thu, Mar 10, 2016 at 10:27:37AM +0100, Jean-Francois Moine wrote: > In the commit 1f9cd915b64bb95f "dmaengine: sun6i: Fix memcpy operation", The commit title should be enclosed in parenthesis. > the signed values returned by convert_burst() and convert_buswidth() > were stored in an unsigned value. > Then, these values were considered as errors when non null. > As a result, setting burst or buswidth to values different from 1 was > making the DMA transfers to be rejected. > > Signed-off-by: Jean-Francois Moine <moinejf@free.fr> Otherwise, Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Thanks!
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c index 2ec320d..3579ee7 100644 --- a/drivers/dma/sun6i-dma.c +++ b/drivers/dma/sun6i-dma.c @@ -281,25 +281,25 @@ static inline int sun6i_dma_cfg_lli(struct sun6i_dma_lli *lli, dma_addr_t dst, u32 len, struct dma_slave_config *config) { - u8 src_width, dst_width, src_burst, dst_burst; + s8 src_width, dst_width, src_burst, dst_burst; if (!config) return -EINVAL; src_burst = convert_burst(config->src_maxburst); - if (src_burst) + if (src_burst < 0) return src_burst; dst_burst = convert_burst(config->dst_maxburst); - if (dst_burst) + if (dst_burst < 0) return dst_burst; src_width = convert_buswidth(config->src_addr_width); - if (src_width) + if (src_width < 0) return src_width; dst_width = convert_buswidth(config->dst_addr_width); - if (dst_width) + if (dst_width < 0) return dst_width; lli->cfg = DMA_CHAN_CFG_SRC_BURST(src_burst) |
In the commit 1f9cd915b64bb95f "dmaengine: sun6i: Fix memcpy operation", the signed values returned by convert_burst() and convert_buswidth() were stored in an unsigned value. Then, these values were considered as errors when non null. As a result, setting burst or buswidth to values different from 1 was making the DMA transfers to be rejected. Signed-off-by: Jean-Francois Moine <moinejf@free.fr> --- drivers/dma/sun6i-dma.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)