lkml.org 
[lkml]   [2013]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] dw_dmac: don't exceed AHB master number in dwc_get_data_width
Date
The driver's default assumes that hardware has two AHB masters which might be
not true. In such rare cases we have not to exceed a number of the AHB masters
present in the hardware. Thus, the AHB master with highest possible number will
be used to retrieve the data witdh value.

The patch also changes the logic a bit when the master parameter of the
dwc_get_data_width() is out of range. Now the function will return a value
related to the first AHB master.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/dma/dw_dmac.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index 30ff2a4..b2d564a 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -80,13 +80,14 @@ static inline unsigned int dwc_get_data_width(struct dma_chan *chan, int master)
{
struct dw_dma *dw = to_dw_dma(chan->device);
struct dw_dma_slave *dws = chan->private;
+ unsigned int m = 0;

if (master == SRC_MASTER)
- return dw->data_width[dwc_get_sms(dws)];
+ m = dwc_get_sms(dws);
else if (master == DST_MASTER)
- return dw->data_width[dwc_get_dms(dws)];
+ m = dwc_get_dms(dws);

- return 0;
+ return dw->data_width[min_t(unsigned int, dw->nr_masters - 1, m)];
}

/*----------------------------------------------------------------------*/
--
1.7.10.4


\
 
 \ /
  Last update: 2013-01-14 16:01    [W:0.057 / U:0.252 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site